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Sample records for citrus rootstock development

  1. In Vitro Propagation of Citrus Rootstocks

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    Suneel SHARMA

    2009-06-01

    Full Text Available Present investigation was conducted to standardize a protocol for in-vitro propagation of citrus rootstocks viz. Rough lemon, Cleopatra mandarin Pectinifera and Troyer citrange. The shoot tip explant was found better for callus induction of these rootstocks than the nodal segment. Maximum callus formation (40.0% and 23.3% of shoot tip explants was obtained in Cleopatra mandarin, Pectinifera, and Rough lemon and Troyer citrange, respectively in treatment MS basal media + 0.5mg/l Kin, 2.0mg/l NAA, and 2.0mg/l 2, 4-D. Furthermore, the maximum number of shoots per explant was obtained through the callus in Pectinifera, Rough lemon and Cleopatra mandarin in MS basal media + BAP 1mg/l. Maximum rooting of shoots (1.11% was noted in rootstock Rough lemon followed by Cleopatra mandarin for the � MS media supplemented with 10mg/l IBA. Although the callus development and bud proliferation was recorded in rootstock Troyer citrange however, shoot and root formation did not occur. The potting media consisting of soil, sand and FYM in the ratio of 1:1:1 by volume was better with maximum survival rate of hardened plants six weeks after transferring to the pots under greenhouse for Rough lemon followed by Pectinifera and Cleopatra mandarin rootstock.

  2. Bacteria as growth-promoting agents for citrus rootstocks.

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    Giassi, Valdionei; Kiritani, Camila; Kupper, Katia Cristina

    2016-09-01

    The microbial community plays an essential role in maintaining the ecological balance of soils. Interactions between microorganisms and plants have a major influence on the nutrition and health of the latter, and growth-promoting rhizobacteria can be used to improve plant development through a wide range of mechanisms. Therefore, the objective of the present study was to evaluate bacteria as growth-promoting agents for citrus rootstocks. A total of 30 bacterial isolates (11 of Bacillus spp., 11 actinobacteria, and 8 lactic acid bacteria) were evaluated in vitro for indoleacetic acid production, phosphate solubilization, and nitrogen (N) fixation. In vivo testing consisted of growth promotion trials of the bacterial isolates that yielded the best results on in vitro tests with three rootstocks: Swingle citrumelo [Citrus×paradisi Macfad cv. Duncan×Poncirus trifoliata (L.) Raf.], Sunki mandarin (Citrus sunki Hort. ex Tan), and rangpur (Citrus×limonia Osbeck). The parameters of interest were height, number of leaves, stem diameter, shoot and root dry mass, and total dry mass at 150days after germination. The results showed that most bacterial isolates were capable of IAA production. Only one lactic acid bacterium isolate (BL06) solubilized phosphate, with a high solubilization index (PSI>3). In the actinobacteria group, isolates ACT01 (PSI=2.09) and ACT07 (PSI=2.01) exhibited moderate phosphate-solubilizing properties. Of the Bacillus spp. isolates, only CPMO6 and BM17 solubilized phosphate. The bacterial isolates that most fixated nitrogen were BM17, ACT11, and BL24. In the present study, some bacteria were able to promote growth of citrus rootstocks; however, this response was dependent on plant genotype and isolate. Bacillus spp. BM16 and CPMO4 were able to promote growth of Swingle citrumelo. In Sunki mandarin plants, the best treatment results were obtained with BM17 (Bacillus sp.) and ACT11 (actinobacteria). For Rangpur lime rootstock, only BM05 (Bacillus sp

  3. Citrus rootstocks influence the population densities of pest mites

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    Rafael Rocha da Silva

    2016-01-01

    Full Text Available Citrus are attacked by pest mites such as the citrus rust mite Phyllocoptruta oleivora (Ashmead (Acari: Eriophyidae and the spider mite Tetranychus mexicanus (McGregor (Acari: Tetranychidae. However, little is known on citrus rootstocks influencing pest mites. We aimed to evaluate the influence of rootstocks on population densities of pest mites on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' throughout time. Adults of both mite species were monthly counted during 19 months from June 2011 to February 2013. Rootstocks influenced the populations of pest mites, since lower densities of P. oleivora were found on 'Pera CNPMF D-6' sweet orange grafted on the hybrid TSKC × CTTR - 002 and on 'Swingle' citrumelo in comparison with the hybrid LVK × LCR - 010, 'Red' rough lime and 'Santa Cruz' rangpur lime as rootstocks. Similarly, lower densities of T. mexicanus were found on 'Valencia Tuxpan' sweet orange grafted on the hybrid HTR-051 in comparison to 'Indio' citrandarin, 'Sunki Tropical' mandarin and LVK × LCR - 010 as rootstocks. We concluded that densities of the mites P. oleivora and T. mexicanus on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' were affected in some periods of the year by some rootstocks, suggesting influence of some genotypes on these pests.

  4. Desenvolvimento vegetativo e custo de produção de porta-enxertos de citros em recipientes para fins de subenxertia Vegetative development and production cost of citrus rootstocks in containers for inarching

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    Eduardo Augusto Girardi

    2007-05-01

    Full Text Available O objetivo deste trabalho foi avaliar o desenvolvimento vegetativo e estimar o custo de produção de 11 porta-enxertos de citros para fins de subenxertia, em diferentes recipientes. Avaliaram-se limão 'Cravo' clone Limeira (Citrus limonia Osbeck; citrumelo 'Swingle' (Poncirus trifoliata (L. Raf. x Citrus paradisi Macf.; tangerina 'Cleópatra' (Citrus reshni Hort. ex Tanaka; tangerina 'Sunki' (Citrus sunki Hort. ex Tanaka; limão 'Volkameriano' clone Catânia 2 (Citrus volkameriana Pasquale; laranja 'Caipira' clone DAC (Citrus sinensis L. Osbeck; limão 'Rugoso da África' clone Mazoe (Citrus jambhiri Lush.; Poncirus trifoliata 'Davis A'; tangerina 'Sun Shu Sha Kat' (Citrus sunki Hort. ex Tanaka; tangerina 'Sunki' clone 2506 ou Fruto Grande (Citrus sunki Hort. ex Tanaka e Poncirus trifoliata 'Barnes'. Foram utilizados tubetes de 290 mL, sacolas de 1,7 L, e porta-enxertos transplantados de tubetes de 75 mL para sacolas de polietileno de 1,7 e 4,5 L. Porta-enxertos produzidos diretamente em sacolas de 1,7 L atingem ponto ideal de subenxertia em menor tempo, de 100 a 150 dias após a semeadura, e permitem a obtenção de plantas maiores e com sistema radicular adequado, porém com custo de produção superior ao sistema de produção em tubetes de 290 mL.The vegetative development and the estimation of the production cost of eleven citrus rootstocks for inarching were evaluated in different containers. 'Rangpur' lime cultivar Limeira (Citrus limonia Osbeck; 'Swingle' citrumelo (Poncirus trifoliata (L. Raf. x Citrus paradisi Macf.; 'Cleópatra' mandarin (Citrus reshni Hort. ex Tanaka; 'Sunki' mandarin (Citrus sunki Hort. ex Tanaka; 'Volkamer' lemon cultivar Catânia 2 (Citrus volkameriana Pasquale; 'Caipira' sweet orange cultivar DAC (Citrus sinensis L. Osbeck; 'Rugoso da África' rough lemon cultivar Mazoe (Citrus jambhiri Lush.; Poncirus trifoliata cultivar Davis A; 'Sun Shu Sha Kat' mandarin (Citrus sunki Hort. ex Tanaka; 'Sunki' mandarin

  5. Influence of different levels of aluminum on the development of citrus rootstock swingle citrumelo (Citrus paradisi mcf. x Poncirus trifoliata raf. in nutrient solution

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    Carlos Henrique dos Santos

    2000-01-01

    Full Text Available This work aimed at evaluating the influence of different levels of aluminum on the physiological parameters of the citrus rootstock Swingle Citrumelo in hydroponic solution. The experiment was carried out with a completely randomized design with three replications, subdivided in several lots. The levels of aluminum used were: 0, 7.5, 15, 22.5 and 30 mg L-1 in form of AlCl3.6H2O in nutrient solution. Following physiological parameters were evaluated: specific and relative foliar area, relative foliar mass, and the ratio of aerial part dry matter/root system dry matter. The results showed that aluminum did not influence the parameters evaluated except the specific foliar area, which decreased starting at the 7.5 mg L-1 level.O presente trabalho teve como objetivo avaliar a influência de diferentes níveis de alumínio nos parâmetros fisiológicos do porta-enxerto cítrico citrumeleiro Swingle em cultivo hidropônico. O experimento foi conduzido seguindo o delineamento estatístico inteiramente casualizado, com 3 repetições, em parcelas subdivididas. Os níveis de alumínio utilizados foram: 0, 7,5, 15, 22,5 e 30 mg L-1, na forma de AlCl3 6.H2O em solução nutritiva. Foram avaliados os parâmetros fisiológicos área foliar específica, razão de área foliar e massa foliar, relação matéria seca da parte aérea/matéria seca do sistema radicular. De acordo com os resultados obtidos nestas condições, conclui-se que os níveis de alumínio não influenciaram nos valores dos parâmetros acima discutidos, excetuando-se a AFE, havendo decréscimos destes valores a partir de 7,5 mg L-1 de alumínio.

  6. The genetics of tolerance to tristeza disease in citrus rootstocks

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    Rita Bordignon

    2004-01-01

    Full Text Available Controlled pollinations between four elite citrus rootstocks, Citrus limonia - 'Limeira' rangpur lime (Cravo, C. sunki - 'Sunki' mandarin (Sunki, C. aurantium - 'São Paulo' sour orange (Azeda and Poncirus trifoliata - 'Davis A' trifoliate orange (Trifoliata, resulted in 1614 nucelar and 1938 hybrid plants identified by the isozyme loci Pgi-1, Pgm-1, Got-1, Got-2, Aps-1, Me-1, Prxa-1 and or by the morphological markers broadness of leaf petiole wing or trifoliolate leaves. Tolerance to the citrus tristeza virus (CTV was evaluated under nursery and field conditions for several years by the reaction of Valencia orange infected with a severe strain of CTV and grafted onto the hybrids and nucellar clones. Genetic analyses indicated that tolerance was controlled by at least two loci designated here as Az and t interacting in dominant-recessive epistasis. Genotypes Az__ __ __ and __ __ tt were tolerant while azaz T__ was intolerant. The intolerant Azeda was azaz TT, the tolerant rootstocks Sunki and Cravo were Azaz tt and the Trifoliata was Azaz TT. The different degrees of intolerance seen in some hybrids may reflect the inability of segregating modifiers from parental clones to overcome the epistatic interaction that controls the major tolerance reaction.

  7. Monitoring the viability of citrus rootstocks seeds stored under refrigeration

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    Sérgio Alves de Carvalho

    2013-03-01

    Full Text Available The citrus nursery tree is produced through the bud grafting process, in which rootstock is usually grown from seed germination. The objective of this research was to evaluate, in two dissimilar environmental conditions, the viability and polyembryony expression of five citrus rootstocks seeds stored in different periods under refrigeration. The rootstock varieties evaluated were: Rangpur lime (Citrus limonia Osb. cv. Limeira, Trifoliate orange (Poncirus trifoliata Raf. cv. Limeira, Citrumelo (P. trifoliata x C. paradisi Macf. cv. Swingle, Sunki mandarin (C. sunki Hort. ex Tanaka and Volkamer lemon (C. volkameriana Ten. & Pasq. cv. Catania 2. The experimental design was the randomized blocks in a 11 x 5 x 2 factorial scheme, evaluating from time zero to the tenth month of storage, the five varieties of rootstock in two environments: germination and growth B.O.D type chamber (Biological Oxygen Demand - Eletrolab Brand Model FC 122 at 25 °C; and greenhouse seedbed with partial temperature control (22 °C to 36 °C and humidity control (75-85%. The plot had 24 seeds in four replicates, using trays with substrate in greenhouse and Petri dishes with filter paper in B.O.D. chamber. The seed germination rate and polyembryony expression were evaluated monthly. It was concluded that Trifoliate and Citrumelo Swingle seeds can be stored for up to seven months, while Volkamer lemon, Rangpur lime and Sunki seeds can be stored for up to ten months. The polyembryony expression rate was slightly higher when measured in greenhouse than in B.O.D. chamber and remained stable in both environments until the seventh month, from which dropped sharply. Citrumelo Swingle seeds expressed the highest polyembryony rate (18.8%, followed by Rangpur lime and Volkamer lemon (average value of 13.7%, Sunki (9.4% and Trifoliate (3.2%. Despite some differences among varieties, the viability of rootstock stored seeds can be monitored either in the greenhouse or in B

  8. 柑桔砧木育种研究进展%Advances in Citrus Rootstock Breeding

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    朱世平; 江东; 洪棋斌; 龚桂芝; 刘小丰; 赵晓春

    2013-01-01

    柑桔主要通过嫁接进行繁殖.柑桔砧木对接穗生长势、产量、果实大小、品质和抗性等都有直接的影响.砧木遗传改良是保持柑桔产业具有较强竞争力和较高生产力的重要步骤,世界各国都在致力于柑桔优良砧木的培育.本文就近几十年来柑桔砧木育种进展进行简要综述.%Citrus is mainly propagated by grafting. The rootstock directly affects the growth vigor, production, fruit size and quality, and stress-responsiveness of the scion. The health and productivity of citrus industry is greatly dependent on the performance of the rootstocks. The genetic improvement of citrus rootstocks has become a vital step towards the industry being more productive and competitive. In most of citrus growing countries, selecting and creating superior rootstock is one of the most important practices in citrus breeding. In this paper, the progresses in citrus root-stock breeding in the past decades will be briefly reviewed.

  9. Tetraploid citrus rootstocks are more tolerant to salt stress than diploid.

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    Saleh, Basel; Allario, Thierry; Dambier, Dominique; Ollitrault, Patrick; Morillon, Raphaël

    2008-09-01

    Citrus trees are subject to several abiotic constraints such as salinity. Providing new rootstocks more tolerant is thus a requirement. In this article, we investigated salt stress tolerance of three tetraploid rootstock genotypes when compared to their respective diploid rootstocks (Poncirus trifoliata, Carrizo citrange, Cleopatra mandarin). Plant growth, leaf fall and ion contents were investigated. At the end of the experiment, leaf fall was observed only for diploid Poncirus trifoliata plants as well as chlorosis symptoms for Poncirus trifoliata and Carrizo citrange diploid plants. The diploid Cleopatra mandarin plants growth rate was not affected by salt stress and has even been increased for tetraploid Cleopatra mandarin. Ion contents investigation has shown lower accumulations of chloride ions in leaves of the tetraploid plants when compared to diploid plants. Our results suggest that citrus tetraploid rootstocks are more tolerant to salt stress than their corresponding diploid.

  10. Transcriptome Profiling to Understand the Effect of Citrus Rootstocks on the Growth of 'Shatangju' Mandarin.

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    Liu, Xiang-Yu; Li, Juan; Liu, Meng-Meng; Yao, Qing; Chen, Jie-Zhong

    2017-01-01

    To obtain insight into potential mechanisms underlying the influence of rootstock on scion growth, we performed a comparative analysis of 'Shatangju' mandarin grafted onto 5 rootstocks: Fragrant orange (Citrus junons Sieb. ex. Tanaka), Red tangerine (Citrus reticulata Blanco), 'Shatangju' mandarin (Citrus reticulata Blanco), Rough lemon (Citrus jambhiri Lush) and Canton lemon (Citrus limonia Osbeck). The tree size of 'Shatangju' mandarin grafted onto Canton lemon and Rough lemon were the largest, followed by self-rooted rootstock trees, and the lowest tree sizes correspond to ones grafted on Red tangerine and Fragrant orange rootstocks. The levels of indoleacetic acid (IAA) and gibberellin (GA) were significantly and positively related to growth vigor. The differences of gene expression in leaves of trees grafted onto Red tangerine, Canton lemon and 'Shatangju' mandarin were analyzed by RNA-Seq. Results showed that more differentially expressed genes involved in oxidoreductase function, hormonal signal transduction and the glycolytic pathway were enriched in 'Red tangerine vs Canton lemon'. qRT-PCR analysis showed that expression levels of ARF1, ARF8, GH3 and IAA4 were negatively correlated with the growth vigor and IAA content. The metabolism of GA was influenced by the differential expression of KO1 and GA2OX1 in grafted trees. In addition, most of antioxidant enzyme genes were up-regulated in leaves of trees grafted onto Red tangerine, resulting in a higher peroxidase activity. We concluded that different rootstocks significantly affected the expression of genes involved in auxin signal transduction pathway and GA biosynthesis pathway in the grafted plants, and then regulated the hormone levels and their signal pathways.

  11. Regulation of nitrate transport in citrus rootstocks depending on nitrogen availability.

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    Cerezo, Miguel; Camañes, Gemma; Flors, Víctor; Primo-Millo, Eduardo; García-Agustín, Pilar

    2007-09-01

    Previously, we reported that in Citrus plants, nitrate influx through the plasmalemma of roots cells follows a biphasic pattern, suggesting the existence of at least two different uptake systems, a high and low affinity transport system (HATS and LATS, respectively). Here, we describe a novel inducible high affinity transport system (iHATS). This new nitrate transport system has a high capacity to uptake nitrate in two different Citrus rootstocks (Cleopatra mandarin and Troyer citrange). The iHATS was saturable, showing higher affinity than constitutive high affinity transport system (cHATS) to the substrate NO(3) (-). The V(max) for this saturable component iHATS was higher than cHATS, reaching similar values in both rootstocks.Additionally, we studied the regulation of root NO(3) (-) uptake mediated by both HATS (iHATS and cHATS) and LATS. In both rootstocks, cHATS is constitutive and independent of N-status. Concerning the regulation of iHATS, this system is upregulated by NO(3) (-) and down-regulated by the N status and by NO(3) (-) itself when plants are exposed to it for a longer period of time. LATS in Cleopatra mandarin and Troyer citrange rootstocks is repressed by the N-status.The use of various metabolic uncouplers or inhibitors indicated that NO(3) (-) net uptake mediated by iHATS and LATS was an active transport system in both rootstocks.

  12. Assessment of the genetic diversity of the Tunisian citrus rootstock germplasm

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    Snoussi Hager

    2012-03-01

    Full Text Available Abstract Background Citrus represents a substantial income for farmers in the Mediterranean Basin. However, the Mediterranean citrus industry faces increasing biotic and abiotic constraints. Therefore the breeding and selection of new rootstocks are now of the utmost importance. In Tunisia, in addition to sour orange, the most widespread traditional rootstock of the Mediterranean area, other citrus rootstocks and well adapted to local environmental conditions, are traditionally used and should be important genetic resources for breeding. To characterize the diversity of Tunisian citrus rootstocks, two hundred and one local accessions belonging to four facultative apomictic species (C. aurantium, sour orange; C. sinensis, orange; C. limon, lemon; and C. aurantifolia, lime were collected and genotyped using 20 nuclear SSR markers and four indel mitochondrial markers. Multi-locus genotypes (MLGs were compared to references from French and Spanish collections. Results The differentiation of the four varietal groups was well-marked. The groups displayed a relatively high allelic diversity, primarily due to very high heterozygosity. Sixteen distinct MLGs were identified. Ten of these were noted in sour oranges. However, the majority of the analysed sour orange accessions corresponded with only two MLGs, differentiated by a single allele, likely due to a mutation. The most frequent MLG is shared with the reference sour oranges. No polymorphism was found within the sweet orange group. Two MLGs, differentiated by a single locus, were noted in lemon. The predominant MLG was shared with the reference lemons. Limes were represented by three genotypes. Two corresponded to the 'Mexican lime' and 'limonette de Marrakech' references. The MLG of 'Chiiri' lime was unique. Conclusions The Tunisian citrus rootstock genetic diversity is predominantly due to high heterozygosity and differentiation between the four varietal groups. The phenotypic diversity within the

  13. Rootstocks for 'Tahiti' lime

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    Stenzel Neusa Maria Colauto

    2004-01-01

    Full Text Available The 'Tahiti' lime (Citrus latifolia Tanaka is an important commercial citrus cultivar in Brazil. 'Rangpur' lime has being used as its main rootstock, but it is susceptible to root rot caused by Phytophthora, reducing tree longevity. An experiment was set up in a randomized block design, with three trees per plot of each rootstock and four replicates, and run for 12 years, aiming to compare the performance of 'IAC-5 Tahiti' lime, budded on 'Rangpur' lime (Citrus limonia Osb.; 'C-13' citrange (Citrus sinensis (L. Osb. × Poncirus trifoliata (L. Raf.; 'African' rough lemon (Citrus jambhiri Lush.; 'Volkamer' lemon (Citrus volkameriana Ten. & Pasq.; trifoliate orange (Poncirus trifoliata (L. Raf.; 'Sunki' mandarin (Citrus sunki Hort. ex Tan. and 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan.. Eleven years after the establishment of the orchard, trees with the greatest canopy development were budded on 'C-13' citrange and 'African' rough lemon, and both differed significantly from trees budded on trifoliate orange, 'Sunki' and 'Cleopatra' mandarins, which presented the smallest canopy development. Trees budded on 'Rangpur' lime and 'C-13' citrange had the highest cumulative yields, and were different from trees budded on trifoliate orange, 'Cleopatra' and 'Sunki' mandarins. There was no rootstock effect on mean fruit weight and on the total soluble solid/acid ratio in the juice. The 'Rangpur' lime and the 'Cleopatra' mandarin rootstocks reduced longevity of plants.

  14. Anatomical and Physiological Responses of Citrus Trees to Varying Boron Availability Is Dependent on Rootstock

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    Geisa Lima Mesquita

    2016-03-01

    Full Text Available In Citrus, water, nutrient transport and thereby fruit production, are influenced among other factors, by the interaction between rootstock and boron (B nutrition. This study aimed to investigate how B affects the anatomical structure of roots and leaves as well as leaf gas exchange in sweet orange trees grafted on two contrasting rootstocks in response to B supply. Plants grafted on Swingle citrumelo or Sunki mandarin were grown in a nutrient solution of varying B concentration (deficient, adequate, and excessive. Those grafted on Swingle were more tolerant to both B deficiency and toxicity than those on Sunki, as revealed by higher shoot and root growth. In addition, plants grafted on Sunki exhibited more severe anatomical and physiological damages under B deficiency, showing thickening of xylem cell walls and impairments in whole-plant, leaf-specific hydraulic conductance and leaf CO2 assimilation. Our data revealed that trees grafted on Swingle sustain better growth under low B availablitlity in the root medium and still respond positively to increased B levels by combining higher B absorption and root growth as well as better organization of xylem vessels. Taken together, those traits improved water and B transport to the plant canopy. Under B toxicity, Swingle rootstock would also favor plant growth by reducing anatomical and ultrastructural damage to leaf tissue and improving water transport compared with plants grafted on Sunki. From a practical point of view, our results highlight that B management in citrus orchards shall take into account rootstock varieties, of which the Swingle rootstock was characterized by its performance on regulating anatomical and ultrastructural damages, improving water transport and limiting negative impacts of B stress conditions on plant growth.

  15. Anatomical and Physiological Responses of Citrus Trees to Varying Boron Availability Are Dependent on Rootstock.

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    Mesquita, Geisa L; Zambrosi, Fernando C B; Tanaka, Francisco A O; Boaretto, Rodrigo M; Quaggio, José A; Ribeiro, Rafael V; Mattos, Dirceu

    2016-01-01

    In Citrus, water, nutrient transport and thereby fruit production, are influenced among other factors, by the interaction between rootstock and boron (B) nutrition. This study aimed to investigate how B affects the anatomical structure of roots and leaves as well as leaf gas exchange in sweet orange trees grafted on two contrasting rootstocks in response to B supply. Plants grafted on Swingle citrumelo or Sunki mandarin were grown in a nutrient solution of varying B concentration (deficient, adequate, and excessive). Those grafted on Swingle were more tolerant to both B deficiency and toxicity than those on Sunki, as revealed by higher shoot and root growth. In addition, plants grafted on Sunki exhibited more severe anatomical and physiological damages under B deficiency, showing thickening of xylem cell walls and impairments in whole-plant leaf-specific hydraulic conductance and leaf CO2 assimilation. Our data revealed that trees grafted on Swingle sustain better growth under low B availablitlity in the root medium and still respond positively to increased B levels by combining higher B absorption and root growth as well as better organization of xylem vessels. Taken together, those traits improved water and B transport to the plant canopy. Under B toxicity, Swingle rootstock would also favor plant growth by reducing anatomical and ultrastructural damage to leaf tissue and improving water transport compared with plants grafted on Sunki. From a practical point of view, our results highlight that B management in citrus orchards shall take into account rootstock varieties, of which the Swingle rootstock was characterized by its performance on regulating anatomical and ultrastructural damages, improving water transport and limiting negative impacts of B stress conditions on plant growth.

  16. Different Citrus rootstocks present high dissimilarities in their antioxidant activity and vitamins content according to the ripening stage.

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    Cardeñosa, Vanessa; Barros, Lillian; Barreira, João C M; Arenas, Francisco; Moreno-Rojas, José M; Ferreira, Isabel C F R

    2015-02-01

    "Lane Late" sweet orange grafted on six different citrus rootstocks and grown in the Guadalquivir valley (Seville, Spain) were picked at different ripening stages in two consecutive seasons to characterize their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and quantify their main antioxidant compounds (vitamin E and vitamin C). Linear discriminant analysis and 2-way ANOVA were applied to compare the effects induced by citrus rootstock and ripening stage. The results showed that differences in antioxidant activity and related compounds are mainly dependent on the citrus rootstock, despite ripening stage had also some particular effects. Changes observed in 2012 showed less marked differences among the citrus rootstock. Nevertheless, Cleopatra rootstock showed the highest antioxidant activity in both years, indicating that an increase in its cultivation might be a good solution to sweet orange farmers. Concerning the ripening stage, samples collected in January presented higher vitamin contents, while those collected in April showed higher antioxidant activity. This result allows deciding the harvesting period according to the desired effect.

  17. Comparison between diploid and tetraploid citrus rootstocks: morphological characterization and growth evaluation

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    Divanilde Guerra

    2014-03-01

    Full Text Available Tetraploid citrus rootstocks may present different morphological characteristics and growth when compared to diploid ones. This worked aimed at comparing morphological characteristics and height growth of diploid and tetraploid plants from the rootstocks 'Swingle' citrumelo [C. paradise Macf. x Poncirus trifoliate (L. Raf], citrange 'Troyer' (C. sinensis (L. Osb. x P. trifoliata and citranges 'Fepagro C 13' and 'Fepagro C 37' [C. sinensis cv. Pêra x P. trifoliata] during twelve months. Diploid (2n=18 and tetraploid (2n=36 plants originated from the same seed were identified, cultivated and evaluated every 45 days regarding color, height, petiole length, leaf length and central leaflet width. Significant differences were observed for the evaluated characteristics: the average of petiole length was 1.78 cm in the diploid and 0.99 cm in the tetraploid plants; the average of leaf length was 2.32 cm in the diploid and 2.95 cm in the tetraploid plants; the average of central leaflet width was 1.33 cm in the diploid and 1.69 cm in the tetraploid plants. Moreover, tetraploid plants had darker and thicker leaves than the diploid ones. Variation regarding height was observed and the diploid plants presented higher growth than the tetraploid ones. As tetraploid plants are smaller, have a slow height growth and wider and longer leaves.

  18. Host Range of a Population of Pratylenchus vulnus in Commercial Fruit, Nut, Citrus, and Grape Rootstocks in Spain.

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    Pinochet, J; Verdejo, S; Soler, A; Canals, J

    1992-12-01

    In a host-range study carried out under greenhouse conditions, a total of 37 commercial fruit tree, grape, and citrus rootstocks were tested for their reaction to a population of the lesion nematode, Pratylenchus vulnus, in Spain. Twenty-five rootstocks had a Pf/Pi > 1.5. These included almond (Desmayo Rojo, 1143), apple (EM-9, EM-106), avocado (Hass), cherry (Santa Lucia 64, Camil, M x M 14, Masto de Montafiana), grape (41-B, Fercal, Ritcher 110), hazelnut (Pauetet), loquat (Nadal), peach (Montclar, GF-305), pear (OHF-333), pistachio (P. atlantica, P. vera, P. terebinthus), plum (San Julian 655-2, Montizo, Pixy, Myrobalan 605), and walnut (Serf). The peach rootstock Nemaguard and the grape 161-49 had Pf/Pi between 1.0 and 1.5 (slightly higher than inoculation level). All the tested citrus (Alemow, rough lemon, Carrizo citrange, sour orange, Troyer citrange, Citrumelo), plus three grape (SO4, Vitis rupestris, 1103-P), and the olive rootstock Arbequina had a Pf/Pi < 1.0.

  19. Metabolic variations in different citrus rootstock cultivars associated with different responses to Huanglongbing.

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    Albrecht, Ute; Fiehn, Oliver; Bowman, Kim D

    2016-10-01

    Huanglongbing (HLB) is one of the most destructive bacterial diseases of citrus. No resistant cultivars have been identified, although tolerance has been observed in the genus Poncirus and some of its hybrids with Citrus that are commonly used as rootstocks. In this study we exploited this tolerance by comparing five different tolerant hybrids with a cultivar that shows pronounced HLB sensitivity to discern potential contributing metabolic factors. Whole leaves of infected and non-infected greenhouse-grown seedlings were extracted and subjected to untargeted GC-TOF MS based metabolomics. After BinBase data filtering, 342 (experiment 1) and 650 (experiment 2) unique metabolites were quantified, of which 122 and 195, respectively, were assigned by chemical structures. The number of metabolites found to be differently regulated in the infected state compared with the non-infected state varied between the cultivars and was largest (166) in the susceptible cultivar Cleopatra mandarin (Citrus reticulata) and lowest (3) in the tolerant cultivars US-897 (C. reticulata 'Cleopatra' × Poncirus trifoliata) and US-942 (C. reticulata 'Sunki' × P. trifoliata) from experiment 2. Tolerance to HLB did not appear to be associated with accumulation of higher amounts of protective metabolites in response to infection. Many metabolites were found in higher concentrations in the tolerant cultivars compared with susceptible Cleopatra mandarin and may play important roles in conferring tolerance to HLB. Lower availability of specific sugars necessary for survival of the pathogen may also be a contributing factor in the decreased disease severity observed for these cultivars.

  20. Produção de mudas cítricas em diferentes porta-enxertos e substratos comerciais Citrus nursery production with different rootstocks and commercial substrates

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    Mário Luís Fochesato

    2006-10-01

    Full Text Available Analisou-se o desenvolvimento de duas variedades-copa enxertadas sobre diversos porta-enxertos e produzidas em substratos comerciais sob ambiente protegido. O experimento foi desenvolvido em casa de vegetação na Estação Experimental Agronômica da UFRGS, em Eldorado do Sul, RS, no período de fevereiro a novembro/2004. O delineamento experimental foi de blocos casualizados em esquema fatorial 2x3x3, sendo testados: 2 variedades-copa (laranjeira "Valência" - C. sinensis [L.] Osbeck e tangerineira "Montenegrina" - C. sinensis Tenore, 3 porta-enxertos (Trifoliata - C. sinensis [L.] Raf.; citrangeiro "C13" - Citrus sinensis [L.] Osbeck x P. trifoliata [L.] Raf.; e limoeiro "Cravo" - C. limonia Osbeck e 3 substratos comerciais (Comercial 1, 2 e 3, e As mudas foram produzidas em citropotes de quatro litros, com sistema de irrigação por gotejamento. A análise revelou que o substrato Comercial 2 possibilitou maior desenvolvimento vegetativo às variedades-copa. O porta-enxerto citrangeiro "C13" pode ser uma alternativa aos porta-enxertos tradicionais usados no Brasil.The vegetative development of citrus nursery varieties grafted on three rootstocks at greenhouse conditions under different commercial substrates was evaluated. The experiment, randomized blocks, in a 2x3x3 factorial, was conducted at the research station of the Uiversidade Federal do Rio Grande do Sul, Eldorado do Sul, RS, Brazil, from February to November 2004. The treatments were two citrus varieties ('Valencia' Orange - Citrus sinensis [L.] Osb. and 'Montenegrina' mandarin - Citrus deliciosa Ten., citrus rootstoocks (Trifoliate orange - C. sinensis (L. Raf., citrange 'C13' - P. trifoliata x Citrus sinensis (L. Osb. and 'Rangpur' lemon - C. limonia Osb. and substrates (Commercial 1, 2, and 3. Plants were grown in containers (4 L with drip irrigation system. The Commercial 2 substrate showed the best performance in inducing plant growth. The citrange 'C13' may be an alternative to

  1. Alleviation of salt stress in citrus seedlings inoculated with arbuscular mycorrhizal fungi depends on the rootstock salt tolerance.

    Science.gov (United States)

    Navarro, Josefa M; Pérez-Tornero, Olaya; Morte, Asunción

    2014-01-01

    Seedlings of Cleopatra mandarin (Citrus reshni Hort. ex Tan.) and Alemow (Citrus macrophylla Wester) were inoculated with a mixture of AM fungi (Rhizophagus irregularis and Funneliformis mosseae) (+AM), or left non-inoculated (-AM). From forty-five days after fungal inoculation onwards, half of +AM or -AM plants were irrigated with nutrient solution containing 50 mM NaCl. Three months later, AM significantly increased plant growth in both Cleopatra mandarin and Alemow rootstocks. Plant growth was higher in salinized +AM plants than in non-salinized -AM plants, demonstrating that AM compensates the growth limitations imposed by salinity. Whereas AM-inoculated Cleopatra mandarin seedlings had a very good response under saline treatment, inoculation in Alemow did not alleviate the negative effect of salinity. The beneficial effect of mycorrhization is unrelated with protection against the uptake of Na or Cl and the effect of AM on these ions did not explain the different response of rootstocks. This response was related with the nutritional status since our findings confirm that AM fungi can alter host responses to salinity stress, improving more the P, K, Fe and Cu plant nutrition in Cleopatra mandarin than in Alemow plants. AM inoculation under saline treatments also increased root Mg concentration but it was higher in Cleopatra mandarin than in Alemow. This could explain why AM fungus did not completely recovered chlorophyll concentrations in Alemow and consequently it had lower photosynthesis rate than control plants. AM fungi play an essential role in citrus rootstock growth and biomass production although the intensity of this response depends on the rootstock salinity tolerance.

  2. Cadmium accumulation and strategies to avoid its toxicity in roots of the citrus rootstock Citrumelo

    Energy Technology Data Exchange (ETDEWEB)

    Podazza, Griselda [Instituto de Ecologia, Fundacion Miguel Lillo, Miguel Lillo 251, CP 4000, Tucuman (Argentina); Arias, Marta [Catedra de Anatomia Vegetal, Facultad de Ciencias Naturales e IML, Miguel Lillo 205, CP 4000, Tucuman (Argentina); Prado, Fernando E., E-mail: prad@arnet.com.ar [Catedra de Fisiologia Vegetal, Facultad de Ciencias Naturales e IML, Miguel Lillo 205, CP 4000, Tucuman (Argentina)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Cd induces oxidative stress, increasing the H{sub 2}O{sub 2} and O{sub 2}{center_dot}{sup -} generation. Black-Right-Pointing-Pointer SOD, G-POD, CAT activities are enhanced by Cd. Black-Right-Pointing-Pointer G-POD activity participates in Cd-induced lignin synthesis. Black-Right-Pointing-Pointer Cd mainly accumulates in exodermis and vascular cylinder. Black-Right-Pointing-Pointer Cd is mostly immobilized in roots, limiting its transport to aerial parts. - Abstract: In order to assess implications of Cd-induced oxidative stress in roots of the citrus rootstock Citrumelo, seedlings were hydroponically exposed to two relatively realistic Cd concentrations during 7 days. Our results showed that increasing Cd concentrations in external solution were associated with higher Cd accumulations in roots. At 5 {mu}M Cd the accumulation of Cd in roots was over 70-f higher than in aerial part (stem + leaves). Malondialdehyde (MDA), superoxide radical (O{sub 2}{center_dot}{sup -}), hydrogen peroxide (H{sub 2}O{sub 2}) and lipoxygenase activity (LOX) increased in Cd-exposed roots, suggesting a metal-induced oxidative stress. The Cd treatment enhanced the activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and guaiacol-type peroxidase (G-POD), as well as the content of secondary metabolites i.e. soluble phenolics (SPs) and lignin. Histochemical analyses of roots showed that Cd, H{sub 2}O{sub 2}, (O{sub 2}{center_dot}{sup -}), lignin and G-POD displayed a similar location pattern. Almost all analyzed parameters showed a similar dynamic tendency with increases under 5 {mu}M Cd followed by decreases under 10 {mu}M Cd, suggesting that a complex coordinated Cd-defensive mechanism is operating in Citrumelo roots exposed to environmental realistic Cd concentrations.

  3. Effects of rootstock on the composition of bergamot (Citrus bergamia Risso et Poiteau) essential oil.

    Science.gov (United States)

    Verzera, Antonella; Trozzi, Alessandra; Gazea, Florea; Cicciarello, Giuseppe; Cotroneo, Antonella

    2003-01-01

    This paper reports the composition of bergamot oils obtained from plants grafted on the following rootstocks: sour orange, Carrizo citrange, trifoliate orange, Alemow, Volkamerian lemon, and Troyer citrange. The aim of this study is to evaluate the possibility of using rootstocks other than sour orange, checking their effect on the composition of the essential oil. Results are reported for analysis of 203 bergamot oils during the years 1997-1998, 1998-1999, and 1999-2000. The oils were analyzed by HRGC and HRGC/MS; 78 components were identified, and the results were in agreement with those reported in the literature for the Calabrian bergamot oils obtained from industry. Because of the quality of their essential oils, Alemow and Volkamerian lemon can be considered as substitutes for sour orange rootstocks.

  4. Caipira sweet orange + Rangpur lime: a somatic hybrid with potential for use as rootstock in the Brazilian citrus industry

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    Fernanda Januzzi Mendes-da-Glória

    2000-09-01

    Full Text Available Protoplast culture following polyethylene glycol-induced fusion resulted in the regeneration of somatic hybrid plants between Caipira sweet orange (Citrus sinensis L. Osbeck and Rangpur lime (C. limonia L. Osbeck. The plants were confirmed as somatic hybrids by leaf morphology, chromosome number and RAPD profile. All regenerated plants were tetraploid (2n = 4x = 36, with intermediate leaf morphology and complementary RAPD banding profile of both parents. This combination may be useful as a rootstock for the citrus industry in Southeastern Brazil since this somatic hybrid could combine the drought tolerance and vigor of Rangpur lime with the blight tolerance of Caipira sweet orange.Híbridos somáticos de laranja doce (Citrus sinensis L. Osbeck e limão Cravo (C. limonia L. Osbeck foram regenerados após a fusão (polietileno glicol e cultura de protoplastos. Os híbridos somáticos foram confirmados pela análise da morfologia das folhas, determinação do número de cromossomos e marcadores moleculares (RAPD. Todas as plantas analisadas revelaram-se tetraplóides (2n = 4x = 36, possuíam folhas de morfologia intermediária e uma combinação do padrão de bandas de RAPD de ambos os parentais. Esta combinação pode se tornar útil como porta-enxerto para a Região Sudeste da indústria citrícola brasileira. Este híbrido somático potencialmente combinará as características de tolerância à seca e o vigor do limão Cravo com a tolerância ao declínio da laranja Caipira.

  5. Effect of the rootstock and interstock grafted in lemon tree (Citrus limon (L.) Burm.) on the flavonoid content of lemon juice.

    Science.gov (United States)

    Gil-Izquierdo, Angel; Riquelme, María T; Porras, Ignacio; Ferreres, Federico

    2004-01-28

    The grafting of the rootstock with the lemon tree is an agronomical technique used to improve production and/or quality of the fruit. The interstock has been used with different fruit trees to modulate the tree size, fruit production and quality, and the aging of the tree. The lemon trees grafted with interstocks increase their longevity, lemon production and quality; interstocks are also used to decrease the thickness of the trunk at the grafting point. This enlarging of the trunk provokes a decrease of the sap flow. In our study, "Verna" lemon trees were grafted with interstock between the rootstock and the lemon tree to follow the flavonoid content of the lemon juice. The lemon juice was obtained from the lemons collected of the grafted lemon trees. Two types of rootstocks were used: Citrus aurantium L. and Citrus macrophylla L. Seven interstocks from five cultivars of orange tree, one cultivar of lime tree, and one cultivar of tangerine tree were used. "Verna" lemon trees were also grafted directly to the rootstock. The rootstock was more important agronomic factor than the interstock on the total flavonoid content of lemon juice. The interstock grafting had only a small influence on the flavonoid content of the lemon juice, and it modulated the individual flavonoid content. Citrus aurantium L. rootstock and "Berna" and "Washington Navel" interstocks were the most appropriate to graft in the lemon tree. This interstock grafting technique does not increase the flavonoid content of the lemon juice. Regarding the individual flavonoids, the 6,8-di-C-glucosyl diosmetin was the most affected flavonoid by the type of rootstock used. The interstock used is able to alter the individual quantitative flavonoid order of eriocitrin, diosmin, and hesperidin. In addition, the HPLC-ESI/MS(n) analyses provided the identification of two new flavonoids in the lemon juice: Quercetin 3-O-rutinoside-7-O-glucoside and chrysoeriol 6,8-di-C-glucoside (stellarin-2). The occurrence of

  6. Early Performance of Duong Mandarin (Citrus reticulata Blanco on Three Rootstock under Acid Sulfate Soil Fields at Mekong Delta of Vietnam

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    Khoe Thi Le

    2016-01-01

    Full Text Available Abstract About 1.6 billion hectare area of acid sulfate soils is at Mekong Delta of Vietnam, and Duong mandarin fruits are valued for the fresh market due to the easy peeling, attractive flavor, and health and nutritional properties; thereby, the investigation on early performance of Duong mandarin on three rootstock under acid sulfate soil fields (pH below 4 at Mekong Delta of Vietnam was undertaken from 2009 to 2012 for determination of the most promising scion stock combination of Duong mandarin, which introduced to growers for expanding citrus production to increase in income of farmers, and helping to use the sustainable and efficient land resource at acid sulfate soil region of Mekong Delta. Primary results showed that Duong mandarin grafted on Mat orange, Tau lemon and Carrizo citrange were significant differenence in vegetative parameters, fruit yield and quality. It proved that Duong mandarin trees grafted on Tau lemon were better growth and development on acid sulfate soil fields with below 4 pH in soil and water suspension of 1:2.5 ratio as compared to those grafted on Mat orange and Carrizo citrange rootstocks; whereby, that induced trees with 171.48 cm height, 6.65 m3 canopy volume and 51.84 mm trunk diameter, 1.08 scion/ stock ratio in third year after growing. Moreover, Duong mandarin trees grafted on Tau lemon were with spreading growth performance. In regarding to fruit yield and quality, Duong mandarin trees grafted on Tau lemon produced highest fruit yield of 9.21 kg per tree per year in third year after planting, and fruit with 115.30g weight, 8.85 brix juice, thinner and somewhat easy peel rind. 

  7. Colonização micorrízica natural de porta-enxertos de citros em campo Natural mycorrhizal colonization of citrus rootstocks under field conditions

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    Maiara de Souza Nunes

    2006-03-01

    Full Text Available O objetivo deste trabalho foi avaliar, em campo, a colonização micorrízica de porta-enxertos tradicionais e híbridos de citros, do Programa de Melhoramento Genético de Citros, da Embrapa Mandioca e Fruticultura Tropical, selecionados como tolerantes à seca. Raízes finas de citros e amostras de solo foram coletadas em duas épocas do ano. A colonização micorrízica foi elevada nos dois pomares amostrados, com variação entre os genótipos e as épocas de avaliação. Todos os porta-enxertos apresentaram porcentagens elevadas de colonização micorrízica, de 42 a 83%, mesmo em condições de alto teor de fósforo no solo.The objective of this work was to evaluate the mycorrhizal colonization of citrus rootstocks (traditional and hybrid, in the field, selected as tolerant to water deficit by the Citrus Breeding Program of Embrapa Mandioca e Fruticultura Tropical. Fine roots and soil samples were collected in two seasons of the year. The mycorrhizal colonization was high in both citrus orchards sampled, and varied among the genotypes and the seasons of the year. All citrus rootstocks presented high percentages of root colonization, varying from 42 to 83%, even in high soil phosphorous conditions.

  8. Chloride absorption in salt-sensitive Carrizo citrange and salt-tolerant Cleopatra mandarin citrus rootstocks is linked to water use.

    Science.gov (United States)

    Moya, José Luís; Gómez-Cadenas, Aurelio; Primo-Millo, Eduardo; Talon, Manuel

    2003-02-01

    In this work, seedlings of two citrus rootstocks, the salt-tolerant Cleopatra mandarin (Citrus reshni Hort. ex Tan.) and the salt-sensitive Carrizo citrange (Citrus sinensis [L.] Osb. x Poncirus trifoliata [L.] Raf.) were used to study the relationship between chloride and water uptake. The results indicated that net chloride uptake rates in both genotypes were alike and decreased linearly with the time of salinity exposure, although they were more rapidly reduced in the tolerant genotype. In each rootstock, chloride uptake rates paralleled the decreases in transpiration rates. When transpiration was modified, concomitant changes in leaf Cl(-) concentrations were observed. There was a high positive correlation between total chloride content per plant and total water absorbed. In addition, the data indicate that the tolerant genotype "excluded" more chloride, i.e. it absorbed lower amounts of chloride per volume of water. Cleopatra also possessed a less efficient root system for water uptake and a higher shoot-to-root ratio. The results show that, overall, chloride absorption is linked to water use and that further tolerance in Cleopatra is mostly conferred by superior root resistance to Cl(-) uptake. Therefore, it is proposed that chloride absorption and, hence, salt tolerance in citrus depends to a great extent upon water use.

  9. Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

    Energy Technology Data Exchange (ETDEWEB)

    Ros-Ibanez, C.; Robertson, L.; Martinez-Lluch, M. C.; Cano-Garcia, A.; Lacasa-Plasencia, A.

    2014-06-01

    The root-knot nematode (RKN) Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks) has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL) were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively). A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker) behaved like ATL while two others (Terrano and DRO 8801) were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL) confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field. (Author)

  10. Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

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    C. Ros Ibáñez

    2014-02-01

    Full Text Available The root-knot nematode (RKN Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively. A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker behaved like ATL while two others (Terrano and DRO 8801 were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field.

  11. Performance of ‘Okitsu’ satsuma mandarin trees on different rootstocks in Northwestern Parana State

    OpenAIRE

    Zuleide Hissano Tazima; Carmen Silvia Vieira Janeiro Neves; Inês Fumiko Ubukata Yada; Rui Pereira Leite Júnior

    2014-01-01

    In the State of Paraná, citrus production is based mainly on Rangpur lime rootstock, which has good results with the established cultivars. However, research is needed into rootstocks for use with cultivars that remain to be commercially exploited. The objective of this study was to evaluate the vegetative development and yield of ‘Okitsu’ satsuma mandarin plants (Citrus unshiu Marc.), as well as fruit quality, budded on nine rootstocks in the Northwest State of Paraná, Brazil. The orchard wa...

  12. Transcription profiles of boron-deficiency-responsive genes in citrus rootstock root by suppression subtractive hybridization and cDNA microarray.

    Science.gov (United States)

    Zhou, Gao-Feng; Liu, Yong-Zhong; Sheng, Ou; Wei, Qing-Jiang; Yang, Cheng-Quan; Peng, Shu-Ang

    2014-01-01

    Boron (B) deficiency has seriously negative effect on citrus production. Carrizo citrange (CC) has been reported as a B-deficiency tolerant rootstock. However, the molecular mechanism of its B-deficiency tolerance remained not well-explored. To understand the molecular basis of citrus rootstock to B-deficiency, suppression subtractive hybridization (SSH) and microarray approaches were combined to identify the potential important or novel genes responsive to B-deficiency. Firstly four SSH libraries were constructed for the root tissue of two citrus rootstocks CC and Trifoliate orange (TO) to compare B-deficiency treated and non-treated plants. Then 7680 clones from these SSH libraries were used to construct a cDNA array and microarray analysis was carried out to verify the expression changes of these clones upon B-deficiency treatment at various time points compared to the corresponding controls. A total of 139 unigenes that were differentially expressed upon B-deficiency stress either in CC or TO were identified from microarray analysis, some of these genes have not previously been reported to be associated with B-deficiency stress. In this work, several genes involved in cell wall metabolism and transmembrane transport were identified to be highly regulated under B-deficiency stress, and a total of 23 metabolic pathways were affected by B-deficiency, especially the lignin biosynthesis pathway, nitrogen metabolism, and glycolytic pathway. All these results indicated that CC was more tolerant than TO to B-deficiency stress. The B-deficiency responsive genes identified in this study could provide further information for understanding the mechanisms of B-deficiency tolerance in citrus.

  13. Detecção de polimorfismo em porta-enxertos para citros Detection of polimorphism in rootstocks for citrus

    Directory of Open Access Journals (Sweden)

    Renata Aparecida de Andrade

    2007-08-01

    Full Text Available Objetivando a verificação da existência de plântulas originadas de embrião zigótico em viveiros comerciais de mudas cítricas, realizou-se o presente trabalho, utilizando a técnica de fAFLP e quatro espécies de porta-enxertos para citros. Verificou-se uma base genética estreita entre as espécies testadas, além de grande variabilidade entre os materiais, independentemente do viveiro em que foram coletados, o que permite concluir que a seleção visual, comumente realizada nos viveiros, é ineficiente.The purpose of this work was to verify the existence of seedlings originated from the zygotic embryo, in commercial nurseries of citric seedlings. I was used the AFLP technique and four species of citrus rootstocks. It was observed a narrow genetic base among the tested species and also a great variability among the materials, independent of the nursery that they were collected. These results showed that the visual selection, commonly done in the nurseries, is inefficient.

  14. Isolamento e cultivo de protoplastos de porta-enxertos de citros Isolation and growth of citrus rootstock protoplants

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    R.P. de Oliveira

    1995-08-01

    Full Text Available Realizou-se o isolamento e cultivo de protolastos de porta-enxertos de citros das variedades limoeiro Cravo e tangerina Cleópatra. Utilizou-se solução enzimática para a digestão da parede celular de células em suspensão (7 a 10 subcultivos em meio de cultura MT e procedeu-se a purificação criteriosa. O plaqueamento dos protoplastos foi realizado em meio de cultivo KM8p e na molaridade de 0.6 M, sob condições de escuro a 28 ± 1°C, após ajuste para a densidade de 2 x 10s ppts/mL A redução da pressão osmótica do meio de cultivo foi realizada a cada 10 dias na seguinte proporção de meio de cultura KM8p 0.6 M e KM8 (2:1, 1:1, 1:2, 0:3. Com relação aos resultados, obteve-se em média o isolamento de 0.7 x 10(6 ppts / ml de suspensões celulares de tangerina Cleópatra e 0.5 x 1O6 ppts / ml de suspensões de limoeiro Cravo, com uma porcentagem de viabilidade de 86 a 92% para a variedade Cleópatra e de 73 a 80% para o limoeiro Cravo. As divisões celulares começaram a ocorrer por volta do 8° dia após o plaqueamento, sendo obtida uma eficiência inicial de plaqueamento de 9% para a variedade Cleópatra e de 5% para o limoeiro Cravo. Aos 50 dias de cultivo, as colônias foram transferidas para meio semi-sólido MT, onde apresentaram ritmo acelerado de crescimento formando calos.Protoplast isolation and growth of Citrus rootstock v. Cravo lime and Cleópatra mandarin were carried out Enzyme mixture was used to digest cell suspensions 7-10 times, following criterious purification. Protoplast culture was carried out in doplets of semi-solid (agarose 0.6% p/v KM8p medium, in the dark, at 28 ± 1°C following density adjustment to 2 x 10(5 ppts/ml. Osmotic pressure reduction was acomplished for each growth every 10 days with a mixture in equal volumes of KM8p and KM8 medium in ratios of 2:1; 1:1; 1:2 e 0:3. Isolation produced 0.7 x 10(6 ppts/ml for Cleópatra mandarin and 0.5 x 10(6 ppts/ml for Cravo lime, with a viability between 86

  15. Progress in developing Armillaria resistant rootstocks for use with peach

    Science.gov (United States)

    GuardianTM (BY520-9) peach seedling rootstock was released in 1993 to provide a rootstock with superior resistance to peach tree short life (PTSL) which at the time was the number one cause of premature death of peach (Prunus persica L. [Batsch]) trees in the southeastern US. Since that time Guardi...

  16. Reproductive characteristics of citrus rootstocks grown under greenhouse and field environments

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    Divanilde Guerra

    2013-01-01

    Full Text Available The aim of the present study was to evaluate the possible effect of environmental factors on meiosis, meiotic index, pollenviability and in vitro germination of pollen from stock plants of the rootstocks Trifoliate, ‘Swingle’, ‘Troyer’, ‘Fepagro C13’, ‘FepagroC37’ and ‘Fepagro C41’ grown in a protected environment in comparison with stock plants grown in the field. The results showed thatvalues for the characteristics analyzed in 2008, 2009 and 2010 were always higher in the field than in the greenhouse conditions. Inthe field, the average of normal meiotic cells was 60.05%, 44.44% and 60.12%, respectively, and in the greenhouse, 52.75%, 30.95%and 52.82%, respectively. Mean pollen viability in the field was 90.28%, 56.23% and 74.74%, and, in the greenhouse, 64.25%, 41.41%and 66.71%, respectively. As temperature oscillations were higher in the greenhouse than in the field, we suggest that this negativelyaffects the reproductive characteristics analyzed.

  17. Crescimento de híbridos e variedades porta-enxerto de citros sob salinidade = Growth of hybrids and rootstock varieties of citrus under salinity.

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    Pedro Dantas Fernandes

    2011-04-01

    Full Text Available A salinidade da água e do solo afeta o crescimento, o desenvolvimento e a produção de espécies frutíferas, dentre as quais os citros. O uso de porta-enxertos tolerantes pode garantir a sustentabilidade do agronegócio citrícola em tais condições. Assim, estudou-se a sensibilidade à salinidade durante a fase de formação de portaenxertoscompreendendo variedades e híbridos selecionados. O experimento foirealizado em casa-de-vegetação, considerando cinco níveis de salinidade da água de irrigação [testemunha, irrigação com água de abastecimento local, condutividade elétrica da água (CEa de 0,41 dS m-1 e água com CEa de 1,0; 2,0; 3,0 e 4,0 dS m-1] e sete genótipos, utilizando delineamento em blocos casualizados, com cinco repetiçõesem esquema fatorial e quatro plantas úteis por parcela, durante o período de 150 dias. Avaliaram-se variáveis de crescimento e fisiológicas. A redução mais expressiva foi observada na fitomassa seca total da parte aérea com aumento unitário da CEa. Observou-se redução linear no crescimento com aumento da salinidade nos híbridosLVK x LVA-009 e TSK x TRENG-256. Dentre os genótipos avaliados, o limoeiro ‘Volkameriano’ foi o menos sensível ao estresse salino.Water and soil salinity affects the growth, development and production of fructiferous species, such as citrus. The use of tolerant rootstocks can guarantee the agribusiness of citrus under such conditions. Thus, the sensibility to salinity during the phase of rootstock formation of varieties and selected hybrids was studied. The experiment was carried out in a greenhouse, with five levels of irrigation water salinity [control, tap water with electrical conductivity (ECw of 0.41 dS m-1, and water with ECw of 1.0, 2.0, 3.0 and 4.0 dS m-1] and seven genotypes, in a randomized block designand five replications each consisting of four plants, during 150 day period. Growth and physiologic variables were evaluated. Significant effects

  18. Performance of 'Oneco' mandarin on six rootstocks in South Brazil

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    Mateus Pereira Gonzatto

    2011-04-01

    Full Text Available The objective of this work was to assess the effect of six rootstocks on yield, fruit quality, and growth of 'Oneco' mandarin during the first seven harvesting seasons, in Butiá, Rio Grande do Sul State, Brazil. The rootstocks evaluated were: 'Swingle' citrumelo (Citrus paradisi × Poncirus trifoliata, 'Caipira' orange (C. sinensis, 'Troyer' citrange (C. sinensis × P. trifoliata, 'Rangpur' lime (C. limonia, 'Volkamer' lemon (C. volkameriana, and 'Flying Dragon' trifoliata orange (P. trifoliata var. monstrosa. Plants budded onto 'Flying Dragon' had the lowest vegetative development, which indicates the dwarfing characteristics of this rootstock, and had the highest mean production efficiency, despite low yield. Plants grafted on 'Volkamer' lemon and 'Rangpur' lime had the highest alternate bearing. Under the experimental conditions evaluated, the most adequate rootstocks for mandarin 'Oneco' are 'Swingle' citrumelo and 'Troyer' citrange, regarding fruit yield and quality.

  19. Performance of 'Okitsu' Satsuma Mandarin on nine rootstocks

    OpenAIRE

    Zuleide Hissano Tazima; Carmen Silvia Vieira Janeiro Neves; Inês Fumiko Ubukata Yada; Rui Pereira Leite Júnior

    2013-01-01

    Mandarins have become increasingly valued as citrus fruits for the fresh market due to the easy peeling, attractive flavor, and health and nutritional properties. Plant growth and yield, and characteristics of fruits of 'Okitsu' Satsuma mandarin (Citrus unshiu Marc.) trees grafted on nine rootstocks were evaluated in Londrina, northern Paraná, Brazil. The rootstocks were: 'Rangpur' lime (Citrus limonia Osb.); 'Cleopatra' (Citrus reshni hort. ex Tanaka) and 'Sunki' mandarins (Citrus sunki hort...

  20. Poliembrionia e atributos morfológicos de sementes de porta-enxertos de citros Polyembryony and morphological seed traits in citrus rootstocks

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    Fernanda Emilia Vital de Oliveira Duarte

    2013-03-01

    Full Text Available A poliembrionia é um caráter fundamental no melhoramento genético e na multiplicação comercial de porta-enxertos de citros. Este trabalho avaliou as relações entre poliembrionia e diferentes atributos morfológicos de sementes de 12 genótipos de citros selecionados como porta-enxertos. Foram analisadas 50 sementes por genótipo, quanto a massa, altura, largura, número de embriões, taxa de poliembrionia, grau de dificuldade de extração da testa, coloração da semente, estimada por um matiz das duas notas de cores predominantes, e razão de cor, calculada pela divisão entre a menor e a maior nota do matiz. Os resultados foram submetidos à análise de variância, comparando-se as médias pelo teste de Scott-Knott e determinando-se os coeficientes de correlação de Pearson entre as variáveis (P Seed polyembryony is an important trait for breeding and commercial multiplication of citrus rootstocks. This study evaluated relationships of polyembryony with different morphological seed traits of 12 citrus genotypes selected as rootstocks. The following traits were evaluated individually on 50 seeds per genotype: seed mass, height, width and embryo number, polyembryony level, difficulty for seed coat extraction, and seed color, which was estimated by a two-grade scale representing predominant colors on the endosperm. Data was submitted to variance analyses and the means were compared by the Scott-Knott Test (P < 0.05. Pearson's Correlation Coefficients were determined among all variables for all genotypes and individually. Citrus rootstocks had significantly distinct seed traits and could be classified in three polyembryony groups, with three Rangpur lime selections presenting polyembryony lower than 50% and the citrandarins as totally polyembryonic. Other trifoliate hybrids showed low to intermediate polyembryony. Seed coat extraction was more difficult in smaller seeds. For majority of genotypes, the number of embryos in the seed had

  1. Analysis on Acid Tolerance of Several Citrus Rootstock Seedlings%几种柑桔砧木幼苗的耐酸性分析

    Institute of Scientific and Technical Information of China (English)

    方治军; 杨义伶; 黄春辉; 辜青青; 徐小彪

    2011-01-01

    以不同酸性(pH值1.0、2.0、3.0、4.0、5.0和6.0)营养液处理的枳、酸柚、酸橙、卡里佐枳橙、三湖红桔、新干化红、崇义野桔等7种柑桔砧木幼苗为试材,通过酸害症状观测以及酸害指数为指标的聚类分析,对其耐酸性强弱进行鉴定与分析.结果表明,供试柑桔砧木幼苗的耐酸性可分为3类,耐酸性最强的为枳,平均酸害指数为13.33;耐酸性中等的为酸柚、三湖红桔、新干化红、崇义野桔、卡里佐枳橙,平均酸害指数分别为17.33、17.80、17.58、15.11、17.79,这一类的总平均值为17.88;耐酸性最弱的为酸橙,平均酸害指数达26.22.本研究可为柑桔砧木种质改良提供理论依据,同时为柑桔砧木种质资源的合理开发利用提供参考.%Seven citrus rootstock seedlings. Zhi{Poncirus trifoliate (L. ) Raf), Suanyou(Citrus maxima (J. Burman) Merrill), SuanchengCC. Aurantium L,), ZhichengCRuta 'Citrange'), San-huhongju(Citrus reticulate Blanco), Xinganhuahong(C. reticulataXC. Aurantium), and Chongy-iyejuCC. Reticulate Blanco), were treated with nutrient solutions of different pH values to test their tolerance to acid. The results showed that these seedlings could be classified into three groups by their tolerance to acid. P. Trifoliate ( L. ) Raf had the strongest acid tolerance by showing a lowest average acid injury index of 13. 33%. C. Maxima (J. Burman) Merrill, C. Reticulate Blanco, C. reticulataXC. Aurantium, C. Reticulata Blanco, Ruta 'Citrange' showed an median tolerance with an injury index of 17. 33%, 17. 80%, 17. 58%, 15.11 %, 17. 79%, respectively, and the mean acid injury index for this group was 17. 88%. C. Aurantium L. Was the least in acid tolerance for having a high average acid injury index of 26. 22%. The results could be valuable references for citrus root-stock improvement and selecting suitable citrus rootstocks in citrus cultivation.

  2. Sweet orange trees grafted on selected rootstocks fertilized with nitrogen, phosphorus and potassium.

    OpenAIRE

    Quaggio José Antônio; Mattos Junior Dirceu; Cantarella Heitor; Stuchi Eduardo Sanches; Sempionato Otávio Ricardo

    2004-01-01

    The majority of citrus trees in Brazil are grafted on 'Rangpur lime' (Citrus limonia Osb.) rootstock. Despite its good horticultural performance, search for disease tolerant rootstock varieties to improve yield and longevity of citrus groves has increased. The objective of this work was to evaluate yield efficiency of sweet oranges on different rootstocks fertilized with N, P, and potassium. Tree growth was affected by rootstock varieties; trees on 'Swingle' citrumelo [Poncirus trifoliata (L....

  3. Fruit quality of 'Tahiti' lime (Citrus latifolia Tanak grafted on twelve different rootstocks Qualidade de frutos de limeira-ácida 'Tahiti' (Citrus latifolia Tanaka enxertada em doze porta-enxertos

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    Eduardo Sanches Stuchi

    2009-06-01

    Full Text Available In the present work, the effect of twelve rootstocks on fruit quality of the nucellar clone IAC-5 of 'Tahiti' lime, (Citrus latifolia Tanaka and the influence of fruit position on tree in fruit quality was evaluated in the Citrus Experimental Station of Bebedouro (EECB, located in the Bebedouro county, state of São Paulo, Brazil. A 8.0 x 5.0m planting frame was utilized. The evaluated rootstocks were: 'Carrizo' citrange (C. sinensis (L. Osbeck x Poncirus trifoliata (L. Raf.; the hybrids 'Rangpur' lime x 'Swingle' citrumello (C. limonia Osbeck x P. trifoliata Raf and 'Changsha' x 'English Small'(C. sunki Hort. ex Tan. x P. trifoliata Raf.; the mandarins 'Sun Chu Sha Kat' (C. reticulata Blanco and 'Sunki' (C. sunki Hort. ex Tanaka; the 'Rangpur' limes 'Cravo Limeira' and ' Cravo FCAV' (C. limonia Osbeck; the 'Swingle' citrumello (P. trifoliata Raf. x C. paradisi Macf.; the 'Orlando' tangelo (C. reticulata Blanco x C. paradisi Macf. and the trifoliates cvs. 'Rubidoux', 'FCAV' and 'Flying Dragon' (P. trifoliata Raf.. The experiment was arranged in a randomized block design, with twelve treatments, six replicates and one plant per plot. The rootstocks induced differences in fruit quality; however, all the evaluated quality characteristics were within the values considered as normal and acceptable for the variety, constituting good alternative rootstocks for the 'Rangpur' lime. Additionally, the fruit position in the plant (northeastern or southwestern had a significant influence on the external fruit color regardless of the rootstock.No presente trabalho, avaliou-se a influência de doze porta-enxertos sobre a qualidade dos frutos da lima-ácida 'Tahiti' (Citrus latifolia Tanaka, clone 'IAC-5', amostrados em duas posições nas plantas, em experimento conduzido na Estação de Citricultura de Bebedouro, em um pomar de três anos. O espaçamento utilizado foi de 8.0 x 5.0m. Os porta-enxertos utilizados foram: citrangeiro 'Carrizo' (C. sinensis (L

  4. Efecto de cinco porta-injertos sobre la floración, fructificación y maduración de la naranja "frost valencia" Citrus sinensis (L. Obs. en condiciones del CNI-Palmira, Valle del Cauca Effect of five rootstocks in flowering, fructification and maturity in orange "frost Valencia" Citrus sinensis (L. obs. in Palmira, the Cauca Valley

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    Holguín E. Carmen Lucía

    1992-12-01

    Full Text Available

    En el trabajo, realizado en el Instituto Colombiano Agropecuario en Palmira, Valle del Cauca, se consideraron 20 árboles cítricos injertados sobre Citrumelo 4475, Citrus amblycarpa, Citrange yuma, Trifoliado por Ruby Or y Mandarina Cleopatra. Se evaluaron los parámetros desarrollo floral, época e intensidad de la floración, porcentaje de cuajamiento, desarrollo del fruto, proceso de maduración y número y peso de frutos cosechados. La floración de la naranja ocurrió 15-30 días después de una lluvia; la máxima producción de frutos se presentó entre cinco y seis meses después de la máxima precipitación. Los porta-injertos mostraron diferenciase significativas en período de maduración y producción de frutos; no obstante, su potencial productivo fue relativamente similar (17-20%.

    The work was made at Instituto Colombiano Agropecuario, Palmira in the Cauca Valley. It was considered under observation twenty citric trees over five rootstocks: Citrumelo 4475, Citrus amblycarpa, Citrange yuma, Trifoliado por Ruby Or and Mandarina Cleopatra. Flower development, intensity of flower and fruit production, thicken percentage, fruit's development, fruits falled percentage, maduration process and number and weight at harvested fruits was evaluated. Flowering is induced between 15-30 days after any rain. The maximum fruit production was between five and six months after maximum precipitation. The rootstocks are different in maturity epoch, fruit's production; however there were not great differences in potential production (17-20%.

  5. Doses de uréia no crescimento de porta-enxertos de citros produzidos em recipientes Nitrogen fertilization on growth of citrus rootstocks produced in containers

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    Marlon Dutra Degli Esposti

    2004-04-01

    Full Text Available Este trabalho teve como objetivo, determinar a influência de doses de nitrogênio, aplicadas em cobertura na forma de uréia, no crescimento de diferentes porta-enxertos de citros, cultivados em recipientes. O experimento constou de um esquema fatorial (2x5 + (2x5, num delineamento em blocos casualizados, com três repetições, avaliando-se quatro porta-enxertos e cinco doses de uréia que variaram de 0 a 772 mg dm-3 de N no substrato. Foram avaliadas características como o número de folhas, a área foliar, a massa da matéria fresca e a seca de folha, de caule e de raízes. As espécies de porta-enxertos estudadas mostraram diferenças em relação às características de crescimento avaliadas. Os limoeiros apresentaram, durante o período de condução do experimento, as maiores alturas e diâmetro do caule, chegando mais rapidamente ao ponto de enxertia, pelo que foram considerados mais vigorosos que as tangerineiras nesse sistema de cultivo. Os limoeiros tiveram menores exigências de N que as tangerineiras. As doses de N (mg dm-3 de substrato correspondentes às maiores alturas foram 453 para o limoeiro 'Cravo', 431 para o 'Volkameriano', 624 para a tangerineira 'Cleópatra' e 610 para a 'Sunki'. O maior diâmetro foi alcançado com as doses de 455; 433; 543 e 546, respectivamente, para os limoeiros 'Cravo' e 'Volkameriano' e tangerineiras 'Cleópatra' e 'Sunki'.The objective of this study was to determinate urea dose to be applied on citrus rootstocks, and evaluation of the rootstock growths in containers. The factorial scheme (2x5 + (2x5 in a experimental design of randomized blocks was used with three replications, to evaluate four rootstocks, and five urea doses varying from 0 to 772 mg dm-3 in substrate. The following characteristics were evaluated: leaves number, leaf area, weight of the leaf fresh and dry matter, stem weight, and roots weights. Some differences occurred among the studied rootstock species in relation to the

  6. Performance of ‘Okitsu’ satsuma mandarin trees on different rootstocks in Northwestern Parana State

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    Zuleide Hissano Tazima

    2014-10-01

    Full Text Available In the State of Paraná, citrus production is based mainly on Rangpur lime rootstock, which has good results with the established cultivars. However, research is needed into rootstocks for use with cultivars that remain to be commercially exploited. The objective of this study was to evaluate the vegetative development and yield of ‘Okitsu’ satsuma mandarin plants (Citrus unshiu Marc., as well as fruit quality, budded on nine rootstocks in the Northwest State of Paraná, Brazil. The orchard was established at the Experimental Station of the Agronomic Institute of Paraná-IAPAR, Paranavaí, PR, in January 2001. The experimental design was randomized blocks with nine treatments, three replications, and two plants per plot. The rootstocks were Rangpur lime (Citrus limonia Osb., Cleopatra mandarin (Citrus reshni hort. ex Tanaka, C-13 citrange [Citrus sinensis × Poncirus trifoliata orange (L. Raf.], Volkamer lemon (Citrus volkameriana V. Ten. e Pasq., Carrizo citrange [C. sinensis × P. trifoliata (L. Raf.], Sunki mandarin (Citrus sunki hort. ex Tanaka, trifoliate orange [P. trifoliata (L. Raf. ], Swingle citrumelo [Citrus paradisi Macfad. cv. Duncan × P. trifoliata (L. Raf.], and Caipira DAC sweet orange [C. sinensis (L. Osb.]. The largest plant canopy to ‘Okitsu’ was induced by Cleopatra and the lowest by trifoliata, with 37.1 m3 and 9.9 m3, respectively. The highest relationship between scion and rootstock trunk diameter was observed for the plants budded on Swingle. The largest accumulated yields per plant over eight seasons were induced by Volkamer, Rangpur, Caipira DAC, Cleopatra, and Carrizo, ranging from 867.3 to 989.6 kg. These rootstocks also induced the largest fruit mass, along with Sunki, ranging from 173.3 to 188.0 g. Trifoliate induced accumulated production of 52.5% in relation to Rangpur lime. Rangpur, Carrizo, trifoliate, and Swingle induced the largest averages for the ratio, ranging from 10.41 to 10.79. For orchard

  7. Monitoring the viability of citrus rootstocks seeds stored under refrigeration Monitoramento da viabilidade de sementes porta-enxertos de citros armazenados em câmara fria

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    Sérgio Alves de Carvalho

    2013-03-01

    Full Text Available The citrus nursery tree is produced through the bud grafting process, in which rootstock is usually grown from seed germination. The objective of this research was to evaluate, in two dissimilar environmental conditions, the viability and polyembryony expression of five citrus rootstocks seeds stored in different periods under refrigeration. The rootstock varieties evaluated were: Rangpur lime (Citrus limonia Osb. cv. Limeira, Trifoliate orange (Poncirus trifoliata Raf. cv. Limeira, Citrumelo (P. trifoliata x C. paradisi Macf. cv. Swingle, Sunki mandarin (C. sunki Hort. ex Tanaka and Volkamer lemon (C. volkameriana Ten. & Pasq. cv. Catania 2. The experimental design was the randomized blocks in a 11 x 5 x 2 factorial scheme, evaluating from time zero to the tenth month of storage, the five varieties of rootstock in two environments: germination and growth B.O.D type chamber (Biological Oxygen Demand - Eletrolab Brand Model FC 122 at 25 °C; and greenhouse seedbed with partial temperature control (22 °C to 36 °C and humidity control (75-85%. The plot had 24 seeds in four replicates, using trays with substrate in greenhouse and Petri dishes with filter paper in B.O.D. chamber. The seed germination rate and polyembryony expression were evaluated monthly. It was concluded that Trifoliate and Citrumelo Swingle seeds can be stored for up to seven months, while Volkamer lemon, Rangpur lime and Sunki seeds can be stored for up to ten months. The polyembryony expression rate was slightly higher when measured in greenhouse than in B.O.D. chamber and remained stable in both environments until the seventh month, from which dropped sharply. Citrumelo Swingle seeds expressed the highest polyembryony rate (18.8%, followed by Rangpur lime and Volkamer lemon (average value of 13.7%, Sunki (9.4% and Trifoliate (3.2%. Despite some differences among varieties, the viability of rootstock stored seeds can be monitored either in the greenhouse or in B

  8. Desenvolvimento vegetativo de porta-enxertos de citros produzidos em diferentes recipientes Vegetative development of citric rootstocks produced in different containers

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    Paulo de Tarso Lima Teixeira

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o desenvolvimento vegetativo de diferentes porta-enxertos cítricos semeados em bandejas de isopor, em comparação com a semeadura em tubetes cônicos irrigados por capilaridade. O delineamento experimental foi em blocos casualizados, e os tratamentos foram dispostos em parcelas subdivididas, testando os dois tipos de recipientes na parcela principal (tubetes e bandejas de isopor, com volume de substrato de 120cm³, e nas subparcelas três variedades de porta-enxertos cítricos ('Trifoliata' - Poncirus trifoliata [L.] Raf., citrangeiro 'FEPAGRO C37' - Poncirus trifoliata (L. Raf. x Citrus sinensis (L. Osbeck. e tangerineira 'Sunki' - C. sunki hort. ex Tan.. Foram utilizadas 20 plantas por subparcela e três repetições. O desenvolvimento vegetativo, 150 dias após a semeadura, foi superior, de modo geral, nas plantas cultivadas em bandejas. Ao longo do tempo, os porta-enxertos 'FEPAGRO C37' e 'Trifoliata' apresentaram crescimento em altura semelhante entre si e ambos foram superiores à tangerineira 'Sunki'. O citrangeiro 'FEPAGRO C37' foi superior aos demais porta-enxertos em relação ao diâmetro e acúmulo de massa seca.This work aimed to compare the vegetative development of citric rootstocks sowed in isoprene trays on in stiff plastic tubes irrigated by capillarity. The experimental design was a randomized blocks with split plot scheme, testing both containers at the plot (tubes and isoprene trays with 120cm³ of substrate volume, and, in the subplot, three citric rootstock varieties (trifoliate orange - Poncirus trifoliata [L.] Raf., citrange FEPAGRO 'C37' - Poncirus trifoliata (L. Raf. x Citrus sinensis (L. Osbeck.] and tangerine 'Sunki' - C. sunki hort. ex Tan.. Twenty plant per subplot were used and three replications. After 150 days of sowing, plants cultivated in trays showed higher vegetative development. Rootstocks FEPAGRO 'C37' and trifoliate orange presented similar height growth and both

  9. Porta-enxertos para laranjeiras-doces (Citrus sinensis (L. Osb., em Rio Branco, Acre Rootstocks for sweet orange (Citrus sinensis (L. Osb. in Rio Branco, Acre, Brazil

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    Ana da Silva Ledo

    1999-07-01

    Full Text Available O objetivo deste trabalho foi de avaliar o comportamento de sete cultivares de laranjeiras- doces: 'Baia 101', 'Baianinha IAC 79', 'Monte Parnaso', 'Pêra D6', 'Natal 112', 'Valência 27' e 'Aquiri', sobre diferentes porta-enxertos: limão 'Cravo', tangerinas 'Cleópatra' e 'Sunki' e citrange 'Carrizo', nas condições edafoclimáticas de Rio Branco, Acre. O delineamento experimental foi em parcelas subdivididas, com as cultivares nas parcelas, os porta-enxertos nas subparcelas e os quatro anos de avaliação como repetições. As laranjeiras 'Pêra D6', 'Natal 112' e 'Valência 27' apresentaram tendências de maior produção quando enxertadas sobre o limão 'Cravo', e a laranja 'Aquiri' quando enxertada sobre citrange 'Carrizo'. Em relação aos demais porta-enxertos, o limão 'Cravo' mostrou tendências de induzir maior produção/volume de copa e peso médio do fruto, e menor teor de sólidos solúveis totais e acidez total. As laranjas do grupo Baia ('Baia 101', 'Baianinha IAC 79' e 'Monte Parnaso' produziram frutos com baixa percentagem de suco; não são recomendadas para plantio em Rio Branco, AC. Com base nos resultados obtidos, recomendam-se os porta-enxertos citrange 'Carrizo', tangerina 'Cleópatra' e limão 'Cravo' para a laranja 'Aquiri', e o porta-enxerto limão 'Cravo' para as laranjas 'Pêra D6', 'Natal 112' e 'Valência 27'.The objective of this study was to evaluate the behaviour of seven sweet orange cultivars: 'Baia 101', 'Baianinha IAC 79', 'Monte Parnaso', 'Pêra D6', 'Natal 112', 'Valência 27' and 'Aquiri' grafted on different rootstocks: 'Rangpur' lime, 'Cleópatra' and 'Sunki' mandarins, and 'Carrizo' citrange, in the environmental conditions of Rio Branco, Acre, Brazil. The experimental design was a split-plot, with the sweet orange cultivars as the main plots, the rootstocks as the sub-plots, and the four years of evaluation as replications. The 'Pêra D6', 'Natal 112' and 'Valência 27' sweet orange cultivars tended

  10. Nitrogênio e cobre na produção de mudas de citros em diferentes porta-enxertos Nitrogen and copper for citrus nursery production on two different rootstocks

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    Dirceu Mattos Jr.

    2010-01-01

    Full Text Available A citricultura brasileira é uma atividade de destaque na pauta econômica do País. O seu crescimento e manutenção requerem a produção de 15-20 milhões de mudas anualmente. Em vista das características dos viveiros e das variedades porta-enxertos e copas, há a necessidade de se estabelecer um manejo nutricional adequado dessas plantas. O estudo teve o objetivo de avaliar o suprimento de N e Cu e o desenvolvimento e estado nutricional de mudas de laranjeira 'Pêra', sobre porta-enxertos de limoeiro 'Cravo' e tangerineira 'Sunki'. Foram aplicados dois níveis de N = 120 e 240 mg L-1, e quatro de Cu = 0, 5, 10 e 20 mg L-1 (Cu-EDTA via fertirrigação, entre o transplantio de porta-enxertos e a finalização da muda. O porta-enxerto de 'Cravo' possui maior vigor comparado à 'Sunki' com base na produção de massa seca e tamanho das plantas. O maior desenvolvimento das mudas foi obtido com a solução de fertirrigação com 240 mg L-1 de N e 5 a 10 mg L-1 de Cu. Houve efeito depressivo na concentração de 20 mg L-1 de Cu, associado a teores de Cu das folhas de 20 mg kg-1 e das raízes de 50 mg kg-1. Esse prejuízo foi menor com o maior fornecimento de N. Da mesma forma, o pegamento de borbulhas da laranjeira 'Pêra' foi ótimo nas doses intermediárias de Cu. A demanda de Cu foi maior para mudas sobre 'Sunki' na maior dose de N e o excesso desse micronutriente reduziu a absorção de Mn. Os teores de Cu foram maiores nas raízes da porção superior do recipiente de produção das muda, o que coincidiu com a maior adsorção do elemento no substrato, com máximo acima de 300 mg kg-1 de Cu.The citrus industry is an important economical activity in Brazil. The increase and maintenance of citrus groves require the production of 15-20 million nursery plants yearly. Due to the type of nurseries and horticultural characteristics of rootstocks and scions the development of guidelines for best nutrient management of these plants is requiered. This

  11. PERTUMBUHAN MATA TUNAS JERUK KEPROK (CITRUS NOBILIS HASIL OKULASI PADA BERBAGAI MEDIA TANAM DAN UMUR BATANG BAWAH ROUGH LEMON (C. JAMBHIRI

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    Tatiek Kartika Suharsi

    2013-08-01

    Full Text Available The objective of this study was to evaluate keprok (Citrus nobilis budding seed development on various growing media and age of C. jambhiri rootstock. The design of experiment was complete randomized groups with 2 factors and 3 replications. The growing media consisted of soil, charcoal husk, sheep’s manure, compost, and vermi-compost. Rough lemon citrus rootstock’s age were 8, 11, and 14 months. The results showed that the growing media of soil:charcoal husk:compost or vermicompost mixture of [1:1:1] (v:v:v was the best media for increasing keprok bud growing. Rough lemon rootstock of 8 and 11 months age were the best rootstock for keprok. Rough lemon rootstock of 14 month age stimulated growth of keprok bud faster than that of 8 and 11 month age of rootstock.

  12. Developing an understanding of cross-protection by Citrus tristeza virus

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    Svetlana Y Folimonova

    2013-04-01

    Full Text Available Citrus tristeza virus (CTV causes two citrus diseases that have caused devastating losses in global citrus production. The first disease is quick decline of trees propagated on the sour orange rootstock. The second disease is stem pitting, which severely affects a number of economically important citrus varieties regardless of the rootstock used and results in reduced tree growth and vigor as well as in reduced fruit size and quality. Both diseases continue to invade new areas. While quick decline could be effectively managed by the use of resistant and/or tolerant rootstocks, the only means to protect commercial citrus against endemic stem pitting isolates of CTV has been cross-protection with mild isolates of the virus. In some citrus areas cross-protection has been successful and allowed production of certain citrus cultivars despite the presence of severe stem pitting isolates in those regions. However, many other attempts to find isolates that would provide sustained protection against aggressive isolates of the virus had failed. In general, there has been no understanding why some mild isolates were effective and others failed to protect. We have been working on the mechanism of cross-protection by CTV. Recent considerable progress has significantly advanced our understanding of how cross-protection may work in the citrus/CTV pathosystem. As we demonstrated, only isolates that belong to the same strain of the virus cross protect against each other, while isolates from different strains do not. We believe that the results of our research could now make finding protecting isolates relatively straightforward. This review discusses some of the history of CTV cross-protection along with the recent findings and our ‘recipe’ for selection of protecting isolates.

  13. Resposta de porta-enxertos de citros ao déficit hídrico Response of citrus rootstocks to water deficit

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    Elaine Costa Cerqueira

    2004-12-01

    Full Text Available O trabalho foi conduzido em casa de vegetação na Embrapa Mandioca e Fruticultura, em Cruz das Almas - BA, e objetivou-se à identificação de porta-enxertos de citros melhor adaptados ao ecossistema de Tabuleiros Costeiros, quanto a tolerância à seca. Foram estudados os limoeiros 'Cravo' e 'Volkameriano', laranjeira 'Azeda' e os híbridos trifoliados HTR - 051, TSK x CTTR - 002 e TSK x CTTR - 017. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 6 õ 9, com seis genótipos e nove tempos de avaliação. As avaliações foram realizadas na sequência: irrigação, déficit hídrico e irrigação, quando plantas possuíam de 3 a 4 pares de folhas. Foram analisadas as variáveis massas secas da raiz e da parte aérea, o potencial hídrico da planta e a transpiração da folha. Quanto à massa seca da parte aérea, os genótipos limoeiro Volkameriano e laranjeira 'Azeda' apresentaram decréscimos no período de déficit hídrico, sendo que os demais não apresentaram diferenças significativas. Na ausência de irrigação, todos os genótipos apresentaram decréscimos nos seus potenciais hídricos, enquanto apenas os híbridos apresentaram recuperação, mantendo a transpiração. Os híbridos HTR - 051 e TSK x CTTR - 017 apresentaram os melhores desempenhos para todas as variáveis estudadas, mostrando-se mais promissores como porta-enxertos de citros em condições de déficit hídrico.This work was carried out under green house condition at the Embrapa Cassava and Tropical Fruit Crops, Cruz das Almas - Bahia- Brazil, aiming to identify citrus rootstocks better adapted to Coastal Table Land ecosystem as for their drought tolerance. It was studied the Rangpur lime, Volkamer lemon, Sour orange and the trifoliated hybrids HTR - 051, TSK x CTTR - 002, and TSK x CTTR - 017, the last three from the breeding program of the Embrapa Cassava and Tropical Fruits Crops. The experimental design was completely randomized under

  14. Developing cryotherapy to eliminate graft-transmissible pathogens in citrus

    Science.gov (United States)

    This article summarizes research being conducted as part of a project funded by the California Citrus Research Board to develop cryotherapy (freezing buds in liquid nitrogen, and then recovering them) as a viable method for elimination of graft transmissible pathogens from Citrus. There are current...

  15. Sweet orange trees grafted on selected rootstocks fertilized with nitrogen, phosphorus and potassium Laranjas-doce sobre diferentes porta-enxertos adubadas com nitrogênio, fósforo e potássio

    OpenAIRE

    José Antônio Quaggio; Dirceu Mattos Junior; Heitor Cantarella; Eduardo Sanches Stuchi; Otávio Ricardo Sempionato

    2004-01-01

    The majority of citrus trees in Brazil are grafted on 'Rangpur lime' (Citrus limonia Osb.) rootstock. Despite its good horticultural performance, search for disease tolerant rootstock varieties to improve yield and longevity of citrus groves has increased. The objective of this work was to evaluate yield efficiency of sweet oranges on different rootstocks fertilized with N, P, and potassium. Tree growth was affected by rootstock varieties; trees on 'Swingle' citrumelo [Poncirus trifoliata (L....

  16. The development of seed-propagated peach-almond hybrids for use as almond rootstocks (Oral presentation)

    Science.gov (United States)

    Peach-almond hybrids are becoming increasingly popular rootstocks in California almond orchards due to their enhanced vigor as compared with almond propagated on peach root. However, these hybrids are difficult to root without the use of in vitro micropropagation. The development of uniform and vi...

  17. Desenvolvimento do porta-enxerto de tangerineira 'Cleópatra' Development of tangerine tree rootstock 'Cleópatra'

    Directory of Open Access Journals (Sweden)

    Maria do Céu Monteiro da Cruz

    2008-06-01

    Full Text Available Perdas por percolação e lixiviação são evidentes em substratos para produção de mudas cítricas, notadamente na primeira fase, antes da repicagem dos porta-enxertos. Assim, o trabalho foi realizado com o objetivo de avaliar os efeitos do polímero hidroabsorvente e do lithothamnium sobre o desenvolvimento da tangerineira 'Cleópatra' até a repicagem. A semeadura foi realizada em tubetes (50 mL contendo substrato comercial, acrescido dos tratamentos: 2 doses de lithothamnium (0 e 5 g L-1 e 5 doses do polímero (0; 15; 30; 45 e 60 g L-1. Foi utilizado o delineamento inteiramente casualizado, em esquema fatorial 5 x 2, com 4 repetições e sete plantas por parcela. Para avaliar o desenvolvimento das mudas, as seguintes características foram determinadas: comprimento da parte aérea e do sistema radicular (cm, número de folhas por planta e matéria seca da parte aérea e das raízes (mg. A incorporação do polímero hidroabsorvente ao substrato favoreceu o desenvolvimento de porta-enxertos de tangerineira 'Cleopatra' na fase inicial de produção. A dose de polímero utilizada não deve ultrapassar 50 g L-1 para evitar o excesso de umidade no substrato e a deficiência de aeração do sistema radicular. A adição do lithothamnium ao substrato de cultivo proporcionou o melhor desenvolvimento das mudas.Losses by percolating and leaching are evident on substrates for citrus seedling production, notably in the initial phase, until rootstock transplant. The research was carried out with the aim of evaluating the effects of hydro-absorbent polymer and lithothamnium on 'Cleópatra' tangerine tree development until transplant. The sowing was done in stiff plastic tubes (50 mL filled up with commercial substrate and treatments: two doses of lithothamnium (0 and 5 g L-1 and five doses of polymer (0, 15, 30, 45 and 60 g L-1. The experimental design was entirely randomized, in a factor arrangement 5 x 2, with four replications and seven plants by

  18. Desarrollo vegetativo de patrones cítricos cultivados en condiciones de invernadero bajo dos sistemas de riego Vegetative development of citrus seedlings cultivated at greenhouse conditions and submitted to two irrigations systems

    Directory of Open Access Journals (Sweden)

    Gilmar Schäfer

    2006-08-01

    Full Text Available En el presente estudio se evaluó el desarrollo vegetativo de patrones cítricos cultivados en invernadero bajo dos sistemas de riego. El experimento se realizó en la Estação Experimental Agronômica de la Universidade Federal do Rio Grande do Sul, ubicada en Eldorado do Sul, Rio Grande do Sul, Brasil, entre los meses de septiembre de 2003 y abril de 2004, totalizando 225 días de experimentación. El diseño experimental fue de parcelas subdivididas, en factorial 2 x 3, con 4 repeticiones de 22 contenedores cada. En las parcelas principales se evaluaron los sistemas de riego (microaspersión y capilaridad y en las subparcelas los patrones cítricos Poncirus trifoliata (L. Raf., citrangero 'C37' [P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra] y lima 'Rangpur' (C. limonia Osb.. En condiciones de invernadero los patrones cítricos presentan un desarrollo vegetativo más rápido bajo riego por capilaridad respecto a la microaspersión. Los patrones cítricos evaluados presentan desarrollos vegetativos distintos, donde el citrangero 'C37' supera a los demás.The aim of the present work was to evaluate the vegetative development of citrus rootstock seedlings cultivated under greenhouse conditions with two irrigation systems. The experiment was conducted at the Estação Experimental Agronômica , Universidade Federal do Rio Grande do Sul, located in Eldorado do Sul, Rio Grande do Sul, Brazil, from September 2003 to April 2004, totalizing 225 days of experimentation. The experimental design was a split-plot, in a 2x3 factorial, with 4 replications of 22 pots each. In the main plot the irrigation systems was evaluated (micro sprinkler and capillarity and in the split-plot the citrus rootstocks [Trifoliate orange - Poncirus trifoliata (L. Raf., 'C37' citrange - P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra and 'Rangpur' lime - C. limonia Osb.] were evaluated. The main result showed in conditions of greenhouse citrus rootstock seedlings

  19. Clarifying the Effects of Dwarfing Rootstock on Vegetative and Reproductive Growth during Tree Development: A Study on Apple Trees

    Science.gov (United States)

    Costes, E.; García-Villanueva, E.

    2007-01-01

    Background and Aims Despite the widespread use of dwarfing rootstocks in the fruit-tree industry, their impact on tree architectural development and possible role in the within-tree balance between growth and flowering are still poorly understood, in particular during the early years of growth. The present study addressed this question in apple trees, through a detailed analysis of shoot populations, i.e. both vegetative and flowering shoots, during tree development. Methods Architectural databases were constructed for trees of two cultivars that were either own-rooted or grafted on dwarfing rootstock. Within-tree shoot demographics and annual shoot characteristics, i.e. their dimensions, number of laterals and flowering, were observed from the first to the fifth year of growth and compared among scion/root system combinations. Key Results Differences in axis demographics appeared among scion/root system combinations after the second year of growth. Differences were found (a) in the number of long axes and (b) the number of medium axes. Dwarfing rootstock reduced the total number of axes developed in a tree, and this reduction resulted from proportionally more medium axes and spurs than long axes. The life span of spurs was also shortened. These phenomena appeared after an increase in flowering that started in the second year of growth and involved both axillary and terminal positions. Flowering regularity was also increased in grafted trees. Conclusions These results confirm that the number of long shoots and flowering potential depend on the cultivar. They indicate that tree architectural plasticity in response to its root system mainly derives from the number of medium shoots developed and follows priorities within the whole tree axis population. There was also evidence for dwarfing rootstock involvement in adjusting the flowering abundance and that differences in flowering occurrence take precedence over those regarding vegetative growth during tree development

  20. Development of a full-genome cDNA clone of Citrus leaf blotch virus and infection of citrus plants.

    Science.gov (United States)

    Vives, María Carmen; Martín, Susana; Ambrós, Silvia; Renovell, Agueda; Navarro, Luis; Pina, Jose Antonio; Moreno, Pedro; Guerri, José

    2008-11-01

    Citrus leaf blotch virus (CLBV), a member of the family Flexiviridae, has a ~9-kb single-stranded, positive-sense genomic RNA encapsidated by a 41-kDa coat protein. CLBV isolates are associated with symptom production in citrus including leaf blotching of Dweet tangor and stem pitting in Etrog citron (Dweet mottle disease), and some isolates are associated with bud union crease on trifoliate rootstocks, but Koch's postulates for this virus were not fulfilled. A full-genome cDNA of CLBV isolate SRA-153, which induces bud union crease, was placed under the T7 promoter (clone T7-CLBV), or between the 35S promoter and the Nos-t terminator, with or without a ribozyme sequence downstream of the CLBV sequence (clones 35SRbz-CLBV and 35S-CLBV). RNA transcripts from T7-CLBV failed to infect Etrog citron and Nicotiana occidentalis and N. benthamiana plants, whereas agro-inoculation with binary vectors carrying 35SRbz-CLBV or 35S-CLBV, and the p19 silencing suppressor, caused systemic infection and production of normal CLBV virions. Virus accumulation was similar in citron plants directly agro-infiltrated, or mechanically inoculated with wild-type or 35SRbz-CLBV-derived virions from Nicotiana, and the three sources incited the symptoms characteristic of Dweet mottle disease, but not bud union crease. Our results show that (1) virions derived from an infectious clone show the same replication, movement and pathogenicity characteristics as the wild-type CLBV; (2) CLBV is the causal agent of Dweet mottle disease but not of the bud union crease syndrome; and (3) for the first time an RNA virus could be successfully agro-inoculated on citrus plants. This infectious clone may become a useful viral vector for citrus genomic studies.

  1. Balanço hídrico no solo para porta-enchertos de citros em ecossistema de tabuleiro costeiro Water balance in soil for citrus rootstocks in the brazilian coastal tableland ecosystem

    Directory of Open Access Journals (Sweden)

    Fernando Luis Dultra Cintra

    2000-04-01

    Full Text Available A má distribuição das chuvas e a existência de camadas coesas em muitos solos dos tabuleiros promovem, muitas vezes, alterações importantes no regime hídrico do solo e nas taxas de evapotranspiração das culturas exploradas nesse ecossistema. Objetivou-se, com este trabalho, conhecer, através do balanço hídrico, como esses processos ocorrem e, também, contribuir para o estabelecimento de práticas de manejo visando ao melhor uso das reservas de água no solo. Todos os componentes do balanço foram medidos, à exceção da evapotranspiração, que foi calculada. Os resultados obtidos permitiram concluir que a maior demanda hídrica da laranjeira aconteceu nos meses de outubro e novembro e que, com base na taxa de evapotranspiração, a Tangerina Cleópatra (Citrus reshni Hort. ex Tan. foi o porta-enxerto menos adaptado e o Limão Cravo (Citrus limonia Osbeck o que apresentou as melhores características de adaptação à área estudada.The irregular rain distribution and the existence of hardened layers in several soils of the tablelands promote, sometimes, important changes in the soil water regime and in the rates of evapotranspiration of the crops utilized in that ecosystem. The objective of this work was to know, by means of the water balance, how these processes occur in the studied area and to contribute to the establishment of management practices in order to make better use of the soil water. All components of the equations were measured, with exception of the evapotranspiration which was calculated. According to the results, it could be concluded that the orange tree had the maximum water consumption during the months of October and November and that, in terms of the rootstocks during these periods of great water consumption, the "Tangerina Cleópatra" (Citrus reshni Hort. former Tan. was the less adapted and the "Limão Cravo" (Citrus limonia Osbeck presented the best adaptation characteristics to the studied area.

  2. Performance of 'Oneco' mandarin on six rootstocks in South Brazil.

    OpenAIRE

    Mateus Pereira Gonzatto; Alisson Pacheco Kovaleski; Eduardo Cesar Brugnara; Roberto Luis Weiler; Ivar Antônio Sartori; Jurandir Gonçalves de Lima; Renar João Bender; Sergio Francisco Schwarz

    2011-01-01

    The objective of this work was to assess the effect of six rootstocks on yield, fruit quality, and growth of 'Oneco' mandarin during the first seven harvesting seasons, in Butiá, Rio Grande do Sul State, Brazil. The rootstocks evaluated were: 'Swingle' citrumelo (Citrus paradisi × Poncirus trifoliata), 'Caipira' orange (C. sinensis), 'Troyer' citrange (C. sinensis × P. trifoliata), 'Rangpur' lime (C. limonia), 'Volkamer' lemon (C. volkameriana), and 'Flying Dragon' trifoliata orange (P. trifo...

  3. Performance of 'Oneco' mandarin on six rootstocks in South Brazil

    OpenAIRE

    Gonzatto,Mateus Pereira; Kovaleski, Alisson Pacheco; Brugnara, Eduardo Cesar; Weiler,Roberto Luis; Sartori, Ivar Antonio; Lima, Jurandir Goncalves de; Bender, Renar João; Schwarz,Sergio Francisco

    2011-01-01

    The objective of this work was to assess the effect of six rootstocks on yield, fruit quality, and growth of 'Oneco' mandarin during the first seven harvesting seasons, in Butiá, Rio Grande do Sul State, Brazil. The rootstocks evaluated were: 'Swingle' citrumelo (Citrus paradisi × Poncirus trifoliata), 'Caipira' orange (C. sinensis), 'Troyer' citrange (C. sinensis × P. trifoliata), 'Rangpur' lime (C. limonia), 'Volkamer' lemon (C. volkameriana), and 'Flying Dragon' trifoliata orange (P. trifo...

  4. Caracterização de híbridos de Poncirus trifoliata e de outros porta-enxertos de citros no Estado da Bahia Characterization of Poncirus trifoliata hybrids and other citrus rootstocks in the State of Bahia

    Directory of Open Access Journals (Sweden)

    Orlando Sampaio Passos

    2006-12-01

    Full Text Available Estudos visando à caracterização de híbridos de Poncirus trifoliata (L. Raf. e porta-enxertos tradicionais foram realizados no sentido de se conhecer o seu comportamento nas condições tropicais do Estado da Bahia. Foram tomadas medidas de altura, diâmetro e peso de frutos, número de sementes por fruto e por quilo, bem como contagem de embriões, taxa de poliembrionia, percentagens de germinação e de vingamento de borbulhas na enxertia, em mais de 34 acessos, a maioria introduzida da Califórnia - EUA. Os dados obtidos estimulam o uso de alguns híbridos de trifoliata, como os das tangerineiras 'Cleópatra' (Citrus reshni hort. ex Tanaka e 'Sunki' (C. sunki hort. ex Tanaka com os trifoliatas 'Swingle' e 'English'.Studies on characterization of trifoliate hybrids and traditional rootstocks were accomplished in order to know their behavior under tropical conditions in the State of Bahia. Measurements of the height, diameter and weight of the fruits were taken, number of seeds per fruit and per kilo were counted, as well as number of embryos, polyembryony and germination rate and grafting in 34 accessions, mostly introduced from California, USA. The obtained data encourage the use of some trifoliate hybrids, as those from crosses between 'Cleopatra' mandarin (C. reshni hort. ex Tanaka and 'Sunki' mandarin (C. sunki hort. ex Tanaka with 'Swingle' and 'English' trifoliate.

  5. Learning to fight a fly : developing citrus IPM in Bhutan

    NARCIS (Netherlands)

    Schoubroeck, van H.J.

    1999-01-01

    The chinese citrus fly is one of the key pests in Bhutanese mandarin orchards that lays eggs in developing fruit that cause pre-mature fruit drop. In this study it is used as a "model subject" to explore the integration of technical, social and administrative domains of knowledge. The confinement of

  6. A escarificação química e o desenvolvimento inicial de porta-enxertos cítricos Chemical scarification and initial development of citric rootstocks

    Directory of Open Access Journals (Sweden)

    Paulo de Tarso Lima Teixeira

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar a emergência e o desenvolvimento vegetativo de diferentes porta-enxertos cítricos provenientes de sementes escarificadas quimicamente. O delineamento experimental adotado foi o de blocos ao acaso, em esquema fatorial 2 x 4 (escarificação x porta-enxertos, com três blocos, e cada parcela constituída por 20 tubetes. O tratamento químico realizado nas sementes constituiu-se de uma solução composta por 0,5 L de hipoclorito de sódio (NaClO a 12%, 3 mL de ácido clorídrico (HCl e 20 g de hidróxido de sódio comercial (NaOH, dissolvidos em 1L de água. Os porta-enxertos avaliados foram o 'Trifoliata' (Poncirus trifoliata [L.] Raf., o citrangeiro 'C37' [Poncirus trifoliata (L. Raf. x Citrus sinensis (L. Osbeck.], o citrumeleiro 'Swingle' [P. trifoliata x (L. Raf. x C. paradisi Macf.] e a tangerineira 'Sunki' (C. sunki hort. ex Tan.. Os porta-enxertos 'C37' e 'Trifoliata' beneficiaram-se da escarificação química do tegumento, apresentando maior velocidade e taxa de emergência das plântulas e maior taxa de emergência, aos 45 dias após a semeadura (DAS. Por outro lado, os porta-enxertos 'Swingle' e 'Sunki' apresentaram uma redução da emergência das plântulas, quando suas sementes foram submetidas à escarificação química do tegumento. As plantas de 'C37' e 'Trifoliata', oriundas de sementes escarificadas, apresentaram diâmetro ao nível do colo e acúmulo de massa seca significativamente superiores aos 150 DAS, em relação às plantas oriundas de sementes com o tegumento intacto.The aim of this study was to evaluate emergence and vegetative development of different citric rootstocks derived from chemically scarified seeds. A randomized block design was used in a 2x4 factorial (scarification x rootstocks with three blocks. Each plot had 20 plastic tubes. The seed chemical treatment was a solution composed by 0.5 L of 12 % sodium hypochlorite (NaClO, 3 mL of chloridric acid (HCl and 20g of

  7. Production of interstocked 'Pera' sweet orange nursey trees on 'Volkamer' lemon and 'Swingle' citrumelo rootstocks

    Directory of Open Access Journals (Sweden)

    Girardi Eduardo Augusto

    2006-01-01

    Full Text Available Incompatibility among certain citrus scion and rootstock cultivars can be avoided through interstocking. 'Pera' sweet orange (Citrus sinensis L. Osbeck nursery tree production was evaluated on 'Swingle' citrumelo (Poncirus trifoliata (L. Raf x Citrus paradisi Macf and 'Volkamer' lemon (Citrus volkameriana Pasquale incompatible rootstocks, using 'Valencia' and 'Hamlin' sweet oranges (Citrus sinensis L. Osbeck, 'Sunki' mandarin (Citrus sunki Hort. ex Tanaka, and 'Cleopatra' mandarin (Citrus reshni Hort. ex Tanaka as interstocks. Citrus nursery trees interstocked with 'Pera' sweet orange on both rootstocks were used as control. 'Swingle' citrumelo led to the highest interstock bud take percentage, the greatest interstock height and rootstock diameter, as well as the highest scion and root system dry weight. Percentage of 'Pera' sweet orange dormant bud eye was greater for plants budded on 'Sunki' mandarin than those budded on 'Valencia' sweet orange. No symptoms of incompatibility were observed among any combinations of rootstocks, interstocks and scion. Production cycle can take up to 17 months with higher plant discard.

  8. Characterizing the citrus cultivar Carrizo genome through 454 shotgun sequencing.

    Science.gov (United States)

    Belknap, William R; Wang, Yi; Huo, Naxin; Wu, Jiajie; Rockhold, David R; Gu, Yong Q; Stover, Ed

    2011-12-01

    The citrus cultivar Carrizo is the single most important rootstock to the US citrus industry and has resistance or tolerance to a number of major citrus diseases, including citrus tristeza virus, foot rot, and Huanglongbing (HLB, citrus greening). A Carrizo genomic sequence database providing approximately 3.5×genome coverage (haploid genome size approximately 367 Mb) was populated through 454 GS FLX shotgun sequencing. Analysis of the repetitive DNA fraction indicated a total interspersed repeat fraction of 36.5%. Assembly and characterization of abundant citrus Ty3/gypsy elements revealed a novel type of element containing open reading frames encoding a viral RNA-silencing suppressor protein (RNA binding protein, rbp) and a plant cytokinin riboside 5′-monophosphate phosphoribohydrolase-related protein (LONELY GUY, log). Similar gypsy elements were identified in the Populus trichocarpa genome. Gene-coding region analysis indicated that 24.4% of the nonrepetitive reads contained genic regions. The depth of genome coverage was sufficient to allow accurate assembly of constituent genes, including a putative phloem-expressed gene. The development of the Carrizo database (http://citrus.pw.usda.gov/) will contribute to characterization of agronomically significant loci and provide a publicly available genomic resource to the citrus research community.

  9. Desenvolvimento e produtividade da tangerina "Fairchild" sobre quatro porta-enxertos Development and yield of 'Fairchild' mandarin on four rootstocks

    Directory of Open Access Journals (Sweden)

    Erick Espinoza-Núñez

    2008-09-01

    Full Text Available Neste trabalho foi avaliado o desenvolvimento vegetativo, a produção e a qualidade de frutos da tangerina "Fairchild" [(tangerina "Clementina" (C. clementina Hort. ex. Tan. x tangelo "Orlando" (C. paradisi Macf. x C. reticulata Blanco] sobre os porta-enxertos limão "Cravo" (C. limonia Osbeck, citrumelo "Swingle" (P. trifoliata Raf. x C. paradisi Macf., tangerina "Cleópatra" (C. reshni Hort. ex Tan. e tangelo "Orlando" (C. reticulata Blanco x C. paradisi Macf. em Bebedouro, SP, em experimento instalado em 1997. Plantas enxertadas em citrumelo "Swingle" apresentaram menor porte, maior produção acumulada de frutos nas safras 2005 e 2006, maior eficiência de produção (kgm-3 e menor índice de alternância de produção. A qualidade dos frutos não foi influenciada em função dos porta-enxertos. O citrumelo "Swingle" foi considerado cultivar porta-enxerto adequado para utilização com tangerina "Fairchild".The vegetative development, fruit yield and quality of 'Fairchild' mandarin [('Clementine' mandarin (C. clementina Hort. ex. Tan. x 'Orlando' tangelo (C. paradisi Macf. x C. reticulata Blanco] was evaluated on 'Rangpur' lime (C. limonia Osbeck, 'Swingle' citrumelo (P. trifoliata Raf. x C. paradisi Macf., 'Cleopatra' mandarin (C. reshni Hort. ex Tan. and 'Orlando' tangelo (C. reticulata Blanco x C. paradisi Macf. rootstocks in an experiment installed in Bebedouro, SP, Brazil in 1997. 'Fairchild' trees budded on 'Swingle' citrumelo were smaller, had higher cumulative yield in 2005 and 2006 seasons, higher yield efficiency (kgm-3, showed lower alternate bearing index. Fruit quality was not affected by the rootstock. 'Swingle' citrumelo was considered an adequate rootstock for 'Fairchild' mandarin.

  10. Oxidative stress associated with rootstock-scion interactions in pear/quince combinations during early stages of graft development.

    Science.gov (United States)

    Irisarri, Patricia; Binczycki, Piotr; Errea, Pilar; Martens, Helle Juel; Pina, Ana

    2015-03-15

    Exposing a plant to stress situations, such as grafting, generally triggers antioxidant defense systems. In fruit tree grafting, quince (Cydonia oblonga) is widely used as a rootstock for pear (Pyrus communis L.), but several economically important pear cultivars are incompatible with available quince rootstocks. In this study, grafts were established using an in vitro callus graft system mimicking the events taking place in fruit trees. In vitro grown callus from pear [P. communis L. cv. 'Conference' (Co) and cv. 'William' (Wi)] and quince (C. oblonga Mill. clone 'BA29') was used to establish the compatible homografts 'Co/Co', 'Wi/Wi' and 'BA29/BA29', the compatible heterograft 'Co/BA29' and the incompatible heterograft 'Wi/BA29'. The main objective was to determine whether specific isoforms of genes involved in oxidative stress [superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT)] are differentially expressed at the graft interface from compatible and incompatible unions throughout 3 weeks after grafting. Reactive oxygen species (ROS) levels and programmed cell death were also evaluated in the course of graft development. Genes differentially expressed between compatible and incompatible heterografts were identified. Transcript levels of six antioxidant genes (SOD1, SOD3, APX3, APX6, CAT1 and CAT3) were down-regulated 10 days after grafting (DAG) in the incompatible heterograft in comparison to the compatible one. Likewise, SOD enzymatic activities were significantly higher at 1 and 10 days after wounding in the compatible cultivar 'Co' than in the incompatible one 'Wi'. These findings, together with live cell imaging of ROS-specific probes, ultrastructural mitochondrial changes and DNA fragmentation related to apoptotic processes, give indications that within incompatible rootstock/scion interfaces, either the level of ROS is increased or there is a less efficient detoxification system.

  11. Organic Acid Concentrations and the Relative Enzymatic Changes During the Development of the Citrus Fruits

    Institute of Scientific and Technical Information of China (English)

    LUO An-cai; YANG Xiao-hong; DENG Ying-yi; LI Chun-fan; XIANG Ke-shu; LI Dao-gao

    2003-01-01

    Seasonal changes in enzyme activities and citrate concentration during the development of citrus fruits were investigated. The result showed that the organic acid concentrations reached a peak in the 100 - 130days after anthesis and gradually declined during later stages of fruit maturation in most varieties of citrus,but declined only slightly thereafter in lemon [Citrus lin on (L.) Burm]; there is no relation between the activity of citrate synthetase(CS) and the different acid concentration in different citrus fruits; the increase of the activity of the cytosolic aconitase in the late period of the development of citrus fruits accelerated the degradation of citric acid in citrus fruits; the higher the activity of phosphoenolpyruvate carboxylase(PEPC) and the ratio of NAD-dependent isocitrate hydrogenase(PEPC/NAD-IDH- ), the more the concentrations of organic acids in citrus fruit.

  12. Fruit quality properties of some virus-free grapefruit varieties grafted on different rootstocks

    Directory of Open Access Journals (Sweden)

    Şenay KURT

    2014-12-01

    Full Text Available Sanitation studies against virus and virus like diseases causing large economic losses in citrus plantations in Turkey were begun at Antalya Citrus Research Institute in 1988. As a result of the study, some virus-free grapefruit varieties (Redblush, Rio Red, Ray Ruby, Henderson, Star Ruby and Marsh Seedless budded on Local sour orange and Troyer citrange rootstocks were planted at breeding parcel in 1995. Effects of rootstocks on fruit quality properties were investigated in these grapefruit varieties. Local sour orange and Troyer citrange affected similarly on the fruit quality of grapefruit cultivars. It could be suggested that these rootstocks could be recommended for grapefruit growing.

  13. Parentais femininos monoembriônicos na obtenção de porta-enxertos híbridos de citros The use of female monoembryonic parents to obtain citrus rootstocks hybrids

    Directory of Open Access Journals (Sweden)

    Walter dos Santos Soares Filho

    2008-03-01

    Full Text Available Visando a evitar os efeitos da poliembrionia, os quais dificultam a distinção entre indivíduos híbridos e aqueles de origem materna (nucelares. O Programa de Melhoramento Genético de Citros da Embrapa Mandioca e Fruticultura Tropical selecionou híbridos monoembriônicos, com potencial de geração de novos porta-enxertos, e utilizou-os como parentais femininos em polinizações abertas. Esses parentais foram: trifoliados HTR-001; HTR-002; HTR-005; HTR-037; HTR-073 e HTR-135, além de LCR (limoeiro 'Cravo' Citrus limonia x LRF (limoeiro 'Rugoso da Flórida' C. jambhiri - 005. As progênies de meios-irmãos obtidas compreenderam, respectivamente, 364; 55; 12; 58; 51; 551 e 59 seedlings (plantas oriundas de sementes zigóticos. Os híbridos dentro de progênies foram extremamente variáveis quanto à altura da planta e diâmetro do caule, também apresentando diferenças na presença de ramificações, formato, cor e textura do limbo foliar e tamanho de espinhos. A progênie mais vigorosa relacionou-se ao parental HTR-073, dando-se o contrário com aquela relativa ao híbrido LCR x LRF-005. Este trabalho indica que, em citros, a utilização de parentais femininos monoembrônicos em cruzamentos abertos constitui método simples e fácil de obtenção de híbridos.Seeking to avoid the effects of polyembryony, that difficult the identification of hybrids and individuals of maternal origin (nucellar, the Citrus Breeding Program of Embrapa Cassava & Tropical Fruits selected monoembryonic hybrids with potential of generating new rootstocks. Thus, the trifoliate hybrids HTR-001, HTR-002, HTR-005, HTR-037, HTR-073 and HTR-135, besides LCR ('Rangpur' lime Citrus limonia x LRF ('Florida' rough lemon C. jambhiri - 005 were used as female parents in open pollinations design. The half-sibling progenies obtained were, respectively, 364; 55; 12; 58; 51; 551 and 59 zygotic seedlings. The hybrids inside progenies were extremely variable as regards the height

  14. Occurrence, molecular characterisation, and pathogenicity of Neoscytalidium dimidiatum on Citrus in Italy

    NARCIS (Netherlands)

    Polizzi, G.; Aiello, D.; Castello, I.; Vitale, A.; Groenewald, J.Z.; Crous, P.W.; Gentile, A.; La Malfa, S.

    2011-01-01

    During 2008 and 2009, a new disease was noticed in eastern Sicily (Italy) in two re-grafted citrus orchards (Citrus sinensis (L.) Osbeck) on sour orange rootstock. Symptoms consisted of blight of vigorously growing shoots and a sooty canker on shoots and rootstock trunks. A Scytalidium-like fungus w

  15. Occurrence, molecular characterisation, and pathogenicity of Neoscytalidium dimidiatum on citrus in Italy

    NARCIS (Netherlands)

    Polizzi, G.; Aiello, D.; Castello, I.; Vitale, A.; Groenewald, J.Z.; Crous, P.W.

    2011-01-01

    During 2008 and 2009, a new disease was noticed in eastern Sicily (Italy) in two re-grafted citrus orchards (Citrus sinensis (L.) Osbeck) on sour orange rootstock. Symptoms consisted of blight of vigorously growing shoots and a sooty canker on shoots and rootstock trunks. A Scytalidium-like fungus w

  16. Biological Indexing of Graft Transmissible Diseases of Citrus

    Science.gov (United States)

    Biological indexing for the detection of graft transmissible diseases of citrus is essential for maintaining a citrus certification program. Many of the graft transmissible diseases of citrus are harbored as latent infections in the scions, but when propagated on a susceptible rootstock that allow...

  17. Influência de fitorreguladores e nitrato de potássio na germinação de sementes e no crescimento de porta-enxerto de Citrus amblycarpa Influence of growth regulators and potassium nitrate on Citrus amblycarpa seed germination and growth of rootstocks

    Directory of Open Access Journals (Sweden)

    S. Leonel

    1994-08-01

    Full Text Available Foram avaliados os efeitos de fitorreguladores (giberelinas e citocininas e nitrato de potássio (KNO3, na germinação de sementes e na promoção do crescimento de "seedlings" do porta-enxerto 'Nasnaran' (Citrus amblycarpa Ochese. Realizou-se primeiramente o experimento em germinador, contendo papel de filtro umedecido com água destilada e gerbox, como meio para a germinação das sementes. Os tratamentos foram realizados mediante imersão das sementes, em soluções preparadas com os fítorreguladores e KNO3, durante 24 horas. Através dos resultados obtidos, concluiu-se que o tratamento com 100 mg/1 de GA4 + GA7 + fenilmetilaminopurina, apresentou a maior porcentagem de germinação (88%, num tempo médio de 21 dias. Tomando como base o resultado do germinador, sementes de Citrus amblycarpa foram semeadas em canteiros e quando as plantas atingiram a altura de 6,0 cm receberam 2 pulverizações com 0; 50; 100 e 150 mg/1 de GA4 + GA7 + fenilmetilami-nopurina, com intervalo de 21 dias. Avaliou-se a matéria seca total, caule e folhas, área foliar e altura das plantas, sendo que a análise desses parâmetros mostrou que o GA4 + GA7 + fenilmetUaminopurina na concentração de 50 mg/1 foi o tratamento que apresentou os melhores resultados.The effects of growth regulators (gibberellins and cytokmins and potassium nitrate were evaluated for Citrus amblycarpa seed germination and rootstock growth. First an experiment was performed in a germinator, using as a medium for seed germination filter paper wetted with distiled water. Seeds were treated with growth regulators and potassium nitrate during 24 hours. The results obtained indicate that the treatment of 100 mg/1 of GA4 + GA7 + phenylmethylaminepurine was the best, with a percentage of germination of 88% at 21 days. Based on the results obtained in the germinator, seeds of Citrus amblycarpa were seeded in soil and when the seedlings were 6 cm high they were sprayed with 50 mg/1 of GA4 + GA7

  18. Produção de frutos e incidência de cancro cítrico em laranjeiras "Monte Parnaso" enxertadas sobre sete porta-enxertos Fruit production and incidence of citrus canker lesions on "Monte Parnaso" navel orange budded on seven rootstocks

    Directory of Open Access Journals (Sweden)

    Bernadete Reis

    2008-06-01

    Full Text Available Porta-enxertos de citros podem exercer influência sobre a produção de frutos e suscetibilidade das plantas ao cancro cítrico. Este trabalho objetivou selecionar porta-enxertos que induzam elevado índice de produtividade e menor suscetibilidade das copas de laranjeiras-de-umbigo "Monte Parnaso"(Citrus sinensis à bactéria Xanthomonas axonopodis pv. citri, causadora do cancro cítrico (CC. O experimento foi desenvolvido em um pomar experimental com 10 anos de idade, plantado em espaçamento de 2,5 x 6,0m, no município de Butiá, no Estado do Rio Grande do Sul. O delineamento experimental foi em blocos ao acaso, com sete tratamentos e quatro repetições, usando duas plantas por parcela. Os tratamentos constaram dos seguintes porta-enxertos: limoeiros "Cravo" (C. limonia e "Volkameriano" (C. volkameriana., trifoliata "Flying Dragon" (Poncirus trifoliata., laranjeira "Caipira" (C. sinensis, citrangeiro "Troyer" (C. sinensis x P. trifoliata, tangerineira "Sunki" (C. sunki. e citrumeleiro "Swingle" (C. paradisi x P. trifoliata. Os parâmetros avaliados foram: incidência de CC em folhas e frutos em toda a planta e em ramos previamente selecionados, em diversas épocas. Verificou-se que as plantas enxertadas sobre citrumeleiro "Swingle" apresentaram o maior índice de produtividade e, à semelhança do "Flying Dragon", a menor incidência de CC, tanto nas folhas como nos frutos. Além disso, verificou-se também que as plantas enxertadas sobre os limoeiros "Cravo" e "Volkameriana", apesar de produzirem as mais elevadas cargas de frutos, foram as mais suscetíveis ao CC.Citrus rootstocks can exert some influences on fruit production and susceptibility of the plants to citrus canker (CC. This research was performed aiming to select rootstocks which induce higher productivity index and lower susceptibility of 'Monte Parnaso' navel orange (Citrus sinensis trees to the bacteria Xanthomonas axonopodis pv. citri. The research was carried out in an

  19. Rootstocks: diversity, domestication and impacts on shoot phenotypes

    Science.gov (United States)

    Grafting is an ancient agricultural practice that joins the root system (rootstock) of one plant to the shoot system (scion) of another individual. It is most commonly employed in woody perennial crops such as Apples, Grapes, and Citrus species to shorten scion juvenile stage length, facilitate clo...

  20. Produção de fitomassa em genótipos de citros submetidos a estresse hídrico na formação do porta-enxerto Dry matter production of citrus genotypes under water stress during the rootstock formation

    Directory of Open Access Journals (Sweden)

    Janivan F. Suassuna

    2012-12-01

    Full Text Available Devido à importância dos porta-enxertos no sucesso da citricultura e sua influência na tolerância a fatores de estresse, desenvolveu-se este estudo com o objetivo de avaliar a tolerância de porta-enxertos de citros ao estresse hídrico. Estudaram-se dois fatores: manejo hídrico ('sem estresse' e 'com estresse', neste último caso, com irrigação baseada em 50 e 25% da capacidade de campo e porta-enxerto (10 genótipos de citros fornecidos pelo Programa de Melhoramento Genético de Citros da Embrapa Mandioca e Fruticultura Tropical. Adotou-se o delineamento em blocos casualizados com três repetições e 15 plantas por parcela; avaliaram-se as fitomassas da parte aérea, das folhas, do caule, da raiz e total, além da relação raiz/parte aérea, razão de peso foliar e rendimento relativo. O déficit hídrico reduziu a fitomassa total e incrementou, em alguns porta-enxertos, a relação raiz/parte aérea. A fitomassa foliar é a variável mais afetada, negativamente, nos porta-enxertos de citros sob deficiência hídrica. O genótipo 'TSKFL x CTTR-017' possui capacidade de adaptação ao déficit hídrico, com potencial promissor para uso em áreas sujeitas às condições de seca.Knowing the importance of the rootstocks for the success of the citrus crop and its influence on tolerance to stress factors, this study was conducted in order to evaluate tolerance of citrus rootstocks to water stress studying two factors: water management ('without stress' and 'under stress' and in this latter case, the irrigation was based on 50 and 25% moisture of field capacity and rootstocks factor (10 citrus genotypes provided by Citrus Breeding Program of Embrapa Cassava and Tropical Fruits. A randomized block design was adopted with three replications and 15 plants per plot. Shoot, leaves, stem, root and total dry mass, root/shoot ratio, leaf weight ratio and relative yield were evaluated. Water deficit reduced the total dry mass and increased the root

  1. Performance of 'Okitsu' Satsuma Mandarin on nine rootstocks

    Directory of Open Access Journals (Sweden)

    Zuleide Hissano Tazima

    2013-12-01

    Full Text Available Mandarins have become increasingly valued as citrus fruits for the fresh market due to the easy peeling, attractive flavor, and health and nutritional properties. Plant growth and yield, and characteristics of fruits of 'Okitsu' Satsuma mandarin (Citrus unshiu Marc. trees grafted on nine rootstocks were evaluated in Londrina, northern Paraná, Brazil. The rootstocks were: 'Rangpur' lime (Citrus limonia Osb.; 'Cleopatra' (Citrus reshni hort. ex Tanaka and 'Sunki' mandarins (Citrus sunki hort. ex Tanaka; 'C-13' [Citrus sinensis × Poncirus trifoliata (L. Raf.] and 'Carrizo' citranges [C. sinensis × P. trifoliata (L. Raf.]; 'Volkamer' lemon (Citrus volkameriana V. Ten. & Pasq.; trifoliate orange [P. trifoliata (L. Raf.; 'Caipira DAC' sweet orange [C. sinensis (L. Osb.] and 'Swingle' citrumelo [Citrus paradisi Macfad. cv. Duncan × P. trifoliata (L. Raf.]. The highest plant growth was for the trees on 'Cleopatra' mandarin and 'Caipira DAC' sweet orange. In contrast, the smallest size was for the trees on 'Volkamer' lemon and trifoliate orange. The largest difference between the trunk diameter below and above the grafting point was induced by 'Swingle' citrumelo. Trees of 'Okitsu' Satsuma mandarin on 'Swingle' citrumelo presented the highest yield, while 'C-13', 'Carrizo', 'Sunki', and 'Swingle' induced the largest fruit masses. With regard to fruit characteristics, 'Carrizo' and trifoliate orange induced the best ratio and juice content. Based on theoretical values, 'Rangpur' lime and 'Volkamer' lemon induced the lowest yields

  2. Rootstock effects fruit quality among 'Ray Ruby' grapefruit trees grown in the Indian River district of Florida

    Science.gov (United States)

    The objective of this experiment was to compare fruit quality parameters of ‘Ray Ruby’ grapefruit grown on seven rootstocks. Four recent releases from the USDA rootstock breeding program, US-852, US-897, US-942 and US-812 (all Citrus reticulata x P. trifoliata hybrids), X639 (C. reticulata x P. tri...

  3. 缺镁、铁、硼胁迫对4个柑橘砧木生长及养分吸收的影响%Effects of Magnesium, Iron, Boron Deficiency on the Growth and Nutrition Absorption of Four Major Citrus Rootstocks

    Institute of Scientific and Technical Information of China (English)

    韩佳; 周高峰; 李峤虹; 刘永忠; 彭抒昂

    2012-01-01

    通过水培方式分别研究了缺镁、铁、硼处理对枳、香橙、红橘、崇义野橘4种柑橘砧木植株和根系生长及养分吸收的影响。结果表明:缺镁处理下,红橘在株高、叶片数、叶绿素含量、总根长、总根表面积及镁吸收速率等变化中表现出较强的抗缺镁特性,崇义野橘次之,枳、香橙较差;缺铁处理下,香橙在株高、叶片数、植株干样质量、总根体积、总根表面积和铁吸收速率等变化中表现出较强的抗缺铁特性,红橘次之,枳、崇义野橘较差;缺硼处理下,红橘在总根数、总根表面积、总根体积及硼吸收速率的变化中表现出较强的抗缺硼能力,而崇义野橘的地上部较耐缺硼,香橙、枳则表现出不耐缺硼。%The effects of magnesium(Mg),iron(Fe)and boron(B)deficiency on growth and physiological characteristics in shoots and roots of four citrus rootstocks{Trifoliate orange[Poncirus trifoliate(L.)Raf.],Fragrant citrus(Citrus junos Sieb.ex Tanaka),Red tangerine(Citrus reticulate Blanco)and Congyi wild mandarin(Citrus reticulata)} were investigated by using hydroponic culture. Results indicated that the plant height,total leaves,chlorophyll content,total roots length,total roots surface and Mg specific absorption rate were better in red tangerine than those in other rootstocks under the treatment of Mg deficiency. In the treatment of Fe deficiency,the plant high,total leaves,dry weight of plant,total roots volume,total roots surface and Fe specific absorption rate were better in fragrant citrus than those in other rootstocks. In B deficiency treatment,the roots number of tips,total roots surface,total roots volume and B specific absorption rate in Red tangerine and the plant high,total leaves and dry weight of shoot in Congyi wild mandarin were better than those in other rootstocks,respectively.

  4. Deficit irrigation and rootstock: their effects on water relations, vegetative development, yield, fruit quality and mineral nutrition of Clemenules mandarin.

    Science.gov (United States)

    Romero, P; Navarro, J M; Pérez-Pérez, J; García-Sánchez, F; Gómez-Gómez, A; Porras, I; Martinez, V; Botía, P

    2006-12-01

    Differences between rootstocks, 'Cleopatra' mandarin and 'Carrizo' citrange, in soil-plant water relations and the influence of these factors on vigor, crop yield, fruit quality and mineral nutrition were evaluated in field-grown Clemenules mandarin trees irrigated at 100% of potential seasonal evaporation (ET(c)) (control treatment), or irrigated at 100% ET(c), except during Phases I and III of fruit growth and post-harvest when no irrigation was applied (deficit irrigation (DI) treatment), for 3 years. Differences between rootstocks in plant-soil water relations were the primary cause of differences among trees in vegetative development and fruit yield. After 3 years of DI treatment, trees on 'Cleopatra' showed more efficient soil water extraction than trees on 'Carrizo', and maintained a higher plant water status, a higher gas exchange rate during periods of water stress and achieved faster recovery in gas exchange following irrigation after water stress. The DI treatment reduced vegetative development more in trees on 'Carrizo' than in trees on 'Cleopatra'. Cumulative fruit yield decreased more in DI trees on 'Carrizo' (40%) than on 'Cleopatra' (27%). The yield component most affected by DI in 'Cleopatra' was the number of fruit, whereas in 'Carrizo' it depended on the severity of water stress reached in each phase (severe water stress in Phase I affected mainly the number of fruit, whereas it affected fruit size the most in Phase III). In the third year of DI treatment, water-use efficiency decreased sharply in trees on 'Carrizo' (70%) compared to trees on 'Cleopatra' (30%). Thus, trees on 'Cleopatra' were able to tolerate moderate water stress, whereas trees on 'Carrizo' were more sensitive to changes in soil water content.

  5. AN EXPLORATION OF FACTORS AFFECTING DEVELOPMENT OF CITRUS INDUSTRY IN TANZANIA: EMPIRICAL EVIDENCE FROM MUHEZA DISTRICT, TANGA REGION

    Directory of Open Access Journals (Sweden)

    Robert Makorere

    2014-04-01

    Full Text Available The paper stresses on understanding factors affecting development of citrus industry in Tanzania particularly in Muheza District, in Tanga region. Citrus fruit is one of the most important crops in Muheza District of Tanga region in Tanzania particularly in improving rural farmers’ income. The study employed institutional framework methodology. The study disclosed that the government of Tanzania has been implementing various agricultural development programmes in improving citrus fruit production as well as to enhance farmers’ income. However, yet the results reveal that the citrus farming practices in the surveyed area are not well developed. And these are because citruses are still grown under rain fed regime without any form of irrigation, citrus seedlings are produced by individual farmers locally in their backyard nurseries. There is no professional company responsible for seedling production. Also, citrus farmers’ skills in citrus husbandry practices are limited. Lastly, all citrus varieties used contain many seeds in the citrus fruits whereas the market demands seedless citrus fruits. It is therefore, recommended that the policy maker should focus on development of citrus industry in Tanzania using proper institutional framework support, which could increase growth and development of citrus production through the provision of subsides for inputs to reduce cost of production and enlightenment campaigns to improve farmer’s knowledge and technical skills on how to reach lucrative markets.

  6. Apple and pear rootstock research in Lithuania

    OpenAIRE

    Kviklys, Darius

    2006-01-01

    The paper presents ongoing apple and pear rootstock trials at the Lithuanian Institute of Horticulture. Rootstock research projects are established in following directions: rootstock and location interaction (Baltic fruit rootstock studies where Byelorussian, Estonian, Latvian, Lithuanian and Polish research institutions are involved); budding high effect on rootstock performance; interstock trials; rootstock effect on fruit quality, ripening time and fruit storage; rootstock and tree trainin...

  7. Níveis de alumínio e acúmulo de macronutrientes em porta-enxertos cítricos em cultivo hidropônico Aluminum levels and macronutrient accumulation in citrus rootstocks in hydroponic solution

    Directory of Open Access Journals (Sweden)

    Carlos Henrique dos Santos

    1999-01-01

    Full Text Available O presente trabalho teve como objetivo avaliar a influência de diferentes níveis de alumínio no acúmulo de macronutrientes pelos porta-enxertos cítricos limoeiro Cravo e citrumeleiro Swingle, sob cultivo hidropônico. Os tratamentos utilizados em condições de casa de vegetação seguiram o delineamento estatístico inteiramente casualizado, com 3 repetições, em parcelas subdivididas. Os níveis de alumínio utilizados foram: 0, 7,5, 15, 22,5 e 30 mg L-1, na forma de AlCl3.6 H2O. Determinaram-se o acúmulo de N, P, K, Ca, Mg, S e do Al da matéria seca vegetal, relacionando-os com os pesos da matéria seca da parte aérea (folhas e caule e raízes durante o período de 84 dias, com coletas de plantas a cada 14 dias. Conclui-se que, com adição a partir de 7,5 mg L-1 de alumínio em solução nutritiva ocorreram alterações fisiológicas e reduções significativas no acúmulo de macronutrientes associado à redução nos pesos da matéria seca das folhas, caule e raízes das plantas de citrumelo Swingle.The aim of this research was to study the influence of different levels of aluminum on macronutrient contents of citrus rootstocks of the `Rangpur' lime and the `Swingle' citrumelo, in hydroponic solution. The treatments, established under greenhouse conditions, followed a completely randomized experimental design, with 3 replications, distributed in split-plots. The levels of aluminum were: 0; 7.5; 15; 22.5 and 30 mg L-1, applied as AlCl3.6 H2O. The evaluated chemical plant parameters were the concentrations of N, P, K, Ca, Mg, S, Al and dry weight of leaves, stem and root system. The results showed that with adition of 7.5 mg L-1 of Al to the nutrient solution there was a significant decrese of nutrient contents and a decrese in leave, stem and root system dry weight of `Swingle' citrumelo.

  8. Diagnóstico do estado nutricional de N em porta-enxertos de citros, utilizando-se de teores foliares de clorofila Diagnostic of nitrogen nutritional level in citrus rootstocks using foliar chlorophyll content

    Directory of Open Access Journals (Sweden)

    ANTÔNIO DECARLOS NETO

    2002-04-01

    roots dry matter mass, foliar area and NO3-N content for aerial portion, indicating that the total chlorophyll content can be used as indicator to diagnose N in citrus rootstocks cultivated in tubes. The maximum chlorophylls content estimated in rootstocks 'Tangelo-Orlando', 'Cravo', 'Volkameriano', 'Cleópatra' e 'Sunki' occurred in doses 1,461; 2,386; 2,494; 1,444; and 2,284 (mg N/dm³ of substrate, respectively. Total foliar chlorophyll content adequate for rootstocts of 'Tangelo Orlando' showed to be placed between 1.80 to 3.00 mg of total chlorophyll/dm² of leaf at 120 days after sowing, for lemon 'Cravo' between 2.46 to 3.94 while the 'Volkameriano' showed to be placed between 2.27 to 4.23 mg of total chlorophyll/dm² of leaf. Adequate values for foliar contents for total chlorophyll for Cleopatra tangerine showed to be 3.29 to 4.00 mg of total chlorophyll/dm² of leaf while for 'Sunki' tangerine the values showed to be 1.80 to 3.16 mg of total chlorophyll/dm² of leaf.

  9. Control of virus diseases of citrus.

    Science.gov (United States)

    Lee, Richard F

    2015-01-01

    Citrus is thought to have originated in Southeast Asia and horticulturally desirable clonal selections have been clonally cultivated for hundreds of years. While some citrus species have nucellar embryony, most cultivation of citrus has been by clonal propagation to ensure that propagated plants have the same traits as the parent selection. Clonal propagation also avoids juvenility, and the propagated plants produce fruit sooner. Because of the clonal propagation of citrus, citrus has accumulated a large number of viruses; many of these viruses are asymptomatic until a susceptible rootstock and/or scion is encountered. The viruses reported to occur in citrus will be summarized in this review. Methods of therapy to clean selected clones from viruses will be reviewed; the use of quarantine, clean stock, and certification programs for control of citrus viruses and other strategies to control insect spread citrus viruses, such as mild strain cross-protection and the use of pest management areas will be discussed.

  10. Sweet orange trees grafted on selected rootstocks fertilized with nitrogen, phosphorus and potassium

    Directory of Open Access Journals (Sweden)

    Quaggio José Antônio

    2004-01-01

    Full Text Available The majority of citrus trees in Brazil are grafted on 'Rangpur lime' (Citrus limonia Osb. rootstock. Despite its good horticultural performance, search for disease tolerant rootstock varieties to improve yield and longevity of citrus groves has increased. The objective of this work was to evaluate yield efficiency of sweet oranges on different rootstocks fertilized with N, P, and potassium. Tree growth was affected by rootstock varieties; trees on 'Swingle' citrumelo [Poncirus trifoliata (L. Raf. × C. paradisi Macf.] presented the smallest canopy (13.3 m³ in the fifth year after tree planting compared to those on 'Rangpur lime' and 'Cleopatra' mandarin [C. reshni (Hayata hort. ex Tanaka] grown on the same grove. Although it was observed an overall positive relationship between canopy volume and fruit yield (R² = 0.95**, yield efficiency (kg m-3 was affected by rootstocks, which demonstrated 'Rangpur lime' superiority in relation to Cleopatra. Growth of citrus trees younger than 5-yr-old might be improved by K fertilization rates greater than currently recommended in Brazil, in soils with low K and subjected to nutrient leaching losses.

  11. Effects of Different Rootstocks on Key Photosynthetic Enzyme in Leaves and Fruit Quality of Citrus cv.‘Huangguogan’%不同砧木对‘黄果柑’叶片光合作用关键酶和果实品质的影响

    Institute of Scientific and Technical Information of China (English)

    廖玲; 汪志辉; 曾海琼; 曹淑燕; 古咸杰; 李清南; 高婧斐; 张婷婷; 石冬冬; 熊博

    2015-01-01

    This study investigated the variation patterns in the leaf net photosynthetic rate (Pn), leaf concentra-tions of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and Rubisco activase (RCA), and quality dynamics of fruits in Citrus cv.‘Huangguogan’ trees grafted using Poncirus trifoliate, Citrus reticulata and C. junos rootstocks. The results showed that diurnal variations of leaf Pn in ‘Huangguogan’ exhibited bimodal curves. Peak Pn values were obtained at different times with different magnitudes in the three types of grafted trees. Trees grafted on C. junos and P. trifoliate rootstocks showed higher leaf Pn values. Leaf concentrations of the two photosynthetic enzymes in grafted trees were signiifcantly higher than those in the control trees. Com-pared with control trees, in grafted trees, the peak values of total soluble solids (TSS) were postponed to differ-ent degrees, thereby prolonging the preservation time of the fruits of the trees. Therefore, out of the three root-stocks, C. junos has the most profound effect on the fruit quality of‘Huangguogan’.%本文研究了以枳壳、红橘、香橙为砧木的‘黄果柑’嫁接树叶片净光合速率(Pn)、核酮糖-1,5-二磷酸羧化酶/加氧酶(Rubisco)和活化酶(RCA)浓度及果实动态品质的变化规律。结果表明:‘黄果柑’ Pn日变化呈双峰曲线,3种嫁接树峰值的出现时间及大小不同,以香橙和枳壳为砧木的‘黄果柑’叶片Pn较高;嫁接树叶片中2种酶浓度均显著高于对照;与对照相比,3种嫁接树的总可溶性固形物(TSS)峰值出现时间有不同程度推迟,果实留树保鲜时间延长。由此可见,3种砧木中香橙对‘黄果柑’果实品质的影响最大。

  12. Transmission Rates of ‘Ca. Liberibacter asiaticus’ by Asian Citrus Psyllid Are Enhanced by the Presence and Developmental Stage of Citrus Flush.

    Science.gov (United States)

    Hall, David G; Albrecht, Ute; Bowman, Kim D

    2016-04-01

    Asian citrus psyllid (Diaphorina citri Kuwayama) transmits a bacterium ‘Candidatus Liberibacter asiaticus’ (CLas) putatively responsible for a devastating citrus disease known as Asiatic huanglongbing (HLB) (citrus greening disease). The psyllid and disease have invaded many citrus-growing regions including the United States, where the disease is seriously jeopardizing the Florida citrus industry. We recently concluded research that showed CLas transmission rates are increased when citrus flush is present. Flush is any new leaf growth ranging in development from first emergence up until the leaves are fully expanded yet still tender. In an experiment with seedlings of a rootstock cultivar ‘US-942’, a 1-wk infestation of 20 Asian citrus psyllids from an infected colony resulted in 53–60% of seedlings becoming infected when flush was present compared with only 7% when no flush was present. In a second experiment with ‘US-942’, 77–97% of seedlings became infected when flush was present compared with 40% when no flush was present. A similar experiment with ‘Valencia’ sweet orange resulted in 23, 80, and 3% seedlings becoming infected when young, older, or no flush was present, respectively. Young plants are therefore more likely to contract HLB if flush is present, with older flush promoting higher infection rates under the conditions of this study. Based on this finding, healthy citrus should be protected from Asian citrus psyllid infestations throughout a flush. To evaluate germplasm for CLas resistance, inoculations using infected Asian citrus psyllid would best be achieved if flush is present.

  13. Efeito de sistemas de produção e doses de adubo de liberação lenta no estado nutricional de porta-enxerto cítrico The effect of production systems and doses of controlled-release fertilizer on the nutritional status of citrus rootstock

    Directory of Open Access Journals (Sweden)

    Luiz Augusto Lopes Serrano

    2004-12-01

    Full Text Available O sistema de produção do porta-enxerto, antes da repicagem, pode modificar o sistema radicular das plântulas e a resposta destas à adubação. Assim, o objetivo desse trabalho foi avaliar os efeitos de três sistemas de produção do limoeiro 'Cravo' e de cinco doses de um adubo de liberação lenta, aplicados após a repicagem, sobre o estado nutricional do limoeiro 'Cravo' no ponto de enxertia. O experimento foi conduzido, sob viveiro telado, em esquema fatorial 3 x 5, com sete repetições e uma planta por parcela. Os sistemas de produção do porta-enxerto foram: 1- produção em tubetes e citrovasos preenchidos com substrato comercial composto por casca de pínus; 2- produção em tubetes e citrovasos preenchidos com substrato composto por bagaço de cana-de-açúcar + torta de filtro (3:2; v:v, e 3- produção em blocos prensados e citrovasos constituídos pela prensagem do substrato utilizado no sistema 2. As doses de adubo de liberação lenta, fórmula NPK 14-14-14, foram: 5; 10; 15; 20 e 25 g/planta. O sistema de produção do porta-enxerto, antes da repicagem, influenciou na resposta do limoeiro 'Cravo' à adubação após a repicagem. No ponto de enxertia, as plantas cultivadas no sistema de blocos prensados apresentaram menores teores foliares de P, K e Fe em relação às plantas provenientes de tubetes, mas apresentaram maiores médias de crescimento (peso seco do sistema radicular, peso seco de folhas, peso seco de caules e diâmetro do caule. Plantas cultivadas no sistema 1 apresentaram sintomas foliares de deficiência de Fe, enquanto as plantas dos outros dois sistemas apresentaram sintomas foliares de deficiência de Mg.The production system of citrus rootstock before the transplanting can modify the seedlings root system and the response of these to fertilization. The objective of this experiment was to evaluate the effects of three production systems of 'Rangpur' lime tree and five doses of a controlled

  14. Root distribution of rootstocks for 'Tahiti' lime

    Directory of Open Access Journals (Sweden)

    Neves Carmen Silvia Vieira Janeiro

    2004-01-01

    Full Text Available Field studies on citrus roots are important for genetic selection of cultivars and for management practices such as localized irrigation and fertilization. To characterize root systems of six rootstocks, taking into consideration chemical and physical characteristics of a clayey Typic Hapludox of the Northern State of Paraná, this study was performed having as scion the 'IAC-5 Tahiti' lime [Citrus latifolia (Yu. Tanaka]. The rootstocks 'Rangpur' lime (C. limonia Osbeck, 'Africa Rough' lemon (C. jambhiri Lush., 'Sunki' mandarin [C. sunki (Hayata hort. ex Tan.], Poncirus trifoliata (L. Raf., 'C13' citrange [C. sinensis (L. Osb. x P. trifoliata (L. Raf] and 'Catânia 2' Volkamer lemon (C. volkameriana Ten. & Pasq. were used applying the trench profile method and the SIARCS® 3.0 software to determine root distribution. 'C-13' citrange had the largest root system. 'Volkamer' lemon and 'Africa Rough' lemon presented the smallest amount of roots. The effective depth for 80 % of roots was 31-53 cm in rows and 67-68 cm in inter-rows. The effective distance of 80 % of roots measured from the tree trunk exceeded the tree canopy for P. trifoliata, 'Sunki' mandarin, and 'Volkamer' and 'Africa Rough' lemons.

  15. Development and reproduction of Panonychus citri (Prostigmata: Tetranychidae) on different species and varieties of citrus plants.

    Science.gov (United States)

    Zanardi, Odimar Zanuzo; Bordini, Gabriela Pavan; Franco, Aline Aparecida; de Morais, Matheus Rovere; Yamamoto, Pedro Takao

    2015-12-01

    The species and varieties of citrus plants that are currently grown can favor the population growth of the citrus red mite Panonychus citri (McGregor) (Prostigmata: Tetranychidae) and alter the pest management programs in citrus groves. In this study we evaluated, in the laboratory, the development and reproduction of P. citri and estimated its life table parameters when reared on four varieties of Citrus sinensis (L.) Osbeck (Valencia, Pera, Natal, and Hamlin), one variety of Citrus reticulata Blanco (Ponkan) and one variety of Citrus limon (L.) Burm. (Sicilian). The incubation period and egg viability were not affected by the host plant. However, the development and survival of the immature stage were significantly lower on Hamlin orange than on Valencia, Pera and Natal oranges, Ponkan mandarin and Sicilian lemon. The fecundity and oviposition period of females were lower on Hamlin orange than on the other hosts. Mites reared on Valencia orange and Sicilian lemon had a higher net reproductive rate (R 0 ), intrinsic growth rate (r) and finite rate of increase (λ), and a shorter interval between generations (T) than on Pera, Natal and Hamlin oranges and Ponkan mandarin. On the other hand, mites reared on Hamlin orange had the lowest R 0 , r and λ and the highest T among the hosts. Based on the results obtained we recommend that for Valencia orange and Sicilian lemon, the mite monitoring programs should be more intense to detect the initial infestation of pest, avoiding the damage in plants and the increase in production costs.

  16. Expression of Bacillus thuringiensis cytolytic toxin (Cyt2Ca1) in citrus roots to control Diaprepes abbreviatus larvae

    Science.gov (United States)

    Diaprepes abbreviatus (L.) is an important pest of citrus in the USA. Currently, no effective management strategies of Diaprepes abbreviatus exist in citriculture. To protect citrus against Diaprepes abbreviatus a transgenic citrus rootstock expressing Bacillus thuringiensis Cyt2Ca1, an insect toxin...

  17. Elucidating the molecular responses of apple rootstock resistant to ARD pathogens: challenges and opportunities for development of genomics-assisted breeding tools.

    Science.gov (United States)

    Zhu, Yanmin; Fazio, Gennaro; Mazzola, Mark

    2014-01-01

    may lead to different outcomes between rootstocks in response to invasion by necrotrophic pathogens. Elucidation of host defense mechanisms is critical in developing molecular tools for genomics-assisted breeding of resistant apple rootstocks. Due to their perennial nature, use of resistant rootstocks as a component for disease management might offer a durable and cost-effective benefit to tree performance than the standard practice of soil fumigation for control of ARD.

  18. Regional Division of Production and Development Strategy of Citrus in Hunan Province

    Institute of Scientific and Technical Information of China (English)

    Yu YANG; Wen DENG; Jianquan LI; Weihong WANG; Guolin HUANG; Ping ZHANG

    2012-01-01

    [Objective] The aim was to research regional division of citrus production and development strategies in Hunan Province. [Method] According to Rural Statisti- cal Yearbook in Hunan Province during 2002-2011, Citrus in Hunan province were divided into three production regions, namely, superior region, sub-superior and non- superior region. On the base of the divisions, the ecological regionalization and brand strategy, Optimization of regional distribution and developing strategy were proposed, with consideration of avoiding frozen zones, in this paper. [Result] Fresh and processing bases of mandarin orange (C.unshiu Marc), and specialty industries of seedless ponkan(C.reticulata Blanco), Bingtang orange (C.sinensis Osbeck Bing- tangcheng), Dayongjuhuaxinyou (Cgrandis (L.) Osbeck Dayongjuhuaxinyou) and An- jiangxiangyou (C.grandis (L.) Osbeck Anjiangxiangyou) should be constructed, where fresh fruit is dominant, supplemented by canned fruit and juice. Industry belt of sat- suma orange, fresh or processing food, is mainly built, for proportion of early and earlier ripe satsuma orange is over 50% of total yield in Xiangzhong citrus zone; in- dustry belt of excellent fresh navel orange and processing sweet orange should be highlighted in Xiangnan. [Conclusion] The research provides references for decision- making for governments, especially on optimization of citrus production regions and development of citrus industry.

  19. A label-free differential quantitative mass spectrometry method for the characterization and identification of protein changes during citrus fruit development

    OpenAIRE

    Lin Dawei; Fass Joseph N; Phinney Brett S; Eigenheer Richard A; Fon Mario; Katz Ehud; Sadka Avi; Blumwald Eduardo

    2010-01-01

    Abstract Background Citrus is one of the most important and widely grown commodity fruit crops. In this study a label-free LC-MS/MS based shot-gun proteomics approach was taken to explore three main stages of citrus fruit development. These approaches were used to identify and evaluate changes occurring in juice sac cells in various metabolic pathways affecting citrus fruit development and quality. Results Protein changes in citrus juice sac cells were identified and quantified using label-fr...

  20. Comparación del "Tabog" (Swinglea glutinosa Merr con el limón "rugoso" (Citrus jambhiri Swingle y la mandarina "Cleopatra" (C. reticulata Swingle como porta-injerto para la lima acida ''Tahiti" (C. aurantifolia Swingle

    Directory of Open Access Journals (Sweden)

    Restrepo C. Orlando

    1987-09-01

    Full Text Available At the C.N.I.-I.C.A. Palmira, fruit trees program the influence of "Tabog" Swinglea glutinosa was evaluated as rootstock for acid lime "Tahiti" Citrus aurantifolia, taking into account the following aspects: development and productivility of the trees quality and growth of fruits, demands of nutriments, and resistance or susceptibility to pest and disease; comparing its behavior with the commercial rootstocks rough, lemon C. jambhiri and mandarina, "Cleopatra" C. reticulata.En el C.N.l. Palmira del Instituto Colombiano Agropecuario (lCA, se evaluó la influencia del "Tabog" Swinglea glutinosa como porta-injerto para la lima "Tahiti " Citrus aurantifolia, teniendo en cuenta los siguientes aspectos: desarrollo y productividad del árbol, calidad y desarrollo de los frutos, exigencias de nutrimentos, resistencia o susceptibilidad a plagas y enfermedades; comparando su comportamiento con los porta-injertos comerciales limón "Rugoso" C. jambhiri y la mandarina "Cleopatra " C. reticulata.

  1. Micropropagation of peach rootstocks and cultivars.

    Science.gov (United States)

    Balla, Ildikó; Mansvelt, Lucienne

    2013-01-01

    Peach (Prunus persica (L.) Batsch) is one of the most popular stone fruits, commercially produced largely in Mediterranean and, to a lesser extent, in continental climatic conditions. Several breeding programs with different aims release annually large numbers of new cultivars. Micropropagation offers a suitable method to provide the growers of sufficient quantities of rootstocks, as well as of pathogen-free planting material of old and new cultivars.An effective four-step micropropagation procedure for cultivar and rootstock production is described here, based on the use of modified MS and WPM media. The health status of the initial shoot tips is very important, also because the growth and proliferation rate of shoot cultures from virus-infected clones are generally very poor. Proliferation and elongation phases depend on the major macro-elements, as well as the content and ratio of plant growth regulators. It is important to grow the cultures at 22°C, as hyperhydricity may develop at higher temperatures. Although sucrose is the most common carbon source used during proliferation and rooting, for some peach cultivars and rootstocks the replacement of sucrose (10 g/L) with glucose (20 g/L) in the rooting medium improves the rooting and survival rates of plants in the acclimatization phase. The rooting rate of the rootstock "Cadaman" is improved with the chelated form of iron FeEDDHA at 150 mg/L. Rooted plants are acclimatized in greenhouse under high humidity conditions.

  2. Analysis of 13000 unique Citrus clusters associated with fruit quality, production and salinity tolerance

    Directory of Open Access Journals (Sweden)

    Dossat Carole

    2007-01-01

    important metabolic pathways known to affect fruit quality were represented in the unigene set. Overall, the similarity analyses indicated that the sequences of the genes belonging to these varieties and rootstocks were essentially identical, suggesting that the differential behaviour of these species cannot be attributed to major sequence divergences. This Citrus EST assembly contributes both crucial information to discover genes of agronomical interest and tools for genetic and genomic analyses, such as the development of new markers and microarrays.

  3. Transferability of the EST-SSRs developed on Nules clementine (Citrus clementina Hort ex Tan to other Citrus species and their effectiveness for genetic mapping

    Directory of Open Access Journals (Sweden)

    Ollitrault Patrick

    2008-06-01

    Full Text Available Abstract Background During the last decade, numerous microsatellite markers were developed for genotyping and to identify closely related plant genotypes. In citrus, previously developed microsatellite markers were arisen from genomic libraries and more often located in non coding DNA sequences. To optimize the use of these EST-SSRs as genetic markers in genome mapping programs and citrus systematic analysis, we have investigated their polymorphism related to the type (di or trinucleotide or their position in the coding sequences. Results Among 11000 unigenes from a Clementine EST library, we have found at least one microsatellite sequence (repeated units size ranged from 2 to 6 nucleotides in 1500 unigenes (13.6%. More than 95% of these SSRs were di or trinucleotides. If trinucleotide microsatellites were encountered trough all part of EST sequences, dinucleotide microsatellites were preferentially (50% concentrated in the 5' 100th nucleotides. We assessed the polymorphism of 41 EST-SSR, by PCR amplification droved with flanking primers among ten Citrus species plus 3 from other genera. More than 90% of EST-SSR markers were polymorphic. Furthermore, dinucleotide microsatellite markers were more polymorphic than trinucleotide ones, probably related to their distribution that was more often located in the 5' UnTranslated Region (UTR. We obtained a good agreement of diversity relationships between the citrus species and relatives assessed with EST-SSR markers with the established taxonomy and phylogeny. To end, the heterozygosity of each genotype and all dual combinations were studied to evaluate the percentage of mappable markers. Higher values (> 45% were observed for putative Citrus inter-specific hybrids (lime lemon, or sour orange than for Citrus basic true species (mandarin, pummelo and citron (70% with a significant proportion suitable for synteny analysis. Conclusion Fourty one new EST-SSR markers were produced and were available for

  4. HLB/ACP Resistance or Tolerance in Non-transgenic Citrus Scion Varieties: Potential Commercial Significance

    Science.gov (United States)

    Poncirus trifoliata hybrids grown in the USHRL variety block on Sun Chu Sha (a unifoliate mandarin rootstock similar to Cleopatra) were tested for CLas 16S rDNA and Citrus dehydrin (as an internal standard to permit expression of data in CLas genomes/citrus genomes) by qPCR, assessing random quadran...

  5. Effects of Different Rootstocks on the Contents of Nutrient in Leaves of Yunning No.1 Citrus×Limon%不同砧木对云柠1号柠檬叶片养分含量的影响

    Institute of Scientific and Technical Information of China (English)

    胡敏; 兰翔; 何玉广; 郑苍松; 李进学; 胡承孝; 谭启玲

    2014-01-01

    以云柠1号柠檬(Citrus ×limon‘ Yunning No.1’)为研究对象,在相同管理条件下研究红橘(Citrusreticulata Blanco)、酸柚(Citrus grandis Osbeck)、香橙(Citrus junos Lsieb)、富民枳(Poncirus polyandra S.)、小香橼(Citrus medica V.)、枳橙(Poncirus trifoliata L.Raf.×Citrus.sinensisL.Osb.)、枳类(Poncirus trifoliata)7种砧木对云柠1号柠檬叶片养分含量的影响.试验结果表明,不同砧木接穗组合对云柠1号柠檬叶片养分含量影响显著.大量元素中,以小香橼为砧木处理的云柠1号柠檬叶片N含量最高,比7种处理的平均含量高出0.80个百分点:以富民枳为砧木处理的云柠1号柠檬叶片K含量为0.91%,为7种处理中含量最高.微量元素中,以红橘和香橙为砧木处理的云柠1号柠檬叶片Ca和Mg含量最高;以富民枳和小香橼为砧木处理的的云柠1号柠檬叶片Fe、Mn含量最高,各处理间差异显著.结合叶片养分诊断指标适宜范围,综合评价得出以富民枳为砧木处理的叶片中矿质元素养分含量最佳,当地适宜推广富民枳为云柠1号柠檬砧木以达到养分的高效吸收利用.

  6. Citrus Waste Biomass Program

    Energy Technology Data Exchange (ETDEWEB)

    Karel Grohman; Scott Stevenson

    2007-01-30

    Renewable Spirits is developing an innovative pilot plant bio-refinery to establish the commercial viability of ehtanol production utilizing a processing waste from citrus juice production. A novel process based on enzymatic hydrolysis of citrus processing waste and fermentation of resulting sugars to ethanol by yeasts was successfully developed in collaboration with a CRADA partner, USDA/ARS Citrus and Subtropical Products Laboratory. The process was also successfully scaled up from laboratory scale to 10,000 gal fermentor level.

  7. Micropropagation of Citrus spp. by organogenesis and somatic embryogenesis.

    Science.gov (United States)

    Chiancone, Benedetta; Germanà, Maria Antonietta

    2013-01-01

    Citrus spp., the largest fruit crops produced worldwide, are usually asexually propagated by cuttings or grafting onto seedling rootstocks. Most of Citrus genotypes are characterized by polyembryony due to the occurrence of adventive nucellar embryos, which lead to the production of true-to-type plants by seed germination. Tissue culture and micropropagation, in particular, are valuable alternatives to traditional propagation to obtain a high number of uniform and healthy plants in a short time and in a small space. Moreover, in vitro propagation provides a rapid system to multiply the progeny obtained by breeding programs, allows the use of monoembryonic and seedless genotypes as rootstocks, and it is very useful also for breeding and germplasm preservation.In this chapter, two protocols regarding organogenesis of a rootstock and somatic embryogenesis of a cultivar have been described.

  8. Implementation of molecular marker technologies in the apple rootstock breeding program in Geneva - challenges and successes

    Science.gov (United States)

    The Geneva® Apple Rootstock Breeding program was initiated in the early 1970’s with the overarching goal of developing disease resistant, productive and precocious apple rootstocks. Near the turn of the century the program was joined with USDA ARS resources and in addition to focusing on releasing ...

  9. Crescimento e desenvolvimento de pessegueiros ‘Chimarrita’ e ‘Maciel’ sobre diferentes porta-enxertos e locais de cultivo Growth and development of ‘Chimarrita’ and ‘Maciel’ peach trees on different rootstocks and cultivating areas

    Directory of Open Access Journals (Sweden)

    Simone Padilha Galarça

    2013-02-01

    Full Text Available Objetivou-se com o presente trabalho avaliar a influência dos porta-enxertos no que se refere ao crescimento vegetativo e desenvolvimento dos pessegueiro 'Chimarrita' e 'Maciel' em três locais de cultivo. O experimento foi desenvolvido em três locais de cultivo: 1 (Embrapa Uva e Vinho, 2 (EEA UFRGS e 3 (CAP UFPel, em três anos. As cultivares de pessegueiro utilizadas foram: 'Chimarrita' e 'Maciel' enxertadas sobre seis porta-enxertos ('Aldrighi', 'Capdeboscq', 'Flordaguard', 'Nemaguard', 'Okinawa' e Umezeiro, no espaçamento 1,5 X 5,0m e conduzidas no sistema em "V". Foram avaliados: volume de copa, diâmetro de tronco, massa fresca da poda, produção por planta acumulada, comprimento, espessura, gemas floríferas e densidade florífera do ramo produtivo. Também foi avaliado de forma visual o ponto de enxertia. O porta-enxerto Umezeiro induziu menor vigor nos três locais de cultivo estudados e na média dos três anos. Ele pode ser indicado para utilização sob 'Maciel' nas condições edafoclimáticas do local 3. No local 1 o porta-enxerto, 'Nemaguard' possui alto vigor e maior produção acumulada, sendo o mais indicado. Já para o local 2, os porta-enxertos 'Capdeboscq', 'Okinawa' e 'Flordaguard' são os mais indicados. Os porta-enxertos afetam as características de crescimento e desenvolvimento das cultivares 'Chimarrita' e 'Maciel', o vigor destas é menor sobre o porta-enxerto Umezeiro nos três locais de cultivo. Todos os porta-enxertos podem ser indicados para os três locais de cultivo, com exceção do Umezeiro, que somente pode ser indicado em combinação com a cultivar 'Maciel' no local 3.The objective of this study was to evaluate the influence of rootstocks in relation to vegetative growth and development of 'Chimarrita' and 'Maciel' peach trees in three places of cultivation. The experiment was conducted in three cultivating areas: first (Embrapa Grape and Wine, second (EEA UFRGS and third (CAP UFPel, in three years

  10. Efeito da tristeza em caracteres vegetativos, produtivos e industriais da laranjeira 'Valência' enxertada em híbridos segregando para tolerância Effect of the citrus tristeza disease on vegetative, productive and industrial characters of 'Valencia' sweet orange grafted onto hybrid rootstocks segregating for tolerance

    Directory of Open Access Journals (Sweden)

    Rita Bordignon

    2003-01-01

    ólidos solúveis aumentou significativamente, 14% em média, nos híbridos intolerantes.The effect of the citrus tristeza disease caused by CTV on vegetative, productive, and industrial characters of the sweet orange 'Valencia' grafted onto seven hybrid progenies of full sibs segregating for tolerance was studied. The hybrids were originated from controlled crosses between the commercial rootstocks 'Davis A' Poncirus trifoliata (T, Sunki mandarin (S, 'São Paulo' sour orange (A and 'Limeira' Rangpur lime (C. Two sets of hybrids were studied. The first was formed by 298 individuals, from which 20 were T x S, 67 S x T, 98 S x A, 48 C x A, and 65 T x A. The second set had 1.243 hybrids, being 845 S x A, 240 A x S, 139 C x A, and 19 A x C. In the nursery, tristeza disease was responsible for 21% of death among the intolerant individuals, while among survivors transplanted to the field, an additional 13% died in a four-years period. Among the intolerant survivors in the field, tristeza reduced in four years rootstock diameter to 41%, scion diameter in 45%, and general vigor in 42%. Fruit weight was reduced in 22% in average. Yield was the most drastically affected character, being reduced to 41% in the first harvest, and up to 90% in the fifth harvest. Accumulated yields of five years were reduced 85% in the intolerant segregants among the different groups of hybrids. Productivity (yield/area of canopy was also intensely affected (46% indicating that the reduction in yield was proportionally more intense than the correspondent reduction in the vegetative growth. The relation between scion/rootstock diameters decreased 7% in the intolerant plants. Although small, it indicated that the vegetative growth of the tolerant canopies was more affected than the rootstocks, despite their intolerance. Little or no effect was detected on external peel color, juice outturn, and soluble solids/acids ratio. Acidity and soluble solids significantly increased at an average of 12 and 14

  11. A label-free differential quantitative mass spectrometry method for the characterization and identification of protein changes during citrus fruit development

    Directory of Open Access Journals (Sweden)

    Lin Dawei

    2010-12-01

    Full Text Available Abstract Background Citrus is one of the most important and widely grown commodity fruit crops. In this study a label-free LC-MS/MS based shot-gun proteomics approach was taken to explore three main stages of citrus fruit development. These approaches were used to identify and evaluate changes occurring in juice sac cells in various metabolic pathways affecting citrus fruit development and quality. Results Protein changes in citrus juice sac cells were identified and quantified using label-free shotgun methodologies. Two alternative methods, differential mass-spectrometry (dMS and spectral counting (SC were used to analyze protein changes occurring during earlier and late stages of fruit development. Both methods were compared in order to develop a proteomics workflow that could be used in a non-model plant lacking a sequenced genome. In order to resolve the bioinformatics limitations of EST databases from species that lack a full sequenced genome, we established iCitrus. iCitrus is a comprehensive sequence database created by merging three major sources of sequences (HarvEST:citrus, NCBI/citrus/unigenes, NCBI/citrus/proteins and improving the annotation of existing unigenes. iCitrus provided a useful bioinformatics tool for the high-throughput identification of citrus proteins. We have identified approximately 1500 citrus proteins expressed in fruit juice sac cells and quantified the changes of their expression during fruit development. Our results showed that both dMS and SC provided significant information on protein changes, with dMS providing a higher accuracy. Conclusion Our data supports the notion of the complementary use of dMS and SC for label-free comparative proteomics, broadening the identification spectrum and strengthening the identification of trends in protein expression changes during the particular processes being compared.

  12. Contributions of roots and rootstocks to sustainable, intensified crop production.

    Science.gov (United States)

    Gregory, Peter J; Atkinson, Christopher J; Bengough, A Glyn; Else, Mark A; Fernández-Fernández, Felicidad; Harrison, Richard J; Schmidt, Sonja

    2013-03-01

    Sustainable intensification is seen as the main route for meeting the world's increasing demands for food and fibre. As demands mount for greater efficiency in the use of resources to achieve this goal, so the focus on roots and rootstocks and their role in acquiring water and nutrients, and overcoming pests and pathogens, is increasing. The purpose of this review is to explore some of the ways in which understanding root systems and their interactions with soils could contribute to the development of more sustainable systems of intensive production. Physical interactions with soil particles limit root growth if soils are dense, but root-soil contact is essential for optimal growth and uptake of water and nutrients. X-ray microtomography demonstrated that maize roots elongated more rapidly with increasing root-soil contact, as long as mechanical impedance was not limiting root elongation, while lupin was less sensitive to changes in root-soil contact. In addition to selecting for root architecture and rhizosphere properties, the growth of many plants in cultivated systems is profoundly affected by selection of an appropriate rootstock. Several mechanisms for scion control by rootstocks have been suggested, but the causal signals are still uncertain and may differ between crop species. Linkage map locations for quantitative trait loci for disease resistance and other traits of interest in rootstock breeding are becoming available. Designing root systems and rootstocks for specific environments is becoming a feasible target.

  13. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    Science.gov (United States)

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  14. Análisis de la distribución de raíces de 12 patrones injertados con naranja "frost valencia" Citrus sinensis L. oesbeck de 14 años de edad, en condiciones climáticas de Palmira, Valle del Cauca Analysis of root distribution in 12 citrus rootstocks grown in Palmira, the Cauca Valley

    Directory of Open Access Journals (Sweden)

    Escobar T. William

    1992-12-01

    Full Text Available

    En el Centro Nacional de Investigaciones del ICA, Palmira, se estudió el sistema de raíces de 12 patrones injertados con naranja Frost Valencia, de 14 años de edad, sembrados en un suelo Franco-Arcilloso. Se tomaron muestras a 1.0, 1,5, 2.0 y 3.0 m de distancia de la base del árbol y a profundidades de 0-20, 20-40, 40-60, 60-80 Y 80-100 cm, considerando cada distancia. Los patrones que mostraron la mayor densidad de raíces fueron: Amblycarpa, Citrange Carrizo y Mandarina Cleopatra. Se encontró correlación directa y altamente significativa entre el sistema de raíces menores de 2 mm de diámetro con la altura y diámetro del árbol, lo mismo que con el volumen de la copa. Estos aspectos son de especial importancia para evaluar el grado de adaptación a diferentes condiciones de suelo, al momento de plantar un huerto.

    At the ICA National Research Center in Palmira a study of the root system of 12 rootstocks grafted with "Frost Valencia" orange 14 years old grown on clay-loam soil was conducted. Root samples were taken at distances of 1.0, 1.5, 2.0 and 3.0 m from stem and a depth of 0-20, 20-40, 40-60, 60-80 and 80-100 cm in each distances. The rootstocks Amblycarpa, Citrange Carrizo and Cleopatra Mandarin presented the greater root densities. The height, diameter and the foliage tree volume showed positive correlation whit a diameter lesser than two millimeter. That's special importance for the adaptation several soil's conditions.

  15. Development of rapid, sensitive and non-radioactive tissue-blot diagnostic method for the detection of citrus greening.

    Science.gov (United States)

    Nageswara-Rao, Madhugiri; Miyata, Shin-Ichi; Ghosh, Dilip; Irey, Mike; Garnsey, Stephen M; Gowda, Siddarame

    2013-01-01

    Citrus huanglongbing (HLB or citrus greening) is one of the most devastating diseases of citrus worldwide. The disease is caused by Gram-negative, phloem-limited α-proteobacterium, 'Candidatus Liberibacter asiaticus', vectored by the psyllid, Diaphorina citri Kuwayama. Citrus plants infected by the HLB bacterium may not show visible symptoms sometimes for years following infection and non-uniform distribution within the tree makes the detection of the pathogen very difficult. Efficient management of HLB disease requires rapid and sensitive detection early in the infection followed by eradication of the source of pathogen and the vector. The polymerase chain reaction (PCR) based method is most commonly employed for screening the infected/suspected HLB plants and psyllids. This is time consuming, cumbersome and not practical for screening large number of samples in the field. To overcome this, we developed a simple, sensitive, non-radioactive, tissue-blot diagnostic method for early detection and screening of HLB disease. Digoxigenin labeled molecular probes specific to 'Ca. L. asiaticus' nucleotide sequences have been developed and used for the detection of the pathogen of the HLB disease. The copy number of the target genes was also assessed using real-time PCR experiments and the optimized real-time PCR protocol allowed positive 'Ca. L. asiaticus' detection in citrus samples infected with 'Ca. L. asiaticus' bacterium.

  16. Avaliação genética de seleções e híbridos de limões cravo, volkameriano e rugoso como porta-enxertos para laranjeiras Valência na presença da morte súbita dos citros Genetic evaluation of selections and hybrids of rangpur lime, volkamer and rough lemons rootstocks for Valência orange trees in the presence of the citrus sudden death

    Directory of Open Access Journals (Sweden)

    Jorgino Pompeu Junior

    2013-03-01

    genótipos Rangpur- Lime x Trifoliata 3810 (1648, Rangpur- Lime x Trifoliata 5320 (1644, Limão- Cravo x Citrange- Carrizo (1524, Citrus pennivesiculata (880, Limão- Cravo x Trifoliata- Swingle A (1707, Rangpur- Rose- Lemon 124684 (864, Rangpur- Red -Lime D33.47 (867 e Limão- Cravo -Ipanema (1522. Dentre os 10 melhores genótipos para produção de frutos e para eficiência produtiva, apenas três são coincidentes: Rangpur- Rose -Lime (868, Citrus pennivesiculata (880 e Limão- Cravo-Ipanema (1522.This study aimed to perform the genetic evaluation of fruit production, productive efficiency and growth of Valência orange (Citrus sinensis trees scions grafted on selections and hybrids of Rangpur lime (C. limonia, Volkamer (C. volkameriana and Rough (C. jambhiri lemons rootstocks grown in the presence of the Citrus Sudden Death (CSD. In an affected endemic area for CSD 36 genotypes of these rootstocks were evaluated, represented by five plants each one, measured in five harvests from the third to seventh years after planting. Seven of them showed symptoms of CSD: Rangpur Otaheite orange 12901 (859, Rangpur Red Lime D.33.30 (866, Limão Cravo EEL (871, Rangpur Borneo red (874, Citrus kokhai (1649, Rough lemon 58329 (1655 and Limão Cravo x Swingle B (1695. For selection and breeding purposes, genetic and phenotypic parameters were estimated and individual genotypic values were predicted for all traits by the REML/BLUP (restricted maximum likelihood/best linear unbiased prediction procedure. The analysis of fruit production in five harvests showed selective accuracy of 84.59% revealing that a greater number of harvests is unnecessary. Selection of the best seven genotypes led to a genetic gain of 11.5% for fruit production while the selection of the very best genotype provided an estimated genetic gain of 16.3%. The higher predicted genetic means (>70.0 kg.pl-1 for fruit production were obtained for the genotypes Ipanema Rangpur Lime (1522, Santa Bárbara Red Lime (884

  17. Development and validation of a fast PCR-based detection method for pathogenic isolates of the citrus black spot fungus, Guignardia citricarpa

    NARCIS (Netherlands)

    Bonants, P.J.M.; Carroll, G.C.; Weerdt, de M.; Brouwershaven, van I.R.; Baayen, R.P.

    2003-01-01

    Based on the ITS regions of the ribosomal DNA, specific primer sets were developed for the citrus pathogen Guignardia citricarpa and the common citrus endophyte, G. mangiferae, and tested for their specificity against 37 isolates of G. citricarpa, 29 isolates of G. mangiferae, 10 isolates of related

  18. 不同砧木嫁接对西瓜生长发育及产量的影响%Effects of Different Rootstock on the Yield and Development of Citrullus lanatus var.lanatus

    Institute of Scientific and Technical Information of China (English)

    常高正; 张慎璞; 杨红丽; 赵卫星; 徐小利; 李晓慧; 张四普; 杨帆

    2009-01-01

    研究了豫园砧木王(Citrullus lanatus var.citroides cv.Yuyuanzhenmu)、超丰F1(Lagenaria siceraria cv.Chaofeng F1)、新土佐(Cucurbita maxima xC.moschata,Sintozwa)3个西瓜砧木嫁接对西瓜(Citrullus lanatus var.lanatus)生长发育、根系的分布及产量的影响.结果表明,3种不同砧木西瓜嫁接苗与自根苗相比,根系发达,茎叶生长旺盛,且有增产作用.其中豫园砧木王和新土佐砧木的嫁接效果最好,其能明显增强嫁接苗的长势,可分别使西瓜增产21.4%和25.0%.因此,建议选择豫园砧木王和新土佐嫁接西瓜为好,以达到丰产的目的.%Effects of Citrullus lanatus var. citroides cv. Yuyuanzhenmu,Lagenaria siceraria cv. Chaofeng Fl and Sintozwa (Cucurbita maxima ×C. moschata) on the development,distinction of the roots and the yield of C. lanatus var. lanatus were studied. The results showed that,compared with non-grafted seedling,the roots and shoots of the grafted seedlings with three rootstocks developed faster,and the yield increased. Of the three rootstocks,the grafting effect of C. lanatus var. citroides Yuyuanzhenmu and Sintozwa (Cucurbita maxima ×C. moschata) was better. The growth vigor and yields of grafted seedlings increased by 21.4% and 25.0% respectively. So,to grain high production,C. lanatus var. citroides Yuyuanzhenmu and Sintozwa (Cucurbita maxima ×C. moschata) were recommended to be used as rootstocks of C. lanatus var. lanatus.

  19. [Citrus boron nutrient level and its impact factors in the Three Gorges Reservoir region of Chongqing, China].

    Science.gov (United States)

    Zhou, Wei; Peng, Liang-Zhi; Chun, Chang-Pin; Jiang, Cai-Lun; Ling, Li-Li; Wang, Nan-Qi; Xing, Fei; Huang, Yi

    2014-04-01

    To investigate the level of boron nutrient in citrus and its impact factors, a total of 954 citrus leaf samples and 302 soil samples were collected from representative orchards in the 12 main citrus production counties in the Three Gorges Reservoir region of Chongqing to determine the boron content in citrus leaves, as well as the relationships between leaf boron content with soil available boron content, soil pH value, cultivar, rootstock and the age of tree. Results indicated that the leaf samples from 41.6% orchards (boron insufficient. The correlation of leaf boron content and soil available boron content was not significant. The soil pH, cultivar, rootstock and the age of tree did affect the leaf boron content. The leaves from the orchards with soil pH of 4.5-6.4 demonstrated significantly higher boron contents than with the soil pH of 6.5-8.5. The leaf boron contents in the different cultivars was ranged as Satsuma mandarin > pomelo > valencia orange > sweet orange > tangor > navel orange. The citrus on trifoliate orange and sour pomelo rootstocks had significantly higher leaf boron contents than on Carrizo citrange and red tangerine rootstocks. Compared with the adult citrus trees (above 8 year-old), 6.6% more of leaf samples of younger trees (3 to 8 year-old) contained boron contents in the optimum range (35-100 mg x kg(-1)).

  20. Trifoliata hybrids rootstocks for 'Lane Late' navel orange in Spain

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    Pilar Legua

    2011-10-01

    Full Text Available Carrizo citrange [Citrus sinensis (L. Osb. × Poncirus trifoliata (L. Raf.] and Cleopatra mandarin (C. reshni Hort. ex Tan. are the most important rootstocks used in Spain, but they are problematic and it is necessary to search for new rootstocks with better all-round performance. The performance of 'Lane Late' navel orange [Citrus sinensis (L. Osb] on ten rootstocks was determined in the South of the province of Alicante (Spain. They are Carrizo citrange, Cleopatra mandarin and eight new hybrids obtained at the Instituto Valenciano de Investigaciones Agrarias in Valencia (Spain: 020324 [Troyer citrange (C. sinensis × P. trifoliata × Cleopatra mandarin], Forner-Alcaide 418 (F&A 418 [Troyer citrange × common mandarin (C. deliciosa Ten.], Forner-Alcaide 13 (F&A 13, 030118, 030127 and 030131 (Cleopatra mandarin × P. trifoliata and 030212 and 030230 (Cleopatra mandarin × Troyer citrange. Soil is clay loam, with pH 8.5 and electric conductivity in the saturation extract at 25ºC of 5.79 mS cm-1. Yield was weighed during the first nine harvests, fruit quality was determined in the last three. Pre-harvest fruit-drop was controlled for the 4th until 9th harvests. The trees of 'Lane Late' navel budded on Cleopatra mandarin were the tallest (2.5 m and F&A 418 (1.6 m the shortest of all rootstocks tested. Trees on 030131 hybrid and Carrizo citrange rootstocks had the highest mean yield (81.2 and 80.3 kg per tree per year respectively, while trees on F&A 418 produced the lowest mean yield (22.3 kg per tree per year. Trees on 030131, 020324 and 030212 had the highest yield efficiency as total cumulative yield per cubic meter of canopy volume (62.1, 58.7 and 55.9 kg m-3 respectively whereas trees on 030127, F&A 418 and Cleopatra mandarin had lower yield efficiencies (45.0, 44.4 and 38.6 kg m-3, respectively. Pre-harvest fruit-drop was lower in trees grafted on Cleopatra mandarin (24.62 % and on 030212 (26.61 %, and was also low on F&A 418 (27

  1. Naringin and Neohesperidin Levels during Development of Leaves, Flower Buds, and Fruits of Citrus aurantium.

    Science.gov (United States)

    Castillo, J; Benavente, O; Del Río, J A

    1992-05-01

    The distribution of the flavanones naringin and neohesperidin has been analyzed during the development of the leaves, flower buds, and fruits of Citrus aurantium. These flavonoids are at maximum concentration in the organs studied during the logarithmic phase of growth, gradually decreasing until the organs reach maximum development. However, this decrease in the naringin and neohesperidin concentration in leaves, flower buds, and fruits is due to a dilution of the flavonoids caused by cell growth, because total content per organ continues to increase. The levels of neohesperidin are always greater than those of naringin, although the ratio between the relative concentrations is different in the three organs studied. Leaves have the highest ratios, varying between 8.83 and 5.18, followed by flowers (3.15-1.85), and fruits (2.23-1.02). These observations suggest different relationships between the respective enzymic activities in their biosynthetic pathway.

  2. Grapevine rootstock effects on scion sap phenolic levels, resistance to Xylella fastidiosa infection, and progression of Pierce’s disease

    Science.gov (United States)

    The xylem-limited bacterium Xylella fastidiosa (Xf) causes Pierce’s disease (PD), an important disease of grapevine, Vitis vinifera L. Grapevine rootstocks were developed to provide increased resistance to root disease, but rootstock effects on cane and vine diseases remain unclear. Grapevines that ...

  3. Development of a dense SNP-based linkage map of an apple rootstock progeny using the Malus Infinium whole genome genotyping array

    Directory of Open Access Journals (Sweden)

    Antanaviciute Laima

    2012-05-01

    Full Text Available Abstract Background A whole-genome genotyping array has previously been developed for Malus using SNP data from 28 Malus genotypes. This array offers the prospect of high throughput genotyping and linkage map development for any given Malus progeny. To test the applicability of the array for mapping in diverse Malus genotypes, we applied the array to the construction of a SNP-based linkage map of an apple rootstock progeny. Results Of the 7,867 Malus SNP markers on the array, 1,823 (23.2% were heterozygous in one of the two parents of the progeny, 1,007 (12.8% were heterozygous in both parental genotypes, whilst just 2.8% of the 921 Pyrus SNPs were heterozygous. A linkage map spanning 1,282.2 cM was produced comprising 2,272 SNP markers, 306 SSR markers and the S-locus. The length of the M432 linkage map was increased by 52.7 cM with the addition of the SNP markers, whilst marker density increased from 3.8 cM/marker to 0.5 cM/marker. Just three regions in excess of 10 cM remain where no markers were mapped. We compared the positions of the mapped SNP markers on the M432 map with their predicted positions on the ‘Golden Delicious’ genome sequence. A total of 311 markers (13.7% of all mapped markers mapped to positions that conflicted with their predicted positions on the ‘Golden Delicious’ pseudo-chromosomes, indicating the presence of paralogous genomic regions or mis-assignments of genome sequence contigs during the assembly and anchoring of the genome sequence. Conclusions We incorporated data for the 2,272 SNP markers onto the map of the M432 progeny and have presented the most complete and saturated map of the full 17 linkage groups of M. pumila to date. The data were generated rapidly in a high-throughput semi-automated pipeline, permitting significant savings in time and cost over linkage map construction using microsatellites. The application of the array will permit linkage maps to be developed for QTL analyses in a

  4. Development and characterization of genomic and expressed SSRs in citrus by genome-wide analysis.

    Directory of Open Access Journals (Sweden)

    Sheng-Rui Liu

    Full Text Available Microsatellites or simple sequence repeats (SSRs are one of the most popular sources of genetic markers and play a significant role in plant genetics and breeding. In this study, we identified citrus SSRs in the genome of Clementine mandarin and analyzed their frequency and distribution in different genomic regions. A total of 80,708 SSRs were detected in the genome with an overall density of 268 SSRs/Mb. While di-nucleotide repeats were the most frequent microsatellites in genomic DNA sequence, tetra-nucleotides, which had more repeat units than any other SSR types, had the highest cumulative sequence length. We identified 6,834 transcripts as containing 8,989 SSRs in 33,929 Clementine mandarin transcripts, among which, tri-nucleotide motifs (36.0% were the most common, followed by di-nucleotide (26.9% and hexa-nucleotide motifs (15.1%. The motif AG (16.7% was most abundant among these SSRs, while motifs AAG (6.6%, AAT (5.0%, and TAG (2.2% were most common among tri-nucleotides. Functional categorization of transcripts containing SSRs revealed that 5,879 (86.0% of such transcripts had homology with known proteins, GO and KEGG annotation revealed that transcripts containing SSRs were those implicated in diverse biological processes in plants, including binding, development, transcription, and protein degradation. When 27 genomic and 78 randomly selected SSRs were tested on Clementine mandarin, 95 SSRs revealed polymorphism. These 95 SSRs were further deployed on 18 genotypes of the three generas of Rutaceae for the genetic diversity assessment, genomic SSRs generally show low transferability in comparison to SSRs developed from expressed sequences. These transcript-markers identified in our study may provide a valuable genetic and genomic tool for further genetic research and varietal development in citrus, such as diversity study, QTL mapping, molecular breeding, comparative mapping and other genetic analyses.

  5. Development and characterization of genomic and expressed SSRs in citrus by genome-wide analysis.

    Science.gov (United States)

    Liu, Sheng-Rui; Li, Wen-Yang; Long, Dang; Hu, Chun-Gen; Zhang, Jin-Zhi

    2013-01-01

    Microsatellites or simple sequence repeats (SSRs) are one of the most popular sources of genetic markers and play a significant role in plant genetics and breeding. In this study, we identified citrus SSRs in the genome of Clementine mandarin and analyzed their frequency and distribution in different genomic regions. A total of 80,708 SSRs were detected in the genome with an overall density of 268 SSRs/Mb. While di-nucleotide repeats were the most frequent microsatellites in genomic DNA sequence, tetra-nucleotides, which had more repeat units than any other SSR types, had the highest cumulative sequence length. We identified 6,834 transcripts as containing 8,989 SSRs in 33,929 Clementine mandarin transcripts, among which, tri-nucleotide motifs (36.0%) were the most common, followed by di-nucleotide (26.9%) and hexa-nucleotide motifs (15.1%). The motif AG (16.7%) was most abundant among these SSRs, while motifs AAG (6.6%), AAT (5.0%), and TAG (2.2%) were most common among tri-nucleotides. Functional categorization of transcripts containing SSRs revealed that 5,879 (86.0%) of such transcripts had homology with known proteins, GO and KEGG annotation revealed that transcripts containing SSRs were those implicated in diverse biological processes in plants, including binding, development, transcription, and protein degradation. When 27 genomic and 78 randomly selected SSRs were tested on Clementine mandarin, 95 SSRs revealed polymorphism. These 95 SSRs were further deployed on 18 genotypes of the three generas of Rutaceae for the genetic diversity assessment, genomic SSRs generally show low transferability in comparison to SSRs developed from expressed sequences. These transcript-markers identified in our study may provide a valuable genetic and genomic tool for further genetic research and varietal development in citrus, such as diversity study, QTL mapping, molecular breeding, comparative mapping and other genetic analyses.

  6. Rootstock-regulated gene expression patterns associated with fire blight resistance in apple

    Directory of Open Access Journals (Sweden)

    Jensen Philip J

    2012-01-01

    Full Text Available Abstract Background Desirable apple varieties are clonally propagated by grafting vegetative scions onto rootstocks. Rootstocks influence many phenotypic traits of the scion, including resistance to pathogens such as Erwinia amylovora, which causes fire blight, the most serious bacterial disease of apple. The purpose of the present study was to quantify rootstock-mediated differences in scion fire blight susceptibility and to identify transcripts in the scion whose expression levels correlated with this response. Results Rootstock influence on scion fire blight resistance was quantified by inoculating three-year old, orchard-grown apple trees, consisting of 'Gala' scions grafted to a range of rootstocks, with E. amylovora. Disease severity was measured by the extent of shoot necrosis over time. 'Gala' scions grafted to G.30 or MM.111 rootstocks showed the lowest rates of necrosis, while 'Gala' on M.27 and B.9 showed the highest rates of necrosis. 'Gala' scions on M.7, S.4 or M.9F56 had intermediate necrosis rates. Using an apple DNA microarray representing 55,230 unique transcripts, gene expression patterns were compared in healthy, un-inoculated, greenhouse-grown 'Gala' scions on the same series of rootstocks. We identified 690 transcripts whose steady-state expression levels correlated with the degree of fire blight susceptibility of the scion/rootstock combinations. Transcripts known to be differentially expressed during E. amylovora infection were disproportionately represented among these transcripts. A second-generation apple microarray representing 26,000 transcripts was developed and was used to test these correlations in an orchard-grown population of trees segregating for fire blight resistance. Of the 690 transcripts originally identified using the first-generation array, 39 had expression levels that correlated with fire blight resistance in the breeding population. Conclusions Rootstocks had significant effects on the fire blight

  7. VARYING DEGREE OF GRAFTING COMPATIBILITY BETWEEN CV. CHARDONNAY, MERLOT AND DIFFERENT GRAPEVINE ROOTSTOCKS

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    Slavica TODIĆ

    2006-02-01

    Full Text Available Level of affi nity between grapevine rootstock and Vitis vinifera as scion, quality of reproductive materials and technological actions in grapevine rootstock production process determine success in grapevine rootstock production in large extent. Practical training showed that difference in level of compatibility between grapevine rootstock and grafted Vitis vinifera cultivars are existing. Direct effects of these differences are unequal yield of fi rst class grafted grapevine rootlings. In this paper, level of compatibility in nursery between clones of cv. Chardonnay BCL 75, VCR4 and cv. Merlot R18, MCL 519 and grapevine rootstocks Kober 5BB (Vitis berlandieri x V. riparia, SO4 (V. berlandieri x V. riparia and 41B (Chasselas x V.berlandieri were investigated. The trial was conducted in commercial grapevine nursery located in Velika Drenova, Serbia. As an index of compatibility, grade of high quality grapevine grafted rootlings, dry matter in mature shoots and root system development were used. Grafting was done by `tongue grafting` indoor technique. Stratifi cation was done in sand, on temperature of the stratifi cation material of 26-28oC, and humidity of around 90%. Grafted cuttings were waxed twice: before stratifi cation, and before planting in the nursery. Grafted rootlings were classed in two classes according to regulations of quality, (Yugoslav Offi cial Register, 26/79. Grafted rootlings that did not satisfi ed standard criteria were discarded. Both clones of cv. Chardonnay gave the highest percentage of I class grafted rootlings on grapevine rootstock 41B: clone BCL 75 – 60% and clone VCR4 – 61%. In the same combination, those grapevine grafted rootlings had the highest weight of the root system. Lower percentage of obtained I class grafted rootlings was established on rootstock Kober 5BB, while statistically signifi cantly lower yields were obtained on grapevine rootstock SO4: clone BCL75 – 43% and clone VCR4 – 48%. Dry

  8. Rootstock breeding in Prunus species: Ongoing efforts and new challenges

    Directory of Open Access Journals (Sweden)

    Felipe Gainza

    2015-08-01

    Full Text Available The current global agricultural challenges imply the need to generate new technologies and farming systems. In this context, rootstocks are an essential component in modern agriculture. Most currently used are those clonally propagated and there are several ongoing efforts to develop this type of plant material. Despite this tendency, lesser number of rootstock breeding programs exists in comparison to the large number of breeding programs for scion cultivars. In the case of rootstocks, traits evaluated in new selection lines are quite different: From the agronomic standpoint vigor is a key issue in order to establish high-density orchards. Other important agronomic traits include compatibility with a wide spectrum of cultivars from different species, good tolerance to root hypoxia, water use efficiency, aptitude to extract or exclude certain soil nutrients, and tolerance to soil or water salinity. Biotic stresses are also important: Resistance/tolerance to pests and diseases, such as nematodes, soil-borne fungi, crown gall, bacterial canker, and several virus, viroids, and phytoplasms. In this sense, the creation of new rootstocks at Centro de Estudios Avanzados en Fruticultura (CEAF offers an alternative to stone fruit crop, particularly in Chile, where just a few alternatives are commercially available, and there are site-specific problems. The implementation of molecular markers in order to give support to the phenotypic evaluation of plant breeding has great potential assisting the selection of new genotypes of rootstocks. Marker-Assisted Selection (MAS can shorten the time required to obtain new cultivars and can make the process more cost-effective than selection based exclusively on phenotype, but more basic research is needed to well understood the molecular and physiological mechanisms behind the studied trait.

  9. Budagovsky 9 rootstock: uncovering a novel resistance to fire blight

    Science.gov (United States)

    Budagovsky 9 (B.9) apple rootstock, displayed a high level of susceptibility (similar to M.9 rootstock) to fire blight bacteria (Erwinia amylovora) when leaves of non-grafted B.9 plants were inoculated. However, when older B.9 rootstock tissue was inoculated directly with E. amylovora, rootstock tis...

  10. Systemic resistance in citrus to Tetranychus urticae induced by conspecifics is transmitted by grafting and mediated by mobile amino acids.

    Science.gov (United States)

    Agut, Blas; Gamir, Jordi; Jaques, Josep A; Flors, Victor

    2016-10-01

    Recent research suggests that systemic signalling and communication between roots and leaves plays an important role in plant defence against herbivores. In the present study, we show that the oviposition of the two-spotted spider mite Tetranychus urticae in the systemic leaves of citrus rootstock Citrus aurantium (sour orange) was reduced by 50% when a lower leaf was previously infested with conspecifics. Metabolomic and gene expression analysis of the root efflux revealed a strong accumulation of glutamic acid (Glu) that triggered the expression of the citrus putative glutamate receptor (GRL) in the shoots. Additionally, uninfested sour orange systemic leaves showed increased expression of glutamate receptors and higher amounts of jasmonic acid (JA) and 12-oxo-phytodienoic acid in plants that were previously infested. Glu perception in the shoots induced the JA pathway, which primed LOX-2 gene expression when citrus plants were exposed to a second infestation. The spider mite-susceptible citrus rootstock Cleopatra mandarin (C. unshiu) also expressed systemic resistance, although the resistance was less effective than the resistance in sour orange. Surprisingly, the mobile signal in Cleopatra mandarin was not Glu, which suggests a strong genotype-dependency for systemic signalling in citrus. When the cultivar Clemenules (C. clementina) was grafted onto sour orange, there was a reduction in symptomatic leaves and T. urticae populations compared to the same cultivar grafted onto Cleopatra mandarin. Thus, systemic resistance is transmitted from the roots to the shoots in citrus and is dependent on rootstock resistance.

  11. 重庆市江津区柑橘产业发展现状与对策%Chongqing metro citrus industry development present situation and the countermeasures

    Institute of Scientific and Technical Information of China (English)

    何洪委; 代平

    2014-01-01

    The paper investigation and analysis of chongqing metro citrus industry development present situation, existing problems, and puts forward some countermeasures for development of citrus industry metro.%文章调查分析重庆市江津区柑橘产业发展现状、存在的问题,提出发展江津柑橘产业的对策。

  12. Breeding, genetic and genomic of citrus for disease resistance

    Directory of Open Access Journals (Sweden)

    Marcos A. Machado

    2011-10-01

    Full Text Available Although the citriculture is one of the most important economic activities in Brazil, it is based on a small number of varieties. This fact has contributed for the vulnerability of the culture regarding the phytosanitary problems. A higher number of varieties/genotypes with potential for commercial growing, either for the industry or fresh market, has been one of the main objectives of citrus breeding programs. The genetic breeding of citrus has improved, in the last decades, due to the possibility of an association between biotechnological tools and classical methods of breeding. The use of molecular markers for early selection of zygotic seedlings from controlled crosses resulted in the possibility of selection of a high number of new combination and, as a consequence, the establishment of a great number of hybrids in field experiments. The faster new tools are incorporated in the program, the faster is possibility to reach new genotypes that can be tested as a new variety. Good traits should be kept or incorporate, whereas bad traits have to be excluded or minimized in the new genotype. Scion and rootstock can not be considered separately, and graft compatibility, fruit quality and productivity are essential traits to be evaluated in the last stages of the program. The mapping of QTLs has favored breeding programs of several perennial species and in citrus it was possible to map several characteristics with qualitative and quantitative inheritance. The existence of linkage maps and QTLs already mapped, the development of EST and BAC library and the sequencing of the Citrus complete genome altogether make very demanding and urgent the exploration of such data to launch a wider genetic study of citrus. The rising of information on genome of several organisms has opened new approaches looking for integration between breeding, genetic and genome. Genome assisted selection (GAS involves more than gene or complete genome sequencing and is becoming

  13. Citrus Limonoids: Analysis, Bioactivity, and Biomedical Prospects

    Science.gov (United States)

    This publication is a review of the chemistry, biochemistry and bioactivity of limonoids occurring in citrus. The review chronologically relates the evolution of research in citrus limonoids beginning with their association with bitterness development in citrus juices. The chemical and biochemical...

  14. 两类柑桔杂种砧木对脐橙(Citrus sinensis Osbeck)幼树生长和叶片糖营养含量年变化的影响%Effects of Two Kinds of Rootstocks on the Growth of Navel Orange(Citrus sinensis Osbeck)Young Tree and the Annual Changes in the Contents of Carbohydrates in Leaves

    Institute of Scientific and Technical Information of China (English)

    周开兵; 郭文武; 夏仁学; 王贵元; 沈婷

    2004-01-01

    以体细胞杂种红桔+枳和红桔+粗柠檬、有性杂种Troyer枳橙和Swingle枳柚作砧木的耐湿脐橙(Citrus sinensis Osbeck)2年生嫁接苗为试材,通过盆栽试验研究了砧木对苗木生长和叶片糖营养含量年变化动态的影响.结果表明:红桔+枳的生长势和花量明显地强于和大于其它砧木,红桔+粗柠檬的生长和花量表现介于2种有性杂种之间.叶绿素a/b和类胡萝卜素含量在不同砧木间无显著差异,而不同砧木显著或极显著地影响叶绿素含量各指标.砧木影响叶片可溶性糖和淀粉含量年变化动态的基本特征.在休眠期,红桔+枳的可溶性糖和淀粉含量都高于2种有性杂种砧木,而红桔+粗柠檬则反之;在生长期,红桔+粗柠檬的可溶性糖和淀粉含量表现出高于有性杂种砧木的趋势,而红桔+枳则介于2种有性杂种砧木之间.同时还重点讨论了2种体细胞杂种砧木的利用价值.

  15. The potential for citrus cryotherapy

    Science.gov (United States)

    Citrus collections of pathogen-free plants are needed for breeding, research, and distribution to the user community. The Citrus Research Board funded research project “Development of cryotherapy as an improved method of eliminating graft transmissible pathogens in Citrus” sought to use cryotherapy,...

  16. Desenvolvimento de mudas de citros cultivadas em vaso em resposta à adubação NPK Development of citrus nursery trees grown in pots in response to NPK fertilization

    Directory of Open Access Journals (Sweden)

    Alberto Carlos de Campos Bernardi

    2000-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da adubação NPK sobre o desenvolvimento de mudas de laranjeira 'Valência' (Citrus sinensis sobre o porta-enxerto de limoeiro 'Cravo' (C. limonia em vasos com substrato de casca de Pinus, vermiculita e perlita. Utilizou-se um esquema de fatorial fracionário (1/55³ com um delineamento em blocos ao acaso. Os tratamentos consistiram em 5 doses (em g por planta de N: 1,25; 6,25; 11,25; 16,25; 21,25; 5 doses de K: 0,42; 3,75; 6,22; 9,34; 12,45; e 5 doses de P: 0,19; 0,89; 1,59; 2,29; 2,99. O N e o K foram fornecidos semanalmente, sendo 37,5% da dose para o porta-enxerto. O P foi fornecido totalmente no plantio. Avaliaram-se a produção de material seco das folhas, raízes, caule, parte aérea e total; área foliar, relação raízes/parte aérea; altura de plantas; volume radicular, relação área foliar/material seco para os porta-enxertos e as mudas, e o diâmetro do caule para os porta-enxertos. Funções de resposta foram ajustadas e os níveis de nutrientes foram calculados. Os resultados mostraram que as doses de fertilizantes que levaram às melhores respostas para produção de mudas de laranjeira 'Valência'/'Cravo' sobre o porta-enxertos de limoeiro 'Cravo' foram: N, 9,85; P, 2,86; K, 7,99 g por plantas.The objective of this research was to evaluate the NPK fertilizer effect on 'Valencia' sweet orange nursery tree (Citrus sinensis development, budded on Rangpur lime rootstocks (C. limonia in a protected environment using containers with Pinus bark, vermiculite and perlite substrates. The experiment consisted of a complete (1/5 5³ factorial randomized block design. Treatments comprised five concentrations in g per plant of N: 1.25; 6.25; 11.25; 16.25; 21.25; five concnetrations of K: 0.42; 3.75; 6.22; 9.34; 12.45; and five concentration of P: 0.19; 0.89; 1.59; 2.29; 2.99. Nitrogen and K were applieded weekly, and 37.5% of the total fertilization was applied to rootstocks. All P was

  17. Identification and transcript profiles of citrus growth-regulating factor genes involved in the regulation of leaf and fruit development.

    Science.gov (United States)

    Liu, Xiao; Guo, Ling-Xia; Jin, Long-Fei; Liu, Yong-Zhong; Liu, Tao; Fan, Yu-Hua; Peng, Shu-Ang

    2016-10-01

    Growth-regulating factor (GRF) is an important protein in GA-mediated response, with key roles in plant growth and development. However, it is not known whether or how the GRF proteins in citrus to regulate organ size. In this study, nine citrus GRF genes (CsGRF1-9) were validated from the 'Anliu' sweet orange (AL, Citrus sinensis cv. Anliu) by PCR amplification. They all contain two conserved motifs (QLQ and WRC) and have 3-4 exons. The transcript levels of genes were detected by qRT-PCR. Transcript analysis showed that (1) CsGRF 1, 2, 5, 6, 7, and 9 expressed predominantly in young leaf, CsGRF 3 and 4 expressed predominantly in fruit immature juice sacs and CsGRF 8 expressed predominantly in root; (2) all citrus GRF genes had significantly higher expression in young leaves than mature leaf; (3) in juice sacs, the transcript levels of CsGRF1, 4, 5, 6, and 8 increased significantly while the transcript levels of CsGRF2, 3, 7, and 9 had no significant change from 80 DAF to 100 DAF. Besides, GA3 treatment did not affect the transcript levels of CsGRF5 and CsGRF6 but significantly increased the transcript levels of the other seven CsGRF genes in young leaves. These results suggested that all CsGRF genes involve in the leaf development, CsGRF1, 4, 5, 6, and 8 act developmentally whilst CsGRF2, 3, 7, and 9 play fundamental roles in fruit cell enlargement, which may be through GA pathway or GA-independent pathway.

  18. Community Analysis of Arbuscular Mycorrhizal Fungi in Roots of Poncirus trifoliata and Citrus reticulata Based on SSU rDNA

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    Peng Wang

    2014-01-01

    Full Text Available Morphological observation of arbuscular mycorrhizal fungi (AMF species in rhizospheric soil could not accurately reflect the actual AMF colonizing status in roots, while molecular identification of indigenous AMF colonizing citrus rootstocks at present was rare in China. In our study, community of AMF colonizing trifoliate orange (Poncirus trifoliata L. Raf. and red tangerine (Citrus reticulata Blanco were analyzed based on small subunit of ribosomal DNA genes. Morphological observation showed that arbuscular mycorrhizal (AM colonization, spore density, and hyphal length did not differ significantly between two rootstocks. Phylogenetic analysis showed that 173 screened AMF sequences clustered in at least 10 discrete groups (GLO1~GLO10, all belonging to the genus of Glomus Sensu Lato. Among them, GLO1 clade (clustering with uncultured Glomus accounting for 54.43% clones was the most common in trifoliate orange roots, while GLO6 clade (clustering with Glomus intraradices accounting for 35.00% clones was the most common in red tangerine roots. Although, Shannon-Wiener indices exhibited no notable differences between both rootstocks, relative proportions of observed clades analysis revealed that composition of AMF communities colonizing two rootstocks varied severely. The results indicated that native AMF species in citrus rhizosphere had diverse colonization potential between two different rootstocks in the present orchards.

  19. Comportamento da laranjera 'Folha Murcha' em sete porta-enxertos no noroeste do Paraná Performance of 'Folha Murcha' orange on seven rootstocks in northwest of Parana

    Directory of Open Access Journals (Sweden)

    Neusa Maria Colauto Stenzel

    2005-12-01

    Full Text Available Este trabalho avaliou por um período de 14 anos, em Paranavaí-PR, o comportamento de plantas de laranjeira 'Folha Murcha' enxertadas nos porta-enxertos: limoeiros 'Cravo' (Citrus limonia, 'Rugoso da África' (Citrus jambhiri e 'Volkameriano' (Citrus volkameriana, citrangeiro 'C-13' (Citrus sinensis x Poncirus trifoliata, trifoliata (Poncirus trifoliata, tangerineiras 'Sunki' (Citrus sunki e 'Cleópatra' (Citrus reshni. O delineamento experimental utilizado foi o de blocos ao acaso, com sete tratamentos (porta-enxertos e quatro repetições, com três plantas por parcela. Os volumes das copas de plantas em tangerineira 'Cleópatra' e limoeiro 'Rugoso da África' foram significativamente maiores. Plantas em limoeiro 'Cravo' apresentaram a menor diferença entre os diâmetros dos troncos do porta-enxerto e da copa. A produção acumulada foi superior nas plantas em limoeiro 'Rugoso da África' e tangerineira 'Cleópatra' e menor em plantas sobre o trifoliata. A alternância da produção não foi acentuada nas plantas sobre os porta-enxertos avaliados. O teor de sólidos solúveis totais foi significativamente superior nos frutos obtidos de plantas enxertadas em trifoliata e menor em limoeiro 'Rugoso da África'. A qualidade do suco apresentou-se dentro dos padrões aceitáveis para variedades-copa de laranjeiras. A tangerineira 'Cleópatra' e o limoeiro 'Rugoso da África' são porta-enxertos promissores para a laranjeira 'Folha Murcha' nas condições avaliadas.This work evaluated for 14 years, in Paranavaí, PR, Brazil, the performance of 'Folha Murcha' orange trees budded on the following rootstocks: 'Rangpur' lime (Citrus limonia, 'African' rough lemon (Citrus jambhiri, 'Volkamer' lemon (Citrus volkameriana, 'C-13' citrange (Citrus sinensis × Poncirus trifoliata, trifoliate orange (Poncirus trifoliata, 'Sunki' mandarin (Citrus sunki and 'Cleopatra' mandarin (Citrus reshni. The experimental design was in blocks, with seven treatments

  20. Molecular characterization of Citrus tatter leaf virus historically associated with Meyer lemon trees: complete genome sequence and development of biologically active in vitro transcripts.

    Science.gov (United States)

    Tatineni, Satyanarayana; Afunian, Mohammad R; Hilf, Mark E; Gowda, Siddarame; Dawson, William O; Garnsey, Stephen M

    2009-04-01

    Citrus tatter leaf virus isolated from Meyer lemon trees (CTLV-ML) from California and Florida induces bud union incompatibility of citrus trees grafted on the widely used trifoliate and trifoliate hybrid rootstocks. The complete genome sequence of CTLV-ML was determined to be 6,495 nucleotides (nts), with two overlapping open reading frames (ORFs) and a poly (A) tail at the 3' end. The genome organization is similar to other capilloviruses, with ORF1 (nts 37 to 6,354) encoding a putative 242-kDa polyprotein which contains replication-associated domains plus a coat protein (CP), and ORF2 (nts 4,788 to 5,750), which is located within ORF1 in a different reading frame and encodes a putative movement protein. Although the proteins encoded by CTLV-ML possesses 84 to 96% amino acid sequence identity with strains of Apple stem grooving virus (ASGV), we observed two strikingly different regions in ORF1: variable region I (amino acids 532 to 570) and variable region II (amino acids 1,583 to 1,868), with only 15 to 18 and 56 to 62% identities, respectively, with the corresponding regions of ASGV strains. Conditions for a herbaceous systemic assay host were optimized in which the wild-type virus induced systemic infection in Phaseolus vulgaris cv. Light Red Kidney (LRK) bean plants at 19 or 22 degrees C but not at higher temperatures. In vitro transcripts generated from full-length cDNA clones induced systemic symptoms on LRK bean plants similar to that of the wild-type virus. Replication of the recombinant virus was confirmed by hybridization of a 5' positive-stranded RNA-specific probe to a genome-sized RNA and by reverse-transcription polymerase chain reaction.

  1. Development of genomic resources for Citrus clementina: Characterization of three deep-coverage BAC libraries and analysis of 46,000 BAC end sequences

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    Talon Manuel

    2008-09-01

    Full Text Available Abstract Background Citrus species constitute one of the major tree fruit crops of the subtropical regions with great economic importance. However, their peculiar reproductive characteristics, low genetic diversity and the long-term nature of tree breeding mostly impair citrus variety improvement. In woody plants, genomic science holds promise of improvements and in the Citrus genera the development of genomic tools may be crucial for further crop improvements. In this work we report the characterization of three BAC libraries from Clementine (Citrus clementina, one of the most relevant citrus fresh fruit market cultivars, and the analyses of 46.000 BAC end sequences. Clementine is a diploid plant with an estimated haploid genome size of 367 Mb and 2n = 18 chromosomes, which makes feasible the use of genomics tools to boost genetic improvement. Results Three genomic BAC libraries of Citrus clementina were constructed through EcoRI, MboI and HindIII digestions and 56,000 clones, representing an estimated genomic coverage of 19.5 haploid genome-equivalents, were picked. BAC end sequencing (BES of 28,000 clones produced 28.1 Mb of genomic sequence that allowed the identification of the repetitive fraction (12.5% of the genome and estimation of gene content (31,000 genes of this species. BES analyses identified 3,800 SSRs and 6,617 putative SNPs. Comparative genomic studies showed that citrus gene homology and microsyntheny with Populus trichocarpa was rather higher than with Arabidopsis thaliana, a species phylogenetically closer to citrus. Conclusion In this work, we report the characterization of three BAC libraries from C. clementina, and a new set of genomic resources that may be useful for isolation of genes underlying economically important traits, physical mapping and eventually crop improvement in Citrus species. In addition, BAC end sequencing has provided a first insight on the basic structure and organization of the citrus genome and has

  2. PERFORMANCE OF ‘TUXPAN VALENCIA’ SWEET ORANGE GRAFTED ONTO 14 ROOTSTOCKS IN NORTHERN BAHIA, BRAZIL

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    NATIANA DE OLIVEIRA FRANÇA

    Full Text Available ABSTRACT In the State of Bahia, Brazil, the citrus industry is located on the north coast with the prevalence of the combination ‘Pera’ sweet orange on ‘Rangpur’ lime. Scion-rootstock diversification may contribute to the increase of yield and the extension of harvest season, as long as to decrease the risk associated to abiotic and biotic stresses. Therefore, the performance of ‘Tuxpan Valencia’ sweet orange grafted onto 14 rootstocks was evaluated in Rio Real – BA. Planting was performed in 2006 under rainfed cultivation on cohesive ultisol and tree spacing of 6.0 m x 4.0 m. Tree size, yield and fruit quality were evaluated in the period of 2010-2014, in addition to tree survival at nine years old and drought tolerance in the field based on leaf wilting. In the evaluated conditions, ‘Sunki Tropical’ and ‘Sunki Maravilha’ mandarins led to the highest scion canopy volume. The highest accumulated yield in five harvests was recorded on ‘Santa Cruz Rangpur’ lime, ‘Volkamer’ lemon, ‘Riverside’ and ‘Indio’ citrandarins, ‘Sunki Tropical’ mandarin and the hybrid TSKC x (LCR x TR – 001. ‘Riverside’ and TSKFL x CTSW – 049 induced higher yield efficiency on the canopy. The rootstocks did not influence the tree survival nine years after planting except for lower survival of TSKFL x CTSW – 049. Drought tolerance was not affected either. Regarding to the fruit quality of ‘Tuxpan Valencia’, the rootstocks influenced the juice content, soluble solids and technological index with the citrandarins, ‘Santa Cruz Rangpur’ lime, ‘Volkamer’ lemon and ‘Sunki Tropical’ mandarin presenting higher performance in general.

  3. THE GROWTH PERFORMANCE OF CITRUS DERIVED FROM SOMATIC EMBRYOGENESIS PLANTLET AND SCION STOCK

    Directory of Open Access Journals (Sweden)

    Nirmala Friyanti Devy

    2014-10-01

    Full Text Available Somatic embryogenesis (SE of callus culture in vitro is one of citrus propagation ways for producing free virus and genetically true-to-type plantlets. To induce growing of plantlets derived from this technology, they should be grafted ex vitro onto a citrus rootstock. The research aimed to evaluate the growth performance of citrus plants cv. Siam Kintamani (Citrus nobilis L. that used both plantlets and scions as their stocks. The research was conducted at Tlekung Research Station, Indonesian Citrus and Subtropical Fruit Research Institute from June 2011 to December 2012. The treatments were done at nursery house by grafting a plantlet and budding a scion onto an eight-month-old Japanese Citroon (JC rootstock plant. The grafted and budded plants of one-year old were maintained at nursery house then transplanted into the field. In the field, the research was arranged in a randomized block design with three replications and used 15 plants as unit samples. The results showed that the vegetative growth of Siam Kintamani seedling derived from SE or grafted plant was faster than that of budded plant started from 10 to 12 months after treatment in the nersery house. In the field, the growth of SE grafted plant was only significantly different up to 6 months after transplanting. Plantlets produced from SE in vitro propagation can be used as a good alternative stock material for producing healthy citrus plants. Therefore, a further research is required especially on varieties used, reproductive growth and massive planlets production.

  4. Heat shock transcription factors expression during fruit development and under hot air stress in Ponkan (Citrus reticulata Blanco cv. Ponkan) fruit.

    Science.gov (United States)

    Lin, Qiong; Jiang, Qing; Lin, Juanying; Wang, Dengliang; Li, Shaojia; Liu, Chunrong; Sun, Chongde; Chen, Kunsong

    2015-04-01

    Heat shock transcription factors (Hsfs) play a role in plant responses to stress. Citrus is an economically important fruit whose genome has been fully sequenced. So far, no detailed characterization of the Hsf gene family is available for citrus. A genome-wide analysis was carried out in Citrus clementina to identify Hsf genes, named CcHsfs. Eighteen CcHsfs were identified and classified into three main clades (clades A, B and C) according to the structural characteristics and the phylogenetic comparison with Arabidopsis and tomato. MEME motif analysis highlighted the conserved DBD and HR-A/B domains, which were similar to Hsf protein structures in other species. Gene expression analysis in Ponkan (Citrus reticulata Blanco cv. Ponkan) fruit identified 14 Hsf genes, named CrHsf, as important candidates for a role in fruit development and ripening, and showed seven genes to be expressed in response to hot air stress. CrHsfB2a and CrHsfB5 were considered to be important regulators of citrate content and showed variation in both developmentally-related and hot air-triggered citrate degradation processes. In summary, the data obtained from this investigation provides the basis for further study to dissect Hsf function during fruit development as well as in response to heat stress and also emphasizes the potential importance of CrHsfs in regulation of citrate metabolism in citrus fruit.

  5. Comportamento da laranjeira 'Valência' sobre seis porta-enxertos no noroeste do Paraná Behavior of 'Valencia' orange tree on six rootstocks in the northwest of Parana state

    Directory of Open Access Journals (Sweden)

    Pedro Antonio Martins Auler

    2008-03-01

    Full Text Available Com o objetivo de identificar alternativas ao uso do limoeiro 'Cravo', avaliou-se a influência de porta-enxertos na produtividade e nas características físico-químicas dos frutos de laranjeira 'Valência' em experimento instalado em janeiro de 1994, sem irrigação, no município de Nova Esperança-PR. Adotou-se delineamento experimental em blocos ao acaso, com quatro repetições, três plantas úteis por parcela e seis porta-enxertos como tratamentos: limoeiro 'Cravo' (C. limonia, tangerineira 'Cleópatra' (C. reshni e 'Sunki' (C. sunki, citrangeiro 'Troyer' (P. trifoliata x C. sinensis, tangeleiro 'Orlando' (C. tangerina x C. paradisi e laranjeira 'Caipira' (C. sinensis. Avaliou-se a qualidade dos frutos em duas safras (2002 e 2005, o desenvolvimento vegetativo e a eficiência de produção em 1999 e 2003, e a produção (1996 a 2005. Em relação ao 'Cravo', a 'Sunki' induziu maior produção e volume de copa, e eficiência de produção e qualidade do fruto equivalentes; o 'Troyer' induziu eficiência de produção equivalente, frutos com rendimento industrial superior e peso médio inferior; a 'Cleópatra' induziu produção equivalente, eficiência de produção inferior e maior volume de copa. O estudo mostrou que os porta-enxertos 'Sunki', 'Cleópatra' e 'Troyer' se destacaram como opções para a diversificação do 'Cravo'.In order to identify alternatives to the utilization of 'Rangpur' lime, the major rootstock cultivar used in citrus orchards, an experiment was conducted in a field established in 1994 in Nova Esperança, Paraná, Brazil and maintained without irrigation. Six rootstock cultivars were tested in relation to yield and physico-chemical characteristics of 'Valencia" fruits: 'Rangpur'lime (C. limonia, 'Cleopatra' (C. reshni and 'Sunki' (C. sunki mandarins, 'Troyer' citrange (P. trifoliata x C. sinensis, 'Orlando' tangelo (C. tangerina x C. paradisi and 'Caipira' orange (C. sinensis. The complete randomized block

  6. Regeneration systems for pyramiding disease resistance into walnut rootstocks

    Science.gov (United States)

    This study was conducted to regenerate selected walnut rootstocks adventitiously. This is an essential step to be able to produce transgenic walnut rootstocks with superior traits, such as disease resistance. A series of plant tissue culture experiments were conducted on RX1 and VX211 rootstocks wit...

  7. Evaluating paradox walnut rootstocks for resistance to Armillaria root disease

    Science.gov (United States)

    The most common Juglans regia (English walnut) rootstock in California is Paradox, a hybrid between J. hindsii (Northern California black walnut) and J. regia. Unfortuntely, Paradox rootstock is highly susceptible to Armillaria root disease. The relative resistance of new clonal, Paradox rootstock...

  8. Silencing abnormal wing disc gene of the Asian citrus psyllid, Diaphorina citri disrupts adult wing development and increases nymph mortality.

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    Ibrahim El-Shesheny

    Full Text Available Huanglongbing (HLB causes considerable economic losses to citrus industries worldwide. Its management depends on controlling of the Asian citrus Psyllid (ACP, the vector of the bacterium, Candidatus Liberibacter asiaticus (CLas, the causal agent of HLB. Silencing genes by RNA interference (RNAi is a promising tool to explore gene functions as well as control pests. In the current study, abnormal wing disc (awd gene associated with wing development in insects is used to interfere with the flight of psyllids. Our study showed that transcription of awd is development-dependent and the highest level was found in the last instar (5(th of the nymphal stage. Micro-application (topical application of dsRNA to 5(th instar of nymphs caused significant nymphal mortality and adult wing-malformation. These adverse effects in ACP were positively correlated with the amounts of dsRNA used. A qRT-PCR analysis confirmed the dsRNA-mediated transcriptional down-regulation of the awd gene. Significant down-regulation was required to induce a wing-malformed phenotype. No effect was found when dsRNA-gfp was used, indicating the specific effect of dsRNA-awd. Our findings suggest a role for awd in ACP wing development and metamorphosis. awd could serve as a potential target for insect management either via direct application of dsRNA or by producing transgenic plants expressing dsRNA-awd. These strategies will help to mitigate HLB by controlling ACP.

  9. 2015 Progress Report – Evaluation of the Cornell-Geneva Apple Rootstocks and Other Promising Apple Rootstocks

    Science.gov (United States)

    A number of new apple rootstocks from the Cornell/USDA apple rootstock breeding project, located at Geneva, NY which are resistant to fire blight are rapidly becoming available to the industry. These rootstocks are also dwarfing, tolerant to replant disease and productive. Data on cumulative yield...

  10. Two previously unknown Phytophthora species associated with brown rot of Pomelo (Citrus grandis) fruits in Vietnam

    Science.gov (United States)

    Schena, Leonardo; Jung, Thomas; Evoli, Maria; Pane, Antonella; Van Hoa, Nguyen; Van Tri, Mai; Wright, Sandra; Ramstedt, Mauritz; Olsson, Christer; Faedda, Roberto; Magnano di San Lio, Gaetano

    2017-01-01

    Two distinct Phytophthora taxa were found to be associated with brown rot of pomelo (Citrus grandis), a new disease of this ancestral Citrus species, in the Vinh Long province, Mekong River Delta area, southern Vietnam. On the basis of morphological characters and using the ITS1-5.8S-ITS2 region of the rDNA and the cytochrome oxidase subunit 1 (COI) as barcode genes, one of the two taxa was provisionally named as Phytophthora sp. prodigiosa, being closely related to but distinct from P. insolita, a species in Phytophthora Clade 9, while the other one, was closely related to but distinct from the Clade 2 species P. meadii and was informally designated as Phytophthora sp. mekongensis. Isolates of P. sp. prodigiosa and P. sp. mekongensis were also obtained from necrotic fibrous roots of Volkamer lemon (C. volkameriana) rootstocks grafted with ‘King’ mandarin (Citrus nobilis) and from trees of pomelo, respectively, in other provinces of the Mekong River Delta, indicating a widespread occurrence of both Phytophthora species in this citrus-growing area. Koch’s postulates were fulfilled via pathogenicity tests on fruits of various Citrus species, including pomelo, grapefruit (Citrus x paradisi), sweet orange (Citrus x sinensis) and bergamot (Citrus x bergamia) as well as on the rootstock of 2-year-old trees of pomelo and sweet orange on ‘Carrizo’ citrange (C. sinensis ‘Washington Navel’ x Poncirus trifoliata). This is the first report of a Phytophthora species from Clade 2 other than P. citricola and P. citrophthora as causal agent of fruit brown rot of Citrus worldwide and the first report of P. insolita complex in Vietnam. Results indicate that likely Vietnam is still an unexplored reservoir of Phytophthora diversity. PMID:28208159

  11. Breeding rootstocks for Prunus species: Advances in genetic and genomics of peach and cherry as a model

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    Verónica Guajardo

    2015-08-01

    Full Text Available Prunus rootstock is an important choice in optimizing productivity of grafted cultivars. Nevertheless, many Prunus rootstocks are notoriously intolerant to hypoxia which is caused by waterlogging and/or heavy soils. There is no available information to help select Prunus rootstocks that are tolerant to stress conditions such as root hypoxia caused by excess moisture. Information from genetic maps has demonstrated a high level of synteny among Prunus species, and this suggests that they all share a similar genomic structure. It should be possible to identify the genetic determinants involved in tolerance to hypoxia and other traits in Prunus rootstocks by applying methods to identify regions of the genome involved in the expression of important traits; these have been developed mainly in peach which is the model species for the genus. Molecular markers that are tightly linked to major genes would be useful in marker-assisted selection (MAS to optimize new rootstock selection. This article provides insight on the advances in the development of molecular markers, genetic maps, and gene identification in Prunus, mainly in peach; the aim is to provide a general approach for identifying the genetic determinants of hypoxia stress in rootstocks.

  12. Porta-enxertos para a lima-ácida-'Tahiti' na região de Bebedouro, SP Rootstocks for 'Tahiti' acid lime in Bebedouro region, SP, Brazil

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    JOSÉ ORLANDO DE FIGUEIREDO

    2002-04-01

    Full Text Available Foi instalado um experimento de seleção de porta-enxertos para a lima-ácida-'Tahiti' (Citrus latifolia Tanaka, em dezembro de 1988, na Estação Experimental de Citricultura de Bebedouro-SP, com o objetivo de conhecer seu comportamento e oferecer novas opções de plantio para as condições ecológicas semelhantes às daquela região. A variedade copa, originária do BAG-Citros do IAC, localizado no Centro de Citricultura Sylvio Moreira, Cordeirópolis-SP, é um clone nucelar de 'Tahiti', denominado IAC-5. Os porta-enxertos, que tiveram a mesma origem, foram: tangerinas-'Sunki' (Citrus sunki Hort. ex Tanaka; 'Cleópatra'(Citrus reshni Hort. ex Tan.; 'Batangas' e 'Oneco' (Citrus reticulata Blanco; trifoliata-EEL (Poncirus trifoliata Raf.; limão-'Cravo' (Citrus limonia Osbeck; limão-'Volkameriano Catania 2' (Citrus volkameriana Tan. & Pasq.; tangelo-'Orlando' (C. reticulata Blanco x Citrus paradisi Macf.; citrumelo-'Swingle' (P. trifoliata Raf. X C.paradisi Macf.; citrange-'Morton' (P. trifoliata Raf. X C. sinensis (L. Osbeck e laranja-'Caipira DAC' (C. sinensis (L. Osbeck. Com relação à produção, avaliada no período de 1991 a 1998, os porta-enxertos de melhor comportamento foram o tangelo-'Orlando', citrange-'Morton' e citrumelo-'Swingle'. As mais baixas produções ocorreram nos porta-enxertos de tangerina e de laranja-'Caipira DAC'. O limão-'Cravo' apresentou produção intermediária e proporcionou curta vida útil às plantas.In 1988 an experiment was established in Bebedouro, SP (Brazil, in order to evaluate eleven rootstocks for 'Tahiti' lime (Citrus latifolia Tanaka. Scion variety was the IAC 5 cultivar, from IAC germplasm bank at Cordeirópolis, SP; all rootstocks were also obtained at that institution. A randomized blocks design was used as statistical model, with eleven blocks and one plant per treatment. The eleven treatments were: 'Sunki' (Citrus sunki Hort. ex Tanaka, 'Cleópatra'(Citrus reshni Hort. ex Tan., 'Batangas

  13. Engineering cherry rootstocks with resistance to Prunus necrotic ring spot virus through RNAi-mediated silencing.

    Science.gov (United States)

    Song, Guo-qing; Sink, Kenneth C; Walworth, Aaron E; Cook, Meridith A; Allison, Richard F; Lang, Gregory A

    2013-08-01

    Prunus necrotic ringspot virus (PNRSV) is a major pollen-disseminated ilarvirus that adversely affects many Prunus species. In this study, an RNA interference (RNAi) vector pART27-PNRSV containing an inverted repeat (IR) region of PNRSV was transformed into two hybrid (triploid) cherry rootstocks, 'Gisela 6' (GI 148-1) and 'Gisela 7'(GI 148-8)', which are tolerant and sensitive, respectively, to PNRSV infection. One year after inoculation with PNRSV plus Prune Dwarf Virus, nontransgenic 'Gisela 6' exhibited no symptoms but a significant PNRSV titre, while the transgenic 'Gisela 6' had no symptoms and minimal PNRSV titre. The nontransgenic 'Gisela 7' trees died, while the transgenic 'Gisela 7' trees survived. These results demonstrate the RNAi strategy is useful for developing viral resistance in fruit rootstocks, and such transgenic rootstocks may have potential to enhance production of standard, nongenetically modified fruit varieties while avoiding concerns about transgene flow and exogenous protein production that are inherent for transformed fruiting genotypes.

  14. COMPATIBILITY AND FEASIBILITY OF GRAFT TOMATO CULTIVAR SANTA CRUZ KADA IN DIFFERENT ROOTSTOCKS

    Directory of Open Access Journals (Sweden)

    A. R. Zeist

    2015-02-01

    Full Text Available Tomato production through the technique of grafting aims to control soil pathogens, induce flowering, and improve tolerance to waterlogging, salinity and alkalinity of the soil. For this work were performed 50 grafts for each type of rootstock, totaling 100 slips and 50 seedlings kept as control. After 15 days of grafting, the seedlings were evaluated on the percentage of picks grafting. The treatment which used the tomato cultivar Cherry Red® as rootstock presented results of vegetative growth (height and volume Cup higher than other treatments. However after transplanting, defective development was observed for plants with grafting when compared to the controls. After 35 days of follow up, there was a low survival rate, being 5% of the plants. According to the results obtained in this work the tomato cultivar Santa Cruz Kada® has good compatibility with the rootstock cultivar Cayenne® pepper and tomato cultivar Cherry Red®

  15. Tetraploidization events by chromosome doubling of nucellar cells are frequent in apomictic citrus and are dependent on genotype and environment

    Science.gov (United States)

    Aleza, Pablo; Froelicher, Yann; Schwarz, Sergio; Agustí, Manuel; Hernández, María; Juárez, José; Luro, François; Morillon, Raphael; Navarro, Luis; Ollitrault, Patrick

    2011-01-01

    tetraploidization. Tetraploid genotypes arising from chromosome doubling of apomictic citrus are extensively being used as parents in breeding programmes to develop seedless triploid cultivars and have potential direct use as new rootstocks. PMID:21586529

  16. Citrus leprosis research update

    Science.gov (United States)

    Citrus leprosis is one of the oldest citrus diseases, but is also one of the most important emerging citrus diseases in South and Central America, and it is apparently spreading northward towards the U.S. Research in our labs and by others has shown that citrus leprosis disease is caused by a compl...

  17. Porta-enxertos para a tangerineira 'Michal' no Rio Grande do Sul Rootstocks for 'Michal' tangerine in Rio Grande do Sul - Brazil

    Directory of Open Access Journals (Sweden)

    Eduardo Cesar Brugnara

    2009-08-01

    Full Text Available A tangerineira 'Michal' (Citrus clementina x C. tangerina poderá ser uma boa alternativa ao Rio Grande do Sul como cultivar copa para produção de frutos em época precoce. No entanto, há falta de informações sobre seu comportamento em cultivo nas condições ambientais desse Estado. O objetivo deste trabalho foi avaliar o desenvolvimento das plantas, a produção e a qualidade dos frutos da tangerineira 'Michal' enxertada sobre cinco porta-enxertos: citrangeiro 'Troyer', citrumeleiro 'Swingle', limoeiro 'Cravo', tangerineira 'Sunki' e trifoliata 'Flying Dragon', na Depressão Central do Rio Grande do Sul. Foram avaliados os seguintes parâmetros: a altura das plantas, a circunferência do tronco, a área de projeção da copa (APC, o número e a massa (MF de frutos produzidos, a relação MF/APC (IP, o teor de sólidos solúveis totais (SST, a acidez total titulável (ATT e a relação SST/ATT do suco, além do tamanho dos frutos e do rendimento de suco. O citrumeleiro 'Swingle' promoveu bom vigor, boa produção, bom IP, bons níveis de SST e de ATT da 'Michal', enquanto o limoeiro 'Cravo' conferiu bom vigor, boa produção, bom IP e bom tamanho dos frutos, ambos podendo ser indicados como porta-enxertos em pomares de tangerineira 'Michal'.'Michal' tangerine (Citrus clementina x C. tangerina can be a good choice as canopy for early maturing fruit production in Rio Grande do Sul. The limitation is the lack of information about its performance and management. The aim of this research was to evaluate the development, production and fruit quality of 'Michal' tangerine grafted on five rootstocks: 'Troyer' citrange, 'Swingle' citrumelo, 'Cravo' lemon, 'Sunki' tangerine and 'Flying Dragon' trifoliate orange, in the Depressão Central of Rio Grande do Sul. The following variables were evaluated: plant height; trunk circumference; canopy projection area (APC; produced fruit number and weight (MF; MF/APC relation (IP; juice total soluble solids

  18. The Geneva apple rootstock breeding program

    Science.gov (United States)

    The ancient practice of clonal propagation of perennial fruit crops by means of grafting was transformed when humans realized that certain properties of selected root systems could be beneficial for increasing productivity of that fruit crop. Certain clonal apple rootstocks were recognized for their...

  19. Unique characteristics of Geneva apple rootstocks

    Science.gov (United States)

    The Geneva® apple rootstock breeding program has been operating since the early 1970’s. It is a unique program in that it had access to important germplasm resources that later became the USDA ARS apple collection in Geneva, NY. This genetic diversity allowed for the achievement of one of the proj...

  20. Ultralow oxygen treatment for control of Planococcus ficus (Homoptera: Pseudococcidae) on grape rootstocks

    Science.gov (United States)

    Controlled atmosphere with ultralow oxygen (ULO) treatments for control of vine mealybug, Planococcus ficus Signoret (Homoptera: Pseudococcidae), on grape rootstocks were developed successfully. Two ULO treatments with 30 ppm oxygen, 3 days at 25'C and 4 days at 15'C, achieved complete control of a...

  1. Fine Mapping for Identification of Citrus Alternaria Brown Spot Candidate Resistance Genes and Development of New SNP Markers for Marker-Assisted Selection

    Science.gov (United States)

    Cuenca, Jose; Aleza, Pablo; Garcia-Lor, Andres; Ollitrault, Patrick; Navarro, Luis

    2016-01-01

    Alternaria brown spot (ABS) is a serious disease affecting susceptible citrus genotypes, which is a strong concern regarding citrus breeding programs. Resistance is conferred by a recessive locus (ABSr) previously located by our group within a 3.3 Mb genome region near the centromere in chromosome III. This work addresses fine-linkage mapping of this region for identifying candidate resistance genes and develops new molecular markers for ABS-resistance effective marker-assisted selection (MAS). Markers closely linked to ABSr locus were used for fine mapping using a 268-segregating diploid progeny derived from a heterozygous susceptible × resistant cross. Fine mapping limited the genomic region containing the ABSr resistance gene to 366 kb, flanked by markers at 0.4 and 0.7 cM. This region contains nine genes related to pathogen resistance. Among them, eight are resistance (R) gene homologs, with two of them harboring a serine/threonine protein kinase domain. These two genes along with a gene encoding a S-adenosyl-L-methionine-dependent-methyltransferase protein, should be considered as strong candidates for ABS-resistance. Moreover, the closest SNP was genotyped in 40 citrus varieties, revealing very high association with the resistant/susceptible phenotype. This new marker is currently used in our citrus breeding program for ABS-resistant parent and cultivar selection, at diploid, triploid and tetraploid level. PMID:28066498

  2. Development and systematic validation of qPCR assays for rapid and reliable differentiation of Xylella fastidiosa strains causing citrus variegated chlorosis.

    Science.gov (United States)

    Li, Wenbin; Teixeira, Diva C; Hartung, John S; Huang, Qi; Duan, Yongping; Zhou, Lijuan; Chen, Jianchi; Lin, Hong; Lopes, Silvio; Ayres, A Juliano; Levy, Laurene

    2013-01-01

    The xylem-limited, Gram-negative, fastidious plant bacterium Xylella fastidiosa is the causal agent of citrus variegated chlorosis (CVC), a destructive disease affecting approximately half of the citrus plantations in the State of São Paulo, Brazil. The disease was recently found in Central America and is threatening the multi-billion U.S. citrus industry. Many strains of X. fastidiosa are pathogens or endophytes in various plants growing in the U.S., and some strains cross infect several host plants. In this study, a TaqMan-based assay targeting the 16S rDNA signature region was developed for the identification of X. fastidiosa at the species level. Another TaqMan-based assay was developed for the specific identification of the CVC strains. Both new assays have been systematically validated in comparison with the primer/probe sets from four previously published assays on one platform and under similar PCR conditions, and shown to be superior. The species specific assay detected all X. fastidiosa strains and did not amplify any other citrus pathogen or endophyte tested. The CVC-specific assay detected all CVC strains but did not amplify any non-CVC X. fastidiosa nor any other citrus pathogen or endophyte evaluated. Both sets were multiplexed with a reliable internal control assay targeting host plant DNA, and their diagnostic specificity and sensitivity remained unchanged. This internal control provides quality assurance for DNA extraction, performance of PCR reagents, platforms and operators. The limit of detection for both assays was equivalent to 2 to 10 cells of X. fastidiosa per reaction for field citrus samples. Petioles and midribs of symptomatic leaves of sweet orange harbored the highest populations of X. fastidiosa, providing the best materials for detection of the pathogen. These new species specific assay will be invaluable for molecular identification of X. fastidiosa at the species level, and the CVC specific assay will be very powerful for the

  3. The WRKY Transcription Factor Family in Citrus: Valuable and Useful Candidate Genes for Citrus Breeding.

    Science.gov (United States)

    Ayadi, M; Hanana, M; Kharrat, N; Merchaoui, H; Marzoug, R Ben; Lauvergeat, V; Rebaï, A; Mzid, R

    2016-10-01

    WRKY transcription factors belong to a large family of plant transcriptional regulators whose members have been reported to be involved in a wide range of biological roles including plant development, adaptation to environmental constraints and response to several diseases. However, little or poor information is available about WRKY's in Citrus. The recent release of completely assembled genomes sequences of Citrus sinensis and Citrus clementina and the availability of ESTs sequences from other citrus species allowed us to perform a genome survey for Citrus WRKY proteins. In the present study, we identified 100 WRKY members from C. sinensis (51), C. clementina (48) and Citrus unshiu (1), and analyzed their chromosomal distribution, gene structure, gene duplication, syntenic relation and phylogenetic analysis. A phylogenetic tree of 100 Citrus WRKY sequences with their orthologs from Arabidopsis has distinguished seven groups. The CsWRKY genes were distributed across all ten sweet orange chromosomes. A comprehensive approach and an integrative analysis of Citrus WRKY gene expression revealed variable profiles of expression within tissues and stress conditions indicating functional diversification. Thus, candidate Citrus WRKY genes have been proposed as potentially involved in fruit acidification, essential oil biosynthesis and abiotic/biotic stress tolerance. Our results provided essential prerequisites for further WRKY genes cloning and functional analysis with an aim of citrus crop improvement.

  4. Effect of saline conditions on the maturation process of Clementine clemenules fruits on two different rootstocks

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, J. M.; Gomez-Gomez, A.; Perez-Perez, J. G.; Botia, P.

    2010-07-01

    The production of mandarins is important in the Mediterranean area, where the continued use of saline water reduces fruit yield and modifies fruit quality. Grafted trees of Clemenules mandarin scion on Carrizo citrange and Cleopatra mandarin rootstocks, two of the most common citrus rootstocks employed in this area, were irrigated with two saline treatments (control and 30 mM NaCl). The fruit quality was studied through the last two months before the fruit harvest. Salinity reduced both the fruit number and the mean fruit weight on Carrizo trees whereas no fruit weight reduction was observed on Cleopatra. The decrease of fruit weight on Carrizo trees is probably due to the lower water content and consequently the lower juice percentage. Although the saline treatment produced significant differences in some fruit quality variables (shape and thickness indices) throughout the maturation process, they were minimal at the harvest time. Total soluble solids (TSS) were significantly higher in fruits from the saline treatments, probably due to a passive dehydration. It is also possible that de novo synthesis of sugars occurred, since fruits from Cleopatra trees receiving the saline treatment had similar water contents but higher TSS than control fruits. The external fruit colour indicated that the saline treatment accelerated the maturation process; however, the maturity index showed that the high acidity of these fruits delayed the internal maturation with respect to the control fruits. (Author) 41 refs.

  5. Desenvolvimento de porta-enxertos de umbuzeiro em resposta à adubação com nitrogênio e fósforo ‘Umbuzeiro’ rootstocks development as a answer for fertilization with nitrogen and phosphorous

    Directory of Open Access Journals (Sweden)

    Alberto Soares de Melo

    2005-04-01

    Full Text Available A adubação, notadamente com nitrogênio e fósforo, é fundamental no estádio de desenvolvimento inicial de mudas de frutíferas. Porém, existem poucas informações científicas com respeito do umbuzeiro. Assim, objetivou-se avaliar o efeito de doses de nitrogênio e fósforo no desenvolvimento de porta-enxertos de umbuzeiro (Spondias tuberosa Arr. Câm.. O experimento foi conduzido sob telado, na Universidade Federal de Sergipe, em um delineamento em blocos ao acaso, em esquema fatorial 4 x 4, sendo quatro níveis de nitrogênio e quatro de fósforo (0, 50, 100 e 150kg ha-1 de N e P2O5, respectivamente na forma de uréia e superfosfato simples, em quatro repetições. O maior ganho em altura (12,52cm foi obtido com as doses de 97,58kg ha-1 de N, enquanto o maior incremento no diâmetro do colo (2,18mm foi obtido com as doses de 150kg ha-1 de N e 150kg ha-1 de P2O5. O maior número de folhas foi observado na presença de 126,03kg ha-1 de N e 150kg ha-1 de P2O5. A maior produção de massa seca da parte aérea total foi constatada na dose de 98,71kg ha-1 de N e 150kg ha-1 de P2O5. A área foliar cresceu linearmente para ambos fatores As adubações estudadas contribuem de forma positiva para a formação de mudas de umbuzeiro, podendo antecipar a formação de porta-enxertos para algumas fruteiras do gênero Spondias. Doses de fósforo a partir de 150kg ha-1 não são recomendadas quando se pretende produzir picles, a partir do xilopódio do umbuzeiro.The fertilization, notable with nitrogen and phosphorous, is fundamental on initial development stadium on fruits nursery trees. However, there is little scientific information about ‘umbuzeiro’. This work had as objective to evaluate the effect of nitrogen and phosphorous’ doses on ‘umbuzeiro’ rootstocks (Spondias tuberosa Arr. Câm.. The experiment was carried out under nursery at ‘Universidade Federal de Sergipe’ being used experimental design of randomized blocks in factorial

  6. Doses of controlled-release fertilizer for production of rubber tree rootstocks

    Directory of Open Access Journals (Sweden)

    Renato Luis Grisi Macedo

    2012-06-01

    Full Text Available This experimental study aimed to evaluate the effects of doses of controlled-release fertilizer (ALL on the development of rubber tree rootstocks. The fertilizer used was Osmocote®, scheduled to be released for 8-9 months and with the following composition: N (15%, P2O5 (9%, K2O (12%, Mg (1%, S (2.3%, B (0.02%, Cu (0.05%, Fe (1%, Mn (0.06%, Mo (0.02% and Zn (0.05%. A randomized block design was used, with four treatments and eight replicates of 20 plants per plot. The controlled-release fertilizer was added to Rendimax Floreira® substrate at doses of 0, 3, 6 and 9 g per liter, and rootstocks were produced in plastic containers with a capacity of two liters of substrate. Three seeds of clone GT 1 were scattered in each container and thinning was performed on day 60, leaving the most vigorous plant only. After the fourth leaf shot from each rootstock, the containers of each treatment were topped, due to compaction, with 300 mL of the relevant fertilizer and substrate mixture. The rootstocks were evaluated at eight months of age as to height, stem diameter (DC 5 cm above root collar, total dry matter, shoot and root dry matter, leaf nutrient levels and percentage of plants suitable for grafting (DC≥1.0 cm. Results revealed that adequate development and nutrition of rootstocks was achieved by using 6 g of controlled-release fertilizer per liter of substrate.

  7. Secretory Cavity Development and Its Relationship with the Accumulation of Essential Oil in Fruits of Citrus medica L. var. sarcodactylis (Noot.) Swingle

    Institute of Scientific and Technical Information of China (English)

    She-Jian Liang; Hong Wu; Xuan Lun; Dong-Wen Lu

    2006-01-01

    The developmental types of secretory cavities in Citrus remain controversial. The relationship between secretory cavity development and the accumulation of essential oil in fruits of Citrus species is also unknown. In order to develop better insights into these problems, histological, histochemical, and cytochemical methods were used to investigate secretory cavity development and the accumulation of essential oil at different developmental stages of fruits of Citrus medica L. var. sarcodactylis (Noot.) Swingle.The results indicate that the secretory cavity of the variety seemed to originate from an epidermal cell and a subepidermal cell. These two cells underwent successive divisions, resulting in the formation of two parts: (i) a conical cap; and (ii) a globular gland. The formation of the lumen was schizolysigenous. Regular changes in the size of vacuoles and the accumulation of essential oil were revealed during the process of secretory cavity development. In addition, when fruits were a light yellow or golden color, the structure of secretory cavities was well developed and the content of essential oil in a single fruit reached a maximum. It would be most appropriate to collect the fruit as a medicinal material at this time.

  8. Mini Review: Innovation technology cultivaion of Citrus Tangerines Borneo Prima in East Kalimantan

    Directory of Open Access Journals (Sweden)

    AFRILIA TRI WIDYAWATI

    2017-03-01

    Full Text Available Abstract. Widyawati AT, Nurbani. 2017. Mini Review: Innovation technology cultivaion of Citrus Tangerines Borneo Prima in East Kalimantan. Pros Sem Nas Masy Biodiv Indon 3: 127-131. The demand for high-value commodities such as oranges continues to increase every year. One of the qualities of orange that can not be met by domestic manufacturers is the color of a citrus peel. Most consumers like citrus orange, like mandarin oranges and other citrus imports. Efforts to reduce the national citrus imports is to improve the productivity and quality of citrus orange in Indonesia. Citrus Tangerines Borneo Prima is one of the featured horticultural commodities in East Kalimantan, which has the advantage of being low lying tangerine with orange rind. It Is indispensable citrus cultivation technique is good and right, so that the citrus plant can develop optimally so that later can produce citrus fruit both in quality and quantity.

  9. Genome-wide identification of sweet orange (Citrus sinensis histone modification gene families and their expression analysis during the fruit development and fruit-blue mold infection process

    Directory of Open Access Journals (Sweden)

    Jidi eXu

    2015-08-01

    Full Text Available In eukaryotes, histone acetylation and methylation have been known to be involved in regulating diverse developmental processes and plant defense. These histone modification events are controlled by a series of histone modification gene families. To date, there is no study regarding genome-wide characterization of histone modification related genes in citrus species. Based on the two recent sequenced sweet orange genome databases, a total of 136 CsHMs (Citrus sinensis histone modification genes, including 47 CsHMTs (histone methyltransferase genes, 23 CsHDMs (histone demethylase genes, 50 CsHATs (histone acetyltransferase genes, and 16 CsHDACs (histone deacetylase genes were identified. These genes were categorized to 11 gene families. A comprehensive analysis of these 11 gene families was performed with chromosome locations, phylogenetic comparison, gene structures and conserved domain compositions of proteins. In order to gain an insight into the potential roles of these genes in citrus fruit development, 42 CsHMs with high mRNA abundance in fruit tissues were selected to further analyze their expression profiles at six stages of fruit development. Interestingly, a numbers of genes were expressed highly in flesh of ripening fruit and some of them showed the increasing expression levels along with the fruit development. Furthermore, we analyzed the expression patterns of all 136 CsHMs response to the infection of blue mold (Penicillium digitatum, which is the most devastating pathogen in citrus postharvest process. The results indicated that 20 of them showed the strong alterations of their expression levels during the fruit-pathogen infection. In conclusion, this study presents a comprehensive analysis of the histone modification gene families in sweet orange and further elucidates their behaviors during the fruit development and the blue mold infection responses.

  10. Genome-wide identification of sweet orange (Citrus sinensis) histone modification gene families and their expression analysis during the fruit development and fruit-blue mold infection process.

    Science.gov (United States)

    Xu, Jidi; Xu, Haidan; Liu, Yuanlong; Wang, Xia; Xu, Qiang; Deng, Xiuxin

    2015-01-01

    In eukaryotes, histone acetylation and methylation have been known to be involved in regulating diverse developmental processes and plant defense. These histone modification events are controlled by a series of histone modification gene families. To date, there is no study regarding genome-wide characterization of histone modification related genes in citrus species. Based on the two recent sequenced sweet orange genome databases, a total of 136 CsHMs (Citrus sinensis histone modification genes), including 47 CsHMTs (histone methyltransferase genes), 23 CsHDMs (histone demethylase genes), 50 CsHATs (histone acetyltransferase genes), and 16 CsHDACs (histone deacetylase genes) were identified. These genes were categorized to 11 gene families. A comprehensive analysis of these 11 gene families was performed with chromosome locations, phylogenetic comparison, gene structures, and conserved domain compositions of proteins. In order to gain an insight into the potential roles of these genes in citrus fruit development, 42 CsHMs with high mRNA abundance in fruit tissues were selected to further analyze their expression profiles at six stages of fruit development. Interestingly, a numbers of genes were expressed highly in flesh of ripening fruit and some of them showed the increasing expression levels along with the fruit development. Furthermore, we analyzed the expression patterns of all 136 CsHMs response to the infection of blue mold (Penicillium digitatum), which is the most devastating pathogen in citrus post-harvest process. The results indicated that 20 of them showed the strong alterations of their expression levels during the fruit-pathogen infection. In conclusion, this study presents a comprehensive analysis of the histone modification gene families in sweet orange and further elucidates their behaviors during the fruit development and the blue mold infection responses.

  11. Effect of rootstock diameter on apple saplings growth

    Directory of Open Access Journals (Sweden)

    VAHID AVDIU

    2014-03-01

    Full Text Available This research paper presents the results of a field trial with managed nursery trees including two apple cultivars Golden Reinders and Gala Galaxy on the rootstocks M9 and MM 106. In April 2011, the saplings (bench grafted in March 2011 were planted in the distance 100 cm x 35 cm in randomized block design in threecombinations of rootstock diameters (5-7 mm, 7-9 mm, 9-11 mm with threereplications (in total 60 saplings for each apple cultivar-rootstock and combinations in Mirovica, Kosovo. The following parameters were examined: growth, rootstock diameter, scion diameter, and stocks growth dynamic. The experimental design was a ANOVAs one-way analysing two different factors cultivars, rootstocks types and treatments (three combinations of rootstocks diameter. Significant differences were found in scion thickness and sapling growth among the three different combinations of rootstock diameter, dimensions and cultivars. Insignificant were differences were found within factors as cultivar, rootstock and their combinations Key words: Amino acids, Moringa oleifera, poultry manure.

  12. Scion-rootstocks relationships and root behaviour in glasshouse roses.

    NARCIS (Netherlands)

    Fuchs, H.W.M.

    1994-01-01

    In the Netherlands, the cultivation of cut roses in the glasshouse is commonly carried out yearround. Most cultivars are grown on a rootstock. The first part of this study investigates various rootstocks for their ability to influence production and quality throughout the year. The mutual influence

  13. PRODUÇÃO E DESENVOLVIMENTO DA TANGERINEIRA-'MONTENEGRINA' PROPAGADA POR ENXERTIA E ESTAQUIA, NO RIO GRANDE DO SUL MANDARIN CV. 'MONTENEGRINA' PRODUCTION AND DEVELOPMENT PROPAGATED BY CUTTINGS AND GRAFTING IN RIO GRANDE DO SUL STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    GILMAR SCHÄFER

    2001-12-01

    Full Text Available A tangerineira-'Montenegrina' (Citrus deliciosa Ten., devido às boas características de sabor, conservação e colheita tardia dos frutos, é muito apreciada e cultivada no Rio Grande do Sul. Os pomares comerciais são praticamente formados por mudas enxertadas sobre Poncirus trifoliata (L. Raf. Devido à escassez de informações relativas à combinação desta cultivar com outros porta-enxertos, bem como sua propagação por estaquia, esta pesquisa objetivou estudar o comportamento inicial de plantas enxertadas sobre citrange 'Troyer' (Citrus sinensis (L. Osb. x P. trifoliata, citrumelo 'Swingle' (C. paradisi Macf. x P. trifoliata e P. trifoliata e de plantas propagadas por estaquia. O experimento foi instalado na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul - UFRGS, em junho de 1989, delineado em blocos casualisados, com cinco plantas úteis por parcela e quatro repetições. Os resultados compreenderam as primeiras safras ocorridas de 1993 a 1998. O citrumeleiro 'Swingle' foi o porta-enxerto que melhores resultados apresentou, aumentando a eficiência produtiva da tangerineira-'Montenegrina', cultivada na Depressão Central do Rio Grande do Sul, sendo que o Poncirus trifoliata diminuiu o desenvolvimento vegetativo das copas e induziu baixa eficiência produtiva. A propagação por estaquia não ofereceu vantagens em relação à enxertia sobre citrumeleiro 'Swingle' e citrangeiro 'Troyer'.The mandarin 'Montenegrina' (Citrus deliciosa Ten. yield from plants propagated either by grafting or cutting was evaluated at the 'Universidade Federal do Rio Grande do Sul' experimental agronomic station, southern Brazil, from 1993 to 1998. Three rootstocks were used in the grafted plants. The rootstocks studied were: 'Swingle' citrumelo [Citrus paradisi Macf. x Poncirus trifoliata (L. Raf.] 'Troyer' citrange (Citrus sinensis x P. trifoliata and trifoliate orange (P. trifoliata. The work was done using a randomized

  14. 不同pH值下接种AM真菌对枳橙苗生长及光合作用的影响%Effects of AM Fungi on Growth and Photosynthesis of Citrus Rootstock Seedlings in Soils with Different pH

    Institute of Scientific and Technical Information of China (English)

    牛琳琳; 高崇; 曾明; 李伟; 雷世梅; 伍加勇

    2012-01-01

    以枳橙Citrus sinensis×Poncirus tri foliata为试材,研究不同pH值(5.5~6.5,6.5~7.5,7.5~8.5)条件下接种丛枝菌根(AM)真菌摩西球囊霉Glomus mosseae对枳橙苗生长及光合能力的影响.结果表明,不同pH值水平下接种摩西球囊霉均能有效地侵染枳橙植株,菌根侵染率在65%以上;接种处理植株的菌根侵染率、株高、生物量干重、叶片叶绿素含量、光合作用速率和蒸腾速率等指标均显著高于不接种植株;接种AM真菌增强了宿主植物对碱性土的适应性.%Citrange seedlings (Citrus sinensis (L. ) Osbeck×Poncirus trifoliata (L. )) were used to study the effect of arbuscular mycorrhizal (AM) fungus (Glomus mossease) on growth and photo-. synthesis of the trees under different pH conditions (pH 5. 5~6. 5, 6. 5~7. 5, 7. 5~8. 5). Results indicated that the mycorrhizal fungus Glomus mossease was equally effective in infecting plants under all tested pH conditions and the infection rates were higher than 65%. Mycorrhiza infection rate, plant height, dry weight, chlorophyll content, photosynthetic activity and transpiration rate of inoculated plants were significantly higher than those of control plants. Inoculation with AM fungi enhanced the adaptability of the host plants to alkaline soils.

  15. Deep sequencing discovery of novel and conserved microRNAs in trifoliate orange (Citrus trifoliata

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    Yu Huaping

    2010-07-01

    Full Text Available Abstract Background MicroRNAs (miRNAs play a critical role in post-transcriptional gene regulation and have been shown to control many genes involved in various biological and metabolic processes. There have been extensive studies to discover miRNAs and analyze their functions in model plant species, such as Arabidopsis and rice. Deep sequencing technologies have facilitated identification of species-specific or lowly expressed as well as conserved or highly expressed miRNAs in plants. Results In this research, we used Solexa sequencing to discover new microRNAs in trifoliate orange (Citrus trifoliata which is an important rootstock of citrus. A total of 13,106,753 reads representing 4,876,395 distinct sequences were obtained from a short RNA library generated from small RNA extracted from C. trifoliata flower and fruit tissues. Based on sequence similarity and hairpin structure prediction, we found that 156,639 reads representing 63 sequences from 42 highly conserved miRNA families, have perfect matches to known miRNAs. We also identified 10 novel miRNA candidates whose precursors were all potentially generated from citrus ESTs. In addition, five miRNA* sequences were also sequenced. These sequences had not been earlier described in other plant species and accumulation of the 10 novel miRNAs were confirmed by qRT-PCR analysis. Potential target genes were predicted for most conserved and novel miRNAs. Moreover, four target genes including one encoding IRX12 copper ion binding/oxidoreductase and three genes encoding NB-LRR disease resistance protein have been experimentally verified by detection of the miRNA-mediated mRNA cleavage in C. trifoliata. Conclusion Deep sequencing of short RNAs from C. trifoliata flowers and fruits identified 10 new potential miRNAs and 42 highly conserved miRNA families, indicating that specific miRNAs exist in C. trifoliata. These results show that regulatory miRNAs exist in agronomically important trifoliate orange

  16. Secondary product glucosyltransferase and putative glucosyltransferase expression during Citrus paradisi (c.v. Duncan) growth and development.

    Science.gov (United States)

    Daniel, Jala J; Owens, Daniel K; McIntosh, Cecilia A

    2011-10-01

    Flavonoids are secondary metabolites that have significant roles in plant defense and human nutrition. Glucosyltransferases (GTs) catalyze the transfer of sugars from high energy sugar donors to other substrates. Several different secondary product GTs exist in the tissues of grapefruit making it a model plant for studying their structure and function. The goal of this investigation was to determine the expression patterns of seven putative secondary product GTs during grapefruit growth and development by quantifying mRNA expression levels in the roots, stems, leaves, flowers, and mature fruit to establish whether the genes are expressed constitutively or if one or more could be expressed in a tissue specific manner and/or developmentally regulated. Six growth stages were defined from which RNA was extracted, and expression levels were quantified by standardized densitometry of gene-specific RT-PCR products. Results show that there were variable degrees of PGT expression in different tissues and at different developmental stages. These results add to the growing knowledge base of dynamics of expression and potential regulation of secondary metabolism in Citrus paradisi.

  17. Developing and demonstrating low-energy climate control and production techniques for greenhouse-grown citrus and ornamental crops

    Energy Technology Data Exchange (ETDEWEB)

    Bodnaruk, W.H. Jr.

    1983-04-01

    The aim of this study was to develop and demonstrate low energy climate control and production techniques for greenhouse grown citrus and ornamental crops. Emphasis was placed on design, fuel efficiency and plant response to warm water soil heating systems using solar energy and LP gas. An energy requirement of 28Btus output per hour per square foot of bed space will provide soil temperature of 70/sup 0/F minimum when air temperatures are maintained at 60/sup 0/F. Soil heating to 70/sup 0/ increased rooting and growth of 8 foliage plant varieties by 25 to 45% compared to plants grown under 60/sup 0/F air temperature conditions. Providing soil heating, however, increased fuel consumption in the central Florida test facilities by 30% in the winters of 1980-81 and 1981-82. Solar tie-in to soil heating systems has the potential of reducing fuel usage. Solar heated water provided 4 hours of soil heating following a good collection day. Decreased in-bed pipe spacing and increased storage capacity should increase the solar percentage to 6 hours.

  18. Genetic Transformation in Citrus

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    Dicle Donmez

    2013-01-01

    Full Text Available Citrus is one of the world’s important fruit crops. Recently, citrus molecular genetics and biotechnology work have been accelerated in the world. Genetic transformation, a biotechnological tool, allows the release of improved cultivars with desirable characteristics in a shorter period of time and therefore may be useful in citrus breeding programs. Citrus transformation has now been achieved in a number of laboratories by various methods. Agrobacterium tumefaciens is used mainly in citrus transformation studies. Particle bombardment, electroporation, A. rhizogenes, and a new method called RNA interference are used in citrus transformation studies in addition to A. tumefaciens. In this review, we illustrate how different gene transformation methods can be employed in different citrus species.

  19. Citrus breeding, genetics and genomics in Japan.

    Science.gov (United States)

    Omura, Mitsuo; Shimada, Takehiko

    2016-01-01

    Citrus is one of the most cultivated fruits in the world, and satsuma mandarin (Citrus unshiu Marc.) is a major cultivated citrus in Japan. Many excellent cultivars derived from satsuma mandarin have been released through the improvement of mandarins using a conventional breeding method. The citrus breeding program is a lengthy process owing to the long juvenility, and it is predicted that marker-assisted selection (MAS) will overcome the obstacle and improve the efficiency of conventional breeding methods. To promote citrus molecular breeding in Japan, a genetic mapping was initiated in 1987, and the experimental tools and resources necessary for citrus functional genomics have been developed in relation to the physiological analysis of satsuma mandarin. In this paper, we review the progress of citrus breeding and genome researches in Japan and report the studies on genetic mapping, expression sequence tag cataloguing, and molecular characterization of breeding characteristics, mainly in terms of the metabolism of bio-functional substances as well as factors relating to, for example, fruit quality, disease resistance, polyembryony, and flowering.

  20. Signaling pathways in a Citrus EST database

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    Angela Mehta

    2007-01-01

    Full Text Available Citrus spp. are economically important crops, which in Brazil are grown mainly in the State of São Paulo. Citrus cultures are attacked by several pathogens, causing severe yield losses. In order to better understand this culture, the Millenium Project (IAC Cordeirópolis was launched in order to sequence Citrus ESTs (expressed sequence tags from different tissues, including leaf, bark, fruit, root and flower. Plants were submitted to biotic and abiotic stresses and investigated under different development stages (adult vs. juvenile. Several cDNA libraries were constructed and the sequences obtained formed the Citrus ESTs database with almost 200,000 sequences. Searches were performed in the Citrus database to investigate the presence of different signaling pathway components. Several of the genes involved in the signaling of sugar, calcium, cytokinin, plant hormones, inositol phosphate, MAPKinase and COP9 were found in the citrus genome and are discussed in this paper. The results obtained may indicate that similar mechanisms described in other plants, such as Arabidopsis, occur in citrus. Further experimental studies must be conducted in order to understand the different signaling pathways present.

  1. Utilizing Citrullus lanatus var. citroides germplasm for developing tetraploid lines useful as rootstocks and in breeding programs of seedless watermelon lines

    Science.gov (United States)

    In recent years, soil-borne diseases and pests have intensified in watermelon, particularly after the phasing out of the soil fumigant methyl bromide, and there is a continuous need to develop solutions for reducing the disease and pest pressure in this important cucurbit crop. Grafting of watermel...

  2. Resistance of Some Vitis Rootstocks to Xiphinema index.

    Science.gov (United States)

    Harris, A R

    1983-07-01

    Thirty-eight grapevine (Vitis spp.) rootstocks were screened in pots for resistance to the dagger nematode, Xiphinema index, from 1979 to 1981. Resistance ratings were based on visible root symptoms and on changes in the nematode populations over 16 months. Nineteen of the 23 Californian hybrid rootstocks tested were resistant, as were 'Harmony',' 'Freedom,' 'Schwarzmann,' and '3309.' Two hybrids of V. rufotomentosa, '171-52' and '176-9,' were possibly immune to X. index. The rootstocks 'ARG 1,' ' 110 R,' '1202,' and '1616,' which are used commercially for phylloxera resistance were susceptible.

  3. Quince 'CPP': new dwarf rootstock for pear trees on organic and high density planting

    OpenAIRE

    Renato Vasconcelos Botelho; Everton Schneider; Danielle Machado; Rafael Piva; Andricia Verlindo

    2012-01-01

    In Brazil, pear production presents the same incipient situation over the last 15 years, due mostly to low production technology. In this context, this study aimed to evaluate the development, growth and production of the pear tree cultivars Cascatense, Tenra and Hosui grafted on 'CPP' quince rootstock, using 'FT' pear as interstem. This trial was carried out in Guarapuava, State of Paraná, Southern region of Brazil, by five productive cycles. The pear trees were planted in September of 2004,...

  4. Prunus hybrids rootstocks for flat peach

    Directory of Open Access Journals (Sweden)

    Pilar Legua

    2012-02-01

    Full Text Available Peach (Prunus persica L. is the most important stone fruit tree grown in Spain and is the second most important fruit crop in Europe. The influence of eight Prunus rootstocks (GF-677, Krymsk® 86, PADAC 97-36, PADAC 99-05, PADAC 9912-03, PADAC 0024-01, PAC 0021-01 and PAC 0022-01 on vigor, yield and fruit quality traits of 'UFO 3' flat peach cultivar was studied. The highest trunk cross sectional area was exhibited by GF-677 and the lowest by PADAC 99-05, while intermediate values were found on the other rootstocks. The highest yield efficiency was found on PADAC 99-05, PAC 0021-01, PAC 0022-01 and PADAC 0024-01 and the lowest was shown on Krymsk® 86. The fruit quality parameters measured were color, fruit and stone weights, equatorial diameter, pulp thickness, pulp yield, firmness, pH, soluble solids content and titratable acidity. 'UFO 3' grafted on GF-677 resulted in the largest fruit weight, while the smallest was on PADAC 99-05. Fruits of 'UFO 3' showed a tendency to have higher firmness, higher red colored skin and RI when grafted on PADAC 99-05.

  5. Improving agronomic water use efficiency in tomato by rootstock-mediated hormonal regulation of leaf biomass.

    Science.gov (United States)

    Cantero-Navarro, Elena; Romero-Aranda, Remedios; Fernández-Muñoz, Rafael; Martínez-Andújar, Cristina; Pérez-Alfocea, Francisco; Albacete, Alfonso

    2016-10-01

    Water availability is the most important factor limiting food production, thus developing new scientific strategies to allow crops to more efficiently use water could be crucial in a world with a growing population. Tomato is a highly water consuming crop and improving its water use efficiency (WUE) implies positive economic and environmental effects. This work aimed to study and exploit root-derived hormonal traits to improve WUE in tomato by grafting on selected rootstocks. Firstly, root-related hormonal parameters associated to WUE were identified in a population of recombinant inbred lines (RILs) derived from the wild tomato species Solanum pimpinellifolium. A principal component analysis (PCA) revealed that some hormonal traits were associated with productivity (plant biomass and photosynthesis) and WUE in the RIL population. Leaf ABA concentration was associated to the first component (PC1) of the PCA, which explained a 60% of the variance in WUE, while the ethylene precursor ACC and the ratio ACC/ABA were also associated to PC1 but in the opposite direction. Secondly, we selected RILs according to their extreme biomass (high, B, low, b) and water use (high, W, low, w), and studied the differential effect of shoot and root on WUE by reciprocal grafting. In absence of any imposed stress, there were no rootstock effects on vegetative shoot growth and water relations. Finally, we exploited the previously identified root-related hormonal traits by grafting a commercial tomato variety onto the selected RILs to improve WUE. Interestingly, rootstocks that induced low biomass and water use, 'bw', improved fruit yield and WUE (defined as fruit yield/water use) by up to 40% compared to self-grafted plants. Although other hormonal factors appear implicated in this response, xylem ACC concentration seems an important root-derived trait that inhibits leaf growth but does not limit fruit yield. Thus tomato WUE can be improved exploiting rootstock-derived hormonal signals

  6. Rootstock effects on gene expression patterns in apple tree scions.

    Science.gov (United States)

    Jensen, Philip J; Rytter, Jo; Detwiler, Elizabeth A; Travis, James W; McNellis, Timothy W

    2003-11-01

    Like many fruit trees, apple trees (Malus pumila) do not reproduce true-to-type from seed. Desirable cultivars are clonally propagated by grafting onto rootstocks that can alter the characteristics of the scion. For example, the M.7 EMLA rootstock is semi-dwarfing and reduces the susceptibility of the scion to Erwinia amylovora, the causal agent of fire blight disease. In contrast, the M.9 T337 rootstock is dwarfing and does not alter fire blight susceptibility of the scion. This study represents a comprehensive comparison of gene expression patterns in scions of the 'Gala' apple cultivar grafted to either M.7 EMLA or M.9 T337. Expression was determined by cDNA-AFLP coupled with silver staining of the gels. Scions grafted to the M.9 T337 rootstock showed higher expression of a number of photosynthesis-related, transcription/translation-related, and cell division-related genes, while scions grafted to the M.7 EMLA rootstock showed increased stress-related gene expression. The observed differences in gene expression showed a remarkable correlation with physiological differences between the two graft combinations. The roles that the differentially expressed genes might play in tree stature, stress tolerance, photosynthetic activity, fire blight resistance, and other differences conferred by the two rootstocks are discussed.

  7. [Salt stress tolerance of cucumber-grafted rootstocks].

    Science.gov (United States)

    Wang, Li-Ping; Sun, Jin; Guo, Shi-Rong; Liu, Shu-Ren; Liu, Chao-Jie; Tian, Jing

    2012-05-01

    Taking 4 different Cucurbita maxima x C. moschata rootstocks for cucumber (Cucumis sativus) as test materials, a solution culture experiment was conducted to study their growth and antioxidative enzyme activities under the stresses of Ca(NO3)2 and NaCl, with the salt stress tolerance of the rootstocks evaluated by subordinate function. At 30 mmol x L(-1) of Ca (NO3)2 or 45 mmol x L(-1) of NaCl, the growth of the rootstock seedlings was improved; but at 60 and 120 mmol x L(-1) of Ca(NO3)2 or 90 and 180 mmol x L(-1) of NaCl, the growth and the antioxidative systems of the seedlings were inhibited, and the salt injury index of 'Qingzhen No. 1' was the smallest, with the decrement of biomass and SOD, POD and CAT activities and the increment of relative conductance being significantly lower than those of the others. Under the stress of high concentration Ca(NO3)2, the SOD, POD and CAT activities of test rootstocks were higher, and the salt injury index and relative conductance were lower, as compared with those under high concentration NaCl, suggesting that the damage of Ca(NO3)2 stress to cucumber-grafted rootstock were smaller than that of NaCl stress. Among the 4 rootstocks, 'Qingzhen No. 1' had the strongest salt stress tolerance, followed by 'Zuomu Nangua', 'Fengyuan Tiejia', and 'Chaoba Nangua'.

  8. Simple sequence repeat-based assessment of genetic relationships among Prunus rootstocks.

    Science.gov (United States)

    Turkoglu, Z; Bilgener, S; Ercisli, S; Bakir, M; Koc, A; Akbulut, M; Gercekcioglu, R; Gunes, M; Esitken, A

    2010-11-03

    Ten SSR loci, previously developed for Prunus, were analyzed to examine genetic relationships among 23 rootstock candidates for sweet and sour cherries, of the species P. avium, P. cerasus, P. mahaleb, and P. angustifolia. Five genotypes of P. laurocerasus, not used as rootstock, were included in the molecular analysis. The number of alleles per locus ranged from 8 to 12, with a mean of 9, while the number of microsatellite genotypes varied from 8 to 17, indicating that the SSRs were highly informative. The degree of heterozygosity (0.61) was high. Clustering analysis resulted in two main clusters. The first cluster was divided into two subclusters; the first subcluster consisted of P. avium and P. cerasus, and the second subcluster consisted of P. laurocerasus. The second cluster was divided into two subclusters. The first subcluster consisted of P. mahaleb genotypes and the second consisted of P. angustifolia genotypes. The reference rootstocks also clustered with their associated botanical species. Unweighted pair-group method with arithmetic mean analysis demonstrated that P. laurocerasus genotypes had less genetic variation and that P. avium genotypes were more closely related to P. cerasus. The SSR-based phylogeny was generally consistent with Prunus taxonomy information, suggesting the applicability of SSR analysis for genotyping and phylogenetic studies in the genus Prunus.

  9. Salt tolerance of precocious-dwarf cashew rootstocks: physiological and growth indexes

    Directory of Open Access Journals (Sweden)

    Carneiro Paulo Torres

    2004-01-01

    Full Text Available The cashew crop (Anacardium occiedentale L. is of great economic and social importance for Northeast Brazil, a region usually affected by water and soil salinity. The present study was conducted in a greenhouse to evaluate the effects of four salinity levels established through electrical conductivity of irrigation water (ECw: 0.7, 1.4, 2.1 and 2.8 dS m-1, at 25ºC, on growth and physiological indexes of five rootstocks of dwarf-precocious cashew varieties CCP06, CCP09, CCP1001, EMBRAPA50, and EMBRAPA51. Plant height, leaf area, dry weight of root, shoot and total; water content of leaves, root/shoot ratio, leaf area ratio, absolute and relative growth rates and rate of net assimilation were evaluated. The majority of the evaluated variables were found to be affected by ECw and the effects varied among clones; however, no significant interactive effects were observed for factors. The value of ECw = 1.39 dS m-1 was considered as a threshold tolerance for the precocious cashew rootstocks used in this study. The dwarf-precocious cashew is moderately sensible to soil salinity during the formation phase of rootstock. Clones EMBRAPA51 and EMBRAPA50 presented, respectively, the least and the best development indexes.

  10. Is rootstock-induced dwarfing in olive an effect of reduced plant hydraulic efficiency?

    Science.gov (United States)

    Nardini, Andrea; Gascó, Antonio; Raimondo, Fabio; Gortan, Emmanuelle; Lo Gullo, Maria A; Caruso, Tiziano; Salleo, Sebastiano

    2006-09-01

    We investigated the hydraulic architecture of young olive trees either self-rooted or grafted on rootstocks with contrasting size-controlling potential. Clones of Olea europea L. (Olive) cv 'Leccino' inducing vigorous scion growth (Leccino 'Minerva', LM) or scion dwarfing (Leccino 'Dwarf', LD) were studied in different scion/rootstock combinations (LD, LM, LD/LD, LM/LM, LD/LM and LM/LD). Shoots growing on LD root systems developed about 50% less leaf surface area than shoots growing on LM root systems. Root systems accounted for 60-70% of plant hydraulic resistance (R), whereas hydraulic resistance of the graft union was negligible. Hydraulic conductance (K = 1/R) of LD root systems was up to 2.5 times less than that of LM root systems. Total leaf surface area (A(L)) was closely and positively related to root hydraulic conductance so that whole-plant hydraulic conductance scaled by A(L) did not differ between experimental groups. Accordingly, maximum transpiration rate and minimum leaf water potential did not differ significantly among experimental groups. We conclude that reduced root hydraulic conductance may explain rootstock-induced dwarfing in olive.

  11. The aconitate hydratase family from Citrus

    Directory of Open Access Journals (Sweden)

    Cercos Manuel

    2010-10-01

    Full Text Available Abstract Background Research on citrus fruit ripening has received considerable attention because of the importance of citrus fruits for the human diet. Organic acids are among the main determinants of taste and organoleptic quality of fruits and hence the control of fruit acidity loss has a strong economical relevance. In citrus, organic acids accumulate in the juice sac cells of developing fruits and are catabolized thereafter during ripening. Aconitase, that transforms citrate to isocitrate, is the first step of citric acid catabolism and a major component of the citrate utilization machinery. In this work, the citrus aconitase gene family was first characterized and a phylogenetic analysis was then carried out in order to understand the evolutionary history of this family in plants. Gene expression analyses of the citrus aconitase family were subsequently performed in several acidic and acidless genotypes to elucidate their involvement in acid homeostasis. Results Analysis of 460,000 citrus ESTs, followed by sequencing of complete cDNA clones, identified in citrus 3 transcription units coding for putatively active aconitate hydratase proteins, named as CcAco1, CcAco2 and CcAco3. A phylogenetic study carried on the Aco family in 14 plant species, shows the presence of 5 Aco subfamilies, and that the ancestor of monocot and dicot species shared at least one Aco gene. Real-time RT-PCR expression analyses of the three aconitase citrus genes were performed in pulp tissues along fruit development in acidic and acidless citrus varieties such as mandarins, oranges and lemons. While CcAco3 expression was always low, CcAco1 and CcAco2 genes were generally induced during the rapid phase of fruit growth along with the maximum in acidity and the beginning of the acid reduction. Two exceptions to this general pattern were found: 1 Clemenules mandarin failed inducing CcAco2 although acid levels were rapidly reduced; and 2 the acidless "Sucreña" orange

  12. PHYSICO-CHEMICAL CHARACTERIZATION AND PRODUCT DEVELOPMENT FROM LOCAL CITRUS GERMPLASMS AVAILABLE IN THE SOUTH WESTERN REGION OF BANGLADESH

    Directory of Open Access Journals (Sweden)

    M. S. Akhter

    2013-10-01

    Full Text Available The experiment was carried out to study the physico-chemical characteristics of 20 selected citrus fruits germplasm of South Western region of Bangladesh during July 2010 to January 2012. There was significant variation among the germplasms in relation to fruit characteristics and organolaptic evaluation. Better performance was found in germplasm No. 20 in respect of total fruit weight, weight of seed and skin thickness of fruits. Germplasm No.1 showed better performance in respect of percentage of edible portion and germplasm No. 6 in respect of percentage of non edible portion. The total soluble solids found higher in germplasm No. 20 (12.23 % and titratable acidity in germplasm No. 16 (49.33 %. Vitamin C and carotenoids found maximum in germplasm No. 20 (442.70 mg/100g. Germplasm No. 4 and 12 was better in respect of anthocyanin (0.10 mg/100gm and flavonoids (0.19 gm content of fruit pulp. Considering desired fruit characteristics germplasam No. 20 (pummelo was found better. Citrus fruits' squash was successfully prepared by using 60 g sugar containing treatment consisting 50-80 g of sugar with 10 g variation of sugar in three treatments without changing other ingredient. Citrus fruits jelly was successfully prepared by using 300 g sugar containing treatment consisting 250-350 g of sugar with 50 g variation of sugar in three treatments without changing other ingredient. Citrus fruits jarok was successfully prepared by using 55 g salt containing treatment consisting 50-60 g of salt with 5 g variation of salt in three treatments without changing other ingredient.

  13. Crescimento vegetativo de plantas cítricas no norte e noroeste do Paraná Vegetative growth of citrus trees in north an northwest of Parana

    Directory of Open Access Journals (Sweden)

    Neusa Maria Colauto Stenzel

    2005-12-01

    Full Text Available Este trabalho avaliou, em Paranavaí e Londrina-PR, os fluxos de crescimento vegetativo dos ramos de laranjeira 'Folha Murcha' enxertada sobre limoeiro 'Cravo' (Citrus limonia Osb., limoeiro 'Volcameriano' (Citrus volkameriana Ten. e Pasq., tangerineira 'Sunki' (Citrus sunki Hort. ex Tan., tangerineira 'Cleópatra' (Citrus reshni Hort. ex Tan. e laranjeira 'Pêra' sobre o porta-enxerto limoeiro 'Cravo'. Ocorreram seis fluxos de crescimento em Paranavaí e sete em Londrina, no inverno, primavera, verão e outono, para todas as combinações de copa/porta-enxerto. O comprimento final dos ramos (121,2 mm a 151,6 mm não foi influenciado pelas combinações copa/porta-enxerto em Londrina, mas em Paranavaí a combinação 'Pêra'/limoeiro 'Cravo' produziu ramos mais longos que as demais. O período de crescimento dos ramos variou de 25,5 a 37,8 dias e foi menor em Paranavaí do que em Londrina, para todas as combinações de copa/porta-enxerto. Os resultados são discutidos em relação às características edafoclimáticas dos dois locais.This work evaluated in Paranavaí and Londrina, PR, Brazil, the vegetative growth fluxes of branches of 'Folha Murcha' orange on 'Rangpur' lime (Citrus limonia Osb., 'Volkamer' lemon (Citrus volkameriana Ten. & Pasq., 'Sunki' mandarin (Citrus sunki Hort. ex Tan., 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan., and 'Pêra' orange on 'Rangpur' lime rootstock. Six growth flushes were observed in Paranavaí, and seven were observed in Londrina, in winter, spring, summer, and autumn, for all scion/rootstock combinations. The final length of the branches (121.2 mm to 151.6 mm was not influenced by the scion/rootstock combinations in Londrina; in Paranavaí, however, the 'Pêra'/'Rangpur' lime combination produced longer branches than the others. The growth period of branches ranged from 25.5 to 37.8 days and was shorter in Paranavaí than in Londrina, for all scion/rootstock combinations. The results are discussed

  14. Asian Citrus Psyllid Expression Profiles Suggest Candidatus Liberibacter Asiaticus-Mediated Alteration of Adult Nutrition and Metabolism, and of Nymphal Development and Immunity.

    Science.gov (United States)

    Vyas, Meenal; Fisher, Tonja W; He, Ruifeng; Nelson, William; Yin, Guohua; Cicero, Joseph M; Willer, Mark; Kim, Ryan; Kramer, Robin; May, Greg A; Crow, John A; Soderlund, Carol A; Gang, David R; Brown, Judith K

    2015-01-01

    The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is the insect vector of the fastidious bacterium Candidatus Liberibacter asiaticus (CLas), the causal agent of citrus greening disease, or Huanglongbing (HLB). The widespread invasiveness of the psyllid vector and HLB in citrus trees worldwide has underscored the need for non-traditional approaches to manage the disease. One tenable solution is through the deployment of RNA interference technology to silence protein-protein interactions essential for ACP-mediated CLas invasion and transmission. To identify psyllid interactor-bacterial effector combinations associated with psyllid-CLas interactions, cDNA libraries were constructed from CLas-infected and CLas-free ACP adults and nymphs, and analyzed for differential expression. Library assemblies comprised 24,039,255 reads and yielded 45,976 consensus contigs. They were annotated (UniProt), classified using Gene Ontology, and subjected to in silico expression analyses using the Transcriptome Computational Workbench (TCW) (http://www.sohomoptera.org/ACPPoP/). Functional-biological pathway interpretations were carried out using the Kyoto Encyclopedia of Genes and Genomes databases. Differentially expressed contigs in adults and/or nymphs represented genes and/or metabolic/pathogenesis pathways involved in adhesion, biofilm formation, development-related, immunity, nutrition, stress, and virulence. Notably, contigs involved in gene silencing and transposon-related responses were documented in a psyllid for the first time. This is the first comparative transcriptomic analysis of ACP adults and nymphs infected and uninfected with CLas. The results provide key initial insights into host-parasite interactions involving CLas effectors that contribute to invasion-virulence, and to host nutritional exploitation and immune-related responses that appear to be essential for successful ACP-mediated circulative, propagative CLas transmission.

  15. The myosin motor domain-containing chitin synthase PdChsVII is required for development, cell wall integrity and virulence in the citrus postharvest pathogen Penicillium digitatum.

    Science.gov (United States)

    Gandía, Mónica; Harries, Eleonora; Marcos, Jose F

    2014-06-01

    Chitin is an essential component of the fungal cell wall and a potential target in the development of new antifungal compounds, due to its presence in fungi and not in plants or vertebrates. Chitin synthase genes (chs) constitute a complex family in filamentous fungi and are involved in fungal development, morphogenesis, pathogenesis and virulence. In this study, additional chs genes in the citrus postharvest pathogen Penicillium digitatum have been identified. Comparative analyses included each PdChs in each one of the classes I to VII previously established, and support the grouping of these into three divisions. Disruption of the gene coding PdChsVII, which contains a short version of a myosin motor domain, has been achieved by using Agrobacterium tumefaciens-mediated transformation and revealed its role in the life cycle of the fungus. Disruption strains were viable but showed reduced growth and conidia production. Moreover, Pdchs mutants developed morphological defects as balloon-like enlarged cells and increased chitin content, indicative of an altered cell wall structure. Gene disruption also increased susceptibility to antifungal compounds such as calcofluor white (CFW), sodium dodecyl sulfate (SDS), hydroxide peroxide (H2O2) and commercial fungicides, but significantly no change was observed in the sensitivity to antifungal peptides. The PdchsVII mutants were able to infect citrus fruit and produced tissue maceration, although had reduced virulence and most importantly were greatly impaired in the production of visible mycelium and conidia on the fruit.

  16. Certification Programs for Citrus

    Science.gov (United States)

    Citrus certification programs designed to ensure that healthy plants of the highest genetic potential are being planted in the field are the basic building block of an integrated pest management program. Certification programs began for citrus began with the discovery that the diseases were graft t...

  17. Cercosporoid diseases of Citrus.

    Science.gov (United States)

    Huang, Feng; Groenewald, J Z; Zhu, Li; Crous, P W; Li, Hongye

    2015-01-01

    Citrus leaves and fruits exhibiting disease symptoms ranging from greasy spot, yellow spot, small or large brown spot, black dot, and brown dot were sampled from Fujian, Guangdong, Guizhou, Hunan, Jiangxi, Yunnan, Zhejiang provinces and the Guangxi Zhuang Autonomous Region in China. In total 82 isolates representing various cercosporoid genera were isolated from these disease symptoms, which were supplemented with eight Citrus cercosporoid isolates collected from other countries. Based on a morphological and phylogenetic study using sequence data from the nuclear ribosomal DNA's ITS1-5.8S-ITS2 regions (ITS), and partial actin (act), β-tubulin (tub2), 28S nuclear ribosomal RNA (28S rDNA) and translation elongation factor 1-α (tef1) genes, these strains were placed in the following genera: Cercospora, Pallidocercospora, Passalora, Pseudocercospora, Verrucisporota and Zasmidium. All isolates tended to be sterile, except the Zasmidium isolates associated with citrus greasy spot-like symptoms, which subsequently were compared with phylogenetically similar isolates occurring on Citrus and other hosts elsewhere. From these results four Zasmidium species were recognized on Citrus, namely Z. indonesianum on Citrus in Indonesia, Z. fructicola and Z. fructigenum on Citrus in China and Z. citri-griseum, which appears to have a wide host range including Acacia, Citrus, Eucalyptus and Musa, as well as a global distribution.

  18. Chemical defoliation of apple rootstocks and the influence of rootstocks type on the defoliation of 'Jonathan' scion

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    A. Basak

    2013-12-01

    Full Text Available The following substances were used to defoliate apple rootstock instead of hand defoliation before digging out: KI, CuSO4 · 5H2O, Mg(ClO32< · H2O, ethephon (Ethrel 68-250 and CKB 1131, preparation N252, and the mixtures: ethephon (Ethrel with copper sulphate, or with gibberellic acid, morphactin (EMD with ethephon, and morphactin with ethephon and copper sulphate. Among the inorganic defoliants tested, only Mg(ClO32 · H2O gave satisfactory results in defoliating apple rootstocks. When applied at the end of September this chemical did not decrease winter hardiness of the rootstocks. Ethrel and the preparation CKB 1131,caused satisfactory defoliation, but when used in optimal concentrations for defoliation they decreased the winter hardiness of plants. The mixture of ethephon with copper sulphate in which both components were used in low concentrations also appeared highly effective. Ethephon in low concentration mixed with EMD caused only partial defoliation of the rootstocks. Addition of gibberellic acid did not improve the effectiveness of ethephon. Preparation N252 in a concentration of 0.15% effectively defoliated the rootstocks and did not cause a subsequent decrease of frost hardiness in the conditions of this experiment. The response of 'Jonathan' scions to defoliants was modified by the rootstock.

  19. Utilization of founder lines for improved Citrus biotechnology via RMCE

    Science.gov (United States)

    On October 1st 2011 the CRB chose to fund a unique research project, the development of citrus cultivars specifically for genetic engineering (GE). The objective of this research was to develop GE citrus ‘Founder Lines’ containing DNA sequences that will allow the precise insertion of genes for de...

  20. Development of EST-SSR Markers in (Citrus aurantium L.)%积壳EST-SSR标记的开发

    Institute of Scientific and Technical Information of China (English)

    杨春霞; 温强; 叶金山; 朱培林

    2011-01-01

    The big collection of expressed sequence tags (ESTs) from Citrus aurantium L. is available in public database, and offers an opportunity to identify simple sequence repeats (SSR) in ESTs by data mining. These sequences may provide an estimate of diversity in the expressed portion of the genome and may be useful for comparative mapping, for tagging important traits of interest, and for additional map-based cloning of important genes.We analyzed fiontal 11 029 Unigene sequences fi.om C. aurantium database using online SSR identified software SSRIT. Totally, 327 ESTs with 348 SSRs were identified, and accounted for 2.96% of the total number of EST sequences. Trinucleotide repeats (a total of 161) were the most abundant repeat class, and accounted for 46.26% of all found SSRs. According to these EST sequences containing SSR, 58 primer pairs were designed using Primer 3.0. of these, 36 primer pairs amplified DNA fragments and 6 primer pairs exhibited polymorphism, account for 62.07% and 10.34% of the total designed 58 pairs. The development of new EST-SSR markers from C. aurantium has potential important implication for genetic analysis and exploitation of genetic resources of C. aurantium and would provide a more direct estimate of functional diversity.%GenBank上己公布的积壳EST序列为开发新的SSR标记提供了宝贵的数据资源.本研究利用在线SSR鉴定软件SSRIT分析来自积壳EST数据库的11029条Unigene序列.分析结果共发现327条EST序列含有348个SSR位点,占总数的2.96%.其中,三核苷酸重复的SSR类型最多,共有161个,占检索总数的46.26%. Primer 3.0设计合成58对EST-SSR引物,其中36对能扩增出产物,6对引物产生多态性分离,分别占所设计引物总数的62.07%和10.34%.本文研究成果为今后积壳遗传多样性分析、遗传图谱构建及比较基因组等研究方面奠定了基础.

  1. Rootstock-regulated gene expression patterns associated with fire blight resistance in apple

    Science.gov (United States)

    Background: Desirable apple varieties are clonally propagated by grafting vegetative scions onto rootstocks. Rootstocks influence many phenotypic traits of the scion, including resistance to pathogens such as Erwinia amylovora, which causes fire blight, the most serious bacterial disease of apple....

  2. Abundance of citrus leafminer larvae on citrus and citrus-related germplasm

    Science.gov (United States)

    The citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), is a key pest in most citrus growing regions worldwide. Adult citrus leafminers oviposit primarily on young elongating flush of citrus as well as other Rutaceae and some ornamental plants. Larvae feed on the epiderm...

  3. Detection of Citrus Huanglongbing by Fourier Transform Infrared-Attenuated Total Reflection (FTIR-ATR) Spectroscopy

    Science.gov (United States)

    Citrus Huanglongbing (HLB, also known as citrus greening disease) was discovered in Florida in 2005 and is spreading rapidly amongst the citrus growing regions of the state. Detection via visual symptoms of the disease is not a long term viable option. New techniques are being developed to test fo...

  4. Geneva apple rootstock performance in New York state and progress in commercialization

    Science.gov (United States)

    A number of new apple rootstocks from the Cornell/USDA apple rootstock breeding project, located at Geneva NY which are resistant to the bacterial disease fire blight (Erwinia amylovora) are rapidly becoming available. Some named rootstock genotypes from this program have previously been tested in s...

  5. SELECTION OF VARIETY-ROOTSTOCK COMBINATIONS OF PLUM FOR THE KRASNODAR REGION

    Directory of Open Access Journals (Sweden)

    Sushkov D. N.

    2014-02-01

    Full Text Available The article shows the results of integrated assessment of variety-rootstock combinations of plum on clonal rootstocks and different schemes of landing. We have defined the basic biometric parameters of trees, and specific indicators of productivity, allowing to identify the most optimal variety-stable rootstock combination for the conditions of the Krasnodar region

  6. Evaluation of three rootstocks root system for acid lime ‘tahiti’ at Piauí state/ Sistema radicular de três porta-enxertos para lima ácida ‘tahiti’ no estado do Piauí

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    Adeodato Ari Cavalcante Salviano

    2007-10-01

    Full Text Available The objective of this work was to evaluate the development of the root system of three rootstocks for ‘Tahiti’acid lime [Citrus latifolia (Yu.Tanaka Tanaka]: Rangpur lime (C. limonia Osbeck; Swingle citrumelo [Poncirus trifoliata (L. Raf. x C. paradisi Macf.]; Flying Dragon trifoliate (P. trifoliata (L. Raf.var. (FD – in the soil and environment conditions of the county of José de Freitas, Piauí, located on 04º 52' latitude S and 42º 42' longitude W and 110 m of altitude, in Aw climate. It was used the trench method. A wooden frame divided into 0.1 x 0.2 m parts was fixed in the soil profile and a digital photograph was taken from each part. These photographs were analyzed by software SIARCS 3.0 for sizing of the root system and the data gotten, submitted to the analysis of variance with Tukey test at the level of 5% of probability. The experimental design was entirely randomized, with three treatments (rootstocks and four replications (trenches. The root systems of the rootstocks had 90% of concentration until the depth of 0,4 m, and it was observed that 60% of the roots were concentrated in the first 0,2 m. The root system of the Rangpur lime demonstrated to be superior, in lenght (cm.200 cm-² to the Flying Dragon trifoliate and Swingle citrumelo root systems.O objetivo deste trabalho foi avaliar o desenvolvimento radicular de três porta-enxertos para lima ácida ‘Tahiti’ [Citrus latifolia (Yu.Tanaka Tanaka]: limão Cravo (C. limonia Osbeck; citrumelo Swingle [Poncirus trifoliata (L. Raf. x C. paradisi Macf.]; trifoliata Flying Dragon (P. trifoliata (L. Raf.var. (FD, no município de José de Freitas, Piauí, localizado a 04º 52’ latitude S e 42º 42’ longitude W, e altitude de 110m, onde predomina clima Aw. Foram abertas trincheiras com quatro repetições, para colocação de quadro-gabarito de madeira, com divisórias de 0,1 m na profundidade por 0,2 m na largura, perfazendo cinco camadas na profundidade e seis posi

  7. Transformation of Mexican lime with an intron-hairpin construct expressing untranslatable versions of the genes coding for the three silencing suppressors of Citrus tristeza virus confers complete resistance to the virus.

    Science.gov (United States)

    Soler, Nuria; Plomer, Montserrat; Fagoaga, Carmen; Moreno, Pedro; Navarro, Luis; Flores, Ricardo; Peña, Leandro

    2012-06-01

    Citrus tristeza virus (CTV), the causal agent of the most devastating viral disease of citrus, has evolved three silencing suppressor proteins acting at intra- (p23 and p20) and/or intercellular level (p20 and p25) to overcome host antiviral defence. Previously, we showed that Mexican lime transformed with an intron-hairpin construct including part of the gene p23 and the adjacent 3' untranslated region displays partial resistance to CTV, with a fraction of the propagations from some transgenic lines remaining uninfected. Here, we transformed Mexican lime with an intron-hairpin vector carrying full-length, untranslatable versions of the genes p25, p20 and p23 from CTV strain T36 to silence the expression of these critical genes in CTV-infected cells. Three transgenic lines presented complete resistance to viral infection, with all their propagations remaining symptomless and virus-free after graft inoculation with CTV-T36, either in the nontransgenic rootstock or in the transgenic scion. Accumulation of transgene-derived siRNAs was necessary but not sufficient for CTV resistance. Inoculation with a divergent CTV strain led to partially breaking the resistance, thus showing the role of sequence identity in the underlying mechanism. Our results are a step forward to developing transgenic resistance to CTV and also show that targeting simultaneously by RNA interference (RNAi) the three viral silencing suppressors appears critical for this purpose, although the involvement of concurrent RNAi mechanisms cannot be excluded.

  8. Effects of Different Rootstocks on the Growth and Fruit Quality of Greenhouse Cucumber in Early Spring

    Institute of Scientific and Technical Information of China (English)

    LIU Bing; ZHANG Tianwei; ZHAO Jiayu; JIANG Xinmei

    2009-01-01

    Different pumpkin rootstocks were used to study the effects of different rootstocks on the growth and fruit quality of greenhouse cucumber in early spring. The results showed that the grafted cucumber could significantly improve the production, and different rootstock had a certain effect on the survival rate and fruit quality. Jinhuanghou and Fengyijiajiewang as rootstock had the highest survival rate, which were 79.0% and 70.7%, respectively. As rootstocks of greenhouse cucumber, Jinhuanghou, Lvzhoujuxing,Fengyi, Huofenghuang, and Dawei No.17 were better than others according to taste, and Heizinangua, Jinhuanghou, Fengyi,Huofenghuang, and Dawei No. 17 were better according to output.

  9. A rootstock provides water conservation for a grafted commercial tomato (Solanum lycopersicum L.) line in response to mild-drought conditions: a focus on vegetative growth and photosynthetic parameters.

    Science.gov (United States)

    Nilsen, Erik T; Freeman, Joshua; Grene, Ruth; Tokuhisa, James

    2014-01-01

    The development of water stress resistant lines of commercial tomato by breeding or genetic engineering is possible, but will take considerable time before commercial varieties are available for production. However, grafting commercial tomato lines on drought resistant rootstock may produce drought tolerant commercial tomato lines much more rapidly. Due to changing climates and the need for commercial production of vegetables in low quality fields there is an urgent need for stress tolerant commercial lines of vegetables such as tomato. In previous observations we identified a scion root stock combination ('BHN 602' scion grafted onto 'Jjak Kkung' rootstock hereafter identified as 602/Jjak) that had a qualitative drought-tolerance phenotype when compared to the non-grafted line. Based on this initial observation, we studied photosynthesis and vegetative above-ground growth during mild-drought for the 602/Jjak compared with another scion-rootstock combination ('BHN 602' scion grafted onto 'Cheong Gang' rootstock hereafter identified as 602/Cheong) and a non-grafted control. Overall above ground vegetative growth was significantly lower for 602/Jjak in comparison to the other plant lines. Moreover, water potential reduction in response to mild drought was significantly less for 602/Jjak, yet stomatal conductance of all plant-lines were equally inhibited by mild-drought. Light saturated photosynthesis of 602/Jjak was less affected by low water potential than the other two lines as was the % reduction in mesophyll conductance. Therefore, the Jjak Kkung rootstock caused aboveground growth reduction, water conservation and increased photosynthetic tolerance of mild drought. These data show that different rootstocks can change the photosynthetic responses to drought of a high yielding, commercial tomato line. Also, this rapid discovery of one scion-rootstock combination that provided mild-drought tolerance suggests that screening more scion-rootstock combination for

  10. A rootstock provides water conservation for a grafted commercial tomato (Solanum lycopersicum L. line in response to mild-drought conditions: a focus on vegetative growth and photosynthetic parameters.

    Directory of Open Access Journals (Sweden)

    Erik T Nilsen

    Full Text Available The development of water stress resistant lines of commercial tomato by breeding or genetic engineering is possible, but will take considerable time before commercial varieties are available for production. However, grafting commercial tomato lines on drought resistant rootstock may produce drought tolerant commercial tomato lines much more rapidly. Due to changing climates and the need for commercial production of vegetables in low quality fields there is an urgent need for stress tolerant commercial lines of vegetables such as tomato. In previous observations we identified a scion root stock combination ('BHN 602' scion grafted onto 'Jjak Kkung' rootstock hereafter identified as 602/Jjak that had a qualitative drought-tolerance phenotype when compared to the non-grafted line. Based on this initial observation, we studied photosynthesis and vegetative above-ground growth during mild-drought for the 602/Jjak compared with another scion-rootstock combination ('BHN 602' scion grafted onto 'Cheong Gang' rootstock hereafter identified as 602/Cheong and a non-grafted control. Overall above ground vegetative growth was significantly lower for 602/Jjak in comparison to the other plant lines. Moreover, water potential reduction in response to mild drought was significantly less for 602/Jjak, yet stomatal conductance of all plant-lines were equally inhibited by mild-drought. Light saturated photosynthesis of 602/Jjak was less affected by low water potential than the other two lines as was the % reduction in mesophyll conductance. Therefore, the Jjak Kkung rootstock caused aboveground growth reduction, water conservation and increased photosynthetic tolerance of mild drought. These data show that different rootstocks can change the photosynthetic responses to drought of a high yielding, commercial tomato line. Also, this rapid discovery of one scion-rootstock combination that provided mild-drought tolerance suggests that screening more scion-rootstock

  11. Investigações sôbre a tristeza dos Citrus: II - Conceitos e dados sôbre a reação das plantas cítricas à tristeza

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    A. S. Costa

    1949-01-01

    Full Text Available The writers review previous concepts concerning the reaction of citrus plants to the tristeza disease. It is recognized that environmental factors such as temperature, humidity and light can influence plant reaction, but these are considered of relatively minor importance. Characteristics of the plant itself govern its reaction to the disease and among those, resistance to infection, ability to permit virus increase and tolerance or non-tolerance of tissues are considered most important. Tests using viruliferous oriental citrus aphids for inoculation of various citrus types budded over sour orange rootstocks (table 1 and 2 showed a correlation between susceptibility to infection and severity of symptoms. The sweet oranges proved to be the most susceptible to infection and showed severe disease symptoms. The Barão sweet orange appeared to be more susceptible than Valencia. The mandarins tended to show some resistance to infection, but when infected, severe symptoms developed. The tolerant tangelos (7 behaved similarly to sweet oranges : They were very susceptible to infection and showed severe symptoms. The non-tolerant tangelos, susceptible citranges (7 and grapefruits behaved more or less alike, and showed medium susceptibility to infection and moderately severe disease symptoms. Among the grapefruits, Leonardy was. observed to be relatively more susceptible and showed more severe symptoms than Duncan. The pummelos, shaddocks and sour oranges were comparatively very resistant to infection and showed only moderate symptoms when infected. It has been found that the sour oranges can be more easily infected by tissue union than by the aphid vector. Poncirus trifoliata, citrumelos and resistant citranges showed no symptoms and no virus could be recovered from the inoculated plants even after three inoculations. The nature of injury caused by tristeza in the non-tolerant graft and intergraft combinations is discussed. The observation of symptoms

  12. Apple tree production in Italy: rootstocks, cultivars, fertilization, and irrigation

    Directory of Open Access Journals (Sweden)

    Giovambattista Sorrenti

    2012-11-01

    Full Text Available Italy is one of the main apple producers in Europe, primarily intended for fresh consumption, both in the domestic and foreign markets. Fruit yield and quality depends on the cultivar, rootstock, and management practices, such as the fertilization and irrigation adopted in the orchard. This review aims at reporting the main apple cultivars and rootstocks, the management of fertilization and irrigation, as well as their adaptation to apple tree orchards in Italy. The programs for genetic improvement carried out in this country involved the selection of apple tree cultivars and rootstocks which enable a high fruit yield and quality, in order to meet the requirements from the consumer market. In the fertilization and irrigation management, nutrients and water are supplied in amounts next to the actual need of the plants, providing an adequate nutrition, a satisfactory yield, and high quality fruits, besides preventing, whenever possible, nutrients and water losses in the environment.

  13. Tetranychus urticae-triggered responses promote genotype-dependent conspecific repellence or attractiveness in citrus.

    Science.gov (United States)

    Agut, Blas; Gamir, Jordi; Jaques, Josep A; Flors, Victor

    2015-08-01

    The citrus rootstocks sour orange and Cleopatra mandarin display differential resistance against Tetranychus urticae. Sour orange plants support reduced oviposition, growth rates and damage compared with Cleopatra mandarin plants. Jasmonic acid signalling and flavonoid accumulation have been revealed as key mechanisms for the enhanced resistance of sour orange plants. In this study, we observed that the release of T. urticae herbivore-induced plant volatiles (HIPVs) from sour orange plants has a marked repellent effect on conspecific mites associated with the production of the terpenes α-ocimene, α-farnesene, pinene and d-limonene, and the green leaf volatile 4-hydroxy-4-methyl-2-pentanone. By contrast, T. urticae HIPVs from Cleopatra mandarin plants promote conspecific mite attraction associated with an increase in (2-butoxyethoxy) ethanol, benzaldehyde and methyl salicylate levels. HIPVs released from sour orange plants following T. urticae infestation induce resistance in Cleopatra mandarin plants, thereby reducing oviposition rates and stimulating the oxylipin biosynthetic gene lipoxygenase2 (LOX2). Cleopatra HIPVs do not affect the response to T. urticae of these rootstocks. We conclude that sour orange plants promote herbivore-induced resistance in Cleopatra mandarin plants and, despite the weak basal resistance of these rootstocks, herbivore resistance can be induced through the combination of HIPVs, such as α-ocimene and d-limonene.

  14. Computational identification of citrus microRNAs and target analysis in citrus expressed sequence tags.

    Science.gov (United States)

    Song, C; Jia, Q; Fang, J; Li, F; Wang, C; Zhang, Z

    2010-11-01

    MicroRNAs (miRNAs) are a new family of small RNA molecules found in plants and animals. We developed a comprehensive strategy for identifying new miRNA homologues by mining the repository of available citrus expressed sequence tags (ESTs). By adopting a range of filtering criteria, we identified a total of 38 potential miRNAs--nine, five, nine and 15 miRNAs in Citrus trifoliata (ctr-miRNAs), C. clementina (ccl-miRNAs), C. reticulata (crt-miRNAs) and C. sinensis (csi-miRNAs), respectively--from more than 430,000 EST sequences in citrus. Using the potential miRNA sequences, we conducted a further BLAST search of the mRNA database and found six potential target genes in these citrus species. Eight miRNAs were selected in order to verify their existence in citrus using Northern blotting, and the functions of several miRNAs in miRNA-mediated gene regulation are experimentally suggested. It appears that all these miRNAs regulate expression of their target genes by cleavage, which is the most common situation in gene regulation mediated by plant miRNAs. Our achievement in identifying new miRNAs in citrus provides a powerful incentive for further studies on the important roles of these miRNAs.

  15. Citrus diseases with global ramifications including citrus canker and huanglongbing

    Science.gov (United States)

    Although there are a number of diseases that plague citrus production worldwide, two bacterial diseases are particularly problematic. Both are of Asian origin and currently cause severe economic damage: Asiatic citrus canker (ACC) and citrus huanglongbing (HLB). Although ACC has been found in the ...

  16. Avaliação do enraizamento, desenvolvimento de raízes e parte aérea de porta-enxertos de videira em condições de campo Evaluation of rooting, development of roots and shoot biomass from rootstock of grapevine, in field conditions

    Directory of Open Access Journals (Sweden)

    Marco Antonio Tecchio

    2007-12-01

    Full Text Available Objetivou-se neste trabalho avaliar o enraizamento, a brotação e o desenvolvimento de raízes de diferentes porta-enxertos de videira em condições de campo. Estacas lenhosas dos porta-enxertos '420 A', 'Golia', '5C', '8B', 'RR101-14', 'SO4', '99R', 'Kober 5BB', 'IAC 766', 'IAC 572', 'IAC 571-6', 'Ripária do Traviú' e 'Rupestris du Lot' foram colocadas em canteiro de terra, sem tratamento prévio. O delineamento foi em blocos ao acaso, com cinco repetições e vinte estacas por parcela, com as estacas dispostas em espaçamento de 12 x 5cm. As estacas foram colocadas para enraizar no início de julho e removidas no final de setembro para as avaliações. A porcentagem de estacas enraizadas variou de 79% para 'Ripária do Traviú' a 99% para o 'RR101-14'. Quanto à brotação, o 'Ripária do Traviú' apresentou 47%, 'IAC 571-6', 'IAC 572', '420 A', 'Rupestris du Lot', 'Kober', 'IAC 766', '8B', '5C', apresentaram de 76 a 89% e 'Golia', 'SO4', '99R' e 'RR 101-14' mais de 90%. 'IAC 572' e 'IAC 571-6' apresentaram o menor número de raízes por estaca, no entanto, foram as que apresentaram raízes mais desenvolvidas, seguidas pelo '5C' e 'Rupestris du Lot'. 'Kober 5BB' e 'Ripária do Traviú' apresentaram as raízes menos desenvolvidas. As demais variedades apresentaram valores intermediários. Concluiu-se que, entre todos os porta-enxertos, o 'Ripária do Traviú' apresentou os menores índices de enraizamento e brotação das estacas, nas condições de campo.The goals of this investigation was to evaluate the rooting, budding and development of roots from different rootstock of grapevine, in field conditions. Ligneous cutting of rootstock '420 A', 'Golia', '5C', '8B', 'RR101-14', 'SO4', '99R', 'Kober 5BB', 'IAC 766', 'IAC 572', 'IAC 571-6', 'Ripária do Traviú' and 'Rupestris du Lot' were planted in soil, without previous preparation. The experimental design was done in randomized blocks, with five repetitions and twenty cutting per plot

  17. PHARMACOLOGICAL IMPORTANCE OF CITRUS FRUITS

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    Amita Tomar *, Mridula Mall and Pragya Rai

    2013-01-01

    Full Text Available This paper reviews the pharmacological importance of citrus fruits. Citrus fruits are used for various pharmacological importance. According to literature the citrus fruit possess anti-cancer, antimicrobial, antioxidant, antiulcer, anti-inflammatory, and hypolipidemic and hepatoprotective properties.

  18. Repartição de nutrientes nas flores, folhas e ramos da laranjeira cultivar Natal Repartition of nutrients in citrus flowers, leaves and branches

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    Eurípedes Malavolta

    2006-12-01

    Full Text Available As plantas cítricas produzem elevado número de flores, porém pequena porcentagem chega a fruto maduro. A fixação é influenciada por diversos fatores, com destaque para os nutricionais orgânicos e minerais. O objetivo do trabalho foi verificar a repartição de macro e micronutrientes nas flores, folhas e ramos de laranjeira e a contribuição nutricional das flores para os demais órgãos. Plantas de Citrus sinensis L., cultivar Natal sobre porta-enxerto de limoeiro cravo de 10 anos de idade, provenientes de pomar comercial, foram amostradas por ocasião do fluxo primaveril e separadas em flores, folhas e ramos. As flores representam dreno tanto para compostos orgânicos quanto para macro e micronutrientes. Sua massa seca na antese se iguala às das folhas e é maior que a dos ramos. A maior proporção de Ca, Mg e de Ni das três partes encontram-se nas flores de onde, possivelmente, passam em parte para o fruto em desenvolvimento. Sugere-se que aplicações foliares de cálcio, magnésio e níquel, em condições de deficiência, poderiam aumentar a produção através do seu efeito no florescimento.Citrus plants produce a number of flowers, but just a few of them however, become mature fruits. Many factors, as well as organic and inorganic nutrients, influence prebloom and flowers setting. The objective of this work was to evaluate the repartition of macro and micronutrients in citrus flowers, leaves and branches. Branches of "Natal" sweet orange (Citrus sinensis L. grafted on Rangpur lime rootstock were collected and separated in flowers, leaves and wood during anthesis. Orange flowers represent a drain for organic compounds and macro and micronutrients as well. Their dry matter on anthesis is equal to that of leaves and higher than that of the branches. The highest proportion of Ca, Mg and Ni of the three parts is found in the flowers where possibly migrate in part, into the developing fruits. It is thought that leaf sprays of

  19. Geneva rootstocks for weak growing scion cultivars like Honeycrisp

    Science.gov (United States)

    Duplicate field trials with ‘Honeycrisp’ apple on 22 rootstocks conducted for 9 years at Geneva, NY (in Western NY State) and Peru, NY (in Northern NY State), showed that two dwarf Geneva® stocks (G.41 and G.11) had good tree survival, superior yield performance to M.9, similar fruit size as M.9 and...

  20. Incremento no desenvolvimento do porta-enxerto de pessegueiro "Aldrighi" por fungos micorrízicos arbusculares autóctones Development increase of 'Aldrighi' peach rootstocks by indigenous arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    José Luis da Silva Nunes

    2008-12-01

    Full Text Available Objetivou-se, neste trabalho, avaliar a influência de três espécies de fungos micorrízicos arbusculares (FMA isolados de pomares de pessegueiro sobre o crescimento vegetativo, nutrição mineral e substâncias de reserva em plantas do porta-enxerto de pessegueiro cv. Aldrighi [Prunus persica (L. Batsch]. O delineamento experimental utilizado foi o de blocos casualizados, com dez plantas por parcela e quatro repetições. As plantas inoculadas com Glomus etunicatum apresentaram maior altura, diâmetro, área foliar, biomassa fresca e seca, nutrição mineral e substâncias de reserva da parte aérea, enquanto as inoculadas com Glomus clarum induziram um crescimento intermediário, superior àquelas inoculadas com Gigaspora margarita, que apresentaram resultados semelhantes às plantas não inoculadas. O desempenho foi relacionado com as taxas de colonização que nas plantas inoculadas com Glomus etunicatum e Glomus clarum foram de 92% e 77% respectivamente, enquanto Gigaspora margarita colonizou somente 30% das raízes.This work aimed to evaluate the influence of three arbuscular mycorrhizal fungi (AMF species on the vegetative growth, mineral nutrition and carbohidrate contents on peach rootstocks cv. Aldrighi [Prunus persica (L. Batsch]. The experimental desing was the one of randomized blocks, with ten plants per plots and four repetitions. Plants inoculated with Glomus etunicatum presented larger stem height, stem diameter, foliar area, fresh and dry shoot biomass, leaf mineral nutrition and carbohidrate contents, while those inoculated with Glomus clarum induced an intermediate growth, higher to those inoculated with Gigaspora margarita that presented results similar to the non inoculated plants. Plant growth performance was related to colonization taxes, which were, respectively, 92%, 77% and 30% to Glomus etunicatum, Glomus clarum and Gigaspora margarita inoculated plants.

  1. Antioxidant activity of Citrus fruits.

    Science.gov (United States)

    Zou, Zhuo; Xi, Wanpeng; Hu, Yan; Nie, Chao; Zhou, Zhiqin

    2016-04-01

    Citrus is well-known for its nutrition and health-promotion values. This reputation is derived from the studies on the biological functions of phytochemicals in Citrus fruits and their derived products in the past decades. In recent years, the antioxidant activity of Citrus fruits and their roles in the prevention and treatment of various human chronic and degenerative diseases have attracted more and more attention. Citrus fruits are suggested to be a good source of dietary antioxidants. To have a better understanding of the mechanism underlying the antioxidant activity of Citrus fruits, we reviewed a study on the antioxidant activity of the phytochemicals in Citrus fruits, introduced methods for antioxidant activity evaluation, discussed the factors which influence the antioxidant activity of Citrus fruits, and summarized the underlying mechanism of action. Some suggestions for future study were also presented.

  2. Asian Citrus Psyllid RNAi Pathway – RNAi evidence

    Science.gov (United States)

    Taning, Clauvis N. T.; Andrade, Eduardo C.; Hunter, Wayne B.; Christiaens, Olivier; Smagghe, Guy

    2016-01-01

    Diaphorina citri, known as the Asian citrus psyllid, is an important pest of citrus because it transmits a phloem-limited bacteria strongly implicated in huanglongbing (citrus greening disease). Emerging biotechnologies, such as RNA interference, could provide a new sustainable and environmentally friendly strategy for the management of this pest. In this study, genome and functional analysis were performed to verify whether the RNAi core genes are present in the Asian psyllid genome and if the RNAi machinery could be exploited to develop a management strategy for this pest. Analyses of RNAi-related genes in the Asian citrus psyllid genome showed an absence of sequences encoding R2D2, a dsRNA-binding protein that functions as a cofactor of Dicer-2 in Drosophila. Nevertheless, bioassays using an in Planta System showed that the Asian citrus psyllid was very sensitive to ingested dsRNA, demonstrating a strong RNAi response. A small dose of dsRNA administered through a citrus flush was enough to trigger the RNAi mechanism, causing significant suppression of the targeted transcript, and increased psyllid mortality. This study provides evidence of a functional RNAi machinery, which could be further exploited to develop RNAi based management strategies for the control of the Asian citrus psyllid. PMID:27901078

  3. Founder lines for improved citrus biotechnology

    Science.gov (United States)

    This article discusses the research needed to develop the RMCE strategy and molecular assays for site-specific recombinases as tools for genome manipulation. Explanation of genetic engineering used to generate transgenic citrus plants to exhibit a novel phenotype, but not to contain the recombinase...

  4. Rizobactérias e promoção do crescimento de plantas cítricas Rhizobacteria and growth promotion of citrus plants

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    S. S. Freitas

    2004-12-01

    Full Text Available Desenvolveram-se três experimentos em casa de vegetação para verificar a possibilidade de as rizobactérias atuarem como promotoras do crescimento de plantas cítricas. Ao todo, testaram-se 10 isolados de Pseudomonas do grupo fluorescente, 13 de Bacillus e sete de outras bactérias rizosféricas em porta-enxertos utilizados na citricultura: tangerineira 'Cleópatra' (Citrus reshni, limoeiro 'Cravo' (Citrus limonia e limoeiro 'Volcameriano' (Citrus volkameriana. Dependendo do porta-enxerto, sete isolados de Pseudomonas, um de Bacillus e um de outra bactéria rizosférica tiveram efeito benéfico sobre a matéria seca de raízes ou de parte aérea, indicando uma alta proporção de promotores de crescimento entre as bactérias do primeiro grupo. Procedeu-se também à contagem de bactérias fluorescentes do gênero Pseudomonas e de bactérias não-fluorescentes em raízes de tangerineira 'Cleópatra' e de limoeiro 'Cravo', procedentes de viveiro de mudas e do campo. Ambos os grupos bacterianos tiveram sua multiplicação favorecida na rizosfera de tangerineira 'Cleópatra', em condições de viveiro.Three greenhouse trials were carried out to verify if rhizobacteria can promote citrus plant growth. Ten isolates of fluorescent Pseudomonads, thirteen of Bacillus spp. and seven of other rhizospheric bacteria were tested in three rootstocks seedlings: 'Cleopatra' mandarin (Citrus reshni, rangpure lime (Citrus limonia and Volkamerian lemon (Citrus volkameriana. Depending on the rootstock, seven Pseudomonads, one isolate of Bacillus and one of other rhizospheric bacteria increased the root or shoot dry weight, indicating a high proportion of growth promoters among the fluorescent Pseudomonads. Also, fluorescent Pseudomonads and non fluorescent bacteria were counted in the roots of nursery seedlings and field plants of Citrus reshni and Citrus limonia. The growth of both bacterial groups was favored in the Citrus reshni rhizosphere under nursery

  5. Growth and Photosynthetic Response of Two Persimmon Rootstocks (Diospyros kaki and D. virginiana under Different Salinity Levels

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    Meral INCESU

    2014-12-01

    Full Text Available Salinity continues to be a major factor in reduced crop productivity and profit in many arid and semiarid regions. Seedlings of Diospyros kaki Thunb. and D. virginiana L. are commonly used as rootstock in persimmon cultivation. In this study we have evaluated the effects of different salinity levels on photosynthetic capacity and plant development of D. kaki and D. virginiana. Salinity was provided by adding 50 mM, 75 mM and 100 mM NaCl to nutrient solution. In order to determine the effects of different salinity levels on plant growth, leaf number, plant height, shoot and root dry mass were recorded. Besides leaf Na, Cl, K and Ca concentrations were determined. Also leaf chlorophyll concentration, chlorophyll fluorescence (Fv’/Fm’ and leaf gas exchange parameters including leaf net photosynthetic rate (PN, stomatal conductance (gS, leaf transpiration rate (E, and CO2 substomatal concentration (Ci were investigated. Significant decrease of leaf number, shoot length and plant dry mass by increasing salinity levels was observed in both rootstocks. D. virginiana was less affected in terms of plant growth under salinity stress. Leaf chlorophyll concentration reduction was higher in the leaves of D. kaki in comparison to D. virginiana in 100 mM NaCl treatment. By increasing salinity levels PN, gS and E markedly decreased in both rootstocks and D. kaki was more affected from salinity in terms of leaf gas exchange parameters. In addition there was no significant difference but slight decreases were recorded in leaf chlorophyll fluorescences of both rootstocks.

  6. Physiological Mechanism on the Difference of Sugar Accumulation in Four Citrus Varieties

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhi-zhong; ZHANG Shang-long; LIU Shuan-tao; CHEN Jun-wei; TAO Jun

    2003-01-01

    The concentration of sucrose,glucose,fructose,titratable acid,ABA and the activity of acid invertase(AI)were measured injuice sacs of Bendizao mandarin(Citrus succosa Hort),Ponkan(Citrus reticulata Blanco),Miyagawa wase(Citrus unshiu Marc)and Meyer lemon(Citrus,meyeri Y).The acid hydrolysis of sucrose in vitro was also studied.The results showed that the sugar content,the ratio of different sugars,titratable acidity,ABA content and the activity of AI were obviously different in four citrus varieties.The sugar content inj uice sacs of citrus fruit was related to that of ABA at the late stage of fruit development.The result suggested that ABA played an important role in sugar accumulation in juice sacs of citrus fruit.Bendizao mandarin and Miyagawa wase mainly accumulated sucrose inj uice sacs of citrus fruit.Meyer lemon accumulated hexose,and Ponkan citrus was the sucrose-hexose accumulating type variety.In Meyer lemon with high acid degree,the composition of sugar inj uice sacs was determined by acid-hydrolysis of sucrose.In Bendizao mandarin,Ponkan citrus and Miyagawa wase with low acid degree,the composition of sugars at the late stage of fruit development was obviously affected by the AI activity.

  7. Effective antibiotics against 'Candidatus Liberibacter asiaticus' in HLB-affected citrus plants identified via the graft-based evaluation.

    Science.gov (United States)

    Zhang, Muqing; Guo, Ying; Powell, Charles A; Doud, Melissa S; Yang, Chuanyu; Duan, Yongping

    2014-01-01

    Citrus huanglongbing (HLB), caused by three species of fastidious, phloem-limited 'Candidatus Liberibacter', is one of the most destructive diseases of citrus worldwide. To date, there is no established cure for this century-old and yet, newly emerging disease. As a potential control strategy for citrus HLB, 31 antibiotics were screened for effectiveness and phytotoxicity using the optimized graft-based screening system with 'Candidatus Liberibacter asiaticus' (Las)-infected citrus scions. Actidione and Oxytetracycline were the most phytotoxic to citrus with less than 10% of scions surviving and growing; therefore, this data was not used in additional analyses. Results of principal component (PCA) and hierarchical clustering analyses (HCA) demonstrated that 29 antibiotics were clustered into 3 groups: highly effective, partly effective, and not effective. In spite of different modes of actions, a number of antibiotics such as, Ampicillin, Carbenicillin, Penicillin, Cefalexin, Rifampicin and Sulfadimethoxine were all highly effective in eliminating or suppressing Candidatus Liberibacter asiaticus indicated by both the lowest Las infection rate and titers of the treated scions and inoculated rootstock. The non-effective group, including 11 antibiotics alone with three controls, such as Amikacin, Cinoxacin, Gentamicin, Kasugamycin, Lincomycin, Neomycin, Polymixin B and Tobramycin, did not eliminate or suppress Las in the tested concentrations, resulting in plants with increased titers of Las. The other 12 antibiotics partly eliminated or suppressed Las in the treated and graft-inoculated plants. The effective and non-phytotoxic antibiotics could be potential candidates for control of citrus HLB, either for the rescue of infected citrus germplasm or for restricted field application.

  8. Cercosporoid diseases of Citrus

    NARCIS (Netherlands)

    Huang, Feng; Groenewald, J.Z.; Zhu, Li; Crous, P.W.; Li, Hongye

    2015-01-01

    Citrus leaves and fruits exhibiting disease symptoms ranging from greasy spot, yellow spot, small or large brown spot, black dot, and brown dot were sampled from Fujian, Guangdong, Guizhou, Hunan, Jiangxi, Yunnan, Zhejiang provinces and the Guangxi Zhuang Autonomous Region in China. In total 82 isol

  9. Enumerative and binomial sampling plans for citrus mealybug (Homoptera: pseudococcidae) in citrus groves.

    Science.gov (United States)

    Martínez-Ferrer, María Teresa; Ripollés, José Luís; Garcia-Marí, Ferran

    2006-06-01

    The spatial distribution of the citrus mealybug, Planococcus citri (Risso) (Homoptera: Pseudococcidae), was studied in citrus groves in northeastern Spain. Constant precision sampling plans were designed for all developmental stages of citrus mealybug under the fruit calyx, for late stages on fruit, and for females on trunks and main branches; more than 66, 286, and 101 data sets, respectively, were collected from nine commercial fields during 1992-1998. Dispersion parameters were determined using Taylor's power law, giving aggregated spatial patterns for citrus mealybug populations in three locations of the tree sampled. A significant relationship between the number of insects per organ and the percentage of occupied organs was established using either Wilson and Room's binomial model or Kono and Sugino's empirical formula. Constant precision (E = 0.25) sampling plans (i.e., enumerative plans) for estimating mean densities were developed using Green's equation and the two binomial models. For making management decisions, enumerative counts may be less labor-intensive than binomial sampling. Therefore, we recommend enumerative sampling plans for the use in an integrated pest management program in citrus. Required sample sizes for the range of population densities near current management thresholds, in the three plant locations calyx, fruit, and trunk were 50, 110-330, and 30, respectively. Binomial sampling, especially the empirical model, required a higher sample size to achieve equivalent levels of precision.

  10. Potential Nutritional Benefits of Current Citrus Consumption

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    Tami Turner

    2013-03-01

    Full Text Available Citrus contains nutrients and phytochemicals that may be beneficial for health. We collected citrus production and consumption data and estimated the amount of these compounds that are consumed. We then compared the amounts of citrus and citrus-derived compounds used in studies that suggest a health benefit to the amounts typically found in citrus. Data is scarce, but suggests that citrus consumption might improve indices of antioxidant status, and possibly cardiovascular health and insulin sensitivity.

  11. Contrasting Susceptibilities to Flavescence Dorée in Vitis vinifera, Rootstocks and Wild Vitis Species

    Science.gov (United States)

    Eveillard, Sandrine; Jollard, Camille; Labroussaa, Fabien; Khalil, Dima; Perrin, Mireille; Desqué, Delphine; Salar, Pascal; Razan, Frédérique; Hévin, Cyril; Bordenave, Louis; Foissac, Xavier; Masson, Jean E.; Malembic-Maher, Sylvie

    2016-01-01

    Flavescence dorée (FD) is a quarantine disease of grapevine, involving interactions between the plants, leafhopper vectors, and FD phytoplasma. Characterizing the susceptibility of vine varieties could limit disease propagation. After extensive surveys in vineyards, we showed that Cabernet Sauvignon (CS) is highly susceptible, with a high proportion of symptomatic branches and phytoplasma titers, in contrast to Merlot (M). Localized insect transmissions and grafting showed that phytoplasma circulate in the whole plant in the CS cultivar, but in M they are restricted to the transmission point. Insect-mediated transmission under high confinement mimicking natural conditions confirmed these phenotypes and allowed the classification of 28 Vitis accessions into three distinct categories, according to the percentage of infected plants and their phytoplasma titers. Reduced symptoms, low phytoplasma titers, and low percentages of infected plants were found to be associated in the Vitis vinifera cultivars tested. Interestingly, the low susceptibility of M was observed for one of its parents, i.e., Magdeleine Noire des Charentes. Rootstocks and their Vitis parents, although having high percentages of infected plants and intermediate to high phytoplasma titers, shared a symptomless response. This is troubling, because rootstocks can constitute a silent reservoir of contamination in mother plants or when they grow wild nearby vineyards. Altogether, data suggest distribution of genetic traits within the Vitis genus involved in insect-mediated phytoplasma transmission, multiplication, circulation, and symptom development. PMID:27965681

  12. A new three-locus model for rootstock-induced dwarfing in apple revealed by genetic mapping of root bark percentage

    Science.gov (United States)

    Harrison, Nicola; Harrison, Richard J.; Barber-Perez, Nuria; Cascant-Lopez, Emma; Cobo-Medina, Magdalena; Lipska, Marzena; Conde-Ruíz, Rebeca; Brain, Philip; Gregory, Peter J.; Fernández-Fernández, Felicidad

    2016-01-01

    Rootstock-induced dwarfing of apple scions revolutionized global apple production during the twentieth century, leading to the development of modern intensive orchards. A high root bark percentage (the percentage of the whole root area constituted by root cortex) has previously been associated with rootstock-induced dwarfing in apple. In this study, the root bark percentage was measured in a full-sib family of ungrafted apple rootstocks and found to be under the control of three loci. Two quantitative trait loci (QTLs) for root bark percentage were found to co-localize to the same genomic regions on chromosome 5 and chromosome 11 previously identified as controlling dwarfing, Dw1 and Dw2, respectively. A third QTL was identified on chromosome 13 in a region that has not been previously associated with dwarfing. The development of closely linked sequence-tagged site markers improved the resolution of allelic classes, thereby allowing the detection of dominance and epistatic interactions between loci, with high root bark percentage only occurring in specific allelic combinations. In addition, we report a significant negative correlation between root bark percentage and stem diameter (an indicator of tree vigour), measured on a clonally propagated grafted subset of the mapping population. The demonstrated link between root bark percentage and rootstock-induced dwarfing of the scion leads us to propose a three-locus model that is able to explain levels of dwarfing from the dwarf ‘M.27’ to the semi-invigorating rootstock ‘M.116’. Moreover, we suggest that the QTL on chromosome 13 (Rb3) might be analogous to a third dwarfing QTL, Dw3, which has not previously been identified. PMID:26826217

  13. Study on the Relationship between Rootstock Varieties and the Survival Rate of Shoot-tip Grafting%砧木品种与茎尖嫁接成活率关系的研究

    Institute of Scientific and Technical Information of China (English)

    刘科宏

    2012-01-01

    [ Objective] The aim was to study the relationship between rootslock varieties and the survival rate of shool-tip grafting. [ Method] Poncirus trifoliata, Ruta "Citrange" and Citrus sinensis (L. ) Osbeck were prepared for rootstock in vitro. The citrus tristeza virus (CTV) of Huangguo, Changtai, Yuhuan Gaorheng and Yuhuan pomelo was eliminated by shoot-tip grafting using "T"method. [ Result] The highest shoot-tip grafting survival rale of Huangguo and Yuhuan Gaocheng grafted on Citrus sinensis ( L. ) Osbeck was 75.0% and 60.0% respectively. And the highest shoot-tip grafting survival rate of Changtai and Yuhuan pomelo grafted on Ruta "CUrange" was 46. 7% and 18. 2% respectively. [Conclusion] The shoot-lip grafting survival rate was related to the compatibility of rootstock varieties and cultivate. The survival rale of the same cultivars grafted on different rootstock varieties was different.%[目的]明确砧木品种与茎尖嫁接成活率的关系.[方法]分别以枳(Poncirus trifoliota)、枳橙(Ruta“Citrange”)和甜橙[Citrus sinensis(L.)Osbeck]作为茎尖嫁接砧木,采用倒“T”字法对黄果柑、长泰芦柑、玉环高橙以及玉环柚进行茎尖嫁接脱毒.[结果]黄果柑和玉环高橙用甜橙作砧木成活率最高分别为75.0%和60.0%,长泰芦柑和玉环柚用枳橙作砧木成活率最高分别为46.7%和18.2%.[结论]茎尖嫁接成活率的高低与砧木和脱毒品种的亲和性有关,同一品种选用不同的砧木其茎尖嫁接成活率有差异.

  14. Compatibilidade de enxertia de cultivares de marmeleiros com pereiras Compatibility of pear cultivars on quinces rootstocks

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    Zeni Fonseca Pinto Tomaz

    2009-12-01

    Full Text Available A insuficiência de estudos sobre compatibilidade de porta-enxertos é um dos fatores limitantes ao desenvolvimento da cultura da pereira (Pyrus sp. no Brasil. A utilização do marmeleiro (Cydonia oblonga como porta-enxerto para a cultura da pereira apresenta inúmeras vantagens, entre as quais a redução do vigor e a rápida entrada em produção; todavia, sua combinação com algumas cultivares copa apresenta problemas de incompatibilidade de enxertia, podendo ocasionar a ruptura do caule das plantas no pomar. Objetivou-se, neste trabalho, avaliar a compatibilidade de enxertia de algumas cultivares de marmeleiros ('Quince C' e 'Adams' com pereiras ('Packham's Triumph' e 'Kieffer'. As variáveis analisadas foram: diâmetro da secção do tronco no ponto de enxertia, 5 cm abaixo e 5 cm acima do ponto de enxertia, diferença do diâmetro entre porta-enxerto e copa, altura das plantas, volume e massa seca da copa e raízes. Além disso, efetuou-se a observação da conexão vascular no ponto de enxertia através da imersão da base das plantas (abaixo do ponto de enxertia, em solução corante de Ácido Fuccínico 0,08%. Concluiu-se que a cultivar 'Packham's Triumph'apresenta compatibilidade de enxertia com o marmeleiro cultivares 'Adams'e 'Quince C', enquanto o híbrido 'Kieffer' apresentou sintomas morfológicos de incompatibilidade de enxertia com o marmeleiro cultivares 'Quince C' e 'Adams'.The lack of studies on compatibility of pear cultivars and rootstocks is one of the limiting factors on the development of the pear crop in Brazil. The use of quinces as rootstocks for pear cultivars has several advantages, among them the reduction in vigor and earlier bearing trees, however, its combination with some scions cultivars results in problems of incompatibility , such as lost of trees of the orchard due to break of the graft union. The objective of this study was to determine the compatibility between pears cvs. Packham's Triumph and Kieffer

  15. Somatic hybridization between Citrus sinensis (L. Osbeck and C. grandis (L. Osbeck Hibridação somática entre Citrus sinensis (L. Osbeck e C. grandis (L. Osbeck

    Directory of Open Access Journals (Sweden)

    Marcia Cristina Calixto

    2004-07-01

    Full Text Available This work had as objective to produce citrus somatic hybrids between sweet oranges and pummelos. After chemical fusion of sweet orange embryogenic protoplasts with pummelo mesophyll-derived protoplasts, plants were regenerated by somatic embryogenesis and acclimatized in a greenhouse. The hybrids of 'Hamlin' sweet orange + 'Indian Red' pummelo and 'Hamlin' sweet orange + 'Singapura' pummelo were confirmed by leaf morphology, chromosome counting and molecular analysis. These hybrids have potential to be used directly as rootstocks aiming blight, citrus tristeza virus, and Phytophthora-induced disease tolerance, as well as for rootstocks improvement programs.O objetivo deste trabalho foi produzir híbridos somáticos entre laranjas doces e toranjas. Após fusão de protoplastos embriogênicos de laranja doce com protoplastos derivados de mesófilo foliar de toranjas, plantas foram regeneradas por embriogênese somática e aclimatizadas em casa de vegetação. Os híbridos laranja 'Hamlin' + toranja 'Indian Red' e laranja 'Hamlin' + toranja 'Singapura' foram confirmados pela morfologia foliar, contagem do número de cromossomos e análise molecular. Esses híbridos apresentam potencial para serem testados como porta-enxertos tolerantes a declínio, tristeza e doenças causadas por Phytophthora, bem como em programas de melhoramento de porta-enxertos.

  16. Ethno medicinal values of Citrus genus: A review

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    Swapnil Y Chaudhari

    2016-01-01

    Full Text Available Fruits of Citrus genus play an important role as a dietary supplement and therapeutic assent as well since ages. The present review summarizes some such attributes of Citrus genus. Literature review was done through published works to gather information on nutritional and ethnic values, phytochemical and pharmacological properties of Citrus. Information about the plant and phytochemical constituents, pharmacological activities were collected from the published reports. The plant was found to possess significant analgesic, anti-inflammatory, antioxidant, anthelmintic, antibacterial, antifungal, and hypolipidemic properties. They are found to be significant antihyperglycemic, antidiabetic, and hypoglycemic activity. The phytoconstituents which are present in the plant are mainly coumarins and flavonoids which are responsible for the actions. The phytochemical constituents and isolated bioactive compounds of Citrus can be investigated further to develop novel herbal drugs by using reverse pharmacological approaches especially in the treatment of liver diseases, arthritis, malignancies, and other inflammatory diseases.

  17. ÁCIDO GIBERÉLICO E O DESENVOLVIMENTO DE PLÂNTULAS DE TANGERINA 'CLEÓPATRA' (Citrus reshni hort. ex. Tanaka GIBBERELLIC ACID AND THE DEVELOPMENT OF MANDARIN (Citrus reshni hort. ex. Tanaka SEEDLINGS

    Directory of Open Access Journals (Sweden)

    Júnior Cesar Modesto

    1999-01-01

    Full Text Available Plântulas de tangerina 'Cleópatra'(Citrus reshni hort. ex. Tanaka, foram utilizadas em delineamento inteiramente casualizado, com três repetições no esquema de parcelas sub-divididas, onde os tratamentos principais foram 5 concentrações de ácido giberélico: T1 = 0, T2 = 25, T3 = 50, T4 = 100 e T5 = 150 mg.L-1, parceladas em quatro pulverizações. As coletas de material foram realizadas dos 70 aos 210 dias, em intervalos de 14 dias. Pelos resultados obtidos, o fitorregulador promoveu efeito favorável com relação ao incremento do comprimento do caule, sendo que aplicações de 100 e 150 mg.L-1 foram superiores as demais. O diâmetro do caule não foi influenciado pela aplicação de ácido giberélico.'Cleópatra' mandarin (Citrus reshni hort. ex. Tanaka seedlings used in an entirely randomized trial, with three replicates in a split plot format, were submitted to five gibberellic acid treatments of concentrations 0; 25; 50; 100; 150 mg.L-1, split into four sprayings. Data was collected, from the 70th up to the 120th day, in 14- day intervals. The results showed that the plant regulator enhanced the growth of the seedlings increasing the length of their stems. The sprays of concentration 100 and 150 mg.L-1 gave the best results. The gibberellic acid spraying had no effect on stem diameter.

  18. Effects of 15N application frequency on nitrogen uptake efficiency in citrus trees.

    Science.gov (United States)

    Quiñones, Ana; Bañuls, Josefina; Millo, Eduardo Primo; Legaz, Francisco

    2003-12-01

    Two irrigation systems were used to compare nitrogen uptake efficiency in citrus trees and to evaluate the NO3- runoff in "Navelina" orange trees [Citrus sinensis (L.) Osbeck] on Carrizo citrange rootstock (Citrus sinensis x Poncirus trifoliata Raf.). These were fertilized with 125 g N as labelled K15NO3 and grown outdoors in containers filled with a sand-loamy soil. Two groups of 3 trees received this N dose either in five equally split applications by a flooding irrigation system or in 66 applications by drip. Trees were harvested at the end of the vegetative cycle (December) and the isotopic ratios of 15N/14N were measured in the soil-plant system. The N uptake efficiency of the whole tree was higher with drip irrigation (75%) than with flooding system (64%). In the 0-90 cm soil profile, the N immobilized in the organic fraction was similar for both irrigation methods (around 13 %), whereas the N retained as NO3- was 1% of the N applied under drip and 10% under flooding. In the last case, most of NO3- remained under root system and it could be lost to leaching either by heavy rainfalls or excessive water applications. These results showed that a drip irrigation system was more efficient for improving water use and N uptake from fertilizer, in addition to potentially reduced leaching losses.

  19. Embriogénesis somática de Citrus macrophylla Wester con el empleo del Pectimorf® y análogos de brasinoesteroides

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    Lourdes Bao Fundora

    2013-06-01

    Full Text Available Título en ingles: Somatic embryogenesis of Citrus macrophylla Wester using Pectimorf® and analogues of brassinosteroids Resumen Los cítricos son frutales muy utilizados como patrones de injerto. Para incrementar la cantidad de estos cultivos en las plantaciones citrícolas, se pueden usar técnicas de propagación in vitro como la embriogénesis somática, que requiere medios de cultivos artificiales y fitohormonas. Debido a los altos costos de las fitohormonas, una alternativa cubana es el uso de biorreguladores del crecimiento de producción nacional como: los análogos de brasinoesteroides: 25(R 2α, 3α, dihidroxi 5α espirostan- 6-ona (Biobras-6 y C: 25(R 2α, 3α, 5α, trihidroxiespirostan-6-ona (MH-5 y una mezcla de oligogalacturónido de grado de polimerización entre 10-14 (Pectimorf®.  Estos biorreguladores son efectivos en los procesos morfogenéticos como sustitutos o complemento de las auxinas y citoquininas. El presente trabajo estuvo dirigido a determinar el efecto del Pectimorf® y los brasinoesteroides como sustitutos de las fitohormonas tradicionales en el desarrollo de la embriogénesis somática y en la obtención de una línea celular embriogénica de Citrus macrophylla Wester. Se utilizó el medio de cultivo de Murashige y Skoog (MS (1962, suplementado con los biorreguladores del crecimiento MH-5, Biobras-6 y Pectimorf®. Mediante la embriogénesis somática se obtuvieron embriones, raíces y plántulas, en todos los tratamientos. En la formación de plántulas estos biorreguladores fueron muy efectivos. Palabras clave: cultivo in vitro; Citrus; biorreguladores del crecimiento. Abstract Citrus fruits are widely used as rootstock. To increase the amount of these crops in plantations, in vitro propagation techniques such as somatic embryogenesis can be used, which requires artificial culture media and plant hormones. Due to the high cost of the plant hormone, a Cuban alternative is the use of cuban bioregulators growth

  20. Citrus orchard planted with no tillage and conventional systemsHuerto de cítricos plantado con sistema de cero labranza y sistema convencional

    Directory of Open Access Journals (Sweden)

    Carmen Silvia Vieira Janeiro Neves

    2010-02-01

    Full Text Available No tillage system has brought many advantages to soil protection, without reducing the yield of annual crops. This system has been adapted for Citrus orchards, with the plantation of trees in furrows opened in areas previously occupied by pastures. This work had as objective to evaluate tree development, root system, yield, and soil characteristics in an orchard planted in two systems. The study was made in Parana State, Brazil, in a medium texture oxisol with ‘Valência’ orange (Citrus sinensis L. trees with Rangpur lime rootstock (Citrus limonia Osbeck. The treatments were no tillage (furrowing and plantation and conventional plantation (hole area plowing and disk harrowing before furrowing and plantation. The yield was 86 - 129 kg of fruits per plant, without significant difference between treatments. The plantation systems either do not affect the development of the plants, the amount of roots and the fruit quality. In the conventional plantation system the soil has greater resistance to penetration in inter rows than in the zero tillage system plantation.El sistema de cero labranza ha traído muchas ventajas en la protección del suelo, sin perjudicar el rendimiento de los cultivos anuales. Este sistema ha sido adaptado para los huertos citrícolas, realizándose la plantación en surcos abiertos en terrenos anteriormente ocupados por pastizales. El trabajo tuvo como objetivo evaluar el desarrollo de las plantas y del sistema radicular, producción, características del suelo en un huerto plantado en dos sistemas de labranza. El estudio fue realizado en el Noroeste de Paraná, en un oxisol con textura media, en plantas de naranja ‘Valência’ con patrón de lima Rangpur. Los tratamientos evaluados fueron: cero labranza (apertura de surcos y plantación y plantación convencional (arado de discos y grada, seguido de apertura de surcos y plantación. La producción fue de 86 a 129 kg de frutos por planta, sin diferencia significativa

  1. Authenticity analysis of citrus essential oils by HPLC-UV-MS on oxygenated heterocyclic components

    Directory of Open Access Journals (Sweden)

    Hao Fan

    2015-03-01

    Full Text Available Citrus essential oils are widely applied in food industry as the backbone of citrus flavors. Unfortunately, due to relatively simple chemical composition and tremendous price differences among citrus species, adulteration has been plaguing the industry since its inception. Skilled blenders are capable of making blends that are almost indistinguishable from authentic oils through conventional gas chromatography analysis. A reversed-phase high performance liquid chromatography (HPLC method was developed for compositional study of nonvolatile constituents in essential oils from major citrus species. The nonvolatile oxygenated heterocyclic components identified in citrus oils were proved to be more effective as markers in adulteration detection than the volatile components. Authors are hoping such an analysis procedure can be served as a routine quality control test for authenticity evaluation in citrus essential oils.

  2. Construction and Evaluation of the Theoretical Model of Citrus Cooperative Organization

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the general overview of cooperative economic organizations of citrus industry at home and abroad,theoretical model of the modernization,industrialization and marketization of Citrus Cooperative Organization is established.After selecting the indices,such as the scale of production,the scale of management,the rate of encouraged farmers,and the market competitiveness,quantitative evaluation index system for modernization,industrialization and marketization is established.Then,Citrus Cooperative Organization is divided into three stages,such as primary stage,intermediate stage and senior stage.After evaluating the modernization,industrialization and marketization of citrus industry in the United States,Spain and South Africa,it is pointed out that the Citrus Cooperative Organization in China at present is at the primary stage.Finally,policy direction of the development of Citrus Cooperative Organization in China is pointed out.

  3. The vigour of glasshouse roses. Scion rootstock relationships, effects of phenotypic & genotypic variation.

    NARCIS (Netherlands)

    Vries, de D.P.

    1993-01-01

    Glasshouse roses commonly are combination plants, consisting of a scion variety and a rootstock of different genotypes. In this study, various environmental and genotypic factors have been investigated that influence the vigour of rootstocks and scion varieties, separately and in graft combination.I

  4. Naturalised Vitis rootstocks in Europe and consequences to native wild grapevine.

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    Nils Arrigo

    Full Text Available The genus Vitis is represented by several coexisting species in Europe. Our study focuses on naturalised rootstocks that originate in viticulture. The consequences of their presence to the landscape and to native European species (Vitis vinifera ssp. silvestris are evaluated. This study compares ecological traits (seven qualitative and quantitative descriptors and the genetic diversity (10 SSR markers of populations of naturalised rootstocks and native wild grapevines. 18 large naturalised rootstock populations were studied in the Rhône watershed. Wild European grapevines are present in four main habitats (screes, alluvial forests, hedges, and streamside hedges. In contrast, naturalised rootstock populations are mainly located in alluvial forests, but they clearly take advantage of alluvial system dynamics and connectivity at the landscape level. These latter populations appear to reproduce sexually, and show a higher genetic diversity than Vitis vinifera ssp. silvestris. The regrouping of naturalised rootstocks in interconnected populations tends to create active hybrid swarms of rootstocks. The rootstocks show characters of invasive plants. The spread of naturalised rootstocks in the environment, the acceleration of the decline of the European wild grapevine, and the propagation of genes of viticultural interest in natural populations are potential consequences that should be kept in mind when undertaking appropriate management measures.

  5. First report of root rot caused by Phytopythium helicoides on pistachio rootstock in California

    Science.gov (United States)

    We examined pathogenicity of Phytopythium helicoides on UCB-1 rootstock to investigate its role in root disease and collapse observed on potted pistachio plants. Approximately 25 potted 2-year-old pistachio rootstock trees in a Kern County, CA, research plot maintained outdoors and irrigated to cont...

  6. Evaluation of pyrus and quince rootstocks for high density pear orchards

    NARCIS (Netherlands)

    Maas, F.M.

    2008-01-01

    High density planting systems are a prerequisite to economise the use of land and labour costs of orchards. Dwarfing rootstocks controlling the vigour of the scion cultivars form the basis for such orchards (Wertheim and Webster, 2005). In the Netherlands, rootstock research is limited to and focuss

  7. Rootstock of interspecific squash hybrids (Cucurbita maxima x Cucurbita moschata) increases lycopene content of watermelon

    Science.gov (United States)

    The watermelon industry in the U.S. is facing increased soil-borne disease pressure and the loss of the soil fumigant methyl bromide. To combat this, grafting of scions with disease-resistant rootstocks of cucurbit species has garnered widespread interest. Both scion and rootstock can affect plant...

  8. Phylogenetic Relationships Among Cucurbit Species Used as Rootstocks for Grafting Watermelon

    Science.gov (United States)

    There is an increased interest in the United States in grafting watermelon on cucurbit rootstocks to control soilborne diseases. Several cucurbit species including Lagenaria siceraria, Cucurbita spp. and Benincasa hispida (wax gourds) have been used in Asia as rootstocks for watermelon. In our pre...

  9. Improved watermelon quality using bottle gourd rootstock expressing a Ca(2+)/H(+) antiporter

    Science.gov (United States)

    Bottle gourd ("Lagenaria siceraria" Standl.) has been commonly used as a source of rootstock for watermelon. To improve its performance as a rootstock without adverse effects on the scion, the bottle gourd was genetically engineered using a modified "Arabidopsis" Ca(2+)/H(+) exchanger sCAX2B. This t...

  10. Mudas de laranjeira 'valência' sobre dois porta-enxertos e sob diferentes manejos de adubação 'Valencia' sweet orange nursery trees on two rootstocks under different fertilizer managements

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    Eduardo Augusto Girardi

    2010-09-01

    Full Text Available O manejo da adubação é uma das principais práticas culturais para a produção de mudas cítricas em cultivo protegido. Avaliou-se o efeito de seis tipos de manejo das adubações comercialmente recomendadas na produção de mudas de laranjeira 'Valência' [Citrus sinensis (L. Osbeck] enxertada sobre os porta-enxertos limoeiro 'Cravo' (Citrus limonia Osbeck e citrumeleiro 'Swingle' [Citrus paradisi Macf. x Poncirus trifoliata (L. Raf.]. As avaliações foram conduzidas a partir da transplantação dos porta-enxertos até 180 dias após a enxertia, em viveiro empresarial, em Conchal-SP. Os manejos corresponderam a duas soluções de fertilizantes solúveis aplicadas isoladamente, soluções de fertilizante solúveis associadas a fertilizante de liberação controlada e aplicação exclusiva de fertilizante de liberação controlada. O delineamento experimental adotado foi o fatorial 2 x 6 (porta-enxerto x manejo da adubação, em blocos casualizados, com três repetições e 12 mudas na parcela. O limoeiro 'Cravo' induziu maior crescimento ao enxerto. O crescimento vegetativo das mudas foi similar após o uso de fertilizantes solúveis ou de liberação controlada, apesar da grande variação de quantidades totais de nutrientes fornecidas às plantas. Desta forma, o viveirista poderá optar pelo manejo mais econômico ou prático, conforme as condições locais.The fertilizer program is a major practice for screened citrus nursery tree production. The effect of six fertilizer programs commercially recommended was evaluated on the production of 'Valência' sweet orange [Citrus sinensis (L. Osbeck] nursery trees budded on rootstocks 'Rangpur' lime (Citrus limonia Osbeck and 'Swingle' citrumelo [Citrus paradisi Macf. x Poncirus trifoliata (L. Raf.]. Experimental work was carried out from rootstock transplant until 180 days after budding, in a citrus nursery in Conchal, SP, Brazil. Fertilizer managements consisted of two soluble fertilizers

  11. Molecular characterization of Prunus mahaleb L. rootstock canditates by ISSR markers

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    Ozyurt Ibrahim Kursat

    2013-01-01

    Full Text Available Prunus mahaleb is widely used as rootstocks particularly on calcareous and dry soils for both sweet and sour cherry cultivars in Turkey. Genetic diversity and relationships among members of Prunus mahaleb including 29 preselected rootstock candidate accessions from Tokat region in Turkey were investigated by using 15 ISSR markers. The study revealed high genetic diversity among accessions, detecting 138 fragments, of which 103 (75% were polymorphic. The number of polymorphic bands per primer was between 3-13, with average of 6.86. The primers 890 and 891 gave the highest polymorphism ratio (100%. The UPGMA dendrogram and the principal coordinate analysis revealed a clear differentiation among accessions. Reference rootstock, SL-64 clustered separately. The study demonstrates that ISSRs provide promising marker tools in revealing genetic diversity and relationships in Prunus mahaleb rootstock candidate accessions and can contribute to efficient identification, conservation, and utilization of germplasm for rootstock improvement through conventional as well as molecular breeding approaches.

  12. 76 FR 8603 - Citrus Seed Imports; Citrus Greening and Citrus Variegated Chlorosis

    Science.gov (United States)

    2011-02-15

    ... propagative seed of several Rutaceae (citrus family) genera from certain countries where citrus greening or... Rutaceae may be a pathway for the introduction of those diseases. The interim rule was necessary in order...), we amended the regulations to prohibit the importation of propagative seed of several...

  13. Desenvolvimento vegetativo, produção e qualidade de frutos da tangerina 'Fremont' sobre quatro porta-enxertos Growth, yield and fruit quality of 'Fremont' mandarin on four rootstocks

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    Erick Espinoza Núñez

    2007-08-01

    Full Text Available Com o objetivo de avaliar o desenvolvimento vegetativo, produção e qualidade de frutos da tangerina 'Fremont' (C. clementina Hort. ex Tan. X C. reticulata Blanco sobre os porta-enxertos limão 'Cravo' (C. limonia Osbeck, citrumelo 'Swingle' (P. trifoliata Raf. x C. paradisi Macf., tangerina 'Cleópatra' (Citrus reshni Hort. ex Tan. e tangelo 'Orlando' (C. reticulata Blanco x C. paradisi Macf., foi instalado um experimento em Bebedouro-SP, em 1997. Embora diferenças na produção tenham sido registradas em função dos porta-enxertos, nos anos de 2003 a 2005, a produção acumulada nas safras de 2000 a 2006 não revelou influência dos mesmos. Os valores do índice de alternância de produção e eficiência de produção não foram influenciados pelos porta-enxertos. O teor de sólidos solúveis, bem como acidez total foram superiores nos frutos das plantas enxertadas sobre citrumelo 'Swingle' e tangerina 'Cleópatra'. Os valores de volume da copa e diâmetro do tronco foram superiores nas árvores sobre tangelo 'Orlando' e tangerina 'Cleópatra'.An experiment was installed in Bebedouro, SP, Brazil in 1997, with the aim of evaluate the effect of the rootstocks 'Rangpur' lime (C. limonia Osbeck, 'Swingle' citrumelo (P. trifoliata Raf. x C. paradisi Macf., 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan. and 'Orlando' tangelo (C. reticulata Blanco x C. paradisi Macf. on plant growth, yield and fruit quality of 'Fremont' mandarin (C. clementina Hort. ex Tan. X C. reticulata Blanco. Despite that differences in yield have been registered related to the rootstocks between 2003 to 2005; cumulative yield from 2000 to 2006 seasons was not affected by the rootstock. Alternate bearing index and yield efficiency values were not influenced by the rootstocks. Fruits from trees on 'Swingle' citrumelo and 'Cleópatra' mandarin had higher values of total soluble solids concentration and total acids. Trunk diameter and canopy volume values were higher in

  14. Comportamento de 16 porta-enxertos para o tangor Murcott na região de Itirapina-SP Behavior of sixteen rootstocks for Murcott in Itirapina, SP, Brazil

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    José Orlando de Figueiredo

    2006-04-01

    Full Text Available Foi monitorado o comportamento de 16 porta-enxertos para o tangor Murcott [Citrus reticulata Blanco x C. sinensis (L. Osbeck], do clone nucelar J, em experimento instalado em 1990, na Fazenda Raio de Sol, Itirapina-SP. Os porta-enxertos foram: tangelo 'Orlando' (C. reticulata Blanco x C. paradisi Macf., laranja 'Caipira DAC' [C. sinensis (L. Osbeck], limão 'Cravo'(C. limonia Osbeck, os trifoliatas 'Kryder 8-5'e 'EEL'[Poncirus trifoliata (L. Raf.] e as tangerinas 'Cleópatra' (C. reshni hort. ex. Tanaka, 'Sunki' [C. sunki (Hayata hort. ex. Tanaka], 'Batangas', 'Oneco', 'Swatow', 'Szinkon', 'Satsuma', 'Cravo', 'Dancy', 'Suen Kat' e 'Pook Ling Ming' (C. reticulata Blanco. As produções foram avaliadas de 1996 a 2003 e as maiores médias foram proporcionadas pelas plantas enxertadas nas tangerinas 'Cleópatra', 'Suen Kat', 'Pook Ling Ming' e 'Sunki' (>40 kg planta-1. Dentre os porta-enxetos que induziram as mais baixas produções, estão os dois trifoliatas, a 'Caipira DAC' e a tangerina 'Cravo' (Sixteen rootstocks were compared in a trial started in 1990, for Murcott tangor, nucellar clone "J", in Itirapina, Brazil. The rootstocks tested were Orlando tangelo (Citrus reticulata Blanco x C. paradisi Macf., sweet orange [C. sinensis (L. Osbeck] cv. Caipira DAC, Rangpur lime (C. limonia Osbeck, Poncirus trifoliata (L. Raf. cv. Kryder 8-5, P. trifoliata (L. Raf. cv. EEL and the mandarins Cleopatra (C. reshni hort. ex. Tanaka, Sunki [C. sunki (Hayata hort. ex. Tanaka] and Batangas, Oneco, Swatow, Szinkon, Satsuma, Cravo, Dancy, Suen Kat and Pook Ling Ming (C. reticulata Blanco. Fruit yield was measured per plant, in a period of seven years (1996-2003. The best yielding rootstocks were Cleopatra, Suen Kat, Pook Ling Ming and Sunki mandarins (> 40 kg tree-1. The two Trifoliate, sweet orange cv. Caipira DAC and Cravo mandarin presented the lowest yields (< 25 kg tree-1. No significant variation was observed for fruit quality characteristics of trees on

  15. Qualidade industrial e maturação de frutos de laranjeira "valência" sobre seis porta-enxertos Industrial quality and maturation of fruits of 'valência' sweet orange trees on six rootstocks

    Directory of Open Access Journals (Sweden)

    Pedro Antonio Martins Auler

    2009-12-01

    Full Text Available Com o objetivo de avaliar a influência de seis porta-enxertos sobre a maturação e as características físico-químicas de frutos de laranjeira 'Valência', instalou-se um experimento em janeiro de 1994, no município de Nova Esperança-PR. O delineamento experimental foi de blocos ao acaso, com quatro repetições, três plantas úteis por parcela e seis tratamentos, constituídos pelos porta-enxertos: limoeiro 'Cravo' (Citrus limonia, tangerineiras 'Cleópatra' (C. reshni e 'Sunki' (C. sunki, citrangeiro 'Troyer' (Poncirus trifoliata x C. sinensis, tangeleiro 'orlando' (C. tangerina x C. paradisi e laranjeira 'Caipira'(C. sinensis. Avaliou-se a qualidade dos frutos em sete safras e a curva de maturação foi estimada para os anos de 1999 e 2000. Todos os porta-enxertos proporcionaram qualidade aceitável aos frutos da laranjeira 'Valência', com destaque para o citrangeiro 'Troyer' que superou o limoeiro 'Cravo' em rendimento industrial. Em um ano considerado com padrão climático normal, a evolução do índice tecnológico ajustou-se a uma equação de regressão quadrática, proporcionando melhor rendimento industrial quando os frutos foram colhidos no início de novembro, independentemente do porta-enxerto utilizado.In order to evaluate the influence of six rootstocks on the maturation and the physical characteristics and chemical composition of 'Valência' fruits, a research was conducted in a field established in 1994, in Nova Esperança city, state of Paraná, Brazil. A complete randomized block design was used, with four replications, three evaluated trees per plot and six treatments, constituted by the rootstocks: 'Rangpur' lime (Citrus limonia, 'Cleopatra' (C. reshni and 'Sunki' (C. sunki mandarins, 'Troyer' citrange (Poncirus trifoliata x C. sinensis, 'orlando' tangelo (C. tangerina x C. paradisi and 'Caipira' sweet orange (C. sinensis. Fruit quality was evaluated along seven harvesting seasons and the maturation curve was

  16. Rapid Propagation of Sweet and Sour Cherry Rootstocks

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    Dušica DORIĆ

    2014-12-01

    Full Text Available The paper presents a protocol for micropropagation of Prunus sp. rootstocks included in the sweet and sour cherry breeding program. Germplasm diversity for rootstock breeding derives from natural populations, where conditions and biological vectors for systematic infection with viral diseases are constantly present. The establishment of aseptic culture depends primarily on the explant type, as all selections were collected from natural habitat. For nearly all investigated selections, dormant buds were the favored source, due to enabling rosette initiation in more than 58% cases. In P. cerasus L. selections, 100% contamination was noted when shoot tips were used as an explant source. Significant influence of the double-phase medium on the number and height of multiplied shoots was observed in the standard cherry rootstock, ‘Gisela 6’. For P. fruticosa Pall., selection ‘SV1’ and ‘SV2’, and P. cerasus ‘D6’ selection, the double-phase medium also had a significant effect on the height of multiplied shoots, when compared to solid DKW (Driver and Kuniyuki Walnut medium. Genetic variability of selections within the investigated species resulted in variable plant rooting success. Adding Fe-EDDHA (Ethylenediamine di-2-hydroxy-phenyl acetate ferric in the 200 mg l-1 concentration to the rooting medium significantly enhanced the percentage of rooted plants. The highest rooting percentage was noted for ‘Gisela 6’ and ‘D6’ genotype at 1 mg l-1 IBA (indole-3-butyric acid, while 0.8 mg l-1 was the optimum concentration for P. mahaleb L. ‘M1’ selection. P. fruticosa genotypes required significantly higher IBA concentration for rooting (2.5 and 3.5 mg l-1.

  17. Involvement of an ethylene response factor in chlorophyll degradation during citrus fruit degreening

    Science.gov (United States)

    Chlorophyll degradation naturally occurs during plant senescence. However, in fruit such as citrus, it is a positive characteristic, as degreening is an important colour development contributing to fruit quality. In the present work, Citrus sinensis Osbeck, cv. Newhall fruit was used as a model for ...

  18. Tetraploidy Enhances Boron-Excess Tolerance in Carrizo Citrange (Citrus sinensis L. Osb. × Poncirus trifoliata L. Raf.)

    Science.gov (United States)

    Ruiz, Marta; Quiñones, Ana; Martínez-Alcántara, Belén; Aleza, Pablo; Morillon, Raphaël; Navarro, Luis; Primo-Millo, Eduardo; Martínez-Cuenca, Mary-Rus

    2016-01-01

    Tetraploidy modifies root anatomy which may lead to differentiated capacity to uptake and transport mineral elements. This work provides insights into physiological and molecular characters involved in boron (B) toxicity responses in diploid (2x) and tetraploid (4x) plants of Carrizo citrange (Citrus sinensis L. Osb. × Poncirus trifoliata L. Raf.), a widely used citrus rootstock. With B excess, 2x plants accumulated more B in leaves than 4x plants, which accounted for their higher B uptake and root-to-shoot transport rates. Ploidy did not modify the expression of membrane transporters NIP5 and BOR1 in roots. The cellular allocation of B excess differed between ploidy levels in the soluble fraction, which was lower in 4x leaves, while cell wall-linked B was similar in 2x and 4x genotypes. This correlates with the increased damage and stunted growth recorded in the 2x plants. The 4x roots were found to have fewer root tips, shorter specific root length, longer diameter, thicker exodermis and earlier tissue maturation in root tips, where the Casparian strip was detected at a shorter distance from the root apex than in the 2x roots. The results presented herein suggest that the root anatomical characters of the 4x plants play a key role in their lower B uptake capacity and root-to-shoot transport. Highlights Tetraploidy enhances B excess tolerance in citrange Carrizo Expression of NIP5 and BOR1 transporters and cell wall-bounded B are similar between ploidies B tolerance is attributed to root anatomical modifications induced by genome duplication The rootstock 4x citrange carrizo may prevent citrus trees from B excess. PMID:27252717

  19. Citrus tristeza virus-based RNAi in citrus plants induces gene silencing in Diaphorina citri, a phloem-sap sucking insect vector of citrus greening disease (Huanglongbing).

    Science.gov (United States)

    Hajeri, Subhas; Killiny, Nabil; El-Mohtar, Choaa; Dawson, William O; Gowda, Siddarame

    2014-04-20

    A transient expression vector based on Citrus tristeza virus (CTV) is unusually stable. Because of its stability it is being considered for use in the field to control Huanglongbing (HLB), which is caused by Candidatus Liberibacter asiaticus (CLas) and vectored by Asian citrus psyllid, Diaphorina citri. In the absence of effective control strategies for CLas, emphasis has been on control of D. citri. Coincident cohabitation in phloem tissue by CLas, D. citri and CTV was exploited to develop a novel method to mitigate HLB through RNA interference (RNAi). Since CTV has three RNA silencing suppressors, it was not known if CTV-based vector could induce RNAi in citrus. Yet, expression of sequences targeting citrus phytoene desaturase gene by CTV-RNAi resulted in photo-bleaching phenotype. CTV-RNAi vector, engineered with truncated abnormal wing disc (Awd) gene of D. citri, induced altered Awd expression when silencing triggers ingested by feeding D. citri nymphs. Decreased Awd in nymphs resulted in malformed-wing phenotype in adults and increased adult mortality. This impaired ability of D. citri to fly would potentially limit the successful vectoring of CLas bacteria between citrus trees in the grove. CTV-RNAi vector would be relevant for fast-track screening of candidate sequences for RNAi-mediated pest control.

  20. Genome-scale mRNA and small RNA transcriptomic insights into initiation of citrus apomixis

    Science.gov (United States)

    Long, Jian-Mei; Liu, Zheng; Wu, Xiao-Meng; Fang, Yan-Ni; Jia, Hui-Hui; Xie, Zong-Zhou; Deng, Xiu-Xin; Guo, Wen-Wu

    2016-01-01

    Nucellar embryony (NE) is an adventitious form of apomixis common in citrus, wherein asexual embryos initiate directly from nucellar cells surrounding the embryo sac. NE enables the fixation of desirable agronomic traits and the production of clonal offspring of virus-free rootstock, but impedes progress in hybrid breeding. In spite of the great importance of NE in citrus breeding and commercial production, little is understood about the underlying molecular mechanisms. In this study, the stages of nucellar embryo initiation (NEI) were determined for two polyembryonic citrus cultivars via histological observation. To explore the genes and regulatory pathways involved in NEI, we performed mRNA-seq and sRNA-seq analyses of ovules immediately prior to and at stages during NEI in the two pairs of cultivars. A total of 305 differentially expressed genes (DEGs) were identified between the poly- and monoembryonic ovules. Gene ontology (GO) analysis revealed that several processes are significantly enriched based on DEGs. In particular, response to stress, and especially response to oxidative stress, was over-represented in polyembryonic ovules. Nearly 150 miRNAs, comprising ~90 conserved and ~60 novel miRNAs, were identified in the ovules of either cultivar pair. Only two differentially expressed miRNAs (DEMs) were identified, of which the novel miRN23-5p was repressed whereas the targets accumulated in the polyembryonic ovules. This integrated study on the transcriptional and post-transcriptional regulatory profiles between poly- and monoembryonic citrus ovules provides new insights into the mechanism of NE, which should contribute to revealing the regulatory mechanisms of plant apomixis. PMID:27619233

  1. Alteração na atividade de peroxidase e concentração de fenóis em microtangerinas (Citrus spp. infectadas por Phytophthora parasitica

    Directory of Open Access Journals (Sweden)

    José Ribamar Gusmão Araújo

    2008-02-01

    Full Text Available The present research aimed to characterize and evaluate species and varieties of small-fruited mandarins of Tanaka’s group (Citrus spp. with potential use as rootstocks, in relation to infection to the Phytophthora parasitica, by means of foliar determination of peroxidase activity and total phenolics content. It was used the following species: C. reshni Hort. ex Tan., C. sunki Hort. ex Tan., C. pectinifera Tan., C. crenatifolia Lush., C. amblycarpa Ochese, C. aurantium L, C. reticulata Blanco and C. limonia Osb. The Center of Citrus Germoplasm of Botucatu and Cordeirópolis provide all plant material. Four resistant varieties to the stem rot and root rot infections: Pectinifera, Crenatifolia, Sun Chu Shu (clone Kat 1004 and Cleopatra (clone 1 were evaluated. Susceptible plants infected by P. parasitica presented higher activity of peroxidase, while phenolics contents were lower in susceptible group.

  2. Overexpression of a modified plant thionin enhances disease resistance to citrus canker and Huanglongbing (HLB

    Directory of Open Access Journals (Sweden)

    Guixia Hao

    2016-07-01

    Full Text Available Huanglongbing (HLB or citrus greening disease caused by Candidatus Liberibacter asiaticus (Las is a great threat to the US citrus industry. There are no proven strategies to eliminate HLB disease and no cultivar has been identified with strong HLB resistance. Citrus canker is also an economically important disease associated with a bacterial pathogen (Xanthomonas citri. In this study, we characterized endogenous citrus thionins and investigated their expression in different citrus tissues. Since no HLB-resistant citrus cultivars have been identified, we attempted to develop citrus resistant to both HLB and citrus canker through overexpression of a modified plant thionin. To improve effectiveness for disease resistance, we modified and synthesized the sequence encoding a plant thionin and cloned into the binary vector pBinPlus/ARS. The construct was then introduced into Agrobacterium strain EHA105 for citrus transformation. Transgenic Carrizo plants expressing the modified plant thionin were generated by Agrobacterium-mediated transformation. Successful transformation and transgene gene expression was confirmed by molecular analysis. Transgenic Carrizo plants expressing the modified thionin gene were challenged with X. citri 3213 at a range of concentrations, and a significant reduction in canker symptoms and a decrease in bacterial growth were demonstrated compared to nontransgenic plants. Furthermore the transgenic citrus plants were challenged with HLB via graft inoculation. Our results showed significant Las titer reduction in roots of transgenic Carrizo compared with control plants and reduced scion Las titer twelve months after graft inoculation. These data provide promise for engineering citrus disease resistance against HLB and canker.

  3. Polyembryony in non-apomictic citrus genotypes

    Science.gov (United States)

    Aleza, Pablo; Juárez, José; Ollitrault, Patrick; Navarro, Luis

    2010-01-01

    Background and Aims Adventitious embryony from nucellar cells is the mechanism leading to apomixis in Citrus sp. However, singular cases of polyembryony have been reported in non-apomictic genotypes as a consequence of 2x × 4x hybridizations and in vitro culture of isolated nucelli. The origin of the plants arising from the aforementioned processes remains unclear. Methods The genetic structure (ploidy and allelic constitution with microsatellite markers) of plants obtained from polyembryonic seeds arising from 2x × 4x sexual hybridizations and those regenerated from nucellus culture in vitro was systematically analysed in different non-apomictic citrus genotypes. Histological studies were also conducted to try to identify the initiation process underlying polyembryony. Key Results All plants obtained from the same undeveloped seed in 2x × 4x hybridizations resulted from cleavage of the original zygotic embryo. Also, the plants obtained from in vitro nucellus culture were recovered by somatic embryogenesis from cells that shared the same genotype as the zygotic embryos of the same seed. Conclusions It appears that in non-apomictic citrus genotypes, proembryos or embryogenic cells are formed by cleavage of the zygotic embryos and that the development of these adventitious embryos, normally hampered, can take place in vivo or in vitro as a result of two different mechanisms that prevent the dominance of the initial zygotic embryo. PMID:20675656

  4. Nitrogênio, fósforo e potássio na nutrição e no crescimento de mudas de laranjeiravalência, enxertadas sobre limoeiro cravo Effect of nitrogen, phosphorus, and potassium levels on nutrition and production of seedlings of 'Valencia' sweet orange grafted on 'cravo' lemon rootstock

    Directory of Open Access Journals (Sweden)

    Renato de Mello Prado

    2009-12-01

    Full Text Available O experimento foi conduzido em casa de vegetação telada na FCAV/Unesp campus Jaboticabal-SP, durante o período de novembro de 2005 a janeiro de 2007. Conduziu-se este estudo, com o objetivo de avaliar componentes do desenvolvimento e do estado nutricional de mudas de laranjeira Valência (Citrus sinensis Osbeck, enxertadas sobre limoeiro Cravo (Citrus limonia Osbeck, em função de doses de nitrogênio, fósforo e potássio. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 3³ + 1, sendo 3 fatores (nitrogênio, fósforo e potássio - NPK, 3 doses e uma testemunha (sem adubação, com 3 repetições. A unidade experimental foi representada por uma muda de laranjeira por sacola com 5 dm³ com 2,5 kg de substrato casca de Pinus spp. e vermiculita. Os tratamentos foram constituídos pela metade, uma vez e duas vezes a dose padrão recomendada, de 4.590; 920 e 4.380 mg sacola-1, de N, P e K, respectivamente. As adubações com N e K foram realizadas via fertirrigações três vezes por semana e o P foi adicionado ao substrato antes do replantio das mudas. Aos 424 dias após o transplantio, as plantas foram subdivididas em raízes e parte aérea para determinação da massa da matéria seca, altura, área foliar, diâmetro do caule e conteúdo de nutrientes. A adubação com N, P e K proporcionou maior desenvolvimento e maior acúmulo desses macronutrientes na parte aérea e nas raízes das mudas de laranjeira Valência, sobre limoeiro Cravo. Houve adequado desenvolvimento das plantas com a metade da dose recomendada de N, P e K pela literatura, aproximadamente de 918, 184 e 876 mg dm-3, respectivamente.The experiment was carried out in greenhouse at the FCAV/Unesp, Jaboticabal-SP during the period of November 2005 to January 2007. The objective of this study was to evaluate development components and nutritional status of seedlings of 'Valencia' (Citrus sinensis Osbeck sweet orange grafted on 'Cravo' lemon rootstock

  5. 26 CFR 1.278-1 - Capital expenditures incurred in planting and developing citrus and almond groves.

    Science.gov (United States)

    2010-04-01

    ... or this section) which is attributable to the planting, cultivation, maintenance, or development of... regard to section 278 or this section) attributable to the planting, cultivation, maintenance, or... peel and pulpy flesh, such as the orange, grapefruit, lemon, lime, citron, tangelo, and tangerine....

  6. Etiology of three recent diseases of citrus in São Paulo State: sudden death, variegated chlorosis and huanglongbing.

    Science.gov (United States)

    Bové, Joseph Marie; Ayres, Antonio Juliano

    2007-01-01

    The state of São Paulo (SSP) is the first sweet orange growing region in the world. Yet, the SSP citrus industry has been, and still is, under constant attack from various diseases. In the 1940s, tristeza-quick decline (T-QD) was responsible for the death of 9 million trees in SSP. The causal agent was a new virus, citrus tristeza virus (CTV). The virus was efficiently spread by aphid vectors, and killed most of the trees grafted on sour orange rootstock. Control of the disease resided in replacing sour orange by alternative rootstocks giving tolerant combinations with scions such as sweet orange. Because of its drought resistance, Rangpur lime became the favourite alternative rootstock, and, by 1995, 85% of the SSP sweet orange trees were grafted on this rootstock. Therefore, when in 1999, many trees grafted on Rangpur lime started to decline and suddenly died, the spectre of T-QD seemed to hang over SSP again. By 2003, the total number of dead or affected trees was estimated to be over one million. The new disease, citrus sudden death (CSD), resembles T-QD in several aspects. The two diseases have almost the same symptoms, they spread in time and space in a manner strikingly similar, and the pathological anatomy of the bark at the bud union is alike. Transmission of the CSD agent by graft-inoculation has been obtained with budwood inoculum taken not only on CSD-affected trees (grafted on Rangpur lime), but also on symptomless trees (grafted on Cleopatra mandarin) from the same citrus block. This result shows that symptomless trees on Cleopatra mandarin are tolerant to the CSD agent. Trees on rootstocks such as Sunki mandarin or Swingle citrumelo are also tolerant. Thus, in the CSD-affected region, control consists in replacing Rangpur lime with compatible rootstocks, or in approach-grafting compatible rootstock seedlings to the scions of trees on Rangpur lime (inarching). More than 5 million trees have been inarched in this way. A new disease of sweet orange

  7. Effect of silicon-based fertilizer applications on the reproduction and development of the citrus mealybug (Hemiptera: Pseudococcidae) feeding on green coleus.

    Science.gov (United States)

    Hogendorp, Brian K; Cloyd, Raymond A; Swiader, John M

    2009-12-01

    Mealybugs are major insect pests of greenhouses, interiorscapes, and conservatories because they feed on a wide-range of horticultural crops. Furthermore, mealybugs are difficult to regulate with insecticides due to the presence of a nearly impervious protective waxy covering, which means that alternative management strategies are required. As such, this study, involving two replicated experiments, was designed to determine the value of applying silicon-based fertilizers, as potassium silicate, to coleus, Solenstemon scutellarioides (L.) Codd, plants as a way to prevent outbreaks of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae). The first experiment evaluated the effects of different application methods (foliar and drench), at 50 ppm silicon, using the commercially-available product, ProTek 0-0-3 The Silicon Solution. The second experiment entailed applying the silicon-based fertilizer as a drench to the growing medium at different rates (0, 100, 400, 800, and 1,600 ppm silicon). We determined the effects of the silicon-based fertilizer treatments on citrus mealybug life history parameters including number of eggs laid by the adult female, body size, and developmental time from first instar to ovipositing adult female. Furthermore, we used a plant alkaline fusion technique to assess the concentration (milligrams per kilogram or ppm) of silicon in the coleus plant tissues at variable time intervals (days). In general, this technique involved dry-ashing plant tissue in a muffle furnace, followed by alkaline fusion and then colormetric analysis. The silicon-based fertilizer application treatments, in both experiments, did not negatively affect any of the citrus mealybug life history parameters measured. In the first experiment, citrus mealybug female egg load ranged from 199.5 (drench application) to 219.4 (combination spray and drench application), and developmental time (days) from first instar crawler to ovipositing female ranged from

  8. Development of a control alternative for the citrus fruit borer, Ecdytolopha aurantiana (Lepidoptera, Tortricidae): from basic research to the grower

    Energy Technology Data Exchange (ETDEWEB)

    Parra, Jose Roberto P.; Bento, Jose Mauricio S. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola], e-mail: jrpparra@esalq.usp.br; Garcia, Mauro S. [Universidade Federal de Pelotas (UFPel), RS (Brazil); Yamamoto, Pedro T. [Fundo de Defesa da Citricultura (Fundecitrus), Araraquara, SP (Brazil); Vilela, Evaldo F. [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal; Leal, Walter S. [University of California, Davis, CA (Brazil). Dept. of Entomology

    2004-12-15

    All research steps, developed from 1995 to 2000, to synthesize the sex pheromone of Ecdytolopha aurantiana (Lima, 1927) are described, in order to monitoring this pest that causes losses in the order of 50 million dollars per year to citriculture in the State of Sao Paulo. The basic researches conducted are described, including the development of an artificial diet for the insect, the study of its temperature and humidity requirements, behavioral studies, and synthesis of the male-attracting substance up to the formulation and distribution of the pheromone to the grower, by means of its commercialization. It is a case of success, at a cost of 50 thousand dollars, involving inter- and multidisciplinary researches, which can be adopted to other insect pests in the country. (author)

  9. Comportamento do pessegueiro 'Granada' sobre diferentes porta-enxertos The behavior of peach tree 'Granada' on differents rootstocks

    Directory of Open Access Journals (Sweden)

    Andrea de Rossi

    2004-12-01

    Full Text Available O trabalho teve por objetivo avaliar o efeito dos porta-enxertos Aldrighi, Flordaguard, Hansen 2168, Okinawa, Pavia Moscatel, Tsukuba 1 e Umezeiro sobre o comportamento da cv. Granada, nas condições do Sul do Brasil. O trabalho foi desenvolvido na Faculdade de Agronomia Eliseu Maciel da Universidade Federal de Pelotas. Durante o período de execução do experimento, foram avaliados diâmetro do tronco, volume da copa, peso fresco do material vegetal retirado nas podas verde e de inverno, índice de intensidade de poda, data de plena floração, comprimento do período de floração, peso médio das frutas, produção por planta, produção estimada por hectare, eficiência produtiva, sólidos solúveis totais e firmeza de polpa das frutas. As avaliações permitiram concluir que os porta-enxertos mais vigorosos conferem maior diâmetro do tronco e volume de copa, bem como maior produção às plantas; a maior produção obtida nas plantas sobre porta-enxertos mais vigorosos não afeta o peso médio das frutas. Pela resistência a fitonematóides e o comportamento observado neste estudo, os porta-enxertos Tsukuba 1 e Okinawa podem ser indicados como porta-enxertos potenciais para a cultura do pessegueiro nas condições do Sul do Brasil.The objective of this experiment was to evaluate the effect of Aldrighi, Flordaguard, Hansen 2168, Okinawa, Pavia Moscatel, Tsukuba 1 and Umezeiro rootstocks on behavior of the cultivar Granada in the South of Brazil. The experiment was developed at "Faculdade de Agronomia Eliseu Maciel" of the "Universidade Federal de Pelotas". The parameters evaluated were trunk diameter, foliage size, pruning wood weight, pruning intesity index, full bloom date, bloom period, weight fruits, production per plant, estimed prodcution per hectare, yield efficiency, soluble solid content and fruit firmess. The results showed that vigorous roostocks resulted higher trunk diameter and foliage size and production; the higher

  10. Graft incompatibility in plants: Metabolic changes during formation and establishment of the rootstock/scion union with emphasis on Prunus species

    Directory of Open Access Journals (Sweden)

    Felipe Gainza

    2015-08-01

    Full Text Available Commercial fruit trees are usually formed by the combination of a rootstock and a scion to broaden the adaptability of scion cultivars to soil and climatic conditions, facilitate agricultural management, and/or increase productivity. In the different cultivated species of the genus Prunus, rootstocks having a wide range of uses are scarce, because of rootstock/ scion graft incompatibilities that prevent the establishment of a strong and lasting functional union. Graft incompatibility is a problem in cherry, almond, and apricot than in peach or plum. In general, closely related cultivars and species tend to be compatible, but taxonomically distant plants often manifest incompatibility. This review will focus on the knowledge currently available on the metabolic response during the formation and establishment of the stock/scion graft union in order to help the effort for identify future metabolic markers to be used in breeding programs. The physiological, metabolic and molecular mechanisms that cause incompatibility remain unclear and several hypotheses have been proposed to explain it, mostly based on herbaceous species. Few studies are available to explain incompatibility in woody plants. Various phenolic compounds are known to affect cell division, development and differentiation at the graft union. Flavonol (catechins and proanthocyanidins concentrations increase shortly after grafting and, as a result of the stress induced during the healing response, vacuolar membrane disruption occurs resulting in the escape of phenols from the vacuole into the cytoplasmic matrix, causing dysfunctions in the growth of certain tissues (xylem and phloem, interference with the synthesis of lignin or inducing hormonal imbalances. All these abnormalities result in mechanical weakening of the union, which may manifest during the first year after grafting (translocated incompatibility or may appear several years later (localized incompatibility, leading to major

  11. The Citrus Sanitation Center of Estación Experimental Agroindustrial Obispo Colombres, Tucumán, Argentina El Centro de Saneamiento de Citrus de la Estación Experimental Agroindustrial Obispo Colombres de Tucumán, Argentina

    Directory of Open Access Journals (Sweden)

    Beatriz E. Stein

    Full Text Available In October 2004, the Estación Experimental Agroindustrial Obispo Colombres (Tucumán, Argentina founded its Citrus Sanitation Center. The goal of this center is to establish and keep a group of the most important citrus varieties and rootstocks true to type and free of graft-transmissible pathogens. These will be used as primary sources of propagating material for citrus growers and researchers in northwestern Argentina. Mother trees of the main commercial citrus varieties were selected from the germplasm bank of the experiment station and were recovered through the standard procedure of shoot tip grafting (STG. Healthy plants are carefully and periodically indexed by biological, serological and molecular methods for tristeza, psorosis, exocortis, cachexia, citrus variegated chlorosis, citrus canker and huanglongbing. The Citrus Sanitation Center will maintain a supply of healthy propagation material and will continue a program initiated in 1966, consting in introducing, producing and releasing nucellar clones.La Estación Experimental Agroindustrial Obispo Colombres (EEAOC creó en el año 2004 el Centro de Saneamiento de Citrus (CSC para la ejecución de tareas de limpieza y diagnóstico de virus en cítricos. El objetivo de este centro es establecer y mantener un plantel de plantas madres cítricas, de variedades copa y portainjertos, de alta calidad genética y libre de plagas y enfermedades transmisibles por injerto. Este grupo de plantas se constituye como fuente primaria de material de propagación para productores, viveristas e investigadores del noroeste argentino. Las plantas madres de las principales variedades comerciales de cítricos se seleccionaron del banco de germoplasma de la EEAOC y se recuperaron por la técnica de microinjerto de ápices caulinares, procedimiento estándar utilizado en la limpieza de plantas cítricas. Periódicamente se verifica su sanidad por métodos biológicos, serológicos y moleculares para las

  12. Evaluation, grafting success and field establishment of cashew rootstock as influenced by VAM fungi.

    Science.gov (United States)

    Lakshmipathy, R; Balakrishna, A N; Bagyaraj, D J; Sumana, D A; Kumar, D P

    2004-11-01

    Seven isolates of vesicular arbuscular mycorrhizal (VAM) fungi were isolated from cashew rhizosphere soil of different cashew growing regions of South India. These seven isolates along with two more VAM fungi namely Acaulospora laevis and Glomus mosseae, which were found to be better symbionts for cashew during our earlier study were used to study their effectiveness on the growth and nutrition of cashew rootstock Ullal-1. Four promising VAM fungi were selected based on this study. Rootstocks inoculated with these four fungi were evaluated for their vigour through grafting success, using Ullal-3 cashew variety as scion. Grafting success was more in rootstocks inoculated with A. laevis and one of local isolates Glomus etunicatum. Grafts with rootstock treated with G. etunicatum and A. laevis survived and performed better when planted in the field compared to the uninoculated and other VAM fungal treatments.

  13. Untapped richness in Erik H. Erikson's rootstock.

    Science.gov (United States)

    Kivnick, Helen Q; Wells, Courtney K

    2014-02-01

    Erik H. Erikson published his groundbreaking theory of 8 stages of lifelong psychosocial development in 1950. His theory expanded psychoanalytic concepts of psychosexual development to include the importance of social dynamics; it transcended then-current thinking that psychological development culminated in early adulthood, acknowledging that systematic human development continues throughout the entire life cycle. The theory made Erikson a pioneer in developmental psychology. His last authored book, Vital Involvement in Old Age, rearticulated and elaborated 3 principles that, in different words, are rooted in his original theory of healthy life cycle development: (1) Dynamic Balance of Opposites; (2) Vital Involvement; and (3) Life in Time. Using a lens informed by knowledge gained over the past 30 years and by reflections of one of the original researchers on that project, the current manuscript seeks to spark new interest in Erikson's late-life contribution. It explains the principles in new detail, links them to relevant research, and suggests ways they could enable Erikson's ideas to further enrich gerontological practice and research.

  14. 76 FR 23449 - Citrus Canker, Citrus Greening, and Asian Citrus Psyllid; Interstate Movement of Regulated...

    Science.gov (United States)

    2011-04-27

    ..., clones, cultivars, strains, varieties, or hybrids of the genera Citrus and Fortunella, and all clones... in agricultural products and other commodities that pose a risk of harboring plant pest in ways...

  15. Determinação de metodologia para oisolamento de protoplastos de tangerina Cleópatra (Citrus reshni Hort. Methodology choice for protoplast isolation in Cleopatra mandarin (Citrus reshni Hort.

    Directory of Open Access Journals (Sweden)

    R.P. de Oliveira

    1995-04-01

    Full Text Available A hibridação somática via fusão de protoplastos vem sendo utilizada no melhoramento de porta-enxertos de citros em diversos países. Nos Estados Unidos, vários estudos demonstram a eficiência de procedimentos no isolamento e cultivo de protoplastos dessa frutífera. O presente trabalho foi realizado com o objetivo de avaliar o efeito do meio de cultivo de calos embriogênicos do porta-enxerto tangerina Cleópatra (Citrus reshni Hort. sobre o isolamento de protoplastos, bem como sugerir alterações de procedimento. Os resultados mostram a possibilidade do isolamento de 1.4 x 10(6 a 4.7 x 10(6 protoplastos por grama de calos da espécie estudada. Verificou-se que, o subcultivo dos calos de tangerina Cleópatra em meio de cultura, sem reguladores 1 hora, sob condições de escuro a 120 rpm, proporcionou maior eficiência de isolamento de protoplastos (4.7 x 10(6 protoplastos/g de calo.Somatic hybridization has been used for citrus rootstock breeding in many countries. In USA, many reports had proved the efficiency of procedures for the isolation and culture of citrus protoplasts. This research was conducted to evaluate the efficiency of procedures of protoplast isolation using embryogenic callus of the Cleópatra mandarin rootstock. Alterations were proposed to increase protoplast isolation and culture method. Results show the possibility of a protoplast yield of 1.4 to 4.7 x 10(6 pps/g.f.w. for Cleópatra tangerine rootstock callus. Protoplast yield can be raised to 4.7 x 10(6 pps/g.f.w. if the embryogenic callus are grown in a medium supplemented only with 4% sucrose and pre-treated with 1% w/v macerozyme for 1 hour, at 120 rpm, in dark, is applied before protoplast isolation.

  16. Monitoring Citrus Soil Moisture and Nutrients Using an IoT Based System

    Directory of Open Access Journals (Sweden)

    Xueyan Zhang

    2017-02-01

    Full Text Available Chongqing mountain citrus orchard is one of the main origins of Chinese citrus. Its planting terrain is complex and soil parent material is diverse. Currently, the citrus fertilization, irrigation and other management processes still have great blindness. They usually use the same pattern and the same formula rather than considering the orchard terrain features, soil differences, species characteristics and the state of tree growth. With the help of the ZigBee technology, artificial intelligence and decision support technology, this paper has developed the research on the application technology of agricultural Internet of Things for real-time monitoring of citrus soil moisture and nutrients as well as the research on the integration of fertilization and irrigation decision support system. Some achievements were obtained including single-point multi-layer citrus soil temperature and humidity detection wireless sensor nodes and citrus precision fertilization and irrigation management decision support system. They were applied in citrus base in the Three Gorges Reservoir Area. The results showed that the system could help the grower to scientifically fertilize or irrigate, improve the precision operation level of citrus production, reduce the labor cost and reduce the pollution caused by chemical fertilizer.

  17. Monitoring Citrus Soil Moisture and Nutrients Using an IoT Based System.

    Science.gov (United States)

    Zhang, Xueyan; Zhang, Jianwu; Li, Lin; Zhang, Yuzhu; Yang, Guocai

    2017-02-23

    Chongqing mountain citrus orchard is one of the main origins of Chinese citrus. Its planting terrain is complex and soil parent material is diverse. Currently, the citrus fertilization, irrigation and other management processes still have great blindness. They usually use the same pattern and the same formula rather than considering the orchard terrain features, soil differences, species characteristics and the state of tree growth. With the help of the ZigBee technology, artificial intelligence and decision support technology, this paper has developed the research on the application technology of agricultural Internet of Things for real-time monitoring of citrus soil moisture and nutrients as well as the research on the integration of fertilization and irrigation decision support system. Some achievements were obtained including single-point multi-layer citrus soil temperature and humidity detection wireless sensor nodes and citrus precision fertilization and irrigation management decision support system. They were applied in citrus base in the Three Gorges Reservoir Area. The results showed that the system could help the grower to scientifically fertilize or irrigate, improve the precision operation level of citrus production, reduce the labor cost and reduce the pollution caused by chemical fertilizer.

  18. Monitoring Citrus Soil Moisture and Nutrients Using an IoT Based System

    Science.gov (United States)

    Zhang, Xueyan; Zhang, Jianwu; Li, Lin; Zhang, Yuzhu; Yang, Guocai

    2017-01-01

    Chongqing mountain citrus orchard is one of the main origins of Chinese citrus. Its planting terrain is complex and soil parent material is diverse. Currently, the citrus fertilization, irrigation and other management processes still have great blindness. They usually use the same pattern and the same formula rather than considering the orchard terrain features, soil differences, species characteristics and the state of tree growth. With the help of the ZigBee technology, artificial intelligence and decision support technology, this paper has developed the research on the application technology of agricultural Internet of Things for real-time monitoring of citrus soil moisture and nutrients as well as the research on the integration of fertilization and irrigation decision support system. Some achievements were obtained including single-point multi-layer citrus soil temperature and humidity detection wireless sensor nodes and citrus precision fertilization and irrigation management decision support system. They were applied in citrus base in the Three Gorges Reservoir Area. The results showed that the system could help the grower to scientifically fertilize or irrigate, improve the precision operation level of citrus production, reduce the labor cost and reduce the pollution caused by chemical fertilizer. PMID:28241488

  19. Visible Light Image-Based Method for Sugar Content Classification of Citrus.

    Science.gov (United States)

    Wang, Xuefeng; Wu, Chunyan; Hirafuji, Masayuki

    2016-01-01

    Visible light imaging of citrus fruit from Mie Prefecture of Japan was performed to determine whether an algorithm could be developed to predict the sugar content. This nondestructive classification showed that the accurate segmentation of different images can be realized by a correlation analysis based on the threshold value of the coefficient of determination. There is an obvious correlation between the sugar content of citrus fruit and certain parameters of the color images. The selected image parameters were connected by addition algorithm. The sugar content of citrus fruit can be predicted by the dummy variable method. The results showed that the small but orange citrus fruits often have a high sugar content. The study shows that it is possible to predict the sugar content of citrus fruit and to perform a classification of the sugar content using light in the visible spectrum and without the need for an additional light source.

  20. Cytoplasmic inheritance of somatic hybrids and development of primers for cpSSR in Citrus%柑橘体细胞胞质遗传及叶绿体SSR引物开发

    Institute of Scientific and Technical Information of China (English)

    程运江

    2011-01-01

    以38个组合的柑橘体细胞杂种(或胞质杂种)为试验材料,综合应用RFLP、CAPS和cpSSR分子标记技术,对这些杂种的线粒体和叶绿体遗传组成进行了分析;同时对试验技术体系进行了完善与拓展,开发了柑橘叶绿体SSR标记;并对柑橘愈伤组织长期继代保存过程中胞质基因组遗传变异进行了分析,主要结果如下.%In the present study,cytoplasmic inheritance of Citrus somatic hybrids and cybrids from 38 interge-neric and interspecific fusion combinations was analyzed with restriction fragment length polymorphisms (RFLPs), cleaved amplified polymorphic sequence (CAPS) and chloroplast simple sequence repeat (cpSSR) markers. The experimental procedures were modified and optimized. A novel marker, cpSSR, was developed in Citrus and other tropical fruit crops. Meanwhile,genetic variations of organelle from 23 Citrus calli were analyzed. The main results were as follows:1. A simple and efficient method for genomic DNA extraction from woody fruit crops containing high level of polysaccharides was developed. This method involves a modified CTAB or SDS procedure employing a purification step to remove polysaccharides by using water saturated ether at the presence of 1. 25-1. 30 mol/L NaCl. The quality of DNA samples extracted with this method was suitable for PCR and RFLPs analysis and for long-term storage. In addition, this procedure was successfully applied in DNA isolation from the freezed or withered or senile leaves of Citrus and more than 20 kinds of tropical and subtropical fruit crops.2. Five universal pairs of chloroplast DNA (cpDNA) primer and 3 universal pairs of mitochondrial DNA (mtDNA) primers amplified monomorphic fragments among 4 intergeneric hybrids and 3 inter-spefic fusion combinations. After digested by restriction endonuclease, polymorphic mitochondrial CAPS markers were displayed in the 4 intergeneric combinations, while polymorphic chloroplast CAPS markers were found in 3

  1. Efeito da baixa temperatura noturna e do porta-enxerto na variação diurna das trocas gasosas e na atividade fotoquímica de laranjeira 'Val��ncia' Effects of low night temperature and rootstocks on diurnal variation of leaf gas exchange rates and photochemical activity of 'Valência' sweet orange plants

    Directory of Open Access Journals (Sweden)

    Daniela Favero São Pedro Machado

    2010-06-01

    limitações difusivas e metabólicas. Embora, Fv/Fm e Fq'/Fm' em laranjeira 'Valência' sobre 'Cravo' tenham sido mais afetados pelo resfriamento em comparação às laranjeiras sobre 'Swingle', esses não contribuíram para a redução da assimilação de CO² (A. Porém, o frio noturno causou aumento da atividade dos drenos alternativos de elétrons (aumento da relação entre o transporte aparente de elétrons e a assimilação de CO², reduzindo a eficiência aparente de carboxilação de forma mais significante em 'Valência' sobre 'Cravo' do que sobre 'Swingle'. Estes resultados confirmam a hipótese de que a ocorrência de frio noturno afeta a fotossíntese de laranjeira 'Valência' sendo os efeitos do resfriamento dependentes do porta-enxerto.Decreases in photosynthesis during winter season are probably caused by low night temperature, even under non-limiting environmental conditions during the diurnal period. Citrus orchards are formed by grafted plants, being the 'Swingle' citrumelo rootstock recommended in areas with occurrence of low temperatures. However, the physiological mechanisms related to larger growth and crop yield in those plants are poorly understood. The aim of this study was to test the hypothesis that the effect of low night temperature in photosynthesis of sweet orange plants is dependent on the rootstock species, with 'Swingle' citrumelo (Citrus paradise x Poncirus trifoliata inducing higher tolerance to overnight chilling when compared to 'Rangpur' lime (Citrus limonia rootstock. Six-month old 'Valência' (Citrus sinensis sweet orange plants grown in plastic bags (5 L were exposed overnight (12 h to temperatures of 20 and 8 ºC. The thermal treatment was carried out inside a growth chamber where only the upper plant shoots were exposed to temperature variation. Measurements of diurnal courses of leaf gas exchange and photochemical activity were taken under natural environmental conditions. Chilling night caused larger reduction on CO2

  2. Identification of photoperception and light signal transduction pathways in citrus

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    Vera Quecini

    2007-01-01

    Full Text Available Studies employing model species have elucidated several aspects of photoperception and light signal transduction that control plant development. However, the information available for economically important crops is scarce. Citrus genome databases of expressed sequence tags (EST were investigated in order to identify genes coding for functionally characterized proteins responsible for light-regulated developmental control in model plants. Approximately 176,200 EST sequences from 53 libraries were queried and all bona fide and putative photoreceptor gene families were found in citrus species. We have identified 53 orthologs for several families of transcriptional regulators and cytoplasmic proteins mediating photoreceptor-induced responses although some important Arabidopsis phytochrome- and cryptochrome-signaling components are absent from citrus sequence databases. The main gene families responsible for phototropin-mediated signal transduction were present in citrus transcriptome, including general regulatory factors (14-3-3 proteins, scaffolding elements and auxin-responsive transcription factors and transporters. A working model of light perception, signal transduction and response-eliciting in citrus is proposed based on the identified key components. These results demonstrate the power of comparative genomics between model systems and economically important crop species to elucidate several aspects of plant physiology and metabolism.

  3. Molecular and physiological changes in response to salt stress in Citrus macrophylla W plants overexpressing Arabidopsis CBF3/DREB1A.

    Science.gov (United States)

    Alvarez-Gerding, Ximena; Espinoza, Carmen; Inostroza-Blancheteau, Claudio; Arce-Johnson, Patricio

    2015-07-01

    Plant stress induced by high salinity has leading to an important reduction in crop yields. Due to their tropical origin, citrus fruits are highly sensitive to salts. Rootstocks are the root system of fruit trees, regulating ion uptake and transport to the canopy. Therefore, increasing their salt tolerance could improve the salt tolerance of the fruit tree. For this, we genetically-transformed an important rootstock for lemon, Citrus macrophylla W, to constitutively express the CBF3/DREB1A gene from Arabidopsis, a well-studied salinity tolerance transcription factor. Transgenic lines showed normal size, with no dwarfism. Under salt stress, some transgenic lines showed greater growth, similar accumulation of chloride and sodium in the leaves and better stomatal conductance, in comparison to wild-type plants. Quantitative real-time analyses showed a similar expression of several CBF3/DREB1A target genes, such as COR15A, LEA 4/5, INV, SIP1, P5CS, GOLS, ADC2 and LKR/SDH, in transgenic lines and wild type plants, with the exception of INV that shows increased expression in line 4C15. Under salt stress, all measured transcript increased in both wild type and transgenics lines, with the exception of INV. Altogether, these results suggest a higher salt tolerance of transgenic C. macrophylla plants induced by the overexpression of AtCBF3/DREB1A.

  4. [Evaluation of zinc deficiency tolerance in different kinds of apple rootstocks].

    Science.gov (United States)

    Fan, Xiao-dan; Liu, Fei; Wang, Yan-an; Fu, Chun-xia; Yan, Yu-jing; Sha, Guang-li; Shu, Huai-rui

    2015-10-01

    The objective of this study was to screen and evaluate the zinc deficiency tolerance among eight apple rootstocks, i.e., Malus baccata, M. rockii, M. xiaojinensis, M. sikkimensis, M. sieversii, M. robusta, M. hupehensis and Malus 'Flame'. The experiment took these 8 kinds of root-stocks as the research materials to observe and analyze the index of the rootstock's height, dry biomass, root architecture and zinc concentration, and with help of the fuzzy membership function to work out a comprehensive evaluation on their zinc deficiency tolerance. The result showed that several obvious zinc deficiency symptoms were observed in three kinds of rootstocks (M. rockii, M. sikkimensis and M. sieversii), such as dwarfed plant and newborn small leaves, while such symptoms were not obvious in M. xiaojinensis and M. 'Flame'. The plant biomass, height and zinc accumulation of aerial part greatly decreased under zinc deficiency stress, while smaller reduction was observed in M. xiaojinensis than in other rootstocks. M. xiaojinensis and M. baccata had higher zinc concentrations in leaves than others. According to the fuzzy membership function and cluster analysis, the resistance of the eight apple rootstocks to zinc deficiency was ranked: M. xiaojinensis was the highest one; M. 'Flame' was the second; M. baccata, M. sikkimensis, M. robusta and M. hupehensis were rather weaker; M. rockii and M. sieversii demonstrated the highest sensitivity to zinc deficiency.

  5. Anatomical and histological researches on rootstock and scion compatibility in early period after grafting in avocado

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    Süleyman BAYRAM

    2014-12-01

    Full Text Available Avocado seedling rootstocks are used entirely due to easier and cheaper production in conditions of our country. However, a study on compatibility of scion and rootstock of varieties used as seedling rootstock, have not been produced in our country yet. Thus, seedlings of the 'Bacon', 'Fuerte', 'Hass' and 'Zutano' varieties produced as commercial varieties along with 'Topa Topa' and 'Mexicola' varieties used as a source of seedling rootstocks were studied under greenhouse conditions between the years 2009-2011. Determination of the scion and rootstock compatibility was purposed in the graft sections during certain periods after grafting of 'Hass' variety with these seedlings. As a result; graft union formations in samples of all combinations successfully realized in the anatomical and histological studies after 30 and 90 days from grafting and a negative finding regarding to incompatibility were not met. However, more studies should be made for determination of incompatibility that may arise in between rootstocks and scions in the later years.

  6. YIELD AND QUALITY OF ‘PERA’ SWEET ORANGE GRAFTED ON DIFFERENT ROOTSTOCKS UNDER RAINFED CONDITIONS

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    ANTONIO HÉLDER RODRIGUES SAMPAIO

    Full Text Available ABSTRACT This study aimed to evaluate, under field conditions, different combinations between ‘Pera’ sweet orange and eight rootstocks: ‘Rangpur’ lime (RL, ‘Volkamer’ lemon (VL, ‘Cleopatra’ mandarin (CM, ‘Sunki Maravilha’ mandarin (SMM, ‘Indio’ and ‘Riverside’ citrandarins, and VL x RL (‘Rangpur’ lime-010 and TH-051 hybrids. The soil water matric potential (?m was characterized for all scion-rootstock combinations at distance of 1.0m from the trunk at the plant row direction and depths of 0.25 m, 0.50 m 0.90 m in the dry and wet seasons. For two years, fruit production parameters and fruit quality were assessed. Differences of Ym among scion-rootstock combinations were observed during the dry season (p=0.05. The lowest Ym values for RL and the highest for TH-051 indicate the existence of different intrinsic mechanisms affecting the water extraction of each scion-rootstock combination. Rootstocks have influenced fruit yield and quality (p=0.05. The best combinations for fruit quality and production were sweet orange grafted on ‘Riverside’, ‘Indio’ and TH-051 rootstocks.

  7. Survey for Citrus diseases in French Guiana

    OpenAIRE

    Thermoz, Jean-Pierre

    2007-01-01

    The presence on the continent of major threats for Citrus orchards has required a survey to assess the situation of Citrus pathogens in the French territory of Guiana. Agriculture in French Guiana is located on the coast (about 300 Kms from west to east and 50 Km wide). There are 1200 Ha of Citrus orchards (Ministry of Agriculture). Citrus are grown either for export (Tahiti lime) or for local consumption : sweet oranges, tangerines and hybrids. Trees are grafted on Carrizo citrange, Rough le...

  8. Soil Micronutrients and Citrus Growth

    Institute of Scientific and Technical Information of China (English)

    OUYANGTAO

    1993-01-01

    By using nutritional diagnosis of citrus leaves and determining soil micronutrients,the relationship between soil micronutrients and citrus growth in southern China has been studied.Studies showed that there was a significant positive correlation between available micronutrients (such as Zn,Mo,Cu)in the soil and the corresponding nutrients in citrus leaves.Thus,one can roughly learn of the sufficiency or deficiency of certain nutrients in soils by analyzing citrus leaves.Rational spray of Zn B or Mo fertilizer not only improved citrus yields but also increased the total sugar of Satsuma mandarin and of Xinhui orange by 2.9 and 17.2% respectively compared with the control.Spraying Mo fertilizer increased the vitamin C content of Satsuma mandarin juice by 4.7%-8.4%,maturated fruits 7-10 days earlier and gave the peel a brighter color.The ultramicroscopic characteristics of Zn-deficient citrus leaves were investigated under an electron microscope.Results showed that the Zn-deficient leaf cell was characterized mainly by poor cytoplasm,endoplasmic reticula and ribosomes and by big starch grains in the chloroplast.As a result of spraying Zn fertilizer the structure of the cell returned to normal,the cytoplasm became rich and the amount of chloroplast increased.There also appeared a great deal of multiform endoplasmic reticula,thus promoting the photosynthesis of Zn-deficient plants.This provides a cytologico-theoretical basis for fertilization of high-yielding citrus trees.

  9. The IDA peptide controls abscission in Arabidopsis and Citrus

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    Leandro H Estornell

    2015-11-01

    Full Text Available Organ abscission is an important process in plant development and reproduction. During abscission, changes in cellular adhesion of specialised abscission zone (AZ cells ensure the detachment of infected organs or those no longer serving a function to the plant. In addition, abscission also plays an important role in the release of ripe fruits. Different plant species display distinct patterns and timing of organ shedding, most likely adapted during evolution to their diverse life styles. However, it appears that key regulators of cell separation may have conserved function in different plant species. Here we investigate the functional conservation of the citrus orthologue of the Arabidopsis peptide ligand INFLORESCENCE DEFICIENT IN ABSCISSION (AtIDA, controlling floral organ abscission. We discuss the possible implications of modifying the citrus IDA orthologue for citrus fruit production.

  10. Analysis of SSR in Citrus Sequences from EMBL Database

    Institute of Scientific and Technical Information of China (English)

    MENG Hai-jun; CAO Qing-qin; HU Zhi-yong; LIU Gao-ping; CHENG Yun-jiang; DENG Xiu-xin

    2005-01-01

    Abundance of simple sequence repeat (SSR) in Citrus sequences from EMBL database was investigated by using computer program MISA (MIcroSAtellite), which aimed to provide useful information for the development of SSR markers.Among 32 896 sequences of Citrus, 4987 SSRs were found in 4167 sequences and the average distance between SSRs was approximately 3.5 kb. Mononucleotide repeats (50.6%) were the most abundant repeats. And di-, tri-, tetra-, penta- and hexa-nucleotide repeats were 22.8, 25.2, 1, 0.08, and 0.36%, respectively. The most abundant motif was A/T followed in descending order by AG/CT, AC/GT, AT/TA. AAT/ATT, AAG/CTT, AGC/CGT, ACG/CTG and C/G. They comprised about90% of all microsatellites. Ten primer pairs were designed, and three of them produced clear visible bands among Citrus and its related genera.

  11. The push-pull strategy for citrus psyllid control.

    Science.gov (United States)

    Yan, Huaxue; Zeng, Jiwu; Zhong, Guangyan

    2015-07-01

    The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the only natural vector of Candidatus Liberibacter asiaticus that causes citrus huanglongbing (HLB), a most destructive disease of citrus. Currently, no remedial therapy exists for the disease, and so effective control of ACP is very important in curbing the transmission of the disease. The push-pull strategy should be thoroughly explored as an approach to ACP management. This mini-review summarises the current progress towards more effective repellent and attractant chemicals through investigating known repellent and attractive plants. Interactions between ACP and its host plants are also addressed, with emphasis on the possible involvement of the host biochemicals in attracting the insect. Potential ways to increase the effectiveness of the pull-push strategy are briefly discussed. It is expected that the pull-push strategy will be gradually developed following more extensive research.

  12. New excised-leaf assay method to test inoculativity of Asian citrus psyllid (Hemiptera: Psyllidae) with Candidatus Liberibacter asiaticus associated with citrus huanglongbing disease.

    Science.gov (United States)

    Ammar, El-Desouky; Walter, Abigail J; Hall, David G

    2013-02-01

    The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the primary vector of Candidatus Liberibacter asiaticus (Las) associated with huanglongbing, or citrus greening, the most devastating citrus (Citrus spp.) disease worldwide. Here, we developed a new "excised-leaf assay" that can speed up Las-inoculativity tests on Asian citrus psyllid from the current 3-12 mo (when using whole citrus seedlings for inoculation) to only 2-3 wk. Young adults of Asian citrus psyllid that had been reared on Las-infected plants were caged on excised healthy sweet orange [Citrus sinensis (L.) Osbeck] leaves for a 1-2-wk inoculation access periods (IAP), and then both psyllids and leaves were tested later by quantitative polymerase chain reaction (PCR). When single adults were tested per leaf, percentages of Las-positive leaves averaged 2-6% by using HLBaspr primers and 10-20% by using the more sensitive LJ900 primers. Higher proportions of Las-positive leaves were obtained with 1) higher densities of inoculating psyllids (5-10 adults per leaf), 2) longer IAPs, and 3) incubation of leaves for 1 wk postinoculation before PCR. Logistic regression analysis indicated a positive correlation between Las titer in Asian citrus psyllid adults tested singly and the probability of detecting Las in the inoculated leaves, correlations that can be very useful in epidemiological studies. Comparison between excised leaves and whole seedlings, inoculated consecutively for 1 wk each by one or a group of psyllids, indicated no significant difference between Las detection in excised leaves or whole plants. This new excised-leaf assay method saves considerable time, materials, and greenhouse space, and it may enhance vector relation and epidemiological studies on Las and potentially other Liberibacter spp. associated with huanglongbing disease.

  13. Genome wide characterization of short tandem repeat markers in sweet orange (Citrus sinensis.

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    Manosh Kumar Biswas

    Full Text Available Sweet orange (Citrus sinensis is one of the major cultivated and most-consumed citrus species. With the goal of enhancing the genomic resources in citrus, we surveyed, developed and characterized microsatellite markers in the ≈347 Mb sequence assembly of the sweet orange genome. A total of 50,846 SSRs were identified with a frequency of 146.4 SSRs/Mbp. Dinucleotide repeats are the most frequent repeat class and the highest density of SSRs was found in chromosome 4. SSRs are non-randomly distributed in the genome and most of the SSRs (62.02% are located in the intergenic regions. We found that AT-rich SSRs are more frequent than GC-rich SSRs. A total number of 21,248 SSR primers were successfully developed, which represents 89 SSR markers per Mb of the genome. A subset of 950 developed SSR primer pairs were synthesized and tested by wet lab experiments on a set of 16 citrus accessions. In total we identified 534 (56.21% polymorphic SSR markers that will be useful in citrus improvement. The number of amplified alleles ranges from 2 to 12 with an average of 4 alleles per marker and an average PIC value of 0.75. The newly developed sweet orange primer sequences, their in silico PCR products, exact position in the genome assembly and putative function are made publicly available. We present the largest number of SSR markers ever developed for a citrus species. Almost two thirds of the markers are transferable to 16 citrus relatives and may be used for constructing a high density linkage map. In addition, they are valuable for marker-assisted selection studies, population structure analyses and comparative genomic studies of C. sinensis with other citrus related species. Altogether, these markers provide a significant contribution to the citrus research community.

  14. Genome wide characterization of short tandem repeat markers in sweet orange (Citrus sinensis).

    Science.gov (United States)

    Biswas, Manosh Kumar; Xu, Qiang; Mayer, Christoph; Deng, Xiuxin

    2014-01-01

    Sweet orange (Citrus sinensis) is one of the major cultivated and most-consumed citrus species. With the goal of enhancing the genomic resources in citrus, we surveyed, developed and characterized microsatellite markers in the ≈347 Mb sequence assembly of the sweet orange genome. A total of 50,846 SSRs were identified with a frequency of 146.4 SSRs/Mbp. Dinucleotide repeats are the most frequent repeat class and the highest density of SSRs was found in chromosome 4. SSRs are non-randomly distributed in the genome and most of the SSRs (62.02%) are located in the intergenic regions. We found that AT-rich SSRs are more frequent than GC-rich SSRs. A total number of 21,248 SSR primers were successfully developed, which represents 89 SSR markers per Mb of the genome. A subset of 950 developed SSR primer pairs were synthesized and tested by wet lab experiments on a set of 16 citrus accessions. In total we identified 534 (56.21%) polymorphic SSR markers that will be useful in citrus improvement. The number of amplified alleles ranges from 2 to 12 with an average of 4 alleles per marker and an average PIC value of 0.75. The newly developed sweet orange primer sequences, their in silico PCR products, exact position in the genome assembly and putative function are made publicly available. We present the largest number of SSR markers ever developed for a citrus species. Almost two thirds of the markers are transferable to 16 citrus relatives and may be used for constructing a high density linkage map. In addition, they are valuable for marker-assisted selection studies, population structure analyses and comparative genomic studies of C. sinensis with other citrus related species. Altogether, these markers provide a significant contribution to the citrus research community.

  15. Colheita de citros e obtenção de dados para mapeamento da produtividade Characterization of harvest systems and development yield mapping for citrus

    Directory of Open Access Journals (Sweden)

    José P. Molin

    2007-04-01

    Full Text Available A citricultura é de fundamental importância para a economia brasileira devido a sua expressiva participação na exportação e pela geração de empregos. A colheita manual é atualmente realizada na totalidade das propriedades citrícolas nacionais. A ausência de técnicas para a geração de mapas de produtividade em citros é uma das grandes dificuldades para a implantação da agricultura de precisão, o que justifica empreender técnicas e equipamentos para essa finalidade. Neste trabalho, teve-se o objetivo de ter o correto entendimento dos sistemas de colheita existentes, suas características úteis e limitações. A partir de então, desenvolveu-se e testou-se uma proposta de geração de dados para obtenção de mapas de produtividade sem interferir no processo vigente. Procedeu-se à pesagem de uma população de sacolões ("big bag" para aferir a informação de massa estimada pelo responsável pela colheita. Na seqüência, realizou-se o georreferenciamento de todos os sacolões de uma área. A partir da largura da faixa de colheita e do cálculo de distância entre os sacolões, obtiveram-se as áreas de contribuição de cada um, e com a massa estimada determinou-se a produtividade dos pontos. Esses dados foram interpolados gerando o mapa de produtividade. A estimativa de massa dos sacolões mostrou-se aceitável e o método válido para a coleta de dados e a geração do mapa de produtividade.Citriculture activity is important for the Brazilian economy due to its expressive participation on exporting and for the generation of a number of job positions. Manual harvesting is currently predominant. Routine generation of yield mapping for citrus is necessary for implementing precision agriculture practices, what justifies efforts for developing techniques for data collection. The objective of this research was to promote the correct understanding of the variations on harvesting systems, their useful characteristics and

  16. Development of SSR Markers from Citrus BAC End Sequences and Their Integration into Linkage Map%柑桔BES-SSR标记开发及连锁图延伸和加密

    Institute of Scientific and Technical Information of China (English)

    马喜军; 龚桂芝; 彭祝春; 韩学智; 洪棋斌

    2012-01-01

    Simple Sequence Repeats (SSR) were surveyed in citrus BAC-End sequence (BES) for the development of new SSR markers to extend and saturate existing genetic map. 22 403 SSRs with 1~6 bp motif were identified in 46 339 citrus BESs retrieved from NCBI. The estimated frequency of SSRs was approximately 1/1. 25 kb, nearly twice the frequency found in Citrus Expressed Sequence Tags. 323 primers were selected in the present mapping study,of which 40 were mono-nucleotide repeats, 184 di-nucleotide repeats, 99 tri-nucleotide or above repeats. Polymorphism tests showed that 316 primer-pairs (98%) could be amplified successfully and 173 pairs (55%) were polymorphic. Among the polymorphic primers, 15 pairs were of mono-nucleotide repeats, 100 pairs of di-nucleotide repeats,58 pairs of tri-nucleotide or above repeats. A new linkage map was produced by combining the segregating data of new markers and markers in the previous map. When compared with the published map, the new map integrated 334 SSR markers, 9 linkage groups and covered 844. 2 cM of citrus genome with an average genetic distance standing at 2. 53 cM. The results demonstrated that citrus BES was good for SSR marker development and the developed markers were useful in extending and saturating the citrus genetic maps. So this will provide a reference for development of other species SSR markers and lay a good foundation for citrus gene mapping,map-based cloning and marker-assisted breeding.%为了系统性地开发和拓展柑桔SSR标记,通过对公布的柑桔BAC文库末端序列(BAC-End sequence,BES)进行SSR分析,选择1500个SSR位点设计合成并检测323对引物.结果表明:(1)从总长度为28.1 Mb的46 339条序列中共检测出22403个SSR位点,约每2条序列就会出现一个SSR位点,发生频率为48%,相当于平均1.25 kb的序列中就会出现1个SSR,频率约为柑桔EST的2倍,且不同核心重复序列的SSR发生特点与EST也不同.(2)所合成的323对引物中,有效扩增316

  17. CRECIMIENTO Y DESARROLLO DE LA LIMA ÁCIDA (Citrus latifolia Tanaka, cv. Tahití, EN SUELOS CON LIMITACIONES POR PROFUNDIDAD EFECTIVA, EN UN BOSQUE SECO TROPICAL GROWTH AND DEVELOPMENT OF LIME (Citrus latifolia Tanaka, cv. Tahiti, IN SOILS WITH LIMITATIONS BY EFFECTIVE DEPTH IN A TROPICAL DRY FOREST

    Directory of Open Access Journals (Sweden)

    Gabriel Fernando Ochoa Agudelo

    2012-06-01

    Full Text Available Resumen. Se evaluó la evolución de la biomasa, la distribución diferencial de ésta entre los órganos y algunos parámetros del crecimiento y desarrollo, de la lima ácida (Citrus latifolia Tanaka, cv. Tahití, injertada sobre Carrizo y Kryder. El cultivo se estableció en suelos con limitaciones por profundidad efectiva (PE entre 10 y 20 cm; las evaluaciones se realizaron a los 24, 32 y 39 meses después del trasplante. Se debe tener presente que el crecimiento de las raíces está condicionado a los atributos edáficos en donde se establecen los cultivos, en especial los perennes, en cuyo caso existen requerimientos mínimos de PE para el adecuado desarrollo de los árboles; se establecieron diferencias entre la biomasa acumulada, como consecuencia de ésta limitación. Al comparar el crecimiento de las plantas con la PE se evidenció que los individuos que crecieron en suelos con PE de 20 cm, presentaron un desarrollo relativamente semejante a plantaciones sin limitaciones de este tipo; mientras que, en suelos con PE inferior a 10 cm, la respuesta fue 3 a 5 veces menor.Abstract. It was evaluated the evolution of biomass, its differential distribution among the organs and some parameters of growth and development of acid lime (Citrus latifolia Tanaka, cv. Tahiti, grafted on Carrizo and Kryder patterns. The plants were established in soils with limitations by its effective depth (ED, which ranged between 10 and 20 cm. Assessments were effectuated at 24, 32 and 39 months after transplantation. It is must to keep in mind that root growth is conditioned to the soil attributes of the site where the crops are established, especially in the case of perennials, which have requirements of minimum PE in order to achieve an adequate development. Differences were established between biomass accumulated as a result of the limitation in effective depth. When comparing the growth of plants with ED, we found that the individuals that grew up in soils with

  18. A dark incubation period is important for Agrobacterium-mediated transformation of mature internode explants of sweet orange, grapefruit, citron, and a citrange rootstock.

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    Mizuri Marutani-Hert

    Full Text Available BACKGROUND: Citrus has an extended juvenile phase and trees can take 2-20 years to transition to the adult reproductive phase and produce fruit. For citrus variety development this substantially prolongs the time before adult traits, such as fruit yield and quality, can be evaluated. Methods to transform tissue from mature citrus trees would shorten the evaluation period via the direct production of adult phase transgenic citrus trees. METHODOLOGY/PRINCIPAL FINDINGS: Factors important for promoting shoot regeneration from internode explants from adult phase citrus trees were identified and included a dark incubation period and the use of the cytokinin zeatin riboside. Transgenic trees were produced from four citrus types including sweet orange, citron, grapefruit, and a trifoliate hybrid using the identified factors and factor settings. SIGNIFICANCE: The critical importance of a dark incubation period for shoot regeneration was established. These results confirm previous reports on the feasibility of transforming mature tissue from sweet orange and are the first to document the transformation of mature tissue from grapefruit, citron, and a trifoliate hybrid.

  19. Comportamento agronômico inicial da cv. Chimarrita enxertada em cinco porta-enxertos de pessegueiro Agronomical behavior of cv. Chimarrita on five rootstocks of peach trees

    Directory of Open Access Journals (Sweden)

    Moacir da Silva Rocha

    2007-01-01

    Full Text Available O trabalho teve por objetivo avaliar a resposta agronômica da cv. Chimarrita enxertada em cinco porta-enxertos, nas condições edafoclimáticas da região de Pelotas-RS, no período de 2003 a 2005. Durante o período de execução do experimento, foram avaliados o diâmetro do tronco do porta-enxerto e da cultivar-copa, comprimento médio dos ramos principais, volume de copa, massa fresca e massa seca do material vegetal retirado nas podas verde e de inverno, índice de intensidade de poda, massa média dos frutos, produção por planta, eficiência produtiva, produção por hectare, sólidos solúveis totais, firmeza da polpa, diâmetro e coloração dos frutos. O porta-enxerto 'Capdeboscq' induziu o maior crescimento vegetativo na cv. Chimarrita durante os três anos de avaliação, seguido do porta-enxerto 'Okinawa'. Este, por sua vez, induziu o maior rendimento produtivo (1,65 t ha-1. A cv. Capdeboscq proporcionou a obtenção de frutos com maior massa. Os porta-enxertos 'GF 305' e 'Aldrighi' induziram menor desenvolvimento vegetativo e a mais baixa produtividade (0,52 t.ha-1 .The objective for this study was to evaluate the agronomical behavior of cv. Chimarrita on five rootstocks of peach trees in Pelotas- RS from 2003 to 2005. The variables evaluated were: trunk diameters of the rootstock and of the scion; length of the annual terminal growth; volume of the canopy; fresh and dry weight of the material taken by the summer and winter pruning; pruning intensity index; fruit weight; fruit production per tree; production efficiency; productivity per hectare; total soluble solids; pulp firmness; and fruit diameter and color. It was observed that the trees from: rootstock 'Capdeboscq' promoted higher vegetative growth and larger fruits, followed by the ones from the rootstock 'Okinawa' which promoted the highest yield (1, 65 t.ha-1; the rootstock 'GF 305' and 'Aldrighi' had the lowest vegetative development and yield (0, 52 t.ha-1.

  20. Improvement of grafted watermelon transplant survival as a result of size and starch increases over time caused by rootstock fatty alcohol treatment Part II

    Science.gov (United States)

    Fatty alcohol treatments can be used to eliminate the meristem of cucurbit (Family Cucurbitaceae) rootstocks which prevents regrowth when grafting, but the effects of the treatment on the rootstock have not been documented. Two rootstock types, ‘Emphasis’ bottle gourd (Lagenaria siceraria) and ‘Car...

  1. Isolation, classification and transcription profiles of the AP2/ERF transcription factor superfamily in citrus.

    Science.gov (United States)

    Xie, Xiu-lan; Shen, Shu-ling; Yin, Xue-ren; Xu, Qian; Sun, Chong-de; Grierson, Donald; Ferguson, Ian; Chen, Kun-song

    2014-07-01

    The AP2/ERF gene family encodes plant-specific transcription factors. In model plants, AP2/ERF genes have been shown to be expressed in response to developmental and environmental stimuli, and many function downstream of the ethylene, biotic, and abiotic stress signaling pathways. In citrus, ethylene is effective in regulation citrus fruit quality, such as degreening and aroma. However, information about the citrus AP2/ERF family is limited, and would enhance our understanding of fruit responses to environmental stress, fruit development and quality. CitAP2/ERF genes were isolated using the citrus genome database, and their expression patterns analyzed by real-time PCR using various orange organs and samples from a fruit developmental series. 126 sequences with homologies to AP2/ERF proteins were identified from the citrus genome, and, on the basis of their structure and sequence, assigned to the ERF family (102), AP2 family (18), RAV family (4) and Soloist (2). MEME motif analysis predicted the defining AP2/ERF domain and EAR repressor domains. Analysis of transcript accumulation in Citrus sinensis cv. 'Newhall' indicated that CitAP2/ERF genes show organ-specific and temporal expression, and provided a framework for understanding the transcriptional regulatory roles of AP2/ERF gene family members in citrus. Hierarchical cluster analysis and t tests identified regulators that potentially function during orange fruit growth and development.

  2. Desenvolvimento vegetativo, produção e qualidade dos frutos da laranjeira ‘Folha Murcha' sobre seis porta-enxertos no Norte do Paraná Vegetative growth, yield and quality fruits of the ‘Folha Murcha' orange on six rootstocks in North Parana, Brazil

    Directory of Open Access Journals (Sweden)

    Neusa Maria Colauto Stenzel

    2005-12-01

    variedades copa de laranja.This research evaluated, in Londrina, PR, Brazil, ‘Folha Murcha' orange trees on the rootstocks: ‘Caipira' orange (Citrus sinensis (L. Osb., ‘Rangpur' lime (Citrus limonia Osb., ‘Sunki' mandarin (Citrus sunki Hort. ex Tan., ‘Florida' rough lemon (Citrus jambhiri Lush., ‘Cleopatra' mandarin (Citrus reshni Hort. ex Tan., and ‘Volkamer' lemon (Citrus volkameriana Ten. & Pasq.. The experimental design was used as randomized blocks with six rootstocks as treatments, five replications and three plants per plot. Height, diameter, and canopy volume were significantly higher in trees budded on ‘Caipira' orange, when compared with those budded on ‘Volkamer' lemon. The smallest difference between trunk diameters below/above the bud occurred in trees on ‘Rangpur' lime and ‘Sunki' mandarin. Cumulative yield was superior for trees on ‘Rangpur' lime and ‘Caipira' orange, without showing statistical difference between themselves, but were significantly different from those on ‘Cleopatra' mandarin and ‘Volkamer' lemon. Yield efficiency was not influenced by the studied rootstocks. Fruit weight was significantly higher for trees on ‘Sunki' mandarin, compared to those on ‘Rangpur' lime, ‘Florida' rough lemon, and ‘Volkamer' lemon. Total soluble solids (TSS showed high contents in fruits of ‘Folha Murcha' orange on ‘Volkamer' lemon and on ‘Rangpur' lime, without differences between themselves. Total titratable acidity (TTA, (TSS/TTA ratio, and juice color were not influenced by the rootstocks tested. ‘Rangpur' lime and ‘Volkamer' lemon provided significantly higher technological index values in relation to the other rootstocks. The juice quality parameters evaluated were within the acceptable standards for orange canopy varieties.

  3. Effectivity of Kaffir lime (Citrus hystrix, Nasnaran Mandarin (Citrus amblycarpa, and Pomelo (Citrus maxima Leaf Extract Against Aedes aegypti Larvae

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    Hebert Adrianto

    2014-03-01

    Full Text Available The used of chemicals as larvicidal may causing resistance, health problem, and environment problem. Leaf extracts of Citrus as biolarvicidal against Aedes aegypti larvae can be used as an alternative larvicidal. The aims of this study is to find out the species of Citrus in the study sample, which is the most effective as biolarvicidal. This study was conducted using nested experiment design, with six treatments and five replicates. Larvae mortality was observed after 24 and 48 hours. Then, data were analyzed by probit. The results of this study show that (1 the LC95 value after 24 hours of exposure of leaf extracts of Citrus hystrix, Citrus amblycarpa, and Citrus maxima, were each 3,176 ppm; 4,174 ppm; and 6,369 ppm. (2 the LC95 value after 48 hours of exposure of leaf extracts of Citrus hystrix, Citrus amblycarpa, and Citrus maxima, were each 2,499 ppm; 3,256 ppm; and 4,886 ppm. (3 leaf extract of Citrus hystrix is the most effective among others as biolarvicidal against Aedes aegypti larvae. Leaf extract of Citrus hystrix can be used as alternative biolarvicidal.

  4. Genome Wide Characterization of Short Tandem Repeat Markers in Sweet Orange (Citrus sinensis)

    OpenAIRE

    Biswas, Manosh Kumar; Xu, Qiang; Mayer, Christoph; Deng, Xiuxin

    2014-01-01

    Sweet orange (Citrus sinensis) is one of the major cultivated and most-consumed citrus species. With the goal of enhancing the genomic resources in citrus, we surveyed, developed and characterized microsatellite markers in the ≈347 Mb sequence assembly of the sweet orange genome. A total of 50,846 SSRs were identified with a frequency of 146.4 SSRs/Mbp. Dinucleotide repeats are the most frequent repeat class and the highest density of SSRs was found in chromosome 4. SSRs are non-randomly dist...

  5. Apple replant disease and the –omics: interaction of apple rootstock metabolome and the soil microbiome

    Science.gov (United States)

    Apple replant disease (ARD) negatively impacts tree health and reduces crop yield in new orchard plantings. Use of tolerant rootstock cultivars can diminish the growth limiting effects of ARD; however specific rootstock attributes enabling ARD tolerance are not understood. Systems biology tools were...

  6. Citrus plastid-related gene profiling based on expressed sequence tag analyses

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    Tercilio Calsa Jr.

    2007-01-01

    Full Text Available Plastid-related sequences, derived from putative nuclear or plastome genes, were searched in a large collection of expressed sequence tags (ESTs and genomic sequences from the Citrus Biotechnology initiative in Brazil. The identified putative Citrus chloroplast gene sequences were compared to those from Arabidopsis, Eucalyptus and Pinus. Differential expression profiling for plastid-directed nuclear-encoded proteins and photosynthesis-related gene expression variation between Citrus sinensis and Citrus reticulata, when inoculated or not with Xylella fastidiosa, were also analyzed. Presumed Citrus plastome regions were more similar to Eucalyptus. Some putative genes appeared to be preferentially expressed in vegetative tissues (leaves and bark or in reproductive organs (flowers and fruits. Genes preferentially expressed in fruit and flower may be associated with hypothetical physiological functions. Expression pattern clustering analysis suggested that photosynthesis- and carbon fixation-related genes appeared to be up- or down-regulated in a resistant or susceptible Citrus species after Xylella inoculation in comparison to non-infected controls, generating novel information which may be helpful to develop novel genetic manipulation strategies to control Citrus variegated chlorosis (CVC.

  7. Teste de porta-enxertos intergenéricos para marmeleiros em condições de viveiro Tests of intergeneric rootstocks for quinces in nursery conditions

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    Rafael Pio

    2009-04-01

    Full Text Available Os marmeleiros sempre foram propagados comercialmente mediante o enraizamento de estacas. Devido ao baixo vigor das mudas, principalmente nos primeiros anos após o plantio, alguns trabalhos foram desenvolvidos no Brasil a fim de viabilizar a utilização do marmeleiro 'Japonês' (Chaenomeles sinensis Koehne como porta-enxerto para marmelos. Os resultados foram satisfatórios, mas frente à falta de outras opções de porta-enxertos mais vigorosos para marmeleiros e devido a observações em viveiro e a campo do alto vigor dos porta-enxertos para pereira 'Taiwan Nashi-C' (Pyrus calleryana Decne e 'Taiwan Mamenashi' (Pyrus betulifolia Bunge, objetivou-se, neste trabalho, verificar o crescimento de cultivares de marmeleiros ('Provence', 'Mendoza Inta-37', 'Portugal', 'Smyrna' e 'Japonês' enxertados sobre esses porta-enxertos, na fase de viveiro. Os marmeleiros foram enxertados pelo método de garfagem em mudas dos porta-enxertos 'Japonês', 'Taiwan Nashi-C' e 'Taiwan Mamenashi', mantidas em sacos plásticos (capacidade de 3 L de substrato, no período hibernal. Foram utilizados garfos com três gemas, coletadas de plantas-matrizes do Instituto Agronômico (IAC. O experimento foi realizado em viveiro telado (50% de luminosidade, sendo avaliados o comprimento e diâmetro do enxerto aos 60, 90, 120 e 150 dias após a realização da enxertia e a porcentagem de garfos brotados na última avaliação. Os porta-enxertos orientais de pereira apresentaram bons resultados na fase de viveiro, com 'Taiwan Nashi-C' destacando-se como porta-enxerto para os marmeleiros 'Smyrna' e 'Mendoza Inta-37', 'Taiwan Mamenashi' para o marmeleiro 'Smyrna' e 'Japonês' para o mesmo.The quince tree has always been commercially propagated by cuttings. Due to the low vigor, mainly in the first years of the orchard, a series of works was developed in Brazil in order to enable the use of the Japanese quince tree (Chaenomeles sinensis Koehne as a rootstock. The results were

  8. Morphological Characterization of Cherry Rootstock Candidates Selected from Central and East Black Sea Regions in Turkey

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    Aysen Koc

    2013-01-01

    Full Text Available The use of rootstocks particularly for sweet cherry cultivars is of great importance for successful and sustainable production. Choosing the right cherry rootstocks is just as important as choosing the right cultivar. In this study, 110 sweet cherry, 30 sour cherry, and 41 mahaleb types displaying rootstock potential for sweet cherry cultivars were selected from Central and East Black Sea Regions in Turkey. The morphologic characteristics of the studied genotypes were compared with the standard clonal rootstocks PHL-A, MaxMa 14, Montmorency, Weiroot 158, Gisela 5, Gisela 6, and SL 64. A total of 42 morphological UPOV characteristics were evaluated in the selected genotypes and clonal rootstocks. The obtained data were analyzed by using principal component analysis and it revealed that eigenvalues of the first 3 components were able to represent 36.43% of total variance. The most significant positive correlations of the plant vigor were determined with leaf blade length and petiole thickness. According to the diversity analysis of coefficients, the 05 C 002 and 08 C 039 genotypes were identified as being similar (6.66, while the 05 C 002 and 55 S 012 genotypes were determined as the most distant genotypes (325.84 in terms of morphology.

  9. INFLUENCE OF ROOTSTOCKS ON Fusarium WILT, NEMATODE INFESTATION, YIELD AND FRUIT QUALITY IN WATERMELON PRODUCTION

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    Juan Carlos Álvarez-Hernández

    2015-08-01

    Full Text Available Cucurbita maxima x Cucurbita moschata rootstock are used to prevent infection with Fusarium oxysporum f. sp. niveum in watermelon production; however, this rootstock is not effective against nematode attack. Because of their vigor, the grafted plants can be planted at lower plant densities than the non-grafted plants. The tolerance to Fusarium oxysporum f. sp. niveum and Meloidogyne incognita was assessed in watermelon plants grafted onto a hybrid of Citrullus lanatus cv Robusta or the Cucurbita maxima x Cucurbita moschata cv Super Shintoza rootstocks. The densities of plants were 2083 and 4166 plants ha-1. Non-grafted watermelons were the controls. The Crunchy Red and Sangría watermelon cultivars were used as the scions, it the latter as a pollinator. The experiments were performed for two production cycles in soils infested with Fusarium oxysporum f. sp. niveum and Meloidogyne incognita. The incidence of Fusarium oxysporum f. sp. niveum was significantly greater in the non-grafted than in the grafted plants. The grafted plants presented similar resistance to Fusarium regardless of the rootstock. The root-knot galling index for Meloidogyne incognita was significantly lower in plants grafted onto Citrullus lanatus cv Robusta than onto the other rootstock. The yields of plants grafted onto Citrullus lanatus cv Robusta grown at both plant densities were significantly higher than in the other treatments.

  10. Physiological characterization of grapevine rootstocks grown in soil with increasing zinc doses

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    Jovani Zalamena

    2015-10-01

    Full Text Available ABSTRACTThis study aimed to evaluate the performance of grapevine rootstocks under increasing levels of Zn in the soil and to identify physiological variables that can be used as indicators of excess of Zn in the soil. The rootstocks SO4, Paulsen1103, IAC572, IAC313 and 420A were grown in pots containing soil, which received Zn doses of 0, 20, 40, 80 or 160 mg kg-1 of soil. Dry matter (DM, Zn content in shoots and roots, chlorophyll index, initial fluorescence (Fo, maximum fluorescence (Fm, maximum quantum yield of photosystem II (Fv/Fm, effective quantum yield of photosystem II (Y-II and non-photochemical quenching (NPQ were evaluated. The increase of Zn levels in the soil decreased DM in all rootstocks, and IAC572 was superior to the others. The variation in the indices of chlorophyll a and b had little expression in relation the soil Zn levels, but allowed identifying that the rootstocks Paulsen 1103, 420A and SO4 are sensitive to Zn toxicity and that IAC572 and IAC313 were not sensitive to the tested levels. Fluorescence analysis showed a negative effect of Zn contents on the variables Fo, Fm, Y-II and NPQ in all rootstocks, which proved to be good indicators of Zn phytotoxicity.

  11. Alternative methods for the control of postharvest citrus diseases.

    Science.gov (United States)

    Talibi, I; Boubaker, H; Boudyach, E H; Ait Ben Aoumar, A

    2014-07-01

    The postharvest diseases of citrus fruit cause considerable losses during storage and transportation. These diseases are managed principally by the application of synthetic fungicides. However, the increasing concern for health hazards and environmental pollution due to chemical use has required the development of alternative strategies for the control of postharvest citrus diseases. Management of postharvest diseases using microbial antagonists, natural plant-derived products and Generally Recognized As Safe compounds has been demonstrated to be most suitable to replace the synthetic fungicides, which are either being banned or recommended for limited use. However, application of these alternatives by themselves may not always provide a commercially acceptable level of control of postharvest citrus diseases comparable to that obtained with synthetic fungicides. To provide more effective disease control, a multifaceted approach based on the combination of different postharvest treatments has been adopted. Actually, despite the distinctive features of these alternative methods, several reasons hinder the commercial use of such treatments. Consequently, research should emphasize the development of appropriate tools to effectively implement these alternative methods to commercial citrus production.

  12. Comportamento da laranjeira Piralima sobre Poncirus trifoliata com variações na altura de enxertia Behaviour of Piralima orange on Poncirus trifoliata rootstock as a function of budding height

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    V.R. Sampaio

    1994-04-01

    Full Text Available Pesquisou-se a combinação de laranjeira Piralima, Citrus sinensis (L. Osb. sobre Poncirus trifoliata (L. Raf. fazendo-se variações nas alturas das enxertias, com operações efetuadas a zero, dez, vinte e quarenta centímetros de altura. Avaliações realizadas após seis anos e meio de implantação do experimento permitiram as seguintes conclusões: 1 as alturas das enxertias afetaram o desenvolvimento global das plantas, com as enxertias mais altas reforçando o efeito ananicante do Poncirus trifoliata; 2 as diferentes alturas de enxertia não afetaram as produções de frutos das três primeiras produções comerciais. Na quarta colheita surgiu diferença entre os tratamentos extremos, com maiores produções acontecendo para plantas enxertadas próximas ao solo; 3 o Poncirus trifoliata induziu características ananicantes às copas e as constantes boas produções de frutos de bom tamanho. Mostrou-se ser porta-enxerto interessante para o cultivar Piralima.The combination Poncirus trifoliata x Piralima acidless orange was studied as a function of the budding height, from zero to forty centimeters. After six and half years of evaluations the results led to the following conclusions: 1 variation in the budding height affected the plant global development: the higher was the budding height, the more intense was the Poncirus trifoliata dwarf effect. 2 variation in budding height did not affect orange yield during the first three commercial harvests. Difference occurred in the fourth harvest, between the extreme treatments, with larger yields for plants budded near to the soil. 3 Poncirus trifoliata induced dwarf characteristics to 'Piralima' stock as well as regular and good yield along the years, and the fruits were classified as high grade. Poncirus trifoliata showed to be an interesting rootstock for the cultivar Piralima.

  13. Hybrid Origins of Citrus Varieties Inferred from DNA Marker Analysis of Nuclear and Organelle Genomes

    Science.gov (United States)

    Kitajima, Akira; Nonaka, Keisuke; Yoshioka, Terutaka; Ohta, Satoshi; Goto, Shingo; Toyoda, Atsushi; Fujiyama, Asao; Mochizuki, Takako; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu

    2016-01-01

    Most indigenous citrus varieties are assumed to be natural hybrids, but their parentage has so far been determined in only a few cases because of their wide genetic diversity and the low transferability of DNA markers. Here we infer the parentage of indigenous citrus varieties using simple sequence repeat and indel markers developed from various citrus genome sequence resources. Parentage tests with 122 known hybrids using the selected DNA markers certify their transferability among those hybrids. Identity tests confirm that most variant strains are selected mutants, but we find four types of kunenbo (Citrus nobilis) and three types of tachibana (Citrus tachibana) for which we suggest different origins. Structure analysis with DNA markers that are in Hardy–Weinberg equilibrium deduce three basic taxa coinciding with the current understanding of citrus ancestors. Genotyping analysis of 101 indigenous citrus varieties with 123 selected DNA markers infers the parentages of 22 indigenous citrus varieties including Satsuma, Temple, and iyo, and single parents of 45 indigenous citrus varieties, including kunenbo, C. ichangensis, and Ichang lemon by allele-sharing and parentage tests. Genotyping analysis of chloroplast and mitochondrial genomes using 11 DNA markers classifies their cytoplasmic genotypes into 18 categories and deduces the combination of seed and pollen parents. Likelihood ratio analysis verifies the inferred parentages with significant scores. The reconstructed genealogy identifies 12 types of varieties consisting of Kishu, kunenbo, yuzu, koji, sour orange, dancy, kobeni mikan, sweet orange, tachibana, Cleopatra, willowleaf mandarin, and pummelo, which have played pivotal roles in the occurrence of these indigenous varieties. The inferred parentage of the indigenous varieties confirms their hybrid origins, as found by recent studies. PMID:27902727

  14. Hybrid Origins of Citrus Varieties Inferred from DNA Marker Analysis of Nuclear and Organelle Genomes.

    Science.gov (United States)

    Shimizu, Tokurou; Kitajima, Akira; Nonaka, Keisuke; Yoshioka, Terutaka; Ohta, Satoshi; Goto, Shingo; Toyoda, Atsushi; Fujiyama, Asao; Mochizuki, Takako; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu

    2016-01-01

    Most indigenous citrus varieties are assumed to be natural hybrids, but their parentage has so far been determined in only a few cases because of their wide genetic diversity and the low transferability of DNA markers. Here we infer the parentage of indigenous citrus varieties using simple sequence repeat and indel markers developed from various citrus genome sequence resources. Parentage tests with 122 known hybrids using the selected DNA markers certify their transferability among those hybrids. Identity tests confirm that most variant strains are selected mutants, but we find four types of kunenbo (Citrus nobilis) and three types of tachibana (Citrus tachibana) for which we suggest different origins. Structure analysis with DNA markers that are in Hardy-Weinberg equilibrium deduce three basic taxa coinciding with the current understanding of citrus ancestors. Genotyping analysis of 101 indigenous citrus varieties with 123 selected DNA markers infers the parentages of 22 indigenous citrus varieties including Satsuma, Temple, and iyo, and single parents of 45 indigenous citrus varieties, including kunenbo, C. ichangensis, and Ichang lemon by allele-sharing and parentage tests. Genotyping analysis of chloroplast and mitochondrial genomes using 11 DNA markers classifies their cytoplasmic genotypes into 18 categories and deduces the combination of seed and pollen parents. Likelihood ratio analysis verifies the inferred parentages with significant scores. The reconstructed genealogy identifies 12 types of varieties consisting of Kishu, kunenbo, yuzu, koji, sour orange, dancy, kobeni mikan, sweet orange, tachibana, Cleopatra, willowleaf mandarin, and pummelo, which have played pivotal roles in the occurrence of these indigenous varieties. The inferred parentage of the indigenous varieties confirms their hybrid origins, as found by recent studies.

  15. Transcriptional regulation of lycopene metabolism mediated by rootstock during the ripening of grafted watermelons.

    Science.gov (United States)

    Kong, Qiusheng; Yuan, Jingxian; Gao, Lingyun; Liu, Peng; Cao, Lei; Huang, Yuan; Zhao, Liqiang; Lv, Huifang; Bie, Zhilong

    2017-01-01

    Rootstocks have comprehensive effects on lycopene accumulation in grafted watermelon fruits. However, little is known about lycopene metabolic regulation in grafted watermelon. To address this problem, parallel changes in lycopene contents and the expression of its metabolic genes were analyzed during the fruit ripening of nongrafted watermelon and watermelon grafted onto bottle gourd, pumpkin, and wild watermelon. Results showed that rootstocks mediated the transcriptional regulations of lycopene accumulation in different ways. Bottle gourd and wild watermelon promoted lycopene accumulation in grafted watermelon fruits by upregulating the biosynthetic genes phytoene synthase (PSY) and ζ-carotene desaturase (ZDS), and downregulating the catabolic genes β-carotene hydroxylase (CHYB), zeaxanthin epoxidase (ZEP), 9-cis-epoxycarotenoid dioxygenase (NCED), and carotenoid cleavage dioxygenase (CCD). However, pumpkin did not affect lycopene accumulation by upregulating both biosynthetic and catabolic genes. The rootstock-dependent characteristic of lycopene accumulation in grafted watermelon fruits provided an alternative model for investigating lycopene metabolic regulation.

  16. NMR Spectroscopy Identifies Metabolites Translocated from Powdery Mildew Resistant Rootstocks to Susceptible Watermelon Scions.

    Science.gov (United States)

    Mahmud, Iqbal; Kousik, Chandrasekar; Hassell, Richard; Chowdhury, Kamal; Boroujerdi, Arezue F

    2015-09-16

    Powdery mildew (PM) disease causes significant loss in watermelon. Due to the unavailability of a commercial watermelon variety that is resistant to PM, grafting susceptible cultivars on wild resistant rootstocks is being explored as a short-term management strategy to combat this disease. Nuclear magnetic resonance-based metabolic profiles of susceptible and resistant rootstocks of watermelon and their corresponding susceptible scions (Mickey Lee) were compared to screen for potential metabolites related to PM resistance using multivariate principal component analysis. Significant score plot differences between the susceptible and resistant groups were revealed through Mahalanobis distance analysis. Significantly different spectral buckets and their corresponding metabolites (including choline, fumarate, 5-hydroxyindole-3-acetate, and melatonin) have been identified quantitatively using multivariate loading plots and verified by volcano plot analyses. The data suggest that these metabolites were translocated from the powdery mildew resistant rootstocks to their corresponding powdery mildew susceptible scions and can be related to PM disease resistance.

  17. Precocious flowering of juvenile citrus induced by a viral vector based on Citrus leaf blotch virus: a new tool for genetics and breeding.

    Science.gov (United States)

    Velázquez, Karelia; Agüero, Jesús; Vives, María C; Aleza, Pablo; Pina, José A; Moreno, Pedro; Navarro, Luis; Guerri, José

    2016-10-01

    The long juvenile period of citrus trees (often more than 6 years) has hindered genetic improvement by traditional breeding methods and genetic studies. In this work, we have developed a biotechnology tool to promote transition from the vegetative to the reproductive phase in juvenile citrus plants by expression of the Arabidopsis thaliana or citrus FLOWERING LOCUS T (FT) genes using a Citrus leaf blotch virus-based vector (clbvINpr-AtFT and clbvINpr-CiFT, respectively). Citrus plants of different genotypes graft inoculated with either of these vectors started flowering within 4-6 months, with no alteration of the plant architecture, leaf, flower or fruit morphology in comparison with noninoculated adult plants. The vector did not integrate in or recombine with the plant genome nor was it pollen or vector transmissible, albeit seed transmission at low rate was detected. The clbvINpr-AtFT is very stable, and flowering was observed over a period of at least 5 years. Precocious flowering of juvenile citrus plants after vector infection provides a helpful and safe tool to dramatically speed up genetic studies and breeding programmes.

  18. Candidate gene markers for Candidatus Liberibacter asiaticus for detecting citrus greening disease.

    Science.gov (United States)

    Nageswara-Rao, Madhugiri; Irey, Mike; Garnsey, Stephen M; Gowda, Siddarame

    2013-06-01

    Citrus Huanglongbing (HLB) also known as citrus greening is one of the most devastating diseases of citrus worldwide. The disease is caused by Candidatus Liberibacter bacterium, vectored by the psyllid Diaphorina citri Kuwayama and Trioza erytreae Del Guercio. Citrus plants infected by the HLB bacterium may not show visible symptoms sometimes for years following infection. The aim of this study was to develop effective gene-specific primer pairs for polymerase chain reaction based method for quick screening of HLB disease. Thirty-two different gene-specific primer pairs, across the Ca. Liberibacter asiaticus genome, were successfully developed. The possibility of these primer pairs for cross-genome amplification across 'Ca. Liberibacter africanus' and 'Ca. Liberibacter americanus' were tested. The applicability of these primer pairs for detection and differentiation of Ca Liberibacter spp. is discussed.

  19. Candidate gene markers for Candidatus Liberibacter asiaticus for detecting citrus greening disease

    Indian Academy of Sciences (India)

    Madhugiri Nageswara-Rao; Mike Irey; Stephen M Garnsey; Siddarame Gowda

    2013-06-01

    Citrus Huanglongbing (HLB) also known as citrus greening is one of the most devastating diseases of citrus worldwide. The disease is caused by Candidatus Liberibacter bacterium, vectored by the psyllid Diaphorina citri Kuwayama and Trioza erytreae Del Guercio. Citrus plants infected by the HLB bacterium may not show visible symptoms sometimes for years following infection. The aim of this study was to develop effective gene-specific primer pairs for polymerase chain reaction based method for quick screening of HLB disease. Thirty-two different gene-specific primer pairs, across the Ca. Liberibacter asiaticus genome, were successfully developed. The possibility of these primer pairs for cross-genome amplification across `Ca. Liberibacter africanus’ and `Ca. Liberibacter americanus’ were tested. The applicability of these primer pairs for detection and differentiation of Ca Liberibacter spp. is discussed.

  20. 78 FR 63369 - Citrus Canker, Citrus Greening, and Asian Citrus Psyllid; Interstate Movement of Regulated...

    Science.gov (United States)

    2013-10-24

    ... infected plants, which render the fruit unmarketable, and cause infected fruit to drop from the trees... of the fruit, and can kill trees. Once infected, there is no cure for a tree with citrus greening. In... disease that is caused by a complex of Xanthomonas spp. bacteria and that affects plants and plant...

  1. Field ID guide to citrus relative hosts of Asian citrus psyllid & Huanglongbing

    Science.gov (United States)

    The Rutaceae family of plants includes not only species within the genus Citrus, but also several other genera and species that may not be easily recognized as having any relationship to citrus at all. However, many of these citrus relatives are used for ornamental, culinary, or religious purposes. ...

  2. Larvicidal Activity of Citrus Limonoids against Aedes albopictus Larvae

    Directory of Open Access Journals (Sweden)

    Hazrat Bilal

    2012-12-01

    Full Text Available Background: Development of insecticide resistance occurred due to the continuous and misuse of synthetic insecticidestherefore, the recent study was conducted to explore eco-friendly plant extracts that have some potential to suppressmosquito larval population.Methods: WHO recommended mosquito larval bioassay method for insecticide was used while for the analysis of citrus oils for limonin and nomilin content HPLC was used.Results: Among the two citrus cultivars tested as larvicide against Aedes albopictus, valencia late (Citrus sinensis wasthe best in terms of LC50 (297 ppm, % mortality (97% and LT50 (18.49 hours then freutrall early (Citrus reticulatewith LC50 (377.4 ppm, % mortality (88% and LT50 (31 hours, While nomilin gave lowest LC50 (121.04 ppm than limonin (382.22 ppm after 72 hours of exposure. Valencia late also had more limonin and nomilin (377 μg/ml and 21.19 μg/ml than freutrall early (5.29 μg/ml and 3.89 μg/ml respectively.Conclusion: Valencia late showed best results in term of LC50, LT50 and percentage mortality against Aedes albopictus as it has more amount of nomilin then freutrall early, however further evaluation in the field conditions is required.

  3. Larvicidal Activity of Citrus Limonoids against Aedes Albopictus Larvae

    Directory of Open Access Journals (Sweden)

    Hazrat Bilal

    2012-12-01

    Full Text Available Background: Development of insecticide resistance occurred due to the continuous and misuse of synthetic insecti­cides therefore, the recent study was conducted to explore eco-friendly plant extracts that have some potential to sup­press mosquito larval population.Methods: World Health Organization recommended mosquito larval bioassay method for insecticide was used while for the analysis of citrus oils for limonin and nomilin content HPLC was used.Results: Among the two citrus cultivars tested as larvicide against Aedes albopictus, valencia late (Citrus sinensis was the best in terms of LC50 (297 ppm, % mortality (97% and LT50 (18.49 hours then freutrall early (Citrus reticulate with LC50 (377.4 ppm, % mortality (88% and LT50 (31 hours, While nomilin gave lowest LC­­50 (121.04 ppm than limonin (382.22 ppm after 72 hours of exposure. Valencia late also had more limonin and nomilin (377 µg/ml and 21.19 µg/ml than freutrall early (5.29 µg/ml and 3.89 µg/ml respectively.Conclusion: Valencia late showed best results in term of LC50, LT50 and percentage mortality against Aedes albopictus as it has more amount of nomilin then freutrall early, however further evaluation in the field conditions is required

  4. Root Proteomic Analysis of Grapevine Rootstocks Inoculated with Rhizophagus irregularis and Fusarium oxysporum f. sp. herbemontis

    Directory of Open Access Journals (Sweden)

    Elisa Vilvert

    Full Text Available ABSTRACT Grapevine decline and death caused by the pathogenic fungus Fusarium oxysporum f. sp. herbemontis is among the main phytosanitary problem for viticulture in southern Brazil. The eradication of infected plants is presently the most common procedure for disease control in vineyards. Inoculation with arbuscular mycorrhizal fungi is an option to reduce or neutralize the negative impacts of soil pathogenic microorganisms, but the mechanisms of plant response involved in this process are not yet completely elucidated. In order to better understand these mechanisms, an experiment was carried out to identify proteins related to plant defence induced by the mycorrhizal fungus after infection with the pathogenic fungus. We used the grapevine rootstocks SO4 and R110 (susceptible and resistant to the pathogenic fungus, respectively inoculated or not inoculated with the mycorrhizal fungus Rhizophagus irregularis, and inoculated or not inoculated with Fusarium oxysporum f. sp. herbemontis. Growth of the rootstocks’ shoot and root and presence of pathogenic symptoms were evaluated. The protein profiles of roots were characterized by two-dimensional electrophoresis and proteins were identified using mass spectrometry. The grapevine rootstocks inoculated with R. irregularis had higher biomass production and lower level of pathogenic symptoms. The R110 rootstock differentially accumulated 73 proteins, while SO4 accumulated 59 proteins. Nine plant-defence proteins were expressed by SO4 rootstock, and six were expressed by R110 rootstock plants. The results confirm the effect of mycorrhizal fungi in plant growth promotion and their potential for biological control against soil pathogenic fungus. Protein expression is dependent on rootstock characteristics and on the combination of plant material with the fungi.

  5. Estimation Of Productive Value Of Czech Origin Scab-Resistant Apple Cultivars On Different Rootstocks

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    Sosna Ireneusz

    2014-12-01

    Full Text Available Apple cultivars resistant to scab are suitable for the conventional and organic cultivation. Rootstocks impact on the growth of trees, yield and fruit quality of scab-resistant cultivars were examined in the experiment conducted at Fruit Experimental Station - Samotwór near Wrocław, during the years 1998-2008. In the spring of 1998, the trees of five Czech origin scab-resistant apple cultivars ‘Rosana’, ‘Rubinola’, ‘Rajka’, ‘Goldstar’ and ‘Topaz’ each on M.9, P2, P60, P16 and P22 rootstocks were planted at a spacing of 3.5 × 1.2 m (2380 trees per hectare. The results of 11-year-long studies showed that ‘Rubinola’ and ‘Rajka’ were characterised by the strongest vigour, while ‘Rosana’ grew much weaker. Significant differences in the cumulative yield were not observed between cultivars, but rootstocks influenced cropping instantly. Trees on rootstock P60 had biggest cross-section area and canopy volume, and the highest cumulative yield. Fruit weight was highest from trees on M9 and P60. ‘Topaz’ and ‘Rosana’ formed significantly lightest fruits and ‘Goldstar’ the heaviest. Trees on the super-dwarfing P22 rootstock grew and yielded very weakly and produced very small fruits. The greatest susceptibility to powdery mildew (Podosphaera leucotricha was observed in ‘Topaz’ and ‘Rajka’. ‘Rubinola’ has the best potential for organic cultivation, especially on dwarfing rootstocks.

  6. Reação de híbridos somáticos de citros à infecção por Phytophthora nicotianae Reaction of citrus somatic hybrids to the infection by Phytophthora nicotianae

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    Meire Menezes Bassan

    2010-06-01

    Full Text Available Este trabalho avaliou a resistência à infecção de tronco e de raízes por Phytophthora nicotianae em híbridos somáticos de citros com potencial para serem utilizados como porta-enxertos. Os híbridos somáticos avaliados foram laranja 'Hamlin' (Citrus sinensis + toranja 'Indian Red' (Citrus grandis (plantas 1 e 2 e laranja 'Hamlin' (C. sinensis + toranja 'Singapura' (C. grandis. Plantas de limão 'Cravo' (Citrus limonia, laranja 'Caipira' (C. sinensis, laranja-azeda (C. aurantium e Poncirus trifoliata 'Davis A' (Poncirus trifoliata foram utilizadas como plantas-controle devido à reação conhecida à infecção pelo patógeno. Avaliações realizadas entre 30 e 60 dias após as inoculações com o patógeno incluíram o comprimento das lesões no tronco e a massa seca do sistema radicular nas plantas avaliadas. O híbrido somático laranja 'Hamlin' + toranja 'Indian Red' (planta 1 mostrou-se tolerante a P. nicotianae, indicando potencial para continuidade nas suas avaliações como porta-enxerto para citros.This study aimed to evaluate the resistance to trunk and root infection by Phytophthora nicotianae in citrus somatic hybrids with potential to be utilized as rootstocks. The somatic hybrids evaluated were 'Hamlin' sweet orange (Citrus sinensis + 'Indian Red' pummelo (Citrus grandis (plants 1 and 2, and 'Hamlin' sweet orange (C. sinensis + 'Singapura' pummelo (C. grandis. Plants of 'Rangpur' lime (Citrus limonia, 'Caipira' sweet orange (C. sinensis, sour orange (C. aurantium, and Poncirus trifoliata 'Davis A' (Poncirus trifoliata were used as control due to their known reaction to the pathogen. Evaluations performed between 30 and 60 days after pathogen inoculation included the length of trunk lesions, and root dry mass of the root system of evaluated plants. The somatic hybrid 'Hamlin' sweet orange + 'Indian Red' pummelo (plant 1 was tolerant to P. nicotianae, indicating potential to be further evaluated as a rootstock.

  7. Asian citrus psyllid RNAi pathway : RNAi evidence

    OpenAIRE

    Taning, Clauvis N. T.; Andrade, Eduardo C.; Hunter, Wayne B.; Olivier Christiaens; Guy Smagghe

    2016-01-01

    Diaphorina citri, known as the Asian citrus psyllid, is an important pest of citrus because it transmits a phloem-limited bacteria strongly implicated in huanglongbing (citrus greening disease). Emerging biotechnologies, such as RNA interference, could provide a new sustainable and environmentally friendly strategy for the management of this pest. In this study, genome and functional analysis were performed to verify whether the RNAi core genes are present in the Asian psyllid genome and if t...

  8. Complete Chloroplast Genome Sequence of Omani Lime (Citrus aurantiifolia) and Comparative Analysis within the Rosids

    OpenAIRE

    Huei-Jiun Su; Hogenhout, Saskia A.; Al-Sadi, Abdullah M.; Chih-Horng Kuo

    2014-01-01

    The genus Citrus contains many economically important fruits that are grown worldwide for their high nutritional and medicinal value. Due to frequent hybridizations among species and cultivars, the exact number of natural species and the taxonomic relationships within this genus are unclear. To compare the differences between the Citrus chloroplast genomes and to develop useful genetic markers, we used a reference-assisted approach to assemble the complete chloroplast genome of Omani lime (C....

  9. Citrus fruits as a treasure trove of active natural metabolites that potentially provide benefits for human health.

    Science.gov (United States)

    Lv, Xinmiao; Zhao, Siyu; Ning, Zhangchi; Zeng, Honglian; Shu, Yisong; Tao, Ou; Xiao, Cheng; Lu, Cheng; Liu, Yuanyan

    2015-01-01

    Citrus fruits, which are cultivated worldwide, have been recognized as some of the most high-consumption fruits in terms of energy, nutrients and health supplements. What is more, a number of these fruits have been used as traditional medicinal herbs to cure diseases in several Asian countries. Numerous studies have focused on Citrus secondary metabolites as well as bioactivities and have been intended to develop new chemotherapeutic or complementary medicine in recent decades. Citrus-derived secondary metabolites, including flavonoids, alkaloids, limonoids, coumarins, carotenoids, phenolic acids and essential oils, are of vital importance to human health due to their active properties. These characteristics include anti-oxidative, anti-inflammatory, anti-cancer, as well as cardiovascular protective effects, neuroprotective effects, etc. This review summarizes the global distribution and taxonomy, numerous secondary metabolites and bioactivities of Citrus fruits to provide a reference for further study. Flavonoids as characteristic bioactive metabolites in Citrus fruits are mainly introduced.

  10. Natural products for cancer-targeted therapy: citrus flavonoids as potent chemopreventive agents.

    Science.gov (United States)

    Meiyanto, Edy; Hermawan, Adam; Anindyajati

    2012-01-01

    Targeted therapy has been a very promising strategy of drug development research. Many molecular mechanims of diseases have been known to be regulated by abundance of proteins, such as receptors and hormones. Chemoprevention for treatment and prevention of diseases are continuously developed. Pre-clinical and clinical studies in chemoprevention field yielded many valuable data in preventing the onset of disease and suppressing the progress of their growth, making chemoprevention a challenging and a very rational strategy in future researches. Natural products being rich of flavonoids are those fruits belong to the genus citrus. Ethanolic extract of Citrus reticulata and Citrus aurantiifolia peels showed anticarcinogenic, antiproliferative, co-chemotherapeutic and estrogenic effects. Several examples of citrus flavonoids that are potential as chemotherapeutic agents are tangeretin, nobiletin, hesperetin, hesperidin, naringenin, and naringin. Those flavonoids have been shown to possess inhibition activity on certain cancer cells' growth through various mechanisms. Moreover, citrus flavonoids also perform promising effect in combination with several chemotherapeutic agents against the growth of cancer cells. Some mechanisms involved in those activities are through cell cycle modulation, antiangiogenic effect, and apoptosis induction. Previous studies showed that tangeretin suppressed the growth of T47D breast cancer cells by inhibiting ERK phosphorylation. While in combination with tamoxifen, doxorubicin, and 5-FU, respectively, it was proven to be synergist on several cancer cells. Hesperidin and naringenin increased cytotoxicitity of doxorubicin on MCF-7 cells and HeLa cells. Besides, citrus flavonoids also performed estrogenic effect in vivo. One example is hesperidin having the ability to decrease the concentration of serum and hepatic lipid and reduce osteoporosis of ovariectomized rats. Those studies showed the great potential of citrus fruits as natural product

  11. Integrated systems biology analysis of transcriptomes reveals candidate genes for acidity control in developing fruits of sweet orange (Citrus sinensis L. Osbeck

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    Dingquan eHuang

    2016-04-01

    Full Text Available Organic acids, such as citrate and malate, are important contributors for the sensory traits of fleshy fruits. Although their biosynthesis has been illustrated, regulatory mechanisms of acid accumulation remain to be dissected. To provide transcriptional architecture and identify candidate genes for citrate accumulation in fruits, we have selected for transcriptome analysis four varieties of sweet orange (Citrus sinensis L. Osbeck with varying fruit acidity, Succari (acidless, Bingtang (low acid, and Newhall and Xinhui (normal acid. Fruits of these varieties at 45 days post anthesis (DPA, which corresponds to Stage I (cell division, had similar acidity, but they displayed differential acid accumulation at 142 DPA (Stage II, cell expansion. Transcriptomes of fruits at 45 and 142 DPA were profiled using RNA sequencing and analyzed with three different algorithms (Pearson correlation, gene coexpression network and surrogate variable analysis. Our network analysis shows that the acid-correlated genes belong to three distinct network modules. Several of these candidate fruit acidity genes encode regulatory proteins involved in transport (such as AH10, degradation (such as APD2 and transcription (such as AIL6 and act as hubs in the citrate accumulation gene networks. Taken together, our integrated systems biology analysis has provided new insights into the fruit citrate accumulation gene network and led to the identification of candidate genes likely associated with the fruit acidity control.

  12. Bioactive molecules as authenticity markers of Italian Chinotto (Citrus×myrtifolia) fruits and beverages.

    Science.gov (United States)

    Protti, Michele; Valle, Francesco; Poli, Ferruccio; Raggi, Maria Augusta; Mercolini, Laura

    2015-02-01

    Chinotto (Citrus×myrtifolia) is a uncommon fruit belonging to the Citrus genus, mainly cultivated in small areas of the Italian territory, where the main use concerns the eponymous drink, marketed with the name of "Chinotto". The lack of information about this fruit highlights the usefulness of nutraceutical compound characterization, as well as the need to identify genuineness markers in derived commercial products. An analytical strategy based on SPE-HPLC-F was developed to identify and quantify different bioactive compounds in Chinotto (Citrus×myrtifolia) fruits and commercial beverages. The method was fully validated and successfully applied to the analysis of nutraceutical compounds in Chinotto fruits of Italian origin and in some Chinotto-based beverages, granting reliable and consistent data. The obtained results provided preliminary key information about the bioactive profiling of Citrus×myrtifolia and proved the suitability of the selected compounds as authenticity markers of derived commercial soft drinks.

  13. Produtividade e qualidade dos frutos da laranjeira 'Pêra' clone IAC em 16 porta-enxertos na região de Bebedouro-SP Yield and fruit quality of 'Pêra' sweet orange clone IAC on 16 rootstocks in Bebedouro region, State of São Paulo, Brazil

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    Eduardo Sanches Stuchi

    2004-08-01

    Full Text Available Avaliou-se a influência de 16 porta-enxertos na produtividade, nas características físicas e químicas (sólidos solúveis totais-°Brix; acidez; ratio; porcentagem de suco; índice tecnológico e tamanho dos frutos dos frutos da laranjeira 'Pêra' [Citrus sinensis (L. Osbeck] e na incidência e severidade da clorose variegada dos citros (CVC. O plantio do experimento foi realizado em julho de 1993, com espaçamento de 6,0 m entre linhas e 3,5 m entre plantas (476 plantas/ha. O experimento foi conduzido sem irrigação. O delineamento experimental foi em blocos ao acaso, duas plantas por parcela, três repetições e 16 tratamentos, constituídos pelas seguintes cultivares porta-enxertos: tangerineira 'Sun Chu Sha Kat' (Citrus reticulata Blanco, tangerineira 'Pectinífera' (C. reticulata, 'Shekwasha' (C. depressa Hayata, tangerineira 'Pectinífera/Shekwasha' (C. depressa Hayata, tangerineira 'Batangas' (C. reticulata, tangerineira 'Oneco' (C. reticulata, citrangor [citrange (Poncirus trifoliata Raf. x C. sinensis x C. sinensis], citrandarin [C.sunki hort. Ex Tanaka x Poncirus trifoliata (L. Raf. cv. English, tangerineira 'Sunki' (C. sunki, tangerineira 'Suen-Kat' (C. sunki, tangerineira 'Nasnaran' (C. amblycarpa Ochse, tangerineira 'Venezuela' (C. reticulata, tangerineira Heen Naran (C. lycopersicaeformis hort. ex Tan. , limoeiro 'Cravo' (C. limonia Osbeck x tangerineira 'Cleópatra' (C. reshni hort ex Tanaka, limoeiro 'Cravo' (C. limonia, tangerineira 'Cleópatra' (C. reshni. A intensidade da clorose variegada dos citros variou em função dos porta-enxertos e não se relacionou com a produção de frutos até a quarta safra. Os porta-enxertos estudados, com exceção da tangerineira Nasnaran, proporcionaram qualidade e produções iniciais de frutos similares aos do limoeiro 'Cravo'.An experiment was set up in July 1993, at Bebedouro city, São Paulo state, Brazil, aiming to evaluate the rootstock influence on the yield and several physical

  14. In vitro organogenesis in some citrus species

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    Evandro Henrique Schinor

    2011-06-01

    Full Text Available In vitro organogenesis of Citrus was studied for the genotypes Citrus sinensis cv. 'Natal', C. limonia, C. volkameriana, and C. aurantium, with the use of epicotyl segments-derived explants, cultured in MT salts and vitamins medium supplemented with different concentrations of 6-benzylaminopurine (BAP - 0.0; 0.5; 1.0; 1.5 or 2.0 mg L-1. For the recalcitrant genotypes C. limonia and C. aurantium the in vitro organogenesis was also studied with internodal segments-derived explants, cultured in MT salts and vitamins medium supplemented with 0; 0.5; 1.0; 2.0, or 4.0 mg L-1 of BAP. The efficiency of culture medium supplementation with the combination of BAP (0.0; 1.0, or 2.0 mg L-1 and NAA (1-naphthaleneacetic acid - 0.0; 0.3, or 0.5 mg L-1 in the development of adventitious shoots was evaluated for C. aurantium. Culture medium supplementation with BAP is not essential for the adventitious shoots development in the four genotypes studied when epicotyl segments-derived explants are used. In general, culture media supplementation with BAP decreased the percentage of responsive explants excepted for C. sinensis cv. 'Natal' and C. limonia when the concentrations of 1.5 and 2.0 mg/L were used. The presence of cytokinin, in concentrations up to 2 mg/L, stimulated the in vitro organogenesis when internodal segments-derived explants were used for C. limonia and C. aurantium. For C. aurantium no adventitious shoots developed in explants (internodal segments cultured in basal culture medium, without BAP supplementation. Although no statistic differences could be detected, culture media supplementation with the combination of BAP and NAA favored the development of adventitious shoots in C. aurantium. The best concentration of NAA varied according to BAP concentration. The results presented herein, show that Citrus in vitro organogenesis depends on the interaction of culture medium composition, explant differentiation level, and genotype.

  15. Effects of grafting with pumpkin rootstock on carbohydrate metabolism in cucumber seedlings under Ca(NO3)2 stress.

    Science.gov (United States)

    Xing, Wen-wen; Li, Lin; Gao, Pan; Li, He; Shao, Qiao-sai; Shu, Sheng; Sun, Jin; Guo, Shi-rong

    2015-02-01

    This study investigated the effects of grafting on the carbohydrate status and the enzymes of carbohydrate metabolism in self-grafted and grafted cucumber seedlings using the salt-tolerant pumpkin rootstock 'Qingzhen 1' (Cucurbita maxima × Cucurbita moschata) under 80 mM Ca(NO3)2 stress for 6 d. The growth of self-grafted seedlings was significantly inhibited after the treatment of Ca(NO3)2 stress, whereas the inhibition of growth was alleviated in pumpkin rootstock-grafted seedlings. Ca(NO3)2 stress increased the contents of the total soluble sugar, sucrose and fructose, but decreased the starch content in rootstock-grafted leaves. However, compared with self-grafted plants, rootstock-grafted seedlings were observed with a higher content of sucrose and total soluble sugar (TSS) under salt stress. Rootstock-grafted seedlings exhibited higher activities of acid invertase (AI), neutral invertase (NI) and phosphate sucrose synthase (SPS) of sucrose metabolism in leaves than that of self-grafted seedlings under salinity. Moreover, the activities of fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) of glycolysis were maintained at a higher level in leaves of rootstock-grafted seedlings after Ca(NO3)2 stress. Additionally, rootstock-grafting decrease the high percentage enhancement of key enzymes gene expression in glycolysis in the scion leaves of cucumber seedlings induced by salt stress. These results suggest that the rootstock-grafting improved salt tolerance, which might play a role in elevated sucrose metabolism and a glycolytic pathway regulated by the pumpkin rootstock.

  16. Comparison of FTIR spectra between Huanglongbing (citrus greening) and other citrus maladies.

    Science.gov (United States)

    Hawkins, Samantha A; Park, Bosoon; Poole, Gavin H; Gottwald, Tim R; Windham, William R; Albano, Joseph; Lawrence, Kurt C

    2010-05-26

    Fourier transform infrared (FTIR) spectroscopy has the ability to quickly identify the presence of specific carbohydrates in plant materials. The presence of the disease huanglongbing (HLB) in the leaves of infected citrus plants has a distinctive spectrum that can be used to distinguish an infected plant from a healthy plant. However, many citrus diseases display similar visible symptoms and are of concern to citrus growers. In this study several citrus diseases (citrus leaf rugose virus, citrus tristeza virus, citrus psorosis virus, and Xanthomonas axonopodis ) and nutrient deficiencies (iron, copper, zinc, manganese, and magnesium) were compared with HLB using FTIR spectroscopy to determine if the spectra alone can be used to identify plants that are infected with HLB instead of another disease. The results indicate that the spectra of some diseases and deficiencies more closely resemble those of apparently healthy plants and some share the carbohydrate transformation that has been seen in the spectra of HLB-infected plants.

  17. DIVERSITY AND ABUNDANCE OF MITES IN A MANDARIN CITRUS ORCHARD IN WEST SUMATRA

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    Affandi Affandi

    2016-10-01

    Full Text Available Some of the most destructive pests in citrus orchards are spider mites. Monitoring prior applied pest control is a standard procedure for integrated pest management (IPM. The study aimed to survey and determine the distribution, abundance, and diversity of phytophagous, predatory, and detritivorous mites at different stages of development of arboreal plant parts, weeds and litter in the citrus orchard. A periodical sampling survey method was conducted on six growth stages of mandarin citrus, weeds and litter of the Indonesian Fruits Research Institute experimental field in Solok, West Sumatra in December 2003 to June 2004. All mites attached on each growth stage of citrus, weeds and litter were trapped and mounted on slide for identification purposes. Identification of the mites was conducted in the Acarology Laboratory, Department of Entomology, University of the Philippines at Los Banos in July-October 2004. The results showed that a very rich mite fauna of 130 species was found in the arboreal parts of citrus crops, weeds and litter below the canopy of the citrus orchard. Among the trophic groups, detritivorous mites were the most abundant, followed by the predators, phytophages, and those unknown feeding habit. Among the habitats, weeds harbored the most mite species followed by litter and arboreal parts of the citrus trees. The flush growth stage had the least diverse mite fauna with index diversity (H’ of 1.27, while the most diverse (H’ = 2.01 was found at fruit development phase II. Result of this research was useful in determining proper time for controlling phytophagous mites. Besides, the result also provides important information on potential predatory mites that can be used as biological control agents. Furthermore, the study implies the importance of maintaining cover crops of weeds and litter beneath the citrus trees as refuge and source of alternate prey for predators which suppressed populations of phytophagous mites.

  18. Green synthesis of gold nanoparticles using Citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) aqueous extract and its characterization

    Science.gov (United States)

    Sujitha, Mohanan V.; Kannan, Soundarapandian

    2013-02-01

    This study reports the biological synthesis of gold nanoparticles by the reduction of HAuCl4 by using citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) juice extract as the reducing and stabilizing agent. A various shape and size of gold nanoparticles were formed when the ratio of the reactants were altered with respect to 1.0 mM chloroauric acid solution. The gold nanoparticles obtained were characterized by UV-visible spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). TEM studies showed the particles to be of various shapes and sizes and particle size ranges from 15 to 80 nm. Selected-area electron diffraction (SAED) pattern confirmed fcc phase and crystallinity of the particles. The X-ray diffraction analysis revealed the distinctive facets (1 1 1, 2 0 0, 2 2 0 and 2 2 2 planes) of gold nanoparticles. Dynamic light scattering (DLS) studies revealed that the average size for colloid gp3 of C. limon, C. reticulata and C. sinensis are 32.2 nm, 43.4 nm and 56.7 nm respectively. The DLS graph showed that the particles size was larger and more polydispersed compared to the one observed by TEM due to the fact that the measured size also includes the bio-organic compounds enveloping the core of the Au NPs. Zeta potential value for gold nanoparticles obtained from colloid gp3 of C. limon, C. reticulata and C. sinensis are -45.9, -37.9 and -31.4 respectively indicating the stability of the synthesized nanoparticles. Herein we propose a novel, previously unexploited method for the biological syntheses of polymorphic gold nanoparticles with potent biological applications.

  19. Green synthesis of gold nanoparticles using Citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) aqueous extract and its characterization.

    Science.gov (United States)

    Sujitha, Mohanan V; Kannan, Soundarapandian

    2013-02-01

    This study reports the biological synthesis of gold nanoparticles by the reduction of HAuCl(4) by using citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) juice extract as the reducing and stabilizing agent. A various shape and size of gold nanoparticles were formed when the ratio of the reactants were altered with respect to 1.0mM chloroauric acid solution. The gold nanoparticles obtained were characterized by UV-visible spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). TEM studies showed the particles to be of various shapes and sizes and particle size ranges from 15 to 80 nm. Selected-area electron diffraction (SAED) pattern confirmed fcc phase and crystallinity of the particles. The X-ray diffraction analysis revealed the distinctive facets (111, 200, 220 and 222 planes) of gold nanoparticles. Dynamic light scattering (DLS) studies revealed that the average size for colloid gp(3) of C. limon, C. reticulata and C. sinensis are 32.2 nm, 43.4 nm and 56.7 nm respectively. The DLS graph showed that the particles size was larger and more polydispersed compared to the one observed by TEM due to the fact that the measured size also includes the bio-organic compounds enveloping the core of the Au NPs. Zeta potential value for gold nanoparticles obtained from colloid gp(3) of C. limon, C. reticulata and C. sinensis are -45.9, -37.9 and -31.4 respectively indicating the stability of the synthesized nanoparticles. Herein we propose a novel, previously unexploited method for the biological syntheses of polymorphic gold nanoparticles with potent biological applications.

  20. Tetraploidy enhances boron-excess tolerance in Carrizo Citrange (Citrus sinensis L. Osb. x Poncirus trifoliata L. Raf.

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    Marta eRuiz

    2016-05-01

    Full Text Available Tetraploidy modifies root anatomy which may lead to differentiated capacity to uptake and transport mineral elements. This work provides insights into physiological and molecular characters involved in boron (B toxicity responses in diploid (2x and tetraploid (4x plants of Carrizo citrange (Citrus sinensis L. Osb. x Poncirus trifoliata L. Raf., a widely used citrus rootstock. With B excess, 2x plants accumulated more B in leaves than 4x plants, which accounted for their higher B uptake and root-to-shoot transport rates. Ploidy did not modify the expression of membrane transporters NIP5 and BOR1 in roots. The cellular allocation of B excess differed between ploidy levels in the soluble fraction, which was lower in 4x leaves, while cell wall-linked B was similar in 2x and 4x genotypes. This correlates with the increased damage and stunted growth recorded in the 2x plants. The 4x roots were found to have fewer root tips, shorter specific root length, longer diameter, thicker exodermis and earlier tissue maturation in root tips, where the Casparian strip was detected at a shorter distance from the root apex than in the 2x roots. The results presented herein suggest that the root anatomical characters of the 4x plants play a key role in their lower B uptake capacity and root-to-shoot transport.

  1. Rootstock assessment for root-knot nematode management in grafted honeydew melon

    Science.gov (United States)

    Root-knot nematodes (RKN) are one of the most damaging soilborne pathogens of honeydew melon (Cucumis melo var. inodorus). Currently their management is dependent on soil fumigation. Vegetable grafting with resistant rootstocks may be an effective approach for RKN management in the sustainable produ...

  2. Detection of drought tolerant genes within seedling apple rootstocks in Syria

    Science.gov (United States)

    This investigation was conducted to detect the drought tolerant genes (four genes) within seedling apple rootstocks derived from five apple genotypes, including Syrian apple cultivars. The results showed that the gene MdPepPro (a cyclophilin) was found in all studied genotypes and their progenies e...

  3. Elevation, rootstock, and soil depth affect the nutritional quality of mandarin oranges

    Science.gov (United States)

    The effects of elevation, rootstock, and soil depth on the nutritional quality of mandarin oranges from 11 groves in California were investigated by nuclear magnetic resonance (NMR) spectroscopy by quantifying 29 compounds and applying multivariate statistical data analysis. A comparison of the juic...

  4. Biosafety considerations of RNAi-mediated virus resistance in fruit-tree cultivars and in rootstock.

    Science.gov (United States)

    Lemgo, Godwin Nana Yaw; Sabbadini, Silvia; Pandolfini, Tiziana; Mezzetti, Bruno

    2013-12-01

    A major application of RNA interference (RNAi) is envisaged for the production of virus-resistant transgenic plants. For fruit trees, this remains the most, if not the only, viable option for the control of plant viral disease outbreaks in cultivated orchards, due to the difficulties associated with the use of traditional and conventional disease-control measures. The use of RNAi might provide an additional benefit for woody crops if silenced rootstock can efficiently transmit the silencing signal to non-transformed scions, as has already been demonstrated in herbaceous plants. This would provide a great opportunity to produce non-transgenic fruit from transgenic rootstock. In this review, we scrutinise some of the concerns that might arise with the use of RNAi for engineering virus-resistant plants, and we speculate that this virus resistance has fewer biosafety concerns. This is mainly because RNAi-eliciting constructs only express small RNA molecules rather than proteins, and because this technology can be applied using plant rootstock that can confer virus resistance to the scion, leaving the scion untransformed. We discuss the main biosafety concerns related to the release of new types of virus-resistant plants and the risk assessment approaches in the application of existing regulatory systems (in particular, those of the European Union, the USA, and Canada) for the evaluation and approval of RNAi-mediated virus-resistant plants, either as transgenic varieties or as plant virus resistance induced by transgenic rootstock.

  5. Formation of ‘Crioula’ guava rootstock under saline water irrigation and nitrogen doses

    Directory of Open Access Journals (Sweden)

    Leandro de P. Souza

    Full Text Available ABSTRACT The objective of this research was to evaluate the growth and formation of fresh and dry weight of ‘Crioula’ guava rootstock irrigated with waters of different saline levels and nitrogen (N doses, in an experiment conducted in plastic tubes under greenhouse conditions. The experimental design was randomized blocks, in a 5 x 4 factorial scheme with four replicates, and the treatments consisted of five levels of water electrical conductivity - ECw (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1 and four N doses (70, 100, 130 and 160% of the N dose recommended for the cultivation of guava seedlings, cv. ‘Paluma’. The dose referring to 100% corresponds to 773 mg of N dm-3. The highest growth of ‘Crioula’ guava rootstock was obtained with ECw of 0.3 dS m-1 and fertilization of 541.1 mg N dm-3 of soil; increasing N doses did not reduce the deleterious effect of the salt stress on the growth and phytomass formation of ‘Crioula’ guava rootstock; irrigation with water of up to 1.75 dS m-1, in the production of guava rootstocks, promotes acceptable reduction of 10% in growth and quality of the seedlings.

  6. Plant resistance within the Rutaceae to Asian citrus psyllid

    Science.gov (United States)

    USDA-ARS recently initiated research on host plant resistance to the Asian citrus psyllid. The psyllid is an important invasive pest of citrus in the United States because it transmits a serious disease of citrus known as huanglongbing (citrus greening). There is no cure for this bacterial disease. ...

  7. 7 CFR 319.56-38 - Citrus from Chile.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Citrus from Chile. 319.56-38 Section 319.56-38... from Chile. Clementines (Citrus reticulata Blanco var. Clementine), mandarins (Citrus reticulata Blanco), and tangerines (Citrus reticulata Blanco) may be imported into the United States from Chile,...

  8. A comparison of plant species for rearing Asian citrus psyllid

    Science.gov (United States)

    Five plant genotypes were compared with respect to Asian citrus psyllid (ACP) reproduction potential: Bergera koenigii, Citrus aurantiifolia, C. macrophylla, C. taiwanica and Murraya paniculata. Asian citrus psyllid reproduction is dependent on young flush and thus Asian citrus psyllid production po...

  9. Joint effects of citrus peel use and black tea intake on the risk of squamous cell carcinoma of the skin

    Directory of Open Access Journals (Sweden)

    Harris Robin B

    2001-08-01

    Full Text Available Abstract Background Differences in tea drinking habits and/or citrus peel use are likely to vary by populations and could contribute to the inconsistencies found between studies comparing their consumption and cancer risk. Methods A population-based case-control study was used to evaluate the relationships between citrus peel use and black tea intake and squamous cell carcinoma (SCC of the skin. Moreover, we assessed the independent and interactive effects of citrus peel and black tea in the development of SCC. Results Hot and iced teas were consumed by 30.7% and 51.8% of the subjects, respectively. Peel consumption was reported by 34.5% of subjects. Controls were more likely than were cases to report citrus peel use (odds ratio (OR = 0.67 and hot tea intake (OR = 0.79. After adjustment for hot and iced tea intake, the ORs associated with citrus peel use were 0.55 and 0.69, respectively, whereas the corresponding adjusted ORs for hot and iced tea intake after adjustment for citrus peel use were 0.87 and 1.22 respectively. Compared with those who did not consume hot black tea or citrus peel, the adjusted ORs associated with sole consumption of hot black tea or citrus peel were 0.60 and 0.30, respectively. Subjects who reported consumption of both hot black tea and citrus peel had a significant marked decrease (OR= 0.22; 95% CI = 0.10 – 0.51 risk of skin SCC. Conclusion These results indicate that both citrus peel use and strong (hot black tea have independent potential protective effects in relation to skin SCC.

  10. Desenvolvimento de um sistema de apoio à decisão para a diagnose de doenças, pragas e distúrbios abióticos dos citros Development of a decision support system for the diagnosis of citrus diseases, pests, and abiotic factors

    Directory of Open Access Journals (Sweden)

    Cleilson do Nascimento Uchôa

    2010-06-01

    Full Text Available A preocupação com a diagnose dos problemas que afetam as plantas cítricas proporcionou ao longo dos anos o acúmulo de conhecimento, que precisava ser organizado e divulgado de forma eficiente e rápida. Dessa forma, objetivou-se com esse trabalho construir uma base de conhecimentos para diagnóstico de doenças bióticas e abióticas dos citros, desenvolver e implementar o sistema de apoio à decisão (SAD e avaliar o sistema. O SAD foi construído utilizando a ferramenta 'Borland Delphi' versão 5. Foram formuladas 562 perguntas, 322 regras e anexadas fotografias para facilitar o diagnóstico de 34 doenças, 40 pragas e 34 distúrbios abióticos dos citros. A avaliação do SAD foi dividida em verificação e validação. Na verificação, o SAD foi submetido a uma análise por meio de questionário a 5 especialistas em citros. A validação do programa foi realizada com quatro grupos, de diferentes níveis de conhecimento (10 pessoas/grupo, tentando diagnosticar corretamente. Obteve-se um acerto de 45,6% dos usuários e 93,6% do SAD. O sistema foi denominado Dr. Citrus (protótipo com registro no INPI n° 014070009188.The concern about the diagnosis of problems affecting citrus led to an accumulation of knowledge over the years. However, such accumulated knowledge needed to be organized and efficiently disseminated. Thus, the aims of this work were to build a knowledge basis for the diagnosis of abiotic and biotic citrus diseases to develop and implement a Decision Support System (DSS and to test and evaluate this system. DSS was built by using the tool 'Borland Delphi' version 5. A total of 562 questions were formulated, including 322 rules, besides photographs to help in the diagnosis of 34 diseases, 40 pests and 34 abiotics disturbances in citrus. DSS evolution was divided into verification and validation. In the verification phase, DSS was analyzed by means of a questionnaire applied to citrus specialists. The program validation phase

  11. Rapid cyling plant breeding in citrus

    Science.gov (United States)

    Resistance or tolerance to huanglongbing (HLB) and other important traits have been identified in several citrus types and relatives and associated markers should be identified soon. What is urgently needed in addition is an accelerated strategy for citrus variety breeding. Identification and use of...

  12. Cryopreservation and Cryotherapy of Citrus Cultivars

    Science.gov (United States)

    Long-term conservation of Citrus clones can be accomplished by cryopreservation. Shoot tips will survive liquid nitrogen exposure and storage when appropriately desiccated and treated with cryoprotectant solutions. In our research, vegetative Citrus budwood is shipped from Riverside to Fort Collin...

  13. Rootstock alleviates PEG-induced water stress in grafted pepper seedlings: physiological responses.

    Science.gov (United States)

    Penella, Consuelo; Nebauer, Sergio G; Bautista, Alberto San; López-Galarza, Salvador; Calatayud, Ángeles

    2014-06-15

    Recent studies have shown that tolerance to abiotic stress, including water stress, is improved by grafting. In a previous work, we took advantage of the natural variability of Capsicum spp. and selected accessions tolerant and sensitive to water stress as rootstocks. The behavior of commercial cultivar 'Verset' seedlings grafted onto the selected rootstocks at two levels of water stress provoked by adding 3.5 and 7% PEG (polyethylene glycol) was examined over 14 days. The objective was to identify the physiological traits responsible for the tolerance provided by the rootstock in order to determine if the tolerance is based on the maintenance of the water relations under water stress or through the activation of protective mechanisms. To achieve this goal, various physiological parameters were measured, including: water relations; proline accumulation; gas exchange; chlorophyll fluorescence; nitrate reductase activity; and antioxidant capacity. Our results indicate that the effect of water stress on the measured parameters depends on the duration and intensity of the stress level, as well as the rootstock used. Under control conditions (0% PEG) all plant combinations showed similar values for all measured parameters. In general terms, PEG provoked a strong decrease in the gas exchange parameters in the cultivar grafted onto the sensitive accessions, as also observed in the ungrafted plants. This effect was related to lower relative water content in the plants, provoked by an inefficient osmotic adjustment that was dependent on reduced proline accumulation. At the end of the experiment, chronic photoinhibition was observed in these plants. However, the plants grafted onto the tolerant rootstocks, despite the reduction in photosynthetic rate, maintained the protective capacity of the photosynthetic machinery mediated by osmotic adjustment (based on higher proline content). In addition, water stress limited uptake and further NO3(-) transfer to the leaves. Increased

  14. Botanicals, selective insecticides, and predators to control Diaphorina citri (Hemiptera: Liviidae) in citrus orchards.

    Science.gov (United States)

    Khan, Azhar A; Afzal, Muhammad; Qureshi, Jawwad A; Khan, Arif M; Raza, Abubakar M

    2014-12-01

    The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama vectors pathogens that cause huanglongbing (HLB) or citrus greening devastating and economically important disease present in most citrus growing regions. Young citrus shoots are required for psyllid reproduction and development. During winter citrus trees produce little or no new growth. Overwintering adults reproduce in spring on newly emerging shoots also attractive to other pests and beneficial insects. Botanicals and relatively selective insecticides could help to conserve beneficial insects and reduce pest resistance to insecticides. Sprays of Azadirachtin (Neem), Tropane (Datura), Spirotetramat, Spinetoram, and broad-spectrum Imidacloprid were evaluated to control ACP in spring and summer on 10-year-old "Kinow" Citrus reticulata Blanco trees producing new growth. Psyllid populations were high averaging 5-9 nymphs or adults per sample before treatment application. Nymphs or adults were significantly reduced to 0.5-1.5 per sample in all treatments for 3 weeks, average 61%-83% reduction. No significant reduction in ladybeetles Adalia bipunctata, Aneglei scardoni, Cheilomenes sexmaculata, and Coccinella septempunctata was observed. Syrphids, spiders and green lacewings were reduced in treated trees except with Tropane. Studies are warranted to assess impact of these predators on ACP and interaction with insecticides. Observed reduction in ACP populations may not be enough considering its reproductive potential and role in the spread of HLB. Follow-up sprays may be required to achieve additional suppression using rotations of different insecticides.

  15. Citrus quarantine, sanitary and certification programs in the USA. Prevention of introduction and distribution of citrus diseases

    Science.gov (United States)

    Citrus germplasm originated in Australasia, the Far East, and Africa, thus all citrus grown in the New World was imported. This importation of citrus also resulted in importation of graft transmissible pathogens of citrus, many of which are latent in their original host but can cause epidemics of t...

  16. Maiden pear trees growth in replant soil after inoculation of rootstocks with mycorrhizal inoculum

    Directory of Open Access Journals (Sweden)

    Sławomir Świerczyński

    2015-03-01

    Full Text Available In the production of fruit trees it is important to set up a nursery always in a new site, alternatively to follow crop rotation rules. It is not always possible due to the size of a farm and production volume. In order to limit the effects of replant soil one can use different procedures before setting up a nursery. Chemical methods, however, must be replaced with non chemical ones due to environmental protection and reduction of production costs. In the experiment conducted in 2009-2012, growth of maiden pear trees of ‘Conference’ growing on three quince MA, MC, S1 rootstocks, cultivated in replant and non-replant soil after the use of mycorrhizal treatment, was compared. The strongest growth of maiden pear trees was obtained on non-replant soil with mycorrhizal and without mycorrhizal treatment of rootstocks. Inoculation of rootstocks influenced positively the height and fresh mass of the root system of maiden pear trees growing on two considered sites. On the other hand, inoculation did not rise the diameter of stem and number of lateral shoots of the maidens. Influence of mycorrhizal treatment of rootstocks on the length of lateral shoots was not obvious. Significantly the best results of maiden pear trees growth, except for the stem diameter, were obtained on MA quince compared to two other types. The mycorrhizal treatment gave better result of percentage obtained by maiden pear trees only in the replant site. The best efficiency of maiden pear trees in nursery production was observed for MA quince rootstock.

  17. Citrus asymmetric somatic hybrids produced via fusion of gamma-irradiated and iodoacetamide-treated protoplasts

    Energy Technology Data Exchange (ETDEWEB)

    Bona, Claudine Maria de [Instituto Agronomico do Parana (IAPAR), Curitiba, PR (Brazil)], e-mail: debona@iapar.br; Gould, Jean Howe [Texas A and M University, College Station, TX (United States). Dept. of Ecosystem Science and Management], e-mail: gould@tamu.edu; Miller Junior, J. Creighton [Texas A and M University, College Station, TX (United States). Dept. of Horticultural Sciences], e-mail: jcmillerjr@tamu.edu; Stelly, David [Texas A and M University, College Station, TX (United States). Dept. of Soil and Crop Sciences], e-mail: stelly@tamu.edu; Louzada, Eliezer Silva [Texas A and M University, Kingsville, TX (United States). Citrus Center], e-mail: e-louzada@tamu.edu

    2009-05-15

    The objective of this study was to produce citrus somatic asymmetric hybrids by fusing gamma.irradiated protoplasts with iodoacetamide-treated protoplasts. Protoplasts were isolated from embryogenic suspension cells of grapefruit (Citrus paradisi Macfad.) cultivars Ruby Red and Flame, sweet oranges (C. sinensis Osbeck) 'Itaborai', 'Natal', Valencia', and 'Succari', from 'Satsuma' (C. unshiu Marcow.) and 'Changsha' mandarin (C. reticulata Blanco) and 'Murcott' tangor (C. reticulata x C. sinensis). Donor protoplasts were exposed to gamma rays and receptor protoplasts were treated with 3 mmol L{sup -1} iodoacetamide (IOA), and then they were fused for asymmetric hybridization. Asymmetric embryos were germinated, and the resulting shoots were either grafted onto sour orange, rough lemon or 'Swingle' (C. paradisi x Poncirus trifoliata) x 'Sunki' mandarin rootstock seedlings, or rooted after dipping their bases in indol.butyric acid (IBA) solution. The products were later acclimatized to greenhouse conditions. Ploidy was analyzed by flow cytometry, and hybridity was confirmed by amplified fragment length polymorphism (AFLP) analysis of plantlet DNA samples. The best treatment was the donor-recipient fusion combination of 80 Gy.irradiated 'Ruby Red' protoplasts with 20 min IOA.treated 'Succari' protoplasts. Tetraploid and aneuploid plants were produced. Rooting recalcitrance was solved by dipping shoots' stems in 3,000 mg L{sup -1} IBA solution for 10 min. (author)

  18. Exploiting BAC-end sequences for the mining, characterization and utility of new short sequences repeat (SSR) markers in Citrus.

    Science.gov (United States)

    Biswas, Manosh Kumar; Chai, Lijun; Mayer, Christoph; Xu, Qiang; Guo, Wenwu; Deng, Xiuxin

    2012-05-01

    The aim of this study was to develop a large set of microsatellite markers based on publicly available BAC-end sequences (BESs), and to evaluate their transferability, discriminating capacity of genotypes and mapping ability in Citrus. A set of 1,281 simple sequence repeat (SSR) markers were developed from the 46,339 Citrus clementina BAC-end sequences (BES), of them 20.67% contained SSR longer than 20 bp, corresponding to roughly one perfect SSR per 2.04 kb. The most abundant motifs were di-nucleotide (16.82%) repeats. Among all repeat motifs (TA/AT)n is the most abundant (8.38%), followed by (AG/CT)n (4.51%). Most of the BES-SSR are located in the non-coding region, but 1.3% of BES-SSRs were found to be associated with transposable element (TE). A total of 400 novel SSR primer pairs were synthesized and their transferability and polymorphism tested on a set of 16 Citrus and Citrus relative's species. Among these 333 (83.25%) were successfully amplified and 260 (65.00%) showed cross-species transferability with Poncirus trifoliata and Fortunella sp. These cross-species transferable markers could be useful for cultivar identification, for genomic study of Citrus, Poncirus and Fortunella sp. Utility of the developed SSR marker was demonstrated by identifying a set of 118 markers each for construction of linkage map of Citrus reticulata and Poncirus trifoliata. Genetic diversity and phylogenetic relationship among 40 Citrus and its related species were conducted with the aid of 25 randomly selected SSR primer pairs and results revealed that citrus genomic SSRs are superior to genic SSR for genetic diversity and germplasm characterization of Citrus spp.

  19. Relationship between Nacl Concentration of the Irrigation Water and the Plants Moisture Content of Four Antiphylloxeric Rootstocks of Grapevine

    Directory of Open Access Journals (Sweden)

    FATBARDHA SHPATI

    2016-10-01

    Full Text Available Study for the relationship between whole plant moisture content and the shoot hardwood cuttings and NaCl concentration of four antiphylloxeric rootstocks of grapevine was conducted during 2014 -2015 at the Experimental Base of the Agricultural University of Tirana. Rooted rootstock’s cuttings were irrigated using normal tap water up to July 20, and, after that, for 45 days, were irrigated using sodium chloride solucion in six different concentrations [control (normal tap water, 2000, 4000, 6000, 8000, and 10000 ppm]. Obtained results showed that with the increase of NaCl concentration, the whole plant moisture content and the hardwood cuttings, was decreased for all rootstocks under study. For the same NaCl concentration, the moisture content of the entire plants and shoot hardwood cuttings were different for different rootstocks. Ranking of rootstocks, according to the plant moisture content, was 1103P (83.2-83.6%, followed by 140Ru (79.5-79.8%, SO4 (79.3-79.5% and Kober 5BB (79.03-79.2%. The moisture content of shoot hardwood cuttings was lower than moisture content of the whole plant. Ranking of the rootstocks, according to the moisture content of hardwood cuttings, was 1103P (58.2-58.4%, 140Ru (59.8-59.9%, Kober 5BB (55.6-55.9% and SO4 (54.9-55%. Ampelographic assessment of the resistance of the rootstocks to chlorides (salt was carried out using OIV Code 402. Rootstock SO4 was more sensitive and less resistant to sodium chloride concentration compare to 1103 P, 140Ru and Kober 5BB. There were significant differences (p ≤ 0.01 in plant moisture content between NaCl treatments and tested rootstocks.

  20. Nutrição e produção da laranjeira "Folha Murcha" em porta-enxertos e plantas de cobertura permanente na entrelinha Nutrition and yield of the 'Folha Murcha' orange in rootstocks and groundcover management systems

    Directory of Open Access Journals (Sweden)

    Jonez Fidalski

    2006-06-01

    Full Text Available O estado nutricional e a produção de citros não são conhecidos para as diferentes combinações copa/porta-enxertos e plantas de coberturas permanente na entrelinha. O estudo foi instalado em um experimento de laranjeira "Folha Murcha" [Citrus sinensis (L. Osb.] com oito anos de idade, conduzido entre 1997 a 2002, no município de Paranavaí, região Noroeste do Paraná. O solo corresponde a um Argissolo Vermelho distr��fico típico textura areia/franco arenoso. O delineamento experimental foi de blocos ao acaso, sendo os tratamentos constituídos por sete porta-enxertos: limoeiro "Cravo", limoeiro "Rugoso da África", limoeiro "Volcameriano", tangerineira "Cleópatra", tangerineira "Sunki", citrangeiro "C-13" e Trifoliata, com três plantas em cada parcela experimental. As repetições foram constituídas por três blocos com a cobertura Paspalum notatum e por um bloco com Arachis pintoi. Foram avaliados os teores dos nutrientes foliares e a produção de frutos da laranjeira "Folha Murcha". O manejo das entrelinhas com a leguminosa elevou os teores de N à faixa excessiva nas folhas do porta-enxerto limoeiro "Cravo", e reduziu a produção de frutos da laranjeira "Folha Murcha" em relação à gramínea. Nas entrelinhas com gramínea, a produção de frutos da laranjeira "Folha Murcha" foi dependente das safras agrícolas e dos teores foliares de Ca, Mg e Zn. A absorção máxima de Ca pelas folhas de laranjeira "Folha Murcha" precede a de Mg e Zn. Nestas condições, os porta-enxertos tangerineira "Cleópatra" e limoeiro "Rugoso da África" apresentaram maior produção de frutos de laranjeira "Folha Murcha".The nutritional status and yield of citrus are not known for different canopy/rootstocks and soil groundcover management systems. The study was set up in a 8-year-old 'Folha Murcha' [Citrus sinensis (L. Osb.] orange experiment, and was carried out from 1997 to 2002 in Paranavai, in the northwest region of the state of Parana

  1. Annotation of the Asian citrus psyllid genome reveals a reduced innate immune system

    Science.gov (United States)

    Citrus production worldwide is currently facing significant losses due to citrus greening disease, also known as huanglongbing. The citrus greening bacteria, Candidatus Liberibacter asiaticus (CLas), is a persistent propagative pathogen transmitted by the Asian citrus psyllid, Diaphorina citri Kuway...

  2. Quince 'CPP': new dwarf rootstock for pear trees on organic and high density planting

    Directory of Open Access Journals (Sweden)

    Renato Vasconcelos Botelho

    2012-06-01

    Full Text Available In Brazil, pear production presents the same incipient situation over the last 15 years, due mostly to low production technology. In this context, this study aimed to evaluate the development, growth and production of the pear tree cultivars Cascatense, Tenra and Hosui grafted on 'CPP' quince rootstock, using 'FT' pear as interstem. This trial was carried out in Guarapuava, State of Paraná, Southern region of Brazil, by five productive cycles. The pear trees were planted in September of 2004, spaced at 1.0 x 4.0 m (2,500 trees ha-1, trained to the modified central leader, on a Four-wire trellis, with drip irrigation and cultivated under organic production system. The following variables were evaluated: sprouting, anthesis, yield, fruit weight, soluble solids content, titratable acidity, pulp firmness, canopy area per plant and per hectare and trunk diameter. The pear tree cv. Tenra was outstanding most of the years for fruit yield, and, consequently, showed the highest accumulated yield over the period (51.6 t ha-1, followed by the cultivars Cascatense (39.7 t ha-1 and Hosui (18.7 t ha-1. All pear cultivars presented suitable physical-chemical characteristics for commercial purposes, with minimal average soluble solids content of 11% at harvest. The maximum canopy area per hectare was attained for cv. Cascatense (3063.2 m², that was considered insufficient for a high yield. These results suggest the needs for studies with higher density planting and other training systems, searching optimize canopy volume. One of the most limiting factors in the organic pear orchard was the incidence of pear dieback caused by Botriosphaeria dothidea, severe more often in pear trees cv. Hosui.

  3. Modification of gibberellin biosynthesis in the grafted apple scion allows control of tree height independent of the rootstock.

    Science.gov (United States)

    Bulley, Sean M; Wilson, Fiona M; Hedden, Peter; Phillips, Andrew L; Croker, Stephen J; James, David J

    2005-03-01

    The availability of short stature apple scions that required minimal applications of chemical growth retardants and could be used with a range of rootstocks would be of considerable benefit to fruit growers. We have suppressed the expression of a gene encoding the gibberellin (GA) biosynthetic enzyme GA 20-oxidase to reduce the levels of bioactive GAs in a scion variety, resulting in significant reductions in stem height. Application of GA3 reversed the effect. The scion remained dwarfed after grafting on to normally invigorating rootstocks, whilst control plants of the same cultivar displayed the expected vigour when grafted on to these rootstocks. This approach could be applicable to any perennial crop variety, allowing dwarf trees to be obtained on any available rootstock or on their own roots without the need for chemical growth retardant application. In effect, seedlings that are well suited to local conditions (drought, salinity) could be employed as tree rootstocks, as could existing rootstocks valued for characters other than vigour control, such as pest and disease resistance.

  4. Preformation in vegetative buds of pistachio (Pistacia vera): relationship to shoot morphology, crown structure and rootstock vigor.

    Science.gov (United States)

    Spann, Timothy M; Beede, Robert H; Dejong, Theodore M

    2007-08-01

    Effects of rootstock, shoot carbohydrate status, crop load and crown position on the number of preformed leaf primordia in the dormant terminal and lateral buds of mature and immature 'Kerman' pistachio (Pistacia vera L.) trees were investigated to determine if rootstock vigor is associated with greater shoot preformation. There was no significant variation in preformation related to the factors studied, suggesting strong genetic control of preformation in 'Kerman' pistachio. The growth differences observed among trees on different rootstocks were associated with greater stimulation of neoformed growth in trees on the more vigorous rootstocks. However, most annual extension growth in mature tree crowns was preformed, contrasting with the relatively high rate of neoformation found in young tree crowns. Large amounts of neoformed growth in young trees may allow the trees to become established quickly and secure resources, whereas predominantly preformed growth in mature trees may allow for continued crown expansion without outgrowing available resources. We hypothesized that the stimulation of neoformed growth by the more vigorous rootstocks is associated with greater resource uptake or transport, or both. Understanding the source of variation in shoot extension growth on different rootstocks has important implications for orchard management practices.

  5. Proteomic study participating the enhancement of growth and salt tolerance of bottle gourd rootstock-grafted watermelon seedlings.

    Science.gov (United States)

    Yang, Yanjuan; Wang, Liping; Tian, Jing; Li, Jing; Sun, Jin; He, Lizhong; Guo, Shirong; Tezuka, Takafumi

    2012-09-01

    An insertion grafting technique to do research on salt tolerance was applied using watermelon (Citrullus lanatus [Thunb.] Mansf. cv. Xiuli) as a scion and bottle gourd (Lagenaria siceraria Standl. cv. Chaofeng Kangshengwang) as a rootstock. Rootstock-grafting significantly relieved the inhibition of growth and photosynthesis induced by salt stress in watermelon plants. Proteomic analysis revealed 40 different expressed proteins in response to rootstock-grafting and/or salt stress. These proteins were involved in Calvin cycle, amino acids biosynthesis, carbohydrate and energy metabolism, ROS defense, hormonal biosynthesis and signal transduction. Most of these proteins were up-regulated by rootstock-grafting and/or susceptible to salt stress. The enhancement of the metabolic activities of Calvin cycle, biosynthesis of amino acids, carotenoids and peroxisomes, glycolytic pathway and tricarboxylic acid cycle will probably contribute to intensify the biomass and photosynthetic capacity in rootstock-grafted seedlings under condition without salt. The accumulation of key enzymes included in these biological processes described above seems to play an important role in the enhancement of salt tolerance of rootstock-grafted seedlings. Furthermore, leucine-rich repeat transmembrane protein kinase and phospholipase may be involved in transmitting the internal and external stimuli induced by grafting and/or salt stress.

  6. Micronutrient Contents of Citrus Orchard Soils in Southern China

    Institute of Scientific and Technical Information of China (English)

    OUYANGTAO

    1993-01-01

    Investigations were carried out on the micronutrient contents,of major citrus orchard soils (involving seven soil great groups in 8 provinces and an autonomous region of southern China),and an evaluation on the abundance and deficiency of available micronutrients in these soils was made in this paper.In southern China,citrus orchard soils derived from sandstone,sandy shale,Quaternary red clay,diluvial deposit,granite gneiss and neritic deposit were deficient in available Mo and B and low in Zn.Those developed on purple sandy shale,limestone and slope deposit were all in short supply of available Zn,B and Mo.Coastal solonchak was fairly abundant in B,but its available Fe,Zn and Mo contents were rather low.

  7. In silico analysis of ESTs from roots of Rangpur lime (Citrus limonia Osbeck under water stress

    Directory of Open Access Journals (Sweden)

    Raquel L. Boscariol-Camargo

    2007-01-01

    Full Text Available CitEST project resulted in the construction of cDNA libraries from different Citrus sp. tissues under various physiological conditions. Among them, plantlets of Rangpur lime were exposed to hydroponic conditions with and without water stress using PEG6000. RNA from roots was obtained and generated a total of 4,130 valid cDNA reads, with 2,020 from the non-stressed condition and 2,110 from the stressed set. Bioinformatic analyses measured the frequency of each read in the libraries and yielded an in silico transcriptional profile for each condition. A total of 40 contigs were differentially expressed and allowed to detect up-regulated homologue sequences to well known genes involved in stress response, such as aquaporins, dehydrin, sucrose synthase, and proline-related synthase. Some sequences could not be classified by using FunCat and remained with an unknown function. A large number of sequences presented high similarities to annotated genes involved with cell energy, protein synthesis and cellular transport, suggesting that Rangpur lime may sustain active cell growth under stressed condition. The presence of membrane transporters and cell signaling components could be an indication of a coordinated morphological adaptation and biochemical response during drought, helping to explain the higher tolerance of this rootstock to water stress.

  8. Imazalil residue loading on citrus fruit as affected by formulation, solution pH and exposure time in aqueous dip treatments

    Science.gov (United States)

    Green mould caused by Penicillium digitatum is responsible for major postharvest fruit losses on the South African fresh citrus export market. Some of these losses, as well as fungicide resistance development, can be attributed to sub-optimal imazalil (IMZ) residue loading on citrus fruit, i.e. <2 µ...

  9. A “walker” tool to place Diaphorina citri (Hemiptera: Liviidae) adults at predetermined sites for bioassays of behavior in citrus (Sapindales: Rutacease) trees

    Science.gov (United States)

    A walker tool was developed to assist placement of D. citri on citrus host trees in behavioral bioassays. The walker performs better than a commonly used paintbrush tool in the proportion of successful placements and in the reduction of jumps away from the citrus leaf, although it takes about two mi...

  10. Cloning and expressing a highly functional and substrate specific farnesoic acid o-methyltransferase from the Asian citrus psyllid (Diaphorina citri Kuwayama)

    Science.gov (United States)

    The Asian citrus psyllid, Diaphorina citri, transmits a phloem-limited bacterium, Candidatus Liberibacter asiaticus that causes citrus greening disease. Because juvenile hormone (JH) plays an important role in adult and nymphal development, we studied the final steps in juvenile hormone biosynthesis...

  11. HYDRAULICS, CITRUS COUNTY, FL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Recent developments in digital terrain and geospatial database management technology make it possible to protect this investment for existing and future projects to...

  12. Genome editing of the disease susceptibility gene CsLOB1 in citrus confers resistance to citrus canker.

    Science.gov (United States)

    Jia, Hongge; Zhang, Yunzeng; Orbović, Vladimir; Xu, Jin; White, Frank F; Jones, Jeffrey B; Wang, Nian

    2016-12-09

    Citrus is a highly valued tree crop worldwide, while, at the same time, citrus production faces many biotic challenges, including bacterial canker and Huanglongbing (HLB). Breeding for disease-resistant varieties is the most efficient and sustainable approach to control plant diseases. Traditional breeding of citrus varieties is challenging due to multiple limitations, including polyploidy, polyembryony, extended juvenility and long crossing cycles. Targeted genome editing technology has the potential to shorten varietal development for some traits, including disease resistance. Here, we used CRISPR/Cas9/sgRNA technology to modify the canker susceptibility gene CsLOB1 in Duncan grapefruit. Six independent lines, DLOB 2, DLOB 3, DLOB 9, DLOB 10, DLOB 11 and DLOB 12, were generated. Targeted next-generation sequencing of the six lines showed the mutation rate was 31.58%, 23.80%, 89.36%, 88.79%, 46.91% and 51.12% for DLOB 2, DLOB 3, DLOB 9, DLOB 10, DLOB 11 and DLOB 12, respectively, of the cells in each line. DLOB 2 and DLOB 3 showed canker symptoms similar to wild-type grapefruit, when inoculated with the pathogen Xanthomonas citri subsp. citri (Xcc). No canker symptoms were observed on DLOB 9, DLOB 10, DLOB 11 and DLOB 12 at 4 days postinoculation (DPI) with Xcc. Pustules caused by Xcc were observed on DLOB 9, DLOB 10, DLOB 11 and DLOB 12 in later stages, which were much reduced compared to that on wild-type grapefruit. The pustules on DLOB 9 and DLOB 10 did not develop into typical canker symptoms. No side effects and off-target mutations were detected in the mutated plants. This study indicates that genome editing using CRISPR technology will provide a promising pathway to generate disease-resistant citrus varieties.

  13. Antifungal Edible Coatings for Fresh Citrus Fruit: A Review

    Directory of Open Access Journals (Sweden)

    Lluís Palou

    2015-12-01

    Full Text Available According to their origin, major postharvest losses of citrus fruit are caused by weight loss, fungal diseases, physiological disorders, and quarantine pests. Cold storage and postharvest treatments with conventional chemical fungicides, synthetic waxes, or combinations of them are commonly used to minimize postharvest losses. However, the repeated application of these treatments has led to important problems such as health and environmental issues associated with fungicide residues or waxes containing ammoniacal compounds, or the proliferation of resistant pathogenic fungal strains. There is, therefore, an increasing need to find non-polluting alternatives to be used as part of integrated disease management (IDM programs for preservation of fresh citrus fruit. Among them, the development of novel natural edible films and coatings with antimicrobial properties is a technological challenge for the industry and a very active research field worldwide. Chitosan and other edible coatings formulated by adding antifungal agents to composite emulsions based on polysaccharides or proteins and lipids are reviewed in this article. The most important antifungal ingredients are selected for their ability to control major citrus postharvest diseases like green and blue molds, caused by Penicillium digitatum and Penicillium italicum, respectively, and include low-toxicity or natural chemicals such as food additives, generally recognized as safe (GRAS compounds, plant extracts, or essential oils, and biological control agents such as some antagonistic strains of yeasts or bacteria.

  14. 2004 SWFWMD Citrus County Lidar Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This metadata record describes the ortho & LIDAR mapping of Citrus County, FL. The mapping consists of LIDAR data collection, contour generation, and production...

  15. Vigor, produtividade e qualidade de frutos de quatro tangerineiras e híbridos sobre quatro porta-enxertos Vegetative growth, yield and fruit quality of four mandarin and hybrid cultivars on four rootstocks

    Directory of Open Access Journals (Sweden)

    Eduardo Sanches Stuchi

    2008-09-01

    Full Text Available Avaliaram-se o desenvolvimento vegetativo, a produção e a qualidade de frutos das cultivares-copa 'Swatow' (Citrus reticulata Blanco, 'Ellendale' [C. reticulata x C. sinensis (L. Osbeck], 'Fortune' (C. clementina hort. ex Tanaka x C. tangerina hort. ex Tanaka e 'Nova' [C. clementina x (C. paradisi Macfad. x C. reticulata] sobre limoeiro 'Cravo' (C. limonia Osbeck, citrumeleiro 'Swingle' (C. paradisi x P. trifoliata (L. Raf., tangelereiro 'Orlando' (C. reticulata x C. paradisi e tangerineira 'Cleópatra' (C. reshni hort. ex Tanaka, de 2000 a 2006. O experimento foi instalado em Bebedouro-SP, em outubro de 1997. As variáveis analisadas foram: produção anual e produção acumulada de todas as cultivares para todos os anos (2000 a 2006, qualidade de frutos em 2005 e 2006 (massa, sólidos solúveis totais, acidez total, ratio, volume da copa, diâmetro do tronco da copa, eficiência de produção (Kg frutos/m³ copa e índice de alternância de produção. A produção acumulada e a qualidade de frutos das cultivares testadas não foram influenciadas pelos porta-enxertos. O citrumelo 'Swingle' induziu menor porte às plantas das cultivares-copa. O tangelo 'Nova' apresentou características adequadas à comercialização in natura. A tangerineira 'Swatow' produziu frutos de qualidade semelhante aos de tangerineira 'Ponkan'. O tangor 'Ellendale' e a tangerineira 'Fortune' apresentaram produção de frutos baixa e irregular.Plant growth, yield, and fruit quality of 'Swatow' (Citrus reticulata Blanco, 'Ellendale' (C. reticulata x Citrus sinensis L. Osbeck, 'Fortune' (Citrus clementina Hort. ex Tan. x Citrus tangerina Hort. ex Tan. e 'Nova' [(C. clementina x (Citrus paradisi Macf. x C. reticulata] mandarins budded on 'Rangpur' lime (C. limonia Osbeck, 'Swingle' citrumelo (P. trifoliata Raf. x C. paradisi Macf., 'Orlando' tangelo (C. reticulata Blanco x C. paradisi Macf., and 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan. were evaluated, from 2000

  16. Transcriptional Characterization of a Widely-Used Grapevine Rootstock Genotype under Different Iron-Limited Conditions

    Science.gov (United States)

    Vannozzi, Alessandro; Donnini, Silvia; Vigani, Gianpiero; Corso, Massimiliano; Valle, Giorgio; Vitulo, Nicola; Bonghi, Claudio; Zocchi, Graziano; Lucchin, Margherita

    2017-01-01

    Iron chlorosis is a serious deficiency that affects orchards and vineyards reducing quality and yield production. Chlorotic plants show abnormal photosynthesis and yellowing shoots. In grapevine iron uptake and homeostasis are most likely controlled by a mechanism known as “Strategy I,” characteristic of non-graminaceous plants and based on a system of soil acidification, iron reduction and transporter-mediated uptake. Nowadays, grafting of varieties of economic interest on tolerant rootstocks is widely used practice against many biotic and abiotic stresses. Nevertheless, many interspecific rootstocks, and in particular those obtained by crossing exclusively non-vinifera genotypes, can show limited nutrient uptake and transport, in particular for what concerns iron. In the present study, 101.14, a commonly used rootstock characterized by susceptibility to iron chlorosis was subjected to both Fe-absence and Fe-limiting conditions. Grapevine plantlets were grown in control, Fe-deprived, and bicarbonate-supplemented hydroponic solutions. Whole transcriptome analyses, via mRNA-Seq, were performed on root apices of stressed and unstressed plants. Analysis of differentially expressed genes (DEGs) confirmed that Strategy I is the mechanism responsible for iron uptake in grapevine, since many orthologs genes to the Arabidopsis “ferrome” were differentially regulated in stressed plant. Molecular differences in the plant responses to Fe absence and presence of bicarbonate were also identified indicating the two treatments are able to induce response-mechanisms only partially overlapping. Finally, we measured the expression of a subset of genes differentially expressed in 101.14 (such as IRT1, FERRITIN1, bHLH38/39) or known to be fundamental in the “strategy I” mechanism (AHA2 and FRO2) also in a tolerant rootstock (M1) finding important differences which could be responsible for the different degrees of tolerance observed. PMID:28105035

  17. Antihyperlipidemic effects of Citrus sinensis, Citrus paradisi, and their combinations

    Directory of Open Access Journals (Sweden)

    Neelam Mallick

    2016-01-01

    Full Text Available Objective: Hyperlipidemia, extensively contributes in the progression of coronary heart diseases and atherosclerosis, but may be managed through alterations in the nutritional pattern. Several studies show that diet rich in polyphenols and antioxidants have antiatherogenic effects. Citrus sinensis and Citrus paradisi are widely known for health benefits and have found to produce antioxidant, anti-inflammatory, and hypolipidemic effects, hence current research was planned to determine the hypolipidemic effects of C. sinensis and C. paradisi in rats receiving diet rich in cholesterol. Materials and Methods: All rats were divided into 11 groups each comprising 10 animals: Normal control group and hyperlipidemic control. C. sinensis treated three groups, C. paradisi treated three groups, C. sinensis and C. paradisi combination treated two groups, and group treated atorvastatin. All rats in the respective groups were treated orally with sterile water, juices, and standard drug for 8 weeks and lipid profile was estimated at the end of dosing. Results: Cholesterol, triglycerides (TGs, and low-density lipoprotein (LDL were decreased at all the three doses of C. sinensis and C. paradisi but rise in high-density lipoprotein (HDL was only significant at 8 ml/kg, and 0.3 ml/kg, respectively. Animals received the combination doses of C. sinensis and C. paradisi also showed a highly significant fall in cholesterol, LDL, and TGs, however HDL level was significantly elevated by SPJ-2 combination. Conclusion: Results suggest that C. sinensis and C. paradisi possess antihyperlipidemic activity due to phytochemicals and other essential nutrients, hence may serve as cardioprotective by preventing thrombosis.

  18. Dwarifng apple rootstock responses to elevated temperatures:A study on plant physiological features and transcription level of related genes

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bei-bei; SUN Jian; LIU Song-zhong; JIN Wan-mei; ZHANG Qiang; WEI Qin-ping

    2016-01-01

    The aim of this study was to investigate the impact of heat stress on physiological features, together with endogenous hormones and the transcription level of related genes, to estimate the heat resistance ability and stress injury mechanism of different dwarifng apple rootstocks. Among the six rootstocks, the rootstocks of native Shao series (SH series) showed better heat stress resistance than those of Budagovski 9 (B9), Cornel-Geneva 24 (CG24), and Maling 26 (M26) from abroad. Among SH series rootstocks, SH1 and SH6 showed higher heat stress resistance than SH40. M26 demonstrated the lowest adaption ability to heat stress, showing higher leaf conductivity and lower liquid water content (LWC) with the increase in temperature. Heat stress also resulted in the suppression of photosynthesis, which showed no signiifcant res-toration after 7-day recovery. It should be noted that although a higher temperature led to a lower LWC and photosynthetic efifciency (Pn) of CG24, there was no signiifcant increase in leaf conductivity, and 7 days after the treatment, thePn of CG24 recovered. The extremely high temperature tolerance of SH series rootstocks could be related to the greater osmotic ad-justment (OA), which was relfected by smaler reductions in leaf relative water content (RWC) and higher turgor potentials and leaf gas exchange compared with the other rootstocks. Determination of hormones indicated multivariate regulation, and it is presumed that a relatively stable expression levels of functional genes under high-temperature stress is necessary for heat stress resistance of rootstocks.

  19. The effects of different salt concentrations on growth and chlorophyll content of some pumpkin rootstocks

    Directory of Open Access Journals (Sweden)

    Köksal AYDİNŞAKİR

    2015-12-01

    Full Text Available This study was conducted to determine the effects of different salinity levels, (0.7, 4.0, 8.0, 12.0, 16.0 dS m-1 on some physiological parameters of Obez F1, Ferro F1, RS841 F1, which are used as rootstocks in watermelon cultivation. Salty irrigation water was obtained through mixing of NaCl and CaCl2 salt into tap water. When the plants were at the 3-4 leaf stage, different salinity levels were applied. Plants were harvested during the phase of florescence. The study was carried out using split plots in randomized complete block design while rootstocks are main plot, salinity levels are sub-plot with three replications. While the salinity level was increasing, the physiological parameters decreased in each three rootstocks. While the plant height changed between 14.4-107.1 cm, the plant leaf area varied between 152.0-2182.7 cm2. Chlorophyll-a, chlorophyll-b and total carotenoid values decreased as the salinity level increased. Excluding the maximum value obtained from control plot, the highest chlorophyll-a, chlorophyll-b, and total carotenoid values were obtained in Obez variety under 4.0 dS m-1 application with 14.8 mg l-1, 12.8 mg l-1 and 0.28 mg g-1 fw, respectively.

  20. Chemical characteristics of grape juices from different cultivar and rootstock combinations

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Mirela Resende Nassur

    2014-07-01

    Full Text Available The objective of this work was to evaluate the influence of different combinations of grape cultivars and rootstocks on chemical characteristics of grape juices. Six treatments were evaluated, consisting of combinations between the Isabel Precoce and BRS Cora grape cultivars and the 'IAC 766', 'IAC 313', and 'IAC 572' rootstocks. Approximately 10 L of juice were obtained per treatment. Analyses of color, total soluble solids content, pH, anthocyanins, total phenolics, total sugars, and quantification and identification of biogenic amines by HPLC were performed. Biogenic amines, such as putrescine, cadaverine, spermidine, and spermine, were found in all evaluated cultivars. By principal component analysis (PCA, treatments can be divided into two groups, according to the cultivar. Juices obtained from 'Isabel Precoce' are characterized by higher levels of total sugar content and soluble solids; however, juices from 'BRS Cora' are positively correlated with phenolic content, anthocyanins, and color and acidity parameters. The differences found by PCA for juices from the Isabel Precoce and BRS Cora cultivars indicate that, regardless of the rootstock used, the most important factor in the chemical characterization of juices is the grape cultivar.

  1. Delivery of Nucleic Acids and Proteins from Grafted Rootstocks for Pathogen and Pest Control

    Directory of Open Access Journals (Sweden)

    Victor eHaroldsen

    2012-03-01

    Full Text Available Grafting has been used in agriculture for over two thousand years. With modern advances in biotechnology, new options for utilizing this proven horticultural technique are emerging. Specifically, trans-grafting, the combination of a genetically engineered (GE rootstock with a wild-type (WT scion, has the potential to provide biotic and abiotic stress tolerance or to increase plant vigor and productivity. Yet, it is unclear whether nucleic acids and proteins will be transmitted across a graft and, if so, whether this movement may affect the efficacy of the trans-grafting approach and/or regulatory oversight of the WT scion and its products. There are reports of the movement of organellar DNA and cellular mRNAs and proteins across graft unions, but to what extent these molecules affect performance of the scion is not clear. Strategies that can be used to limit or enhance nucleic acid or protein movement in order to maximize trans-grafting benefits have not been defined. This paper reviews, using specific examples, the transport of nucleic acids and proteins between rootstock and scion with the objectives of increasing the benefits grafting, particularly for pathogen resistance and defining how use of GE rootstocks effectively extends the horticultural utility of grafting.

  2. Analysis of Transcriptome Differences between Resistant and Susceptible Strains of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae)

    OpenAIRE

    Bin Liu; Gaofei Jiang; Yunfei Zhang; Junli Li; Xiaojiao Li; Jiansu Yue; Fei Chen; Haoqiang Liu; Hongjun Li; Shiping Zhu; Jinjun Wang; Chun Ran

    2011-01-01

    BACKGROUND: The citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains. RESULTS: We obtained 34,159, 30,466 and 32,217 unigenes by assembling the SS reads, RS reads and SS&RS...

  3. Apparent tolerance to huanglongbing in citrus and citrus-related germplasm

    Science.gov (United States)

    In a Ft. Pierce, Florida field planting, growth and huanglongbing (HLB) severity were assessed as indicators of HLB-tolerance on progenies of 83 seed-source accessions of citrus and citrus-relatives from the Riverside, California genebank. The HLB-pathogen (Candidatus Liberibacter asiaticus) and vec...

  4. Interrelations between citrus rust mite, Hirsutella thompsonii and greasy spot on citrus in Surinam

    NARCIS (Netherlands)

    Brussel, van E.W.

    1975-01-01

    Counts of citrus rust mite (Phyllocoptruta oleivora (Ashm.)) on leaves and fruit of citrus rose to a peak in the two dry seasons, the build up taking 4-5 weeks. It then decreased partly through infection by the entomogenous fungus Hirsutellathompsonii Fisher and partly through a decline in feed qual

  5. 78 FR 41259 - Importation of Fresh Citrus Fruit From Uruguay, Including Citrus

    Science.gov (United States)

    2013-07-10

    ... that this argument is invalid due to the year-round marketing of citrus harvested domestically. We made... variety. Total citrus production in Uruguay in 2011 was 270,367 metric tons, which is less than 3 percent... metric tons, respectively, which is less than 3.2 percent of U.S. production and 1 percent of total...

  6. Phyllosticta citriasiana sp. nov., the cause of Citrus tan spot of Citrus maxima in Asia

    NARCIS (Netherlands)

    Wulandari, N.F.; To-anun, C.; Hyde, K.D.; Duong, L.M.; Gruyter, de J.; Meffert, J.P.; Groenewald, J.Z.; Crous, P.W.

    2009-01-01

    Guignardia citricarpa, the causal agent of Citrus Black Spot, is subject to phytosanitary legislation in the European Union and the U.S.A. This species is frequently confused with G. mangiferae, which is a non-pathogenic, and is commonly isolated as an endophyte from citrus fruits and a wide range o

  7. Phyllosticta citriasiana sp nov., the cause of Citrus tan spot of Citrus maxima in Asia

    NARCIS (Netherlands)

    Wulandari, N.F.; To-anun, C.; Hyde, K.D.; Duong, L.M.; de Gruyter, J.; Meffert, J.P.; Groenewald, J.Z.; Crous, P.W.

    2009-01-01

    Guignardia citricarpa, the causal agent of Citrus Black Spot, is subject to phytosanitary legislation in the European Union and the U.S.A. This species is frequently confused with G. mangiferae, which is a non-pathogenic, and is commonly isolated as an endophyte from citrus fruits and a wide range o

  8. Detection of non-typhoid Salmonella infection by citrus and citrus extracts in Lao PDR

    Institute of Scientific and Technical Information of China (English)

    Yutaka Midorikawa; Satoshi Nakamura; Rattanaphone Phetsouvanh; Manivanh Vongsouvaht; Kaoru Midorikawa

    2010-01-01

    Objective: To know the current state of non-typhoid Salmonella infection in Laos. To examine the usefulness of new screening methods for Salmonella using citrus. Methods: Non-typhoidSalmonella infection of person in Lao PDR was studied in this research (2004-2009). The site was Vientiane capital city in 2004. Research from rural villages locating suburb of Vientiane during 2005-2008 was carried out. Rural villages in Attapu province where ethnic minorities were living was searched for this study in 2009. During this research, to detect Salmonella strain, a new method using citrus and citrus extract named MY phenomenon that observing black ring (MIDO ring) on DHL agar was tried. The slice lemon and lime were used for this trial in 2004. After 2005, disk of ascorbic acid and citric acid were used for the device instead of citrus fruits itself. Results: During this research, 65 of 272 human samples (23.9%) were infected with non-typhoid Salmonella. Conclusions: During this study, the method using citrus and citrus extracts was accepted for the detection of Salmonella. This study shows that with citrus and citrus extract, detection of Salmonella is possible using only DHL media. Results suggest that infectious rate of non-typhoid Salmonella was high.

  9. Postharvest decay control of citrus fruit by preharvest pyrimethanil spray.

    Science.gov (United States)

    D'Aquino, S; Angioni, A; Suming, D; Palma, A; Schirra, M

    2013-01-01

    Preharvest infections or conidia load on fruit surface by Penicillium digitatum, P. italicum, Alternaria citri and other filamentous fungi can cause important postharvest losses of citrus fruit. Reduction in pruning frequency occurred in the last decade together with un-picked yield that eventually rots on the trees have increased the risk of postharvest decay especially when environmental conditions at picking time are favourable to pathogens' development. Sanitation procedures in the packinghouses, alternate use of postharvest fungicides with different modes of action, along with fungicide application before harvest could be an effective approach to minimize postharvest decay in citrus fruit. The present study investigated the effectiveness of a preharvest treatment with pyrimethanil (PYR), a broad spectrum fungicide, recently registered in different citrus-producing countries for postharvest treatments of citrus fruit and widely used worldwide as a preharvest treatment to control various diseases in different crops. PYR (750 mg/L) was sprayed by a hand-back sprayer at run-off on 'Fremont' mandarins. The day after the treatment, half of the trees were sprayed with a 10(4) conidial suspension of P. digitatum at run-off. Fruit were harvested following 2 or 4 weeks from treatments. Sound or either wounded 2-mm-deep and 2-mm-wide or superficial wound-scratched fruit were stored at 20 degrees C and 90% RH and inspected for decay after 1, 2 or 3 weeks of storage. In fruit harvested after 2 weeks from field treatment, PYR remarkably reduced decay development during two weeks of storage in sound fruit and in wound-scratched fruit and was fairly effective even after 4 weeks from treatment, but was ineffective in fruit wounded 2 mm deep and 2 mm wide. PYR was also effective in reducing preharvest decay incited by P. digitatum, P. italicum and Botrytis cinerea, but not by other pathogens. Results show that preharvest treatment with PYR could be a feasible approach to reduce

  10. Genome-wide analysis of citrus R2R3MYB genes and their spatiotemporal expression under stresses and hormone treatments.

    Directory of Open Access Journals (Sweden)

    Rangjin Xie

    Full Text Available The R2R3MYB proteins represent one of the largest families of transcription factors, which play important roles in plant growth and development. Although genome-wide analysis of this family has been conducted in many species, little is known about R2R3MYB genes in citrus, In this study, 101 R2R3MYB genes has been identified in the citrus (Citrus sinesis and Citrus clementina genomes, which are almost equal to the number of rice. Phylogenetic analysis revealed that they could be subdivided into 21 subgroups. The evolutionary relationships and the intro-exon organizations were also analyzed, revealing strong gene conservation but also the expansions of particular functional genes during the plant evolution. Tissue-specific expression profiles showed that 95 citrus R2R3MYB genes were expressed in at least one tissue and the other 6 genes showed very low expression in all tissues tested, suggesting that citrus R2R3MYB genes play important roles in the development of all citrus organs. The transcript abundance level analysis during abiotic conditions (NaCl, abscisic acid, jasmonic acid, drought and low temperature identified a group of R2R3MYB genes that responded to one or multiple treatments, which showed a promising for improving citrus adaptation to stresses. Our results provided an essential foundation for the future selection of the citrus R2R3MYB genes for cloning and functional dissection with an aim of uncovering their roles in citrus growth and development.

  11. Genome-wide analysis of citrus R2R3MYB genes and their spatiotemporal expression under stresses and hormone treatments.

    Science.gov (United States)

    Xie, Rangjin; Li, Yongjie; He, Shaolan; Zheng, Yongqiang; Yi, Shilai; Lv, Qiang; Deng, Lie

    2014-01-01

    The R2R3MYB proteins represent one of the largest families of transcription factors, which play important roles in plant growth and development. Although genome-wide analysis of this family has been conducted in many species, little is known about R2R3MYB genes in citrus, In this study, 101 R2R3MYB genes has been identified in the citrus (Citrus sinesis and Citrus clementina) genomes, which are almost equal to the number of rice. Phylogenetic analysis revealed that they could be subdivided into 21 subgroups. The evolutionary relationships and the intro-exon organizations were also analyzed, revealing strong gene conservation but also the expansions of particular functional genes during the plant evolution. Tissue-specific expression profiles showed that 95 citrus R2R3MYB genes were expressed in at least one tissue and the other 6 genes showed very low expression in all tissues tested, suggesting that citrus R2R3MYB genes play important roles in the development of all citrus organs. The transcript abundance level analysis during abiotic conditions (NaCl, abscisic acid, jasmonic acid, drought and low temperature) identified a group of R2R3MYB genes that responded to one or multiple treatments, which showed a promising for improving citrus adaptation to stresses. Our results provided an essential foundation for the future selection of the citrus R2R3MYB genes for cloning and functional dissection with an aim of uncovering their roles in citrus growth and development.

  12. EFEITO DO ARMAZENAMENTO DE HASTES DE LARANJA CACAU (Citrus sinensis Osb NO "PEGAMENTO" DE BORBULHAS EFFECT OF THE STORAGE PERIOD OF “CACAU” ORANGE (Citrus sinensis OSB BUDWOODS ON THE QUALITY OF BUDS FOR GRAFTING

    Directory of Open Access Journals (Sweden)

    Maria Terezinha Teixeira Lopes

    2007-09-01

    Full Text Available

    O presente trabalho foi realizado na Escola de Agronomia e Veterinária da UFGO, com o objetivo de estudar o efeito da conservação de borbulhas de laranja “Cacau” (Citrus sinensis Osb embaladas em sacos plásticos, no pegamento de enxertos. Os tratamentos utilizados foram enxertia com borbulhas de hastes com 0, 5, 10, 15 e 20 dias de conservação. A percentagem de enxertos brotados decresceu linearmente em função do período de conservação. À medida que aumentava a intensidade de descoloração das hastes, diminuía a percentagem de "pegamento" de enxertos. Para nossas condições as borbulhas de laranja "cacau" (Citrus sinensis Osb não devem ser conservadas em sacos plásticos, à temperatura ambiente, por mais de 5 dias, pois a percentagem de enxertos brotados decresceu linearmente com o período de conservação das hastes.

    This work was carried out at the Escola de Agronomia e Veterinária da UFGO. This study was made to test the effect of the storage period of the “cacau” orange budwood on the quality of buds for grafting. Budwoods of the “Cacau” orange (Citrus sinensis  Osb were harvested, packed in polyethylene bags and maintained at environmental temperature. The buds were grafted on rootstocks of Rangpur lime (Citrus limonia, Osb at intervals of 6 days (0, 5, 10, 15 and 20 days. It was noted that the loss of bud viability increased simultaneously with progressive change in budwood color from the natural green to an intense brown. The percentages of buds alive after 60 days of grafting were: 100% on the day budwoods were harvested; 70% after 5 days of storage; 36% after 10 days of storage and 00% after 15 days.

  13. The effect of different types of rootstock on the quality of maiden trees of sweet cherry (Prunus avium L. cv. ‘Regina’

    Directory of Open Access Journals (Sweden)

    Piotr Baryła

    2014-12-01

    Full Text Available Over the period 2006–2009 in Lublin, a study was conducted to determine the effect of five types of rootstock: ‘Colt’, ‘F12/1’, sweet cherry (Prunus avium L., ‘GiSelA 5’ and ‘Piast’ mahaleb cherry (Prunus mahaleb L., on the growth and quality of maiden sweet cherry trees cv. ‘Regina’ in a commercial nursery. Based on the three-year average, rootstocks were shown to have a significant effect on the investigated quality characteristics of maiden sweet cherry trees. Trees budded on ‘Colt’ vegetative rootstock were characterized by strongest growth and best quality. In each year, they were thicker, higher and better branched than sweet cherries on the rootstock. Under the tested conditions, ‘GiSelA 5’ dwarf rootstock significantly reduced the growth and quality of budded sweet cherry trees in the nursery. During the period 2007–2009, no physiological incompatibility symptoms were observed ‘Regina’ sweet cherry cv. and ‘Piast’ seedling rootstocks. The growth of trees budded on ‘Piast’ mahaleb cherry was poorer than on ‘Colt’ clonal rootstock, but it was stronger than on ‘F12/1’ and Prunus avium L. rootstocks.

  14. The Effect of Water Stress on Some Morphological, Physiological, and Biochemical Characteristics and Bud Success on Apple and Quince Rootstocks

    Directory of Open Access Journals (Sweden)

    Ibrahim Bolat

    2014-01-01

    Full Text Available The effects of different water stress (control, medium, and severe on some morphological, physiological, and biochemical characteristics and bud success of M9 apple and MA quince rootstocks were determined. The results showed that water stress significantly affected most morphological, physiological, and biochemical characteristics as well as budding success on the both rootstocks. The increasing water stress decreased the relative shoot length, diameter, and plant total fresh and dry weights. Leaf relative water content and chlorophyll index decreased while electrolyte leakage increased with the increase of water stress in both rootstocks. An increase in water stress also resulted in reduction in budding success in Vista Bella/M9 (79.33% and 46.67% and Santa Maria/MA (70.33% and 15.33% combinations. However, the water stress in Santa Maria/MA was more prominent. The increase in water stress resulted in higher peroxidase activities as well as phenol contents in both rootstocks. Although catalase activity, anthocyanin, and proline contents increased with the impact of stress, this was not statistically significant. The results suggest that the impact of stress increased with the increase of water stress; therefore, growers should be careful when using M9 and MA rootstocks in both nursery and orchards where water scarcity is present.

  15. Agronomical Parameters, Sugar Profile and Antioxidant Compounds of “Catherine” Peach Cultivar Influenced by Different Plum Rootstocks

    Directory of Open Access Journals (Sweden)

    Carolina Font i Forcada

    2014-02-01

    Full Text Available The influence of seven plum rootstocks (Adesoto, Monpol, Montizo, Puebla de Soto 67 AD, PM 105 AD, St. Julien GF 655/2 and Constantí 1 on individual and total sugars, as well as on antioxidant content in fruit flesh of “Catherine” peaches, was evaluated for three years. Agronomical and basic fruit quality parameters were also determined. At twelve years after budding, significant differences were found between rootstocks for the different agronomic and fruit quality traits evaluated. The Pollizo plum rootstocks Adesoto and PM 105 AD seem to induce higher sweetness to peach fruits, based on soluble solids content, individual (sucrose, fructose and sorbitol and total sugars. A clear tendency was also observed with the rootstock Adesoto, inducing the highest content of phenolics, flavonoids, vitamin C and relative antioxidant capacity (RAC. Thus, the results of this study demonstrate the significant effect of rootstock on the sugar profile and phytochemical characteristics of peach fruits. In addition, this work shows the importance of the sugar profile, because specific sugars play an important role in peach flavour quality, as well as the studied phytochemical compounds when looking for high quality peaches with enhanced health properties.

  16. Evaluation of PAL activity, Phenolic and Flavonoid Contents in Three Pistachio (Pistacia vera L. Cultivars Grafted onto Three Different Rootstocks

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    N. Nadernejad

    2013-08-01

    Full Text Available Phenylalanine ammonia lyase (PAL is a biochemical marker of the environmental stress and plays a pivotal role in phenolic synthesis. The lower ROS level and oxidative damage was observed in grafted plants and the rootstocks have a profound influence on the biochemical composition, especially phenolic compounds. Regarding the importance of the effect rootstocks have on scion in pistachio trees, this study was carried out to assess and compare three pistachio cultivars ("Ahmadaghaii", "Ohadi" and "Kallehghuchi" on three rootstocks (Mutica, Ahli, Sarakhs. PAL activity, phenolic compounds, flavonoid and anthocyanin contents in leaves, flowers and fruits were measured toward the selection of the most suitable and compatible rootstock/scion resistant to environmental stresses. The results showed that PAL activity was different among the cultivars and organs. A positive correlation was observed between PAL activity and phenolic compounds in the leaves and flowers of Mutica- Ahmadaghaii, suggesting that it is more resistant than the others to environmental stresses. PAL activity and total phenolics in fruits of pistachio suffered a decrease when the maturation processes began. The hulls of the pistachio fruits contained high levels of phenolic compounds especially in Mutica-Ahmadaghaii suggesting its function as a protective layer and a defense chemical against ultraviolet radiation and pathogen. Our results indicated the presence of a number of bioactive compounds in kernels with the highest amount belonging to Mutica- Ahmadaghaii, and therefore it is concluded that pistachio rootstocks may affect the antioxidant compounds in kernels.

  17. The effect of rootstocks on the growth and yielding of sour cherry cv. 'Łutówka'

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    Stanisław Wociór

    2012-12-01

    Full Text Available The strength of growth of 'Łutówka' trees was related to the soil quality and the rootstock. Measurements of the tree trunks and the crown size showed that on fertile soil the trees grafted on Mahaleb cherry grew worse, forming by 12% thinner trunks and by over 20% (significantly smaller crowns as compared to Mazzard cherry trees. On poor sandy-loamy soil the crowns of trees grafted on Mahaleb were significantly, more than 40% bigger than those on Mazzard cherry. No significant differences in the yielding and productivity of trees grafted on Mahaleb and Mazzard cherry trees were found on grey brown podzolic soil. The experiment conducted on sandy-loamy soil pointed to significant differences in the yielding and productivity between 'Łutówka' trees grafted on the studied rootstocks. The trees grafted on Mahaleb cherry in both studied years were characterized by significantly greater productivity than on the other rootstocks. Significantly higher yields were gathered from the trees on Mahaleb cherry than on vegetative rootstocks, and by 70% higher than on Mazzard cherry. P-HL A rootstock is of little use in the planting of 'Łutówka', which grown poorly on light soils. Besides poor growth and yielding, in longer dry periods the studies found the appearance of chlorosis of magnesium on older leaves, and even wilting of the leaves.

  18. Influence of rootstocks and pruning times on yield and on nutrient content and extraction in 'Niagara Rosada' grapevine

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    Marco Antonio Tecchio

    2014-05-01

    Full Text Available The objective of this work was to evaluate the influence of rootstocks and pruning times on yield and on nutrient content and extraction by pruned branches and harvested bunches of 'Niagara Rosada' grapevine in subtropical climate. The rootstocks 'IAC 766', 'IAC 572', 'IAC 313', 'IAC 571-6', and '106-8 Mgt' were evaluated. Treatments consisted of a combination between five rootstocks and three pruning times. At pruning, fresh and dry matter mass of branches were evaluated to estimate biomass accumulation. At harvest, yield was estimated by weighing of bunches per plant. Branches and bunches were sampled at pruning and at harvest, respectively, for nutrient content analysis. Nutrient content and dry matter mass of branches and bunches were used to estimate total nutrient extraction. 'Niagara Rosada' grapevine grafted onto the 'IAC 572' rootstock had the highest yield and dry matter mass of bunches, which were significantly different from the ones observed in 'Niagara Rosada'/'IAC 313'. 'Niagara Rosada' grafted onto the 'IAC 572' rootstock extracted the largest quantity of K, P, Mg, S, Cu, and Fe, differing from 'IAC 313' and 'IAC 766' in K and P extraction, and from '106-8 Mgt' in Mg and S extraction. Winter pruning results in higher yield, dry matter accumulation by branches, and total nutrient content and extraction.

  19. Genome wide selection in Citrus breeding.

    Science.gov (United States)

    Gois, I B; Borém, A; Cristofani-Yaly, M; de Resende, M D V; Azevedo, C F; Bastianel, M; Novelli, V M; Machado, M A

    2016-10-17

    Genome wide selection (GWS) is essential for the genetic improvement of perennial species such as Citrus because of its ability to increase gain per unit time and to enable the efficient selection of characteristics with low heritability. This study assessed GWS efficiency in a population of Citrus and compared it with selection based on phenotypic data. A total of 180 individual trees from a cross between Pera sweet orange (Citrus sinensis Osbeck) and Murcott tangor (Citrus sinensis Osbeck x Citrus reticulata Blanco) were evaluated for 10 characteristics related to fruit quality. The hybrids were genotyped using 5287 DArT_seq(TM) (diversity arrays technology) molecular markers and their effects on phenotypes were predicted using the random regression - best linear unbiased predictor (rr-BLUP) method. The predictive ability, prediction bias, and accuracy of GWS were estimated to verify its effectiveness for phenotype prediction. The proportion of genetic variance explained by the markers was also computed. The heritability of the traits, as determined by markers, was 16-28%. The predictive ability of these markers ranged from 0.53 to 0.64, and the regression coefficients between predicted and observed phenotypes were close to unity. Over 35% of the genetic variance was accounted for by the markers. Accuracy estimates with GWS were lower than those obtained by phenotypic analysis; however, GWS was superior in terms of genetic gain per unit time. Thus, GWS may be useful for Citrus breeding as it can predict phenotypes early and accurately, and reduce the length of the selection cycle. This study demonstrates the feasibility of genomic selection in Citrus.

  20. Trailers transporting oranges to processing plants move Asian citrus psyllids

    Science.gov (United States)

    Huanglongbing (citrus greening) is one of the most serious of citrus diseases. Movement of the disease occurs as a result of natural vector-borne infection and by movement of plant material. We demonstrate here that Diaphorina citri Kuwayama (vector of citrus greening pathogens) can be transported i...

  1. Current California Drought: Impact on Citrus Trees and Potential Mitigation

    Science.gov (United States)

    California is in another cycle of extended drought. The article reviews and discusses likely impact of the current drought on citrus growers and potential mitigation techniques. Citrus physiological responses to water stress is briefly reviewed. The direct impact of drought on citrus is reduced frui...

  2. First report of citrus leprosis virus nuclear type in Colombia

    Science.gov (United States)

    Citrus leprosis is a difficult viral disease causing significant damage to citrus fruit in South America and Central America. The disease is marked by dramatic lesions on fruit, leaves and stems resulting in unmarketable product. Citrus leprosis virus cytoplasmic types (CiLV-C and CiLV-C2) wer edete...

  3. Inhibition of aconitase in citrus fruit callus results in a metabolic shift towards amino acid biosynthesis

    NARCIS (Netherlands)

    Degu, A.; Hatew, B.; Nunes-Nesi, A.; Shlizerman, L.; Zur, N.; Fernie, A.R.; Blumwald, E.; Sadka, A.

    2011-01-01

    Citrate, a major determinant of citrus fruit quality, accumulates early in fruit development and declines towards maturation. The isomerization of citrate to isocitrate, catalyzed by aconitase is a key step in acid metabolism. Inhibition of mitochondrial aconitase activity early in fruit development

  4. CALOGÊNESE EM ÓVULOS DE ESPÉCIES E VARIEDADES DE CITRUS CALLUS INDUCTION FROM CITRUS SPECIES AND VARIETIES

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    ROBERTO PEDROSO DE OLIVEIRA

    2001-08-01

    Full Text Available A Embrapa Mandioca e Fruticultura vem realizando ações de pesquisa visando à obtenção de híbridos somáticos de citros, particularmente porta-enxertos, melhor adaptados às condições tropicais de cultivo brasileiras que as variedades atualmente em uso. Como objetivo principal, busca-se a seleção de genótipos tolerantes à seca e ao alumínio, tolerantes/resistentes a gomose de Phytophthora e tristeza dos citros, além de adaptados a altas densidades populacionais. Como fontes de protoplastos, vêm sendo utilizadas as tangerinas-'Cleópatra', 'Sunki' e 'Swatow', limões-'Cravo Santa Cruz' e 'Santa Bárbara', 'Volkameriano' e 'Rugoso Mazoe', laranja 'Hamlin CNPMF 04' e 'CNPMF 20', laranjas-azedas 'Comum' e 'Narrow Leaf', citrange-'Troyer', Citrus amblycarpa e Microcitrus papuana. O estudo concentrou-se na etapa de obtenção e cultivo de calos embriogênicos. Foram utilizados óvulos extraídos de frutos imaturos, empregando-se como meio de cultura o MT, adicionando-se 50 g.L-1 de sacarose e 500 mg.L-1de extrato de malte e solidificando com 7 g.L-1 1de ágar. Em geral, a indução de calos nas variedades estudadas ocorreu entre a 6ª e a 8ª semana de cultivo, com maior precocidade na laranja-‘Hamlin’, sendo que, em limão-‘Cravo’, laranja-‘Hamlin’ , tangerinas-‘Cleópatra’ e ‘Swatow’ e citrange-‘Troyer’, a porcentagem de formação de calos foi igual ou superior a 50%, destacando-se a tangerina-‘Cleópatra’ com um porcentual próximo a 70% de calogênese.Embrapa Cassava & Fruits Research with citrus aim at obtaining somatic hybrids, particularly rootstocks, better adapted to the Brazilian tropical cultivation conditions than the varieties currently in use. The main objectives are the selection of genotypes tolerant to drought and aluminum toxicity, tolerant/resistant to Phytophthora foot rot and citrus tristeza virus, besides being well adapted to high planting densities. The following varieties have being

  5. GC-MS metabolomic differentiation of selected citrus varieties with different sensitivity to citrus huanglongbing.

    Science.gov (United States)

    Cevallos-Cevallos, Juan M; Futch, David B; Shilts, Turksen; Folimonova, Svetlana Y; Reyes-De-Corcuera, José I

    2012-04-01

    Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The rapid identification of tolerant varieties is considered a critical step towards controlling HLB. GC-MS metabolite profiles were used to differentiate HLB-tolerant citrus varieties 'Poncirus trifoliata' (TR) and 'Carrizo citrange' (CAR) from HLB-sensitive varieties 'Madam Vinous sweet orange' (MV) and 'Duncan' grapefruit (DG). PCR analyses revealed that MV was the most sensitive variety followed by DG and the tolerant varieties CAR and TR. Metabolomic multivariate analysis allowed classification of the cultivars in apparent agreement with PCR results. Higher levels of the amino acids l-proline, l-serine, and l-aspartic acid, as well as the organic acids butanedioic and tetradecanoic acid, and accumulation of galactose in healthy plants were characteristic of the most sensitive variety MV when compared to all other varieties. Only galactose was significantly higher in DG when compared to the tolerant varieties TR and CAR. The tolerant varieties showed higher levels of l-glycine and mannose when compared to sensitive varieties MV and DG. Profiling of the sensitive varieties MV and DG over a 20-week period after inoculation of those with the HLB-containing material revealed strong responses of metabolites to HLB infection that differed from the response of the tolerant varieties. Significant changes of l-threonine level in the leaves from old mature flushes and l-serine, l-threonine, scyllo-inositol, hexadecanoic acid, and mannose in the leaves from young developing flushes were observed in MV. Significant changes in myo-inositol in old flushes and l-proline, indole, and xylose in new flushes were observed in DG.

  6. Bottle gourd rootstock-grafting affects nitrogen metabolism in NaCl-stressed watermelon leaves and enhances short-term salt tolerance.

    Science.gov (United States)

    Yang, Yanjuan; Lu, Xiaomin; Yan, Bei; Li, Bin; Sun, Jin; Guo, Shirong; Tezuka, Takafumi

    2013-05-01

    The plant growth, nitrogen absorption, and assimilation in watermelon (Citrullus lanatus [Thunb.] Mansf.) were investigated in self-grafted and grafted seedlings using the salt-tolerant bottle gourd rootstock Chaofeng Kangshengwang (Lagenaria siceraria Standl.) exposed to 100mM NaCl for 3d. The biomass and NO3(-) uptake rate were significantly increased by rootstock while these values were remarkably decreased by salt stress. However, compared with self-grafted plants, rootstock-grafted plants showed higher salt tolerance with higher biomass and NO3(-) uptake rate under salt stress. Salinity induced strong accumulation of nitrate, ammonium and protein contents and a significant decrease of nitrogen content and the activities of nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), and glutamate synthase (GOGAT) in leaves of self-grafted seedlings. In contrast, salt stress caused a remarkable decrease in nitrate content and the activities of GS and GOGAT, and a significant increase of ammonium, protein, and nitrogen contents and NR activity, in leaves of rootstock-grafted seedlings. Compared with that of self-grafted seedlings, the ammonium content in leaves of rootstock-grafted seedlings was much lower under salt stress. Glutamate dehydrogenase (GDH) activity was notably enhanced in leaves of rootstock-grafted seedlings, whereas it was significantly inhibited in leaves of self-grafted seedlings, under salinity stress. Three GDH isozymes were isolated by native gel electrophoresis and their expressions were greatly enhanced in leaves of rootstock-grafted seedlings than those of self-grafted seedlings under both normal and salt-stress conditions. These results indicated that the salt tolerance of rootstock-grafted seedlings might (be enhanced) owing to the higher nitrogen absorption and the higher activities of enzymes for nitrogen assimilation induced by the rootstock. Furthermore, the detoxification of ammonium by GDH when the GS/GOGAT pathway

  7. Degradation products of citrus volatile organic compounds (VOCs) acting as phagostimulants that increase probing behavior of Asian citrus psyllid

    Science.gov (United States)

    Volatile phytochemicals play a role in orientation by phytophagous insects. We studied antennal and behavioral responses of the Asian citrus psyllid, Diaphorina citri Kuwayama, vector of the citrus greening disease pathogen. Little or no response to citrus leaf volatiles was detected by electroanten...

  8. IDENTIFICATION AND QUANTIFICATION OF DIFFERENTIALLY EXPRESSED GENES ASSOCIATED WITH CITRUS BLIGHT (Citrus spp.

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    José Renato de Abreu

    2015-02-01

    Full Text Available Brazil is the largest citrus producer in the world, being responsible for more than 20% of its production, which is, however still low due to phytosanitary issues such as citrus blight. Citrus blight is an anomaly whose causes still have not yet been determined, therefore there are no efficient control measures to minimize the production losses with the use of resistant varieties being considered the most appropriate method. However, little is known about the genes involved in the defense response of the plants to this anomaly. Considering that many physiological alterations associated with plant stress responses are controlled at a transcriptional level, in this study we sought the identification and characterization of the gene expression products differentially expressed in the response to the citrus blight. Through the suppressive subtractive hybridization technique, expressed cDNA libraries were built using mRNAs isolated from "Cravo" lemon tree roots (Citrus limonia L. Osbeck under "Pera" orange (Citrus sinensis L. Osbeck of healthy and sick plants. 129 clones were obtained by subtraction and their sequences were compared in databases. 34 of them linked to proteins associated to stress processes, while the others were similar to sequences of unknown functions or did not present similarity with sequences deposited in the databases. 3 genes were selected and their expressions were studied by RT - qPCR in real-time. Plants with citrus blight presented an increase of the expression level in two of those genes, suggesting that these can be directly involved with this anomaly.

  9. Root system distribution of rootstocks under ‘Folha Murcha’ orange plant scion in subtropical climateDistribuição do sistema radicular de porta-enxertos sob laranjeira ‘Folha Murcha’ em clima subtropical

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    Neusa Maria Colauto Stenzel

    2012-06-01

    Full Text Available The aim was to study the distribution of the root system of Rangpur lime (Citrus limonia Osbeck, Rough lemon (Citrus jambluri Lush., Cleopatra mandarin (Citrus reshni Hort ex Tan. and Trifoliata (Poncirus trifoliata (L. Ralf., under ‘Folha Murcha’ orange plant scion in subtropical climate, using the auger method. The samples were taken parallel to the line of planting (row 0.5; 1.0; 1.5 and 2.0 m away from the trunk and perpendicular to the line of planting (inter-row 0.5; 1.0; 1.5; 2.0; 2.5; 3.0 and 3.5 m away from the trunk. These samples were stratified into 0 – 0.1; 0.1 – 0.2; 0.2 – 0.4; 0.4 – 0.6 m deep. Dry mass, effective depth and effective distance of the root system of plants were determined. Randomized blocks design was used with four treatments and four replications, with one plant for each plot. Cleopatra mandarin plants had the highest total mass of roots 2.0; 2.5 and 3.0 m away from the trunck in inter-row, and in superficial layers of the following sampling sites: 0.5 and 1.0 m away from the trunk towards row and 1.5 e 2.0 m away from the trunck towards inter-row. Rough lemon plants showed greater effective depth of the roots in the rows than the other rootstocks.Objetivou-se estudar a distribuição do sistema radicular dos limoeiros ‘Cravo’ (Citrus limonia Osbeck e ‘Rugoso da África’ (Citrus jambluri Lush., tangerineira ‘Cleópatra’ (Citrus reshni Hort ex Tan. e ‘Trifoliata’ (Poncirus trifoliata (L. Ralf., sob a laranjeira ‘Folha Murcha’ em clima subtropical. As amostragens foram realizadas, pelo método do trado, paralelamente à linha de plantio (entre plantas a 0,5; 1,0; 1,5 e 2,0 m de distância do tronco e perpendicularmente à linha de plantio (entrelinhas a 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 e 3,5 m de distância do tronco. Essas amostras foram estratificadas em 0 – 0,1; 0,1 – 0,2; 0,2 – 0,4; 0,4 – 0,6 m de profundidade. Foram determinadas: massa seca, profundidade e dist

  10. Desenvolvimento vegetativo e produtivo da cultivar 'Maciel' em diferentes porta-enxertos Vegetative and productive growth of peach tree cv. 'Maciel' grafted in different rootstocks

    Directory of Open Access Journals (Sweden)

    Luciano Picolotto

    2012-06-01

    -enxertos.The use of an appropriate rootstock depends on the knowledge of its affinity with the cultivar scion as well as its influence on liveliness and productiveness. The purpose of this research was to evaluate the vegetative and -productive development, and fruit quality of the cv. Study was to evaluate the vegetative growth, fruit production and quality of cv. 'Maciel' grafted on different peach rootstocks. The cultivars used as rootstocks were seeds from industry, 'Capdeboscq', 'Aldrighi', 'Tsukuba 1', 'a clone of Okinawa', 'Okinawa clone 12', and 'Rubira' 'Nemaguard' and as canopy it was used cv 'Maciel'. It was measured trunk diameter, canopy volume, amount of chlorophyll, pruning intensity, productivity, mass, and color of pulp fruit firmness, TSS, TA and TSS/TA ratio. The experimental design was randomized blocks with eight levels for the factor rootstock, each consisting of three replications with five plants per replicate. It was observed in the last assessment in 2008, the difference in diameter of the trunk between the rootstocks, especially 'Industria' (47.2mm and 'Tsukuba' (46.8mm. In the canopy volume the highlight among the rootstocks occurred with 'Industria' (1,60m³ and 'Nemaguard' (1,63m³. The amount of chlorophyll was similar with 'Nemaguard', 'Tsukuba 1', 'Okinawa clone 1', 'Rubira' and 'Indústria'. Fruit weight was greater with 'Rubira' (143g and 'Tsukuba' (135g in 2007 and in 2008 and in 2008 most 'Okinawa clone 12' (73g, 'Capdeboscq' (83g, 'Aldrighi' (81g and 'Nemaguard' (82g. There was variation in productivity in production cycles, the highlight occurred in 2007 with 'Tsukuba 1' (0.32ton ha-1 and in 2008 with 'Industry' (8.6tons ha-1. With the 'Okinawa clone 12' it was observed higher firmness (12.1 and 11.8 pounds in 2007 and 2008, respectively. Highest TSS / ATT stood out with 'Tsukuba 1' (18.3. Based on the differential responses it was concluded that the vegetative growth and fruit quality of cv. 'Maciel' are affected by the rootstocks.

  11. In Vitro and In Vivo Antibacterial Activity of Some Organic and Inorganic Salts Against Asiatic Citrus Canker Agent Xanthomonas Citri Subsp. Citri

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    Vahideh Hasabi

    2014-06-01

    Full Text Available Asiatic citrus canker caused by Xanthomonas citri subsp. citri is becoming a disease of high economic impact, affecting all types of important citrus crops. In this study, the potential antibacterial activity of ten organic and inorganic salts on X. citri subsp. citri and on citrus canker disease development was evaluated. Among the salt compounds, copper, iron and zinc inorganic salts particularly zinc (with the highest diameter of inhibition, the lowest MIC and MBC values and the highest bacterial growth inhibitory effect had direct antibacterial activity and strongly reduced the development of canker disease and bacterial population of lime plants.

  12. Isolation and Functional Characterization of a Lycopene β-cyclase Gene Promoter from Citrus.

    Science.gov (United States)

    Lu, Suwen; Zhang, Yin; Zheng, Xiongjie; Zhu, Kaijie; Xu, Qiang; Deng, Xiuxin

    2016-01-01

    Lycopene β-cyclases are key enzymes located at the branch point of the carotenoid biosynthesis pathway. However, the transcriptional regulatory mechanisms of LCYb1 in citrus with abundant carotenoid accumulation are still unclear. To understand the molecular basis of CsLCYb1 expression, we isolated and functionally characterized the 5' upstream sequences of CsLCYb1 from citrus. The full-length CsLCYb1 promoter and a series of its 5' deletions were fused to the β-glucuronidase (GUS) reporter gene and transferred into different plants (tomato, Arabidopsis and citrus callus) to test the promoter activities. The results of all transgenic species showed that the 1584 bp upstream region from the translational start site displayed maximal promoter activity, and the minimal promoter containing 746 bp upstream sequences was sufficient for strong basal promoter activity. Furthermore, the CsLCYb1 promoter activity was developmentally and tissue-specially regulated in transgenic Arabidopsis, and it was affected by multiple hormones and environmental cues in transgenic citrus callus under various treatments. Finer deletion analysis identified an enhancer element existing as a tandem repeat in the promoter region between -574 to -513 bp and conferring strong promoter activity. The copy numbers of the enhancer element differed among various citrus species, leading to the development of a derived simple sequence repeat marker to distinguish different species. In conclusion, this study elucidates the expression characteristics of the LCYb1 promoter from citrus and further identifies a novel enhancer element required for the promoter activity. The characterized promoter fragment would be an ideal candidate for genetic engineering and seeking of upstream trans-acting elements.

  13. Isolation and functional characterization of a lycopene β-cyclase gene promoter from citrus

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    Suwen Lu

    2016-09-01

    Full Text Available Lycopene β-cyclases are key enzymes located at the branch point of the carotenoid biosynthesis pathway. However, the transcriptional regulatory mechanisms of LCYb1 in citrus with abundant carotenoid accumulation are still unclear. To understand the molecular basis of CsLCYb1 expression, we isolated and functionally characterized the 5’ upstream sequences of CsLCYb1 from citrus. The full-length CsLCYb1 promoter and a series of its 5’ deletions were fused to the β-glucuronidase (GUS reporter gene and transferred into different plants (tomato, Arabidopsis and citrus callus to test the promoter activities. The results of all transgenic species showed that the 1584 bp upstream region from the translational start site displayed maximal promoter activity, and the minimal promoter containing 746 bp upstream sequences was sufficient for strong basal promoter activity. Furthermore, the CsLCYb1 promoter activity was developmentally and tissue-specially regulated in transgenic Arabidopsis, and it was affected by multiple hormones and environmental cues in transgenic citrus callus under various treatments. Finer deletion analysis identified an enhancer element existing as a tandem repeat in the promoter region between -574 to -513 bp and conferring strong promoter activity. The copy numbers of the enhancer element differed among various citrus species, leading to the development of a derived simple sequence repeat (SSR marker to distinguish different species. In conclusion, this study elucidates the expression characteristics of the LCYb1 promoter from citrus and further identifies a novel enhancer element required for the promoter activity. The characterized promoter fragment would be an ideal candidate for genetic engineering and seeking of upstream trans-acting elements.

  14. Deciphering the Bacterial Microbiome in Huanglongbing-Affected Citrus Treated with Thermotherapy and Sulfonamide Antibiotics.

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    Chuanyu Yang

    Full Text Available Huanglongbing (HLB is a serious citrus disease that threatens the citrus industry. In previous studies, sulfonamide antibiotics and heat treatment suppressed 'Candidatus Liberibacter asiaticus' (Las, but did not completely eliminate the Las. Furthermore, there are few reports studying the bacterial microbiome of HLB-affected citrus treated by heat and sulfonamide antibiotics. In this study, combinations of heat (45°C or 40°C and sulfonamide treatment (sulfathiazole sodium-STZ, or sulfadimethoxine sodium-SDX were applied to HLB-affected citrus. The bacterial microbiome of HLB-affected citrus following thermotherapy and/or chemotherapy was characterized by PhyloChipTMG3-based metagenomics. Our results showed that the combination of thermotherapy at 45°C and chemotherapy with STZ and SDX was more effective against HLB than thermotherapy alone, chemotherapy alone, or a combination of thermotherapy at 40°C and chemotherapy. The PhyloChipTMG3-based results indicated that 311 empirical Operational Taxonomic Units (eOTUs were detected in 26 phyla. Cyanobacteria (18.01% were dominant after thermo-chemotherapy. Thermotherapy at 45°C decreased eOTUs (64.43% in leaf samples, compared with thermotherapy at 40°C (73.96% or without thermotherapy (90.68% and it also reduced bacterial family biodiversity. The eOTU in phylum Proteobacteria was reduced significantly and eOTU_28, representing "Candidatus Liberibacter," was not detected following thermotherapy at 45°C. Following antibiotic treatment with SDX and STZ, there was enhanced abundance of specific eOTUs belonging to the families Streptomycetaceae, Desulfobacteraceae, Chitinophagaceae, and Xanthomonadaceae, which may be implicated in increased resistance to plant pathogens. Our study further develops an integrated strategy for combating HLB, and also provides new insight into the bacterial microbiome of HLB-affected citrus treated by heat and sulfonamide antibiotics.

  15. 南方山区集中连片大规模开发果园的建议--由安远县柑橘黄龙病引起的反思%Advice to Concentrated Mass Development of Orchard for the Southern Mountainous Area---Caused by Outbreaks of Citrus huanglongbing in Anyuan County

    Institute of Scientific and Technical Information of China (English)

    杨文侠; 唐焕庆

    2014-01-01

    Citrus huanglongbing (HLB, yellow shoot disease) outbroke in large area of Anyuan County in Jiangxi Province in 2013, the occurrence history and damage of HLB were summarized in Anyuan County, as well as the reason of disease occurrence was analyzed emphatically. Introspection and suggestion was put forward for the large scale cultivation of southern mountain areas developing citrus industry, it has been more explicit in linking overdevelopment with the disaster. It would be helpful for providing theoretical references for the balance between ecological protection and economic development in other regions.%2013年柑橘黄龙病在江西省安远县大面积爆发,通过调查,总结了安远柑橘黄龙病发生历史,爆发危害,重点分析了发病原因,就南方山区规模化连片种植发展柑橘产业提出深思和建议,更加明确地将过度开发与此次灾害联系起来。为其他地区今后在生态保护与经济发展权衡上提供理论参考。

  16. Tissue-specific high expression of TFL1 correlates with citrus juvenility

    Science.gov (United States)

    Early flowering is a desirable trait for many horticultural crops including citrus, which are woody trees that can have a juvenile phase from several to over 10 years. Research on floral organ development has identified genes critical to the regulation of juvenility/maturity. TFL1 is a negative regu...

  17. ENZYMATIC KINETIC STUDY HYDROLASE FROM CITRUS

    Directory of Open Access Journals (Sweden)

    Israel Hernández

    2015-09-01

    Full Text Available In this paper the degrading activity of enzymes derived from orange peels (Citrus x sinensis, grapefruit (Citrus paradise and pineapple (Ananas comosus on the organic matter in wastewater is evaluated. This activity is measured indirectly by quantifying the biochemical oxygen demand (COD before and after degradation process based on a period of time using the HACH DR / 2010, and then the kinetic study was performed by the differential method and integral with the experimental data, obtaining a reaction order of 1 to pectinase (orange, and order 2 for bromelain (pineapple.

  18. Mineral Content in Leaves of Tomato Plants Grafted on Solanum Rootstocks

    OpenAIRE

    松添, 直隆; 間, 浩美; 花田, 勝美; モハメド, アリ, エル, サイド, アリ; 大久保, 敬; 藤枝, 國光

    1995-01-01

    Nutrient uptake of tomato plants cv. Momotaro grafted on Solanum sisymbriifoliulm, S. torvum and S. toxicarium which are resistant to soil-born disease were compared with tomato grafted on its own root, a tomato/tomato, scion/rootstock combination. Mineral content in leaves of tomato/S. sisymbriifoliulm was nearly equal to that of tomato/tomato. In leaves of tomato/S. torvum, nitrogen content was higher, and magnesium content was lower than those of tomato/tomato. Furthermore, phosphorus and ...

  19. Chromosomal localization of ribosomal DNA sequences in an apple rootstock using a digoxygenin detection system

    Institute of Scientific and Technical Information of China (English)

    ZHUJIMEI; SEGARDINER

    1995-01-01

    A 6kb rDNA probe comprising the 18S coding plus spacer sequences has been hybridized to the metaphase chromosomes of apple rootstock cultivar MM106 demonstrating the localization of ribosomal gene arrays in the vicinity of the telomeric regions of the short arms of chromosomes 6 and 14.The in situ results using digoxygenin labelling coupled to an alkaline phosphatase immunoassay were confirmed by silver staining for NORs and nucleoli.This study demonstrates the feasibility of molecular cytogenetic analysis of very small chromosomes(1.0-2.7μm) of apple.

  20. Apple Rootstock New Variety Chistock #1%苹果砧木新品种中砧1号

    Institute of Scientific and Technical Information of China (English)

    韩振海; 王忆; 张新忠; 许雪峰; 孙扬吾; 沈隽

    2013-01-01

    The iron has a very important role in the growth and development of the plant,iron deficiency causes chlorosis in apple trees.The main producing areas of apple in China just iron deficiency,therefore,filter out iron-efficient resources from rich apple germplasm resources,and breeding new varieties of apple rootstocks through breeding means is fundamental pathway to solve due to iron deficiency affected yield and quality of apple production.Since 1984,the project team screened iron-efficient genotypes from 40 apple stocks and found Malus xiaojinensis Cheng et Jiang,grow normally and do not exhibit symptoms of chlorosisin in conditions of very low Fe content,was considered to be an excellent germplasm with tolerance to iron deficiency.Subsequently,open pollinated hybrids groups were established on the basis of M.xiaojinensis Cheng et Jiang seedlings.In 1990,excellent grades was obtained through original selection from natural seedlings.Then after multiple selection and comparison test,bred apple clonal rootstocks Chistock #1.Chistock #1 is a tetraploid in chromosome number (2n =4x =68),with a capacity of apomixis,and setting rate above 85% after emasculation bagged.Then with excellent grafting compatibility,seedling dry good standing and strong solid ground,semi-dwarf,dwarf extent,effects and yield capacity were similar with simi-dwarfing apple rootstock M7.Sweet fruit flavor,palatability,and excellent quality.Resist apple early defoliation disease and branches ring rot,high resistance to apple Chlorotic leaf spot virus(CLSV),Stem pitting virus(SPV) and the Stem groove virus(SGV) and other latent virus.Chistock #1 can effectively prevent etiolation due to iron deficiency as apple rootstock in the lime parent material soil areas.%铁是植物生长的必需微量元素,缺铁导致苹果发生失绿症,生长结果受到影响.我国苹果主产区恰在缺铁区域范围内,因此,从丰富的苹果种质资源中筛选出铁高效型资源,通

  1. Soil organic matter on citrus plantation in Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; Pereira, Paulo; Novara, Agata; Prosdocimi, Massimo

    2015-04-01

    Citrus plantations in Eastern Spain are the main crop and Valencia region is the largest world exporter. The traditional plantation are located on flood irrigated areas and the new plantation are located on slopes were drip irrigation is the source of the wetting. It has been demonstrate that the citrus plantations contribute to high erosion rates on slopes (Cerdà et al., 2009b) as it is usual on agriculture land (Cerdà et al., 2009a), but when organic farming is present the soil erosion is much lower (Cerdà and Jurgensen, 2008; Cerdà et al., 2009; Cerdà and Jurgensen, 2011). This is a worldwide phenomenon (Wu et al., 2007; Wu et al., 2011; Xu et al., 2010; Xu et al., 2012a; Xu et al., 2012b), which are a key factor of the high erosion rates in rural areas (García Orenes et al., 2009: García Orenes et al., 20010; García Orenes et al., 2012; Haregewyn et al., 2013; Zhao et al., 2013). The key factor of the contrasted response of soils to the rain in citrus is the organic matter cover. This is why the Soil Erosion and Degradation Research Team developed a survey to determine the soil erosion rates on citrus orchards under different managements. A hundred of samples were collected in a citrus plantation on slope under conventional management (Chemical management), one on organic farming, one on traditional flood irrigated organic farming and one on traditional chemical flooding farm. The organic farming soils were treated with 10000 Kg ha-1 of manure yearly. The results show that the mean soil organic matter content was 1.24 %, 3.54%, 5,43% and 2.1% respectively, which show a clear impact of organic farming in the recovery of the soil organic matter. meanwhile the on the slopes and the flood-irrigated soils are Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7- ENV-2013- supported this research. References Cerdà, A., Flanagan, D.C., le Bissonnais

  2. Produção de porta-enxertos em tubetes e enxertia precoce da pinheira (Annona squamosa L. Production of rootstocks in tubettes and early grafting of sugar-apple (Annona squamosa L.

    Directory of Open Access Journals (Sweden)

    Eurico Eduardo Pinto de Lemos

    2010-09-01

    Full Text Available O objetivo deste trabalho foi estabelecer um protocolo para a enxertia precoce de pinheira em porta-enxertos produzidos em tubetes como substituto do tradicional sistema de enxertia que utiliza porta-enxertos de 12 meses produzidos em sacolas plásticas. O trabalho foi conduzido com três métodos de enxertia (borbulhia em escudo, garfagem de topo em fenda cheia e garfagem lateral em fenda cheia e quatro idades dos porta-enxertos (3; 5; 7 e 9 meses. Os porta-enxertos foram avaliados durante nove meses com relação às variáveis: comprimento da planta, diâmetro do caule, número de folhas e área foliar. Cada procedimento de enxertia foi avaliado por 30 dias através da percentagem de pegamento. Os porta-enxertos produzidos nos tubetes maiores apresentaram-se mais desenvolvidos para todas as variáveis, todavia a percentagem de pegamento dos enxertos foi mais influenciada pelo método de enxertia do que pelo tamanho de tubete. A garfagem de topo em fenda cheia mostrou-se como o melhor método para a enxertia precoce, pois já aos três meses de idade dos porta-enxertos apresentou taxa de pegamento de 96,69%. O método de garfagem lateral em fenda cheia apresentou taxas semelhantes a partir dos cinco meses de idade dos porta-enxertos. O método de borbulhia apresentou baixo pegamento inicial (The objective of this work was to establish a protocol for early grafting in sugar apple seedlings developed in small capacity plastic tubettes as a substitute for the traditional grafting system that uses 12 months-old seedlings developed in plastic bags. The work was carried out with three budding/grafting methods (chip budding, split graft and side-stub graft and four rootstocks ages (3, 5, 7 and 9 months. The rootstocks were evaluated for 9 months with regard to the following variables: length of the plant, diameter of stem, leaf number and leaf area. Each budding/grafting procedure was evaluated after 30 days and the percentage of union. The

  3. Recovery and characterization of a Citrus clementina Hort. ex Tan. 'Clemenules' haploid plant selected to establish the reference whole Citrus genome sequence

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    Navarro Luis

    2009-08-01

    Full Text Available Abstract Background In recent years, the development of structural genomics has generated a growing interest in obtaining haploid plants. The use of homozygous lines presents a significant advantage for the accomplishment of sequencing projects. Commercial citrus species are characterized by high heterozygosity, making it difficult to assemble large genome sequences. Thus, the International Citrus Genomic Consortium (ICGC decided to establish a reference whole citrus genome sequence from a homozygous plant. Due to the existence of important molecular resources and previous success in obtaining haploid clementine plants, haploid clementine was selected as the target for the implementation of the reference whole genome citrus sequence. Results To obtain haploid clementine lines we used the technique of in situ gynogenesis induced by irradiated pollen. Flow cytometry, chromosome counts and SSR marker (Simple Sequence Repeats analysis facilitated the identification of six different haploid lines (2n = x = 9, one aneuploid line (2n = 2x+4 = 22 and one doubled haploid plant (2n = 2x = 18 of 'Clemenules' clementine. One of the haploids, obtained directly from an original haploid embryo, grew vigorously and produced flowers after four years. This is the first haploid plant of clementine that has bloomed and we have, for the first time, characterized the histology of haploid and diploid flowers of clementine. Additionally a double haploid plant was obtained spontaneously from this haploid line. Conclusion The first haploid plant of 'Clemenules' clementine produced directly by germination of a haploid embryo, which grew vigorously and produced flowers, has been obtained in this work. This haploid line has been selected and it is being used by the ICGC to establish the reference sequence of the nuclear genome of citrus.

  4. Transcriptome profiling of citrus fruit response to huanglongbing disease.

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    Federico Martinelli

    Full Text Available Huanglongbing (HLB or "citrus greening" is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of photosynthesis and in ATP synthesis. Activation of protein degradation and misfolding processes were observed at the transcriptomic level. Transcripts for heat shock proteins were down-regulated at all disease stages, resulting in further protein misfolding. HLB strongly affected pathways involved in source-sink communication, including sucrose and starch metabolism and hormone synthesis and signaling. Transcription of several genes involved in the synthesis and signal transduction of cytokinins and gibberellins was repressed while that of genes involved in ethylene pathways was induced. CaLas infection triggered a response via both the salicylic acid and jasmonic acid pathways and increased the transcript abundance of several members of the WRKY family of transcription factors. Findings focused on the fruit provide valuable insight to understanding the mechanisms of the HLB-induced fruit disorder and eventually developing methods based on small molecule applications to mitigate its devastating effects on fruit production.

  5. Transcriptome profiling of citrus fruit response to huanglongbing disease.

    Science.gov (United States)

    Martinelli, Federico; Uratsu, Sandra L; Albrecht, Ute; Reagan, Russell L; Phu, My L; Britton, Monica; Buffalo, Vincent; Fass, Joseph; Leicht, Elizabeth; Zhao, Weixiang; Lin, Dawei; D'Souza, Raissa; Davis, Cristina E; Bowman, Kim D; Dandekar, Abhaya M

    2012-01-01

    Huanglongbing (HLB) or "citrus greening" is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of photosynthesis and in ATP synthesis. Activation of protein degradation and misfolding processes were observed at the transcriptomic level. Transcripts for heat shock proteins were down-regulated at all disease stages, resulting in further protein misfolding. HLB strongly affected pathways involved in source-sink communication, including sucrose and starch metabolism and hormone synthesis and signaling. Transcription of several genes involved in the synthesis and signal transduction of cytokinins and gibberellins was repressed while that of genes involved in ethylene pathways was induced. CaLas infection triggered a response via both the salicylic acid and jasmonic acid pathways and increased the transcript abundance of several members of the WRKY family of transcription factors. Findings focused on the fruit provide valuable insight to understanding the mechanisms of the HLB-induced fruit disorder and eventually developing methods based on small molecule applications to mitigate its devastating effects on fruit production.

  6. Yield and quality responses of citrus (Citrus reticulate) and tea (Podocarpus fleuryi Hickel.) to compound fertilizers

    Institute of Scientific and Technical Information of China (English)

    WANG Rui; SHI Xue-gen; WEI You-zhang; YANG Xiao-e; UOTI Juhani

    2006-01-01

    Experiments were carried out with citrus (Citrus reticulate) and tea (Podocarpus fleuryi Hickel.) to studythe effects of compound fertilizers on their yieldsand quality. In the citrus experiment, application of compound fertilizers increased available P,K and Mg contents in soil but decreased alkali-hydrolyzable N contents in soil and N, P and K contents in leaves. In the tea experiment, application of compound fertilizers increased available P, K and Mg contents in soil and N, P, K and Mg contents in leaves but decreased alkali-hydrolyzable N in soil compared with the urea treatment. Application of compound fertilizers could improve the quality of citrus and tea, increase their yields and enhance their economical profits significantly. Compared with the control, application of compound fertilizers increased citrus yields by 6.31, 12.94 and 17.69 t/ha, and those of tea by 0.51, 0.86 and 1.30 t/ha, respectively. Correspondingly, profits were increased by 21.4% to 61.1% for citrus and by 10.0% to 15.7% for tea.Optimal rates of compound fertilizers were recommended for both crops.

  7. Preliminary Studies on Species and Distribution of Citrus Viroids in China

    Institute of Scientific and Technical Information of China (English)

    WANG Xue-feng; ZHOU Chang-yong; TANG Ke-zhi; LAN Jian-qiang; ZHOU Yan; LI Zhon-gan

    2008-01-01

    Citrus viroids are the small but economically important RNA pathogens.For investigating their occurrence and distribution in China,65 viroid samples collected from 8 major citrus cultivated regions were evaluated using one-step or multiplex one-step RT-PCR and biological indexing for specifically detection of Citrus exocortis viroid (CEVd),Citrus bent leaf viroid (CBLVd),Hop stunt viroid (HSVd),Citrus viroid-ⅢI (CVd-Ⅲ) and Citrus viroid-Ⅳ (CVd-Ⅳ).The results showed that there were at least 4 kinds of citrus viroids (CEVd,CBLVd,HSVd,and CVd-Ⅲ) on citrus trees in China.Most of the infected citrus plants harbored more than one viroid species,and two plants were infected with up to 4 citrus viroids.Sweet orange was more frequently infected by viroids than other citrus varieties.It is the preliminary report on the species and distribution of citrus viroids in China.

  8. The role of 1-deoxy-d-xylulose-5-phosphate synthase and phytoene synthase gene family in citrus carotenoid accumulation.

    Science.gov (United States)

    Peng, Gang; Wang, Chunyan; Song, Song; Fu, Xiumin; Azam, Muhammad; Grierson, Don; Xu, Changjie

    2013-10-01

    Three 1-deoxy-D-xylulose-5-phosphate synthases (DXS) and three phytoene synthases (PSY) were identified in citrus, from Affymetrix GeneChip Citrus Genome Array, GenBank and public orange genome databases. Tissue-specific expression analysis of these genes was carried out on fruit peel and flesh, flower and leaf of Satsuma mandarin (Citrus unshiu Marc.) in order to determine their roles in carotenoid accumulation in different tissues. Expression of CitDXS1 and CitPSY1 was highest in all test tissues, while that of CitDXS2 and CitPSY2 was lower, and that of CitDXS3 and CitPSY3 undetectable. The transcript profiles of CitDXS1 and CitPSY1 paralleled carotenoid accumulation in flesh of Satsuma mandarin and orange (Citrus sinensis Osbeck) during fruit development, and CitPSY1 expression was also associated with carotenoid accumulation in peel, while the CitDXS1 transcript level was only weakly correlated with carotenoid accumulation in peel. Similar results were obtained following correlation analysis between expression of CitDXS1 and CitPSY1 and carotenoid accumulation in peel and flesh of 16 citrus cultivars. These findings identify CitPSY1 and CitDXS1 as the main gene members controlling carotenoid biosynthesis in citrus fruit. Furthermore, chromoplasts were extracted from flesh tissue of these citrus, and chromoplasts of different shape (spindle or globular), different size, and color depth were observed in different cultivars, indicating chromoplast abundance, number per gram tissue, size and color depth were closely correlated with carotenoid content in most cultivars. The relationship between carotenoid biosynthesis and chromoplast development was discussed.

  9. Ecology of the Asian citrus pysllid

    Science.gov (United States)

    Host selection by psyllids in general appears to involve taste rather than olfaction. Adults are often less discriminating than nymphs. A priori, there is good reason to doubt that Asian citrus psyllid (ACP) uses a long-distance sex pheromone or that ACP orients to host plant volatiles over large (m...

  10. Rheology and composition of processed citrus fiber

    Science.gov (United States)

    While fibrous byproducts are abundant in supply, using them in food products in such a way to not degrade taste or texture can be challenging. Citrus fibers have been shown to have high water holding and viscous properties. However, to better incorporate dried orange pulp into foods, their propert...

  11. Digital PCR for detection of citrus pathogens

    Science.gov (United States)

    Citrus trees are often infected with multiple pathogens of economic importance, especially those with insect or mite vectors. Real-time/quantitative PCR (qPCR) has been used for high-throughput detection and relative quantification of pathogens; however, target reference or standards are required. I...

  12. New Pseudomonas spp. Are Pathogenic to Citrus.

    Science.gov (United States)

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described.

  13. Isolation and characterization of beneficial bacteria associated with citrus roots in Florida.

    Science.gov (United States)

    Trivedi, Pankaj; Spann, Timothy; Wang, Nian

    2011-08-01

    Cultivable diversity of bacteria associated with citrus was investigated as part of a larger study to understand the roles of beneficial bacteria and utilize them to increase the productive capacity and sustainability of agro-ecosystems. Citrus roots from Huanglongbing (HLB) diseased symptomatic and asymptomatic citrus were used in this study. A total of 227 and 125 morphologically distinct colonies were isolated and characterized from HLB asymptomatic and symptomatic trees, respectively. We observed that the frequency of bacterial isolates possessing various plant beneficial properties was significantly higher in the asymptomatic samples. A total of 39 bacterial isolates showing a minimum of five beneficial traits related to mineral nutrition [phosphate (P) solubilization, siderophore production, nitrogen (N) fixation], development [indole acetic acid (IAA) synthesis], health [production of antibiotic and lytic enzymes (chitinase)], induction of systemic resistance [salicylic acid (SA) production], stress relief [production of 1-amino-cyclopropane-1-carboxylate deaminase] and production of quorum sensing [N-acyl homoserine lactones] signals were characterized. A bioassay using ethidium monoazide (EMA)-qPCR was developed to select bacteria antagonistic to Candidatus Liberibacter asiaticus. Using the modified EMA-qPCR assay, we found six bacterial isolates showing maximum similarity to Paenibacillus validus, Lysinibacillus fusiformis, Bacillus licheniformis, Pseudomonas putida, Microbacterium oleivorans, and Serratia plymutica could significantly reduce the population of viable Ca. L. asiaticus in HLB symptomatic leaf samples. In conclusion, we have isolated and characterized multiple beneficial bacterial strains from citrus roots which have the potential to enhance plant growth and suppress diseases.

  14. Soluble Sugars and Sucrose-Metabolizing Enzymes Related to Cold Acclimation of Sweet Cherry Cultivars Grafted on Different Rootstocks

    Directory of Open Access Journals (Sweden)

    Ece Turhan

    2012-01-01

    Full Text Available The bark tissues were collected from 4-year-old sweet cherry trees cvs. 0900 Ziraat and Lambert grafted on Gisela 5 and Mazzard rootstocks in cold-acclimated (CA and nonacclimated (NA stages. Bark tissues subjected to 4°C and −5°C injured to a limited extent in both stages. However, more than 50% injury occurred by temperatures equal to or colder than −15°C only in NA period. Total soluble sugar (TSS, reducing sugars, and sucrose contents were higher in CA than those in NA stages in all samples. The activities of acid invertase (EC 3.2.1.26 and sucrose synthase (SS (EC 2.4.2.13 enzymes were higher in NA stage than those in CA stage. Considering the rootstocks, reducing sugars were higher in both cultivars grafted on Gisela 5 whereas sucrose contents were higher in both cultivars grafted on Mazzard. However, the enzyme activities of both cultivars were higher on Mazzard rootstock than on Gisela 5. In conclusion, cold hardiness of sweet cherry graft combinations was suggested by increasing their TSS, reducing sugars, and sucrose contents significantly in the CA stage. Moreover, acid invertase and SS are down regulated during cold acclimation. Indeed the results suggested that Mazzard is more cold-hardy rootstock than Gisela 5.

  15. Can Pierce’s disease resistance introgressed into Vitis vinifera be translocated from a resistant rootstock to a susceptible scion?

    Science.gov (United States)

    The goal of this research is to evaluate the potential of a non-transgenic, PD-resistant Vitis vinifera selection used as an experimental rootstock to confer systemic resistance to PD-susceptible V. vinifera scions. Source of PD-susceptible plant material was the wine grape variety ‘Chardonnay’, kno...

  16. The influence of rootstock and time of harvest on the fruit quality during storage of in two grapefruit cultivars

    Directory of Open Access Journals (Sweden)

    Francisca Ligia de Castro Machado

    2015-08-01

    Full Text Available The effects of the ‘Cleopatra’ mandarin and ‘Swingle’ citrumelo rootstocks and time of harvest on the quality of cold-stored (13°C and 90% R.H. ‘Ruby Red’ and ‘Star Ruby’ grapefruit grown under the tropical conditions prevalent in Ceará state, Brazil, were evaluated. Fruit quality was assessed by mass loss and peel color, the percentage of juice, soluble solids, titratable acidity, pH, maturity index, and ascorbic acid content. The results suggested that ‘Ruby Red’ and ‘Star Ruby’ grapefruit presented similar amounts of soluble solids, pH, titratable acidity and ascorbic acid levels at harvest, and the trends over the course of storage followed similar patterns for both cultivars, regardless of rootstock. The influence of scion-rootstock combination on the studied variables was dependent on the time of harvest. The peel color of ‘Ruby Red’ grafted on ‘Swingle’ citrumelo is more vivid and redder when harvested in October than when harvested in August. ‘Ruby Red’ and ‘Star Ruby’ grapefruit harvested in October are sweeter, less acidic, juicier, and richer in ascorbic acid than those harvested in August. ‘Cleopatra’ mandarin rootstock might favor ascorbic acid levels at harvest, but the fruit may lose more weight during storage.

  17. Rooting of herbaceous minicuttings of peach rootstock under effect of indolebutyric acid (IBA

    Directory of Open Access Journals (Sweden)

    Cari Rejane Fiss Timm

    2015-02-01

    Full Text Available The use of rootstocks resulting from sexual propagation is a major problem that peach crop has in Brazil, reflecting the lack of plant homogeneity, which compromises the productivity of orchards. The clonal propagation is a promising alternative for the production of homogeneous seedlings with low cost and speed, as well as the maintenance of important agronomic characteristics. Therefore, the study aimed to assess the feasibility of propagation of rootstocks of Nemared, Flordaguard and Okinawa peach cultivars through herbaceous minicuttings, testing different concentrations of IBA (0; 1,000; 2,000; and 3,000mg.L-1. The minicuttings were immersed in the solution for five seconds and, then, placed in clear plastic containers containing medium grained vermiculite. The experiment was conducted with four replications of 20 minicuttings in the greenhouse. In 45 days, it was observed that Nemared obtained 76% of rooting with 1,000 mg.L-1of IBA, not differing from Flordaguard with 66%. The estimated dose of IBA for maximum rooting was 1,590 mg.L-1.

  18. Some rootstocks improve pepper tolerance to mild salinity through ionic regulation.

    Science.gov (United States)

    Penella, Consuelo; Nebauer, Sergio G; Quiñones, Ana; San Bautista, Alberto; López-Galarza, Salvador; Calatayud, Angeles

    2015-01-01

    Grafting has been proposed as an interesting strategy that improves the responses of crops under salinity. In pepper, we reported increased fruit yield of the commercial 'Adige' cultivar under salinity when grafted onto accessions Capsicum chinense Jacq. 'ECU-973' (12) and Capsicum baccatum L. var. pendulum 'BOL-58' (14), whereas no effect was observed when grafted onto accession Capsicum annuum L var. 'Serrano' (5). We also analysed the physiological and biochemical mechanisms related to the tolerance conferred by these rootstocks. Responses to salinity (40 mM NaCl) were studied in the different plant combinations for 30 days by determining water relations, mineral content, proline accumulation, photosynthetic parameters, nitrate reductase activity and antioxidant capacity. Higher salt tolerance was achieved when the 'Adige' cultivar was grafted onto the 12 genotype, which allowed not only lower Na(+) and Cl(-) accumulation in the scion, but also ion selectivity maintenance, particularly Na(+)/K(+) discrimination. These traits led to a minor negative impact on photosynthesis, nitrate reductase activity and lipid peroxidation in grafted scion leaves. This work suggests that using tolerant pepper rootstocks that maintain the scion's ion homeostasis is a promising strategy to provide salinity tolerance and can consequently improve crop yield.

  19. Quantitative distribution of 'Candidatus Liberibacter asiaticus' in citrus plants with citrus huanglongbing.

    Science.gov (United States)

    Li, Wenbin; Levy, Laurene; Hartung, John S

    2009-02-01

    Citrus huanglongbing (HLB), or greening disease, is strongly associated with any of three nonculturable gram-negative bacteria belonging to 'Candidatus Liberibacter spp.' 'Ca. Liberibacter spp.' are transmitted by citrus psyllids to all commercial cultivars of citrus. The diseases can be lethal to citrus and have recently become widespread in both São Paulo, Brazil, and Florida, United States, the locations of the largest citrus industries in the world. Asiatic HLB, the form of the disease found in Florida, is associated with 'Ca. Liberibacter asiaticus' and is the subject of this report. The nonculturable nature of the pathogen has hampered research and little is known about the distribution of 'Ca. L. asiaticus' in infected trees. In this study, we have used a quantitative polymerase chain reaction assay to systematically quantify the distribution of 'Ca. L. asiaticus' genomes in tissues of six species of citrus either identified in the field during survey efforts in Florida or propagated in a greenhouse in Beltsville, MD. The populations of 'Ca. L. asiaticus' inferred from the distribution of 16S rDNA sequences specific for 'Ca. L. asiaticus' in leaf midribs, leaf blades, and bark samples varied by a factor of 1,000 among samples prepared from the six citrus species tested and by a factor of 100 between two sweet orange trees tested. In naturally infected trees, above-ground portions of the tree averaged 10(10) 'Ca. L. asiaticus' genomes per gram of tissue. Similar levels of 'Ca. L. asiaticus' genomes were observed in some but not all root samples from the same plants. In samples taken from greenhouse-inoculated trees, levels of 'Ca. L. asiaticus' genomes varied systematically from 10(4) genomes/g at the graft inoculation site to 10(10) genomes/g in some leaf petioles. Root samples from these trees also contained 'Ca. L. asiaticus' at 10(7) genomes/g. In symptomatic fruit tissues, 'Ca. L. asiaticus' genomes were also readily detected and quantified. The highest

  20. Citrus tristeza virus-host interactions

    Directory of Open Access Journals (Sweden)

    William O. Dawson

    2013-05-01

    Full Text Available Citrus tristeza virus (CTV is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or symptomless in most of their host range. There is little understanding of how the virus causes severe disease in some citrus and none in others. Movement and distribution of CTV differs considerably from that of well-studied viruses of herbaceous plants where movement occurs largely through adjacent cells. In contrast, CTV systemically infects plants mainly by long-distance movement with only limited cell-to-cell movement. The virus is transported through sieve elements and occasionally enters an adjacent companion or phloem parenchyma cell where virus replication occurs. In some plants this is followed by cell-to-cell movement into only a small cluster of adjacent cells, while in others there is no cell-to-cell movement. Different proportions of cells adjacent to sieve elements become infected in different plant species. This appears to be related to how well viral gene products interact with specific hosts. CTV has three genes that are not necessary for infection of most of its hosts, but are needed in different combinations for infection of certain citrus species. These genes apparently were acquired by the virus to extend its host range. Some specific viral gene products have been implicated in symptom induction. Remarkably, the deletion of these genes from the virus genome can induce large increases in stem pitting symptoms. The p23 gene, which is a suppressor of RNA silencing and a regulator of viral RNA synthesis, has been shown to be the cause of seedling yellows symptoms in sour orange. Most isolates of CTV in nature are populations of different strains of CTV. The next frontier of CTV biology is the understanding how the virus variants in

  1. Slight Fermentation with Lactobacillus fermentium Improves the Taste (Sugar:Acid Ratio) of Citrus (Citrus reticulata cv. chachiensis) Juice.

    Science.gov (United States)

    Yu, Yuanshan; Xiao, Gengsheng; Xu, Yujuan; Wu, Jijun; Fu, Manqin; Wen, Jing

    2015-11-01

    The aim of this study was to evaluate the hypothesis that fermentation with Lactobacillus fermentium, which can metabolize citric acid, could be applied in improving the taste (sugar:acid ratio) of citrus juice. During fermentation, the strain of L. fermentium can preferentially utilize citric acid of citrus (Citrus reticulata cv. Chachiensis) juice to support the growth without the consumption of sugar. After 6 h of fermentation with L. fermentium at 30 °C, the sugar:acid ratio of citrus juice increased to 22:1 from 12:1, which resulted in that the hedonic scores of sweetness, acidity and overall acceptability of fermented-pasteurized citrus juice were higher than the unfermented-pasteurized citrus juice. Compared with unfermented-pasteurized citrus juice, the ORAC value and total amino acid showed a reduction, and no significant change (P > 0.05) in the L*, a*, b*, total soluble phenolics and ascorbic acid (Vc) content in the fermented-pasteurized citrus juice was observed as compared with unfermented-pasteurized citrus juice. Hence, slight fermentation with L. fermentium can be used for improving the taste (sugar:acid ratio) of citrus juice with the well retaining of quality.

  2. Consumo, digestibilidade, desempenho, desenvolvimento ponderal e economicidade de dietas com polpa cítrica em substituição ao feno de capim-tifton 85 para novilhas leiteiras Effects of partial replacement of Tifton 85 hay with citrus pulp on intake, performance, and development of dairy heifers

    Directory of Open Access Journals (Sweden)

    Josué Mendes Neto

    2007-06-01

    Full Text Available Objetivou-se determinar o consumo, a digestibilidade, o desempenho, o desenvolvimento ponderal, a conversão alimentar e a economicidade de dietas com polpa cítrica em substituição ao feno de tifton 85 (Cynodon dactylon (L. Pear para novilhas leiteiras. Os tratamentos consistiram de quatro níveis (0; 16,6; 33,3 e 50% de substituição do feno por polpa cítrica. Os dados foram analisados em delineamento experimental de blocos casualizados com sete repetições. Utilizaram-se 28 novilhas holandesas (12 meses de idade e peso médio inicial de 184 kg mantidas em baias individuais. Os consumos de MS, MO, PB, CT e NDT aumentaram linearmente e o de FDN decresceu à medida que o feno foi substituído pela polpa cítrica. O consumo de EE elevou de forma quadrática com aumento dessa substituição, apresentando valor mínimo quando 2,27% do feno foi substituído pela polpa cítrica. Os consumos de Ca e P aumentaram com o aumento dos níveis de substituição do feno. Os coeficientes de digestibilidade aparente da MS, MO, PB e FDN reduziram linearmente, enquanto os de EE e CT não foram influenciados pela substituição. O ganho de peso aumentou linearmente, mas o crescimento de altura de cernelha foi menor e o de altura de garupa não foi influenciado pelos níveis de substituição. Observou-se aumento linear no perímetro torácico à medida que o feno foi substituído pela polpa cítrica. A polpa cítrica pode ser utilizada em até 35% da dieta total na alimentação de novilhas leiteiras de acordo com a conveniência econômica e a disponibilidade de alimentos volumosos, como alternativa para o produtor reduzir a idade à primeira cobertura e ao primeiro parto, com menor custo de alimentação.The objective of this trial was to evaluate intake, digestibility, performance, development, feed efficiency and feeding costs in dairy heifers fed increasing levels of citrus pulp that partially replaced Tifton-85 hay (Cynodon dactylon (L. Pear in the

  3. Influence of Plum Rootstocks on the Content of Reducing Sugars in the Annual Shoots of Cultivar ‘Kubanskaya Kometa’

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    Dēķena Dzintra

    2014-12-01

    Full Text Available The lack of suitable plum rootstocks for Baltic conditions has become a problem during recent years due to changing climatic conditions. Rapid temperature fluctuations between freezing and thawing are occurring more frequently. The winter-hardiness of rootstocks is essential for overwintering of trees in such conditions. The content of accumulated reducing sugars is an important physiological factor influencing wintering ability of trees. The dynamics of reducing sugars was investigated during two winter seasons (2010/2011 and 2011/2012 in one-year-old ‘Kubanskaya Kometa’ (Prunus x rossica Erem. hybrid plum shoots from two orchards planted in 2001 at Pūre Horticultural Research Centre (Latvia and Polli Horticultural Research Centre (Estonia. Cultivar ‘Kubanskaya Kometa’ was grafted on eight clonal rootstocks: ‘St. Julien A’, ‘Brompton’ cuttings, ‘Ackermann’, ‘Pixy’, GF8/1, G5/22, GF655/2, ‘Hamyra’ and eight seedling rootstocks: ‘St. Julien INRA 2’, ‘St. Julien d’Orleans’, ‘St. Julien Noir’, ‘Brompton’ seedlings, ‘Wangenheims Zwetsche’, ‘St. Julien Wädenswill’, ‘Myrobаlan’ and Prunus cerasifera var. divaricata. Trees were planted at 5×3 m spacing in four replications per rootstock with three trees per plot. Shoot samples were harvested five times during the winter period. The concentration of reducing sugars (mg g-1 dry weight was determined with Bertran’s method. Significant differences in concentration of reducing sugar were found between samples coming from different locations and in two seasons. The maximum concentration of reducing sugar was found in December or January depending on growing location and meteorological conditions

  4. In vitro xanthine oxidase inhibitory activity of leaves, fruits and peel extracts of Citrus aurantium, Citrus limetta and Citrus limon

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    Muthiah PL

    2012-07-01

    Full Text Available Aim of the study: To evaluate the in vitro xanthine oxidase inhibitory activity of the extract of leaves, fruits and peel of Citrus aurantium, Citrus limetta and Citrus limon.   Materials and Methods: Xanthine oxidase inhibitory activity was assayed spectrophotometrically under aerobic conditions and the degree of enzyme inhibition was determined by measuring the increase in absorbance at 295nm associated with uric acid formation.   Results: Among the extracts tested, the C.limetta peel extract exhibited highest potency of xanthine oxidase inhibition (IC50 40.16±0.88μg/ml. This was followed by C.aurantium peel (IC50 51.50±2.05μg/ml, C.limon peel (IC50 64.90±1.24μg/ml, C.aurantium leaf (IC5073.50±1.26μg/ml, C.limetta leaf (IC50 74.83±2.42μg/ml, C.limon leaf (IC50 76.83±2.02μg/ml, C.limetta fruit (IC50 95.16±0.60μg/ml extracts compared with the IC50 value of standard allopurinol was 6.6μg/ml.   Conclusion: Recent findings show that the occurrence of gout is increasing worldwide, possibly due to the changes in dietary habits like intake of food rich in nucleic acids, such as meat, sea foods, etc. Xanthine oxidase inhibitors such as allopurinol is the drug of choice, however it has been observed more side effects.  An alternative to allopurinol is the use of medicinal plants, We thus began our program to look for xanthine oxidase inhibitors of phytochemical origin. In conclusion, the study suggests that the leaves and peel extracts of Citrus aurantium, Citrus limetta and Citrus limon possess xanthine oxidase inhibitory activity that might be helpful in preventing or slowing the progress of gout and related disorders.

  5. In vitro seed germination and rootstock establishing for micrografting of Theobroma cacao L

    Science.gov (United States)

    Micrografting has been successfully implemented in several plant species of Acacia, Citrus, Eucalyptus, Havea, Malus, Olea, Opuntia, Prunus and other genera. This technique is employed for plant rejuvenation, true-to-type propagation, genetic improvement, recovery of virus-free plants, testing of po...

  6. Expression profile of oxidative and antioxidative stress enzymes based on ESTs approach of citrus

    Directory of Open Access Journals (Sweden)

    Luis Antonio Peroni

    2007-01-01

    Full Text Available Plants not only evolve but also reduce oxygen in photosynthesis. An inevitable consequence of this normal process is the production of reactive oxygen species (ROS. Plants are adequately protected by the presence of multiple antioxidative enzymes in the cytosol and also in the different cell organelles such as chloroplasts, mitochondria, and peroxisomes. Traditionally, ROS were considered to be only a toxic byproduct of aerobic metabolism. However, recently it has become apparent that plants actively produce these molecules which may control many different physiological processes such as abiotic and biotic stress response, pathogen defense and systemic signaling. The search results using the Citrus Genome Program in Brazil (CitEST for oxidative stress and the antioxidant enzyme system in Citrus Sinensis variety ‘Pera IAC’ indicated that the multiple ROS-scavenging enzymes were expressed throughout all citrus tissues. The analyses demonstrated the ubiquitous expression of metallothioneins, probably indicating a constitutive expression pattern. Oxalate oxidase has been identified as the most abundant expressed gene in developing fruits, which suggests a specific function in the ripening of citrus fruit. Moreover, infected leaves with Xylella fastidiosa and Leprosis citri showed a massive change in their ROS gene expression profile which may indicate that the suppression of ROS detoxifying mechanisms may be involved in the induction of the diseases.

  7. SELECTIVITY OF SAFLUFENACIL APPLIED SINGLY AND IN COMBINATION WITH GLYPHOSATE ON COFFEE AND CITRUS CROPS

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    CLEBSON GOMES GONÇALVES

    2016-01-01

    Full Text Available Saflufenacil is absorbed by the plant leaves and roots, thus the residual permanence of this herbicide can cause losses to the crop plants. Therefore, the objective of this study was to evaluate the selectivity of the saflufenacil herbicide, applied singly and in combination with glyphosate, on coffee and citrus plants grown in a sandy soil. Two experiments were implemented and conducted in completely randomized design with four replications. The chemical treatments consisted of three sequential applications, with directed spraying of saflufenacil at rates of 0.035, 0.07 and 0.105 kg a.i. ha - 1 , glyphosate at rate of 2.160 kg a.e. ha - 1 , the two herbicides combined at the same rates, and a control without chemical treatment. The saflufenacil applied singly and in combination with glyphosate was selective for coffee and citrus plants, which presented no visual toxicity symptoms. The sequential application of saflufenacil, singly and in combination with glyphosate did not affect the growth of coffee and citrus plants. The saflufenacil has potential for use, in combination with glyphosate on controlling many weed species in coffee and citrus areas without any interference on the development of these species.

  8. Validation of high-throughput real time polymerase chain reaction assays for simultaneous detection of invasive citrus pathogens.

    Science.gov (United States)

    Saponari, Maria; Loconsole, Giuliana; Liao, Hui-Hong; Jiang, Bo; Savino, Vito; Yokomi, Raymond K

    2013-11-01

    A number of important citrus pathogens are spread by graft propagation, arthropod vector transmission and inadvertent import and dissemination of infected plants. For these reasons, citrus disease management and clean stock programs require pathogen detection systems which are economical and sensitive to maintain a healthy industry. To this end, multiplex quantitative real-time PCR (qPCR) assays were developed allowing high-throughput and simultaneous detection of some major invasive citrus pathogens. Automated high-throughput extraction comparing several bead-based commercial extraction kits were tested and compared with tissue print and manual extraction to obtain nucleic acids from healthy and pathogen-infected citrus trees from greenhouse in planta collections and field. Total nucleic acids were used as templates for pathogen detection. Multiplex reverse transcription-qPCR (RT-qPCR) assays were developed for simultaneous detection of six targets including a virus, two viroids, a bacterium associated with huanglongbing and a citrus RNA internal control. Specifically, two one-step TaqMan-based multiplex RT-qPCR assays were developed and tested with target templates to determine sensitivity and detection efficiency. The first assay included primers and probes for 'Candidatus Liberibacter asiaticus' (CLas) and Citrus tristeza virus (CTV) broad spectrum detection and genotype differentiation (VT- and T3-like genotypes). The second assay contained primers and probes for Hop stunt viroid (HSVd), Citrus exocortis viroid (CEVd) and the mitochondrial NADH dehydrogenase (nad5) mRNA as an internal citrus host control. Primers and TaqMan probes for the viroids were designed in this work; whereas those for the other pathogens were from reports of others. Based on quantitation cycle values, automated high-throughput extraction of samples proved to be as suitable as manual extraction. The multiplex RT-qPCR assays detected both RNA and DNA pathogens in the same dilution series

  9. Métodos para identificação e controle da tristeza dos citros Methods of identification and control of tristeza disease of citrus

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    S. Moreira

    1954-01-01

    s vezes é possível o emprego de pés francos provenientes dos embriões nucelares. Nas plantações já existentes pode-se fazer a substituição total ou parcelada (individual das plantas, conforme se constate predominância de afídios muito ou pouco eficientes e de estirpes fortes ou fracas do vírus. A sub-enxertia ("inarching", a sôbre-enxertia ("topworking" e o afrancamento do enxerto são outras tantas modalidades de controle da tristeza, as quais podem ser vantajosamente empregadas em determinadas condições. Medidas de quarentena podem retardar a invasão das zonas ainda livres da tristeza, -sendo de interesse o esclarecimento do público quanto ao perigo representado pela importação de plantas ou suas partes vivas, exceto as sementes.The tristeza disease of citrus has not yet been reported from European countries nor from various other citrus growing areas of the world. Investigations on the disease have been carried out in various countries, such as Argentina, Australia, Brazil, South Africa, and United States. Knowledge obtained from these investigations enables citrus experts from areas not invaded by tristeza to recognize its presence in the orchards and to prevent disastrous losses for the industry. General decline symptoms of tristeza resemble those caused by foot rot, but root examination permits the differentiation of the two diseases. Presence of pitting symptoms in trees of West Indian limes or of grapefruits permits easy diagnosis of tristeza in the orchards. Stock-scion combinations may be tolerant or intolerant to tristeza. Thus, it be comes important to determine the rootstock in case of plants showing decline symptoms. This fact can be established by direct examination of sprouts from the rootstock or by observing the degree of congeniality of rootstock and scion. The colorimetric tests made with bark of the rootstock may help to determine it. Field observation of symptoms complemented by Schneider's histological tests may replace the

  10. Production of tetraploid plants of non apomictic citrus genotypes.

    Science.gov (United States)

    Aleza, Pablo; Juárez, José; Ollitrault, Patrick; Navarro, Luis

    2009-12-01

    Ploidy manipulation in Citrus is a major issue of current breeding programs aiming to develop triploid seedless mandarins to address consumer demands for seedless fruits. The most effective method to obtain triploid hybrids is to pollinate tetraploid non apomictic cultivars with pollen of diploid varieties. Such non apomictic tetraploid lines are not found in the citrus germplasm and need to be created. In this work we describe a new methodology based on in vitro shoot-tip grafting combined with treatment of the micro-grafted shoot-tip with colchicine and oryzalin to achieve chromosome doubling and a dechimerization procedure assisted by flow cytometry. Stable tetraploid plants of Clemenules, Fina and Marisol clementines and Moncada mandarin have been obtained directly from shoot tip grafting combined with colchicine and oryzalin treatments or after dechimerization of mixoploids plants (2x-4x). These stable tetraploid plants have been used in 4x x 2x hybridizations, to recover over 3,250 triploid hybrids in 3 years.

  11. SPATIAL DISTRIBUTION AND SEQUENTIAL SAMPLING OF Brevipalpus phoenicis IN CITRUS

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    WALTER MALDONADO JR

    Full Text Available ABSTRACT Among the pests of citrus, one of the most important is the red and black flat mite Brevipalpus phoenicis (Geijskes, which transmits the Citrus leprosis virus C (CiLV-C.When a rational pest control plan is adopted, it is important to determine the correct timing for carrying out the control plan. Making this decision demands constant follow-up of the culture through periodic sampling where knowledge about the spatial distribution of the pest is a fundamental part to improve sampling and control decisions. The objective of this work was to study the spatial distribution pattern and build a sequential sampling plan for the pest. The data used were gathered from two blocks of Valencia sweet orange on a farm in São Paulo State, Brazil, by 40 inspectors trained for the data collection. The following aggregation indices were calculated: variance/ mean ratio, Morisita index, Green’s coefficient, and k parameter of the negative binomial distribution. The data were tested for fit with Poisson and negative binomial distributions using the chi-square goodness of fit test. The sequential sampling was developed using Wald’s Sequential Probability Ratio Test and validated through simulations. We concluded that the spatial distribution of B. phoenicis is aggregated, its behavior best fitted to the negative binomial distribution and we built and validated a sequential sampling plan for control decision-making.

  12. Neurodegenerative Diseases: Might Citrus Flavonoids Play a Protective Role?

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    Santa Cirmi

    2016-09-01

    Full Text Available Neurodegenerative diseases (ND result from the gradual and progressive degeneration of the structure and function of the central nervous system or the peripheral nervous system or both. They are characterized by deterioration of neurons and/or myelin sheath, disruption of sensory information transmission and loss of movement control. There is no effective treatment for ND, and the drugs currently marketed are symptom-oriented, albeit with several side effects. Within the past decades, several natural remedies have gained attention as potential neuroprotective drugs. Moreover, an increasing number of studies have suggested that dietary intake of vegetables and fruits can prevent or delay the onset of ND. These properties are mainly due to the presence of polyphenols, an important group of phytochemicals that are abundantly present in fruits, vegetables, cereals and beverages. The main class of polyphenols is flavonoids, abundant in Citrus fruits. Our review is an overview on the scientific literature concerning the neuroprotective effects of the Citrus flavonoids in the prevention or treatment of ND. This review may be used as scientific basis for the development of nutraceuticals, food supplements or complementary and alternative drugs to maintain and improve the neurophysiological status.

  13. Penicillium digitatum metabolites on synthetic media and citrus fruits

    DEFF Research Database (Denmark)

    Ariza, M.R.; Larsen, Thomas Ostenfeld; Petersen, Bent O.

    2002-01-01

    Penicillium digitatum has been cultured on citrus fruits and yeast extract sucrose agar media (YES).Cultivation of fungal cultures on solid medium allowed the isolation of two novel tryptoquivaline-like metabolites, tryptoquialanine A (1) and tryptoquialanine B (2), also biosynthesized on citrus...... with fungal volatiles. The host-pathogen interaction in nature and the possible biological role of citrus volatiles are also discussed...

  14. Asian Citrus Psyllid RNAi Pathway – RNAi evidence

    OpenAIRE

    Taning, Clauvis N. T.; Andrade, Eduardo C. de; Hunter, Wayne B.; Christiaens, Olivier; Smagghe, Guy

    2016-01-01

    Diaphorina citri, known as the Asian citrus psyllid, is an important pest of citrus because it transmits a phloem-limited bacteria strongly implicated in huanglongbing (citrus greening disease). Emerging biotechnologies, such as RNA interference, could provide a new sustainable and environmentally friendly strategy for the management of this pest. In this study, genome and functional analysis were performed to verify whether the RNAi core genes are present in the Asian psyllid genome and if t...

  15. New Technologies and Systems for High Quality Citrus Fruit Production, Labor-saving and Orchard Construction in Mountain Areas of Japan

    Institute of Scientific and Technical Information of China (English)

    Kunihisa MORINAGA; Osamu SUMIKAWA; Osamu KAWAMOTO; Hiroyasu YOSHIKAWA; Seiji NAKAO; Masahiko SHIMAZAKI; Shin-no-suke KUSABA; Norihiro HOSHI

    2005-01-01

    Novel technologies have been necessary for improving fruit quality and productivity of citrus,labor-saving and orchard conservation on steep slope lands since aging of growers and decrease in the number of successors is remarkable in mountain areas of southwestern Japan. The purpose of this paper is to introduce new technologies for improving citrus production that have been developed in recent years. A new fruit quality control system using drip irrigation and liquid fertilization technique combined with year-round plastic mulching was developed, and it enables high quality and stable citrus fruit production. Water and/or nutrient solution is automatically supplied through drip tubes that are laid under the mulching sheets to give adequate water stress, so as to improve sugar and acid content of fruit. A new transportation system for steep sloping citrus orchards, which is a combination of the monorail system and contour narrow paths, was suggested. A small walking cultivator was developed to explain the procedure of narrow path excavation. After introducing the narrow path, working hours for fertilizer and chemical herbicide application were reduced. Disaster prevention mapping of citrus orchards on slope lands was developed based on computer-aided seepage estimation and topographic data. The mapping can show zones of both ascending flow and descending flow of underground water during heavy rains in citrus orchards. The mapping is considered to be effective for the management of orchards and prevention of erosion on slope lands.

  16. Extreme soil erosion rates in citrus slope plantations and control strategies. A literature review

    Science.gov (United States)

    Cerdà, Artemi; Ángel González Peñaloza, Félix; Pereira, Paulo; Reyes Ruiz Gallardo, José; García Orenes, Fuensanta; Burguet, María

    2013-04-01

    irrigated land, and this contributes to increase the soil losses due to the sloping terrain. Although citrus is a world wide food, and occupy a large surface little is being researched on their impact on soil erosion, land degradation and strategies to control the soil, water and nutrient losses. This paper review the research developed until now and the results show that there is a poor background on this topic. It is necessary to develop research projects to improve the knowledge on the impact of citrus plantations on soil degradation and soil erosion. Another key information from the literature review done, is that most of the research was done in two regions of China and one of the Mediterranean. Definitively, a poor understanding of a huge environmental problem that need more scientific research. Acknowledgements The research projects GL2008-02879/BTE and LEDDRA 243857 supported this research. References Bombino, G., Denisi, P., Fortugno, D., Tamburino, V., Zema, D.A., Zimbone, S.M. 2010. Land spreading of solar-dried citrus peel to control runoff and soil erosion. WIT Transactions on Ecology and the Environment, 140, 145-154. Cerdà, A., Giménez Morera, A., Burguet, M., Arcenegui, V., González Peñaloza, F.A., García-Orenes, F., Pereira, P. 2012. The impact of the farming, abandonment and agricultural intensification on loss of water and soil. The example of the northern slopes of the Serra Grossa, Eastern Spain [El impacto del cultivo, el abandono y la intensificación de la agricultura en la pérdida de agua y suelo. el ejemplo de la vertiente norte de la serra grossa en el este peninsular] Cuadernos de Investigacion Geografica, 38 (1), 75-94. Cerdà, A., Jurgensen, M.F. 2008. The influence of ants on soil and water losses from an orange orchard in eastern Spain. Journal of Applied Entomology, 132 (4), 306-314. Cerdà, A., Jurgensen, M.F. 2011. Ant mounds as a source of sediment on citrus orchard plantations in eastern Spain. A three-scale rainfall simulation

  17. Phylogenetic Analysis of Citrus tristeza virus Isolates of Wild Type Citrus in China

    Institute of Scientific and Technical Information of China (English)

    YI Long; ZHOU Chang-yong

    2014-01-01

    The genetic variation and phylogenetic relationships of Citrus tristeza virus (CTV) isolates collected from Chinese wild type citrus were analyzed by comparing the sequences of nine genomic regions (p23, p20, p13, p18, p25, p27, POL, HEL and k17) with the CTV isolates of cultivated citrus from different countries. The results showed that the divergence pattern of genomic RNA of the CTV isolates from wild type citrus was similar to that of other isolates from cultivated citrus, the 3´ proximal region was relatively conserved, and the 5´ proximal region had greater variability. The nine genomic regions of CTV isolates analyzed were found to have been under purifying selection in the evolution process. Phylogenetic analysis showed that the eleven Chinese wild CTV isolates were located at different clades and did not relfect their geographical origins, suggesting genetic diversity among the Chinese wild CTV populations. These results will aid in the understanding of molecular evolution of the Chinese CTV populations.

  18. Estimation of Fluoride Concentration of Various Citrus and Non-Citrus Fruits Commonly Consumed and Commercially Available in Mathura City

    Directory of Open Access Journals (Sweden)

    Navin Anand Ingle

    2013-01-01

    Full Text Available Background: Since fluoride is available from various sources, the total ingestion of fluoride by a person should be estimated taking into consideration the fluoride consumed from all the sources including fruits. There are very few epidemiological studies carried out associated with fluoride estimation in fruit samplesand especially in the Indian scenario Objective: To estimate and compare the fluoride concentration of different commercially available citrus and non-citrus fruits in Mathura city. Materials & Method: Fifteen different types of fruits commercially available and consumed by people ofMathura City were collected. Out of the 15 fruit samples 5 were citrus fruits and 10 were non-citrus fruits. The fluoride estimation of fruit samples was done at Central Laboratory,Lucknow. Juices of all 15 fruit samples were prepared, from each sample 10 ml of juice was measured and fluoride testing of each sample was carried out by using Orion 4 star -ion electrode analyzer. The collected data was analyzed using the statistical software program SPSS, version 17. Results: The fluoride concentration in citrus fruits ranged from 0.04ppm (Orange to 0.08 ppm (Tomato while in non-citrus fruits it ranged from 0.04ppm (chikoo to 0.18 ppm (Guava. No significant difference was observed between the mean fluoride concentration of citrus and non citrus fruits. Conclusions: Both citrus and non citrus fruits have fluorides. Guava was found to have the maximumamount of fluoridecontent (0.18 ppm among both the citrus and non citrus fruits.

  19. Small RNA profiling reveals phosphorus deficiency as a contributing factor in symptom expression for citrus huanglongbing disease.

    Science.gov (United States)

    Zhao, Hongwei; Sun, Ruobai; Albrecht, Ute; Padmanabhan, Chellappan; Wang, Airong; Coffey, Michael D; Girke, Thomas; Wang, Zonghua; Close, Timothy J; Roose, Mikeal; Yokomi, Raymond K; Folimonova, Svetlana; Vidalakis, Georgios; Rouse, Robert; Bowman, Kim D; Jin, Hailing

    2013-03-01

    Huanglongbing (HLB) is a devastating citrus disease that is associated with bacteria of the genus 'Candidatus Liberibacter' (Ca. L.). Powerful diagnostic tools and management strategies are desired to control HLB. Host small RNAs (sRNA) play a vital role in regulating host responses to pathogen infection and are used as early diagnostic markers for many human diseases, including cancers. To determine whether citrus sRNAs regulate host responses to HLB, sRNAs were profiled from Citrus sinensis 10 and 14 weeks post grafting with Ca. L. asiaticus (Las)-positive or healthy tissue. Ten new microRNAs (miRNAs), 76 conserved miRNAs, and many small interfering RNAs (siRNAs) were discovered. Several miRNAs and siRNAs were highly induced by Las infection, and can be potentially developed into early diagnosis markers of HLB. miR399, which is induced by phosphorus starvation in other plant species, was induced specifically by infection of Las but not Spiroplasma citri that causes citrus stubborn-a disease with symptoms similar to HLB. We found a 35% reduction of phosphorus in Las-positive citrus trees compared to healthy trees. Applying phosphorus oxyanion solutions to HLB-positive sweet orange trees reduced HLB symptom severity and significantly improved fruit production during a 3-year field trial in south-west Florida. Our molecular, physiological, and field data suggest that phosphorus deficiency is linked to HLB disease symptomology.

  20. The effect of rootstocks on the efficiency of a nursery of sweet cherry (Prunus avium L. trees cv. ‘Regina’

    Directory of Open Access Journals (Sweden)

    Piotr Baryła

    2014-01-01

    Full Text Available During the period 2006–2009 in Lublin, a study was conducted to determine the effect of five rootstocks: ‘Colt’, ‘F12/1’, sweet cherry (Prunus avium L., ‘GiSelA 5’, and ‘Piast’, on bud take in the cultivar ‘Regina’, the quality of budded trees and the efficiency of a sweet cherry tree nursery. The highest percentage of bud take in cherry trees cv. ‘Regina’ and the best efficiency of the sweet cherry tree nursery were obtained for the rootstocks ‘Piast’ and ‘Colt’. In two years during the three-year study period, the rootstock was found to significantly affect the efficiency of the sweet cherry tree nursery. When grafted on the rootstocks ‘Colt’ and ‘Piast’, a significantly higher percentage of trees met the requirements of the Polish Standard PN-R-67010 than on the clonal rootstock ‘GiSelA 5’. Under the tested conditions, the quality of maiden sweet cherry trees cv. ‘Regina’ grafted on the dwarfing rootstock ‘GiSelA 5’ was lowest.

  1. Novel diagnosis for citrus stubborn disease by detection of a spiroplasma citri-secreted protein.

    Science.gov (United States)

    Shi, Jinxia; Pagliaccia, Deborah; Morgan, Robyn; Qiao, Yongli; Pan, Songqin; Vidalakis, Georgios; Ma, Wenbo

    2014-02-01

    Citrus stubborn disease (CSD), first identified in California, is a widespread bacterial disease found in most arid citrus-producing regions in the United States and the Mediterranean Region. The disease is caused by Spiroplasma citri, an insect-transmitted and phloem-colonizing bacterium. CSD causes significant tree damage resulting in loss of fruit production and quality. Detection of CSD is challenging due to low and fluctuating titer and sporadic distribution of the pathogen in infected trees. In this study, we report the development of a novel diagnostic method for CSD using an S. citri-secreted protein as the detection marker. Microbial pathogens secrete a variety of proteins during infection that can potentially disperse systemically in infected plants with the vascular flow. Therefore, their distribution may not be restricted to the pathogen infection sites and could be used as a biological marker for infection. Using mass spectrometry analysis, we identified a unique secreted protein from S. citri that is highly expressed in the presence of citrus phloem extract. ScCCPP1, an antibody generated against this protein, was able to distinguish S. citri-infected citrus and periwinkle from healthy plants. In addition, the antiserum could be used to detect CSD using a simple direct tissue print assay without the need for sample processing or specialized lab equipment and may be suitable for field surveys. This study provides proof of a novel concept of using pathogen-secreted protein as a marker for diagnosis of a citrus bacterial disease and can probably be applied to other plant diseases.

  2. An embryogenic suspension cell culture system for Agrobacterium-mediated transformation of citrus.

    Science.gov (United States)

    Dutt, M; Grosser, J W

    2010-11-01

    A method for the genetic transformation of several citrus cultivars is described, including cultivars observed to be recalcitrant to conventional epicotyl-mediated transformation. Embryogenic cell suspension cultures, established from unfertilized ovules were used as target tissues for Agrobacterium-mediated transformation. Several modifications were made to the culture environment to investigate factors required for efficient transfer of the T-DNA and the subsequent regeneration of transgenic citrus plants. It was determined that co-cultivation of citrus cells and Agrobacterium in EME medium supplemented with maltose (EME-M) and 100 μM acetosyringone for 5 days at 25°C was optimum for transformation of each of the citrus cultivars. Efficient selection was obtained and escapes were prevented when the antibiotic hygromycin B was used as a selection antibiotic following transformation with an Agrobacterium strain containing hptII in the T-DNA region. Transgenic embryo regeneration and development was enhanced in medium that contained a liquid overlay consisting of a 1:2 mixture of 0.6 M BH3 and 0.15 M EME-M media. PCR and Southern blot analyses confirmed the presence of the T-DNA and the stable integration into the genome of regenerated plants, while RT-PCR demonstrated variable amounts of RNA being transcribed in different transgenic lines. This protocol can create an avenue for insertion of useful traits into any polyembryonic citrus cultivar that can be established as embryogenic cell suspension cultures, including popular specialty mandarins and seedless cultivars.

  3. Huanglongbing Resistance and Tolerance in Citrus

    OpenAIRE

    Stover, E.; McCollum, G.; Driggers, R.; Duan, Y; Shatters, Jr., R. G.; Ritenour, M.; Hall, D.G.; J. Chaparro

    2014-01-01

    Huanglongbing (HLB) is severely impacting Florida citrus. Productivity declines in many HLB-affected genotypes, often with greatly thinned canopies. Fruit size and quality are often adversely affected as the disease advances. HLB was assessed in diverse cultivars in commercial groves with high HLB-incidence. ‘Temple’ had the lowest HLB symptoms and Liberibacter (Las) titer, while ‘Murcott’ and ‘Minneola’ had the highest. The USDA Ft. Pierce, FL farm is managed to reveal genotype responses to ...

  4. The elaboration of a practical protocol for the micropropagation of several apple rootstock varieties

    Directory of Open Access Journals (Sweden)

    Doina Clapa

    2016-11-01

    Full Text Available The apple rootstock varieties ‘MM 106/4’, ‘MM 106/6’, ‘D 18’, ‘D 20’, ‘JTE-H’ and ‘MR 09/4’ were multiplied in vitro on modified Murashige and Skoog media gelled with wheat starch (MSs and supplemented with 0.7 mg/l BA, which provided intense axillary shoot proliferation. Among the genotypes we studied, MR 09/4 had the highest multiplication rate  (19.56, followed by D18 (15.36. The lowest multiplication rates were recorded in MM 106/6 (5.36 and in MM 106/4 (3.32. The use of the technique of direct ex vitro rooting and acclimatization in floating perlite provided rooting percentages of more than 90 %.

  5. Enraizamento in vitro de porta-enxertos de Prunus In vitro rooting of Prunus rootstocks

    Directory of Open Access Journals (Sweden)

    Marcelo Rogalski

    2003-08-01

    Full Text Available Na micropropagação de Prunus sp., o enraizamento tem sido considerado uma fase crítica, pois determina a sobrevivência das plantas durante a aclimatização. Dentre os fatores importantes ao enraizamento in vitro, destacam-se o genótipo e as auxinas por serem determinantes na indução e na formação de raízes. O objetivo deste trabalho foi avaliar o efeito de diferentes concentrações de IBA no enraizamento in vitro dos porta-enxertos de espécies do gênero Prunus: cultivares Capdeboscq e GF677, e seleções VP411 e VP417. Para o enraizamento in vitro, brotos com 2-3cm de comprimento foram introduzidos em meio de Lepoivre suplementado com 0,1; 0,5; 1,0 e 2,0 mg.L-1 IBA. Observou-se que o porta-enxerto 'Capdeboscq' apresentou maior taxa de enraizamento e maior número de raízes in vitro, sendo superior aos demais genótipos quanto a estas características. O nível de 1,0 mg.L-1 de IBA esteve associado à maior taxa média de enraizamento (100%, 64% e 64,0%, respectivamente para os porta-enxertos 'Capdeboscq', 'GF677' e VP411. O nível de 2,0 mg.L-1 de IBA foi superior para a seleção VP417 com taxa de 64% de enraizamento. Para os porta-enxertos 'Capdeboscq' e 'GF677', o número máximo de raízes foi de 9,6 e 5,2 raízes por broto, respectivamente, em resposta ao nível de 2,0 mg.L-1 de IBA, enquanto as seleções VP411 e VP417 apresentaram o maior número de raízes (3,6 e 3,9, respectivamente em resposta ao nível de 1,0 mg.L-1 de IBA.In Prunus sp. micropropagation of rooting is considered a critical stage, since it determines the plant survival during the acclimatization. Among important factors associated with rooting, the genotype and the auxins are considered important in the induction and formation of roots. The objective of the present work was to evaluate the effect of different IBA on the in vitro rooting of Prunus rootstocks Capdeboscq and GF677, and the selections VP411 and VP417. For the in vitro rooting stage, shoots of

  6. Effects of transient soil waterlogging and its importance for rootstock selection

    Directory of Open Access Journals (Sweden)

    Michelle Morales-Olmedo

    2015-08-01

    Full Text Available Under transient waterlogging, a number of transformations in the soil are generated associated with lack of aeration, seriously affecting the root system. Significant progress has been reported on understanding the effects of lack of oxygen on the metabolism of the roots, although few studies have examined changes in the soil. Diverging conclusions about the degree of tolerance exhibited by plants exclude the effects of hypoxia and anoxia on physical-chemical soil properties under plant experiments. This review examines the main changes occurring in soil and roots due to transient soil waterlogging conditions. Parameters such as antioxidant capacity, nutrient uptake dynamics and regeneration and distribution of the root system are relevant for selecting rootstocks tolerant to soil waterlogging.

  7. Comprehensive analysis of SAUR gene family in citrus and its transcriptional correlation with fruitlet drop from abscission zone A.

    Science.gov (United States)

    Xie, Rangjin; Dong, Cuicui; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-11-01

    Small auxin-up RNA (SAUR) gene family is large, and the members of which can be rapidly induced by auxin and encode highly unstable mRNAs. SAUR genes are involved in various developmental and physiological processes, such as leaf senescence, fruitlet abscis