WorldWideScience

Sample records for citrus grandis seedlings

  1. Sewage sludge as substrate for Tectona grandis L. seedlings production

    Directory of Open Access Journals (Sweden)

    Daniele Rodrigues Gomes

    2013-03-01

    Full Text Available The sewage sludge is a waste from sewage treatment plants, which can be used in formulations of substrates for seedling production. This study aimed to evaluate the effects of different proportions of sewage sludge, soil and commercial substrate on the growth characteristics of Tectona grandis seedlings in tubes of 120 cm³ volume capacity. The sewage sludge used came from the STP's Cachoeiro de Itapemirim / ES. The seedlings were grown in the forest nursery / CCA / UFES. The statistical design used in the experiment was completely randomized design (CRD with six treatments and five replications. The treatments constituted of sewage sludge : commercial substrate: soil (v: v: v, which corresponded to 20:70:10 (T1, 40:50:10 (T2, 60:30:10 (T3, 80 : 10:10 (T4, 90:0:10 (T5 and the control treatment with 0:90:10 (T6. All variables assessed were significant at the 5% level of probability. The control (T6 showed results statistically equal to or lower than the treatments T3 with 60% of sewage sludge concentration (T3. It follows then that the use of sewage sludge in seedling production is feasible and promising, however, used in a proper proportion.

  2. The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils of Citrus paradisi and Citrus grandis (L.) Osbeck

    Science.gov (United States)

    Ou, Ming-Chiu; Liu, Yi-Hsin; Sun, Yung-Wei; Chan, Chin-Feng

    2015-01-01

    The chemical composition and functional activities of cold-pressed and water distilled peel essential oils of Citrus paradisi (C. paradisi) and Citrus grandis (L.) Osbeck (C. grandis) were investigated in present study. Yields of cold-pressed oils were much higher than those of distilled oils. Limonene was the primary ingredient of essential oils of C. paradisi (cold 92.83%; distilled 96.06%) and C. grandis (cold 32.63%; distilled 55.74%). In addition, C. grandis oils obtained were rich in oxygenated or nitrogenated compounds which may be involved in reducing cardiovascular diseases or enhancing sleep effectiveness. The order of free radical scavenging activities of 4 citrus oils was distilled C. paradisi oil > cold-pressed C. paradisi oil > distilled C. grandis oil > cold-pressed C. grandis oil. Cold-pressed C. grandis oil exhibited the lowest activity in all antioxidative assays. The order of antimicrobial activities of 4 citrus oils was distilled C. grandis oil, cold-pressed C. paradisi oil > distilled C. paradisi oil > cold-pressed C. paradisi oil. Surprisingly, distilled C. grandis oil exhibited better antimicrobial activities than distilled C. paradisi oil, especially against Escherichia coli and Salmonella enterica subsp. The results also indicated that the antimicrobial activities of essential oils may not relate to their antioxidative activities. PMID:26681970

  3. The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils of Citrus paradisi and Citrus grandis (L. Osbeck

    Directory of Open Access Journals (Sweden)

    Ming-Chiu Ou

    2015-01-01

    Full Text Available The chemical composition and functional activities of cold-pressed and water distilled peel essential oils of Citrus paradisi (C. paradisi and Citrus grandis (L. Osbeck (C. grandis were investigated in present study. Yields of cold-pressed oils were much higher than those of distilled oils. Limonene was the primary ingredient of essential oils of C. paradisi (cold 92.83%; distilled 96.06% and C. grandis (cold 32.63%; distilled 55.74%. In addition, C. grandis oils obtained were rich in oxygenated or nitrogenated compounds which may be involved in reducing cardiovascular diseases or enhancing sleep effectiveness. The order of free radical scavenging activities of 4 citrus oils was distilled C. paradisi oil > cold-pressed C. paradisi oil > distilled C. grandis oil > cold-pressed C. grandis oil. Cold-pressed C. grandis oil exhibited the lowest activity in all antioxidative assays. The order of antimicrobial activities of 4 citrus oils was distilled C. grandis oil, cold-pressed C. paradisi oil > distilled C. paradisi oil > cold-pressed C. paradisi oil. Surprisingly, distilled C. grandis oil exhibited better antimicrobial activities than distilled C. paradisi oil, especially against Escherichia coli and Salmonella enterica subsp. The results also indicated that the antimicrobial activities of essential oils may not relate to their antioxidative activities.

  4. [Isolation and identification of Metarhizium from Citrus grandis 'tomentosa' GAP base].

    Science.gov (United States)

    Ma, Weisi; Xu, Jiang; Qiao, Haili; Chen, Jun; Li, Xiangming; Qin, Rongmin; Cheng, Huizhen

    2012-04-01

    A type of entomopathogenic fungus of soil in Citrus grandis 'tomentosa' production base was isolated and identified with morphological and molecular biological methods, including pathogenesis, spore characteristic and ITS sequence analysis were conducted. The results showed that eighteen entomopathogenic fungi strains were isolated from the Tenebrio molitor infected in the soil samples, which were identified as Metarhizium anisopliae var. anisopliae. Based on results above, we concluded that there was quantity of Metarhizium resources in this area. These provided the useful information for controlling some pests of C. grandis by using these strains of fungus.

  5. Flavonoid composition and antioxidant activities of Chinese local pummelo (Citrus grandis Osbeck.) varieties.

    Science.gov (United States)

    Xi, Wanpeng; Fang, Bo; Zhao, Qiyang; Jiao, Bining; Zhou, Zhiqin

    2014-10-15

    China is one of the most important diversity centres of the genus Citrus L. and is particularly rich in pummelo germplasm. In this study, the flavonoids in the peels and pulps of 28 Chinese local pummelos and four grapefruits were determined by optimised Ultra Performance Liquid Chromatography (UPLC), and their antioxidant capacities were evaluated using 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH), ferric reducing/antioxidant power (FRAP) and superoxide anion methods. We found that naringin was the predominant flavonoid in pummelo, while naringin and neohesperidin were the predominant flavonoids in grapefruit. The fruit peels of Citrus paradisi cvs. Rio Red and Cocktail had the highest contents of naringin (9871.69mg/kg FW) and neohesperidin (7011.15mg/kg FW), respectively. Overall, C. paradisi cvs. Cocktail, Rio Red and Changshanhuyou, Citrus grandis cvs. 28-19, Chandler, and Hongxinyou contained more flavonoids and exhibited higher antioxidant capacities and are potentially good sources of phytochemicals and natural antioxidants.

  6. 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

  7. Fertirrigation in production of seedlings of Eucalyptus grandis during winter and summer

    Directory of Open Access Journals (Sweden)

    Simone Fernandes Ciavatta

    2014-04-01

    Full Text Available Studies correlating the splitting of fertigation with the development and quality of tree seedlings in different production systems and periods of the year are fundamental to optimize inputs and minimization of the production cycle. Thus we conducted this study aimed to check the influence of the split of fertigation in the development and quality of Eucalyptus grandis seedlings in winter and summer periods. The fertilization through the irrigation system by capillarity was split on: one, two, three or six times in the week, maintaining the total amount of nutrients applied. We concluded that the most effective fertigation for the development and quality of seedlings of Eucalyptus grandis were six and one times in the week for the period of winter and summer, respectively, demonstrating the need for adequacy of fertigation managements according to the period of year.

  8. Pathogenic Interactions Between Xanthomonas axonopodis pv. citri and Cultivars of Pummelo (Citrus grandis).

    Science.gov (United States)

    Shiotani, H; Ozaki, K; Tsuyumu, S

    2000-12-01

    ABSTRACT The aggressiveness of strains of Xanthomonas axonopodis pv. citri on seven Citrus species, including Citrus sinensis (navel orange), C. paradisi (grapefruit), C. unshiu (Satsuma mandarin), C. junos (Yuzu), C. aurantifolia ('Mexican' lime), C. tachibana (Tachibana), and C. grandis (pummelo: 'Otachibana', 'Banpeiyu', and 'Anseikan'), were assessed by comparing lesion expansion and growth in planta, using a prick inoculation method. The existence of two groups distinct in aggressiveness was demonstrated on the pummelo cultivars, whereas the remaining species tested were uniformly susceptible. The two groups of strains were distinct in lesion expansion and growth in planta; however, both caused canker lesions on the 'Otachibana' pummelo. The sensitivity of the bacterial strains to phages Cp1 and Cp2 was associated with differences in aggressiveness. Namely, all the strains sensitive to Cp2 but resistant to Cp1 were aggressive to 'Otachibana', whereas all the strains sensitive to Cp1 but resistant to Cp2 were weakly aggressive. When a repetitive sequence-based polymerase chain reaction amplification was carried out by enterobacterial repetitive intergeneric consensus (ERIC) sequences (ERIC1R and ERIC2) as the primers, these two groups were also distinguishable by the presence or absence of a 1.8-kb DNA fragment among otherwise identical fragments. The 1.8-kb fragment was amplified only from the strains aggressive to C. grandis.

  9. Light intensity and type of container on producing Cassia grandis L. f. seedlings

    Directory of Open Access Journals (Sweden)

    Caio C. P. Leal

    2015-10-01

    Full Text Available ABSTRACTThis study aimed to determine the effects of the luminosity and type of container on producing Cassia grandis seedlings. Thus, in a substrate composed by topsoil + wood powder (1:1 the seedlings were grown into plastic tubets containing 0.3 dm3 of such substrate, or into plastic pots containing 1.0 dm3 of the same substrate, and subjected to 50 and 25% shading or full sunlight. The assessments were performed every two weeks by measuring plant height and stem diameter, during eight weeks period. At the end of this period, the leaf area, dry mass of shoots and roots, the ratio between height of plant/diameter of stem, and the Dickson quality index were also assessed. The experiment was carried out in a completely randomized design with treatments arranged in a 3 x 2 factorial [3 luminosity levels (50, 25% shading and full sunlight x 2 types of containers (plastic tubets and clay pots] with four replicates of 10 seedlings each. Means were compared by Tukey test at 0.05 probability level and adjustments for the non-linear regression polynomial curves for the assessed characteristics were computed in function of time. Shadings of 25 and 50% were the best alternatives to luminosity; and the tubets were the most suitable containers for production of Cassia grandis seedlings.

  10. SEEDLINGS ESTABLISHMENT OF Eucalyptus grandis MYCORRHIZATED WITH Pisolithus microcarpus (UFSC Pt 116 IN SANDY SOIL

    Directory of Open Access Journals (Sweden)

    Andréa Hentz de Mello

    2009-09-01

    Full Text Available The aim of this work was to evaluate the survival and the initial growth of mycorrhizated eucalypts with Pisolithus microcarpus (UFSC Pt 116 ectomycorrhizal fungus, after its transplant to area subject to the arenization process in São Francisco de Assis, RS. The area was divided into four blocks, each one with four treatments (fertile turf with and without mycorrhizae, Quartzarenic Neosoil with and without mycorrhizae. Each parcel was composed of 16 seedlings arranged in four lines in the spacing of 1,5 m x 1,5 m, totalizing in each block 64 seedlings. 90 days after the planting in the field, the eucaliptus seedlings produced in turf with fungus in the fertile substratum presented a survival rate of 100 %, whereas for those produced in fertile turf without fingi, the survival rate was 92 %. The seedlings produced in the Quartzarenic Neosoil with and without mycorrhizae had a survival rate varying around 98 and 89 %, respectively. The produced seedlings with turf and fungus showed significant differences in height and stem diameter. This study showed that the Eucalyptus grandis seedlings produced in substratum fertile turf and inoculated with the Pisolithus microcarpus (UFSC Pt 116 isolated may maintain good development and establishment in the field.

  11. Magnesium Alleviates Adverse Effects of Lead on Growth, Photosynthesis, and Ultrastructural Alterations of Torreya grandis Seedlings

    Science.gov (United States)

    Shen, Jie; Song, Lili; Müller, Karin; Hu, Yuanyuan; Song, Yang; Yu, Weiwu; Wang, Hailong; Wu, Jiasheng

    2016-01-01

    Magnesium (Mg2+) has been shown to reduce the physiological and biochemical stress in plants caused by heavy metals. To date our understanding of how Mg2+ ameliorates the adverse effects of heavy metals in plants is scarce. The potential effect of Mg2+ on lead (Pb2+) toxicity in plants has not yet been studied. This study was designed to clarify the mechanism of Mg2+-induced alleviation of lead (Pb2+) toxicity. Torreya grandis (T. grandis) seedlings were grown in substrate contaminated with 0, 700 and 1400 mg Pb2+ per kg-1 and with or without the addition of 1040 mg kg-1 Mg2+. Growth parameters, concentrations of Pb2+ and Mg2+ in the plants’ shoots and roots, photosynthetic pigment, gas exchange parameters, the maximum quantum efficiency (Fv/Fm), root oxidative activity, ultrastructure of chloroplasts and root growth were determined to analyze the effect of different Pb2+ concentrations on the seedlings as well as the potential ameliorating effect of Mg2+ on the Pb2+ induced toxicity. All measurements were tested by a one-way ANOVA for the effects of treatments. The growth of T. grandis seedlings cultivated in soils treated with 1400 mg kg-1 Pb2+ was significantly reduced compared with that of plants cultivated in soils treated with 0 or 700 mg kg-1 Pb2+. The addition of 1040 mg kg-1 Mg2+ improved the growth of the Pb2+-stressed seedlings, which was accompanied by increased chlorophyll content, the net photosynthetic rate and Fv/Fm, and enhanced chloroplasts development. In addition, the application of Mg2+ induced plants to accumulate five times higher concentrations of Pb2+ in the roots and to absorb and translocate four times higher concentrations of Mg2+ to the shoots than those without Mg2+ application. Furthermore, Mg2+ addition increased root growth and oxidative activity, and protected the root ultrastructure. To the best of our knowledge, our study is the first report on the mechanism of Mg2+-induced alleviation of Pb2+ toxicity. The generated results

  12. Magnesium alleviates adverse effects of lead on growth, photosynthesis and ultrastructural alterations of Torreya grandis seedlings

    Directory of Open Access Journals (Sweden)

    Jie Shen

    2016-11-01

    Full Text Available Magnesium (Mg2+ has been shown to reduce the physiological and biochemical stress in plants caused by heavy metals. To date our understanding of how Mg2+ ameliorates the adverse effects of heavy metals in plants is scarce. The potential effect of Mg2+ on lead (Pb2+ toxicity in plants has not yet been studied. This study was designed to clarify the mechanism of Mg2+-induced alleviation of lead (Pb2+ toxicity. Torreya grandis (T. grandis seedlings were grown in substrate contaminated with 0, 700 and 1400 mg Pb2+ per kg-1 and with or without the addition of 1040 mg kg-1 Mg2+. Growth parameters, concentrations of Pb2+ and Mg2+ in the plants’ shoots and roots, photosynthetic pigment, gas exchange parameters, the maximum quantum efficiency (Fv/Fm, root oxidative activity, ultrastructure of chloroplasts and root growth were determined to analyze the effect of different Pb2+ concentrations in the seedlings as well as the potential ameliorating effect of Mg2+ on the Pb2+ induced toxicity. The growth of T. grandis seedlings cultivated in soils treated with 1400 mg kg-1 Pb2+ was significantly reduced compared with that of plants cultivated in soils treated with 0 or 700 mg kg-1 Pb2+. The addition of 1040 mg kg-1 Mg2+ improved the growth of the Pb2+-stressed seedlings, which was accompanied by increased chlorophyll content, the net photosynthetic rate and Fv/Fm, and enhanced chloroplasts development. In addition, the application of Mg2+ induced plants to accumulate five times higher concentrations of Pb2+ in the roots and to absorb and translocate four times higher concentrations of Mg2+ to the shoots than those without Mg2+ application. Furthermore, Mg2+ addition increased root growth and oxidative activity, and protected the root ultrastructure. To the best of our knowledge, our study is the first report on the mechanism of Mg2+-induced alleviation of Pb2+ toxicity. The gener¬ated results may have important implications for understanding the

  13. Temperature effects on wood anatomy, wood density, photosynthesis and biomass partitioning of Eucalyptus grandis seedlings.

    Science.gov (United States)

    Thomas, D S; Montagu, K D; Conroy, J P

    2007-02-01

    Wood density, a gross measure of wood mass relative to wood volume, is important in our understanding of stem volume growth, carbon sequestration and leaf water supply. Disproportionate changes in the ratio of wood mass to volume may occur at the level of the whole stem or the individual cell. In general, there is a positive relationship between temperature and wood density of eucalypts, although this relationship has broken down in recent years with wood density decreasing as global temperatures have risen. To determine the anatomical causes of the effects of temperature on wood density, Eucalyptus grandis W. Hill ex Maiden seedlings were grown in controlled-environment cabinets at constant temperatures from 10 to 35 degrees C. The 20% increase in wood density of E. grandis seedlings grown at the higher temperatures was variously related to a 40% reduction in lumen area of xylem vessels, a 10% reduction in the lumen area of fiber cells and a 10% increase in fiber cell wall thickness. The changes in cell wall characteristics could be considered analogous to changes in carbon supply. Lumen area of fiber cells declined because of reduced fiber cell expansion and increased fiber cell wall thickening. Fiber cell wall thickness was positively related to canopy CO2 assimilation rate (Ac), which increased 26-fold because of a 24-fold increase in leaf area and a doubling in leaf CO2 assimilation rate from minima at 10 and 35 degrees C to maxima at 25 and 30 degrees C. Increased Ac increased seedling volume, biomass and wood density; but increased wood density was also related to a shift in partitioning of seedling biomass from roots to stems as temperature increased.

  14. Polyamines and transglutaminase activity are involved in compatible and self-incompatible pollination of Citrus grandis.

    Science.gov (United States)

    Gentile, Alessandra; Antognoni, Fabiana; Iorio, Rosa Anna; Distefano, Gaetano; Las Casas, Giuseppina; La Malfa, Stefano; Serafini-Fracassini, Donatella; Del Duca, Stefano

    2012-02-01

    Pollination of pummelo (Citrus grandis L. Osbeck) pistils has been studied in planta by adding compatible and self-incompatible (SI) pollen to the stigma surface. The pollen germination has been monitored inside the pistil by fluorescent microscopy showing SI altered morphologies with irregular depositions of callose in the tube walls, and heavy callose depositions in enlarged tips. The polyamine (PA) content as free, perchloric acid (PCA)-soluble and -insoluble fractions and transglutaminase (TGase) activity have been analyzed in order to deepen their possible involvement in the progamic phase of plant reproduction. The conjugated PAs in PCA-soluble fraction were definitely higher than the free and the PCA-insoluble forms, in both compatible and SI pollinated pistils. In pistils, pollination caused an early decrease of free PAs and increase of the bound forms. The SI pollination, showed highest values of PCA-soluble and -insoluble PAs with a maximum in concomitance with the pollen tube arrest. As TGase mediates some of the effects of PAs by covalently binding them to proteins, its activity, never checked before in Citrus, was examined with two different assays. In addition, the presence of glutamyl-PAs confirmed the enzyme assay data and excluded the possibility of a misinterpretation. The SI pollination caused an increase in TGase activity, whereas the compatible pollination caused its decrease. Similarly to bound PAs, the glutamyl-PAs and the enzyme activity peaked in the SI pollinated pistils in concomitance with the observed block of the pollen tube growth, suggesting an involvement of TGase in SI response.

  15. Incidence and management of white grub, Schizonycha ruficollis on seedlings of teak (Tectona grandis Linn. f.)

    Institute of Scientific and Technical Information of China (English)

    NITIN KULKARNI; KAILASH CHANDRA; PRAFULLA NARAHAR WAGH; KAILASH CHANDRA JOSHI; RAM BHAJAN SINGH

    2007-01-01

    An investigation was conducted annually from 2002 to 2005 between the second week of May and the end of September on the incidence of scarab beetle, Schizonycha ruficollis (Fabricius) in a teak (Tectona grandis L.f.) nursery at Ramdongari, Nagpur, India.The immature stages, that is white grubs of the scarab beetle damaged 14%-52% of teak seedlings in the nursery beds, whereas the adult of the species, that is scarab beetles, were recorded on three new host trees (Ziziphus xylopyra, Acacia catechu and A.leucophloea) in addition to the reported hosts such as ziziphus (Z. jujuba and Z. mauritiana). Beetles of the S. ruficollis started emerging from the nursery beds just after the pre-monsoon showers and continued for 10-18 days. While beetle of S. ruficollis defoliated tree hosts available in the surroundings, the immature stages of the beetle caused major damage by feeding on root systems of teak seedlings with symptoms of wilting and mortality in forest nursery beds. The result of chemical and biological treatments for the management of grubs of S. ruficollis in nursery beds indicated phorate 10% granular at the rate of 20 g/m2 and chlorpyriphos 20% emulsifiable concentrate at the rate of 5.0 mL/m2 to be effective. Grubs of S. ruficollis have not been recorded previously as a major pest of teak (T. grandis). This is also the first report on occurrence of S. ruficollis adults on tree hosts such as Z. xylopyra, A. catechu and A.leucophloea. White grubs being pests of economic importance and the toughest insects to manage, information given in this paper on incidence, pest status and management of Schizonycha ruficollis is of importance to researchers and forest nursery managers.

  16. Flavonoid profiles of immature and mature fruit tissues of Citrus grandis Osbeck (Dangyuja) and overall contribution to the antioxidant effect.

    Science.gov (United States)

    Yu, Eun Ae; Kim, Gon-Sup; Lee, Ji Eun; Park, Semin; Yi, Song; Lee, Soo Jung; Kim, Jae Hoon; Jin, Jong Sung; Abd El-Aty, A M; Shim, Jae-Han; Shin, Sung Chul

    2015-04-01

    Citrus fruits are a valuable functional food and their peel is used in East Asian folk medicine. In this study, the polar components of the fruit tissues of Citrus grandis Osbeck were analyzed using high-performance liquid chromatography-tandem mass spectrometry and compared with reported data. Among the 13 characterized compounds, eight flavonoids and one coumarin were identified for the first time in fruit tissues. The total amount of the identified components was the largest for the immature fruit peel, followed by mature fruit peel, mature fruit flesh, and immature fruit flesh. Naringin (2) and neohesperidin (3) were particularly rich in all samples. The antioxidant activity of the flavonoids extracted from fruit tissues increased in a dose-dependent manner. The activity of the fruit peels was significantly higher than that of the fruit flesh. Copyright © 2014 John Wiley & Sons, Ltd.

  17. A water-alcohol extract of Citrus grandis whole fruits has beneficial metabolic effects in the obese Zucker rats fed with high fat/high cholesterol diet.

    Science.gov (United States)

    Raasmaja, Atso; Lecklin, Anne; Li, Xiang Ming; Zou, Jianqiang; Zhu, Guo-Guang; Laakso, Into; Hiltunen, Raimo

    2013-06-01

    Epidemiological studies suggest that citrus fruits and compounds such as flavonoids, limonoids and pectins have health promoting effects. Our aim was to study the effects of Citrus grandis (L.) Osbeck var. tomentosa hort. fruit extract on the energy metabolism. A whole fruit powder from dry water and alcohol extracts of C. grandis containing 19% naringin flavonoid was prepared. The effects of the citrus extract were followed in the obese Zucker rats fed with the HFD. The circulatory levels of GLP-1 decreased significantly by the extract in comparison to the HFD group, whereas the decreased ghrelin levels were reversed. The levels of PYY were decreased in all HFD groups. The leptin amounts decreased but not significantly whereas insulin and amylin were unchanged. The cholesterol and glucose levels were somewhat but not systematically improved in the HFD fed rats. Further studies are needed to identify the active compounds and their mechanisms.

  18. Optimizing Culture System of Ri T-DNA Transformed Roots for Citrus grandis cv. Changshou Shatian You

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-hong; SUN Zhong-hai; TONG Rui-jian

    2006-01-01

    Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system of Ri T-DNA transformed roots for C. grandis cv. Changshou Shatian You was constructed as follows: After the ventral wounded striations on the single activation cotyledon were inoculated by A. rhizogenes A4 (logarithmic period), they were cocultured at (25 ± 2)℃ in darkness for 25-30 days; some transformed roots were generated from wounded striations of most cotyledons. The genetically transformed ratio is (83 ± 11)%. Axenic Ri T-DNA transformed roots (hairy roots) were harvested after five subcultures. Explants were activated on MT medium. The MS medium was used for subculture of transformed roots. Mass Ri T-DNA transformed roots in which the hormone was produced independently were harvested from this optimizing culture system. White, fresh Ri T-DNA transformed roots were (1.14 ± 0.07) cm long, (0.73 ± 0.04) mm wide, and the growth direction of transformed roots was negative geotropism.

  19. One-step column chromatographic extraction with gradient elution followed by automatic separation of volatiles, flavonoids and polysaccharides from Citrus grandis.

    Science.gov (United States)

    Han, Han-Bing; Li, Hui; Hao, Rui-Lin; Chen, Ya-Fei; Ni, He; Li, Hai-Hang

    2014-02-15

    Citrus grandis Tomentosa is widely used in traditional Chinese medicine and health foods. Its functional components include volatiles, flavonoids and polysaccharides which cannot be effectively extracted through traditional methods. A column chromatographic extraction with gradient elution was developed for one-step extraction of all bioactive substances from C. grandis. Dried material was loaded into a column with petroleum ether: ethanol (8:2, PE) and sequentially eluted with 2-fold PE, 3-fold ethanol: water (6:4) and 8-fold water. The elutes was separated into an ether fraction containing volatiles and an ethanol-water fraction containing flavonoids and polysaccharides. The later was separated into flavonoids and polysaccharides by 80% ethanol precipitation of polysaccharides. Through this procedure, volatiles, flavonoids and polysaccharides in C. grandis were simultaneously extracted at 98% extraction rates and simply separated at higher than 95% recovery rates. The method provides a simple and high-efficient extraction and separation of wide range bioactive substances.

  20. Physicochemical properties of Citrus grandis var. Jinyu seed and its oil%金柚柚籽及其油脂的理化性质分析

    Institute of Scientific and Technical Information of China (English)

    李咏梅; 谢婧

    2015-01-01

    Citrus grandis var. Jinyu see d oil was prepared by Soxhlet extraction method and the physicochemi-cal properties of Citrus grandis var. Jinyu seed and its oil were analyzed. The results showed that the mass of Citrus grandis var. Jinyu seed accounted for 10. 3% of the total fruit mass and its crude fat content reached 34. 6%. Citrus grandis var. Jinyu seed oil presented golden color, high transparency, good fluidity at room temperature, natural flavor and taste of shaddock. The relative density, moisture and volatile matter content, refractive index, acid value, saponification value, iodine value and peroxide value of Citrus grandis var. Jinyu seed oil were 0. 963 ± 0. 025 5, (0. 071 ± 0. 009 8)%,1. 454 ± 0. 038 1, (1. 273 ± 0. 103 1) mgKOH/g, (169. 75 ± 0. 483 0)mgKOH/g, (133. 3 ± 0. 066 7)gI/100 g and (4. 25 ± 0. 711 0)mmol/kg, respectively. The GC analysis result indicated that the content of unsaturated fatty acids in Citrus grandis var. Jinyu seed oil was 67. 6%, containing linoleic acid(39. 3%), oleic acid(24. 7%) and linolenic acid(3. 6%). The saturated fat-ty acids in Citrus grandis var. Jinyu seed oil were mainly palmitic acid(27. 6%) and stearic acid(3. 9%). Therefore, Citrus grandis var. Jinyu seed oil was suitable for being developed as edible oil.%采用索氏抽提法制备金柚柚籽油,并对金柚柚籽及其油脂进行理化性质分析。结果表明:金柚柚籽质量占全果总质量10.3%,柚籽粗脂肪含量高达34.6%。柚籽油色泽金黄、室温下流动性好、透明度高、有油脂固有气味和滋味,并具有一定柚子气味;相对密度0.963±0.0255,水分及挥发物含量(0.071±0.0098)%,折光指数1.454±0.0381,酸值(KOH)(1.273±0.1031)mg/g,碘值(I)(133.3±0.0667) g/100 g,皂化值(KOH)(169.75±0.4830)mg/g,过氧化值(4.25±0.7110)mmol/kg;气相色谱法分析结果显示,柚籽油中不饱和脂肪酸含量为67.6%,主要是亚油酸(39.3%)、油酸(24.7%)、亚麻酸(3.6%);饱

  1. TENACITY AND PERSISTENCE OF COPPER FUNGICIDES IN CITRUS SEEDLINGS UNDER SIMULATED RAINFALL

    Directory of Open Access Journals (Sweden)

    ANTONIO EDUARDO FONSECA

    2016-01-01

    Full Text Available The amount of fungicide that adheres to the leaf during spraying and the amount that remain on the leaf after weathering are the main factors that defines the amount of active residue on the leaf surface to effectively control plant pathogens. Thus, the objective of this work was to evaluate the tenacity and persistence of copper in citrus seedling leaves under simulated rainfall in Jaboticabal, State of São Paulo, Brazil. The evaluated variables were copper content, solution retention, surface tension and drop spectrum. A significant and inversely proportional linear relationship to drops <100 μm was found. The percentage of copper retained in leaves of citrus seedlings with copper fungicides of suspension concentrate (SC formulations after simulated rainfall was greater than 80%. Copper fungicides of SC formulations presented the lowest surface tension, allowing greater tenacity and persistence of copper on seedlings of citrus leaves after simulated rainfall and increased contact between the drops and leaf surface.

  2. The Analysis of MADS box Genes Expressing in the Citrus grandis Osbeck cv.%柚(Citrus grandis Osbeck cv.)MADS box基因的表达分析

    Institute of Scientific and Technical Information of China (English)

    张敬虎; 潘一山; 王少峰; 邹金美; 陈羡德; 林莹; 王玉玲; 蓝炎阳

    2015-01-01

    This paper is concerning the MADS box gene family from the fruitlet (less than 5 days) and the yang leaf of two kinds of pomelo breeding (Citrus grandis Osbeck cv.) using the De novo transcriptomics method. The fruitlet and the yang leaf from the Early Mature Dragon Pomelo (which was taken as mutant group)and the Guangxi Sweet Pomelo (which was taken as reference group)were taken as experiment materials, by RNA extraction, reverse transcription, sequencing and assembly Unigene sequences. The MADS box transcription factor family gene annotation results were retrieved from the Nr, Swiss Prot, KEGG and COG the four databases. Adopting digital gene expression label (DGE) technology, the gene transcription abundance in the sample was taken as RPKM value, that the differentially expressed genes (DEGs) were identified by comparing the different of the RPKM value between the mutant group and reference group, with the duplication≥2. There were 28 MADS box genes were annotated from the fruitlet and the yang leaf of the Early Mature Dragon Pomelo and the Guangxi Sweet Pomelo. There were 25 MADS box genes expressed in the fruitlet from the Early Mature Dragon Pomelo (FE) and the Guangxi Sweet Pomelo (FL), and sixs of them were DEGs. Meanwhile, There were 27 MADS box genes expressed in the leaf from the Early Mature Dragon Pomelo (LE) and the Guangxi Sweet Pomelo (LL), and sevens of them were DEGs. The 28 MADS box gene family was reported eighteens of them in Citrus clementina and twenties of them in Citrus sinensis, respectively, and fives of them have reported neither in Citrus clementina nor in Citrus sinensis, and have not found in the Citrus's other breeding.%以De novo转录组学方法分析柚(Citrus grandis Osbeck cv.)MADS box基因家族的基因.以特早熟龙柚(变异型)和琯溪蜜柚(参照型)嫩果(不超过5天)和新叶为材料,经过RNA提取、反转录、测序、组装得到Unigene序列. Unigene序列在 Nr、Swiss-Prot、KEGG 和 COG 四

  3. Leaf-disc grafting for the transmission of Candidatus Liberibacter asiaticus in citrus (Citrus sinensis; Rutaceae) seedlings1

    Science.gov (United States)

    Tabay Zambon, Flavia; Plant, Karen; Etxeberria, Ed

    2017-01-01

    Premise of the study: The search for resistance/tolerance to the devastating citrus huanglongbing disease (syn. HLB or citrus greening) is generating an increasing number of new plants of diverse genetic makeup. As the increasing number of new plants require more space, resources, and time, the need for faster and more efficient HLB screening tests becomes crucial. Methods and Results: The leaf-disc grafting system described here consists in replacing a disc of leaf tissue with a similar disc from an infected plant. This can be performed in young seedlings not yet big enough to endure other types of grafting. Graft success and infection rates average approximately 80%. Conclusions: We describe the successful adaptation of leaf-disc grafting as a powerful screening tool for HLB. The system requires minimal plant material and can be performed in seedlings at a very young age with increased efficiency in terms of time, space, and resources. PMID:28090406

  4. 柚(Citrus grandis Osbeck cv.)MADS box基因的表达分析

    Institute of Scientific and Technical Information of China (English)

    张敬虎[1; 潘一山[1; 王少峰[2; 邹金美[1; 陈羡德[1; 林莹[1; 王玉玲[1; 蓝炎阳[2

    2015-01-01

    以De novo转录组学方法分析柚(Citrus grandis Osbeck cv.)MADS box基因家族的基因.以特早熟龙柚(变异型)和琯溪蜜柚(参照型)嫩果(不超过5天)和新叶为材料,经过RNA提取、反转录、测序、组装得到Unigene序列.Unigene序列在Nr、Swiss-Prot、KEGG和COG四大数据库中进行比对,获得MADS box转录因子家族基因注释结果.采用数字基因表达标签(digital gene expression tag,DGE)技术,对样本中基因转录丰度以RPKM值表示,比较处理组和对照组的RPKM值,以倍性变化≥2确定差异表达基因(differentially expressed genes,DEGs).从特早熟龙柚和琯溪蜜柚嫩果和叶片中,总共注释到28个MADS box基因家族基因.在龙柚嫩果(FE)和蜜柚嫩果(FL)中表达的有25个,其中有6个属于差异表达基因.在龙柚叶片(LE)和蜜柚叶片(LL)中表达的有27个,其中有7个属于差异表达基因.注释到的28个MADS box基因家族基因在克莱门特柚(Citrus clementina)和中国甜橙(Citrus sinensis)报道过的分别有18个和20个,其中有5个基因既在中国甜橙和克莱门特柚都没有报道过,也没有发现在其它Citrus物种报道过.

  5. White grubs, Holotrichia rustica and Holotrichia mucida (Coleoptera: Scarabaeidae) as pests of teak (Tectona grandis L. f.) seedlings

    Institute of Scientific and Technical Information of China (English)

    Nitin Kulkarni; Sanjay Paunikar; Kailash Chandra Josh; John Rogers

    2009-01-01

    Field observations were carried out between 2002 and 2005 on bio-ecology of white grubs infesting teak (Tectona grandis Linn, f.) seedlings at Ramdongari Forest Nursery, Forest Development Corporation of Maharashtra, Nagpur in central India. The study collected the data required for an integrated pest management strategy against the white grubs. The species damaging teak seedlings were Holotrichia rustica (Burmeister) and H. mucida Gyllenhal. The beetles (adults) of both these species began to emerge just after the pre-monsoon showers and when the relative humidity had risen rapidly over several days, but before the first monsoon rains. While the adults fed and mated on naturally growing bushes of Ziziphus jujuba, Z. mauritiana, Z. xylopyra, Acacia leucophloea and A. catechu immediately after the emergence from the teak beds in the nursery, the immature stages (grubs) of both species fed on roots of the teak seedling, leading to plant death. This is the first report of (i) damage caused to teak seedlings by grubs of H. rustica and H. mucida, and (ii) of Z jujuba and Z mauritiana being hosts for the beetles of H. mucida and H. rustica. It is also the first detailed report on the field bio-ecology of the H. rustica and H. mucida as major pests of teak. White grubs are among the toughest-to-manage pests of economic importance and information presented here on the pest incidence and damage of H. rustica and H. mucida is important to researchers and nursery field managers for the management of these pests on teak.

  6. 神经网络技术在化橘红两品种识别中的应用%Application of Neural Network in the Discrimination of Two Different Species of Exocarpium Citrus Grandis

    Institute of Scientific and Technical Information of China (English)

    魏航; 林励; 黄志煜; 陈永刚; 袁旭江

    2011-01-01

    Objective To establish an effective model for the discrimination of Citrus grandis ' Tomentosa' and C. grandis (L.) Osbeck, which are the medicinal plant sources of Exocarpium Citrus Grandis. Methods Twentythree batches of medicinal material samples of Exocarpium Citrus Grandis were collected from different places. Fingerprints of the samples were determined by HPLC, and several variables based on principal component analysis were selected for the establishment of BP neural network model. Results An effective BP neural network model was established. The distinguishing rate was over 91.3%, and the samples of Citrus grandis ' Tomentosa' were all correctly recognized. Conclusion Neural network technology can offer a feasible approach to the effective discrimination of Citrus grandis ' Tomentosa'.%[目的]建立有效区别毛橘红与光橘红2种药材的识别模型.[方法]收集不同产地的23批化橘红药材样品的指纹图谱,采用主成分分析法提取主成分,利用BP神经网络进行模式识别.[结果]建立了有效识别毛橘红和光橘红的神经网络模型,有效识别率超过91.3%,其中毛橘红均能被正确识别.[结论]神经网络技术可有效识别出道地药材毛橘红.

  7. ORIGIN OF ORGANIC SUBSTRATES FOR PRODUCTION OF SEEDLINGS OF TEAK (Tectona grandis Linn. F.

    Directory of Open Access Journals (Sweden)

    Paulo André Trazzi

    2013-08-01

    Full Text Available http://dx.doi.org/10.5902/1980509810551The utilization of renewable waste as a source of nutrients for forest seedlings production can be a solution to environmental problems, mainly related to the disposal of these materials. In this context, this study aimed to evaluate the use of renewable substrates as substrate components in the production of teak seedlings. Seedlings were grown in tubes with a volume capacity of 280 cm³, using for the composition of treatments cattle manure, poultry litter or manure quail associated with subsoil earth and a fraction of 25% of commercial forestry substrate, and the formed substrates were subjected to chemical analysis. Ninety days after transplanting the seedlings, the following morphological characteristics were analyzed: shoot height, stem diameter, dry weight of shoots, roots and total and Dickson quality index. The results indicated that the seedlings produced with substrates formulated with poultry litter had the highest growth from the traits studied, given that the treatment with 35% of this material provided the greatest gains. The use of renewable substrates may be indicated for forest seedling production, contributing for the improvement of the chemical properties of substrates formed and consequently for the plant nutrition.

  8. Root signalling and modulation of stomatal closure in flooded citrus seedlings.

    Science.gov (United States)

    Rodríguez-Gamir, Juan; Ancillo, Gema; González-Mas, M Carmen; Primo-Millo, Eduardo; Iglesias, Domingo J; Forner-Giner, M Angeles

    2011-06-01

    In this work, we studied the sequence of responses induced by flooding in citrus plants, with the aim of identifying the signals that lead to stomatal closure. One-year-old seedlings of Carrizo citrange, grown in sand under greenhouse conditions, were waterlogged for 35 d and compared with normally watered well-drained plants. Significant decreases in stomatal conductance and transpiration were detected between flooded and control seedlings from a week after the beginning of the experiment. However ABA concentration in leaves only started to increase after three weeks of flooding, suggesting that stomata closed in the absence of a rise in foliar ABA. Therefore, stomatal closure in waterlogged seedlings does not appear to be induced by ABA, at least during the early stages of flood-stress. The low levels of ABA detected in roots and xylem sap from flooded seedlings indicated that it is very unlikely that the ABA increase in the leaves of these plants is due to ABA translocation from roots to shoots. We propose that ABA is produced in old leaves and transported to younger leaves. Flooding had no effect on water potential or the relative water content of leaves. Soil flooding reduced root hydraulic conductance in citrus seedlings. This effect was already evident after a week of waterlogging, and at the end of the experiment, flood-stressed seedlings reached values of root hydraulic conductance below 12% of that of control plants. This reduction was related to down-regulation of the expression of PIP aquaporins. In addition, whole plant transpiration was reduced by 56% after 35 d under flooding conditions. Flood-stress also decreased the pH of sap extracted from citrus roots. Evidence is presented suggesting that acidosis induced by anoxic stress in roots causes gating of aquaporins, thereby decreasing hydraulic conductance. Additionally, stomatal closure finely balances-out low pH-mediated losses of root hydraulic conductance therefore maintaining stable leaf

  9. Study on essence oils from citrus grandis peel and orange peel extracted by microwave method%微波辐射法提取柚皮、橙皮的挥发油

    Institute of Scientific and Technical Information of China (English)

    陈纯馨; 陈忻; 袁毅桦; 梁少华

    2003-01-01

    The essence oil of citrus grandis peel and orange peel was extracted by the microwave method in this article.The results show that the best condition of extracting is when 100 g peel is extracted at 360 W with n-hexane for 50 s,the obtained rate of pomelo oil is 1.73% and orange oil is 0.65%.

  10. Calcium and potassium silicates and the growth of Eucalyptus grandis seedlings Aplicação de silicatos de cálcio e de potássio e o crescimento de mudas de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Itamar Antonio Bognola

    2011-06-01

    Full Text Available

    The use of silicate is a practice that has been frequently adopted in annual crops, although few studies have been conducted in order to verify its efficiency in forest tree species. The main objective of this research was to evaluate the effect of calcium and potassium silicates in the growth of seedlings of Eucalyptus grandis. The experiment was conducted in a greenhouse, in Alambari county, State of São Paulo. A completely randomized experimental design was adopted, with eight treatments, three replications and 25 plants per plot, maintained at the field capacity moisture level. Seedlings were planted in plastic tubes using local substrate, basic fertilization and silicates. Diameter, height and fresh and dry biomass of the seedlings were determined 150 days after silicates treatments were applied. The use of silicates either in the substrate or through foliar application, in the production of eucalypt seedlings has proven to be inadequate when the substrate presents a balanced basic composition in terms of nutrients and pH.

    doi: 10.4336/2011.pfb.31.66.83

    O uso de silicato é uma prática que vem sendo adotada com frequência em culturas anuais, muito embora poucos trabalhos tenham sido realizados com intuito de verificar sua eficiência em espécies florestais arbóreas. O objetivo principal desta pesquisa foi avaliar o efeito da aplicação de silicatos de cálcio e de potássio no crescimento de mudas de Eucalyptus grandis. O experimento foi conduzido em casa de vegetação, no Município de Alambari, SP. O delineamento usado foi inteiramente ao acaso, com oito tratamentos, três repetições e 25 plantas por parcela, sendo mantidas na umidade de capacidade de campo. As mudas foram plantadas em tubetes de plástico, utilizando substrato local, com adubação básica e silicatos. Diâmetro de colo, altura e biomassa verde e seca das mudas foram determinados 150 dias após a

  11. Behavior of Eucalyptus grandis and E. cloeziana seedlings grown in arsenic-contaminated soil Comportamento de mudas de E. grandis E. eucalyptus cloeziana cultivadas em solo contaminado por arsênio

    Directory of Open Access Journals (Sweden)

    Roseli Freire Melo

    2010-06-01

    Full Text Available Arsenic has been considered the most poisonous inorganic soil pollutant to living creatures. For this reason, the interest in phytoremediation species has been increasing in the last years. Particularly for the State of Minas Gerais, where areas of former mining activities are prone to the occurrence of acid drainage, the demand is great for suitable species to be used in the revegetation and "cleaning" of As-polluted areas. This study was carried out to evaluate the potential of seedlings of Eucalyptus grandis (Hill Maiden and E. cloeziana F. Muell, for phytoremediation of As-polluted soils. Soil samples were incubated for a period of 15 days with different As (Na2HAsO4 doses (0, 50, 100, 200, and 400 mg dm-3. After 30 days of exposure the basal leaves of E. cloeziana plants exhibited purple spots with interveinal chlorosis, followed by necrosis and death of the apical bud at the 400 mg dm-3 dose. Increasing As doses in the soil reduced root and shoot dry matter, plant height and diameter in both species, although the reduction was more pronounced in E. cloeziana plants. In both species, As concentrations were highest in the root system; the highest root concentration was found in E. cloeziana plants (305.7 mg kg-1 resulting from a dose of 400 mg dm-3. The highest As accumulation was observed in E. grandis plants, which was confirmed as a species with potential for As phytoextraction, tending to accumulate As in the root system and stem.O arsênio (As tem sido considerado o poluente inorgânico de solo mais tóxico para os seres vivos, razão pela qual o interesse por espécies indicadoras e fitorremediadoras tem aumentado nos últimos anos. Particularmente para o Estado de Minas Gerais, que apresenta áreas remanescentes de atividade mineradora sujeitas à ocorrência de drenagem ácida, existe grande demanda por espécies com potencial para serem utilizadas na revegetação e "limpeza" de substratos contaminados por esse metaloide. Este

  12. 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.

  13. Residue trend of imidacloprid in fruits of Citrus grandis%吡虫啉在化橘红果中的残留动态研究

    Institute of Scientific and Technical Information of China (English)

    乔海莉; 程惠珍; 李少南; 陈君; 陈荣敏; 覃蓉敏; 徐常青; 于晶; 徐荣; 李向明

    2011-01-01

    目的:研究低毒内吸性杀虫剂吡虫啉在化橘红果实中的残留动态.方法:在化橘红采果前期,树干基部注射吡虫啉可溶性溶液,施药后定期采集化橘红果实,采用高效液相色谱法测定果实中吡虫啉的残留量.结果:以每厘米树干胸径注入0.8mL吡虫啉药剂后,化橘红果实中的农药残留量始终保持在很低的水平;以每厘米树干胸径注入1.5 mL吡虫啉药剂后,前7 d果实中的农药残留量一直在很低的水平,7 d后迅速上升,14 d时达到高峰,之后逐渐下降,30 d降至0.835 mg·kg-1,低于国内和国际上吡虫啉在柑橘类成果中最大残留限量(MRLs≤1 mg·kg-1).以施用1.5 mL·cm-1吡虫啉药剂对化橘红蛀茎害虫的防治效果最佳.结论:在化橘红果实采收期前30 d,以每厘米树干胸径注入1.5 mL吡虫啉药液,能有效地防治化橘红蛀茎害虫,且果实中的农药残留量始终在安全范围内.%Objective : To study on residue trend of imidacloprid in fruits of Citrus grandis. Methods : It was examined by high performance liquid chromatography ( HPLC) after trunk injection. Results : The residue of imidacloprid remained a low period in fruits of C. grandis after injection with 0. 8 mL · cm-1 diluted of imidacloprid. When the trunk was injected with 1. 5 mL · cm -1 diluted of imidacloprid, the residue level of imidacloprid in fruits increased on the 7th day immediately. And the peak level was detected on the 14th day after the treatment. The level of imidacloprid in fruits was 0. 835 mg · kg-1 in the 30th day, which was lower than MRLs ( 1 mg · kg-1). Conclusions:When imidacloprid through trunk injection was applied to control bore pests of C. grandis,which was diluted with 1. 5 mL · cm -1 ,the safe interval period was more than 30 d.

  14. Flooding affects uptake and distribution of carbon and nitrogen in citrus seedlings.

    Science.gov (United States)

    Martínez-Alcántara, Belén; Jover, Sara; Quiñones, Ana; Forner-Giner, María Ángeles; Rodríguez-Gamir, Juan; Legaz, Francisco; Primo-Millo, Eduardo; Iglesias, Domingo J

    2012-08-15

    Soil flooding has been widely reported to affect large areas of the world. In this work, we investigated the effect of waterlogging on citrus carbon and nitrogen pools and partitioning. Influence on their uptake and translocation was also studied through ¹⁵N and ¹³C labeling to provide insight into the physiological mechanisms underlying the responses. The data indicated that flooding severely reduced photosynthetic activity and affected growth and biomass partitioning. Total nitrogen content and concentration in the plant also progressively decreased throughout the course of the experiment. After 36 days of treatment, nitrogen content of flooded plants had decreased more than 2.3-fold compared to control seedlings, and reductions in nitrogen concentration ranged from 21 to 55% (in roots and leaves, respectively). Specific absorption rate and transport were also affected, leading to important changes in the distribution of this element inside the plant. Additionally, experiments involving labeled nitrogen revealed that ¹⁵N uptake rate and accumulation were drastically decreased at the end of the experiment (93% and 54%, respectively). ¹³CO₂ assimilation into the plant was strongly reduced by flooding, with δ¹³C reductions ranging from 22 to 37% in leaves and roots, respectively. After 36 days, the relative distribution of absorbed ¹³C was also altered. Thus, ¹³C recovery in flooded leaves increased compared to controls, whereas roots exhibited the opposite pattern. Interestingly, when carbohydrate partitioning was examined, the data revealed that sucrose concentration was augmented significantly in roots (37-56%), whereas starch was reduced. In leaves, a marked increase in sucrose was detected from the first sampling onwards (36-66%), and the same patter was observed for starch. Taken together, these results indicate that flooding altered carbon and nitrogen pools and partitioning in citrus. On one hand, reduced nitrogen concentration appears to

  15. Effects of Low pH on Photosynthesis, Related Physiological Parameters, and Nutrient Profiles of Citrus

    Science.gov (United States)

    Long, An; Zhang, Jiang; Yang, Lin-Tong; Ye, Xin; Lai, Ning-Wei; Tan, Ling-Ling; Lin, Dan; Chen, Li-Song

    2017-01-01

    Seedlings of “Xuegan” (Citrus sinensis) and “Sour pummelo” (Citrus grandis) were irrigated daily with a nutrient solution at a pH of 2.5, 3, 4, 5, or 6 for 9 months. Thereafter, the following responses were investigated: seedling growth; root, stem, and leaf concentrations of nutrient elements; leaf gas exchange, pigment concentration, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and chlorophyll a fluorescence; relative water content, total soluble protein level, H2O2 production and electrolyte leakage in roots and leaves. This was done (a) to determine how low pH affects photosynthesis, related physiological parameters, and mineral nutrient profiles; and (b) to understand the mechanisms by which low pH may cause a decrease in leaf CO2 assimilation. The pH 2.5 greatly inhibited seedling growth, and many physiological parameters were altered only at pH 2.5; pH 3 slightly inhibited seedling growth; pH 4 had almost no influence on seedling growth; and seedling growth and many physiological parameters reached their maximum at pH 5. No seedlings died at any given pH. These results demonstrate that citrus survival is insensitive to low pH. H+-toxicity may directly damage citrus roots, thus affecting the uptake of mineral nutrients and water. H+-toxicity and a decreased uptake of nutrients (i.e., nitrogen, phosphorus, potassium, calcium, and magnesium) and water were likely responsible for the low pH-induced inhibition of growth. Leaf CO2 assimilation was inhibited only at pH 2.5. The combinations of an impaired photosynthetic electron transport chain, increased production of reactive oxygen species, and decreased uptake of nutrients and water might account for the pH 2.5-induced decrease in CO2 assimilation. Mottled bleached leaves only occurred in the pH 2.5-treated C. grandis seedlings. Furthermore, the pH 2.5-induced alterations of leaf CO2 assimilation, water-use efficiency, chlorophylls, polyphasic chlorophyll a fluorescence (OJIP) transients and

  16. Effects of High Toxic Boron Concentration on Protein Profiles in Roots of Two Citrus Species Differing in Boron-Tolerance Revealed by a 2-DE Based MS Approach

    Science.gov (United States)

    Sang, Wen; Huang, Zeng-Rong; Yang, Lin-Tong; Guo, Peng; Ye, Xin; Chen, Li-Song

    2017-01-01

    Citrus are sensitive to boron (B)-toxicity. In China, B-toxicity occurs in some citrus orchards. So far, limited data are available on B-toxicity-responsive proteins in higher plants. Thirteen-week-old seedlings of “Sour pummelo” (Citrus grandis) and “Xuegan” (Citrus sinensis) was fertilized every other day until dripping with nutrient solution containing 10 μM (control) or 400 μM (B-toxicity) H3BO3 for 15 weeks. The typical B-toxic symptom only occurred in 400 μM B-treated C. grandis leaves, and that B-toxicity decreased root dry weight more in C. grandis seedlings than in C. sinensis ones, demonstrating that C. sinensis was more tolerant to B-toxicity than C. grandis. Using a 2-dimensional electrophoresis (2-DE) based MS approach, we identified 27 up- and four down-accumulated, and 28 up- and 13 down-accumulated proteins in B-toxic C. sinensis and C. grandis roots, respectively. Most of these proteins were isolated only from B-toxic C. sinensis or C. grandis roots, only nine B-toxicity-responsive proteins were shared by the two citrus species. Great differences existed in B-toxicity-induced alterations of protein profiles between C. sinensis and C. grandis roots. More proteins related to detoxification were up-accumulated in B-toxic C. grandis roots than in B-toxic C. sinensis roots to meet the increased requirement for the detoxification of the more reactive oxygen species and other toxic compounds such as aldehydes in the former. For the first time, we demonstrated that the active methyl cycle was induced and repressed in B-toxic C. sinensis and C. grandis roots, respectively, and that C. sinensis roots had a better capacity to keep cell wall and cytoskeleton integrity than C. grandis roots in response to B-toxicity, which might be responsible for the higher B-tolerance of C. sinensis. In addition, proteins involved in nucleic acid metabolism, biological regulation and signal transduction might play a role in the higher B-tolerance of C. sinensis.

  17. 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.

  18. 沙田柚无机焦磷酸酶基因的 cDNA 克隆及序列分析%Cloning and sequence analysis of inorganic pyrophosphatase gene from Citrus grandis var.shatianyu

    Institute of Scientific and Technical Information of China (English)

    秦新民; 万珊; 李惠敏; 覃屏生; 张渝

    2015-01-01

    related)and non-self(genetically unrelated)pollen.Inorganic pyrophosphatase(IPPase)play important roles in regu-lating the growth and development in plants.In order to better understand the mechanism of IPP gene in the self-in-compatibility of Citrus grandis var.shatianyu ,the inorganic pyrophosphatase gene of C .grandis var.shatianyu was cloned and physicochemical properties of pyrophosphatase were analyzed.The total RNA was isolated from style of C .grandis var.shatianyu used the total RNA Purification System(Invitrogen)and following the manufacture′s pro-tocols.According to the EST sequence(internal fragment of inorganic pyrophosphatase gene)in suppression subtrac-tive hybridization libraries of C .grandis var.shatianyu style,4 specific primers 5′-GSP1,5′-nGSP1,3′-GSP2 and 3′-nGSP2 were designed for amplifying 3-RACE and 5-RACE of the gene.The full-length sequences of cDNA of inor-ganic pyrophosphatase gene were obtained from suppression subtractive hybridization libraries of C .grandis var.shatianyu style by the SMART-RACE PCR method.A comparison of the similarity of the full-length cDNA se-quence of the inorganic pyrophosphatase gene was performed in the GenBank database used the BLAST program.DNAman software was used for mino acid sequence and homology analysis.Prediction of molecular weight, isoeletric point(pI)and hydrophobicity were performed by using on line software ExpASy and DNAman.A 150 bp band in 3-RACE,and a 900 bp band in 5-RACE were cloned by nested and non nested PCR method.For the full-length cDNA sequences,the middle sequence,3-RACE and 5-RACE sequence of the inorganic pyrophosphatase gene were spliced and formed the full-length cDNA sequences.As a result,the cDNA of inorganic pyrophosphatase was 1 136 bp in length containing an 654 bp open reading frame(ORF),which encoded a protein of 217 amino acids with a 170 bp 5 untranslated region(5 UTR)and a 321 bp 3 UTR.The sequence of the cloned cDNA of the inorganic pyro-phosphatase from C .grandis

  19. Micropropagation of Eucalyptus grandis and nitens using tissue culture techniques

    Energy Technology Data Exchange (ETDEWEB)

    Furze, M.J.; Creswell, C.F.

    1985-01-01

    Experiments with nodal explants of E. grandis and E. nitens seedlings and E. grandis coppice shoots showed that a large number of plants can be produced from a single explant using micropropagation. The percentage of micropropagated shoots that formed roots was about 90% for E. grandis and 80% for E. nitens. For both species, about 90% of the rooted shoots survived after hardening off. 9 references.

  20. Isolation and identification of Metarhizium from Citrus grandis ‘tomentosa’ GAP base%化橘红GAP基地土壤绿僵菌的分离鉴定

    Institute of Scientific and Technical Information of China (English)

    马维思; 徐江; 乔海莉; 陈君; 李向明; 覃蓉敏; 程惠珍

    2012-01-01

    A type of entomopathogenic fungus of soil in Citrus grandis 'tomentosa' production base was isolated and identified with morphological and molecular biological methods, including pathogenesis, spore characteristic and ITS sequence analysis were conducted. The results showed that eighteen entomopathogenic fungi strains were isolated from the Tenebrio molitor infected in the soil samples, which were identified as Metarhizium anhopliae var. anisopliae. Based on results above, we concluded that there was quantity of Metarhaium resources in this area. These provided the useful information for controlling some pests of C grandis by using these strains of fungus.%目的:从化橘红GAP基地土壤中分离、鉴定绿僵菌,为进一步利用绿僵菌防治化橘红害虫奠定基础.方法:采用黄粉虫诱集法从40份土壤样品中诱集、分离绿僵菌,通过形态特征和ITS序列比对鉴定其种类.结果:从化橘红GAP基地土壤中共分离出18个绿僵菌菌株,经鉴定均为金龟子绿僵菌小孢变种Metarhizium anisopliae var.anisoplia.结论:化橘红GAP基地环境适于金龟子绿僵菌小孢变种生存,土壤中拥有丰富的绿僵菌资源,这为进一步利用绿僵菌防治化橘红害虫奠定基础.

  1. 新干特早柚GPAT基因5'端克隆及序列分析%Cloning and Sequencing Analysis of the 5' Fragment of GPAT Gene from Citrus grandis cv. Xingantezaoyou

    Institute of Scientific and Technical Information of China (English)

    吴波; 刘勇

    2009-01-01

    Citrus maxima cv. Xingantezaoyou' s GPAT gene of 5' end fragment was isolated from the leaf by means of 5 ' - RACE technology. The cDNA fragment is 832 bp long ( GenBank Accession No: DQ193970). The nucleotide sequence analysis showed that these sequences of GPAT 5' end fragment are greatly different from those of other plants. The best nucleotide similarity to Citrus unshiu was 98.9% but those Carthamus tinctorius, Arabidopsis thaliana ,Elaeis guineensis, Pisum sativum and Viciafaba were 62.5% ,54.6% , 48.2% ,47.4% and 46.9% respectively. The deduce amino acids sequence analysis showed the similarity to Carthamus tinctorius,Arabidopsis thaliana, Elaeis guineensis,Pisum sativum and Capsicum annuum were 51.6% , 60% ,45.1% ,48% and 52.3%. The amino acid sequences of GPAT gene has genera specificity because the similarity of amino acid sequences to Bacillus amyloliquefaciens is only 18.9%.%采用5'-RACE技术从新干特早柚(Citrus grandis cv. Xingantezaoyou)叶片中克隆出一条长832 bp的GPAT基因5'端cDNA片段(GenBank 登录号:DQ193970).序列分析结果表明:该cDNA片段序列与其它科属植物的GPAT基因序列的同源性差异较大,除与同类植物--温州蜜柑(Citrus unshiu)的同源性高达98.9%,与红花(Carthamus tinctorius)、拟南芥(Arabidopsis thaliana)、非洲油棕榈(Elaeis guineensis)、豌豆(Pisum sativum)、蚕豆(Vicia faba)的同源性分别为62.5%、54.6%、48.2%、47.4%、46.9%;其所编码的氨基酸序列与红花、拟南芥、非洲油棕榈、豌豆、辣椒的同源性分别为51.6%、60%、45.1%、48%、52.3%,与细菌(Bacillus amyloliquefaciens)的同源性仅为18.9%,说明GPAT基因的氨基酸序列具有种属特异性.

  2. Quality assessment of essential oils of Citrus Grandis peel obtained by different extraction methods%不同方法提取的柚皮精油质量评价

    Institute of Scientific and Technical Information of China (English)

    樊荣; 曾新安; 关昕

    2012-01-01

    Essential oil of Citrus Grandis peel was obtained by steam distillation,organic solvent extraction and supercritical(carbon dioxide)extraction methods,respectively.The physical and chemical properties as well as the major functional group were compared and identified.It could be concluded from the results that the quality of the essential oil obtained by steam distillation was better than that obtained by the other two extraction methods.%利用水热法、超临界萃取法、有机溶剂萃取三种不同的方法从沙田柚皮中提取柚皮精油,比较了提取出的三种精油的理化指标、香气特征,并且对精油的主要官能团进行了鉴定。通过对柚皮精油进行综合评价,得出最佳的提取方法。结果表明用水热法提取的精油香气比较纯正,精油含量较高,而且生产成本投资较少,综合评价值最高。

  3. Insulin-Mimetic Action of Rhoifolin and Cosmosiin Isolated from Citrus grandis (L. Osbeck Leaves: Enhanced Adiponectin Secretion and Insulin Receptor Phosphorylation in 3T3-L1 Cells

    Directory of Open Access Journals (Sweden)

    Yerra Koteswara Rao

    2011-01-01

    Full Text Available Citrus grandis (L. Osbeck (red wendun leaves have been used in traditional Chinese medicine to treat several illnesses including diabetes. However, there is no scientific evidence supporting these actions and its active compounds. Two flavone glycosides, rhoifolin and cosmosiin were isolated for the first time from red wendun leaves and, identified these leaves are rich source for rhoifolin (1.1%, w/w. In differentiated 3T3-L1 adipocytes, rhoifolin and cosmosiin showed dose-dependent response in concentration range of o.oo1–5 μM and 1–20 μM, respectively, in biological studies beneficial to diabetes. Particularly, rhoifolin and cosmosiin at 0.5 and 20 μM, respectively showed nearly similar response to that 10 nM of insulin, on adiponectin secretion level. Furthermore, 5 μM of rhoifolin and 20 μM of cosmosiin showed equal potential with 10 nM of insulin to increase the phosphorylation of insulin receptor-β, in addition to their positive effect on GLUT4 translocation. These findings indicate that rhoifolin and cosmosiin from red wendun leaves may be beneficial for diabetic complications through their enhanced adiponectin secretion, tyrosine phosphorylation of insulin receptor-β and GLUT4 translocation.

  4. The pathogenicity determinant of Citrus tristeza virus causing the seedling yellows syndrome maps at the 3'-terminal region of the viral genome.

    Science.gov (United States)

    Albiach-Marti, Maria R; Robertson, Cecile; Gowda, Siddarame; Tatineni, Satyanarayana; Belliure, Belén; Garnsey, Stephen M; Folimonova, Svetlana Y; Moreno, Pedro; Dawson, William O

    2010-01-01

    Citrus tristeza virus (CTV) (genus Closterovirus, family Closteroviridae) causes some of the more important viral diseases of citrus worldwide. The ability to map disease-inducing determinants of CTV is needed to develop better diagnostic and disease control procedures. A distinctive phenotype of some isolates of CTV is the ability to induce seedling yellows (SY) in sour orange, lemon and grapefruit seedlings. In Florida, the decline isolate of CTV, T36, induces SY, whereas a widely distributed mild isolate, T30, does not. To delimit the viral sequences associated with the SY syndrome, we created a number of T36/T30 hybrids by substituting T30 sequences into different regions of the 3' half of the genome of an infectious cDNA of T36. Eleven T36/T30 hybrids replicated in Nicotiana benthamiana protoplasts. Five of these hybrids formed viable virions that were mechanically transmitted to Citrus macrophylla, a permissive host for CTV. All induced systemic infections, similar to that of the parental T36 clone. Tissues from these C. macrophylla source plants were then used to graft inoculate sour orange and grapefruit seedlings. Inoculation with three of the T30/T36 hybrid constructs induced SY symptoms identical to those of T36; however, two hybrids with T30 substitutions in the p23-3' nontranslated region (NTR) (nucleotides 18 394-19 296) failed to induce SY. Sour orange seedlings infected with a recombinant non-SY p23-3' NTR hybrid also remained symptomless when challenged with the parental virus (T36), demonstrating the potential feasibility of using engineered constructs of CTV to mitigate disease.

  5. Níveis de sombreamento na produção e desenvolvimento de mudas Eucalyptus grandis Hill ex Maiden Shading levels on production and development of Eucalyptus grandis Hill ex Maiden seedlings Los niveles de sombra en la producción de plántulas y el desarrollo de Eucalyptus grandis Hill ex Maiden

    Directory of Open Access Journals (Sweden)

    Reginaldo Fereira Santos

    2011-09-01

    Full Text Available

    El objetivo de este estudio fue evaluar la influencia de los niveles de sombra en las plántulas de Eucalyptus grandis. Las plántulas fueron sometidas a los siguientes tratamientos: 0%, 18%, 30%, 50% y 70% de atenuación de la radiación solar a través de telas de color negro. El experimento se llevó a cabo en los meses de otoño de 2009 en la en lo vivero municipal de la ciudad de Catanduvas- PR durante un período de 90 días. El diseño experimental fue bloques al azar con cinco tratamientos y cinco repeticiones. La repicage de las plántulas de la semilleira para los tubetes ocurrió treinta días después de la siembra. A los 90 días se evaluó: altura de la parte aérea de las plantas, el número de hojas por planta, el diámetro del cuello, longitud de la raíz, peso fresco y seco de la hoja y cuello de la raíz. Para todas las variables dendrométricas evaluadas el efecto de los tratamientos fue significativo. Para la altura de la parte aérea, los tratamientos de 30 y 50% de sombra fueron superiores a los demás. Ya para el diámetro del cuello y el número de hojas, el tratamiento con pleno sol presento los valores más altos (0,20 y 15,2 g de hojas, respectivamente. Para la variable masa fresca y seca de hojas, cuello y de la raíz el tratamiento con 30% de sombra fue estadísticamente superior a los demás. La atenuación del 30% de la radiación solar ha proporcionado características dendométricas superiores de las plántulas a las variables analizadas para E. grandis.

    The goal of the work was to assess the influence of shading levels on seedling production of Eucalyptus grandis. The seedlings have been subjected to treatments: 0%; 18%; 30%; 50% and 70% attenuation of solar radiation through screens of polyolefins black coloring. The experiment was performed in autumn 2009 in the city hotbed of Catanduvas – PR, during a period of 90 days. The experiment

  6. Effects of Nitrogen Forms on Foliar Photosynthesis,Nutrient Status and Nitrogen Metabolism of Torreya grandis Seedlings%氮素形态对香榧苗期光合作用、主要元素吸收及氮代谢的影响

    Institute of Scientific and Technical Information of China (English)

    唐辉; 李婷婷; 沈朝华; 胡渊渊; 吴家胜

    2014-01-01

    In this study,we measured the photosynthetic rate,the contents of primary inorganic elements,and nitrate reductase activity and leaf N content of Torreya grandis seedlings subjected to different inorganic nitrogen treatments. The results showed that the nitrogen forms and the ratio had significant impact on the photosynthetic rate,N,P,K content, and the nitrate reductase ( NR) activity of T. grandis seedlings. With the mixture of NH4 +-N and NO3 --N at the ratio of 1:1 and 3:1,the photosynthetic rate,and stomatal conductance (Gs) and transpiration rate (Tr) were significant higher compared to plants fed with sole NH4 +-N or NO3 --N. However,there were no different significances in intercellular CO2 concentration (Ci) among the different inorganic nitrogen treatments. The sole NH4 +-N and NO3 --N fed plants had lower phosphorus ( P ) and potassium ( K ) content than that treated with mixed nitrogen of NH4 +-N and NO3 --N. Plants supplied with both forms of N ( NH4 +-N /NO3 --N =25/75 and 50/50 ) had higher NO3 - content and NR activity in comparison to the plants only fed with NO3 --N. Compared to the plants fed with NH4 +-N or NO3 --N alone,significant higher N content was observed in the plants fed with mixture of NH4 +-N and NO3 --N ( NH4 +-N /NO3 --N =50/50 and 25/75). It is concluded that Torreya grandis seedlings have no obvious preference to NH4 +-N or NO3 --N. The mixture of NH4 +-N and NO3 --N at the ratio of 1∶1 is able to boost the photosynthesis,nutrients absorption and nitrogen metabolism of T. grandis seedlings.

  7. Interferência de herbicidas, associados a um análogo de brassinosteroide, no aparato fotossintético de mudas de Eucalyptus grandis Effects of herbicides, associated to a brassinosteroid Analogue, on the photosynthetic apparatus of Eucalyptus grandis seedlings

    Directory of Open Access Journals (Sweden)

    C.M.M. Silva

    2009-01-01

    Full Text Available Avaliaram-se os efeitos da aplicação dos herbicidas imazapyr e glyphosate e as suas interações com um análogo espirostânico da castasterona (BB16 no crescimento de mudas clonais de Eucalyptus grandis. Para isso, utilizou-se a aplicação de BB16 (nas concentrações de 0,08 e 0,16 mg L-1: BB16(- e BB16(+, respectivamente, de imazapyr (0,750 kg ha-1 e de glyphosate (1,440 kg ha-1. Os tratamentos foram constituídos pelo controle, BB16(-, BB16(+, glyphosate, imazapyr, além da interação hormônio-herbicida, em intervalo de 12 h entre a aplicação de BB16 e de cada herbicida, e vice-versa. A mensuração da fluorescência da clorofila a foi realizada diariamente, na terceira folha totalmente expandida, além das avaliações de altura, diâmetro e biomassa seca da parte aérea (BSPA e das raízes (BSR. O controle, BB16(- e BB16(+ diferiram dos demais tratamentos para BSPA, porém, para BSR, altura e diâmetro, não houve diferença significativa entre os tratamentos. As médias dos parâmetros de fluorescência, obtidas para os tratamentos que receberam a aplicação dos herbicidas, foram superiores ao controle, BB16(- e BB16(+ até o sétimo dia após a aplicação dos tratamentos (DAT. As mudas que receberam aplicação de glyphosate - este associado, ou não, a BB16(- ou BB16(+ - apresentaram-se necróticas antes do sétimo DAT, enquanto as que receberam imazapyr associado ao BB16 manifestaram apenas as extremidades dos ramos laterais necrosadas. Os herbicidas testados causaram efeitos deletérios no aparato fotossintético de E. grandis; todavia, a partir do sétimo DAT as mudas que receberam a aplicação de imazapyr (com ou sem BB16 não diferiram dos tratamentos controle, BB16(- e BB16(+, quanto aos parâmetros de fluorescência.The effects of the application of imazapyr and glyphosate and their interactions with a spirostanic analogue of castasterone (BB16, on the growth of seedling clones of Eucalyptus grandis were evaluated

  8. Racemization at C-2 of naringin in pummelo (Citrus grandis) with increasing maturity determined by chiral high-performance liquid chromatography.

    Science.gov (United States)

    Caccamese, Salvatore; Chillemi, Rosa

    2010-02-12

    The relative content of (2S)- and (2R)-naringin in the albedo of pummelo during maturation in the entire season was determined by normal-phase HPLC using Chiralpak IB, a polysaccharide-derived chiral stationary phase, and n-hexane/ethanol doped with 0.5% TFA as mobile phase. A sigmoid curve was obtained showing variation from 95.3% of (2S)-naringin in very immature fruits to 53% in mature fruit samples (2.3 and 14.4cm diameter, respectively). A comparison was made with previous results obtained for grapefruit and sour orange and a tentative explanation of the bitter taste of sour orange is proposed. The Chiralpak IB is much more efficient with respect to the Chiralcel OD used for the other two Citrus species and separation and resolution factors of 1.73 and 9.2, respectively, were achieved. Authentic samples of naringin and neohesperidin were also separated into their C-2 diastereomers with Chiralpak IB and isolation of the pure diastereomers of naringin was accomplished.

  9. Cloning and sequence analysis of citrate synthase and phosphoenolpyruvate carboxylase in the root of ‘Sour pummelo' (Citrus grandis)%酸柚根系CS和PEPC基因的克隆及序列分析

    Institute of Scientific and Technical Information of China (English)

    杨林通; 林郑和; 陈立松

    2012-01-01

    Total RNA was extracted from root of ' sour pummelo' ( Citnus grandis) by hot borate method. The sequence of conserved region, 3' RACE product and 5' RACE product of citrate synthase (CS) and phosphoenolpyruvate cariboxylase (PEPC) genes were obtained by RT-PCR and RACE. The full-length cDNA of CS was 1217 bp, which contained a 1413 bp open reading frame (ORF) encoding 472 amino acids with a calculated molecular mass of 52.487 ku and an isoelectric point of 6.9, a 67 bp 5'-untranslated region (UTR) and a277 bp 3'-UTR. An alignment of deduced amino acid sequence of CS gene from ' sour pummelo' with other plants showed ihey shared high homeology (85.4% -99.6%). The full-length cDNA of PEPC was 3307, which contained a 2604 bp ORF encoding 868 amino acids with a calculated molecular mass of 99.569 ku and an isoelectric point of 6.68, a 431 bp 5'-UTR and a 269 bp 3'-UTR. An alignment of deduced amino acid sequence of PEPC gene from sour pummelo with other plants showed they shared high homeology (85.8% -95.7%).%以酸柚(Citrus grandis)根系为材料,利用热硼酸法提取了根系总RNA,并逆转录成cDNA,利用PCR和RACE技术相继得到柠檬酸合酶基因(CS)和磷酸烯醇式丙酮酸羧化酶基因(PEPC)的保守区、3′端和5′端.酸柚根系CS基因全长1760bp,开放读码框有1413bp,编码472个氨基酸,氨基酸序列相对分子质量为52.487 ku,等电点为6.9,亲水指数为-0.199;5′端非编码区为67 bp,3′端非编码区为277 bp;推导的氨基酸经序列比对,发现与其他物种具有很高的同源性(85.4% -99.6%).酸柚根系PEPC基因全长3307bp,开放读码框有2604 bp,编码868个氨基酸,氨基酸序列相对分子质量为99.569ku,等电点为6.68,亲水指数为-0,398;5′端非编码区为431 bp,3′端非编码区为269 bp,推导的氨基酸经序列比对,发现与其他物种具有很高的同源性(85.8% - 95.7%).初步确定克隆到的为酸柚根系CS和PEPC基因,登

  10. 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.

  11. 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.

  12. Expressing p20 hairpin RNA of Citrus tristeza virus confers Citrus aurantium with tolerance/resistance against stem pitting and seedling yellow CTV strains

    Institute of Scientific and Technical Information of China (English)

    CHENG Chun-zhen[1,2,5; YANG Jia-wei[3; YAN Hu-bin[4; BEI Xue-jun[1,2; ZHANG Yong-yan[1,2; LU Zhi-ming[1; ZHONG Guang-yan[2,5

    2015-01-01

    The Citrus tristeza virus (CTV) uses 3 silencing suppressor genes, p20, p23 and p25, to resist the attacks from its Citrus hosts. Inactivating these genes is therefore obviously a potential defensive option in addition to the current control strat- egies including aphid management and the use of mild strain cross protection. In this study, we cloned partial DNA frag- ments from the three genes, and used them to construct vectors for expressing hairpin RNAs (hpRNAs). To facilitate the formation of hpRNAs, the constructs were introduced in a loop structure. Following transformation of sour orange (Citrus aurantium) with these constructs, 8 p20 hpRNA (hp20) and 1 p25 hpRNA (hp25) expressing lines were obtained. The 7 hp20 transgenic lines were further characterized. Their reactions to CTV were tested following inoculation with CT14A and/ or TR-L5"I4, both of which are severe strains. Results showed that 3 lines (hp20-5, hp20-6 and hp20-8) were completely resistant to TR-L514 under greenhouse conditions for no detectable viral load was found in their leaves by PCR. However, they exhibited only partial suppression of TR-L514 under screen house conditions since the virus was detected in their leaves, though 2 months later compared to non-transgenic controls. Further tests showed that hp20-5 was tolerant also to CT14A under screen house conditions. The growth of hp20-5 was much better than others including the controls that were concurrently challenged with CT14A. These results showed that expressing p20 hpRNAwas sufficient to confer sour orange with CTV resistance/tolerance.

  13. Expressing p20 hairpin RNA of Citrus tristeza virus confers Citrus aurantium with tolerance/resistance against stem pitting and seedling yellow CTV strains

    Institute of Scientific and Technical Information of China (English)

    CHENG Chun-zhen; YANG Jia-wei; YAN Hu-bin; BEI Xue-jun; ZHANG Yong-yan; LU Zhi-ming; ZHONG Guang-yan

    2015-01-01

    The Citrus tristeza virus (CTV) uses 3 silencing suppressor genes, p20, p23 and p25, to resist the attacks from its Citrus hosts. Inactivating these genes is therefore obviously a potential defensive option in addition to the current control strat-egies including aphid management and the use of mild strain cross protection. In this study, we cloned partial DNA frag-ments from the three genes, and used them to construct vectors for expressing hairpin RNAs (hpRNAs). To facilitate the formation of hpRNAs, the constructs were introduced in a loop structure. Fol owing transformation of sour orange (Citrus aurantium) with these constructs, 8 p20 hpRNA (hp20) and 1 p25 hpRNA (hp25) expressing lines were obtained. The 7 hp20 transgenic lines were further characterized. Their reactions to CTV were tested fol owing inoculation with CT14A and/or TR-L514, both of which are severe strains. Results showed that 3 lines (hp20-5, hp20-6 and hp20-8) were completely resistant to TR-L514 under greenhouse conditions for no detectable viral load was found in their leaves by PCR. However, they exhibited only partial suppression of TR-L514 under screen house conditions since the virus was detected in their leaves, though 2 months later compared to non-transgenic controls. Further tests showed that hp20-5 was tolerant also to CT14A under screen house conditions. The growth of hp20-5 was much better than others including the controls that were concurrently chal enged with CT14A. These results showed that expressing p20 hpRNA was sufifcient to confer sour orange with CTV resistance/tolerance.

  14. 1-Aminocyclopropane-1-Carboxylic Acid Transported from Roots to Shoots Promotes Leaf Abscission in Cleopatra Mandarin (Citrus reshni Hort. ex Tan.) Seedlings Rehydrated after Water Stress.

    Science.gov (United States)

    Tudela, D; Primo-Millo, E

    1992-09-01

    The effect of water stress and subsequent rehydration on 1-aminocyclopropane-1-carboxylic acid (ACC) content, ACC synthase activity, ethylene production, and leaf abscission was studied in Cleopatra mandarin (Citrus reshni Hort. ex Tan.) seedlings. Leaf abscission occurred when drought-stressed plants were allowed to rehydrate, whereas no abscission was observed in plants under water stress conditions. In roots of water-stressed plants, a high ACC accumulation and an increase in ACC synthase activity were observed. Neither increase in ACC content nor significant ethylene production were detected in leaves of water-stressed plants. After rehydration, a sharp rise in ACC content and ethylene production was observed in leaves of water-stressed plants. Content of ACC in xylem fluid was 10-fold higher in plants rehydrated for 2 h after water stress than in nonstressed plants. Leaf abscission induced by rehydration after drought stress was inhibited when roots or shoots were treated before water stress with aminooxyacetic acid (AOA, inhibitor of ACC synthase) or cobalt ion (inhibitor of ethylene-forming enzyme), respectively. However, AOA treatments to shoots did not suppress leaf abscission. The data indicate that water stress promotes ACC synthesis in roots of Cleopatra mandarin seedlings. Rehydration of plants results in ACC transport to the shoots, where it is oxidized to ethylene. Subsequently, this ethylene induces leaf abscission.

  15. Optimization design based on kinetic model and extraction process of pectin from pomelo (Citrus grandis L.Osbeck) fruit peel%柚果皮果胶浸提过程及动力学分析优化设计

    Institute of Scientific and Technical Information of China (English)

    周存山; 余筱洁; 马海乐; 王允祥; 韩平

    2013-01-01

    以琯溪蜜柚果皮为原料,采用果胶酸解浸提法,基于果胶在浸提过程中包括原果胶转变为果胶、果胶从组织扩散到溶剂、果胶大分子降解等进程,以同步串联反应法构建果胶浸提动力学模型,获得基于浸提工艺优化和果胶同步降解影响的浸提动力学方程,进而进行模型验证分析及参数优化.有效性(残差分析及F检验)检验表明:该模型可应用于分析柚果皮果胶浸提动力学过程,在温度70 ~ 90℃,浸提过程表观活化能Ea为31.34kJ· mol-1;优化分析获得在浸提液pH =2.0,浸提温度90℃,浸提时间90.25 min,料液质量与体积比为1:40时,柚果皮果胶浸提得率11.83%,此结果与正交设计优化结果吻合.%The pectin extraction of pomelo (Citrus grandis L. Osbeck) fruit peel was investigated by the method of acid hydrolysis. The kinetic model of the processes of protopectin hydrolysis to pectin, pectin diffusion from tissue to solvent, degradation of some pectin macromolecules was established by synchronous series reaction method to estimate the most important mass transfer coefficients. Based on the effects of degradation and extraction of pectin, and optimization of simultaneous extraction conditions, the kinetic equations were obtained to realize model validation and optimization parameter. The validations of residual error analysis and F test show that the model can be applied to the kinetic analysis of pectin extraction from pomelo fruit peel. The apparent activation energy of extraction process is 31. 34 kJ·mol-1 at temperature of 70 - 90 ℃ . According to the optimization analysis, the pectin extraction yield from pomelo fruit peel is 11. 83% of dried peel at the optimized conditions with pH value of 2. 0,extraction temperature of 90 ℃ , extraction time of 90 min and solid to liquid ration of 1 : 40. The optimization condition and the maximum yield from kinetic model are confirmed by the results from orthogonal experiment.

  16. Morphological and Physiological Characteristics of Eucalyptus urophylla ×E. grandis (DH32-29) Seedlings Under Different Cadmium Concentrations%镉胁迫对尾巨桉幼苗生长和生理特性的影响

    Institute of Scientific and Technical Information of China (English)

    刘国粹; 杜阿朋; 李慧; 王志超; 张利丽; 竹万宽; 陈少雄

    2015-01-01

    Cadmium is one of the most common heavy metals causing soil contamination problems. Bioremediation is an effective way to rehabilitate soils contaminated with this comp. An pot trial was conducted to measure various morphological and physiological indices of Eucalyptus urophylla × E. grandis (DH32-29) grown under treatments of eight different soil concentrations of Cadmium (Cd) ranging from 10 to 140 mg·kg-1. There were no significant differences found among seedling grown at low concentration (10 mg·kg-1) of Cd and the control (i.e. no Cadmium). Under higher Cd concentrations (>20 mg·kg-1) seedling growth was significantly impacted. As Cd concentration increases, the biomass, chlorophyll content, fluorescent parameter (PSⅡ), maximum photochemical quantum yield (Fv/Fm), efficiency of PS Ⅱ photochemistry (φPS Ⅱ ), non-photochemical quenching coefficient (Np) and nitrogen balance index (NBI) decreased, photochemical quenching (qP) showed little change, whilst malondialdehyde (MDA) increased. Seedlings of clone DH32-29 show clear visible symptoms of injury at levels above 20 mg·kg-1 and at plant growth stagnated at Cd concentration exceeding 40 mg·kg-1. It was concluded that DH32-29 seedlings can grow normally at lower Cadmium concentrations (≤20 mg·kg-1). But as the concentration increases, above this level, the morphological and physiological characteristics of seedlings start to display significant impacts. Surveys of soil Cadmium levels in areas suited to Eucalyptus plantations and related research results in combination with this current study illustrate the potential soil remediation value of DH32-29 for areas where soils are affected by Cd pollution.%以尾巨桉(DH32-29)幼苗为试验材料,以植株的生长指标(苗高、地径、叶面积)、生物量、根冠比、氮平衡指数(NBI)、叶绿素相对含量(SPAD 值)、丙二醛(MDA)含量和叶绿素荧光参数为指标,通过盆栽试验设置8个10~140 mg·kg-1浓度镉(Cd)盐

  17. 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

  18. Effects of endophytic fungus in eucalyptus on the cold resistance of the seedling of E. urophylla × E. grandis%桉树内生菌对尾巨桉幼苗抗寒性的影响

    Institute of Scientific and Technical Information of China (English)

    谢安强; 洪伟; 吴承祯; 封磊; 林晗; 李键; 范海兰

    2011-01-01

    Ten kinds of endophytic fungus in eucalyptus were inoculated in the seedling of E. urophylla ×E. grandis by applying fungus liquid, the experiment of low temperature stress was carried thirty days later. The results showed that in comparison with control group the semilethal temperature of treatment group 1,7,5,6,9,3,2 and 8 decreased by 2.71,2.28, 1.98, 0.77, 0.61, 0.61,0.26 and 0.08 ℃, respectively; the activities of POD of treatment group 1,7,10,5,8,2,6,4 increased by 35.40%, 22.52%, 12.11%,12.11% ,10.04%, 8.23%, 4.04% and 0.62%, respectively; the activities of SOD of treatment group 1,3,4,5,7 and 8 increased by 36.39%, 6.79%, 0.06%, 4.97%, 12.98% and 8.25% respectively; the content of MDA of treatment 5,7,1,4 and 9 decreased by 40.40%, 29.08%, 28.86%, 4.88% and 1.78%, respectively. The results indicated that the cold resistance of eucalyptus increased greatly by inoculating with No. 1 endophytic fungus of eucalyptus.%采用菌液浇施方法对尾巨桉幼苗接种10株桉树内生菌,接种30d后进行低温胁迫.结果表明,处理1、7、5、6、9、3、2、8的半致死温度分别比对照下降了2.71、2.28、1.98、0.77、0.61、0.61、0.26、0.08℃.植株在低温条件下,处理1、7、10、5、8、2、6、4的POD活性分别比对照提高了35.40%、22.52%、12.11%、12.11%、10.04%、8.23%、4.04%和0.62%;处理1、3、4、5、7、8的SOD活性分别比对照提高了36.39%、6.79%0.06%、4.97%、12.98%和8.25%;处理5、7、1、4、9的MDA含量分别比对照下降了40.40%、29.08%、28.86%、4.88%和1.78%.表明菌种1可提高桉树的抗寒能力.

  19. Effects of boron deficiency on major metabolites, key enzymes and gas exchange in leaves and roots of Citrus sinensis seedlings.

    Science.gov (United States)

    Lu, Yi-Bin; Yang, Lin-Tong; Li, Yan; Xu, Jing; Liao, Tian-Tai; Chen, Yan-Bin; Chen, Li-Song

    2014-06-01

    Boron (B) deficiency is a widespread problem in many crops, including Citrus. The effects of B-deficiency on gas exchange, carbohydrates, organic acids, amino acids, total soluble proteins and phenolics, and the activities of key enzymes involved in organic acid and amino acid metabolism in 'Xuegan' [Citrus sinensis (L.) Osbeck] leaves and roots were investigated. Boron-deficient leaves displayed excessive accumulation of nonstructural carbohydrates and much lower CO2 assimilation, demonstrating feedback inhibition of photosynthesis. Dark respiration, concentrations of most organic acids [i.e., malate, citrate, oxaloacetate (OAA), pyruvate and phosphoenolpyruvate] and activities of enzymes [i.e., phosphoenolpyruvate carboxylase (PEPC), NAD-malate dehydrogenase, NAD-malic enzyme (NAD-ME), NADP-ME, pyruvate kinase (PK), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS), aconitase (ACO), NADP-isocitrate dehydrogenase (NADP-IDH) and hexokinase] involved in glycolysis, the tricarboxylic acid (TCA) cycle and the anapleurotic reaction were higher in B-deficient leaves than in controls. Also, total free amino acid (TFAA) concentration and related enzyme [i.e., NADH-dependent glutamate 2-oxoglutarate aminotransferase (NADH-GOGAT) and glutamate OAA transaminase (GOT)] activities were enhanced in B-deficient leaves. By contrast, respiration, concentrations of nonstructural carbohydrates and three organic acids (malate, citrate and pyruvate), and activities of most enzymes [i.e., PEPC, NADP-ME, PK, PEPP, CS, ACO, NAD-isocitrate dehydrogenase, NADP-IDH and hexokinase] involved in glycolysis, the TCA cycle and the anapleurotic reaction, as well as concentration of TFAA and activities of related enzymes (i.e., nitrate reductase, NADH-GOGAT, glutamate pyruvate transaminase and glutamine synthetase) were lower in B-deficient roots than in controls. Interestingly, leaf and root concentration of total phenolics increased, whereas that of total soluble protein decreased

  20. Níveis de sombreamento na produção e desenvolvimento de mudas Eucalyptus grandis Hill ex Maiden Shading levels on production and development of Eucalyptus grandis Hill ex Maiden seedlings Los niveles de sombra en la producción de plántulas y el desarrollo de Eucalyptus grandis Hill ex Maiden

    OpenAIRE

    Reginaldo Fereira Santos; Leandro Morais; Augustinho Borsoi; Deonir Secco; Gláucia Cristina Moreira

    2011-01-01

    El objetivo de este estudio fue evaluar la influencia de los niveles de sombra en las plántulas de Eucalyptus grandis. Las plántulas fueron sometidas a los siguientes tratamientos: 0%, 18%, 30%, 50% y 70% de atenuación de la radiación solar a través de telas de color negro. El experimento se llevó a cabo en los meses de otoño de 2009 en la en lo vivero municipal de la ciudad de Catanduvas- PR durante un período de 90 días. El diseño experimental f...

  1. Culture in vitro and Plant Regeneration from Roots of Citrus paradisi Macf.Seedlings%葡萄柚(Citrus paradisi Macf.)实生苗根段的离体培养及植株再生研究

    Institute of Scientific and Technical Information of China (English)

    陶燕蓝; 蓝增全; 吴田

    2014-01-01

    Objective]The objective of the study was to establish regeneration system of C.para-disi in vitro and to provide useful references for the application of genetic transformation tech-nique.[Method]The roots of aseptic seedlings germinated from the seeds of 10 grapefruit varie-ties were cultured in vitro to obtain regeneration plants in the medium with different hormones and concentrations.[Results]The callus were observed in the medium MS+0.5 mg/L 6-BA+0.5 mg/L NAA and Perlist had the highest callus induction frequency (87.95%).The differentia-tion of adventitious buds was observed in the medium MS+2.0 mg/L 6-BA+0.5 mg/L NAA and Star Ruby had the largest differentiation rate of adventitious buds (37.84%).The regeneration buds were multiplied in the medium MS+2.0 mg/L 6-BA+0.2 mg/L NAA.The adventitious roots were induced in the medium 1/2 MS +1.0 mg/L IBA and the regeneration plants finally were obtained.The survival rates of regenerative plant ranged from 75.47% to 88.40%.[Con-clusion]The regeneration systems of 6 grapefruit varieties were established based on the study.%【目的】建立葡萄柚(Citrus paradisi Macf.)离体再生体系,为后续遗传转化体系的建立奠定基础。【方法】以10个葡萄柚品种种子萌发的无菌苗根段为材料,在附加不同植物激素种类及浓度的培养基上进行离体培养,并获得再生植株。【结果】在 MS+0.5 mg/L 6-BA+0.5 mg/L NAA 培养基上培养可以诱导出愈伤组织,其中“帕利斯”的诱导率最高,达87.95%;在培养基 MS+2.0 mg/L 6-BA+0.5 mg/L NAA 可分化出丛生芽,其中“星路比”分化率最高为37.84%;分化出的丛生芽在 MS+2.0 mg/L 6-BA+0.2 mg/L NAA 培养基上可以进行增殖培养;在1/2 MS+1.0 mg/L IBA 上可诱导出不定根,形成完整再生植株。炼苗移栽成活率均可达75.47%~88.40%。【结论】通过对10个葡萄柚品种根段

  2. Essential Oils from the Malaysian Citrus (Rutaceae) Medicinal Plants

    OpenAIRE

    Siti Nur Atiqah Md Othman; Muhammad Aizam Hassan; Lutfun Nahar; Norazah Basar; Shajarahtunnur Jamil; Sarker,Satyajit D.

    2016-01-01

    This review article appraises the extraction methods, compositions, and bioactivities of the essential oils from the Citrus species (family: Rutaceae) endemic to Malaysia including C. aurantifolia, C. grandis, C. hystrix, and C. microcarpa. Generally, the fresh peels and leaves of the Citrus species were extracted using different methods such as steam and water distillation, Likens-Nikerson extraction, solvent extraction, and headspace solid-phase micro-extraction (HS-SPME). Most of the Citru...

  3. (TECTONA GRANDIS LEAF POWDER

    Directory of Open Access Journals (Sweden)

    Yash Mishra

    2015-01-01

    Full Text Available In this study, the adsorption potential of Teak (Tectona grandis leaf powder (TLP toremove Methylene blue (MB and Malachite Green (MG dye molecules from aqueoussolution was investigated. Batch experiments were conducted to evaluate the influenceof operational parameters such as, pH (2−9, adsorbent dosage (1−7 g/L, contact time(15−150 minutes and initial dye concentration (20−120 mg/L at stirring speed of 150rpm for the adsorption of MB and MG on TLP. Maximum removal efficiency of 98.4%and 95.1% was achieved for MB and MG dye, respectively. The experimentalequilibrium data were analysed using Langmuir, Freundlich and Temkin isothermmodels and it was found that, it fitted well to the Freundlich isotherm model. Thesurface structure and morphology of the adsorbent was characterized using scanningelectron microscopy (SEM and the presence of functional groups and its interactionwith the dye molecules were analysed using Fourier transform infrared spectroscopy(FTIR. Based on the investigation, it has been demonstrated that the teak leaf powderhas good potential for effective adsorption of methylene blue and malachite green dye.

  4. Essential Oils from the Malaysian Citrus (Rutaceae Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Siti Nur Atiqah Md Othman

    2016-06-01

    Full Text Available This review article appraises the extraction methods, compositions, and bioactivities of the essential oils from the Citrus species (family: Rutaceae endemic to Malaysia including C. aurantifolia, C. grandis, C. hystrix, and C. microcarpa. Generally, the fresh peels and leaves of the Citrus species were extracted using different methods such as steam and water distillation, Likens-Nikerson extraction, solvent extraction, and headspace solid-phase micro-extraction (HS-SPME. Most of the Citrus oils were found to be rich in monoterpene hydrocarbons with limonene (1 as the major component identified in the peels of C. aurantifolia (39.3%, C. grandis (81.6%–96.9%, and C. microcarpa (94.0%, while sabinene (19 was the major component in the peels of C. hystrix (36.4%–48.5%. In addition, citronellal (20 (61.7%–72.5%, linalool (18 (56.5%, and hedycaryol (23 (19.0% were identified as the major components in the oil of C. hystrix leaves, C. grandis blossom and C. microcarpa leaves, respectively. The C. hystrix essential oil has been experimentally shown to have antimicrobial and antifeedant activities, while no bioactivity study has been reported on the essential oils of other Malaysian Citrus species.

  5. Aluminum-induced decrease in CO{sub 2} assimilation in citrus seedlings is accompanied by decreased activities of key enzymes involved in CO{sub 2} assimilation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L-S.; Liu, X-H. [Fujian Agriculture and Forestry University, College of Horticulture, Fuzhou (China); Qi, Y-P. [Fujian Provincial Institute of Medical Sciences, Fuzhou (China); Smith, B. R. [Cornell University, Dept. of Horticulture, Ithaca, NY (United States)

    2005-03-01

    Many previous studies provided evidence that heavy metals affect the carbon dioxide assimilation of plants by inhibiting different enzymes involved in the Calvin cycle. Other studies have shown little or no change in the activities of Calvion cycle enzymes accompanying a heavy metal-induced decline in carbon dioxide assimilation. This study reexamined aluminium toxicity in leaf carbohydrate metabolism by determining responses in citrus leaves to aluminium, specifically in terms of carbon dioxide assimilation, key enzymes in the Calvin cycle, starch and sucrose syntheses, non-structural carbohydrates, and photosynthetic intermediates. Based on results in each of these areas, it was concluded that aluminium decreases carbon dioxide assimilation, but in so doing either increases or has no effect on the activities of enzymes involved in the Calvin cycle. The decrease in carbon dioxide assimilation induced by aluminium is suspected to be the result of increased photorespiration. 41 refs., 5 tabs., 2 figs.

  6. EFFECT OF ARBUSCULAR MYCORRHIZA FUNGI INOCULATION ON TEAK (Tectona grandis Linn. F AT CIKAMPEK, WEST JAVA

    Directory of Open Access Journals (Sweden)

    Ragil S.B. Irianto

    2005-07-01

    Full Text Available The aim of this study was to identify the effect of Arbuscular Mycorhiza Fungi (AMF on the early growth of teak (Tectona grandis Linn. F plantation. Teak seedlings were inoculated with Glomus aggregatum or Mycofer (mixing of four Arbuscular Mycorrhiza Fungi (AMF : G. margarita, G. manihotis, G. etunicatum and Acalospora spinosa at the time of transplantation. At  three months old the seedlings were planted in Cikampek experimental forest. Results showed that application of G. aggregatum or mycofer to teak could accelerate height and diameter growth by up to 61%and4 7%, respectively, after three months in the field.

  7. The genome of Eucalyptus grandis

    Energy Technology Data Exchange (ETDEWEB)

    Myburg, Alexander A.; Grattapaglia, Dario; Tuskan, Gerald A.; Hellsten, Uffe; Hayes, Richard D.; Grimwood, Jane; Jenkins, Jerry; Lindquist, Erika; Tice, Hope; Bauer, Diane; Goodstein, David M.; Dubchak, Inna; Poliakov, Alexandre; Mizrachi, Eshchar; Kullan, Anand R. K.; Hussey, Steven G.; Pinard, Desre; van der Merwe, Karen; Singh, Pooja; van Jaarsveld, Ida; Silva-Junior, Orzenil B.; Togawa, Roberto C.; Pappas, Marilia R.; Faria, Danielle A.; Sansaloni, Carolina P.; Petroli, Cesar D.; Yang, Xiaohan; Ranjan, Priya; Tschaplinski, Timothy J.; Ye, Chu-Yu; Li, Ting; Sterck, Lieven; Vanneste, Kevin; Murat, Florent; Soler, Marçal; Clemente, Hélène San; Saidi, Naijib; Cassan-Wang, Hua; Dunand, Christophe; Hefer, Charles A.; Bornberg-Bauer, Erich; Kersting, Anna R.; Vining, Kelly; Amarasinghe, Vindhya; Ranik, Martin; Naithani, Sushma; Elser, Justin; Boyd, Alexander E.; Liston, Aaron; Spatafora, Joseph W.; Dharmwardhana, Palitha; Raja, Rajani; Sullivan, Christopher; Romanel, Elisson; Alves-Ferreira, Marcio; Külheim, Carsten; Foley, William; Carocha, Victor; Paiva, Jorge; Kudrna, David; Brommonschenkel, Sergio H.; Pasquali, Giancarlo; Byrne, Margaret; Rigault, Philippe; Tibbits, Josquin; Spokevicius, Antanas; Jones, Rebecca C.; Steane, Dorothy A.; Vaillancourt, René E.; Potts, Brad M.; Joubert, Fourie; Barry, Kerrie; Pappas, Georgios J.; Strauss, Steven H.; Jaiswal, Pankaj; Grima-Pettenati, Jacqueline; Salse, Jérôme; Van de Peer, Yves; Rokhsar, Daniel S.; Schmutz, Jeremy

    2014-06-11

    Eucalypts are the world s most widely planted hardwood trees. Their broad adaptability, rich species diversity, fast growth and superior multipurpose wood, have made them a global renewable resource of fiber and energy that mitigates human pressures on natural forests. We sequenced and assembled >94% of the 640 Mbp genome of Eucalyptus grandis into its 11 chromosomes. A set of 36,376 protein coding genes were predicted revealing that 34% occur in tandem duplications, the largest proportion found thus far in any plant genome. Eucalypts also show the highest diversity of genes for plant specialized metabolism that act as chemical defence against biotic agents and provide unique pharmaceutical oils. Resequencing of a set of inbred tree genomes revealed regions of strongly conserved heterozygosity, likely hotspots of inbreeding depression. The resequenced genome of the sister species E. globulus underscored the high inter-specific genome colinearity despite substantial genome size variation in the genus. The genome of E. grandis is the first reference for the early diverging Rosid order Myrtales and is placed here basal to the Eurosids. This resource expands knowledge on the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology.

  8. Effects of aluminum on the Growth of Young Citrus Seedlings%铝胁迫对柑橘实生幼苗生长的影响

    Institute of Scientific and Technical Information of China (English)

    江寰新; 陈立松; 韩霜; 张丽芬; 林剑秋

    2009-01-01

    旨在鉴定和比较12个柑橘种类品种的耐铝性,每天用含0、0.2、0.6mmol/L、1.0mmol/L和1.6mmol/LalCI3.6H:O的1/4 Hoagland营养液浇沙培茶枝柑(Citrus reticulata)、芦柑(C. reticulata)、福橘(C.reticulata)、四川红橘(C.reticulata)、文旦柚(C. grand~s)、尤力克柠檬(C. limon)、雪柑(C. sinensis)、酸橙(C.Ⅱurantium)(来自湖北)、枸头橙(C. aurantium)(来自浙江)、红木黎檬(C. limonia)、枳壳(Poncirus trifoliata)和枳柚(P.tnfoliata×C. grand/s)等12个柑橘种类品种实生幼苗3个月.雪柑、茶枝柑、芦柑、福橘、四川红橘、尤力克柠檬和枳的耐铝性较强,即使在最高铝浓度(1.6mmol/L)处理下,其根系、地上部和单株干重均与对照无显著差异;枸头橙、酸橙、红木黎檬和枳柚的耐铝性较差,在最高铝浓度(1.6mmol/L)处理时.其根系和/或地上部的生长均会受到不同程度的抑制;文旦柚耐铝性最差,最低铝浓度(0.2mmol/L)处理时.其根系和单株生长量就显著下降.铝胁迫引起茶枝柑、福橘、四川红橘、酸橙和枳实生苗根冠比增加.但对芦柑、枸头橙、尤力克柠檬、红木黎檬、文旦柚和枳柚实生苗根冠比无显著影响;除最低铝处理时雪柑根冠比降低外,其它处理之间无显著差异.雪柑、茶枝柑、芦柑、福橘、四川红橘、尤力克柠檬和枳的耐铅陛较强.枸头橙、酸橙、红禾黎檬和枳柚的耐铝性较差,文旦柚耐铝性最差.

  9. Primeiro registro de Oligonychus yothersi (McGregor (Acari: Tetranychidae em Eucalyptus grandis Hill ex Maiden no Brasil First record of Oligonychus yothersi (McGregor (Acari: Tetranychidae on Eucalyptus grandis Hill ex Maiden in Brazil

    Directory of Open Access Journals (Sweden)

    Fabrício Fagundes Pereira

    2005-08-01

    Full Text Available Relata-se a infestação de um ácaro-vermelho em mudas clonais de Eucalyptus grandis Hill ex Maiden, mantidas em casa de vegetação no município de Martinho Campos, Minas Gerais. O ácaro foi observado na parte superior das folhas que exibiam sinais de sucção de seiva e bronzeamento. Essas injúrias causaram desenvolvimento anormal e morte de plantas. O ácaro foi identificado como Oligonychus yothersi (McGregor (Acari: Tetranychidae, e isso representa o primeiro registro dessa espécie em mudas clonais de E. grandis no Brasil.An infestation of the red spider mite was reported in clone seedlings of Eucalyptus grandis Hill ex Maiden under greenhouse conditions, in the municipality of Martinho Campos, Minas Gerais State. The spider mite was found on the leaf upper faces with signs of sap suction and bronzing. Such injuries caused abnormal development and plant death. The spider mite was identified as Oligonychus yothersi (McGregor (Acari: Tetranychidae. This is the first record of O. yothersi on E. grandis seedlings in Brazil.

  10. PRODUÇÃO DE MUDAS DE Eucalyptus grandis EM SUBSTRATOS ORGÂNICOS ALTERNATIVOS

    Directory of Open Access Journals (Sweden)

    Rodrigo Ferreira da Silva

    2014-01-01

    Full Text Available Studies regarding the disposal of urban and agro-industries waste have become essential for the possibility of their use in forest seedling production and the environmental impact that would be caused by improper disposal. The study was developed to evaluate the growth of Eucalyptus grandis seedlings submitted to different types and combinations of urban and agro-industrial organic substrates. The experiment was conducted in a greenhouse in a completely randomized design with 10 treatments consisting of different substrates and proportions combinations of them (100% organic compost urban waste (COLU, 100% organic compost of the agro-industrial residue (CORA; 100% commercial substrate; 25% (COLU+ 75% Commercial; 25% CORA +75% Commercial; 25% COLU + 75% soil; 50% COLU +50% Commercial; 50% CORA +50% Commercial; 50% Commercial + 50% soiland 100% Soil and 12 repetitions. It was evaluated plant height, stem diameter, number of leaves, length between node, fresh weight of shoot and root dry mass of shoots and roots, total dry weight, main root length, root system length, root volume, average root radius, specific surface area of the root system and stability of clod.The substrates containing organic compost urban show great potential for use as alternative substrates for the production of seedlings of Eucalyptus grandis. A mixture of commercial substrate to organic compost allows the urban growth of root and the shoot of seedlings of Eucalyptus grandis. A mixture of 50% commercial substrate and 50% organic compound of agro-industrial waste provide more stem diameter growth compared to treatments containing soil or over the organic compound of agro-industrial waste.

  11. FCH_Crenichthys_baileyi grandis_19850927

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Hiko White River springfish (Crenichthys baileyi grandis) occur. "Nevada, Lincoln County. Each of...

  12. Evaluation of Tectona grandis (Linn. and Gmelina arborea (Roxb. for Phytoremediation in Crude Oil Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Oghenerioborue Mary Agbogidi

    2007-06-01

    Full Text Available A study on the effectiveness of Tectona grandis and Gmelina arborea as forest species for the phyto- remediation of crude oil contaminated soils showed that both plants responded differently to the crude oil effects. Although the plant height, number of leaves, leaf area, plant girth and the dry biomass of the test plants were significantly P≥0.05 affected at higher levels of oil treatments 10% and 15%, the 1% and 5% levels of contamination did not significantly P≤0.05 differ from the seedlings planted in the uncontaminated soils. T. grandis and G. arborea as shown in this study could be good species for phyto- remediation of crude oil contaminated habitats due to oil exploration and exploitation especially at low concentrations.

  13. Callogenesis in stem explants of Eucalyptus grandis (Hill ex Maiden showing resilience in oxide calluses

    Directory of Open Access Journals (Sweden)

    Regina Paula Willemen Pereira

    Full Text Available Callogenesis was achieved using growth regulators at different concentrations to obtain the best characteristics regarding the calluses texture aspect with the main objective to produce friable calluses from stem explants of Eucalyptus grandis. Stem segments of approximately 1 cm were excised from 30-day seedlings. The treatments were prepared based on the MS medium added with TDZ alone or combined with AIA; 2,4-D; ANA. Each treatment consisted of five repetitions with five explants per plate. After 210 days of in vitro culture, the calluses were evaluated visually and by manipulation for texture. The explants that did not produce calluses were those exposed to treatments with 2,4-D 50.0 µM; TDZ 3.0 µM and in absence of a growth regulator (control.The best protocols for maintenance of friable calluses of stem explants of Eucalyptus grandis under the conditions performed in this work were those using only TDZ.

  14. Multiplicação in vitro de Eucalyptus grandis sob estímulo com benzilaminopurina In vitro multiplication of Eucalyptus grandis under BAP pulse

    Directory of Open Access Journals (Sweden)

    Wirifran Fernandes de Andrade

    2006-12-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos do estímulo com benzilaminopurina (BAP na multiplicação in vitro de Eucalyptus grandis. Foram avaliadas as interações entre concentrações de BAP (0, 200, 400 e 600 mg L-1, tempo de exposição (1, 2 e 3 horas, pH (3 e 5,8 da solução e alterações morfológicas dos explantes. Semanalmente, foi determinada a massa da matéria fresca dos explantes. Aos 21 dias de cultura, foram avaliados: o número de brotações por tratamento, o número de brotações obtidas por explante (taxa de multiplicação, e foi realizado o resgate das plântulas para avaliação histológica. O pH não apresentou interação com os demais fatores estudados. Os tratamentos com BAP a 200 mg L-1, durante 1 e 2 horas, apresentaram-se como os mais indicados na multiplicação do E. grandis. Houve intensificação da divisão celular, no parênquima cortical e no procâmbio, representada pelo surgimento de meristemóides, em resposta aos tratamentos com 200 mg L-1 de BAP, durante 1 e 2 horas. O estímulo com BAP na multiplicação in vitro de E. grandis é viável.The objective of this work was to evaluate the effect of pulse on in vitro multiplication of Eucalyptus grandis. Interactions were evaluated among BAP concentrations (0, 200, 400 and 600 mg L-1, exposure time (1, 2 and 3 hours, pH values (3 and 5.8, and explant morphological changes. Fresh weight of the explants was determined weekly. At 21 days of culture, valuations were made of the number of shootings per treatment, number of shootings obtained per explant (multiplication rate, and seedlings rescue was accomplished for histological analysis. The pH values did not present any interaction with the other factors. The most significant treatments on E. grandis shoot multiplications were 200 mg L-1 of 6-BAP during 1 and 2 hours. There was an intensification of cell division in the cortical parenchyma and procambium, represented by the arising of meristems in

  15. 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.

  16. Analysis of Major Carotenoid Composition and Its Content of Citrus Fruit

    Institute of Scientific and Technical Information of China (English)

    TAO Jun; ZHANG Shang-long; ZHANG Liang-cheng; XU Jian-guo; LIU Chun-rong

    2003-01-01

    a-carotene, β-carotene, lycopene, β-cryptoxanthin, zeaxanthin and lutein content of fruits in53 citrus cultivars were determined using HPLC. In both peel and pulp of citrus fruit, the major carotenoidswere lutein, zeaxanthin and β-cryptoxanthin. β-carotene content was relatively low and extremely low was theamount of or-carotene. Among the 53 cultivars tested, lycopene was detected only in pulp of Cara Cara navelorange. Carotenoid content in both peel and pulp of citrus fruit was the highest in Citrus reticulata Blanco andlowest in Citrus grandis Osbeck. Consequently, as far as the health protection value is considered, fruit ofCitrus reticulata Blanco ranks probably higher than other citrus fruits. In fruit of most Citrus retieulatavarities, β-cryptoxanthin was the main carotenoid component in pulp and its amount approximated that of lu-tein in peel. Content of lutein, zeaxanthin and β-cryptoxanthin in peel was about 2.5 - 15 times that in pulp onthe basis of fresh weight. Thus peel was inferred to be the principal location for the carotenoid stock in citrus fruit.

  17. Broad sprectrum potential of Isaria fumosorosea on insect pests of citrus

    Science.gov (United States)

    Use of entomopathogenic fungi, Isaria fumosorosea, Ifr, =Paecilomyces fumosoroseus, successfully increased insect pest mortality. Spraying the Ifr containing product, PFR97 TM, on citrus seedlings was used to screen efficacy for the management of Asian citrus psyllid, Diaphorina citri; glassy-winge...

  18. 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...

  19. 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.

  20. A comparative assessment on regeneration status of indigenous woody plants in Eucalyptus grandis plantation and adjacent natural forest

    Institute of Scientific and Technical Information of China (English)

    Shiferaw Alem; Tadesse Woldemariam

    2009-01-01

    Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m× 20 m for each, were established in both of E. Grandis plantation and adjacent natural forest, independently. In each plot, species name, abundance, diameter and height were recorded. Numbers of seedling were collected in five sub-plots (4 m2) within each major plot. A total of 46 species in the plantation, and 52 species in the natural forest, which belongs to 36 families were recorded. The diversity of species (H') is 2.19 in the plantation and 2.74 in the natural forest. The density of understory woody plant was 3842 stems/ha in the plantation and 4122 stems/ha in the natural forest. The densities of seedlings in the natural forest and the plantation were 8101 stems/ha and 4151 stems/ha, respectively. High similarity of woody species composition was found between the natural forest and the plantation. The E. Grandis plantation was found favoring the regeneration and growth of Millitia ferruginia and Coffea arabica in a much better way than other underneath woody species.

  1. Comparative carotenoid compositions during maturation and their antioxidative capacities of three citrus varieties.

    Science.gov (United States)

    Yoo, Kyung-Mi; Moon, BoKyung

    2016-04-01

    This study investigated total carotenoid content, comparative carotenoid composition, vitamin C content, and total antioxidant capacity of three citrus varieties which are Yuza (Citrus junos Sieb ex Tabaka), Kjool (Citrus unshiu Marcow), and Dangyooja (Citrus grandis Osbeck). Seven carotenoids were identified, with β-cryptoxanthin, astaxanthin, and zeaxanthin being predominant in citrus varieties. Ripening increased the total carotenoid in three citrus varieties. Individual carotenoid of canthaxanthin, astaxanthin, and α-carotene in citrus varieties decreased with maturation, whereas the others increased with ripening. Yuza exhibited the highest total antioxidant capacity in 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, with VCEAC values of 582.9 mg/100 g and 451.5 mg/100g, respectively. The relative VCEAC values were vitamin C (1.00)>lycopene (0.375), α-carotene (0.304), β-carotene (0.289), β-cryptoxanthin (0.242), and zeaxanthin (0.099). These results indicate that Yuza contains higher amounts of total carotenoids, individual carotenoids, and vitamin C than other Korean citrus varieties.

  2. Strade, ferrovie e grandi rischi

    Directory of Open Access Journals (Sweden)

    Scira Menoni

    2009-07-01

    Full Text Available Nell’articolo il rapporto tra sistemi di accessibilità (ferroviaria e stradale e grandi rischi viene affrontato da due diverse prospettive. La prima vede tali sistemi come esposti e vulnerabili a diverse forme di pericolosità naturale; la seconda li considera invece quali potenziali fonti di pericolo, indagando in particolare il trasporto di sostanze pericolose. Per quanto riguarda la prima parte dell’articolo, ovvero l’analisi di vulnerabilità delle infrastrutture di trasporto a diversi agenti naturali, verranno esplicitati i fattori di vulnerabilità fisica, sistemica e organizzativa. A sostegno della modellazione proposta, si fa riferimento sia alla letteratura internazionale sia al metodo sviluppato presso il Politecnico di Milano, nei suoi ultimi sviluppi. Interessa infatti presentare un metodo relativamente semplice da utilizzare a scala vasta per poi scendere nel dettaglio necessario laddove le priorità individuata a grande scala ne indichino la necessità. Tra i fattori di vulnerabilità fisica si indicheranno gli elementi maggiormente critici per diversi tipi di sollecitazione (sismica, vulcanica, alluvionale, etc.; per quanto attiene ai fattori di vulnerabilità sistemica si considerano le interdipendenze tra reti e sistemi (inclusi gli altri servizi a rete; per quanto attiene alla vulnerabilità organizzativa si indicheranno le difficoltà nel produrre un sistema integrato di allertamento, che consenta ad esempio di chiudere tratti di strada quando questi vengano segnalati come imminentemente interessati da un dato evento estremo. Infine si indicheranno i danni che il sistema di accessibilità può subire e le ripercussioni di questi sul territorio di interesse. Nella seconda parte viene trattato un particolare tipo di trasporto, quello delle sostanze pericolose, differenziando opportunamente tra ferroviario e stradale. Il ribaltamento del punto di vista comporta la necessità di identificare in modo puntuale i fattori di

  3. I Grandi Eventi: il caso spagnolo

    OpenAIRE

    2008-01-01

    Il tema dell’articolo verte sulle trasformazioni urbane e territoriali generate dai grandi eventi in Spagna in relazione all’implementazione/trasformazione dei sistemi di trasporto durante gli stessi. A tale scopo l’articolo analizza i risultati, sia finali che attesi, delle trasformazioni degli ultimi 15 anni in Spagna in occasione di questi eventi straordinari. Nello specifico si analizzano cinque casi-studio: Barcellona ed i Giochi Olimpici del 1992, Siviglia e l’Es...

  4. Boron impregnation treatment of Eucalyptus grandis wood.

    Science.gov (United States)

    Dhamodaran, T K; Gnanaharan, R

    2007-08-01

    Eucalyptus grandis is suitable for small timber purposes, but its wood is reported to be non-durable and difficult to treat. Boron compounds being diffusible, and the vacuum-pressure impregnation (VPI) method being more suitable for industrial-scale treatment, the possibility of boron impregnation of partially dry to green timber was investigated using a 6% boric acid equivalent (BAE) solution of boric acid and borax in the ratio 1:1.5 under different treatment schedules. It was found that E. grandis wood, even in green condition, could be pressure treated to desired chemical dry salt retention (DSR) and penetration levels using 6% BAE solution. Up to a thickness of 50mm, in order to achieve a DSR of 5 kg/m(3) boron compounds, the desired DSR level as per the Indian Standard for perishable timbers for indoor use, it was found that neither the moisture content of wood nor the treatment schedule posed any problem as far as the treatability of E. grandis wood was concerned.

  5. In vivo Induction of Tetraploid in Tangerine Citrus Plants (Citrus reticulata Blanco) with the Use of Colchicine.

    Science.gov (United States)

    Surson, Suntaree; Sitthaphanit, Suphasit; Wongma, Nattapong

    2015-01-01

    This in vivo experiment was carried out at Sakhon Nakhon Rajabhat University, Sakhon Nakhon Province, Thailand during March-October 2013. The study aims to search for some possibilities in inducing a large number of tetraploid sets of chromosomes in tangerine citrus seedlings with the use of colchicine chemical. A Randomized Complete Block Design (RCBD) with four replications was used. Seeds of tangerine citrus were treated with colchicine solutions. The experiment consisted of seven treatments, i.e., T1 with 0.0% colchicine (control), T2 with 0.2% colchicine solution and submerged for 12 h, T3 with 0.2% colchicine solution and submerged for 24 h, T4 with 0.4% colchicine solution and submerged for 12 h, T5 with 0.4% colchicine solution and submerged for 24 h, T6 with 0.8% colchicine solution and submerged for 12 h, T7 with 0.8% colchicine solution and submerged for 24 h. The experiment was conducted for 91 days. The results showed that colchicine compound severely and significantly affected germination of tangerine citrus seeds. Colchicine of 0.2% in the solution with seeds submerged for 24 h gave the highest percentages of tetraploid chromosomes in seedlings of tangerine citrus (63.64%). Colchicine significantly affected seed germination, plant height, stomata density and leaf index of the tangerine citrus seeds and seedlings. Colchicine had no significant effect on poly-embryos, mono-embryos, leaf number, leaf area, leaf weight, leaf length and stomata length of the tangerine citrus seedlings.

  6. 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.

  7. ESTABELECIMENTO A CAMPO DE MUDAS DE Eucalyptus grandis MICORRIZADAS COM Pisolithus microcarpus (UFSC Pt 116 EM SOLO ARENOSO

    Directory of Open Access Journals (Sweden)

    Andréa Hentz de Mello

    2009-01-01

    Full Text Available The aim of this work was to evaluate the survival and the initial growth of mycorrhizated eucalypts with Pisolithus microcarpus (UFSC Pt 116 ectomycorrhizal fungus, after its transplant to area subject to the arenization process in São Francisco de Assis, RS. The area was divided into four blocks, each one with four treatments (fertile turf with and without mycorrhizae, Quartzarenic Neosoil with and without mycorrhizae. Each parcel was composed of 16 seedlings arranged in four lines in the spacing of 1,5 m x 1,5 m, totalizing in each block 64 seedlings. 90 days after the planting in the field, the eucaliptus seedlings produced in turf with fungus in the fertile substratum presented a survival rate of 100 %, whereas for those produced in fertile turf without fingi, the survival rate was 92 %. The seedlings produced in the Quartzarenic Neosoil with and without mycorrhizae had a survival rate varying around 98 and 89 %, respectively. The produced seedlings with turf and fungus showed significant differences in height and stem diameter. This study showed that the Eucalyptus grandis seedlings produced in substratum fertile turf and inoculated with the Pisolithus microcarpus (UFSC Pt 116 isolated may maintain good development and establishment in the field.

  8. Caracterização fisiológica da redução de crescimento de mudas de citros micorrizadas em altas doses de fósforo Physiological characterization of growth depression in arbuscular mycorrhizal citrus seedlings under high P levels

    Directory of Open Access Journals (Sweden)

    J. O. A. Sena

    2004-10-01

    Full Text Available Com o objetivo de estudar a redução de crescimento de mudas de citros micorrizadas, instalou-se um experimento em casa de vegetação com seis doses de P (0, 50, 100, 150, 200 e 250 mg kg-1, sem e com inoculação do Fungo Micorrízico Arbuscular (FMA Glomus intraradices. Como porta-enxerto, usou-se tangerineira ' Cleópatra' (Citrus reshni. O substrato usado foi uma mistura de amostra de terra (Neossolo e areia, na proporção de 3:1, com baixa concentração de P disponível. O delineamento estatístico foi inteiramente casualizado, disposto em um fatorial 6 x 2, com cinco repetições. Seis meses após o transplantio, as plantas foram avaliadas por meio das seguintes variáveis: altura de plantas, matéria seca da parte aérea, transpiração, resistência estomática e área foliar. Nas doses mais altas de P, as plantas micorrizadas apresentaram redução na altura, na matéria seca da parte aérea e na área foliar, menor taxa de transpiração e maior resistência estomática, quando comparadas com o controle não micorrizado. Considerando estes resultados, a redução no crescimento de mudas micorrizadas em alta dose de P pode estar relacionada, em parte, com a existência de forte dreno de carboidratos na raiz.An experiment was installed under greenhouse conditions to study growth depression in mycorrhizal citrus rootstocks at six P levels (0, 50, 100, 150, 200, and 250 mg kg-1, with and without (controls inoculation of the arbuscular mycorrhizal fungus (AMF (Glomus intraradices. The rootstock used was Citrus reshni Hort. Ex Tanaka, cv. Cleópatra, grown in an autoclaved, limed mixture (3:1 of a soil with low available P and washed sand. There were five replicates per treatment, in a random 6 x 2 factorial design. Six months after transplanting the seedlings, the plants were harvested and analyzed. The following characteristics were considered: plant growth, shoot dry matter, leaf area, transpiration and stomatal resistance. At the

  9. Genetic Transformation in Citrus

    Directory of Open Access Journals (Sweden)

    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.

  10. Flavonoids in Adaptation of Begonia grandis Dryander subsp. grandis Introduced in West Siberia (Novosibirsk

    Directory of Open Access Journals (Sweden)

    Karpova E.A.

    2016-08-01

    Full Text Available The dynamics of flavonoids (flavones and flavonols in leaves of Begonia grandis Dryander subsp. grandis plants introduced in Western Siberia (Central Siberian Botanical Garden, Siberian Branch of the Russian Academy of Sciences, Novosibirsk during the growing season in the greenhouse and the open ground were studied for the first time. The ranges of flavonoid fractions and individual flavonoids contents in a favorable environment and during periods of temperature drops and frost were established. Under favorable conditions in the greenhouse and in the open ground B. grandis subsp. grandis leaves were characterized by relatively low content of the sum of flavonoids (up to 10.1 mg/g. During periods of temperature drops in the greenhouse it was decreased (down to 5.2 mg/g, and in conditions of more considerable temperature drops and frost in open ground it was increased by several times (up to 28.3 mg/g. During the period of the action of stress factors content of the sum of flavonoid aglycones in the leaves was increased both in the greenhouse (including quercetin, luteolin and in the open ground (including quercetin, kaempferol, luteolin, in the open ground content of major constituent, luteolin 8-C-glucoside (orientin, was increased. The most significant transformations during the growing season were observed in the O-glycosides and free aglycones fractions, their contents of compounds and composition were varied. Four O-glycosides, including isoquercitrin, are detected only in the leaves of open ground plants.

  11. Pharmacognosy of Coccinia grandis:a review

    Institute of Scientific and Technical Information of China (English)

    Tamilselvan N; Thirumalai T; Elumalai EK; Balaji R; David E

    2011-01-01

    Traditional system of medicine consists of large number of plants with various medicinal and pharmacological importances and hence represents a priceless tank of new bioactive molecules. Coccinia grandis belongs to the family Cucurbitaceae. It is a rapidly growing, perennial climber or trailing vine. Traditionally different parts of this plant namely the roots, leaves and fruits are used in folklore medicine for several purposes like jaundice, diabetes, wound healing, ulcers, stomach ache, skin disease, fever, asthma, cough. The leaf and its constituents have been reported to possess hypoglycaemic, hypolipidemic and antioxidant properties. This review provides adequate information to develop suitable therapeutics out of these plant parts.

  12. The occurrence, prevention and cure of Exocarpium Citri Grandis plant diseases and insect pests%化橘红病虫害的发生与防治

    Institute of Scientific and Technical Information of China (English)

    蔡岳文; 严振; 丘金裕

    2004-01-01

    化橘红为芸香科植物化州柚(Citrus grandis(L)Osbeck var.tomentosa Hort)以未成熟果实的外果皮入药。近几年来,随着基地化、规模化大面积种植,其病虫害的发生及危害程度亦与日俱增,一些重要害虫已严重影响化橘红的生产和产品质量。

  13. 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.

  14. Seedling mycorrhiza

    DEFF Research Database (Denmark)

    Rasmussen, Hanne Nina; Rasmussen, Finn N.

    2014-01-01

    mycobionts suggest a derivation from a pathogenic relationship, and sister group comparison offers little support for derivation from other mycorrhizal relationships. A combination of in situ sowings and molecular identification of seedling mycobionts has established that a broad range of fungi besides...

  15. 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

  16. Influence of ozone and HCl gas on citrus and the vesicular-arbuscular mycorrhizal fungus Glomus fasciculatus

    Energy Technology Data Exchange (ETDEWEB)

    McCool, P.M.; Menge, J.A.; Taylor, O.C.

    1977-01-01

    One half of Troyer citrange (Poncirus trifoliata x Citrus sinensis) seedlings were grown from seed and inoculated during transplanting with Glomus fasciculatus. Inoculum consisted of soil and roots from sudangrass (Sorghum vulgare) containing hyphae, vesicles, arbuscles, and chlamydospores of G. fasciculatus. At 5, 12, and 16 weeks after inoculation, both inoculated and noninoculated seedlings were exposed to 110-140 mg/m/sup 3/ (73-92 ppm) HCl gas for 20 minutes or to 2 mg/m/sup 3/ (1 ppm) ozone for 4 hours. HCl produced moderate marginal leaf necrosis while ozone produced no visible symptoms. Control and HCl-exposed mycorrhizal seedlings were 28% and 36% taller, respectively, than corresponding nonmycorrhizal seedlings. Exposure to HCl reduced mycorrhizal seedling height by 24% compared to mycorrhizal controls. Ozone exposed mycorrhizal citrus were not significantly taller than non-mycorrhizal citrus but were 37% shorter than mycorrhizal controls. Total biomass of control and HCl-exposed mycorrhizal seedlings were greater than their nonmycorrhizal counterparts but the biomass was not significantly different between ozone-exposed seedlings. Spore production by G. fasciculatus was reduced 50% in ozone-exposed seedlings while spore populations of HCl-exposed seedlings were not statistically different from the controls.

  17. Drought tolerance, growth partitioning and vigor in eucalypt seedlings and rooted cuttings.

    Science.gov (United States)

    Blake, T J; Filho, W S

    1988-12-01

    To clarify the physiological basis of productivity differences among rooted cuttings and seedlings of eucalypt species, relationships between morphology and water relations were examined in 4-month-old seedlings of Eucalyptus grandis W. Hill ex Maiden, E. urophylla S.T. Blake and E. cloeziana F. Muell. and in 4-month-old rooted cuttings of three E. grandis cultivars. Four-month-old seedlings had greater dry weights, lower leaf area/root dry weight (LA/RDW) ratios and lower shoot/root dry weight (S/R) ratios than 4-month-old rooted cuttings. For all cultivars of E. grandis, tall rooted cuttings, as defined by height at age 4 weeks, had greater dry weights by age 4 months and lower LA/RDW and S/R ratios than short rooted cuttings. There were differences in height growth, dry matter productivity and relative shoot and root development among cuttings of different E. grandis cultivars, but these differences were not as great as the differences between short and tall grades of the same cultivar and between seedlings and cuttings. Consistent with the differences in LA/RDW and S/R ratios, seedlings had higher daytime water potentials (Psi(x)) than cuttings, and tall cuttings had higher daytime values of Psi(x) than short cuttings. Differences in Psi(x) were also related to stomatal conductance (g(wv)), which was up to 300% greater in short cuttings than in tall cuttings. Among seedlings, those of E. cloeziana, which had the smallest dry weight at age 4 months, had the highest g(wv), whereas those of E. grandis, which had the greatest dry weight at age 4 months, had the lowest g(wv). Unlike seedlings and the tall cuttings, short cuttings lost turgor when subjected to drought. The differences observed in susceptibility to water stress may account in part for the associated differences in dry matter production. Xylem pressure potential and relative water deficit at zero turgor did not differ significantly among the types of plants studied, which suggests that differences in

  18. 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.

  19. 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...

  20. 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.

  1. 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...

  2. Two-dimensional gel electrophoresis data in support of leaf comparative proteomics of two citrus species differing in boron-tolerance

    Directory of Open Access Journals (Sweden)

    Wen Sang

    2015-09-01

    Full Text Available Here, we provide the data from a comparative proteomics approach used to investigate the response of boron (B-tolerant ‘Xuegan’ (Citrus sinensis and B-intolerant ‘Sour pummelo’ (Citrus grandis leaves to B-toxicity. Using two-dimensional gel electrophoresis (2-DE technique, we identified 50 and 45 protein species with a fold change of more than 1.5 and a P-value of less than 0.05 from B-toxic C. sinensis and C. grandis leaves. These B-toxicity-responsive protein species were mainly involved in carbohydrate and energy metabolism, antioxidation and detoxification, stress responses, coenzyme biosynthesis, protein and amino acid metabolism, signal transduction, cell transport, cytoskeleton, nucleotide metabolism, and cell cycle and DNA processing. A detailed analysis of this data may be obtained from Sang et al. (J. Proteomics 114 (2015[1].

  3. Influência do vermicomposto na produção de mudas de Eucalyptus grandis Hill ex Maiden

    Directory of Open Access Journals (Sweden)

    Mauro Valdir Schumacher

    2001-01-01

    Full Text Available Considering the large area of planted forest with species of the genus Eucalyptus and its uses for multiple purpose, its cultivation has an economic importance in Brazil. The use of substratum with good physic-chemical characteristics is an important point for the quality of the produced seedlings. The objective of this work was to evaluate the effect of different doses of vermicompost in containers with capacity of about 50 cm3 of substratum. The current study was conducted in a greenhouse with Eucalyptus grandis from January to April in 1997. The substratum used for seedlings production was the soil from horizon A (0-20 cm of São Pedro Unit Mapping (yellow red Podzolic with different vermicompost quantities (0; 5.0; 10.0; 15.0 and 20.0 cm3. The vermicompost was produced from red-worm from California (Eisenia foetida Savigny with cow dung. After 100 days, the results of development for the same seedlings were different depending on doses of vermicompost. It was verified that quantities over 15.0 cm3 (30% of vermicompost per container are not recommended for the seedling production.

  4. Major phytochemical composition of 3 native Korean citrus varieties and bioactive activity on V79-4 cells induced by oxidative stress.

    Science.gov (United States)

    Yoo, Kyung Mi; Hwang, In Kyeong; Park, Ji Hyun; Moon, BoKyung

    2009-08-01

    Three citrus varieties grown in Korea, namely, Yuza (Citrus junos Sieb ex Tanaka), Kjool (Citrus unshiu Marcow), and Dangyooja (Citrus grandis Osbeck), were evaluated for their dietary fiber, total phenolics, total flavonoids, and total carotenoids as well as individual flavonoids composition. The biochemical characteristics of citrus varieties were examined by the antioxidant capacity (731 to 1221 micromol of Trolox equivalent/g), total phenolic (334 to 411 mg of chlorogenic acid equivalent/100 g), total flavonoid contents (214 to 281 mg of catechin equivalent/100 g), and total carotenoid contents (63 to 84 mg/100 g). Six flavonoids, including naringin, naringenin, hesperidin, hesperetin, neohesperidin, and luteolin, were tentatively identified. Naringin, hesperidin, and neohesperidin were the predominant flavonoids in 3 citrus varieties. Among the citrus varieties studied, Yuza showed higher antioxidant activity, total phenolics, total carotenoids, and lower superoxide radical scavenging assay (SRSA) IC(50) values than other varieties. Furthermore, Korean citrus showed higher protective effect on gap-junction intercellular communication (GJIC) as compared to vitamin C and luteolin.

  5. 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.

  6. INFLUENCE OF CITRUS LEPROSIS ON THE MINERAL COMPOSITION OF Citrus sinensis LEAVES

    Directory of Open Access Journals (Sweden)

    N. de L. Nogueira

    1996-05-01

    Full Text Available Citrus leprosis is the main viral disease affecting citrus in Brazil. Viral diseases can affect the mineral composition of citrus leaves, inducing mineral deficiencies. The aim of this work was to verify the influence of citrus leprosis on the mineral composition of citrus leaves, cultivar Pera. Orange seedlings were grown in pots containing sterile soil, and kept under greenhouse conditions. When plants had 15 to 20 leaves, they were infested with the mite Brevipalpus phoenicis, the leprosis vector, collected from infected citrus plants. Other plants were not infested, and were used as the control. Ninety days after infestation, all the infested plants presented leprosis lesions. The six upper leaves of each plant were collected and the determination of macro and micro-elements was performed. Leaves from the infected plants showed lower levels of N and higher levels of Ca, S and Fe, as compared to the control (= 0.05. Both treatments presented similar levels of P, K, Mg, Cu,Mn, Zn and B.A leprose dos citros é uma das principais doenças de citros no Brasil. As doenças causadas por vírus podem afetar a composição mineral de folhas de citros, induzindo deficiências minerais. Este trabalho teve como objetivo analisar a influência da leprose dos citros na composição mineral de folhas de citros, cultivar Pera. Seedlings de laranja foram crescidos em vasos contendo solo estéril e mantidos em casa de vegetação. Plantas com 15 a 20 folhas foram infestadas com ácaro da espécie Brevipalpus phoenicis, vetor da leprose dos citros, provenientes de plantas de citros com sintomas da doença. Outras plantas não foram infestadas, e serviram como controle. Após noventa dias, todas as plantas infestadas apresentavam lesões de leprose. Seis folhas da parte superior de cada planta foram coletadas para determinação dos teores de macro e micronutrientes. As folhas das plantas infectadas apresentaram níveis mais baixos de N e mais elevados de Ca, S

  7. Fertigação em mudas de citros utilizando-se mangueiras e microtubos sob regime de escoamento turbulento Fertigation on citrus seedlings using hoses and microtubes under turbulent flow regime

    Directory of Open Access Journals (Sweden)

    Wanderley J. Souza

    2011-08-01

    Full Text Available A irrigação localizada utilizando-se microtubo como emissor operando em regime de escoamento turbulento, pode ser uma alternativa viável, tanto técnica como economicamente para a produção de mudas de citros. Objetivou-se, com este trabalho, avaliar o desempenho de um sistema de fertigação na produção de mudas de laranja em viveiro projetado pelo modelo matemático universal, utilizando-se microtubos como emissores, sob regime de escoamento turbulento e comparar o desenvolvimento das plantas fertigadas por microtubos com o sistema em que se utiliza o método tradicional com mangueiras. No dimensionamento do comprimento dos emissores considerou-se o coeficiente K de dissipação de energia localizada através de um microtubo com diâmetro interno de 0,761 mm. O sistema de fertigação apresentou bom desempenho, com valores de grau de entupimento, uniformidade de Christiansen e uniformidade de emissão iguais a 0,50; 99,95 e 98,21%, respectivamente, após 160 dias de estudo. As plantas cultivadas via fertigação com microtubos e mangueiras, não apresentaram diferenças no que se refere ao diâmetro do caule e à altura. Desta forma, o uso de microtubo sob escoamento turbulento apresentou viabilidade técnica para fertigação.The use of localized irrigation using microtube as emitter under turbulent flow regime can be a technically feasible alternative. The objective of this study was to evaluate the performance of a fertigation system in nursery of citrus plants (greenhouse projected by universal mathematical model, using the microtubes as emitters, under turbulent flow rate and to compare the development of the fertigated plants by microtubes to the system that use the traditional method with hoses. In the size of the length of the emitters was considered the K coefficient of localized energy dissipation using a microtube with internal diameter of 0,761 mm. The fertigation system presented great performance with clogging degree

  8. Chemical control of the Asian citrus psyllid and of huanglongbing disease in citrus.

    Science.gov (United States)

    Boina, Dhana Raj; Bloomquist, Jeffrey R

    2015-06-01

    By 2014, huanglongbing (HLB), the most destructive disease of citrus, and its insect vector, the Asian citrus psyllid (ACP), Diaphorina citri (Kuwayama), became established in all major citrus-growing regions of the world, including the United States, with the exception of California. At present, application of insecticides is the most widely followed option for reducing ACP populations, while application of antibiotics for suppressing HLB disease/symptoms is being practiced in some citrus-growing regions. Application of insecticides during the dormant winter season, along with cultivation of HLB-free seedlings and early detection and removal of symptomatic and asymptomatic trees, has been very effective in managing ACP. Area-wide management of ACP by application of insecticides at low volume in large areas of citrus cultivation has been shown to be effective in managing HLB and reducing management costs. As insecticide resistance is a major problem in sustainable management of ACP, rotation/alternation of insecticides with different chemistries and modes of action needs to be followed. Besides control of the insect vector, use of antibiotics has temporarily suppressed the symptoms of HLB in diseased trees. Recent efforts to discover and screen existing as well as new compounds for their antibiotic and antimicrobial activities have identified some promising molecules for HLB control. There is an urgent need to find a sustainable solution to the HLB menace through chemical control of ACP populations and within HLB-infected trees through the judicious use of labeled insecticides (existing and novel chemistries) and antibiotics in area-wide management programs with due consideration to the insecticide resistance problem.

  9. Influência do aspecto nutricional de Eucalyptus grandis W. Hill ex Maiden na preferência alimentar da lagarta desfolhadora Eupseudosoma involuta (Lepidoptera - Arctiidae Influence of nutritional status of Eucalyptus grandis W. Hill ex Maiden on defoliating caterpillar Eupseudosoma involuta (Lepidoptera - Arctiidae dietary preference

    Directory of Open Access Journals (Sweden)

    Flávia Maria da Silva Carmo

    2004-10-01

    Full Text Available O objetivo deste trabalho foi investigar se o consumo de folhas de mudas de eucalipto por insetos herbívoros pode ser influenciado pela condição nutricional a que essas plantas estão submetidas. Para tal, mudas de Eucalyptus grandis W. Hill ex Maiden foram mantidas em soluções nutritivas, constituindo tratamentos diferenciados entre si pela presença e ausência dos macronutrrientes nitrogênio, fósforo e potássio, além da solução completa e da testemunha, sendo este último tratamento constituído somente por água destilada. Após as plantas estarem submetidas às diferentes condições de nutrição por 30 dias, suas folhas foram arrancadas e oferecidas como dieta a lagartas de Eupseudossoma involuta (Lepidoptera - Arctiidae. Decorridas 20 horas do início do período de alimentação, o restante da dieta de folhas foi pesado. Avaliaram-se os parâmetros altura e número de folhas das mudas de E. grandis antes e depois de submetidas aos tratamentos, bem como o peso das folhas antes e depois de serem oferecidas aos insetos. Concluiu-se que houve preferência alimentar das lagartas em função da nutrição com que as plantas de E. grandis eram mantidas.This work aimed at investigating whether the consumption of eucalyptus seedling leaves by a herbivorous insect can be affected by the nutritional condition to which these plants have been submitted. To do so, leaves of Eucalyptus grandis W. Hill ex Maiden seedlings (9 months old kept for 30 days in several nutrient solutions, were offered to Eupseudossoma involuta (Lepidoptera - Arctiidae caterpillars. Nutrient solutions differed from each other by the presence/absence of nitrogen, phosphorus and potassium. Control treatments consisted of a complete solution (N, P, K present and a treatment consisting of distilled water. The following parameters were measured: size and number of E. grandis leaves before and after having submitted to the treatments and leaf weight before and after they

  10. florescimento precoce em eucalyptus grandis1

    Directory of Open Access Journals (Sweden)

    Douglas Silva Domingues

    2006-01-01

    Full Text Available There are few available tools in eucalyptus breeding to accelerate the selection of superior genotypes, and one of the main tools to improve this process is the use of molecular markers linked to traits of interest. Using “Bulked Segregant Analysis”, we evaluated 81 RAPD molecular markers in a Eucalyptus grandis W. Hill ex Maiden progeny that segregates for early flowering, and one marker was identified as related to this trait. This RAPD marker was converted into a Sequence-Characterized Amplified Region (SCAR, which was then evaluated in a F1 progeny, and validated in other progenies that presents this trait. The SCAR marker was informative in the progeny in which one of the parental was the donor of the band, with an efficiency of 60%. These results describe the first SCAR marker developed for eucalypt and confirm this technique as a useful molecular tool for forestry breeding which could be employed to locate markers linked to other silvicultural traits.

  11. I Grandi Eventi: il caso spagnolo

    Directory of Open Access Journals (Sweden)

    Emilia Giovanna Trifiletti

    2008-08-01

    Full Text Available Il tema dell’articolo verte sulle trasformazioni urbane e territoriali generate dai grandi eventi in Spagna in relazione all’implementazione/trasformazione dei sistemi di trasporto durante gli stessi. A tale scopo l’articolo analizza i risultati, sia finali che attesi, delle trasformazioni degli ultimi 15 anni in Spagna in occasione di questi eventi straordinari. Nello specifico si analizzano cinque casi-studio: Barcellona ed i Giochi Olimpici del 1992, Siviglia e l’Esposizione Universale del 1992, Bilbao e la realizzazione del Museo Guggenheim (landmark architettonico nel 1997, Valencia e la Coppa America del 2007 e infine Saragozza e l’Expo del 2008 dove è stata realizzata una nuova stazione dell’Alta Velocità. Le occasioni, colte al volo dalle città spagnole, hanno modificato il volto dell’intero paese e negli ultimi quindici anni la Spagna si è dotata non solo di un nuovo grande patrimonio architettonico e di nuovi modelli di città, ma principalmente si è dotata di un sistema di trasporto (aeroporti, porti, metropolitane e strade moderno ed efficiente.

  12. Cellulose nanocrystal from pomelo (C. Grandis osbeck) albedo: Chemical, morphology and crystallinity evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Zain, Nor Fazelin Mat; Yusop, Salma Mohamad [Food Science Program, School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Selangor (Malaysia); Ahmad, Ishak [Polymer Research Centre (PORCE), School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Selangor (Malaysia)

    2013-11-27

    Citrus peel is one of the under-utilized waste materials that have potential in producing a valuable fibre, which are cellulose and cellulose nanocrystal. Cellulose was first isolated from pomelo (C. Grandis Osbeck) albedo by combination of alkali treatment and bleaching process, followed by acid hydrolysis (65% H{sub 2}SO{sub 4}, 45 °C, 45min) to produce cellulose nanocrystal. The crystalline, structural, morphological and chemical properties of both materials were studied. Result reveals the crystallinity index obtained from X-ray diffraction for cellulose nanocrystal was found higher than extracted cellulose with the value of 60.27% and 57.47%, respectively. Fourier transform infrared showed that the chemical treatments removed most of the hemicellulose and lignin from the pomelo albedo fibre. This has been confirmed further by SEM and TEM for their morphological studies. These results showed that cellulose and cellulose nanocrystal were successfully obtained from pomelo albedo and might be potentially used in producing functional fibres for food application.

  13. Biomass of clone of Eucalyptus grandis x urophylla for producing briquettes; Biomassa de clone de Eucalyptus grandis x Eucalyptus urophylla para producao de briquetes

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Eder Aparecido; Oguri, Guilherme [Universidade Estadual Paulista Julio de Mesquita Filho (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas], e-mail: os_garcias@fca.unesp.br; Lancas, Kleber Pereira [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Dept. de Engenharia Rural; Guerra, Saulo Philipe Sebastiao [Universidade Estadual Paulista Julio de Mesquita Filho (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Dept. de Gestao e Tecnologia Agroindustrial

    2011-07-01

    The aim of this work was conducted to address forest biomass energy for briquette producing. In an area of dystrophic soil, seedlings of clones of Eucalyptus grandis x E. urophylla were planted in 2008, considering factors spacing and fertilization. The first dosage of fertilizer was 70 g/plant of NPK 6-30-6 and total coverage of 110 g/plant of NPK 20-0-20 with B and Zn. The spacing was 2.8x0.5 m, 2.8x1.0 m, 2.8x1.5 m, 2.8x2.0 m and 2.8x2.5 m. At 18 months, tree samples were collected to evaluate the basic density of wood (BDW), dry biomass of stem, branches and leaves. An assessment of the economic viability of each treatment was based on the sale of briquettes. BDW spacing of 2.8x1.0 m was 0.464 kg/m{sup 3}. The largest biomass of the stem occurred in 2.8x0.5 m spacing, with dosage 3, but economically unviable. The dry biomass of branches was only affected by dosage, reaching 17.68 t/ha in the third dose. Only fertilization was significant for leaf biomass. The highest income in the spacing was 2.8 x1.5 m with dosage 2. (author)

  14. 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 ...

  15. Determination of the Presence of Huanglongbing in Seeds and Movement of the Pathogen in Citrus reticulata

    Directory of Open Access Journals (Sweden)

    Hajivand Shokrollah

    2009-01-01

    Full Text Available Problem statement: Huanglongbing (HLB also known as citrus greening disease is a fastidious phloem-inhabiting bacterium in the genus Candidatus Liberibacter. Using universal primers, the 16S ribosomal DNA sequence of three strains of the bacterium were obtained by PCR. However there is very little information on seed transmission and HLB pathogen movement to find a way for control or reduce the severity of HLB on the field. The study was conducted to detect HLB pathogen in seeds of Citrus, to determine pathogen movement in citrus seedling after infection and to detect the HLB pathogen in citrus roots. Approach: Seeds of Citrus reticulata cv. Limau Madu were collected from infected orchard and were germinated in screenhouse condition. The seeds of Citrus reticlata cv. L. Madu were planted in screenhouse too for HLB pathogen movement and HLB detection in roots. The seedlings were inoculated using infected grafting methods. Results: HLB was not amplified in new seedlings after germination. HLB moved slowly reaching up to 1.5 cm after 2 weeks, 1.5-4.5 cm after eight weeks and detected on 4.5-9 cm after 14 weeks below the grafting area. HLB was also detected up to 9-15 cm after 16 weeks, 15-24 cm after twenty weeks, 24-28.5 cm after 22 weeks and 28.5-30 cm after 24 weeks below the grafting area. Conclusion: Base on conventional PCR test, HLB disease in citrus is not seed borne and it can reach to the roots 26 weeks after inoculation.

  16. I caratteri tipicizzanti il paesaggio dei grandi laghi lombardi

    Directory of Open Access Journals (Sweden)

    Roberto Busi

    2013-01-01

    Full Text Available I sei grandi laghi lombardi costituiscono un distretto, posto tra l’alta pianura del Po e le Alpi, con spiccate caratteristiche paesistiche. L’ambiente fisico e biologico (ed, in particolare, la vegetazione e l’opera plurisecolare dell’uomo hanno infatti connotato il territorio con componenti la cui organica giustapposizione manifesta paesaggi che, ad un tempo, hanno forte unitarietà territoriale e spinta individualità. I grandi laghi lombardi costituiscono pertanto un importante patrimonio culturale e paesaggistico che necessita, per la sua conservazione e valorizzazione, di adeguata attenzione e sensibilità.

  17. PHARMACOLOGICAL IMPORTANCE OF CITRUS FRUITS

    Directory of Open Access Journals (Sweden)

    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. INDUCTION OF CALLUS FORMATION FROM DIFFERENT PARTS OF Citrus grandis (OSBECK FLOWERS

    Directory of Open Access Journals (Sweden)

    Zarina Binti Zakaria

    2010-01-01

    Full Text Available The objectives of the present work were to study the capability of pomelo's floral tissues to produce callus and to investigate the influence of plant growth regulators on callus induction and development. Various parts of flower namely petal, sepal, style, ovary, pistil and cup base were cultured onto Murashige and Skoog (MS basal medium supplemented with different levels of 2,4-dichlorophenoxyacetic acid (2,4-D, 6-benzylaminopurine (BAP and 6-Furfurylaminopurine (kinetin. It was found that different parts of flowers favored different levels of hormone for callus induction. The highest formation of callus were obtained from petal and sepal cultured on MS media supplemented with 1.5 mg/l kinetin. A 50 ± 2.3%explants from style and pistil had initiated callus when cultured on MS media supplemented with 0.05 mg/l and 0.10 mg/l BAP, respectively. On the other hand, sucrose agar (SA media alone had managed to induce callus formation from almost every part of the flowers with a success rate between 7.69 ± 0.32 to 50 ± 3.18%. The uncut part of flowers initiated high percentage of callus (14.6 ± 0.35% as shown in the study on petal.

  19. Biology of Anastrepha grandis (Diptera: Tephritidae) in Different Cucurbits.

    Science.gov (United States)

    Bolzan, Anderson; Nava, Dori E; Garcia, Flávio R M; Valgas, Ricardo A; Smaniotto, Giovani

    2015-06-01

    Anastrepha grandis (Macquart) (Diptera: Tephritidae) is one of the main pests of cucurbits in Brazil. Losses occur due to the damage caused to the fruits and the embargo on exports, as A. grandis is considered a quarantine pest in countries that import Brazilian cucurbits. This study aimed to evaluate the development of A. grandis in hosts of the Cucurbitaceae family. The hosts used were stem squash (Cucurbita pepo L.), squash (Cucurbita moschata Duchesne), chayote [Sechium edule (Jacq.) Swartz], mini watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai], Spanish melon (Cucumis melo L.), hybrid squash "Tetsukabuto" (C. moschata×Cucurbita maxima Duchesne), and salad cucumber (Cucumis sativus L.). We evaluated the viability and duration of egg-to-pupa period, pupal weight, sex ratio, and average number of pupae per fruit under controlled conditions of temperature, relative humidity, and photophase. The preoviposition and oviposition periods, fecundity, fertility, and longevity of females were determined for adults. Hosts of the genus Cucurbita provided a better development of A. grandis in comparison with other hosts, and presented a greater number of insects on fruit as well as higher infestation rate. Fecundity and longevity were also higher for females that developed in hosts of the genus Cucurbita, although values of these biological parameters varied between stem squash, squash, hybrid squash "Tetsukabuto."

  20. Cafe Grandis kõlab lautomuusika / Anneli Remme

    Index Scriptorium Estoniae

    Remme, Anneli, 1968-

    2008-01-01

    Corelli Musicu salongiõhtutel festivali "Fiesta de la Guitarra" raames esineb trio koosseisus Stewart McCoy (lautomängija), Robert Staak (lautomängija) ja Maria Staak (laulja), esinejatest. Esitatakse renessansiaja autorite lautoduette ja -laule. Kontsert 8. nov. Pärnu hotellis sarjas "Café Grandi muusikasalong"

  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. 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.

  3. Efeito alelopático de plantas daninhas e concentrações de capim-braquiária (Brachiaria decumbens no desenvolvimento inicial de eucalipto (Eucalyptus grandis Allelopathic effect of weeds and concentrations of Brachiaria decumbens on the initial development of eucalyptus (Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    L.S. Souza

    2003-12-01

    (Eucaliptus grandis. In the first experiment, Bracharia decumbens (BRADC caused the strongest effects mainly on the development of the upper part of the plants. In the second experiment, BRADC dry matter was added to the soil to evaluate the effect on the initial development of E. grandis seedlings. The dry matter concentrations evaluated were: 0% (check, 0.5%, 1%, 2%, 3% w/w, incorporated into the soil. The experiment was replicated, by adding identical total quantities of carbon to the treatments. The amount of carbon was adjusted by adding Sphagnum. Soil solution was extracted through porous porcelain capsules placed in the pots (39 days after E. grandis seedling transplantation. The following analyses of soil solutions collected at the end of the tests were performed: pH and electric conductivity, osmotic potential,and nutrient level analysis. Soil solution analysis of the treatments allowed to conclude that the nutrient level and the chemical characteristics of the solutions were slightly altered by the treatments, being unlikely that the reduction of E. grandis is due to restrictions on the quantities of the available nutrients.

  4. 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

  5. Potential Nutritional Benefits of Current Citrus Consumption

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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. Experimental Evidence and In Silico Identification of Tryptophan Decarboxylase in Citrus Genus

    Directory of Open Access Journals (Sweden)

    Luigi De Masi

    2017-02-01

    Full Text Available Plant tryptophan decarboxylase (TDC converts tryptophan into tryptamine, precursor of indolealkylamine alkaloids. The recent finding of tryptamine metabolites in Citrus plants leads to hypothesize the existence of TDC activity in this genus. Here, we report for the first time that, in Citrus x limon seedlings, deuterium labeled tryptophan is decarboxylated into tryptamine, from which successively deuterated N,N,N-trimethyltryptamine is formed. These results give an evidence of the occurrence of the TDC activity and the successive methylation pathway of the tryptamine produced from the tryptophan decarboxylation. In addition, with the aim to identify the genetic basis for the presence of TDC, we carried out a sequence similarity search for TDC in the Citrus genomes using as a probe the TDC sequence reported for the plant Catharanthus roseus. We analyzed the genomes of both Citrus clementina and Citrus sinensis, available in public database, and identified putative protein sequences of aromatic l-amino acid decarboxylase. Similarly, 42 aromatic l-amino acid decarboxylase sequences from 23 plant species were extracted from public databases. Potential sequence signatures for functional TDC were then identified. With this research, we propose for the first time a putative protein sequence for TDC in the genus Citrus.

  8. 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.

  9. Production and development of eucalyptus seedlings in function of doses of phosphorus

    Directory of Open Access Journals (Sweden)

    José Henrique Tertulino Rocha

    2013-12-01

    Full Text Available This study evaluated the effect of phosphorus (P on the survival in the nursery and early development in the field of clonal Eucalyptus urophylla x Eucalyptus grandis seedlings. The experimental design was completely randomized with four treatments and five replicates of 30 plants per replicate. At the end of the cycle (90 days, 15 seedlings were used for determining the dry matter accumulation and nutrient concentration in the shoot. The rest was planted in the field to determine the percentage of survival and early development. The treatments consisted of four doses of P fertilization (0.0, 1.3, 2.6 and 5.2 mg plant-1. To obtain high quality seedlings in conditions similar to this experiment it is required doses of P in the range from 3.6 to 3.8 mg plant-1. Doses greater than 4 mg plant-1 affect the development and quality of eucalyptus seedlings. An adequate phosphorus fertilization of eucalyptus seedlings increase, by about 30%, the percentage of surviving seedlings in the field.

  10. 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,...

  11. Culture Technology of Citrus medica var.sarcodactylis%佛手丰产栽培技术

    Institute of Scientific and Technical Information of China (English)

    邹文武; 朱雯

    2014-01-01

    文章介绍了佛手的生物学特性、种苗繁育、栽植技术和主要病虫害防治等,为佛手栽培种植提供技术指导。%Cultrue technology of Citrus medica var.sarcodactylis was introduced in this article,which in-cluding technology in seedling breeding,planting and method of main disease and pest control.

  12. Nutrient utilization in some tropical forest tree seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Lalman, M.A.

    1985-01-01

    The concentration of N, P, K, Ca and Na in seedlings of Dalbergia sissoo, Tamarindus indica, Diospyros melanoxylon, Terminalia arjuna and Tectona grandis was evaluated in field plantings in Uttar Pradesh, from the age of 1 to 12 months (April 1978 to March 1979). In all species, concentration of Na in leaves was higher than that of K, Ca and P (highest in D. melanoxylon) and was higher in leaves than in roots and stems. Concentration was found to increase with age of leaves up to 8-9 months (at the time of yellowing), after which N, P and K contents decreased rapidly. N, P and K content of stems and roots showed steady increase with age, but Ca and Na, after showing increases up to 8-10 months showed a slight reduction in the 11th and 12th months. 51 references.

  13. Observações citológicas em citrus: ll. variedades triplóides

    Directory of Open Access Journals (Sweden)

    C. A. Krug

    1944-01-01

    Full Text Available No presente trabalho apresenta-se um breve resumo dos conhecimentos atuais sôbre a citologia do gênero Citrus; descrevem-se, a seguir, duas variedades triplóides de interêsse econômico. Admite-se que uma delas se tenha derivado da outra por meio de um "seedling" nucelar. Os caracteres morfológicos e citológicos dêstes triplóides são apresentados em detalhes. Chama-se a atenção para a importância da triploidia nos trabalhos de melhoramento das plantas cítricas.A review is presented of citrus cytology and account is given of the author's investigations of this subject. Two triploid citrus varieties are described which are of economic importance. It appears probable that one of these is a nucellar seedling derived from the other. The morphological and cytological characteristics of these triploids are given in detail. Attention is called to the importance of triploidy in citrus breeding.

  14. 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...

  15. The Study of Seedlings

    NARCIS (Netherlands)

    Jacobs, M.

    1966-01-01

    ”The seedling represents the most critical stage in the life of a tree. Conditions of seeding and germination may be entirely favourable, and natural seedlings may appear in countless quantities at the beginning of the rainy season, only to disappear largely or entirely within a comparatively short

  16. 广东曲江区柑橘园天敌瓢虫种类调查及食性观察(鞘翅目:瓢虫科)%Survey and preys of lady beetles (Coccinellidae) in citrus groves in Qujiang, Guangdong

    Institute of Scientific and Technical Information of China (English)

    郑朝武; 虞国跃

    2013-01-01

    对广东曲江区4个柑橘园4种橘类植物(甜橙Citrus sinensis(Linn.)Osbeck,沙田柚Citrus grandis(Linn.)Osbeck var.shatinyu Hort,温州蜜橘Citrus unshiu Marcovitch和沙糖桔Citrus reticulata Blanco cv.Shiyue Ju)上的瓢虫进行种类调查和食性观察,共采集320头瓢虫标本,鉴定结果为24属51种,多数为蚜虫的捕食性天敌,其中龟纹瓢虫、六斑月瓢虫、红肩瓢虫、黄斑盘瓢虫、台湾隐势瓢虫、后斑小瓢虫和细缘唇瓢虫为优势种.对大多数种类的食性作了观察或进行室内饲养,基本明确了它们在橘类上的猎物.%Survey and preys of lady beetle species in citrus groves were carried out in Qujiang District, Shaoguan City, Guangdong Province between January 2010 to July 2012. The surveyed 4 Citrus plants are Citrus sinensis (Linn. ) Osbeck, C. grandis (Linn. ) Osbeck var. shatinyu Hort, C. unshiu Marcovitch and C. reticulata Blanco cv. Shiyue Ju. A total of 320 lady beetle specimens (excluding plant -eating ones) were collected and identified. They belonged to 51 species of 24 genera. Most of them are predator of citrus aphids, and Propylea japonica (Thunberg, 1781), Cheilomems sexmaculata (Fabricius, 1781), Harmonia dimidiata ( Fabricius, 1755), Lemnia saucia ( Mulsant, 1850), Cryptogonus horishanus (Ohta, 1929), Scymnus (Pullus) posticalis Sicard, 1912 and Chilocorus circumdatus (Gyhhenhal, 1808) were dominant species. Most of them are provided with the observed preys in field or the feeding preys indoor.

  17. Grandi Eventi: indicatori di classificazione e incidenza sui sistemi urbani

    Directory of Open Access Journals (Sweden)

    Giuseppe Mazzeo

    2008-08-01

    Full Text Available I grandi eventi sono ritenuti una opportunità per le città in quanto sono uno straordinario catalizzatore di investimenti mirati alla trasformazione della città. L’azione dei grandi eventi non è confinata solo nel periodo di svolgimento dell’evento stesso ma si estende ad un periodo molto più ampio, prima e, soprattutto, dopo il suo termine. Nell’organizzazione delle manifestazioni più recenti le trasformazioni urbane hanno interessato in modo sempre maggiore parti già in precedenza urbanizzate, al punto che l’evento diviene l’occasione per trasformare la città costruita e per modificarne il profilo. Il paper approfondisce l’argomento della classificazione degli eventi e del loro impatto sul sistema urbano sviluppandosi in tre parti. Nella prima si analizzano due tipologie di grandi eventi (le esposizioni internazionali e i giochi olimpici con l’obiettivo di pervenire ad una definizione condivisa. Nella seconda parte si identificano i più importanti fattori ed indicatori per l’analisi di questa specifica categoria di avvenimenti. Infine, nella terza parte, si approfondiscono i fattori connessi all’impatto sul sistema urbano e all’organizzazione della sua mobilità. In particolare, viene approfondito il concetto di “effetto pulsar”, ossia gli effetti moltiplicativi sulla evoluzione urbana dipendenti dalla organizzazione di eventi multipli in parallelo o in sequenza. Uno degli elementi più negativi connessi alla organizzazione di un grande evento è la dispersione nel tempo dei benefici acquisiti grazie ad esso; per evitare ciò è necessario che l’evento sia seguito da politiche strategiche continue in modo da preservare i vantaggi acquisiti.

  18. Evaluation of substrates on the emergence of "araticum-de-terra-fria" (Annona emarginata (Schltdl. H. Rainer Seedlings

    Directory of Open Access Journals (Sweden)

    Daniel Baron

    2011-06-01

    Full Text Available Choosing a substrate is the determinant factor for the seedling producer; thus, the aim of this study was to evaluate the effect of different types of substrates on the emergence of "araticum-de-terra-fria" (Annona emarginata (Schltdl. H. Rainer seedlings. The experiment was carried out in a greenhouse and the experimental design was in randomized blocks, with three treatments and five replicates of 72 seeds per plot. The treatments consisted of the following substrates: coconut fiber, vermiculite and Plantmax® Citrus. The number of emerged seedlings was weekly counted for 105 days. Data regarding seedling height were obtained, and the emergence velocity index and mean time, besides total emergence percentage and that over time were calculated. Results from total mean emergence percentage, seedling height, emergence velocity index (EVI, and mean emergence time (MET were subjected to analysis of variance and means were compared by the Tukey's test at 5% significance. The curves concerning the emergence percentage over time were fit by the logistic growth equation for each treatment and the means of each parameter (A, B, C were compared by the Duncan's test at 5% significance. The substrates vermiculite led to the highest values of emergence percentage differing from the PlantMax® Citrus, but not of the coconut fiber, however the vermiculite promoted seedling height in a shorter time; therefore, this substrate is recommended for the initial development of "araticum-de-terra-fria" (Annona emarginata (Schltdl. H. Rainer seedlings.

  19. Isoflavonoids in the Rutaceae family: 1. Fortunella obovata, Murraya paniculata and four Citrus species.

    Science.gov (United States)

    Lapcík, Oldrich; Klejdus, Borivoj; Davidová, Michaela; Kokoska, Ladislav; Kubán, Vlastimil; Moravcová, Jitka

    2004-01-01

    Several types of compounds with immunoreactivity similar to isoflavonoids were detected in water: ethanol extracts of leaves of Fortunella obovata Hort. ex Tanaka, Murraya paniculata Jack. and four Citrus species, namely C. aurantium L, C. grandis Osbeck, C. limonia Osbeck., and C. sinensis Osbeck (Rutaceae). The chromatographic mobilities of the immunoreactive substances were compared with those of authentic standards, revealing a spectrum of isoflavonoid metabolites in all plants studied. Aglycones as well as glycosides were recognized, namely daidzin, genistin, daidzein, genistein, formononetin, biochanin A, prunetin, and several incompletely characterized isoflavonoids. A subsequent HPLC-MS study verified the identities of the main immunoreactive isoflavonoids and established the identities of several others, viz. glycitein, glycitin, ononin and sissotrin, including the malonylated and acetylated isoflavonoid glucosides. The estimated content of the individual immunoreactive entities ranged from a few microg to about 2 mg/kg (dry weight). It is concluded that the isoflavonoid metabolic pathway is present throughout the Rutaceae family.

  20. 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

    Background and Aims Polyploidy is a major component of plant evolution. The citrus gene pool is essentially diploid but tetraploid plants are frequently encountered in seedlings of diploid apomictic genotypes. The main objectives of the present study were to establish the origin of these tetraploid plants and to ascertain the importance of genotypic and environmental factors on tetraploid formation. Methods Tetraploid seedlings from 30 diploid apomictic genotypes were selected by flow cytometry and genotyped with 24 single sequence repeat (SSR) markers to analyse their genetic origin. Embryo rescue was used to grow all embryos contained in polyembryonic seeds of ‘Tardivo di Ciaculli’ mandarin, followed by characterization of the plantlets obtained by flow cytometry and SSR markers to accurately establish the rate of tetraploidization events and their potential tissue location. Inter-annual variations in tetraploid seedling rates were analysed for seven genotypes. Variation in tetraploid plantlet rates was analysed between different seedlings of the same genotype (‘Carrizo’ citrange; Citrus sinensis × Poncirus trifoliata) from seeds collected in different tropical, subtropical and Mediterranean countries. Key Results Tetraploid plants were obtained for all the studied diploid genotypes, except for four mandarins. All tetraploid plants were identical to their diploid maternal line for SSR markers and were not cytochimeric. Significant genotypic and environmental effects were observed, as well as negative correlation between mean temperature during the flowering period and tetraploidy seedling rates. The higher frequencies (20 %) of tetraploids were observed for citranges cultivated in the Mediterranean area. Conclusions Tetraploidization by chromosome doubling of nucellar cells are frequent events in apomictic citrus, and are affected by both genotypic and environmental factors. Colder conditions in marginal climatic areas appear to favour the expression of

  1. Potential impacts of using sewage sludge biochar on the growth of plant forest seedlings

    Directory of Open Access Journals (Sweden)

    Maria Isidoria Silva

    Full Text Available ABSTRACT: Sewage sludge has long been successfully used in the production of nursery plants; however, some restriction may apply due to its high pathogenic characteristics. The process of charring the organic waste significantly reduces that undesired component and may be as effective as the non-charred residue. The aim of this study was to evaluate the effect of sewage sludge biochar on the growth and morphological traits of eucalyptus ( Eucalyptus grandis L. seedlings, and compare results with those observed when using uncharred sewage sludge. Treatments were arranged in a completely randomized design, in a 2 x 2 factorial scheme, with four replications. Charred and non-charred sewage sludge were tested with and without NPK addition. A control treatment was also evaluated. Ten weeks old eucalyptus seedlings were transferred to the pots and grew for eight weeks. Chlorophyll content, plant height and stem diameter were measured at 0, 30 and 60 days after transplant. Shoot and root biomass were measured after plant harvest. Dickson Quality Index was calculated to evaluate the overall quality of seedlings. Biochar was effective in improving the seedlings quality, and had similar effects as the non-charred waste. Therefore, sewage sludge biochar has the potential to improve the process of production of forest species seedlings and further reduce the environmental risks associated with the use of non-charred sewage sludge.

  2. Visualization of ‘Ca. Liberibacter asiaticus’ cells in the vascular bundle of citrus seed coats with fluorescence in situ hybridization and transmission electron microscopy

    Science.gov (United States)

    ‘Ca. Liberibacter asiaticus’ is the bacterium implicated as a causal agent of the economically damaging disease of citrus called huanglongbing (HLB). Vertical transmission of the organism through seed to the seedling has not been demonstrated, but previous studies using real-time PCR (qPCR) assays ...

  3. EMERGÊNCIA E DESENVOLVIMENTO INICIAL DE PLÂNTULAS DE Cassia grandis L. f. EM FUNÇÃO DE DIFERENTES SUBSTRATOS

    Directory of Open Access Journals (Sweden)

    Caio César Pereira Leal

    2016-01-01

    Full Text Available ABSTRACT Currently, it is aimed to use substrates composed primarily of organic waste in order to reduce costs with chemical fertilizer. In that sense, the experiment was to evaluate different types of substrates for the emergence and early development of seedlings of Cassia grandis L. f. The experiment was carried out in a greenhouse at the Departament of Vegetable Sciences of Federal Rural do Semi- Árido (UFERSA, in Mossoró, Rio Grande do Norte state, Brazil. The substrates used were: sand + carbonized rice husk (in ratios of 1:1, 1:3 and 3:1, plant sand + wood dust (in ratios of 1:1, 1:3 and 3:1, plant sand + coconut fiber (in ratios of 1:1, 1:3 and 3:1, plant sand + chestnut bark (in ratios of 1:1, 1:3 and 3:1 and plant sand (control. The experimental design was a completely randomized design with 13 treatments (combinations of substrates, with four replications of 25 seeds and the means to test for Skot-knot (pr <0.05. We evaluated the following variables: plant emergence, emergence speed, plant height, root length and weight of the aerial part of the plant, root dry mass and total dry mass. According to the results, the substrate plant sand + sawdust (1:1 and plant sand + coconut fiber (1:3 showed higher values, providing better results in emergence, weight of the aerial part of the plant, length of the aerial part of the plant, root dry mass and root length. It was found that the substrate compounds sand plant and chestnut bark (1:3 is harmful to the emergence of seedling of Cassia grandis .

  4. 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...

  5. 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.

  6. Bicarbonate blocks iron translocation from cotyledons inducing iron stress responses in Citrus roots.

    Science.gov (United States)

    Martínez-Cuenca, Mary-Rus; Legaz, Francisco; Forner-Giner, M Ángeles; Primo-Millo, Eduardo; Iglesias, Domingo J

    2013-07-01

    The effect of bicarbonate ion (HCO3(-)) on the mobilization of iron (Fe) reserves from cotyledons to roots during early growth of citrus seedlings and its influence on the components of the iron acquisition system were studied. Monoembryonic seeds of Citrus limon (L.) were germinated "in vitro" on two iron-deprived media, supplemented or not with 10mM HCO3(-) (-Fe+Bic and -Fe, respectively). After 21d of culture, Fe concentration in seedling organs was measured, as well as gene expression and enzymatic activities. Finally, the effect of Fe resupply on the above responses was tested in the presence and absence of HCO3(-) (+Fe+Bic or +Fe, respectively). -Fe+Bic seedlings exhibited lower Fe concentration in shoots and roots than -Fe ones but higher in cotyledons, associated to a significative inhibition of NRAMP3 expression. HCO3(-) upregulated Strategy I related genes (FRO1, FRO2, HA1 and IRT1) and FC-R and H(+)-ATPase activities in roots of Fe-starved seedlings. PEPC1 expression and PEPCase activity were also increased. When -Fe+Bic pre-treated seedlings were transferred to Fe-containing media for 15d, Fe content in shoots and roots increased, although to a lower extent in the +Fe+Bic medium. Consequently, the above-described root responses became markedly repressed, however, this effect was less pronounced in +Fe+Bic seedlings. In conclusion, it appears that HCO3(-) prevents Fe translocation from cotyledons to shoot and root, therefore reducing their Fe levels. This triggers Fe-stress responses in the root, enhancing the expression of genes related with Fe uptake and the corresponding enzymatic activities.

  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. 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...

  10. GROWTH AND ARCHITECTURE OF ROOT SYSTEMS OF PLANTS OF Eucalyptus camaldulensis, E. GRANDIS AND E. PELLITA WERE EVALUATED AFTER THE PLANTING

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio dos Santos Leles

    2001-01-01

    Full Text Available The seedlings were produced according to two methodologies: pressed blocks and stiff plastic tubes. A mixture of decomposed sugar-cane bagasse (60% and industrial sugar-cane plant residues (40% were used as substrate. The blocks were made by pressing the humid substrate in metallic moulds with the dimensions of 60 x 40 x 20 cm (lenght, width and height and pressure of 10 kgf/cm2 for 15 minutes. Under this load the blocks height was reduced to 10 cm. They were placed in wooden boxes with screen bottom. The stiff plastic tubes had circular section 12 cm high, with volume capacity of 50 cm3. The seeds were sown in the blocks 5 cm apart, by means of a spatula. At the end of nursey phase, the seedlings were planted the field. After 2, 6 and 10 months of planting, the height and the diameter at the ground level were evaluated. At the age of 10 months it was also evaluated the number of laterals root and deformatiom cofficient the three plants for treatment. Two months after planting, the plants originated from the pressed blocks showed growth highly signifficant in relation to those of the stiff plastic tubes. At 10 months, of age only Eucalyptus grandis seedlings showed significant difference concerning to height and diameter at the ground level between plants produced by pressed blocks and stiff plastic tubes. For the three species, the pressed blocks seedling showed higher number of lateral roots and smaller number of root deformation coefficents in comparision to the plants from the stiff tubes.

  11. Study on Machining Properties of Eucalyptus urophylla × E. Grandis: Ⅰ. Planing and Sanding Properties

    Institute of Scientific and Technical Information of China (English)

    HOU Xinyi; JIANG Xiaomei; GAO Jianmin; YIN Yafang

    2006-01-01

    The research method in this paper is based on the standard of American Society for Testing and Materials (ASTM), Planing and sanding are selected to study the machining properties of E. Urophylla × E. Grandis plantation wood. Moreover, the reasons for machining defects are analyzed. The results show E. Urophylla × E. Grandis planted in south China is a good species with a great potential for solid wood utilization.

  12. [Community features of Sacrabaeoida larvae in Stipa grandis steppe].

    Science.gov (United States)

    Xinmin, Liu; Ning, Wu

    2004-09-01

    The study showed that in the Stipa grandis steppe of Inner Mongolia, there were 4 families and 9 species of Scarabaeoidea larvae, among which, the numbers of species and individuals of Melolonthidae were more than those of other families. The important value of the dominant species in Scarabaeoidea larvae community were Trematodes tenebrioides > Serica orientalis > Amphimallon solstitialis > Cyriopertha arcuata. Based on the features of their seasonal dynamics, they could be classified into three kinds. The first kind was that their density peak occurred in spring and autumn, such as Serica orientalis. Cyriopertha arcuata belonged to the second kind, and its density had no obvious fluctuation through all the year. Trematodes tenebrioides and Amphimallon solstitialis could be classified into the third kind, and their density peak all occurred in autumn. The biodiversity index of Scarabaeoidea larvae community was relatively higher in autumn than in spring and summer. Although the richness of Scarabaeoidea larvae populations was not lower in spring, their composition was very simple.

  13. Response of Eucalyptus grandis trees to soil water deficits.

    Science.gov (United States)

    Dye, P. J.

    1996-01-01

    The use of potential transpiration models to simulate transpiration rates in areas prone to soil water deficits leads to overestimates of water use as the soil dries. Therefore, I carried out studies on Eucalyptus grandis W. Hill ex Maiden trees subjected to soil drying at two field sites in the Mpumalanga province of South Africa to determine the relation between transpiration rate and soil water availability. I hypothesized that, with this relationship defined, simple modeling of the soil water balance could be used to predict what fraction of potential transpiration was taking place at a given time. Site 1 supported a stand of 3-year-old E. grandis trees, whereas 9-year-old trees were growing on Site 2, situated 2 km away. At each site, plastic sheeting was laid over the ground to prevent soil water recharge and thereby allow the roots in the soil to induce a continuous progressive depletion of soil water. Measurements of predawn xylem pressure potential, leaf area index, growth and sap flow rates revealed that prevention of soil water recharge resulted in only moderate drought stress. At Site 1, the trees abstracted water down to 8 m below the surface, whereas trees at Site 2 obtained most of their water from depths below 8 m. I found that modeling the water balance of deep rooting zones is impractical for the purpose of simulating nonpotential transpiration rates because of uncertainties about the depth of the root system, the soil water recharge mechanism and the water retention characteristics of the deep subsoil strata. I conclude that predicting the occurrence and severity of soil water deficits from the soil water balance is not feasible at these sites.

  14. 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

  15. Isolation and Characterization of Activators of ERK/MAPK from Citrus Plants

    Directory of Open Access Journals (Sweden)

    Takashi Yoshida

    2012-02-01

    Full Text Available Extracellular signal-regulated kinases 1/2 (ERK1/2, components of the mitogen-activated protein kinase (MAPK signaling cascade, have been recently shown to be involved in synaptic plasticity and in the development of long-term memory in the central nervous system (CNS. We therefore examined the ability of Citrus compounds to activate ERK1/2 in cultured rat cortical neurons, whose activation might have a protective effect against neurodegenerative neurological disorders. Among the samples tested, extracts prepared from the peels of Citrus grandis (Kawachi bankan were found to have the greatest ability to activate ERK1/2. The active substances were isolated by chromatographic separation, and one of them was identified to be 3,5,6,7,8,3′,4′-heptamethoxyflavone (HMF. HMF significantly induced the phosphorylation of cAMP response element-binding protein (CREB, a downstream target of activated ERK1/2, which appears to be a critical step in the signaling cascade for the structural changes underlying the development of long-term potentiation (LTP. In addition, the administration of HMF into mice treated with NMDA receptor antagonist MK-801 restored the MK-801-induced deterioration of spatial learning performance in the Morris mater-maze task. Taken together, these results suggest that HMF is a neurotrophic agent for treating patients with memory disorders.

  16. Neurotrophic Effect of Citrus Auraptene: Neuritogenic Activity in PC12 Cells

    Directory of Open Access Journals (Sweden)

    Mitsunari Nakajima

    2012-04-01

    Full Text Available The activation of extracellular signal-regulated kinases (ERK leads to a number of cellular changes associated with the development of long-term memory. Using cultured cortical neurons, we previously showed that the n-hexane extract prepared from the peels of Citrus grandis (Kawachi bankan induces the activation of ERK1/2 and that one of the compounds with this ability in the extract is 3,5,6,7,8,3′,4′-heptamethoxyflavone (HMF, a Citrus polymethoxyflavone. In fact, we found that HMF has the ability to rescue mice from drug-induced learning impairment. This hexane extract contains auraptene (AUR, a coumarin derivative with a monoterpene unit, together with HMF. The present study was designed to investigate the effect of AUR in vitro. Our results show that 1 AUR had the ability to induce the activation of ERK1/2 in not only cortical neurons but also the rat pheochromocytoma cell line (PC12 cells, which is a model system for studies on neuronal proliferation and differentiation; and 2 AUR had the ability to promote neurite outgrowth from PC12 cells.

  17. Complex history of admixture during citrus domestication revealed by genome analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G. Albert; Prochnik, Simon; Jenkins, Jerry; Salse, Jerome; Hellsten, Uffe; Murat, Florent; Perrier, Xavier; Ruiz, Manuel; Scalabrin, Simone; Terol, Javier; Takita, Marco Aur& #233; lio,; Labadie, Karine; Poulain, Julie; Couloux, Arnaud; Jabbari, Kamel; Cattonaro, Federica; Fabbro, Cristian Del; Pinosio, Sara; Zuccolo, Andrea; Chapman, Jarrod; Grimwood, Jane; Tadeo, Francisco; Estornell, Leandro H.; Mu?oz-Sanz, Juan V.; Ibanez, Victoria; Herrero-Ortega, Amparo; Aleza, Pablo; P& #233; rez, Juli& #225; n P& #233; rez,; Ramon, Daniel; Brunel, Dominique; Luro, Francois; Chen, Chunxian; Farmerie, William G.; Desany, Brian; Kodira, Chinnappa; Mohiuddin, Mohammed; Harkins, Tim; Fredrikson, Karin; Burns, Paul; Lomsadze, Alexandre; Borodovsky, Mark; Reforgiato, Giuseppe; Freitas-Astua, Juliana; Quetier, Francis; Navarro, Luis; Roose, Mikeal; Wincker, Patrick; Schmutz, Jeremy; Morgante, Michele; Machado, Marcos Antonio; Talon, Manuel; Jaillon, Olivier; Ollitrault, Patrick; Gmitter, Frederick; Rokhsar, Daniel

    2014-06-30

    vulnerable to disease outbreaks, including citrus greening disease (also known as Huanglongbing) that is rapidly spreading throughout the world's major citrus producing regions1. Understanding the population genomics and domestication of citrus will enable strategies for improvements to citrus including resistance to greening and other diseases. The domestication and distribution of edible citrus types began several thousand years ago in Southeast Asia and spread globally following ancient land and sea routes. The lineages that gave rise to most modern cultivated varieties, however, are lost in undocumented antiquity, and their identities remain controversial2, 3. Several features of Citrus biology and cultivation make deciphering these origins difficult. Cultivated varieties are typically propagated clonally by grafting and through asexual seed production (apomixis via nucellar polyembryony) to maintain desirable combinations of traits (Fig. 1). Thus many important cultivar groups have characteristic basic genotypes that presumably arose through interspecific hybridization and/or successive introgressive hybridizations of wild ancestral species. These domestication events predated the global expansion of citrus cultivation by hundreds or perhaps thousands of years, with no record of the domestication process. Diversity within such groups arises through accumulated somatic mutations, generally without sexual recombination, either as limb sports on trees or variants among apomictic seedling progeny. Two wild species are believed to have contributed to domesticated pummelos, mandarins and oranges. Based on morphology and genetic markers, pummelos have generally been identified with the wild species C. maxima (Burm.) Merrill that is indigenous to Southeast Asia. Although mandarins are similarly widely identified with the species C. reticulata Blanco 4-6, wild populations of C. reticulata have not been definitively described. Various authors have taken dif

  18. Reduced Susceptibility to Xanthomonas citri in Transgenic Citrus Expressing the FLS2 Receptor From Nicotiana benthamiana.

    Science.gov (United States)

    Hao, Guixia; Pitino, Marco; Duan, Yongping; Stover, Ed

    2016-02-01

    Overexpression of plant pattern-recognition receptors by genetic engineering provides a novel approach to enhance plant immunity and broad-spectrum disease resistance. Citrus canker disease associated with Xanthomonas citri is one of the most important diseases damaging citrus production worldwide. In this study, we cloned the FLS2 gene from Nicotiana benthamiana cDNA and inserted it into the binary vector pBinPlus/ARS to transform Hamlin sweet orange and Carrizo citrange. Transgene presence was confirmed by polymerase chain reaction (PCR) and gene expression of NbFLS2 was compared by reverse transcription quantitative PCR. Reactive oxygen species (ROS) production in response to flg22Xcc was detected in transgenic Hamlin but not in nontransformed controls. Low or no ROS production was detected from nontransformed Hamlin seedlings challenged with flg22Xcc. Transgenic plants highly expressing NbFLS2 were selected and were evaluated for resistance to canker incited by X. citri 3213. Our results showed that the integration and expression of the NbFLS2 gene in citrus can increase canker resistance and defense-associated gene expression when challenged with X. citri. These results suggest that canker-susceptible Citrus genotypes lack strong basal defense induced by X. citri flagellin and the resistance of these genotypes can be enhanced by transgenic expression of the flagellin receptor from a resistant species.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Polyembryony and identification of Volkamerian lemon zygotic and nucellar seedlings using RAPD Poliembrionia e identificação de seedlings zigóticos e nucelares de limão volkameriano com RAPD

    Directory of Open Access Journals (Sweden)

    María Andrade-Rodríguez

    2004-06-01

    Full Text Available The objectives of this work were to evaluate the frequency of polyembryony, and to identify zygotic and nucellar seedlings of Citrus volkameriana using RAPD. Twenty-five polyembryonic and eight monoembryonic seeds were cultivated in vitrofor six months. DNA from seedlings was extracted and used in combination with five RAPD primers to identify zygotic or nucellar origin of the seedlings. Environmental conditions of the year affected significantly (POs objetivos deste trabalho foram avaliar a freqüência da poliembrionia e indentificar os seedlings zigóticos e nucelares de Citrus volkameriana usando RAPD. Cultivaram-se in vitro 25 sementes poliembriônicas e 8 monoembriônicas, por seis meses. Extraiu-se o DNA dos seedlings e usou-se em combinação com cinco primers RAPD para identificar a origem zigótica e nucelar das plântulas. Os resultados mostraram que as condições ambientais do ano afetaram significativamente (P<0,05 as características morfológicas dos frutos e o número de embriões por semente. Os índices de sementes poliembriônicas variaram nos três anos de avaliação (30,9%, 44,8% e 54,4%. As características morfológicas não se correlacionaram com a poliembrionia. A cultura in vitro possibilita que todos os embriões de cada semente cresçam, favorecendo os seedlings identificados como zigóticos. Nas sementes poliembriônicas e monoembriônicas, 25,9% e 87,5% dos seedlings, respectivamente, originaram-se sexualmente. Nem todos os seedlings zigóticos foram produzidos por embriões localizados no micrófilo das sementes poliembriônicas.

  1. Effects of pectinase clarification treatment on phenolic compounds of pummelo (Citrus grandis l. Osbeck) fruit juice.

    Science.gov (United States)

    Shah, Nor Nadiah Abdul Karim; Rahman, Russly Abdul; Shamsuddin, Rosnah; Adzahan, Noranizan Mohd

    2015-08-01

    The purpose of this study is to investigate the changes occured on phenolic compounds between two Malaysian varieties of pummelo fruit juice: Ledang (PO55) and Tambun (PO52) post-enzymatic clarification. The changes in polyphenols composition were monitored using High Performance Liquid Chromatography Diode Array Detection and Folin Ciocalteu's method. Clarification treatment of pummelo fruit juice with a commercial pectinase was optimized based on incubation temperature, time and enzyme concentration. Both varieties of pummelo fruit juice were treated with different optimized variables which produced the highest clarities with the least effect to the juice physical quality. Tambun variety was found to have significantly more total phenolic compounds (p fruit juices, where naringin and chlorogenic acid were the major contributor to the total phenolic content. Naringin, which gave out bitter aftertaste to the juice, was found to decrease, 1.6 and 0.59 % reduction in Ledang and Tambun respectively, post-enzymatic treatment. The decrease in naringin, albeit nominal, could be a potential benefit to the juice production in reducing the bitterness of the juice. Post-enzymatic analysis furthermore resulted in no significance differences (p fruit juice of various phenolic compounds, which can provide useful information for evaluating the authenticity and the health benefits from the juice.

  2. Effects of pectinase clarification treatment on phenolic compounds of pummelo (Citrus grandis l. Osbeck) fruit juice

    OpenAIRE

    Shah, Nor Nadiah Abdul Karim; Rahman, Russly Abdul; Shamsuddin, Rosnah; Adzahan, Noranizan Mohd

    2014-01-01

    The purpose of this study is to investigate the changes occured on phenolic compounds between two Malaysian varieties of pummelo fruit juice: Ledang (PO55) and Tambun (PO52) post-enzymatic clarification. The changes in polyphenols composition were monitored using High Performance Liquid Chromatography Diode Array Detection and Folin Ciocalteu’s method. Clarification treatment of pummelo fruit juice with a commercial pectinase was optimized based on incubation temperature, time and enzyme conc...

  3. A novel virus of the genus Cilevirus causing symptoms similar to citrus leprosis.

    Science.gov (United States)

    Roy, Avijit; Choudhary, Nandlal; Guillermo, Leon M; Shao, Jonathan; Govindarajulu, Ananthakrishnan; Achor, Diann; Wei, G; Picton, D D; Levy, L; Nakhla, M K; Hartung, John S; Brlansky, R H

    2013-05-01

    Citrus leprosis in Colombia was previously shown to be caused by cytoplasmic Citrus leprosis virus (CiLV-C). In 2011, enzyme-linked immunosorbent assay and reverse-transcription polymerase chain reaction (RT-PCR)-based diagnostic methods failed to identify CiLV-C from citrus samples with symptoms similar to citrus leprosis; however, virions similar to CiLV-C were observed in the cytoplasm of the symptomatic leaves by transmission electron microscopy. Furthermore, the causal organism was transmitted by the false spider mite, Brevipalpus phoenicis, to healthy citrus seedlings. A library of small RNAs was constructed from symptomatic leaves and used as the template for Illumina high-throughput parallel sequencing. The complete genome sequence and structure of a new bipartite RNA virus was determined. RNA1 (8,717 nucleotides [nt]) contained two open reading frames (ORFs). ORF1 encoded the replication module, consisting of five domains: namely, methyltransferase (MTR), cysteine protease-like, FtsJ-MTR, helicase (Hel), and RNA-dependent RNA polymerase (RdRp); whereas ORF2 encoded the putative coat protein. RNA2 (4,989 nt) contained five ORFs that encode the movement protein (MP) and four hypothetical proteins (p7, p15, p24, and p61). The structure of this virus genome resembled that of CiLV-C except that it contained a long 3' untranslated terminal region and an extra ORF (p7) in RNA2. Both the RNA1 and RNA2 of the new virus had only 58 and 50% nucleotide identities, respectively, with known CiLV-C sequences and, thus, it appears to be a novel virus infecting citrus. Phylogenetic analyses of the MTR, Hel, RdRp, and MP domains also indicated that the new virus was closely related to CiLV-C. We suggest that the virus be called Citrus leprosis virus cytoplasmic type 2 (CiLV-C2) and it should be unambiguously classified as a definitive member of the genus Cilevirus. A pair of CiLV-C2 genome-specific RT-PCR primers was designed and validated to detect its presence in citrus

  4. ECONOMIC EVALUATION OF Eucalyptus grandis PLANTATION FOR CELLULOSE PRODUCTION

    Directory of Open Access Journals (Sweden)

    Antonio Donizette de Oliveira

    2008-03-01

    Full Text Available The aims of this research were: to analyze the economic feasibility of planting eucalyptus for producing wood pulp,considering various site index and two spacings; to analyze the economic effects regarding the profitability of the forest activity indifferent distances from the industry and changes on discount rate, wood price, transportation costs, minimum profitable diameter oflogs and the length of the logs. A biometric model for making wood volume prognosis was developed, using data of a trial ofEucalyptus grandis stands 19 and 103 months old. The prognosis started at the age zero, considering logs of 2.5 and 6.0 m of lenghtand the minimum diameter varying from 4 to 10 cm, in intervals of 2 cm. Net Present Worth (NPW was used as the economic decisioncriterium, considering an infinite horizon. The main conclusions were: reducing the minimum profitable diameter and the length ofthe logs are good strategies to increase wood utilization and profit; plantations located in less productive lands are economicallyunfeasible; the cost of transportation has significant effect on the profitability of the forest activity and must be analyzed carefully atthe moment of defining the location of new plantations; small variations on wood sales price may cause big alterations on theprofitability of the forest activity, suggesting that the improvement of the wood quality together with other decisions that may increasewood price are alternatives that may render the plantations in less productive areas profitable.

  5. Response of Eucalyptus grandis trees to soil water deficits

    Energy Technology Data Exchange (ETDEWEB)

    Dye, P. J. [Commonwealth Scientific and Industrial Research, Division of Forest Science and Technology, Nelspruit (South Africa)

    1996-01-01

    Eucalyptus grandis trees subjected to soil drying at two field sites in the Mpumalanga province of South Africa were studied to determine the relation between transpiration rate and soil water availability. It was expected that by defining this relationship, modeling of the soil water balance could be used to predict the fraction of transpiration taking place at any given time. As part of the experimental procedure soil water recharge was prevented by plastic sheeting, thus allowing the roots in the soil to induce continuous progressive depletion of soil water. Measurements of predawn xylem pressure potential, leaf area index, growth and sap flow rates revealed only moderate drought stress; trees at both sites extracted water down to eight meters and more, below the surface. These results suggest that because of uncertainties about the depth of the root system, the soil water recharge mechanisms and other related factors, soil water balance studies are not useful in predicting the occurrence and severity of soil water deficits at these sites. 13 refs., 2 tabs., 8 figs.

  6. Effects of torrefaction on energy properties of Eucalyptus grandis wood

    Directory of Open Access Journals (Sweden)

    Thiago Oliveira Rodrigues

    2009-12-01

    Full Text Available Torrefaction is a thermal treatment that promotes homogenization and improvement of energy properties of biomass. This study aims to evaluate the effects of torrefaction on the main energy properties of Eucalyptus grandis wood. Wood was torrefied at three distinct temperatures (220°C, 250°C and 280°C and analyzed for gravimetric yield (ratio of dry wood mass to torrefied wood mass, bulk density (ratio of dry torrefied mass to dry torrefied volume, heating value (higher – HHV, lower – LHV and useful – UHV, energy density (ratio of heating value to bulk density and energy yield (product of gravimetric yield and ratio of HHV of torrefied wood to HHV of feedstock. The obtained results revealed significant differences for all properties being analyzed except for bulk density, which showed no statistical difference between the control and the treatment at 220°C. Temperature 250°C generated the best energy density as a function of the increase in heating value and the slight decrease in bulk density.

  7. Cassia grandis Linn. f. seed galactomannan: structural and crystallographical studies.

    Science.gov (United States)

    Joshi, Harsha; Kapoor, Virendra P

    2003-09-01

    Cassia grandis is a small or medium sized tree, found in abundance throughout India. The seeds contain about 50% endosperm gum and possess the characteristics of becoming a potential source of seed gum. The purified polysaccharide has been characterized as a pure galactomannan having a mannose-galactose ratio of 3.15; molecular weight (Mw) 80,200; polydispersity (Mw/Mn), 1.35 and intrinsic viscosity [eta], 848 mL/g. Methylation, periodate oxidation, Smith degradation and 13C NMR studies confirm that the polysaccharide has the basic structure of legume galactomannans consisting of a beta-(1-->4)-linked main mannan backbone to which galactose units are attached at O-6. The orthorhombic lattice constants of the hydrated gum are as follows: a=9.00, b=24.81, c=10.30 A. The crystallographic data establish that the probable space group symmetry of the unit cell is P2(1)2(1)2. The results are in contradiction to earlier reports (Indian J. Chem. 16B (1978) 966; J. Indian Chem. Soc. 55 (1978) 1216) in which a non-galactomannan polysaccharide structure has been assigned having a main chain of (1-->4)-linked galactose and mannose units in the molar ratio 6:3, where 50% of the galactose units branched with two galactose and one mannose through 1-->3 linkage.

  8. SPATIAL DEPENDENCE STUDY OF Eucalyptus grandis DENDROMETRIC CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    José Marcio de Mello

    2005-06-01

    Full Text Available The knowledge of spatial continuity structure of dendrometric characteristics is crucial in forest inventory, managementand planning. The inclusion of spatial continuity effect in inventory analysis provides stable and safe results that can be used in forestmanagement and planning. This paper evaluated the structure of spatial continuity of four dendrometric characteristics obtainedby two sampling procedures. Data were collected in 987 hectares of Eucalyptus grandis, located in the south of São Paulo State.Two sampling procedures were used, systematic grading and unencumbered systematic. For each plot from the two samples, thefollowing dendrometric characteristics were measured: volume, quadratic average diameter, basal area and average height of thedominant trees. For each one of these characteristics, anisotropic and isotropic semi variogrammes were built, in order toevaluate the spatial continuity structure. The semi variogrammes were built using the moment estimator method. The mainauthorized functions were adjusted to the experimental semi variogrammes, by The Minimum Square Method. The behavior of thespatial continuity was evaluated through the degree of spatial dependence and of the assigned semi variogrammes for the fourcharacteristics, in the appraised sampling methods, respectively. All appraised characteristics presented spatially structured,independently of the appraised sampling procedure. The continuity structure of the four characteristics was isotropic, i.e., thevariance among pairs of points depends on the separation vector h. Therefore, unidirectional semi variogrammes can be built forall appraised characteristics. The results suggest that, in forest inventory, the spatial component should be considered, i.e., plotsshould not be treated separately.

  9. 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...

  10. Drug: D06897 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D06897 Crude, Drug Citrus peel (non-JP); Kippi Essential oil Citrus tachibana [TAX:200544], Citrus... leiocarpa [TAX:237569], Cirus grandis [TAX:37334], Citrus unshiu [TAX:55188], Citrus reticul...ata [TAX:85571] Same as: E00194 Rutaceae (rue family) Citrus tachibana, Citrus leiocarpa, Cirus grandis fruit peel, or Citrus... unshiu, Citrus reticulata fruit peel; Standards for non-pharmac

  11. 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. ...

  12. 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...

  13. Eucalyptus grandis AND Eucalyptus dunnii USE FOR WOOD-CEMENT PANELS MANUFACTURING

    Directory of Open Access Journals (Sweden)

    Setsuo Iwakiri

    2008-03-01

    Full Text Available This research evaluated the potential use of Eucalyptus grandis and Eucalyptus dunnii wood for wood-cement panelsmanufacturing. The boards were manufactured at the density of 1,20 g/cm³, using portland cement as mineral bonding and woodfurnish without treatment, treated in cold water and hot water. The wood furnish of Pinus taeda was used as control. The resultsindicated that it is not necessary to treat E. grandis and E. dunni wood for wood-cement board manufacturing. In relation to woodspecies, the board manufactured with E. dunnii showed lower values of mechanical properties. However, boards manufactured of E.grandis wood showed satisfactory results in comparison to boards of P. taeda and the referenced values of BISON process and otherproducts cited in the pertnent literature, indicating the high potential for wood-cement board manufacture of this tree species.

  14. Effect of thermal modification on the physical properties of juvenile and mature woods of Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Fred Willians Calonego

    Full Text Available This study aimed to evaluate the effect of thermal treatment on the physical properties of juvenile and mature woods of Eucalyptus grandis. Boards were taken from 30-year-old E. grandis trees. The boards were thermally modified at 180 °C in the Laboratory of Wood Drying and Preservation at UNESP, Botucatu, Sao Paulo state, Brazil. The results showed that thermal modification caused: (1 decrease of 6.8% in the density at 0% equilibrium moisture content of mature wood; (2 significant decreases of 14.7% and 35.6% in the maximum volumetric swellings of juvenile and mature woods, respectively; (3 significant decreases of 13.7% and 21.3% in the equilibrium moisture content of juvenile and mature woods, respectively. The influence of thermal modification in juvenile wood was lower than in mature wood and caused greater uniformity in the physical variations between these types of wood in E. grandis.

  15. Transcriptome analysis in cotton boll weevil (Anthonomus grandis) and RNA interference in insect pests.

    Science.gov (United States)

    Firmino, Alexandre Augusto Pereira; Fonseca, Fernando Campos de Assis; de Macedo, Leonardo Lima Pepino; Coelho, Roberta Ramos; Antonino de Souza, José Dijair; Togawa, Roberto Coiti; Silva-Junior, Orzenil Bonfim; Pappas-Jr, Georgios Joannis; da Silva, Maria Cristina Mattar; Engler, Gilbert; Grossi-de-Sa, Maria Fatima

    2013-01-01

    Cotton plants are subjected to the attack of several insect pests. In Brazil, the cotton boll weevil, Anthonomus grandis, is the most important cotton pest. The use of insecticidal proteins and gene silencing by interference RNA (RNAi) as techniques for insect control are promising strategies, which has been applied in the last few years. For this insect, there are not much available molecular information on databases. Using 454-pyrosequencing methodology, the transcriptome of all developmental stages of the insect pest, A. grandis, was analyzed. The A. grandis transcriptome analysis resulted in more than 500.000 reads and a data set of high quality 20,841 contigs. After sequence assembly and annotation, around 10,600 contigs had at least one BLAST hit against NCBI non-redundant protein database and 65.7% was similar to Tribolium castaneum sequences. A comparison of A. grandis, Drosophila melanogaster and Bombyx mori protein families' data showed higher similarity to dipteran than to lepidopteran sequences. Several contigs of genes encoding proteins involved in RNAi mechanism were found. PAZ Domains sequences extracted from the transcriptome showed high similarity and conservation for the most important functional and structural motifs when compared to PAZ Domains from 5 species. Two SID-like contigs were phylogenetically analyzed and grouped with T. castaneum SID-like proteins. No RdRP gene was found. A contig matching chitin synthase 1 was mined from the transcriptome. dsRNA microinjection of a chitin synthase gene to A. grandis female adults resulted in normal oviposition of unviable eggs and malformed alive larvae that were unable to develop in artificial diet. This is the first study that characterizes the transcriptome of the coleopteran, A. grandis. A new and representative transcriptome database for this insect pest is now available. All data support the state of the art of RNAi mechanism in insects.

  16. Transcriptome analysis in cotton boll weevil (Anthonomus grandis and RNA interference in insect pests.

    Directory of Open Access Journals (Sweden)

    Alexandre Augusto Pereira Firmino

    Full Text Available Cotton plants are subjected to the attack of several insect pests. In Brazil, the cotton boll weevil, Anthonomus grandis, is the most important cotton pest. The use of insecticidal proteins and gene silencing by interference RNA (RNAi as techniques for insect control are promising strategies, which has been applied in the last few years. For this insect, there are not much available molecular information on databases. Using 454-pyrosequencing methodology, the transcriptome of all developmental stages of the insect pest, A. grandis, was analyzed. The A. grandis transcriptome analysis resulted in more than 500.000 reads and a data set of high quality 20,841 contigs. After sequence assembly and annotation, around 10,600 contigs had at least one BLAST hit against NCBI non-redundant protein database and 65.7% was similar to Tribolium castaneum sequences. A comparison of A. grandis, Drosophila melanogaster and Bombyx mori protein families' data showed higher similarity to dipteran than to lepidopteran sequences. Several contigs of genes encoding proteins involved in RNAi mechanism were found. PAZ Domains sequences extracted from the transcriptome showed high similarity and conservation for the most important functional and structural motifs when compared to PAZ Domains from 5 species. Two SID-like contigs were phylogenetically analyzed and grouped with T. castaneum SID-like proteins. No RdRP gene was found. A contig matching chitin synthase 1 was mined from the transcriptome. dsRNA microinjection of a chitin synthase gene to A. grandis female adults resulted in normal oviposition of unviable eggs and malformed alive larvae that were unable to develop in artificial diet. This is the first study that characterizes the transcriptome of the coleopteran, A. grandis. A new and representative transcriptome database for this insect pest is now available. All data support the state of the art of RNAi mechanism in insects.

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

    Directory of Open Access Journals (Sweden)

    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

  18. 尾巨桉纯林土壤化感效应的生物评价%Bioassay of Allelopathic Effects of Pure Forest Soil of Eucalyptus urophylla × E.grandis

    Institute of Scientific and Technical Information of China (English)

    郝建; 王凌晖; 秦武明

    2011-01-01

    用不同浓度的尾巨桉(Eucalyptus urophylla×E.grandis)纯林土壤水浸提液处理菜心(Brassica parachinensis)、白菜(B.pekineinsis)、水稻(Oryza sativa)、萝卜(Raphanus sativus)的种子和幼苗,综合评价尾巨桉纯林土壤的化感作用.结果表明,尾巨桉纯林土壤对所选作物有化感作用,浸提液浓度不同,其化感效应不同,受体植物不同,化感效应差别也较大,浓度越低化感作用越小,而随着溶液浓度的增大化感抑制作用逐渐增强.%Solutions of water extract of the soil of pure Eucalyptus urophylla × E. grandis forest were applied on the seeds and seedlings of Brassica parachinensis, B. pekinensis, Oryza sativa, and Raphanus sativus to comprehensively evaluate the allelopathic effects of the soil. Allelopathic effects of the soil to the selected crops were found, and exhibited concentration dependency. Differences in the degrees of allelopathy among different crops were also found.

  19. 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.

  20. 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.

  1. 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.

  2. 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. ...

  3. 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,...

  4. 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...

  5. 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...

  6. 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...

  7. Integration of Metabolomics and Subcellular Organelle Expression Microarray to Increase Understanding the Organic Acid Changes in Post-harvest Citrus Fruit

    Institute of Scientific and Technical Information of China (English)

    Xiaohua Sun; Zhaocheng Ma; Yunjiang Cheng; Xiuxin Deng; Andan Zhu; Shuzhen Liu; Ling Sheng; Qiaoli Ma; Li Zhang; Elsayed Mohamed Elsayed Nishawy; Yunliu Zeng; Juan Xu

    2013-01-01

    Citric acid plays an important role in fresh fruit flavor and its adaptability to post-harvest storage conditions. In order to explore organic acid regulatory mechanisms in post-harvest citrus fruit, systematic biological analyses were conducted on stored Hirado Buntan Pummelo (HBP; Citrus grandis) fruits. High-performance capillary electrophoresis, subcellular organelle expression microarray, real-time quantitative reverse transcription polymerase chain reaction, gas chromatography mass spectrometry (GC-MS), and conventional physiological and biochemical analyses were undertaken. The results showed that the concentration of organic acids in HBP underwent a regular fluctuation. GC-MS-based metabolic profiling indicated that succinic acid, g-aminobutyric acid (GABA), and glutamine contents increased, but 2-oxoglutaric acid content declined, which further confirmed that the GABA shunt may have some regulatory roles in organic acid catabolism processes. In addition, the concentration of organic acids was significantly correlated with senescence-related physiological processes, such as hydrogen peroxide content as well as superoxide dismutase and peroxidase activities, which showed that organic acids could be regarded as important parameters for measuring citrus fruit post-harvest senescence processes.

  8. Characterization of arbuscular mycorrhizal fungus communities of Aquilaria crassna and Tectona grandis roots and soils in Thailand plantations.

    Directory of Open Access Journals (Sweden)

    Amornrat Chaiyasen

    Full Text Available Aquilaria crassna Pierre ex Lec. and Tectona grandis Linn.f. are sources of resin-suffused agarwood and teak timber, respectively. This study investigated arbuscular mycorrhizal (AM fungus community structure in roots and rhizosphere soils of A. crassna and T. grandis from plantations in Thailand to understand whether AM fungal communities present in roots and rhizosphere soils vary with host plant species and study sites. Terminal restriction fragment length polymorphism complemented with clone libraries revealed that AM fungal community composition in A. crassna and T. grandis were similar. A total of 38 distinct terminal restriction fragments (TRFs were found, 31 of which were shared between A. crassna and T. grandis. AM fungal communities in T. grandis samples from different sites were similar, as were those in A. crassna. The estimated average minimum numbers of AM fungal taxa per sample in roots and soils of T. grandis were at least 1.89 vs. 2.55, respectively, and those of A. crassna were 2.85 vs. 2.33 respectively. The TRFs were attributed to Claroideoglomeraceae, Diversisporaceae, Gigasporaceae and Glomeraceae. The Glomeraceae were found to be common in all study sites. Specific AM taxa in roots and soils of T. grandis and A. crassna were not affected by host plant species and sample source (root vs. soil but affected by collecting site. Future inoculum production and utilization efforts can be directed toward the identified symbiotic associates of these valuable tree species to enhance reforestation efforts.

  9. Effect of drought stress on mineral nutrient contents in leaves of sdeedling plant of C. tangerina Hort., C. sinensis Osbeck and C. grandis Osbeck%干旱胁迫对实生红橘、甜橙和柚叶中营养元素含量的影响

    Institute of Scientific and Technical Information of China (English)

    马文涛; 樊卫国

    2007-01-01

    以红橘(Citrus tangerina Hort.)、甜橙(Citrus sinensis Osbeck)、柚(Citrus grandis Osbeck)实生苗为材料,采用模拟降雨控水长期干旱胁迫的方法,研究了降水量400和800 mm的干旱胁迫对3种柑橘实生苗叶片的N、P、K、Ca、Mg、Fe、Zn、Cu、Mn、B元素含量的影响.结果表明:干旱胁迫降低了实生甜橙、红橘和柚的叶片中N、P、K、Ca、Mg、Fe、Cu、B元素的含量,增加了叶中Mn元素的含量;实生红橘和柚叶中的Zn含量在降水量400 mm的干旱胁迫下显著降低,而同样的干旱胁迫条件下,实生甜橙叶中的Zn含量极显著地增加了.干旱胁迫降低实生甜橙和红橘叶中N、Ca、Mg、Fe、Cu、B元素含量的作用相对较大.

  10. 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...

  11. Sex pheromone components and control of the citrus pock caterpillar, Prays endocarpa, found in the Mekong Delta of Vietnam.

    Science.gov (United States)

    Vang, Le Van; Do, Nguyen Duc; An, Le Ky; Son, Pham Kim; Ando, Tetsu

    2011-01-01

    The citrus pock caterpillar, Prays endocarpa (Yponomeutidae; Praydinae), is a pest of pomelo (Citrus grandis L.) in Vietnam. Gas chromatography-mass spectrometry analyses of pheromone gland extracts from female moths identified three monoenyl compounds, (Z)-7-tetradecenal (Z7-14:Ald), (Z)-7-tetradecenyl acetate (tentatively identified, Z7-14:OAc), and (Z)-7-tetradecen-1-ol (Z7-14:OH), in a ratio of about 10:3:10. In the field, traps baited with synthetic Z7-14:Ald (0.5 mg) caught male P. endocarpa. The other two compounds, either alone or when added to Z7-14:Ald, did not elicit increases in trap catch (relative to the appropriate treatment). Synthetic Z7-14:Ald was used to monitor and control this species in pomelo orchards in Vinh Long Province. Monitoring revealed that adults were present throughout the year with discernible peaks in December, March, and April. A mass-trapping trial, using 20 traps in a 0.1 ha pomelo orchard, effectively suppressed fruit damage to levels similar to that achieved by an insecticide (Karate 2.5EC). Mating disruption trials, using polyethylene-tube dispensers, each filled with 80 mg of Z7-14:Ald at a rate of 200 or 400 dispensers/ha, also controlled damage by this pest to levels below that achieved by an insecticide treatment. This work demonstrates the potential for pheromone-based control of this pest in Vietnam.

  12. Chemical components of cold pressed kernel oils from different Torreya grandis cultivars.

    Science.gov (United States)

    He, Zhiyong; Zhu, Haidong; Li, Wangling; Zeng, Maomao; Wu, Shengfang; Chen, Shangwei; Qin, Fang; Chen, Jie

    2016-10-15

    The chemical compositions of cold pressed kernel oils of seven Torreya grandis cultivars from China were analyzed in this study. The contents of the chemical components of T. grandis kernels and kernel oils varied to different extents with the cultivar. The T. grandis kernels contained relatively high oil and protein content (45.80-53.16% and 10.34-14.29%, respectively). The kernel oils were rich in unsaturated fatty acids including linoleic (39.39-47.77%), oleic (30.47-37.54%) and eicosatrienoic acid (6.78-8.37%). The kernel oils contained some abundant bioactive substances such as tocopherols (0.64-1.77mg/g) consisting of α-, β-, γ- and δ-isomers; sterols including β-sitosterol (0.90-1.29mg/g), campesterol (0.06-0.32mg/g) and stigmasterol (0.04-0.18mg/g) in addition to polyphenols (9.22-22.16μgGAE/g). The results revealed that the T. grandis kernel oils possessed the potentially important nutrition and health benefits and could be used as oils in the human diet or functional ingredients in the food industry.

  13. A Multivariate Study on Genetic Variation in Teak (Tectona grandis (L.))

    DEFF Research Database (Denmark)

    Kjær, Erik Dahl; Siegismund, Hans Redlef; Suangtho, V.

    1996-01-01

    Genetic differentiation between populations of teak (Tectona grandis (L.)) was examined in 9 quantitative characters and 10 allozyme loci. Large differences between populations were revealed in the quantitative traits. Regional patterns were revealed by multivariate analysis of the data, but ther...

  14. 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.

  15. 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...

  16. Solarization of nursery soil induces production of fruit bodies of mushrooms and enhances growth of tropical forest tree seedlings

    Directory of Open Access Journals (Sweden)

    R.K. Verma

    2010-12-01

    Full Text Available The aim of this work was to find out the effect of soil solarization on microbial population and its effect on growth of two species of tropical forest trees. For this purpose, solar heating of nursery seedbeds (1 x 5m was done during April- May 2009 for one month, by application of a thin clear sheet of polyethylene. The top soil (5 inches consists of a mix of loam soil, sand and farm yard manure in 2:1:0.5 ratios (v/v. Temperature variations were recorded daily for a period of one month, at 2 depths, (5 cm and 10 cm. Maximum differences in temperature between solar treatment and control was recorded as high as 12.1° C at 5 cm and 9.1° C at 10 cm depth. After one month, population of Aspergillus, Fusarium, Penicillium, Rhizopus and nematodes were completely eliminated from upper 5 cm depth, although population of AM fungi, bacteria and Trichoderma were reduced, but not completely eliminated. Seedlings of Gmelina arborea Roxb. and Tectona grandis Linn.f. were raised through seeds on treated and control beds. After three months, the production of fruit bodies of mushrooms, namely Amanita populiphila Tullos & E. Moses, Lepiota longicauda Henn. and Scleroderma sp. were observed. It was noticed that these mushrooms only appeared on treated soil with white mycelial growth in rhizosphere under fruit bodies. Lepiota longicauda produced the maximum number of fruit bodies on teak seedbeds followed by Scleroderma sp. on G. arborea seedbeds. Due to solar heating there was 23.9% increase in plant height and 22.1% increase in collar diameter of G. arborea seedlings, where as 17.4% increase in plant height and 9.8% increase in collar diameter in case of T. grandis, as compared to control seedlings.

  17. 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.

  18. Signaling pathways in a Citrus EST database

    Directory of Open Access Journals (Sweden)

    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.

  19. Períodos de interferência de trapoeraba (Commelina benghalensis Hort. no crescimento inicial de eucalipto (Eucalyptus grandis W. Hill ex Maiden Periods of Commelina benghalensis interference in the initial growth of Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Augusto Guerreiro Fontoura Costa

    2004-08-01

    Full Text Available A trapoeraba (Commelina benghalensis, em razão do uso contínuo de mesmos herbicidas e outros métodos de controle, vem se constituindo numa das plantas mais freqüentes em eucaliptais do Estado de São Paulo. Por isso, objetivou-se neste trabalho avaliar os efeitos de períodos de controle e convivência dessa planta daninha sobre o desenvolvimento inicial de mudas de Eucalyptus grandis, transplantadas no inverno e no verão. Uma única muda de eucalipto foi transplantada em caixa de cimento-amianto e submetida a períodos crescentes de convivência e de controle da trapoeraba (0, 20, 40, 60 e 80 dias no sujo e no limpo, respectivamente, sendo a densidade de plantas de trapoeraba de 4 plantas.m-2 (nas condições de inverno e verão. Conduziu-se o ensaio por um período de 100 dias após o transplante (DAT, e o delineamento experimental adotado foi o de blocos casualizados, com 10 tratamentos com quatro repetições. Pelos resultados da altura das plantas, diâmetro do caule, biomassa seca e área foliar, verificou-se que o período anterior à interferência (PAI, o total de prevenção à interferência (PTPI e o período crítico de prevenção à interferência (PCPI foram de 20, 60 e 20 a 60 DAT, respectivamente, no inverno. Em condições de verão, o PTPI foi menor que o PAI (10 e 40 DAT, respectivamente. Assim, não foi possível estabelecer o PCPI nessas condições.Commelina benghalensis is becomming the predominant weed invading eucalypts plantations in the State of São Paulo due to the continual use of herbicides and other control methods applied. Considering this, the objective of this work was to evaluate the effect of presence and control periods of Commelina benghalensis on Eucalyptus grandis initial growth, grew in winter and summer. A single eucalypt seedling was planted in a cement box and submitted to increasing periods of presence and control of Commelina benghalensis (0, 20, 40, 60 e 80 days in competition or not

  20. Morphological parameters and genetic diversity of progenies from seed production areas and unimproved stands of teak (Tectona grandis L.f.) in India

    Institute of Scientific and Technical Information of China (English)

    N. Lyngdoh; Geeta Joshi; G. Ravikanth; R. Vasudeva; R. Uma Shaanker

    2013-01-01

    We compared morphological and genetic attributes of prog-eny obtained from three seed production areas (SPAs) and three corre-sponding unimproved stands (UIS) of teak (Tectona grandis L.f) at three broad teak growing regions in the state of Karnataka, India. In general, seed morphological parameters such as seed weight, seed size and seed emptiness were significantly superior in SPAs compared to UISs. Seed germination percentage was also higher in seeds from SPAs. Seedling performance measured at two monthly intervals for six months was ob-served to be superior in SPAs at two of the three regions compared. Although the genetic diversity of progeny of SPAs was lower than UIS at all regions, the values were moderately high. Germination percent was positively correlated with fruit weight and kernel weight per seed, while diversity indices were negatively correlated with fruit weight, fruit di-ameter and kernel weight per seed. SPAs proved important as a source of moderately improved planting material with no severe threat to the ge-netic diversity of future plantations.

  1. Effects of Bentonite, Charcoal and Corncob for Soil Improvement and Growth Characteristics of Teak Seedling Planted on Acrisols in Northeast Thailand

    Directory of Open Access Journals (Sweden)

    Masazumi Kayama

    2016-02-01

    Full Text Available When teak (Tectona grandis L. f. is planted on acrisols in Northeast Thailand, its growth is suppressed by low pH, infertility, and low water holding capacity. To examine materials capable of increasing water holding capacity in soil and improving teak growth, we conducted an experiment with teak seedlings. We selected bentonite, charcoal, and corncob and added these materials at a rate of 4% to sandy soil from northeast Thailand. Teak seedlings were potted on these soils and raised from July 2013 to July 2014. We compared growth, photosynthetic rates, leaf water potential, and concentrations of elements in plant organs among bentonite, charcoal, corncob, and no addition (control treatments. Water content in the soils was increased for the bentonite and charcoal treatments. Teak seedlings potted in these two conditions did not suffer from drought stress. Comparing the growth traits of the teak seedlings, the charcoal treatment produced larger root growth and promoted the uptake of phosphorus and potassium, whereas the bentonite treatment did not show positive effects on growth or nutrient acquisition. In contrast, the corncob treatment decreased water content in the soil, and teak seedling growth was suppressed. We concluded that charcoal was a useful material to improve teak growth in sandy soils.

  2. Prey preference and host suitability of the predatory and parasitoid carabid beetle, Lebia grandis, for several species of Leptinotarsa beetles

    OpenAIRE

    Donald C. Weber; Rowley, Daniel L.; Greenstone, Matthew H.; Athanas, Michael M.

    2006-01-01

    Lebia grandis (Coleoptera: Carabidae), recorded as a parasitoid only on Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae), is capable of parasitizing the false potato beetle, L. juncta, and also L. haldemani. Historical records show that L. decemlineata, while the only recorded host, was not present in much of the original range of L. grandis, and may not have been its host prior to its expansion into eastern North America, where L. juncta is endemic. Our laborator...

  3. Impact of decomposing Cinnamomum septentrionale leaf litter on the growth of Eucalyptus grandis saplings.

    Science.gov (United States)

    Huang, Weiwei; Hu, Tingxing; Chen, Hong; Wang, Qian; Hu, Hongling; Tu, Lihua; Jing, Liao

    2013-09-01

    A pot experiment was performed to study the impact of decomposing Cinnamomum septentrionale leaf litter on the growth of Eucalyptus grandis saplings. The experimental design scheme was 0 (CK), 40 (A1), 80 (A2) and 120 g pot(-1) (A3) of E. grandis leaves, and changes in the volatile oil chemical composition during litter decomposition were assessed in the present study. The results showed that C. septentrionale leaf litter inhibited the growth of E. grandis saplings, as determined by the height, basal diameter and chlorophyll content, after 69 d (T1). Five months after transplantation (T2), the height growth rate of the E. grandis saplings increased and then gradually reduced (A1: 40 g pot(-1) > A2: 80 g pot(-1) > A3: 120 g pot(-1) > CK: 0 g pot(-1)). After eleven months (T3), the variations in the height and basal diameter were the same as observed at T2, and the inhibition on leaf, branch, root and stem biomass increased with increasing leaf litter content. Gas chromatography-mass spectrometry (GC-MS) was used to identify the volatile compound composition. The results indicated that the C. septentrionale original leaf litter (S1) contained thirty-one volatile compounds, but the treated leaf litter S2 (which was mixed with soil for eleven months to simultaneously plant E. grandis saplings) only possessed fourteen volatile compounds, releasing many secondary metabolites in the soil during decomposition. Most of the volatile compounds were alcohols, monoterpenoids, sesquiterpenes, alkanes, alkene, esters and ketones. Most of the allelochemicals of C. septentrionale might be released during the initial decomposing process, inhibiting the growth of other plants, whereas some nutrients might be released later, promoting the height growth of plants. In conclusion, decomposing C. septentrionale leaf litter release of many allelochemicals in the soil that significantly inhibit the growth of E. grandis.

  4. 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...

  5. 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

  6. 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.

  7. Temporal dynamics of the response to Al stress in Eucalyptus grandis × Eucalyptus camaldulensis

    Directory of Open Access Journals (Sweden)

    Berenice K. de Alcântara

    2015-06-01

    Full Text Available Lipid peroxidation and root elongation of Eucalyptus grandis × Eucalyptus camaldulensis were studied under stress conditions in response to aluminum (Al, a metal known to limit agricultural productivity in acidic soils primarily due to reduced root elongation. In Brazil, the Grancam 1277 hybrid (E. grandis × E. camaldulensis has been planted in the "Cerrado", a region of the country with a wide occurrence of acidic soils. The present study demonstrated that the hybrid exhibited root growth reduction and increased levels of lipid peroxidation after 24h of treatment with 100 µM of Al, which was followed by a reduction in lipid peroxidation levels and the recovery of root elongation after 48h of Al exposure, suggesting a rapid response to the early stressful conditions induced by Al. The understanding of the temporal dynamics of Al tolerance may be useful for selecting more tolerant genotypes and for identifying genes of interest for applications in bioengineering.

  8. Cloning and structural analysis of a haemocyanin from the Stonefly Perla grandis.

    Science.gov (United States)

    Fochetti, Romolo; Belardinelli, Mariacristina; Guerra, Laura; Buonocore, Francesco; Fausto, Anna Maria; Caporale, Carlo

    2006-12-01

    We characterized two subunits of a putative haemocyanin from the stonefly species Perla grandis. In particular, we cloned and sequenced the corresponding cDNAs and studied their expression in different insect stages. Moreover, using the deduced amino acid sequences, homology studies were performed both on their primary and tertiary structures. 3-D molecular modelling data showed that the residues involved in the oxygen transport and subunits contacts were located in spatial positions preserving the functionality of the molecule. Despite it was paradigmatically affirmed that insects do not have respiratory proteins, our data suggest that the haemocyanin could be involved in the respiratory mechanisms of P. grandis. As far as we know, this is the first haemocyanin 3-D structure described and analyzed in insects.

  9. Assessment of the antidiabetic potential of Cassia grandis using an in vivo model

    Directory of Open Access Journals (Sweden)

    Sandesh R Lodha

    2010-01-01

    Full Text Available The aqueous and ethanolic extracts of C. grandis (Family: Leguminosae were evaluated for antidiabetic activity by a glucose tolerance test, in normal rats and alloxan-induced diabetic rats. The aqueous and ethanolic extracts showed that they significantly lowered the blood glucose levels to normal in the glucose tolerance test. In alloxan-induced diabetic rats the maximum reduction in blood glucose was observed after three hours, at a dose level of 150 mg/kg of body weight. The percentage of protection given by the aqueous and ethanolic extracts was 32.72 and 46.42%, respectively. In the long-term treatment of alloxan-induced diabetic rats, the degree of protection was determined by measuring the blood glucose, cholesterol, and triglycerides on the tenth day. Both the extracts showed a significant antidiabetic activity comparable to that of glibenclamide. These results showed that the Cassia grandis possessed significant antidiabetic activity.

  10. Modification of static bending strength properties of Eucalyptus grandis heat-treated wood

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Gonzalez de Cademartori

    2012-12-01

    Full Text Available The present study describes the effect of thermal rectification on physical and mechanical properties of Eucalyptus grandis wood at different levels of temperature and time. Samples of Eucalyptus grandis wood (10 × 10 × 200 mm were heat-treated at 180, 200, 220 and 240 °C during 4 and 8 hours. The mechanical properties of heat-treated and untreated samples were determined by static bending tests. The physical properties were determined by weight loss and swelling tests. The results showed that modulus of elasticity, modulus of rupture, weight loss, volumetric swelling and linear swelling were affected significantly by the thermal rectification. However, the length of exposure influenced just weight loss, while the temperature influenced all the studied properties of heat-treated wood. More significant modifications with treatments at a temperature of 200 °C or higher were found in the properties of heat-treated wood.

  11. 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...

  12. 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

  13. 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...

  14. 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

  15. 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

  16. 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.

  17. The oropharyngeal morphology in the semiaquatic giant Asian pond turtle, Heosemys grandis, and its evolutionary implications.

    Directory of Open Access Journals (Sweden)

    Monika Lintner

    Full Text Available The oropharynx as a functional entity plays a fundamental role in feeding. Transitions from aquatic to terrestrial lifestyles in vertebrates demanded major changes of the oropharynx for the required adaptations to a different feeding environment. Extant turtles evolved terrestrial feeding modes in three families (testudinids, emydids, geoemydids-independently from other amniotes-and are therefore important model organisms to reconstruct morpho-functional changes behind aquatic-terrestrial transitions. In this study we hypothesized that the oropharyngeal morphology in semiaquatic turtles of the geoemydid family shows parallels to testudinids, the only purely terrestrial extant lineage. We provide an in-depth description of the oropharynx in the semiaquatic geoemydid Heosemys grandis by using a combination of micro computed tomography (micro-CT and subsequent digital in situ 3-D reconstruction, scanning electron microscopy (SEM, and histology. We show that H. grandis has a large tongue with rough papillose surface and well-developed lingual muscles. The attachment sites of the lingual muscles on the hyolingual skeleton and their courses within the tongue are nearly identical with testudinids. The hyolingual skeleton itself is mainly cartilaginous and shows distinct-but compared to testudinids rather small-anterior extensions of the hyoid body and hypoglossum. Oral glands are well developed in H. grandis but are smaller and simpler than in testudinids. Similarly, oropharyngeal keratinization was minimal and found only in the anterior palate, regions close to the beak, and tongue tip. We conclude that H. grandis shows distinct oropharyngeal morpho-functional adaptations for a terrestrial lifestyle but still retains characters typical for aquatic forms. This makes this species an important example showing the oropharyngeal adaptations behind aquatic-terrestrial transitions in turtles.

  18. Growth Process of Eucalyptus urophylla × E.grandis Stand Based on Logistic Equation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Eucalyptus is the most valuable cultivated forest genus in the tropical and subtropical areas nowadays. It has been a challenge for foresters to model growth due to the genetic variations, management regimes, and multiple products generated from the plantations. In this paper, Logistic equation was used to study the stock growth process of E. urophylla × E. grandis plantation at age of 14 with 6 spacing treatments. And the biological interpretation of the parameters of Logistic equation was analyzed. The re...

  19. A Newly Identified Passive Hyperaccumulator Eucalyptus grandis × E. urophylla under Manganese Stress.

    Directory of Open Access Journals (Sweden)

    Qingqing Xie

    Full Text Available Manganese (Mn is an essential micronutrient needed for plant growth and development, but can be toxic to plants in excess amounts. However, some plant species have detoxification mechanisms that allow them to accumulate Mn to levels that are normally toxic, a phenomenon known as hyperaccumulation. These species are excellent candidates for developing a cost-effective remediation strategy for Mn-polluted soils. In this study, we identified a new passive Mn-hyperaccumulator Eucalyptus grandis × E. urophylla during a field survey in southern China in July 2010. This hybrid can accumulate as much as 13,549 mg/kg DW Mn in its leaves. Our results from Scanning Electron Microscope (SEM X-ray microanalysis indicate that Mn is distributed in the entire leaf and stem cross-section, especially in photosynthetic palisade, spongy mesophyll tissue, and stem xylem vessels. Results from size-exclusion chromatography coupled with ICP-MS (Inductively coupled plasma mass spectrometry lead us to speculate that Mn associates with relatively high molecular weight proteins and low molecular weight organic acids, including tartaric acid, to avoid Mn toxicity. Our results provide experimental evidence that both proteins and organic acids play important roles in Mn detoxification in Eucalyptus grandis × E. urophylla. The key characteristics of Eucalyptus grandis × E. urophylla are an increased Mn translocation facilitated by transpiration through the xylem to the leaves and further distribution throughout the leaf tissues. Moreover, the Mn-speciation profile obtained for the first time in different cellular organelles of Eucalyptus grandis × E. urophylla suggested that different organelles have differential accumulating abilities and unique mechanisms for Mn-detoxification.

  20. A Newly Identified Passive Hyperaccumulator Eucalyptus grandis × E. urophylla under Manganese Stress.

    Science.gov (United States)

    Xie, Qingqing; Li, Zhenji; Yang, Limin; Lv, Jing; Jobe, Timothy O; Wang, Qiuquan

    2015-01-01

    Manganese (Mn) is an essential micronutrient needed for plant growth and development, but can be toxic to plants in excess amounts. However, some plant species have detoxification mechanisms that allow them to accumulate Mn to levels that are normally toxic, a phenomenon known as hyperaccumulation. These species are excellent candidates for developing a cost-effective remediation strategy for Mn-polluted soils. In this study, we identified a new passive Mn-hyperaccumulator Eucalyptus grandis × E. urophylla during a field survey in southern China in July 2010. This hybrid can accumulate as much as 13,549 mg/kg DW Mn in its leaves. Our results from Scanning Electron Microscope (SEM) X-ray microanalysis indicate that Mn is distributed in the entire leaf and stem cross-section, especially in photosynthetic palisade, spongy mesophyll tissue, and stem xylem vessels. Results from size-exclusion chromatography coupled with ICP-MS (Inductively coupled plasma mass spectrometry) lead us to speculate that Mn associates with relatively high molecular weight proteins and low molecular weight organic acids, including tartaric acid, to avoid Mn toxicity. Our results provide experimental evidence that both proteins and organic acids play important roles in Mn detoxification in Eucalyptus grandis × E. urophylla. The key characteristics of Eucalyptus grandis × E. urophylla are an increased Mn translocation facilitated by transpiration through the xylem to the leaves and further distribution throughout the leaf tissues. Moreover, the Mn-speciation profile obtained for the first time in different cellular organelles of Eucalyptus grandis × E. urophylla suggested that different organelles have differential accumulating abilities and unique mechanisms for Mn-detoxification.

  1. Plant regeneration from protoplast of Brazilian citrus cultivars

    Directory of Open Access Journals (Sweden)

    GLORIA FERNANDA JANUZZI MENDES DA

    2000-01-01

    Full Text Available A procedure is described to regenerate plants from protoplasts of Brazilian citrus cultivars, after isolation, fusion and culture. Protoplasts were isolated from embryogenic cell suspension cultures and from leaf mesophyll of seedlings germinated in vitro. The enzyme solution for protoplast isolation was composed of mannitol (0.7 M, CaCl2 (24.5 mM, NaH2PO4 (0.92 mM, MES (6.15 mM, cellulase (Onozuka RS - Yakult, 1%, macerase (Onozuka R10 - Yakult, 1% and pectolyase Y-23 (Seishin, 0.2%. Protoplast culture in liquid medium after chemical fusion lead to the formation of callus colonies further adapted to solid medium. Somatic embryo formation occurred spontaneously after two subcultures, on modified MT medium supplemented with 500 mg/L of malt extract. Well defined embryos were germinated in modified MT medium with addition of GA3 (2.0 muM and malt extract (500 mg/L. Plant regeneration was also achieved by adventitious shoots obtained through direct organogenesis of not well defined embryos in modified MT medium with addition of malt extract (500 mg/L, BAP (1.32 muM, NAA (1.07 muM and coconut water (10 mL/L. Plantlets were transferred to root medium. Rooted plants were transferred to a greenhouse for further adaptation and development.

  2. MANEJO DO SOLO E CRESCIMENTO INICIAL DE Eucalyptus grandis Hill ex Maiden EM ARGISSOLO

    Directory of Open Access Journals (Sweden)

    Juliana Prevedello

    2013-01-01

    Full Text Available The forest species cultivation with rapid growth in Brazil has increased, mainly due to the diverse use of its wood and climate adaptation. The cultivation with minimum tillage in the forest sector stands out a way to increase productivity, combined with the maintenance of biodiversity and soil conservation. This study was conducted at the experimental area of State Foundation for Agricultural Research - Research Center for Forestry in Santa Maria - RS, with aimed to evaluate the effect of the soil tillage methods on soil physical properties and on initial development of Eucalyptus grandis, in a sandy loam Typic Hapludalf. Four soil management practices were compared: no-tillage; chisel tillage; chisel tillage plus harrowing and; rotary tillage (rotary tiller, installed in a randomized block design with three replications. The soil under no-tillage conditioned lower initial growth of eucalyptus due higher soil penetration resistance and bulk density, when compared with treatments with mobilization. The root distribution analysis in soil, despite being a qualitative method, was effective in demonstrating the effect of soil tillage for the Eucalyptus grandis plantation. The soil tillage with mobilization resulted in a higher initial growth of Eucalyptus grandis. The chisel tillage effects in the soil physical properties persisted after one year of soil tillage.

  3. Supercritical water gasification of Eucalyptus grandis and related pyrolysis char: Effect of feedstock composition.

    Science.gov (United States)

    Louw, Jeanne; Schwarz, Cara E; Burger, Andries J

    2016-09-01

    Eucalyptus grandis (E. grandis) wood and char products derived from pyrolysis of E. grandis wood, were gasified in supercritical water at 450°C - with and without the use of a homogeneous (K2CO3) and heterogeneous (Ni/Al2O3-SiO2) catalyst. Gas yields and gasification efficiencies were measured experimentally and compared to calculated thermodynamic equilibrium values, specifically considering the effects of the O/C ratio and volatile matter content of the feed material. Thermodynamically, feed material with lower O/C ratios (0.22) typically resulted in higher CH4 yields (30mol/kgfeed,dry) and gasification efficiencies (188%). However, experimentally, feed material with lower O/C ratios and lower volatile matter resulted in the lowest CH4 yields and gasification efficiencies. Furthermore, a linear relationship between the carbon efficiency (CE) and both the volatile matter content and O/C ratio of the feed material was found to hold true in both catalytic and non-catalytic experiments.

  4. Permanent draft genome sequence of the gliding predator Saprospira grandis strain Sa g1 (= HR1)

    Energy Technology Data Exchange (ETDEWEB)

    Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Chertkov, Olga [Los Alamos National Laboratory (LANL); Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Nolan, Matt [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Tice, Hope [U.S. Department of Energy, Joint Genome Institute; Glavina Del Rio, Tijana [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Han, Cliff [Los Alamos National Laboratory (LANL); Tapia, Roxanne [Los Alamos National Laboratory (LANL); Bruce, David [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Huntemann, Marcel [U.S. Department of Energy, Joint Genome Institute; Liolios, Konstantinos [U.S. Department of Energy, Joint Genome Institute; Pagani, Ioanna [U.S. Department of Energy, Joint Genome Institute; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Mikhailova, Natalia [U.S. Department of Energy, Joint Genome Institute; Pati, Amrita [U.S. Department of Energy, Joint Genome Institute; Chen, Amy [U.S. Department of Energy, Joint Genome Institute; Palaniappan, Krishna [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Brambilla, Evelyne-Marie [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Rohde, Manfred [HZI - Helmholtz Centre for Infection Research, Braunschweig, Germany; Spring, Stefan [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Bristow, James [U.S. Department of Energy, Joint Genome Institute; Eisen, Jonathan [U.S. Department of Energy, Joint Genome Institute; Markowitz, Victor [U.S. Department of Energy, Joint Genome Institute; Hugenholtz, Philip [U.S. Department of Energy, Joint Genome Institute; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute

    2012-01-01

    Saprospira grandis Gross et al. 1911 is a member of the Saprospiraceae, a family in the class 'Sphingobacteria' that remains poorly characterized at the genomic level. The species is known for preying on other marine bacteria via 'ixotrophy'. S. grandis strain Sa g1 was isolated from decaying crab carapace in France and was selected for genome sequencing because of its isolated location in the tree of life. Only one type strain genome has been published so far from the Saprospiraceae, while the sequence of strain Sa g1 represents the second genome to be published from a non-type strain of S. grandis. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,495,250 bp long Improved-High-Quality draft of the genome with its 3,536 protein-coding and 62 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  5. Evaluation of anti-inflammatory and analgesic potential of methanol extract of Tectona grandis flowers

    Institute of Scientific and Technical Information of China (English)

    Ramachandran S; Rajini kanth B; Rajasekaran A; Manisenthil Kumar KT

    2011-01-01

    Objective:To evaluate anti-inflammatory and analgesic activity of methanol extract of Tectona grandis (T. grandis) flowers (METGF) in animal models to support its traditional use. Methods:Acute toxicity study was performed to determine the toxicity level of METGF in mice and rats. Carrageenan (1%w/w) was administered and inflammation was induced in sub-plantar region of rat paw. Analgesia was induced by intraperitoneal injection of 0.6%v/v acetic acid in mice to assess peripheral analgesic action of METGF. Also, hot-plate was used to induce pain in mice to evaluate central analgesic action of METGF. Results: Oral administration of METGF in rat and mice did not produce any toxicity at 2 000 mg/kg dose level. In carrageenan induced inflammation, administration of METGF (100 and 200 mg/kg) as well as indomethacin (10 mg/kg) reduced rat paw edema significantly at 3, 4 and 5 h. Both the doses of METGF showed significant inhibition in acetic acid induced writhing responses. In thermally induced analgesia models, administration of METG at dose of 100 and 200 mg/kg significantly increased reaction time compared to control animals. The preliminary phytochemical analysis revealed the presence of phenolic compounds and tannins in METGF. Conclusions: Present study, for the first time, confirms the anti-inflammatory and analgesic action of METGF and it supports the traditional use of T. grandis flowers.

  6. EFFECT OF FERTILIZATION ON MECHANICAL PROPERTIES OF THE WOOD OF Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Israel Luiz de Lima

    2011-09-01

    Full Text Available The effect of the fertilization in the amount and quality of the produced wood is one of the questions to be considered in the research of the Eucalyptus grandis. The present work aimed to evaluate the fertilization effect in the mechanical properties of Eucalyptus grandis. The population of Eucalyptus grandis was 21 years old and was managed under the system of selective thinning, with application of fertilizers. The factors used in this study were: presence or absence of fertilizers, two positions of log and five radial positions. The influences of the factors and of their combinations were evaluated regarding to compression strength, shear strength, modulus of rupture and modulus of elasticity in static banding. The compressive strength and the modulus of elasticity had been influenced by the factors: fertilizer and radial positions of the log. There was also an increase in the direction of the pith-bark in all studied properties. A good positive relationship was found to exist among the compression strength, the shear, the modulus of rupture and the modulus of elasticity with radial position.

  7. EFEITO DO COBRE NA POPULAÇÃO DE BACTÉRIAS E FUNGOS DO SOLO, NA ASSOCIAÇÃO MICORRÍZICA E NO CULTIVO DE MUDAS DE Eucalyptus grandis W. Hill ex Maiden, Pinus elliottii Engelm E Peltophorum dubium (Sprengel Tauber

    Directory of Open Access Journals (Sweden)

    Zaida Inês Antoniolli

    2010-01-01

    Full Text Available Copper is a heavy metal that can have toxic effects on microorganisms and plants. Ectomycorrhizal fungi are able to protect the plant from heavy metal toxicity, but the presence of certain metal concentrations can inhibit the growth of this fungus, damage the mycorrhizal symbiosis and also altering the development of the plants. The aim of this study was to evaluate the effect of copper on soil bacteria and fungus population, as well as the effects on the ectomycorrhizal association in the development of Eucalyptus grandis, Pinus elliottii and Peltophorum dubium seedlings. The survey of the soil microorganism population was carried out in a greenhouse during 60 days and the treatments consisted of applications of copper sulphate (0.7; 0.708; 0.716; 0.724 mg Kg-1 to the soil and to eucalyptus and pinus seedlings. Eucalyptus and Peltophorum dubium seedlings inoculated and not inoculated with Pisolithus microcarpus (Cooke and Massee Cunn (UFSC Pt 116 received copper levels of 0, 100, 200 and 300 mg kg-1. The height, stem diameter, shoot and root fresh biomass, shoot and root dry biomass and ectomycorrhizal colonization were evaluated at 110 days. Soil bacteria and fungus population were altered by the presence of copper and the eucalyptus and pinus seedlings were not affected by copper addition. The inoculation of the eucalyptus and canafístula seedlings with isolate UFSC Pt 116 favored the height of the plants and the development of shoot and root fresh biomass. According to the results, canafístula was able to form an ectomycorrhizal association with the isolate tested. The eucalyptus and canafístula seedling development was inhibited by copper following inoculation with the UFSC Pt 116 isolate.

  8. 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.

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. IDENTIFICATION AND QUANTIFICATION OF DIFFERENTIALLY EXPRESSED GENES ASSOCIATED WITH CITRUS BLIGHT (Citrus spp.

    Directory of Open Access Journals (Sweden)

    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.

  15. Prey preference and host suitability of the predatory and parasitoid carabid beetle, Lebia grandis, for several species of Leptinotarsa beetles.

    Science.gov (United States)

    Weber, Donald C; Rowley, Daniel L; Greenstone, Matthew H; Athanas, Michael M

    2006-01-01

    Lebia grandis (Coleoptera: Carabidae), recorded as a parasitoid only on Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae), is capable of parasitizing the false potato beetle, L. juncta, and also L. haldemani. Historical records show that L. decemlineata, while the only recorded host, was not present in much of the original range of L. grandis, and may not have been its host prior to its expansion into eastern North America, where L. juncta is endemic. Our laboratory comparisons suggest that L. juncta, the presumptive original host, best supports the development of the parasitoid larval L. grandis, based on 43.6% successful emergence of the adult carabid parasitoid, compared to 11.5% from the two other Leptinotarsa species. L. grandis adults accept eggs and larvae of all 3 Leptinotarsa species as adult food. Naive, newly-emerged adults show no preference when presented the 3 species of third-instar larvae, which they consume at a mean rate of 3.3 per day, a rate which does not differ significantly by sex, larval host, or weight at emergence. When presented with equal amounts by weight of the 3 species of Leptinotarsa eggs, such adults consume the equivalent of 23.0 L. decemlineata eggs per day, with consumption of L. juncta eggs 67% higher by weight than L. decemlineata consumption. Insight into the biotic and abiotic limitations on L. grandis should aid in determining its potential for suppression of Colorado potato beetle by biological control in diverse agroecosystems.

  16. Impacts of grazing and mowing on reproductive behaviors of Stipa grandis and Stipa krylovii in a semi-arid area

    Institute of Scientific and Technical Information of China (English)

    Hui GAO; YuBao GAO; XingDong HE

    2014-01-01

    Disturbance can affect biomass allocation of plants, but can it influence plant reproductive behavior? To address this issue, we performed field plant community investigations and explored the reproductive behaviors of Stipa grandis and Stipa krylovii in response to grazing and mowing treatments at Maodeng pasture of Xilinguole League of Inner Mongolia, China during 2007-2009. The results showed that, with a similar niche width for the two plant species under mowing and grazing treatments, mowing significantly increased the ratio of ramet to genet number of S. krylovii and the carbon to nitrogen ratio of S. grandis, and grazing significantly decreased the ratio of vegetative to reproductive tiller biomass of S. grandis and increased the ratio of vegetative to reproductive tiller number of S. krylovii. Regression analysis showed that the significantly positive effect of root to shoot biomass ratio was stronger on the ratio of vegetative to reproductive tiller number of S. grandis than on that of S. krylovii. These results indicated that grazing and mowing influenced the reproductive manner and the process of sexual reproduc-tion of S. grandis and S. krylovii.

  17. MODIFICACIÓN AL PROCESO DE PRODUCCIÓN MASIVA DE LOS PARASITOIDES Catolaccus grandis Y Catolaccus hunteri

    Directory of Open Access Journals (Sweden)

    Marco Antonio Reyes-Rosas

    2010-01-01

    Full Text Available El presente estudio se realizó con el objetivo de modificar la tecnología de producción masiva de Catolaccus grandis y Catolaccus hunteri, himenópteros parasitoides de Anthonomus grandis el picudo del algodonero en Tamaulipas, México en el 2002. Se determinó la eficiencia del papel toalla para el secado de manos, en el sellamiento de cápsulas moldeadas en cera de hidrocarburos y poliolefina (LCHP, donde se confina al huésped, y evaluar la efectividad del gorgojo del garbanzo Callosobruchus maculatus como hospedante facticio para la cría de ambos parasitoides. Hubo producción masiva de C. grandis y C. hunteri utilizando C. maculatus como huésped y el papel toalla fue efectivo para sellar los orificios de las cápsulas moldeadas en LCHP. La producción masiva de C. grandis y C. hunteri mediante C. maculatus, contribuyó a incrementar la seguridad y facilidad del proceso, además de una significativa reducción de costos. El papel toalla en el sellado de los orificios de las cápsulas moldeadas en LCHP, redujo en un 50% por m2 los costos del proceso, sin afectar la eficiencia del parasitismo y emergencia de C. grandis.

  18. Genome-wide identification and functional analysis of S-RNase involved in the self-incompatibility of citrus.

    Science.gov (United States)

    Liang, Mei; Yang, Wei; Su, Shiying; Fu, Lili; Yi, Hualin; Chen, Chuanwu; Deng, Xiuxin; Chai, Lijun

    2017-04-01

    S-RNase-based self-incompatibility is found in Solanaceae, Rosaceae, and Scrophulariaceae, and is the most widespread mechanism that prevents self-fertilization in plants. Although 'Shatian' pummelo (Citrus grandis), a traditional cultivated variety, possesses the self-incompatible trait, the role of S-RNases in the self-incompatibility of 'Shatian' pummelo is poorly understood. To identify genes associated with self-incompatibility in citrus, we identified 16 genes encoding homologs of ribonucleases in the genomes of sweet orange (Citrus sinensis) and clementine mandarin (Citrus clementine). We preliminarily distinguished S-RNases from S-like RNases with a phylogenetic analysis that classified these homologs into three groups, which is consistent with the previous reports. Expression analysis provided evidence that CsRNS1 and CsRNS6 are S-like RNase genes. The expression level of CsRNS1 was increased during fruit development. The expression of CsRNS6 was increased during the formation of embryogenic callus. In contrast, we found that CsRNS3 possessed several common characteristics of the pistil determinant of self-incompatibility: it has an alkaline isoelectric point (pI), harbors only one intron, and is specifically expressed in style. We obtained a cDNA encoding CgRNS3 from 'Shatian' pummelo and found that it is homolog to CsRNS3 and that CgRNS3 exhibited the same expression pattern as CsRNS3. In an in vitro culture system, the CgRNS3 protein significantly inhibited the growth of self-pollen tubes from 'Shatian' pummelo, but after a heat treatment, this protein did not significantly inhibit the elongation of self- or non-self-pollen tubes. In conclusion, an S-RNase gene, CgRNS3, was obtained by searching the genomes of sweet orange and clementine for genes exhibiting sequence similarity to ribonucleases followed by expression analyses. Using this approach, we identified a protein that significantly inhibited the growth of self-pollen tubes, which is the defining

  19. Using morphometrics, in situ observations and genetic characters to distinguish among commercially valuable Hawaiian black coral species; a redescription of Antipathes grandis Verrill, 1928 (Antipatharia : Antipathidae)

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Daniel [University of Hawaii, Manoa, Honolulu; Toonen, Robert J. [Hawaii Institute of Marine Biology, Kaneohe, HI; Brugler, Mercer R. [University of Louisiana, Lafayette; France, Scott C. [University of Louisiana, Lafayette; Opresko, Dennis M [ORNL; Montgomery, Anthony D. [Honolulu State Department Land and Natural Resources, HI

    2010-01-01

    The commercially valuable Hawaiian black coral Antipathes grandis Verrill, 1928 is redescribed based on reexamination of the holotype from the Bernice P. Bishop Museum and field collections of 34 specimens from depths of 27-127 m. The first scanning electron micrographs of A. grandis skeletal spines are provided, along with a series of in situ color photographs and morphometric measurements of spines and polyps. Three color morphotypes were collected in the field (red, pale red, and white), none of which could be differentiated based on morphological or genetic characters (two mitochondrial and two nuclear markers). In situ observations are used in conjunction with morphological and genetic characters to distinguish among the commercially valuable Hawaiian black coral species A. grandis and A. griggi Opresko, 2009. A. grandis is differentiated from A. griggi by its finer and more irregular branching, smaller and more closely-spaced polyps, and conical spines that are smaller and not characterized by bifurcations towards their apex. Morphologically, the species most closely resembling A. grandis is A. caribbeana Opresko, 1996 from the Caribbean. Among analyzed congenerics, DNA sequences of A. grandis were likewise most similar to those of A. caribbeana for three of the four molecular markers used in this study. A combination of low genetic variability, incomplete taxonomic sampling, and unexpected similarity between A. caribbeana and the unbranched whip coral Stichopathes cf. occidentalis (Gray, 1860), hindered our ability to determine the sister relationship of A. grandis. However, in no phylogenetic reconstruction did A. grandis group sister to its sympatric congener A. griggi.

  20. Flooding impairs Fe uptake and distribution in Citrus due to the strong down-regulation of genes involved in Strategy I responses to Fe deficiency in roots.

    Directory of Open Access Journals (Sweden)

    Mary-Rus Martínez-Cuenca

    Full Text Available This work determines the ffects of long-term anoxia conditions--21 days--on Strategy I responses to iron (Fe deficiency in Citrus and its impact on Fe uptake and distribution. The study was carried out in Citrus aurantium L. seedlings grown under flooding conditions (S and in both the presence (+Fe and absence of Fe (-Fe in nutritive solution. The results revealed a strong down-regulation (more than 65% of genes HA1 and FRO2 coding for enzymes proton-ATPase and Ferric-Chelate Reductase (FC-R, respectively, in -FeS plants when compared with -Fe ones. H+-extrusion and FC-R activity analyses confirmed the genetic results, indicating that flooding stress markedly repressed acidification and reduction responses to Fe deficiency (3.1- and 2.0-fold, respectively. Waterlogging reduced by half Fe concentration in +FeS roots, which led to 30% up-regulation of Fe transporter IRT1, although this effect was unable to improve Fe absorption. Consequently, flooding inhibited 57Fe uptake in +Fe and -Fe seedlings (29.8 and 66.2%, respectively and 57Fe distribution to aerial part (30.6 and 72.3%, respectively. This evidences that the synergistic action of both enzymes H+-ATPase and FC-R is the preferential regulator of the Fe acquisition system under flooding conditions and, hence, their inactivation implies a limiting factor of citrus in their Fe-deficiency tolerance in waterlogged soils.

  1. Shoot-tip Grafting of Late-ripening Tangan(Citrus tankan Tanaka) and Identification of Virus Diseases%迟熟蕉柑茎尖嫁接及其病毒鉴定

    Institute of Scientific and Technical Information of China (English)

    王明召; 区善汉; 娄兵海; 刘升球; 梅正敏; 陈贵峰; 麦适秋; 陈宜超; 莫健生

    2009-01-01

    采用田间结果树上的芽作为接穗进行茎尖嫁接,最终获得7株茎尖嫁接苗.对所获得的茎尖嫁接苗,应用指示植物腊斯克枳橙、墨西哥来檬和伊特洛格香橼亚利桑那861-S-1分别鉴定柑橘碎叶病、衰退病和裂皮病,用PCR检测技术鉴定柑桔黄龙病.结果表明:1、3、4、5、6号迟熟蕉柑单株不带碎叶病、衰退病、裂皮病和黄龙病,可用作繁殖无病毒苗木的备选材料.%Buds from grown trees in field were used as cions of shoot-tip grafting.,and 7 seedlings were obtained by the shoot-tip grafting technique. Rusk citrange, Mexican lime and Citron 861-S-1 were used as indicator plants to identify Citrus Tatter Leaf Virus (CTLV), Citrus Tristeza Virus (CTV) and Citrus Exocortis Viroid (CEVd), respectively, and PCR technique was used to detecting Citrus Huanglongbing (HLB) on the 7 seedlings. The results were following: no pathogen of CTLV, CTV, CEVd and HLB could be fund from number 1, 3, 4, 5, 6 seedlings of Late-ripening Jiaogan , and can be used for virus-free seedling propagation .

  2. Solarization of nursery soil induces production of fruit bodies of mushrooms and enhances growth of tropi-cal forest tree seedlings

    Directory of Open Access Journals (Sweden)

    R.K. Verma

    2013-12-01

    Full Text Available The aim of this work was to find out the effect of soil solarization on microbial population and its effect on growth of two species of tropical forest trees. For this purpose, solar heating of nursery seedbeds (1 x 5m was done during April- May 2009 for one month, by application of a thin clear sheet of polyethylene. The top soil (5 inches consists of a mix of loam soil, sand and farm yard manure in 2:1:0.5 ratios (v/v. Temperature variations were recorded daily for a period of one month, at 2 depths, (5 cm and 10 cm. Maximum differences in temperature between solar treatment and control was recorded as high as 12.1° C at 5 cm and 9.1° C at 10 cm depth. After one month, population of Aspergillus, Fusarium, Penicillium, Rhizopus and nematodes were completely eliminated from upper 5 cm depth, although population of AM fungi, bacteria and Trichoderma were reduced, but not completely eliminated. Seedlings of Gmelina arborea Roxb. and Tectona grandis Linn.f. were raised through seeds on treated and control beds. After three months, the production of fruit bodies of mushrooms, namely Amanita populiphila Tullos & E. Moses, Lepiota longicauda Henn. and Scleroderma sp. were observed. It was noticed that these mushrooms only appeared on treated soil with white mycelial growth in rhizosphere under fruit bodies. Lepiota longicauda produced the maximum number of fruit bodies on teak seedbeds followed by Scleroderma sp. on G. arborea seedbeds. Due to solar heating there was 23.9% increase in plant height and 22.1% increase in collar diameter of G. arborea seedlings, where as 17.4% increase in plant height and 9.8% increase in collar diameter in case of T. grandis, as compared to control seedlings.

  3. Efecto de hongos micorrizogenos en dos patrones de cítricos limón rugoso, Citrus jambhiri, y mandarina cleopatra, Citrus reshni

    Directory of Open Access Journals (Sweden)

    Torres Héctor R.

    1989-12-01

    Full Text Available En un suelo ácido, a 1.100 msnm, se sembraron semillas de dos patrones de cítricos Citrus reshni y C. jambhiri conservadas en dos temperaturas 8 .10 0C y ambiente, almacenadas por diferentes tiempos. Plántulas de estos patrones se inocularon, al momento del trasplante a bolsas, con cepas micorrizógenas en suelo natural y suelo desinfestado. Se estableció una relación entre área foliar y el producto largo máximo por ancho máximo de las hojas. Con 30 días de almacenamiento se obtuvo el mayor porcentaje de emergencia, en temperaturas de 8-10° C se conservó más la semilla. En C. reshni las especies Acaulospora longulata + Entrophospora colombiana superaron a Glomus manihotis y al testigo en los dos tipos de suelo; en C. jambhiri en suelo natural la inoculación fue efectiva. Se encontraron coeficientes de determinación R2 mayores de 99% para ecuaciones de regresión lineal entre área foliar y largo x ancho de las hojas, y con muestras pequeñas se pudo estimar con exactitud el área foliar de patrones de cítricos en estado de vivero.Seeds of two citrus partners, Citrus reshni and C. jambhiri, preserved under two different temperatures-environmental temperature and temperature from 80 to 10 C were planted in an acid soil at 1.100 meters above sea level. In transplanting to bags, seedlings of these partners were inoculated with micorrhizal strains in a natural soil and in non-infected soil. A relationship among foliar area and the maximen length product by the maximum width in the leaves was established. The greatest emergency percentage was obtained during thirty days of storage; at temperatures from 8° to 10°C, the seed was better preserved. In C. reshni species Acaulospora longulata +Entrophospora colombiana exceeded Glomus manihotis and the control in both types of soil, in C. jambhiri in natural soil inoculation was effective. R2 over 99 % were found for linear regression among the foliar area and the length and width of the

  4. Tolerance of Anadenanthera peregrina to Eucalyptus camaldulensis and Eucalyptus grandis essential oil as condition for mixed plantation

    Directory of Open Access Journals (Sweden)

    Neimar de Freitas Duarte

    2012-06-01

    Full Text Available With the purpose of selecting the species of woody Caatinga for mixed plantations with Eucalyptus spp., the allelophatic effects of E. camaldulensis and E. grandis essential oil were studied on the growth activities of Anadenanthera peregrina. The plants were closed in glass chambers in the presence of volatile oil of E. camaldulensis or E. grandis at the concentration of 13 nl.cm-3. The number of leaves, height and diameter at soil lever were compared before, immediately after and after 30 days. Chlorophyll a and b, carotenoids and dry mass were evaluated after the treatment application. There was no inhibitory effect of E. camaldulensis and E. grandis oils on A. peregrina. E. camaldulensis, which was more adapted to semi-arid conditions, was planted in mixture stands with two native legume species, inoculated with Rhizobium and arbuscular mycorrhizal fungi. E. camaldulensis did not inhibit native species growth after two years of cultivation.

  5. 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.

  6. 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.

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

    Science.gov (United States)

    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.

  8. Efficacy of Chaetomium Species as Biological Control Agents against Phytophthora nicotianae Root Rot in Citrus.

    Science.gov (United States)

    Hung, Phung Manh; Wattanachai, Pongnak; Kasem, Soytong; Poeaim, Supattra

    2015-09-01

    Thailand is one of the largest citrus producers in Southeast Asia. Pathogenic infection by Phytophthora, however, has become one of major impediments to production. This study identified a pathogenic oomycete isolated from rotted roots of pomelo (Citrus maxima) in Thailand as Phytophthora nicotianae by the internal transcribed spacer ribosomal DNA sequence analysis. Then, we examined the in vitro and in vivo effects of Chaetomium globosum, Chaetomium lucknowense, Chaetomium cupreum and their crude extracts as biological control agents in controlling this P. nicotianae strain. Represent as antagonists in biculture test, the tested Chaetomium species inhibited mycelial growth by 50~56% and parasitized the hyphae, resulting in degradation of P. nicotianae mycelia after 30 days. The crude extracts of these Chaetomium species exhibited antifungal activities against mycelial growth of P. nicotianae, with effective doses of 2.6~101.4 µg/mL. Under greenhouse conditions, application of spores and methanol extracts of these Chaetomium species to pomelo seedlings inoculated with P. nicotianae reduced root rot by 66~71% and increased plant weight by 72~85% compared to that in the control. The method of application of antagonistic spores to control the disease was simple and economical, and it may thus be applicable for large-scale, highly effective biological control of this pathogen.

  9. Toxicity to cotton boll weevil Anthonomus grandis of a trypsin inhibitor from chickpea seeds.

    Science.gov (United States)

    de P G Gomes, Angélica; Dias, Simoni C; Bloch, Carlos; Melo, Francislete R; Furtado, José R; Monnerat, Rose G; Grossi-de-Sá, Maria F; Franco, Octávio L

    2005-02-01

    Cotton (Gossypium hirsutum L.) is an important agricultural commodity, which is attacked by several pests such as the cotton boll weevil Anthonomus grandis. Adult A. grandis feed on fruits and leaf petioles, reducing drastically the crop production. The predominance of boll weevil digestive serine proteinases has motivated inhibitor screenings in order to discover new ones with the capability to reduce the digestion process. The present study describes a novel proteinase inhibitor from chickpea seeds (Cicer arietinum L.) and its effects against A. grandis. This inhibitor, named CaTI, was purified by using affinity Red-Sepharose Cl-6B chromatography, followed by reversed-phase HPLC (Vydac C18-TP). SDS-PAGE and MALDI-TOF analyses, showed a unique monomeric protein with a mass of 12,877 Da. Purified CaTI showed significant inhibitory activity against larval cotton boll weevil serine proteinases (78%) and against bovine pancreatic trypsin (73%), when analyzed by fluorimetric assays. Although the molecular mass of CaTI corresponded to alpha-amylase/trypsin bifunctional inhibitors masses, no inhibitory activity against insect and mammalian alpha-amylases was observed. In order to observe CaTI in vivo effects, an inhibitor rich fraction was added to an artificial diet at different concentrations. At 1.5% (w/w), CaTI caused severe development delay, several deformities and a mortality rate of approximately 45%. These results suggested that CaTI could be useful in the production of transgenic cotton plants with enhanced resistance toward cotton boll weevil.

  10. Localization and transcriptional responses of Chrysoporthe austroafricana in Eucalyptus grandis identify putative pathogenicity factors

    Directory of Open Access Journals (Sweden)

    Ronishree Mangwanda

    2016-12-01

    Full Text Available Chrysoporthe austroafricana is a fungal pathogen that causes the development of stem cankers on susceptible Eucalyptus grandis trees. Clones of E. grandis that are partially resistant and highly susceptible have been identified based on the extent of lesion formation on the stem upon inoculation with C. austroafricana. These interactions have been used as a model pathosystem to enhance our understanding of interactions between pathogenic fungi and woody hosts, which may be different to herbaceous hosts. In previous research, transcriptomics of host responses in these two clones to C. austroafricana suggested roles for salicylic acid and gibberellic acid phytohormone signalling in defense. However, it is unclear how the pathogen infiltrates host tissue and which pathogenicity factors facilitate its spread in the two host genotypes. The aim of this study was to investigate these two aspects of the E. grandis-C. austroafricana interaction and to test the hypothesis that the pathogen possesses mechanisms to modulate the tree phytohormone-mediated defenses. Light microscopy showed that the pathogen occurred in most cell types and structures within infected E. grandis stem tissue. Notably, the fungus appeared to spread through the stem by penetrating cell wall pits. In order to understand the molecular interaction between these organisms and predict putative pathogenicity mechanisms of C. austroafricana, fungal gene expression was studied in vitro and in planta. Fungal genes associated with cell wall degradation, carbohydrate metabolism and phytohormone manipulation were expressed in planta by C. austroafricana. These genes could be involved in fungal spread by facilitating cell wall pit degradation and manipulating phytohormone mediated defense in each host environment, respectively. Specifically, the in planta expression of an ent-kaurene oxidase and salicylate hydroxylase in C. austroafricana suggests putative mechanisms by which the pathogen can

  11. Genetic resources of teak (Tectona grandis Linn. f.)—strong genetic structure among natural populations

    DEFF Research Database (Denmark)

    Hansen, Ole Kim; Changtragoon, Suchitra; Ponoy, Bundit;

    2015-01-01

    Twenty-nine provenances of teak (Tectona grandis Linn. f.) representing the full natural distribution range of the species were genotyped with microsatellite DNA markers to analyse genetic diversity and population genetic structure. Provenances originating from the semi-moist east coast of India...... had the highest genetic diversity while provenances from Laos showed the lowest. In the eastern part of the natural distribution area, comprising Myanmar, Thailand and Laos, there was a strong clinal decrease in genetic diversity the further east the provenance was located. Overall, the pattern...... of the findings for conservation and use of genetic resources of the species are discussed....

  12. Influence of Planting Spacing on Mechanical Properties of Eucalyptus grandis × E. urophylla Planted in China

    Institute of Scientific and Technical Information of China (English)

    HENSON; Michael

    2008-01-01

    The objective of this study was to understand influence of planting spacing on mechanical properties of Eucalyptus grandis × E. urophylla planted as a potential species for solid wood products in China. Four trees at age of 13 were selected from each of 6 groups of planting spacing and a total of 24 sampling trees were selected from the Dongmen Forestry Center of Guangxi Province in China. Furthermore, a one-meter-long log from each tree was cut into small blocks for wood properties testing. MOE, MOR and co...

  13. 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.

  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. 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.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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.

  1. 江华县柑橘黄龙病发生特点及防控对策%Occurrence Characteristics and Control Measures of Citrus Huanglongbing in Jianghua County

    Institute of Scientific and Technical Information of China (English)

    蒋章富; 莫昌乐

    2016-01-01

    2008年以来,江华瑶族自治县大力发展柑橘产业,现已形成3334 hm2的规模,但柑橘黄龙病却成为柑橘进一步发展的制约因素。对近年来江华瑶族自治县柑橘黄龙病发生情况、症状特点及其发生的影响因素进行了认真分析,并提出了详细的防控对策,即加强检疫,培育无病苗木,挖除病树,减少病菌来源,防治柑橘木虱,消灭传播媒介,加强果园管理,培育健壮树势。%Since 2008, citrus industry developed speedily in Jiang Hua Yao Autonomous County. While citrus planting area extended to 3 334 hm2, citrus Huanglongbing became a constraint to further development. By analyzing the occurrence condition, symptoms of citrus Huanglongbing and its inlfuencing factors, some control measures were proposed, including imposing strict quarantine, cultivating disease-free seedling, controlling citrus psyllid timely, strengthening the management of orchard, and cultivateing strong tree.

  2. 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

  3. Antraquinonas e naftoquinonas do caule de um espécime de reflorestamento de Tectona grandi (Verbenaceae Anthraquinones and naphtoquinones from the bark of Tectona grandis (Verbenaceae reforestation specimen

    Directory of Open Access Journals (Sweden)

    Rafael Y.O. Moreira

    2006-09-01

    Full Text Available O fracionamento do extrato hexânico do caule de um espécime de reflorestamento de Tectona grandis (Verbenaceae, através de procedimentos fitoquímicos clássicos, levou ao isolamento das naftoquinonas lapachol e desidro-a-lapachona e das antraquinonas tectoquinona e obtusifolina. As estruturas das substâncias foram caracterizadas através da análise de métodos espectrométricos de RMN. Este é o primeiro estudo fitoquímico de um espécime de reflorestamento de Tectona grandis, no Brasil, sendo o objetivo principal deste trabalho a comprovação da presença de tectoquinona em espécimes cultivados.The hexane extract of the bark of Tectona grandis (Verbenaceae afforded two anthraquinones and two naphtoquinones. Their caracterizations were obtained through NMR spectroscopic techniques. This is the first phytochemical study of the bark of Tectona grandis reforestation specimen in Brazil. The main interest in this work is proving the presence of tectoquinone in reforestation specimen.

  4. 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.

  5. Effects of Exogenous Putrescine on Mycorrhiza, Root System Architecture, and Physiological Traits of Glomus mosseae-Colonized Trifoliate Orange Seedlings

    Directory of Open Access Journals (Sweden)

    Qiang-Sheng WU

    2012-11-01

    Full Text Available Putresince (Put as one of the important polyamines (PAs has been identified to regulate mycorrhizal development of citrus plants. The present study was to screen an efficient concentration of Put application at the range of 0.05-1 mM on the trifoliate orange (Poncirus trifoliata seedlings colonized by Glomus mosseae, in terms of growth, root system architecture, and chlorophyll and carbohydrate contents. Compared to the non-Put treatment, all the Put treatments, especially 0.05 mM Put, significantly increased mycorrhizal colonization of tap root in addition to first, second, and third order lateral roots. The mycorrhizal seedlings treated by 0.05, 0.1, and 1 mM Put showed greater growth (stem diameter, height, leaf number, and fresh mass and root morphological properties ( tap root length, projected and surface areas, and volume and higher numbers of first, second, and third order lateral roots. Bio-molecules like chlorophyll a, total chlorophyll, and carotenoid contents of the seedlings were significantly increased by the Put treatments at 0.05-1 mM. All exogenous Put application at the range of 0.05-1 mM significantly decreased sucrose contents but increased glucose contents of leaves and roots. This study suggests that exogenous Put can significantly improve growth performance and root system architecture, besides changes in physiological traits of AMF seedlings. The 0.05 mM concentration of Put showed the best effects.

  6. Effects of potassium and sodium supply on drought-adaptive mechanisms in Eucalyptus grandis plantations.

    Science.gov (United States)

    Battie-Laclau, Patricia; Laclau, Jean-Paul; Domec, Jean-Christophe; Christina, Mathias; Bouillet, Jean-Pierre; de Cassia Piccolo, Marisa; de Moraes Gonçalves, José Leonardo; e Moreira, Rildo Moreira; Krusche, Alex Vladimir; Bouvet, Jean-Marc; Nouvellon, Yann

    2014-07-01

    A basic understanding of nutrition effects on the mechanisms involved in tree response to drought is essential under a future drier climate. A large-scale throughfall exclusion experiment was set up in Brazil to gain an insight into the effects of potassium (K) and sodium (Na) nutrition on tree structural and physiological adjustments to water deficit. Regardless of the water supply, K and Na supply greatly increased growth and leaf area index (LAI) of Eucalyptus grandis trees over the first 3 yr after planting. Excluding 37% of throughfall reduced above-ground biomass accumulation in the third year after planting for K- supplied trees only. E. grandis trees were scarcely sensitive to drought as a result of the utilization of water stored in deep soil layers after clear-cutting the previous plantation. Trees coped with water restriction through stomatal closure (isohydrodynamic behavior), osmotic adjustment and decrease in LAI. Additionally, droughted trees showed higher phloem sap sugar concentrations. K and Na supply increased maximum stomatal conductance, and the high water requirements of fertilized trees increased water stress during dry periods. Fertilization regimes should be revisited in a future drier climate in order to find the right balance between improving tree growth and limiting water shortage.

  7. Genetic effects of rainforest fragmentation in an early successional tree (Elaeocarpus grandis).

    Science.gov (United States)

    Rossetto, M; Jones, R; Hunter, J

    2004-12-01

    Rainforests in Australia and around the world have been extensively cleared and degraded. It is essential to recognize the changes in population diversity and dynamics that follow habitat fragmentation if better conservation and management strategies are to be developed. This study is an investigation of the medium term (over 100 years) effects of rainforest fragmentation on a long-lived, early successional tree species within a habitat matrix that includes various types of fragmented and undisturbed sites. Five microsatellite loci were used to assess the level and distribution of genetic variation across the southern range of Elaeocarpus grandis (Elaeocarpaceae). In all, 21 sites were sampled to provide a direct comparison between fragmented and undisturbed populations. Overall levels of diversity (A=3.4, He=0.568, f=0.094) were higher than those of closely related endemic species, but lower than those recorded across other rainforest trees. No significant genetic structure was detected across this species, suggesting the existence of efficient dispersal and colonization mechanisms responsible for the maintenance of gene flow. Rainforest fragments, and in particular those within the extensively cleared Big Scrub, show a trend for increased inbreeding levels caused by a loss of heterozygosity within juvenile cohorts. However, the overall rate of genetic decline within fragmented rainforests appears to be more subtle in E. grandis than across other species. A combination of ecological attributes and evolutionary history is likely to have contributed to this outcome and need to be considered in future rainforest restoration projects.

  8. Mast Cell Stabilizing,Antianaphylactic and Antihistaminic Activity of Coccinia grandis Fruits in Asthma

    Institute of Scientific and Technical Information of China (English)

    Dnyaneshwar J Taur; Ravindra Y Patil

    2011-01-01

    Coccinia grandis Linn(Curcubitaceae)is a climber herb cultivated throughout India.In traditional medicine fruits have been used to treat leprosy,fever,asthma,bronchitis and jaundice.In present study,ethanol extract of C.grandis fruit(ECGF)at 100,125 and 150 mg·kg-1,i.p.,was evaluated for mast cell stabilizing,antianaphylactic and antihistaminic activity using egg albumin induced mast cell degranulation in mice;passive cutaneous anaphylaxis in rats and clonidine induced catalepsy in mice respectively.ECGF at(100-150 mg·kg-1,i.p.)significantly protected egg albumin induced degranulations of mast cells and caused reduction of blue dye leakage in passive cutaneous anaphylaxis in dose dependently.The treatment ECGF also inhibited clonidine induced catalepsy in dose dependent manner.Phytochemical studies observed presence of saponin,steroids,alkaloids,flavonoids and glycosides.In conclusion ECGF possesses mast cell stabilizing;anti anaphylactic and antihistaminic potential which might be used in treatment of asthma.

  9. Use of glass transition temperature for stabilization of board's cracks of Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Fred W. Calonego

    2010-09-01

    Full Text Available The Eucalyptus grandis logs temperatures were determined and correlated with the board's cracks during steaming. Thermocouples were inserted in the logs center, registering their temperatures during steaming at 90"C. The logs were sawed and the board's cracks measured. It was concluded that: (1 the logistic S-shaped curve explains the logs temperature variation; (2 the logs with diameter of 20 to As temperaturas em toras de Eucalyptus grandis, durante a vaporização, foram determinadas e correlacionadas com as rachaduras das tábuas. Nos centros das toras foram inseridos termopares e registradas suas temperaturas durante a vaporização à 90"C. As toras foram desdobradas e as rachaduras das tábuas mensuradas. Concluiu-se que: (1 o modelo estatístico sigmoidal logístico explica a variação da temperatura nas toras; (2 as toras com 20 a <25, 25 a <30 e 30 a <35 cm de diâmetro apresentaram, respectivamente, 84,2"C, 73,1"C e 45,8"C ao final da vaporização; e (3 as rachaduras foramsignificativamente menores nas toras que atingiram a temperatura de transição vítrea.

  10. Characterization and rheological study of the galactomannan extracted from seeds of Cassia grandis.

    Science.gov (United States)

    Albuquerque, Priscilla B S; Barros, Wilson; Santos, Gustavo R C; Correia, Maria T S; Mourão, Paulo A S; Teixeira, José A; Carneiro-da-Cunha, Maria G

    2014-04-15

    Galactomannan extracted from seeds of Cassia grandis with 0.1M NaCl, followed by ethanol precipitation, presented a yield of 36 ± 8%. The polysaccharide has a constant mannose/galactose ratio (2.44:1). Methylation analysis, one and two dimensional NMR spectroscopy confirmed that the polysaccharide has a central core composed of 4-linked β-mannose units, with branches of galactose, linked to the carbohydrate core through α(1-6) linkage. The amorphous nature of the galactomannan was confirmed by X-ray diffraction. Rheological characterization exhibited Newtonian plateaus followed by shear-thinning zones characteristic of polymer solutions up to 1.5% (w/v) and above this value the system exhibited yield stress associated with a weak gel. Adjusting stress-strain curves confirmed a 1.6% (w/v) as the galactomannan concentration value for the sol-gel transition. These results indicate that the galactomannan extracted from C. grandis seeds presents rheological characteristics suitable for applications in pharmaceutical, biomedical, cosmetic and food industries.

  11. Physical characterization of particleboard panels made from Eucalyptus grandis with addition of industrial wood residues

    Directory of Open Access Journals (Sweden)

    Fernanda Cristina Pierre

    2014-06-01

    Full Text Available In Brazil, the wood from planted forests constitutes the main material source for the production of particleboards. The utilization of forest residues for production of these panels was not implemented in industrial level yet. This work had the objective of evaluating the physical properties of three layers particleboard, industrially manufactured, using wood of Eucalyptus grandis from plantation and industrial wood residues in different ratios (adittion from 10% to 35% in volume. The material (Eucalyptus grandis wood and industrial residues - recycled pallets and sawdust was supplied by Eucatex S. A. Ind. e Com. located in Botucatu - Sao Paulo State, Brazil, where the panels had been manufactured in Eucatex plant. Physical tests were carried out at the Process Laboratories of Eucatex and in the Materials Testing Laboratory, Rural Engineering Department of the College of Agronomic Sciences - Sao Paulo State University - UNESP. Results revealed that panels had very good physical performance, attending, in general, to all the technical specifications established by the product standards, even in the treatments with higher addition of residues. The final moisture content of the panel presented effect in the properties studied with general trend of reduction in water absorption and swelling in thickness when the moisture content increased from 9% for 12,5%.

  12. Estimate of the density of Eucalyptus grandis W. Hill ex Maiden using near infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Silviana Rosso

    2013-12-01

    Full Text Available This study aimed to analyze use of near infrared spectroscopy (NIRS to estimate wood density of Eucalyptus grandis. For that, 66 27-year-old trees were logged and central planks were removed from each log. Test pieces 2.5 x 2.5 x 5.0 cm in size were removed from the base of each plank, in the pith-bark direction, and subjected to determination of bulk and basic density at 12% moisture (dry basis, followed by spectral readings in the radial, tangential and transverse directions using a Bruker Tensor 37 infrared spectrophotometer. The calibration to estimate wood density was developed based on the matrix of spectra obtained from the radial face, containing 216 samples. The partial least squares regression to estimate bulk wood density of Eucalyptus grandis provided a coefficient of determination of validation of 0.74 and a ratio performance deviation of 2.29. Statistics relating to the predictive models had adequate magnitudes for estimating wood density from unknown samples, indicating that the above technique has potential for use in replacement of conventional testing.

  13. Quality of wood and pulp from a clone of Eucalyptus grandis planted at three locations

    Directory of Open Access Journals (Sweden)

    Cláudio Angeli Sansígolo

    Full Text Available Eucalyptus grandis is one of the most popular species to use as raw material for pulp production in Brazil, as it provides excellent pulping, bleaching and papermaking results. The main objective of this study is to examine the quality of wood and pulp from a clone of Eucalyptus grandis, at age 4 years approximately, planted in three different soils, two of which being low fertility and one being a superior fertility soil, and their reflections on wood quality and pulping results. Chemical analyses of the soils followed guidelines developed by Raij et al. (2001, while physical and chemical properties of the wood followed ABTCP, TAPPI and ABNT standards. Chemical analyses of the soils pointed to lower fertility in Fazenda Limeira and Fazenda Tapera Queimada as opposed to higher fertility in Fazenda Mendes União. Results revealed stronger tendencies for the stand grown in the less fertile soils (Fazenda Limeira and Fazenda Tapera Queimada in comparison to the stand grown in more fertile soil (Fazenda Mendes União as to: higher wood and bark basic density, lower height and dry matter content, higher bark content, lower extractives content and higher holocellulose content, higher total and screened yields from pulping, lower specific wood consumption/t of pulp, and higher tear and tensile indices at low refining levels.

  14. Genetic resources of teak (Tectona grandis Linn. f.)—strong genetic structure among natural populations

    DEFF Research Database (Denmark)

    Hansen, Ole Kim; Changtragoon, Suchitra; Ponoy, Bundit

    2015-01-01

    Twenty-nine provenances of teak (Tectona grandis Linn. f.) representing the full natural distribution range of the species were genotyped with microsatellite DNA markers to analyse genetic diversity and population genetic structure. Provenances originating from the semi-moist east coast of India ...

  15. Mycorrhizal symbionts of Pisonia grandis and P. sechellarum in Seychelles: identification of mycorrhizal fungi and description of new Tomentella species.

    Science.gov (United States)

    Suvi, Triin; Tedersoo, Leho; Abarenkov, Kessy; Beaver, Katy; Gerlach, Justin; Kõljalg, Urmas

    2010-01-01

    Nyctaginaceae includes species that are predominantly non-mycorrhizal or form arbuscular or ectomycorrhiza. Root-associated fungi were studied from P. grandis and P. sechellarum roots collected respectively on the islands of Cousin and Silhouette in Seychelles. In addition fungal sporocarps were collected from the sampling area. Fungal symbionts were identified from the roots by anatomotyping and rDNA sequencing; sporocarps collected were examined microscopically and sequenced. Three distantly related ectomycorrhizal fungal species belonging to Thelephoraceae were identified from the roots of P. grandis. Sporocarps also were found for two symbionts and described as new Tomentella species. In addition Tomentella species collected from other Seychelles islands were studied and described as new species if there was no close resemblance to previously established species. P. sechellarum was determined to be an arbuscular mycorrhizal plant; three arbuscular mycorrhizal fungal species were detected from the roots. P. grandis is probably associated only with species of Thelephoraceae throughout its area. Only five Tomentella species are known to form ectomycorrhiza with P. grandis and they never have been found to be associated with another host, suggesting adaptation of these fungi to extreme environmental conditions in host's habitat.

  16. Evaluating variations of physiology-based hyperspectral features along a soil water gradient in a Eucalyptus grandis plantation

    NARCIS (Netherlands)

    Cho, M.A.; Aardt, van J.; Main, R.; Majeke, B.

    2010-01-01

    Remote sensing is viewed as a cost-effective alternative to intensive field surveys in assessing site factors that affect growth of Eucalyptus grandis over broad areas. The objective of this study was to assess the utility of hyperspectral remote sensing to discriminate between site qualities in E.

  17. Interspecific hybridization and inbreeding effect in seed from a Eucalyptus grandis x E. urophylla clonal orchard in Brazil

    Directory of Open Access Journals (Sweden)

    Campinhos Eduardo N.

    1998-01-01

    Full Text Available We used allozyme markers to estimate the amount of natural hybridization between Eucalyptus grandis and E. urophylla in a 7.4-hectare commercial hybrid-seed orchard planted in Espírito Santo, Brazil. This orchard was planted in 1982 using a honeycomb design, with each hexagonal plot containing one E. grandis tree surrounded by six E. urophylla trees. There were 267 replicated hexagonal plots in the orchard. Seeds were harvested from the E. grandis clone only. The multilocus outcrossing rate estimated for the E. grandis clone averaged 70.2%, ranging from 33.0 to 99.0% among individual trees. Contaminant pollination, inferred from progeny genotypes containing alleles not present in the seven parental clones, accounted for 14.4% of the hybrid seed. Contaminant pollen was attributed to neighboring eucalyptus stands isolated from the orchard by a 400-m wide belt of native forest. Inbred and hybrid progenies were identified by their allozyme genotypes and transplanted to the field. Field growth of inbred progeny was 30% lower than that of hybrid plants at two and three years of age.

  18. HPTLC METHOD OF QUANTITATION OF BIOACTIVE MARKER CONSTITUENT PINITOL IN EXTRACTS OF PISONIA GRANDIS (R.BR

    Directory of Open Access Journals (Sweden)

    G. Poongothai

    2012-09-01

    Full Text Available Pisonia grandis R.Br. is an evergreen medicinal plant in the four O'clock family of Nyctaginaceae. Leaves, stems and root of this plant are extensively used by tribals in India to prepare several folk medicines to treat rheumatism, arthritis and diabetes. Recently pinitol has been reported from the leaves of Pisonia grandis and thus the present study was designed to quantify this antidiabetic molecule in the various extracts of leaves of Pisonia grandis by high performance thin layer chromatography (HPTLC. The calibration curve of a stabilized HPTLC method was linear in the range of 1.5 to 7.0µg per spot and the correlation coefficient was found to be 0.9718, thus exhibiting good linearity between concentration and area. The limit of quantification (LOQ and limit of detection (LOD was found to be 1.5 and 1.2 µg respectively. The present study also revealed that among all the extracts, PGSX3 and PGSX4 contain more than 8 µg of pinitol per milligram of extract and thus exhibited chloroform: methanol mixture (9:1 and 100 % ethanol are found to be effective solvents to extract pinitol from Pisonia grandis. This is the first report on quantitation of pinitol by HPTLC.

  19. In vitro xanthine oxidase inhibitory activity of leaves, fruits and peel extracts of Citrus aurantium, Citrus limetta and Citrus limon

    Directory of Open Access Journals (Sweden)

    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.

  20. 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...

  1. 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...

  2. Observações citológicas em citrus: lll. megasporogênese, fertilização e poliembrionia

    Directory of Open Access Journals (Sweden)

    Osvaldo Bacchi

    1944-01-01

    Full Text Available É apresentada uma revisão geral da megasporogênese, fertilização, formação do endosperma e poliembrionia em Citrus, tendo sido confirmada, pelas observações nas espécies C. paradisi Macf. e C. aurantium L., a maioria das conclusões feitas por Strassburger (10 e Osawa (6. É descrita uma nova forma de poliembrionia causada pela existência, em alguns casos, de dois gametófitos num mesmo óvulo; explica-se, dêste modo, a origem de dois híbridos não idênticos em uma mesma semente. Três formas de poliembrionia são, portanto, conhecidas em Citrus : a a poliembrionia nucelar, dando origem a um número variável de "seedlings" "maternais" idênticos e derivados do nucelo; 2 a poliembrionia por clivagem (4, 5, originada pela suposta bipartição do embrião sexual; e 3 a poliembrionia causada pela ocorrência de mais de um gametófito normal no mesmo óvulo. O endosperma em Citrus pertence ao tipo nuclear.1. A general review is presented of megasporogenesis, fertilization, endosperm formation and polyembryony in Citrus, most of the findings of Strassburger (10 and Osawa (6 having been confirmed through investigation of C. parodisi Macf. and C. aurantium L. 2. A new form of polyembryony is presented, caused by the existence in some instances of two gametophytes in the same ovule. The origin of two non-identical hybrids from the same seed is thus explained. 3. Three forms of polyembryony are therefore known in Citrus, (a nucellar embryony, giving rise to a variable number of identical, "maternal" seedlings derived from the nucellus ; (b cleavage polyembryony (4, 5 originating through fission of the generative embryo; and (c polyembryony caused by the occurrence of more than one normal gametophyte in the same ovule. The endosperm in Citrus is free.

  3. Brotación in vitro de yemas de teca (Tectona grandis L. f. Sprouting buds in vitro teak (Tectona grandis L. f.

    Directory of Open Access Journals (Sweden)

    Fabiana Rojas Parajeles

    2012-11-01

    Full Text Available La teca (Tectona grandis L.f. es una especie maderable exótica introducida a Costa Rica para la siembra de plantaciones comercial por la alta demanda de su madera, su rápido crecimiento y su alta calidad. Inicialmente se utilizó la semilla como único material de siembra y la pobre calidad de muchas de las plantaciones impulsó el inicio de programas de mejora genética. La propagación clonal tomó mucha importancia en estos programas y el cultivo in vitro se convirtió en una herramienta valiosa para la propagación masiva de los árboles élites. Por lo anterior, este trabajo se enfocó en evaluar el efecto de varias concentraciones de dos reguladores de crecimiento, bencilaminopurina (BA y ácido indolacético (AIB, solos y en combinación, en la brotación de yemas dormantes y formación de callos de teca. Tanto el análisis estadístico como la observación visual mostraron que el tratamiento que consistió de 0,005 mg/l de AIA fue el mejor para incrementar la brotación de las yemas y para disminuir la formación de callo.Teak (Tectona grandis L. f. is an exotic timber species introduced to Costa Rica for commercial plantations due to the high demand for its wood, rapid growth and high-quality. Initially the seed was use as the only planting material, but the poor quality of many of the plantations resulted in the initiation of genetic improvement programs. The introduction of clonal propagation in these programs and the establishment of in vitro culture techniques became import tools for mass propagation of the selected elite trees. On the foregoing, this work focused on assessing the effect of several concentrations of two growth regulators, benzylaminopurine (BA and indole acetic acid (AIB, alone and in combination, in the budding of dormantes buds and callus formation of teak. Both the statistical analysis and the visual observation showed that the treatment consisted of 0.005 mg/l of IAA was the best to increase the budding of the

  4. Organogênese de explante foliar de clones de Eucalyptus grandis x E. urophylla Organogenesis of the leaf explant of Eucalyptus grandis x E. urophylla clones

    Directory of Open Access Journals (Sweden)

    Elisa Cristina Soares de Carvalho Alves

    2004-05-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos dos reguladores de crescimento TDZ [1-fenil-3-(1,2,3-tia-diazol-5-iluréia], BAP (6-benzilaminopurina e ANA (ácido naftalenoacético no desempenho da propagação in vitro por organogênese de explante foliar de três clones híbridos de Eucalyptus grandis x Eucalyptus urophylla. Houve resposta diferenciada dos clones quanto a intensidade, textura e coloração dos calos, em razão dos tratamentos com os reguladores de crescimento. Os melhores resultados de calejamento dos três genótipos foram observados nos tratamentos com a combinação dos reguladores de crescimento TDZ (0,5 mg L-1 e ANA (0,1 mg L-1, obtendo-se 100% de calejamento no explante foliar. Os piores resultados de calejamento foram observados nos tratamentos com a combinação dos reguladores de crescimento BAP (0,1 mg L-1 e ANA (0,1 mg L-1. Em relação à regeneração, a melhor resposta foi obtida com 1,0 mg L-1 BAP em que 8% dos calos formados a partir de explantes foliares regeneraram gemas, com número médio destas formadas por calo igual a 4,2.The aim of this work was to evaluate the effects of growth regulators TDZ [1-phenil-3-(1,2,3-thiadiazol-5-yl urea], BAP (6-benzilaminopurine e NAA (Naphthalene acetic acid on the in vitro propagation by organogenesis from foliar explants of Eucalyptus grandis x E. urophylla. Depending on the clone used, there were singular responses to growth regulators treatment regarding callusing intensity, texture and color. The best results of the three genotypes used were observed with the TDZ (0.5 mg L-1 and NAA (0.1 mg L-1 treatment, where 100% of the foliar explants presented callus. The worst results were observed with the BAP (0.1 mg L-1 and NAA (0.1 mg L-1 treatment. Subsequently, considering the regeneration process, the best response was achieved with 1.0 mg L-1 BAP, in which 8% of the calli regenerated buds, with an average of 4.2 buds per explant.

  5. Revisión taxonómica de Alytes grandis Brunner (Amphibia, Anura

    Directory of Open Access Journals (Sweden)

    Sanchiz, B.

    1986-12-01

    Full Text Available The holotype and only existing remain referred to Alytes grandis Brunner, 1957, presumably a discoglossid frog from the German Pleistocene, is examined and compared with other living and fossil Palaearctic anurans. The analysis rejects its validity as an independent extinct species, as The material is clearly within the known variability of living Rana temporaria Linnaeus, 1758, of which it should be considered merely a sinonym.

    Se examina el holotipo y único resto atribuido de Alytes grandis Brunner, 1957, un supuesto discoglósido del Pleistoceno alemán, comparándose con otros anuros actuales y fósiles del Paleártico. El análisis permite desechar su pertenencia a una especie extinta independiente, siendo en cambio atribuible con toda claridad a la viviente Rana temporaria Linnaeus, 1758, de la que debe considerarse sinónimo.
    Zum systematischen Status von Alytes grandis Brunner, 1957 (Amphibia, Anura. Der bislang einzig bekannte und von Brunner (1957 beschriebene Rest zu Alytes grandis aus pleistozänen Ablagerungen der Breitenberghöhle bei Gössweinstein (Fränk, Alb wird beschrieben und aufgrund ausführlicher Vergleichsuntersuchungen der rezenten Art Rana temporaria Linnaeus, 1758, zugeordnet, Alytes grandis Brunner, 1957, ist somit als synonyrn zu Rana temporaria zu betrachten.

  6. Aboveground nutrient components of Eucalyptus camaldulensis and E. grandis in semiarid Brazil under the nature and the mycorrhizal inoculation conditions

    Institute of Scientific and Technical Information of China (English)

    Marcela C. Pagano; Antonio F. Bellote; Maria R. Scotti

    2009-01-01

    A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grandis plantations in the semiarid region (15° 09' S 43° 49' W) in the north of the State of Minas Gerais in Brazil. Results show that the total above-ground biomass (dry matter) was 33.6 Mg·ha-1 for E. camaldulensis and 53.1 Mg·ha-1 for E. grandis. The biomass of the stem wood, leaves, branches, and stem bark for E. camaldulensis accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively (Table 2); meanwhile a similar partition of the total above-ground biomass was also found for E. grandis. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%, 0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk (bark and wood), nutrient accumulation in general was lower. Nutrient content of E. grandis presented little variation compared with that of E. camaldulensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of nutrients, especially in E. grandis. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this semi-arid region. The two species showed mycotrophy.

  7. Characterization of the low affinity transport system for NO(3)(-) uptake by Citrus roots.

    Science.gov (United States)

    Cerezo, M; Flors, V; Legaz, F; García-Agustín, P

    2000-12-07

    Three-month old citrange Troyer (hybrid of Citrus sinensis x Poncirus trifoliata) seedlings were grown hydroponically and, after a period of NO(3)(-) starvation, plants were transferred to solutions enriched with K(15)NO(3) (96% atoms 15N excess) to measure 15NO(3)(-) uptake rates as a function of external 15NO(3)(-) concentrations. Two different NO(3)(-) uptake systems were found. Between 1 and 50 mM 15NO(3)(-) in the uptake solution medium, the uptake rate increased linearly due to the low affinity transport system (LATS). Nitrate reductase activity showed the same response to external [NO(3)(-)], and also appears to be regulated by the rate of nitrate uptake. Nitrate pre-treatments had a represive effect on NO(3)(-) uptake rate measured at 5 or 30 mM external [15NO(3)(-)]. The extent of the inhibition depended on the [NO(3)(-)] during the pre-treatment and in the uptake solution. These results suggest that the LATS of Citrus seedlings is under feedback control by the N status of the plant. Accordingly, addition of amino acids (Glu, Asp, Asn, Gln) to the uptake solution resulted in a decrease in 15NO(3)(-) uptake rate. However, the inactivation of nitrate reductase activity after treatment of the seedlings with either 100 or 500 µM WO(4)(2-) did not affect the activity of the LATS. Metabolic uncouplers, 2,4-DNP and KCN, reduced the uptake rate by 43.3% and 41.4% respectively at 5mM external [15NO(3)(-)]. However, these compounds had little effect when 15NO(3)(-) uptake was assayed at 30 mM external concentration. The ATPase inhibitors DCCD and DES reduced 15NO(3)(-) uptake by 68.8%-35.6%, at both external [15NO(3)(-)]. Nitrate uptake by the LATS declined with the increase of the solution pH beyond pH 4. The data presented are discussed in the context of the kinetics, energy dependence and regulation of NO(3)(-) uptake.

  8. 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.

  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. Environ: E00194 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00194 Citrus peel (non-JP) Kippi Crude drug Essential oil Citrus tachibana [TAX:200544], Citrus... leiocarpa [TAX:237569], Cirus grandis [TAX:37334], Citrus unshiu [TAX:55188], Citrus reticulat...a [TAX:85571] Same as: D06897 Rutaceae (rue family) Citrus tachibana, Citrus leiocarpa, Cirus grandis fruit peel, or Citrus... unshiu, Citrus reticulata fruit peel; Standards for non-pharmacopoeial crude drugs ...

  11. 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.

  12. Desiccation sensitivity and cryopreservation of excised embryonic axes of Citrus suhuiensis cv. limau madu, Citrumelo [Citrus paradisi macf. × Poncirus trifoliata (l.) raf.] and Fortunella polyandra.

    Science.gov (United States)

    Al Zoubi, O M; Normah, M N

    2012-01-01

    Excised embryonic axes from seeds of three taxa, namely, Citrus suhuiensis cv. limau madu, Citrumelo (Citrus paradisi x Poncirus trifoliate) and Fortunella polyandra, were desiccated in a laminar airflow, over silica gel, and ultra-rapidly. Desiccation sensitivity (WC50) was estimated for each taxon using the quantal response model. High desiccation tolerance (WC50 = 0.11 g water per g dry mass. g/gdw) was observed for limau madu embryonic axes desiccated in a laminar airflow and ultra-rapidly (WC50 =0.10 g/gdw). Desiccation tolerance was substantially lower (WC50 = 0.19 g/gdw) for silica gel dehydration. Similarly, high desiccation tolerance (WC50 = 0.15 g/gdw) was associated with F. polyandra embryonic axes when desiccated in a laminar airflow, while a lower desiccation tolerance (WC50 = 0.17 g/gdw) was observed with silica gel dehydration. Ultra-rapid desiccation led to the highest desiccation tolerance (WC50 = 0.14 g/gdw). The dehydration rate, however, had no influence on desiccation tolerance (WC50 ~ 0.14 g/gdw) for Citrumelo embryonic axes. After each desiccation period, embryonic axes were directly immersed in liquid nitrogen (LN) followed by rapid rewarming. Normal seedling recovery of 80 to 83% for excised embryonic axes of limau madu was observed for laminar airflow and ultra-rapid dehydration, but for silica gel dehydration, 57% recovery was obtained. Similarly, for Citrumelo, high recoveries of 100% and 97% were obtained from axes desiccated in a laminar airflow and using ultra-rapid dehydration, respectively, whereas a lower value was associated with silica gel dehydration (80%). For F. polyandra, 50% recovery was obtained both for laminar airflow and ultra-rapid dehydration, while much lower recovery (43%) was associated with silica gel dehydration. Regardless of the drying method employed, axis survival percentages following exposure to LN were commensurate with the desiccation sensitivity pattern.

  13. PRODUÇÃO DE MUDAS DE Eucalyptus grandis EM SUBSTRATOS ORGÂNICOS ALTERNATIVOS

    Directory of Open Access Journals (Sweden)

    Rodrigo Ferreira da Silva

    2014-09-01

    Full Text Available http://dx.doi.org/10.5902/1980509815745Estudos referentes ao descarte de resíduos orgânicos urbanos e agroindustriais tornaram-se imprescindíveis pela possibilidade de seu uso na produção de mudas florestais e pelo impacto ambiental que seria provocado pelo descarte inadequado. O objetivo do trabalho foi avaliar o crescimento de mudas de Eucalyptus grandis submetidas a diferentes tipos e combinações de substratos orgânicos urbano e agroindustriais. O experimento foi desenvolvido em casa de vegetação sob delineamento experimental inteiramente casualizado, com 10 tratamentos constituídos por diferentes substratos e proporções de combinação dos mesmos (100% Composto Orgânico de Lixo Urbano (COLU; 100% Composto Orgânico de Resíduo Agroindustrial (CORA; 100% Substrato Comercial; 25% COLU + 75% Comercial; 25% CORA + 75% Comercial; 25% COLU + 75% Solo; 50% COLU + 50% Comercial; 50% CORA + 50% Comercial; 50% Comercial + 50% Solo e 100% Solo e 12 repetições. Avaliaram-se altura da planta, diâmetro do colo, número de folhas, comprimento entre nós, massa fresca da parte aérea e do sistema radicular, massa seca da parte aérea e do sistema radicular, massa seca total, comprimento da raiz principal, comprimento do sistema radicular, volume do sistema radicular, raio médio das raízes, área superficial específica do sistema radicular e estabilidade de torrão. Os substratos contendo composto orgânico de lixo urbano apresentam grande potencialidade de uso como substratos alternativos na produção de mudas de Eucalyptus grandis. A mistura de substrato comercial ao composto orgânico de lixo urbano possibilita crescimento do sistema radicular e parte aérea das mudas de Eucalyptus grandis. A mistura de 50% de substrato comercial e 50% composto orgânico de resíduo agroindustrial proporciona maior crescimento de diâmetro de caule em relação aos tratamentos contendo solo ou em relação ao composto orgânico de res

  14. Cold Resistance Nutrient Characters with Ten Kinds of Fungus in Eucalyptus urophylla × E.grandis%桉树内生菌对尾巨桉幼苗抗寒生理指标的影响

    Institute of Scientific and Technical Information of China (English)

    谢安强; 洪伟; 吴承祯

    2012-01-01

    E. urophylla X E. grandis seedlings were inoculated with 10 strains of eucalyptus endophytic fungi by irrigating the fungus suspension, and then subjected to low temperature stress 30 days later. The results showed that compared with the control the soluble sugar (SS) content increased by 41.11%, 11. 11% , 32.78% , 38. 89% and 6.67% in treatment 1,8,5,7,10, respectively. The soluble protein (SP) content was 14.90%, 0.72%, 10.94%, 3.37% , 24.40% and 0.36% higher in treatment 1,2,5,6,7,10 than that in the control. The proline content was 28.77% ,22. 11% ,20. 16% ,11.25% ,5.48% and 1.57% higher in treatment 5,7,1,2,4,9 than that in the control. The chlorophyll content was 9. 52% ,7. 48% ,7. 48% ,6. 80% ,5. 44% ,3. 40% ,3. 40% ,2. 72% ,2. 04% and 2. 04% higher in treatment 6,8,10,1,9,5,7,4,2,3 than that in the control. After being inoculated with strain 1 of the fungus, the cold-resistant capability of eucalyptus was much improved in terms of nutrition characteristics. However, the more physiological characteristics may be needed to determine whether the fungus can be applied in production.

  15. 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 ...

  16. 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

  17. Modification of the original color of the Eucalyptus grandis wood by heat treatments

    Directory of Open Access Journals (Sweden)

    Rosilei Aparecida Garcia

    2014-09-01

    Full Text Available The objective of this study was to determine the modification of original color of Eucalyptus grandis Hill ex. Maiden wood after heat-treatment. Wood samples were heat-treated under different temperatures (180, 200, 215 and 230ºC and time conditions (15 minutes, 2 and 4 hours. Color analysis were performed on the CIE L*a*b* system by using a Color Eye XTH-X-Rite 200d spectrophotometer. All heat treatments promoted an alteration of the original color of wood. Heat-treated woods presented lower L* (lightness values than untreated wood (control, characterizing the wood darkness, mainly for more severe conditions of temperature and time. Chromatic coordinates (a* and b* showed different behaviors depending on the temperature-time combination. The modification of the original color of the wood allowed the creation of new color patterns, which can add greater value to the studied wood.

  18. Chemical Composition of Essential Oil from the Peel of Chinese Torreya grandis Fort

    Directory of Open Access Journals (Sweden)

    Tao Feng

    2011-01-01

    Full Text Available The composition of the peel essential oil of Torreya grandis fort obtained by cold pressing and steam distillation was determined by GC and GC/MS. 62 constituents accounting for 99.6% of the total pressed oil were identified while 59 compounds accounting for 99.4% of the steam distilled oil were identified. Limonene (35.6–37.1%, α-pinene (20.1–24.1%, and δ-carene (3.3–3.9 were the major constituents. Others include γ-carene (3.8-3.9%, germacrene D (2.5–2.9%, and β-farnesene (2.7-2.8%.

  19. Development Potential, in a Greenhouse, of Cuttings of the Hybrid Eucalyptus grandis x Eucalyptus camaldulensis

    Directory of Open Access Journals (Sweden)

    M. N. Garcia

    2013-03-01

    Full Text Available Abstract: This study evaluated the potential for development in the greenhouse, cuttings of the hybrid of Eucalyptus grandis x Eucalyptus camaldulensis in Sinop - Mato Grosso and generated equations to estimate the percentage of rooting parameters. Were measured: the percentage of cuttings with some degree of modification, the percentage of cuttings in the percentage of cuttings with roots larger than 10 cm in length. Also measured was the neck diameter, height and leaf area index. The heights and leaf area showed lower development within the greenhouse. The rooting potential is based on curve speed of rooting and was found 12 days after staking. The identification of the optimal point of withdrawal of the shoots of the greenhouse through the intercept curves daily current increase curve (DCI e daily average increase (DAI, being 19 days after staking. The company derives the stakes with 24 days underdoing the potential of the species and structures used.Keywords: Eucalyptus, greenhouse management and rooting

  20. Quantification by allometric equations of carbon sequestered by Tec-tona grandis in different agroforestry systems

    Institute of Scientific and Technical Information of China (English)

    Avinash Jain; S. A. Ansari

    2013-01-01

    Non destructive methods for quantification of carbon seques-tration in tropical trees are inadequately developed. We described a stan-dardized method for estimating carbon stock in teak (Tectona grandis Linn. F.). We developed linear allometric equations using girth at breast height (GBH), height and age to quantify above ground biomass (AGB). We used AGB to estimate carbon stock for teak trees of different age groups (1.5, 3.5, 7.5, 13.5, 18.5 and 23.5 years). The regression equation with GBH, y=3.174x-21.27, r2=0.898 (p teak-wheat (56.92%)>teak-wild oat (54.94%)>teak-gram (37.15%)>teak-ashwagandha (11.86%). The results from GBH-based regression equations provided satisfactory estimates of carbon stock in tropical trees.

  1. Wood properties of Eucalyptus grandis and Pinus caribaea estimated by colorimetry

    Directory of Open Access Journals (Sweden)

    Patrícia Gomes Ribeiro Amorim

    2013-09-01

    Full Text Available The use of non-destructive technologies has been very effective in characterization and evaluation of wood quality. This study aimed to characterize the technologically wood of Pinus caribaea and Eucalyptus grandis by Colorimetry. The study was conducted at the University of Brasilia (UNB in Physics and Engineering Laboratory the Laboratory of Forest Products/LPF - Brazilian Forest Service (SFB. Species were subjected to standard tests of basic density, shrinkage and bending. For the colorimetric determination of the parameters it was used a spectrophotometer according to the methodology adopted by Camargos (1999. The radial surface of the wood is most suitable for the collecting of the colorimetric parameters and prediction of properties. Property best estimated by this technique was the density, followed by modulus of elasticity (MOE and modulus of rupture (MOR.

  2. EFFECT OF THE STEAMING ON THE DRYING OF Eucalyptus grandis BOARDS

    Directory of Open Access Journals (Sweden)

    Raphael Nogueira Rezende

    2015-03-01

    Full Text Available The objective of this work was to evaluate the effect of the steaming on the drying rate and drying quality of Eucalyptus grandis boards. For this purpose, wood from an experimental plantation of the Federal University of Lavras, Minas Gerais State, Brazil, with 24 years of age was used. Trees were felled and sectioned in logs and the logs were sawn by a tangential system. Half of the boards volume were steamed during 3 hours at 90ºC of temperature and 100% of relative humidity after the heating of the drying process. The other half was not steamed (control. The boards were dried in the dry-kiln and the resulting defects from the drying process and drying rate were determined. The results indicated that the steaming was effective in increase of the drying rate in 15% and decrease of the drying defects of 20 to 52%.

  3. Diversity of seedling responses to drought

    NARCIS (Netherlands)

    Slot, M.; Poorter, L.

    2007-01-01

    Drought is an important seedling mortality agent in dry and moist tropical forests, and more severe and frequent droughts are predicted in the future. The effect of drought on leaf gas exchange and seedling survival was tested in a dry-down experiment with four tree species from dry and moist forest

  4. Effect of the fractions of Coccinia grandis on Ethanol-Induced cerebral oxidative stress in rats

    Directory of Open Access Journals (Sweden)

    M Umamaheswari

    2009-01-01

    Full Text Available The present study was aimed at investigating the effect of the various fractions of hydromethanol extract of the leaves of Coccinia grandis (Cucurbitaceae against ethanol-induced cerebral oxidative stress in rats. The leaves of this species is used in traditional medicine for treating jaundice, bronchitis, skin eruptions, burns, rheumatism, syphilis, gonorrhoea, etc. Cerebral oxidative stress was induced in rats by the administration of 20% ethanol (5 ml/100 g b.w. for 28 days. The pet-ether (PEF, chloroform (CF, ethylacetate (EAF and residual (RF fractions at a dose of 200 mg/kg b.w. were simultaneously administered with ethanol orally for 28 days. Vitamin E at a dose of 100 mg/kg orally was used as the standard. Administration of ethanol resulted in a significant increase in the activities of serum transaminases, alkaline phosphatase, uric acid and lipid levels. In addition, there was a significant elevation in the levels of malondialdehyde and lipid hydroperoxides and a reduction in the activities of enzymatic and non-enzymatic antioxidants in the brain. Simultaneous administration of the fractions prevented the enzymatic leakage and the rise in uric acid and lipid levels. All the fractions (except the residual fraction prevented the peroxidative damage caused by ethanol, which is evidenced from the improved antioxidant potential. Further, histopathological examination of the brain tissue revealed that the fractions offered significant protection against ethanol toxicity. Among the fractions tested, the chloroform fraction exhibited appreciable antioxidant property, which was almost comparable with the standard Vitamin E. These results suggest that the leaves of Coccinia grandis exhibit significant antioxidant activity in ethanol-treated rats.

  5. 沙田柚多倍体基因组AFLP分析%Genome Analysis of Nature and Artificial Polyploids by AFLP in Citrus grandis.cv.Shatianyou

    Institute of Scientific and Technical Information of China (English)

    何波; 汪卫星; 向素琼; 刘秀芳; 李晓林; 郭启高; 梁国鲁

    2009-01-01

    沙田柚性状优良却多核,通过多倍体选育获得无核或少核品种具有很高的价值.本研究运用AFLP技术分析沙田柚多倍体基因组的变化,以期为多倍化选育优良品种提供一定的理论依据.结果表明,多倍体沙田柚基因组存在大量片段的丢失,也有许多新的酶切位点出现,变异率在21 %~29 %之间.其中多个位点同时发生了相同变异,暗示着多倍体基因组的进化并不是一个随机事件,而这些变异与哪些表观遗传变异直接相关,还有待深入研究.

  6. 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...

  7. Behavioral assay on Asian citrus psyllid attraction to orange jasmine

    Science.gov (United States)

    The Asian citrus psyllid (ACP) is an important pest because it transmits a bacterium putatively responsible for huanglongbing, a devastating citrus disease. Research on ACP chemical ecology is of interest with respect to identifying attractants and repellents for managing the psyllid. We report on a...

  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. Water and nitrogen use efficiencies in citrus production

    NARCIS (Netherlands)

    Qin, Wei; Assinck, F.B.T.; Heinen, Marius; Oenema, Oene

    2016-01-01

    Water and nitrogen (N) are two key limiting factors for citrus production. Reported effects of water and N inputs on citrus yield, water use efficiency (WUE) and N use efficiency (NUE) vary greatly, mainly due to differences in cultivars, tree age, climate, soil types, and water and N input level

  10. Changes in anthocyanin production during domestication of citrus

    Science.gov (United States)

    Mandarin (C. reticulata), citron (C. medica) and pummelo (C. maxima) are imortant fruit species of the genus Citrus and parents of the interspecific hybrids that constitute the most familiar commercial varities of citrus: sweet orange, sour orange, clementine, lemon lme and grapefruit. Citron and it...

  11. 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...

  12. 21 CFR 74.302 - Citrus Red No. 2.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Citrus Red No. 2. 74.302 Section 74.302 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES SUBJECT TO CERTIFICATION Foods § 74.302 Citrus Red No. 2. (a) Identity. (1) The color...

  13. Identification and expression analysis of early cold-induced genes from cold-hardy Citrus relative Poncirus trifoliata (L.) Raf.

    Science.gov (United States)

    Sahin-Çevik, Mehtap

    2013-01-10

    Citrus is one of the most economically important fruit crops growing in subtropical and tropical regions. Most commercially important Citrus varieties are susceptible to cold; therefore, low and freezing temperatures are the main limiting factors for citrus production in subtropical areas. Since Poncirus trifoliata (L.) Raf. is a cold-hardy, interfertile Citrus relative, it serves as a genetic resource for improving cold tolerance in cold sensitive commercial Citrus species. While gene induced in response to long-term cold acclimation was previously identified in Poncirus, early response of Poncirus to cold has not been explored in detail. To identify early cold-responsive genes, a subtractive cDNA library was constructed using 4-h cold-treated and untreated control Poncirus seedlings in this study. A total of 210 randomly picked clones from the subtracted library with cold-induced genes were sequenced. The sequences obtained from the majority of these clones shared homology with previously identified cold-induced and/or environmental stress-regulated genes in other plants. Reverse northern blot analysis of the expression of these cDNAs with cold-treated and untreated control probes revealed that expression of 64 cDNAs was increased two to 11 fold in response to 4-h cold treatment. While the majority of these genes were related with cell rescue, defense, cell death and aging, transcription, metabolism, protein fate, energy, cellular communication and signal transduction, transport facilitation and development, some of them did not show homology with genes with known functions. Individual expression analysis of nine selected genes by semi-quantitative RT-PCR using mRNA from cold-treated and untreated control plants confirmed that the expression of selected cDNAs was all induced in response to cold. The results demonstrated that although a few genes were commonly induced in response to both short and long-term cold acclimation in Poncirus, majority of early cold

  14. 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.

  15. Somatic Embryogenesis: Still a Relevant Technique in Citrus Improvement.

    Science.gov (United States)

    Omar, Ahmad A; Dutt, Manjul; Gmitter, Frederick G; Grosser, Jude W

    2016-01-01

    The genus Citrus contains numerous fresh and processed fruit cultivars that are economically important worldwide. New cultivars are needed to battle industry threatening diseases and to create new marketing opportunities. Citrus improvement by conventional methods alone has many limitations that can be overcome by applications of emerging biotechnologies, generally requiring cell to plant regeneration. Many citrus genotypes are amenable to somatic embryogenesis, which became a key regeneration pathway in many experimental approaches to cultivar improvement. This chapter provides a brief history of plant somatic embryogenesis with focus on citrus, followed by a discussion of proven applications in biotechnology-facilitated citrus improvement techniques, such as somatic hybridization, somatic cybridization, genetic transformation, and the exploitation of somaclonal variation. Finally, two important new protocols that feature plant regeneration via somatic embryogenesis are provided: protoplast transformation and Agrobacterium-mediated transformation of embryogenic cell suspension cultures.

  16. Dissipation and residue of forchlorfenuron in citrus fruits.

    Science.gov (United States)

    Chen, Weijun; Jiao, Bining; Su, Xuesu; Zhao, Qiyang; Qin, Dongmei; Wang, Chengqiu

    2013-06-01

    Field trials were carried out in three provinces of China to study the dissipation and residue of forchlorfenuron in citrus fruits. The results had shown that the degradation rate of forchlorfenuron in citrus fruits followed the first-order kinetics equation C = A∙eBt. The half-lives of forchlorfenuron were 15.8-23.0 days, the final residues of forchlorfenuron in pulp were all ≤0.002 mg/kg, and most of the residues were concentrated in the peel. The risk assessment revealed that no significant potential health risk would be induced by forchlorfenuron in citrus fruits. Therefore, it could be safe to apply forchlorfenuron in citrus fruits, and the results of this study could also be regarded as a reference to the setting of maximum residue limit for forchlorfenuron in citrus fruits in China.

  17. Digestion kinetics of carbohydrate fractions of citrus by-products.

    Science.gov (United States)

    Lashkari, Saman; Taghizadeh, Akbar

    2015-01-01

    The present experiment was carried out to determine the digestion kinetics of carbohydrate fractions of citrus by-products. Grapefruit pulp (GP), lemon pulp (LE), lime pulp (LI) and orange pulp (OP) were the test feed. Digestion kinetic of whole citrus by-products and neutral detergent fiber (NDF) fraction and acid detergent fiber (ADF) fractions of citrus by-products were measured using the in vitro gas production technique. Fermentation kinetics of the neutral detergent soluble carbohydrates (NDSC) fraction and hemicelluloses were calculated using a curve subtraction. The fermentation rate of whole was the highest for the LE (p fractions. There was no significant difference among potential gas production (A) volumes of whole test feeds (p fractions of citrus by-products have high potential for degradability. It could also be concluded that carbohydrate fractions of citrus by-products have remarkable difference in digestion kinetics and digestive behavior.

  18. Simulated drift effect of glyphosate in different parts of Eucalyptus grandis plantsEfeito da deriva simulada de glyphosate em diferentes partes da planta de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Maria Renata Rocha Pereira

    2012-10-01

    Full Text Available The present work aimed to evaluate the effects of simulated drift of glyphoste on Eucalyptus grandis, through the application of low doses in different parts of the plant. The experimental design was a randomized block design with five replications. The treatments were glyphosate application at 0; 30; 60; 90 e 120 g a.e. ha-1 of the commercial formulation Scout®. Three forms of application were used: applying on leaf, on stem, and on the entire plant (leaf + stem. For leaf application, stems were covered with plastic ribbons to protect them from the solution; the same was made with plants that were sprayed on stems, covering leaf with plastic bag. The application was carried out in an armed stationary spray tips XR 11002 VS, with 183 KPa pressure in volume of 200 L ha-1. The eucalyptus plants receiving applications in leaves and whole plant (leaves + stem showing effects of intoxication are more intense about the plants that received the stem applications only. However, there may be increases in height growth and total dry mass of eucalyptus plants in applications of 30 g a.e. ha-1 glyphosate.No presente trabalho objetivou-se avaliar os efeitos da deriva simulada de glyphoste em plantas de Eucalyptus grandis, por meio da aplicação de doses reduzidas em diferentes partes da planta. Utilizouse o delineamento inteiramente casualizado, com cinco repetições. Os tratamentos foram constituídos da aplicação de 0; 30; 60; 90 e 120 g e.a.ha-1 de glyphosate, da formulação comercial Scout®. A aplicação foi realizada de três formas: aplicação sobre as folhas, no caule e na planta inteira (folha + caule. Para a aplicação nas folhas o caule foi coberto com fitas plásticas para evitar que fosse atingido pela solução, e o mesmo foi feito com as plantas que receberam pulverização no caule, cobrindo as folhas com saco plástico. A aplicação foi realizada em um pulverizador estacionário, munido de pontas XR 11002 VS, com pressão de 183

  19. Danos visuais e anatômicos causados pelo glyphosate em folhas de Eucalyptus grandis Visible and anatomic damages caused by glyphosate in Eucalyptus grandis leaves

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2008-03-01

    Full Text Available A sintomatologia é um dos principais critérios adotados para avaliar os danos causados por fatores bióticos e abióticos em plantas. Contudo, aspectos microscópicos são necessários na compreensão dos mecanismos de intoxicação e no diagnóstico precoce da injúria. Objetivou-se no presente estudo avaliar os efeitos da deriva simulada de quatro formulações comerciais de glyphosate (Scout®, Roundup NA®, Roundup transorb® e Zapp QI® sobre a morfoanatomia foliar de seis clones de Eucalyptus grandis (UFV01, UFV02, UFV03, UFV04, UFV05 e UFV06. Após a aplicação do glyphosate na dose de 129,6 g ha-1, acompanhou-se diariamente o surgimento de sintomas, e aos 14 dias coletaram-se amostras de folhas aparentemente sadias para as análises microscópicas. Todos os clones apresentaram cloroses e necroses a partir do quarto dia de exposição, independentemente da formulação utilizada. O clone UFV04 não apresentou injúrias anatômicas. Nos demais clones, os herbicidas ocasionaram plasmólise, colapso celular, hipertrofia e formação de tecido de cicatrização, porém não foram diagnosticadas variações na espessura das folhas. Visualmente, o Roundup transorb® foi o herbicida que provocou maior intoxicação nas plantas. Anatomicamente, plantas expostas ao Roundup NA® apresentaram maior número de danos. O clone UFV06 foi o mais sensível à ação das formulações testadas, considerando-se tanto a análise visual quanto a anatômica. Os resultados confirmam o valor diagnóstico da análise visual e prognóstico da anatomia vegetal, sendo o estudo conjunto desses parâmetros fundamental para avaliar a sensibilidade entre os clones e o potencial fitotóxico de herbicidas.Symptomatology is one of the most important criteria used to determine the damages caused by biotic and abiotic factors in plants. However, microscopic aspects are needed to elucidate intoxication mechanisms and early injury diagnosis. This work aimed to evaluate the

  20. 77 FR 59709 - Citrus Greening and Asian Citrus Psyllid; Quarantine and Interstate Movement Regulations

    Science.gov (United States)

    2012-10-01

    ...: Effective October 31, 2012. FOR FURTHER INFORMATION CONTACT: Ms. Lynn Evans-Goldner, National Program... Huanglongbing disease of citrus by the international taxonomic community. We are amending the definition to... issued under Sec. 204, Title II, Public Law 106-113, 113 Stat. 1501A-293; sections 301.75-15 and...

  1. Eficiência das minicepas e microcepas na produção de propágulos de clones de Eucalyptus grandis Efficiency of ministumps and microstumps of Eucalyptus grandis clones for minicutting and microcutting production

    Directory of Open Access Journals (Sweden)

    Miranda Titon

    2003-10-01

    Full Text Available No presente estudo objetivou-se avaliar a eficiência dos jardins clonais nas técnicas de microestaquia e miniestaquia de quatro clones de Eucalyptus grandis, quanto a sobrevivência, vigor e capacidade produtiva das microcepas e minicepas em coletas sucessivas de microestacas e miniestacas. As microcepas utilizadas foram oriundas de mudas rejuvenescidas por micropropagação, mediante subcultivos in vitro, e as minicepas, de miniestacas oriundas de plantas propagadas pelo método da estaquia convencional (macroestaquia. As minicepas e as microcepas apresentaram desempenho similar, tendo sido observado, para ambas, elevada taxa de sobrevivência, vigor e capacidade produtiva de material para propagação vegetativa.The objective of this work was to evaluate the efficiency of clonal gardens in the microcutting and minicutting techniques of four Eucalyptus grandis clones regarding the survival, vigor and productive capacity of the microstumps and ministumps in successive collections of microcuttings and minicuttings. The microstumps were obtained from rejuvenated tissue explants through subculture in vitro, and the ministumps by minicuttings derived from conventional rooted cuttings. The ministumps and microstumps of E. grandis exhibited similar performance, i.e., high survival rate, vigor and productive capacity of vegetative propagation material.

  2. 76 FR 78228 - Notice of Request for Extension of Approval of an Information Collection; Citrus Greening and...

    Science.gov (United States)

    2011-12-16

    ... regulations to implement the PPA. Citrus greening, also known as Huanglongbing disease of citrus, is considered to be one of the most serious citrus diseases in the world. Citrus greening is a bacterial disease... the fruit, and can kill trees. Once infected, there is no cure for a tree with citrus greening...

  3. AVALIAÇÃO DA SUPERFÍCIE DA MADEIRA DE Eucalyptus grandis Hill ex Maiden TRATADA TERMICAMENTE

    Directory of Open Access Journals (Sweden)

    Gilmara Pires de Moura Palermo

    2015-01-01

    Full Text Available The objective of this study was to study the machined surface quality of Eucalyptus grandis wood submitted to heat treatment. The machining operations realized on the boards obtained from the processing of six trees were: planing, thicknessing, tear in horizontal drilling, drilling, drilling hinge and sanding. 208 boards of 125 x 25 x 500 mm were selected, with 104 untreated and 104 heat-treated boards at maximum temperature of 190ºC. The evaluation of the surface was performed according to ASTM D-1666/87 standard. The result showed that the Eucalyptus grandis wood presents a good behavior during the machining tests, obtaining notes 1 and 2 (excellent and good, except for drilling hinge test in the bolt hole and drilling with 12, 8, 6 mm, reaching notes between 2 and 4 (good, regular and bad. The heat treatment reduced the number of defects on the machined samples, except for torn grain in some machining operations.

  4. Agrobacterium-Mediated Transfer of Arabidopsis ICE1 Gene into Lemon (Citrus Limon (L.) Burm. F. cv. Eureka)

    Institute of Scientific and Technical Information of China (English)

    HUANG Jia-quan; SUN Zhong-hai

    2005-01-01

    The Arabidopsis ICE1 (inducer of CBF expression 1) gene was cloned through RT-PCR of Arabidopsis cDNAs and introduced into the lemon (Citrus Limon (L.) Burm. F. cv. Eureka) genome using Agrobacterium-mediated transformation method. Epicotyl segments from in vitro grown lemon seedlings were co-cultivated with A. tumefaciens strain EHA 105 carrying the binary plasmid pMVICE1, whose T-DNA region contain ICE1 gene driven by 35S CaMV promoter. Among 320 epicotyl segments inoculated, 71 explants responded and regenerated 51 elongated shoots. These shoots were subjected to an extra month of kanamycin exposure. In this way, the number of escapes reduced. Thirteen of 31 survived shoots formed roots and 7 were tested positive using PCR technique. Southern blot analyses confirmed PCR results and demonstrated that more than two copies of the ICE1 gene were integrated into the lemon genome.

  5. René Descartes, the Robots and the Soul in the debate between Tommaso Ceva and Guido Grandi

    Directory of Open Access Journals (Sweden)

    Alfredo Serrai

    2016-05-01

    Full Text Available Descartes outlined human intelligence as a divine gift, albeit in a system governed by universal laws of physics and mathematics. In the eighteenth century the camaldolite Guido Grandi and Tommaso Ceva, both mathematicians, had a dispute about the interpretation of the Cartesian model of human intelligence. This case provides an opportunity to retrace the path of a speculative techno-philosophical question concerning the human possibility to equipping robots with the ability to experience a self-consciousness.

  6. 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)

  7. Citrus tristeza virus p23: a unique protein mediating key virus-host interactions

    Directory of Open Access Journals (Sweden)

    Ricardo eFlores

    2013-05-01

    Full Text Available The large RNA genome of CTV (ca. 20 kb contains 12 open reading frames (ORFs, with the 3’-terminal one corresponding to a protein of 209 amino acids (p23 that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative Zn-finger domain and some basic motifs, is unique to CTV because no homologues have been found in other closteroviruses, including the type species of the genus Beet yellows virus (despite both viruses having many homologous genes. Consequently, p23 might have evolved for the specific interaction of CTV with its citrus hosts. From a functional perspective p23 has been involved in many roles: i regulation of the asymmetrical accumulation of CTV RNA strands, ii induction of the seedling yellows syndrome in sour orange and grapefruit, iii intracellular suppression of RNA silencing, iv elicitation of CTV-like symptoms when expressed ectopically as a transgene in several Citrus spp., and v enhancement of systemic infection (and virus accumulation in sour orange and CTV release from the phloem in p23-expressing transgenic sweet and sour orange. Moreover, transformation of Mexican lime with intron-hairpin constructs designed for the co-inactivation of p23 and the two other CTV silencing suppressors results in complete resistance against the homologous virus. From a cellular point of view, recent data indicate that p23 accumulates preferentially in the nucleolus, being the first closterovirus protein with such a subcellular localization, as well as in plasmodesmata. These major accumulation sites most likely determine some of the functional roles of p23.

  8. Investigating inhibition of microbes inducing microbiologically-influenced-corrosion by Tectona grandis based Fe-nanoparticle material

    Science.gov (United States)

    Okeniyi, Joshua Olusegun; Omotosho, Olugbenga Adeshola; Inyang, Michael Anietie; Okeniyi, Elizabeth Toyin; Nwaokorie, Ikechi Thaddeus; Adidi, Emmanuel Amanogho; Owoeye, Taiwo Felicia; Nwakudu, Kelechukwu Chinedu; Akinlabu, Deborah Kehinde; Gabriel, Olanrewaju Oyewale; Taiwo, Olugbenga Samson; Awotoye, Olufisayo Adebola

    2017-02-01

    In this paper, inhibition of microbes inducing microbiologically-influenced-corrosion (MIC) of metals by Tectona grandis based Fe (iron) Nanoparticle material was investigated. For this, extract was obtained from the leaf of Tectona grandis and this was employed as precursor for synthesizing the Fe-nanoparticle material. From this, the synthesized plant extract based nanoparticle material was characterized using scanning electron microscopy and energy dispersive spectroscopy (SEM+EDS) instrument. The developed Fe bio-nanoparticle material was then employed for sensitivity and/or resistance study application against different strains of microbes that are known to induce microbiologically-influenced-corrosion, in metallic materials, and for this, microbial growth inhibition effect was compared with that from a commercial antibiotic employed as control. Results showed that the Tectona grandis based Fe-nanoparticle exhibited good inhibition effects on the growth of many of the MIC inducing microbes investigated. Sensitivity measures of zone of inhibition against the growth of MIC inducing microbial strains either outperformed or compares well with that obtained from the commercial antibiotic control, in the study. These results indicate positive prospect on the suitability of Fe bio-nanoparticle for corrosion inhibition applications for the protection of metals against microbiological corrosion influencing environment.

  9. Evidence for salicylic acid signalling and histological changes in the defence response of Eucalyptus grandis to Chrysoporthe austroafricana

    Science.gov (United States)

    Zwart, Lizahn; Berger, Dave Kenneth; Moleleki, Lucy Novungayo; van der Merwe, Nicolaas A.; Myburg, Alexander A.; Naidoo, Sanushka

    2017-01-01

    Eucalyptus species are cultivated for forestry and are of economic importance. The fungal stem canker pathogen Chrysoporthe austroafricana causes disease of varying severity on E. grandis. The Eucalyptus grandis-Chrysoporthe austroafricana interaction has been established as a model system for studying Eucalyptus antifungal defence. Previous studies revealed that the phytohormone salicylic acid (SA) affects the levels of resistance in highly susceptible (ZG14) and moderately resistant (TAG5) clones. The aims of this study were to examine histochemical changes in response to wounding and inoculation as well as host responses at the protein level. The anatomy and histochemical changes induced by wounding and inoculation were similar between the clones, suggesting that anatomical differences do not underlie their different levels of resistance. Tyloses and gum-like substances were present after inoculation and wounding, but cell death occurred only after inoculation. Hyphae of C. austroafricana were observed inside dead and living cells, suggesting that the possibility of a hemibiotrophic interaction requires further investigation. Proteomics analysis revealed the possible involvement of proteins associated with cell death, SA signalling and systemic resistance. In combination with previous information, this study forms a basis for future functional characterisation of candidate genes involved in resistance of E. grandis to C. austroafricana. PMID:28349984

  10. Allelopathic effects of essential oil from Eucalyptus grandis × E.urophylla on pathogenic fungi and pest insects

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This study on the allelopathic effects and chemical components of the essential oil from Eucalyptus grandis × E.urophylla shows that the leaf oil emulsion of E.grandis × E.urophylla can inhibit the proliferation of pathogenic fungi Fusarium oxysporum,Pyriculerie grisea,Glorosprium musa rum and Phytophthora capsici.Pupation and feeding of the pest insects Spodopteralitura Fabricius and Helicoverpa armigera Hubner are shown to be affected with restraining effects which increase with the increasing levels of oil concentration.A GC/MS analysis of the leaf oil indicated that the main components,with a relative content of≥3%,were alloocimene (43.22%),α-pinene (13.63%),γ-terpinene (5.49%),(E)-3,7-dimethyl-2,6-octadien-1-ol (3.58%),β-fenchyl alcohol (4.58%),and 2-amino-3,5-dicyano-6-(4-methoxyphenoxy)-pyridine (3.67%).Terpenes played an important role in the inhibitory effects of E.grandis × E.urophylla essential oil on pathogenic fungi and pest insects.Poor biodiversity of eucalyptus plantations is a function of allelopathy.

  11. Seedling quality of common sage (Salvia officinalis L. as affected by seedling production methods

    Directory of Open Access Journals (Sweden)

    Ömer Çalişkan

    2006-09-01

    Full Text Available The study was conducted to determine the effects of four different seedling production methods (i.e., open seedbed, greenhouse seedbed, float system and modified float system on the seedling growth and quality of common sage. Sowing rates were 1 g per m2 in an open seedbed and a greenhouse seedbed system, whereas the sowing rate was one seed per cell in the float and modified float systems. Emergence period, seedling growth period, the fresh and dry weights of aerial parts of seedlings, the fresh and dry weights of roots, seedling height, root height and stem diameter were determined as agronomical observations and measurements. The greenhouse seedling method was found to be superior over the other methods

  12. Antibacterial activity of Citrus reticulata peel extracts.

    Science.gov (United States)

    Jayaprakasha, G K; Negi, P S; Sikder, S; Rao, L J; Sakariah, K K

    2000-01-01

    Citrus peels were successively extracted with hexane, chloroform and acetone using a soxhlet extractor. The hexane and chloroform extracts were fractionated into alcohol-soluble and alcohol-insoluble fractions. These fractions were tested against different gram positive and gram negative bacteria. The EtOH-soluble fraction was found to be most effective. Fractionation of EtOH-soluble fraction on silica gel column yielded three polymethoxylated flavones, namely desmethylnobiletin, nobiletin and tangeretin. Their structures were confirmed by UV, 1H, 13C NMR and mass spectral studies. The findings indicated a potential of these natural compounds as biopreservatives in food applications.

  13. 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

  14. Citrus huanglongbing: a newly relevant disease presents unprecedented challenges.

    Science.gov (United States)

    Wang, Nian; Trivedi, Pankaj

    2013-07-01

    Citrus huanglongbing (HLB) is one of the oldest citrus diseases and has been known for over a century. HLB is caused by 'Candidatus Liberibacter' spp. that are phloem-limited, fastidious α-proteobacteria and infect hosts in different Kingdoms (i.e., Animalia and Plantae). When compared with well-characterized, cultivatable plant-pathogenic Gram-negative bacteria, the interactions of uncultured insect-vectored plant-pathogenic bacteria, including 'Ca. Liberibacter' spp., with their hosts remain poorly understood. 'Ca. Liberibacter' spp. have been known to cause HLB, which has been rapidly spreading worldwide, resulting in dramatic economic losses. HLB presents an unprecedented challenge to citrus production. In this review, we focus on the most recent research on citrus, 'Candidatus Liberibacter asiaticus', and psyllid interactions, specifically considering the following topics: evolutionary relationships among 'Ca. Liberibacter' spp., genetic diversity, host range, genome analysis, transmission, virulence mechanisms, and the ecological importance of HLB. Currently, no efficient management strategy is available to control HLB, although some promising progress has been made. Further studies are needed to understand citrus, 'Ca. L. asiaticus', and psyllid interactions to design innovative management strategies. Although HLB has been problematic for over a century, we can only win the battle against HLB with a coordinated and deliberate effort by the citrus industry, citrus growers, researchers, legislatures, and governments.

  15. Seed Mucilage Improves Seedling Emergence of a Sand Desert Shrub

    OpenAIRE

    Xuejun Yang; Baskin, Carol C.; Baskin, Jerry M.; Guangzheng Liu; Zhenying Huang

    2012-01-01

    The success of seedling establishment of desert plants is determined by seedling emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in seedling emergence in arid sandy environments. We hypothesized that seed mucilage enhances seedling emergence in a low precipitation regime and under conditions of sand buria...

  16. Fertilização de mudas de espécies arbóreas nativas e exóticas Fertilization of native and exotic tree seedlings

    Directory of Open Access Journals (Sweden)

    Sebastião Pires de Moraes Neto

    2003-04-01

    Full Text Available Doses crescentes de fertilizante de liberação controlada (FLC foram comparadas com fertilização convencional e tratamento sem fertilização. Estes tratamentos foram testados em mudas das pioneiras Guazuma ulmifolia (mutambo, Eucalyptus grandis e Pinus caribaea var. caribaea, da secundária inicial Peltophorum dubium (canafístula e da clímax Calycophyllum spruceanum (mulateiro, as quais cresceram em casa de vegetação. As mudas foram cultivadas em tubetes de 50 cm³ de capacidade, tendo como substrato uma mistura contendo 50% de húmus de minhoca, 30% de casca de eucalipto decomposta e 20% de casca de arroz carbonizada, em base volumétrica. Aos 125 dias após a semeadura, as mudas de G. ulmifolia, E. grandis e P. dubium submetidas à fertilização convencional apresentaram maior crescimento em altura e biomassa seca da parte aérea comparados aos dos tratamentos que receberam FLC. Contudo, para estas espécies, a biomassa seca da raiz das mudas submetidas ao tratamento convencional foram semelhantes à das mudas produzidas com as duas maiores doses de FLC (4,28 e 6, 42 kg/m³ de substrato, e a razão entre raiz e parte aérea foi maior para a dose de 6,42 kg/m³ (FLC, comparada à do tratamento convencional para as duas primeiras espécies. O Calycophyllum spruceanum e o Pinus caribaea var. caribaea tiveram pequeno desenvolvimento em todos os tratamentos, aos 125 dias.Increasing doses of resin-coated controlled release fertilizers (CRF were compared with conventional fertilization and treatment without fertilizer. Five species of tree seedlings were used: the pioneers Guazuma ulmifolia (mutambo, Eucalyptus grandis and Pinus caribaea var. caribaea, the early secondary Peltophorum dubium ("canafístula" and the climax Calycophyllum spruceanum ("mulateiro", grown in greenhouse. The seedlings were tilled in plastic tubes of 50 cm³ capacity, receiving as substrate a mixture of 50% earthworm humus, 30% decomposed eucalypt bark, and 20

  17. The evolution of CMA bands in Citrus and related genera.

    Science.gov (United States)

    e Silva, Ana Emília Barros; Marques, André; dos Santos, Karla G B; Guerra, Marcelo

    2010-06-01

    Most species of Citrus and related genera display a similar karyotype with 2n = 18 and a variable number of terminal heterochromatic blocks positively stained with chromomycin A(3) (CMA(+) bands). Some of these blocks are 45S rDNA sites, whereas others may correspond to the main GC-rich satellite DNA found in several Citrus species. In the present work, the distribution of the 45S rDNA and the main satellite DNA isolated from C. sinensis (CsSat) were investigated by in situ hybridization in seven species of Citrus, two species of closely related genera (Fortunella obovata and Poncirus trifoliata) and four species of the subfamily Aurantioideae, which were less related to Citrus (Atalantia monophylla, Murraya paniculata, Severinia buxifolia, and Triphasia trifolia). In Citrus, Fortunella, and Poncirus, most CMA(+) bands colocalized only with CsSat sites, whereas others colocalized only with rDNA sites. However, some of these species displayed a few CMA(+) bands that colocalized with sites of both probes and other CMA(+) bands that did not colocalized with any of the probes. On the other hand, in the four species less related to Citrus, no CsSat signal was found on chromosomes. On Southern blot, the CsSat probe hybridized with genomic DNA from Citrus, Fortunella, and Poncirus at high stringency only, while under the less stringent conditions, it also hybridized with distantly related species. Therefore, CsSat sequences are the principal component of the heterochromatic blocks of Citrus, Poncirus, and Fortunella, whereas CsSat-like sequences seem to be widespread in the subfamily Aurantioideae. These data further suggest that the variable number of terminal CMA(+) bands observed on chromosomes of Citrus and related genera are probably the consequence of amplification or reduction in the number of CsSat-like sequences distributed on chromosome termini, paralleled by mutation and homogenization events, as proposed by the library hypothesis.

  18. Ostryopsis davidiana seedlings inoculated with ectomycorrhizal fungi facilitate formation of mycorrhizae on Pinus tabulaeformis seedlings.

    Science.gov (United States)

    Bai, Shu-Lan; Li, Guo-Lei; Liu, Yong; Kasten Dumroese, R; Lv, Rui-Heng

    2009-08-01

    Reforestation in China is important for reversing anthropogenic activities that degrade the environment. Pinus tabulaeformis is desired for these activities, but survival and growth of seedlings can be hampered by lack of ectomycorrhizae. When outplanted in association with Ostryopsis davidiana plants on reforestation sites, P. tabulaeformis seedlings become mycorrhizal and survival and growth are enhanced; without O. davidiana, pines often remain without mycorrhizae and performance is poorer. To better understand this relationship, we initiated an experiment using rhizoboxes that restricted root and tested the hypothesis that O. davidiana seedlings facilitated ectomycorrhizae formation on P. tabulaeformis seedlings through hyphal contact. We found that without O. davidiana seedlings, inocula of five indigenous ectomycorrhizal fungi were unable to grow and associate with P. tabulaeformis seedlings. Inocula placed alongside O. davidiana seedlings, however, resulted in enhanced growth and nutritional status of O. davidiana and P. tabulaeformis seedlings, and also altered rhizosphere pH and phosphatase activity. We speculate that these species form a common mycorrhizal network and this association enhances outplanting performance of P. tabulaeformis seedlings used for forest restoration.

  19. Feeding ecology of the copepod Lucicutia aff. L. grandis near the lower interface of the Arabian Sea oxygen minimum zone

    Science.gov (United States)

    Gowing, Marcia M.; Wishner, Karen F.

    Feeding ecology of the calanoid copepod Lucicutia aff. L. grandis collected in the Arabian Sea at one station during the Spring Intermonsoon and during the Southwest Monsoon of 1995 was studied with transmission electron microscopy of gut-contents. Highest abundances of these animals occurred from ˜400 to 1100 m, near the lower interface of the oxygen minimum zone and at the inflection point where oxygen starts to increase. We expected that their gut-contents would include particles and cells that had sunk relatively undegraded from surface waters as well as those from within the oxygen minimum zone, and that gut-contents would differ between the Spring Intermonsoon and the more productive SW Monsoon. Overall, in both seasons Lucicutia aff. L. grandis was omnivorous, and consumed a variety of detrital particles, prokaryotic and eukaryotic autotrophs, gram-negative bacteria including metal-precipitating bacteria, aggregates of probable gram-positive bacteria, microheterotrophs, virus-like particles and large virus-like particles, as well as cuticle and cnidarian tissue. Few significant differences in types of food consumed were seen among life stages within or among various depth zones. Amorphous, unidentifiable material was significantly more abundant in guts during the Spring Intermonsoon than during the late SW Monsoon, and recognizable cells made up a significantly higher portion of gut-contents during the late SW Monsoon. This is consistent with the Intermonsoon as a time when organic material is considerably re-worked by the surface water microbial loop before leaving the euphotic zone. In both seasons Lucicutia aff. L. grandis had consumed what appeared to be aggregates of probable gram-positive bacteria, similar to those we had previously found in gut-contents of several species of zooplankton from the oxygen minimum zone in the eastern tropical Pacific. By intercepting sinking material, populations of Lucicutia aff. L. grandis act as a filter for carbon

  20. Inspection and identification of Guignardia citricarpa, the cause of citrus black spot of Citrus grandis in Meizhou Guangdong%广东梅州蜜柚柑橘黑斑病菌的检验鉴定

    Institute of Scientific and Technical Information of China (English)

    胡佳; 王卫芳; 钟国强; 荣晓东; 黄河; 王娟

    2010-01-01

    近年,柑橘黑斑病成为阻碍我国柑橘鲜果出口贸易的瓶颈,广东梅州名优鲜果蜜柚生产基地也遇到类似情况.该病发生后,病果果皮表面产生许多圆形病斑,初呈红褐色,中间凹陷,直径多为23 mm,后期病斑逐渐转为褐色至黑褐色,病斑中部明显可见细小的黑色粒点状分生孢子器.病果分离物的培养性状与形态特征与柑橘黑斑病菌(柑橘球座菌,Guignarida citricarpa)一致.采用真菌TTS通用引物和柑橘球座菌特异性引物,从病斑组织基因组DNA及分离物基因组DNA中分别扩增得到541bp和396bp的片段.BLAST分析表明:扩增到的片段均与GenBank中已知柑橘球座菌菌株的rDNA ITS序列相似性最高,分别为97%和98%.根据分离菌株的培养性状和形态特征及ITS区序列分析结果,将梅州蜜柚上的柑橘黑斑病菌鉴定为柑橘球座菌(Guignarida citricarpa Kiely).

  1. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. proliferatum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected on four locations in Serbia based on symptoms of wilting caused by fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivars K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings, which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown, lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  2. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. prolifera- tum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected at four locations in Serbia based on symptoms of wilting caused by Fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivar K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  3. Morphoanatomy of Serjania communis Cambess. seedling (Sapindaceae

    Directory of Open Access Journals (Sweden)

    Willian Adriano Lira Lopes

    2015-07-01

    Full Text Available Serjania communis Cambess. (Sapindaceae is a plant with climbing habit and occurs relatively often in Paraná State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringá, Paraná State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in length and brown color. Seedlings are epigeal phanerocotylar. The seedlings have a hairy hypocotyl, foliaceous cotyledons, reduced epicotyl, and two opposite eophylls. The root is diarch, the hypocotyl shows root-stem transition structure, stem epicotyl, and dorsiventral and hypostomatous cotyledons and eophylls. 'Tirodendros' with 45 days of age do not develop cambial variant.

  4. High-throughput gene and SNP discovery in Eucalyptus grandis, an uncharacterized genome

    Directory of Open Access Journals (Sweden)

    Pappas Georgios J

    2008-06-01

    Full Text Available Abstract Background Benefits from high-throughput sequencing using 454 pyrosequencing technology may be most apparent for species with high societal or economic value but few genomic resources. Rapid means of gene sequence and SNP discovery using this novel sequencing technology provide a set of baseline tools for genome-level research. However, it is questionable how effective the sequencing of large numbers of short reads for species with essentially no prior gene sequence information will support contig assemblies and sequence annotation. Results With the purpose of generating the first broad survey of gene sequences in Eucalyptus grandis, the most widely planted hardwood tree species, we used 454 technology to sequence and assemble 148 Mbp of expressed sequences (EST. EST sequences were generated from a normalized cDNA pool comprised of multiple tissues and genotypes, promoting discovery of homologues to almost half of Arabidopsis genes, and a comprehensive survey of allelic variation in the transcriptome. By aligning the sequencing reads from multiple genotypes we detected 23,742 SNPs, 83% of which were validated in a sample. Genome-wide nucleotide diversity was estimated for 2,392 contigs using a modified theta (θ parameter, adapted for measuring genetic diversity from polymorphisms detected by randomly sequencing a multi-genotype cDNA pool. Diversity estimates in non-synonymous nucleotides were on average 4x smaller than in synonymous, suggesting purifying selection. Non-synonymous to synonymous substitutions (Ka/Ks among 2,001 contigs averaged 0.30 and was skewed to the right, further supporting that most genes are under purifying selection. Comparison of these estimates among contigs identified major functional classes of genes under purifying and diversifying selection in agreement with previous researches. Conclusion In providing an abundance of foundational transcript sequences where limited prior genomic information existed, this

  5. RNA-Seq reveals complex genetic response to deepwater horizon oil release in Fundulus grandis

    Directory of Open Access Journals (Sweden)

    Garcia Tzintzuni I

    2012-09-01

    Full Text Available Abstract Background The release of oil resulting from the blowout of the Deepwater Horizon (DH drilling platform was one of the largest in history discharging more than 189 million gallons of oil and subject to widespread application of oil dispersants. This event impacted a wide range of ecological habitats with a complex mix of pollutants whose biological impact is still not yet fully understood. To better understand the effects on a vertebrate genome, we studied gene expression in the salt marsh minnow Fundulus grandis, which is local to the northern coast of the Gulf of Mexico and is a sister species of the ecotoxicological model Fundulus heteroclitus. To assess genomic changes, we quantified mRNA expression using high throughput sequencing technologies (RNA-Seq in F. grandis populations in the marshes and estuaries impacted by DH oil release. This application of RNA-Seq to a non-model, wild, and ecologically significant organism is an important evaluation of the technology to quickly assess similar events in the future. Results Our de novo assembly of RNA-Seq data produced a large set of sequences which included many duplicates and fragments. In many cases several of these could be associated with a common reference sequence using blast to query a reference database. This reduced the set of significant genes to 1,070 down-regulated and 1,251 up-regulated genes. These genes indicate a broad and complex genomic response to DH oil exposure including the expected AHR-mediated response and CYP genes. In addition a response to hypoxic conditions and an immune response are also indicated. Several genes in the choriogenin family were down-regulated in the exposed group; a response that is consistent with AH exposure. These analyses are in agreement with oligonucleotide-based microarray analyses, and describe only a subset of significant genes with aberrant regulation in the exposed set. Conclusion RNA-Seq may be successfully applied to feral and

  6. CARACTERÍSTICAS TECNOLÓGICAS DA MADEIRA DE ÁRVORES MATRIZES DE Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Denis L. G. Fernandes

    2004-06-01

    Full Text Available O objetivo do presente trabalho foi caracterizar árvores matrizes de Eucalyptus grandis em relação a características tecnológicas da madeira. Foram selecionadas 63 árvores matrizes, pertencentes a um povoamento comercial localizado no litoral norte do Rio Grande do Sul. As árvores foram abatidas e, com base nos dados dendrométricos, calculou-se o volume comercial com e sem casca, o fator de forma, a conicidade e a relação altura/diâmetro. Quanto à madeira, foi analisada a massa específica básica, os percentuais volumétricos de cerne, alburno e casca, as rachaduras de topo das toras e das tábuas, os empenamentos e os defeitos visuais das tábuas, tais como nós e bolsa de resina. A massa específica básica, cuja média inclui a madeira dessa espécie entre as moderadamente leves a pesadas, mostrou uma tendência decrescente entre o DAP e 25% da altura comercial e, a partir daí, crescente até 100% da mesma. O percentual volumétrico de cerne apresentou valores médios crescentes desde a base até 25% da altura comercial e, a partir daí, diminuiu até 100% da altura comercial, sendo que a média geral foi de 75,7%. O comprimento médio das rachaduras de topo em tábuas de Eucalyptus grandis foi de 63%. A alta porcentagem de rachaduras de topo foi atribuída à posição de retirada das tábuas, próxima à medula. Já a variabilidade das rachaduras de topo encontrada para as toras (CV=60% possibilita a seleção de árvores com menor tendência em apresentar esse defeito.

  7. Effects of Rest Grazing on Organic Carbon Storage in Stipa grandis Steppe in Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    LI Yu-jie; ZHU Yan; ZHAO Jian-ning; LI Gang; WANG Hui; LAI Xin; YANG Dian-lin

    2014-01-01

    This study was aimed to evaluate the potential effects of rest grazing on organic carbon storage in Stipa grandis steppe of Inner Mongolia, China. Using potassium dichromate heating method, we analyzed the organic carbon storage of plant and soil in Stipa grandis steppe after rest grazing for 3, 6, and 9 yr. The results indicated that as the rest grazing ages prolonged, the biomass of aboveground parts, litter and belowground plant parts (roots) of the plant communities all increased, meanwhile the C content of the biomass increased with the rest grazing ages prolonging. For RG0, RG3a, RG6a, and RG9a, C storage in aboveground vegetation were 60.7, 76.9, 82.8 and 122.2 g Cm-2, respectively;C storage of litter were 5.1, 5.8, 20.4 and 25.5 g Cm-2, respectively;C storage of belowground roots (0-100 cm) were 475.2, 663.0, 1 115.0 and 1 867.3 g Cm-2, respectively;C storage in 0-100 cm soil were 13.97, 15.76, 18.60 and 32.41 kg Cm-2, respectively. As the rest grazing ages prolonged, the organic C storage in plant communities and soil increased. The C storage of belowground roots and soil organic C was mainly concentrated in 0-40 cm soil body. The increased soil organic C for RG3a accounted for 89.8% of the increased carbon in vegetation-soil system, 87.2%for RG6a, and 92.6%for RG9a. From the perspective of C sequestration cost, total cost for RG3a, RG6a, and RG9a were 2 903.4, 5 806.8 and 8 710.2 CNY ha-1, respectively. The cost reduced with the extension of rest grazing ages, 0.15 CNY kg-1 C for RG3a, 0.11 CNY kg-1 C for RG6a and 0.04 CNY kg-1 C for RG9a. From the growth characteristics of grassland plants, the spring was one of the two avoided grazing periods, timely rest grazing could effectively restore and update grassland vegetation, and was beneifcial to the sustainable use of grassland. Organic C storage for RG9a was the highest, while the cost of C sequestration was the lowest. Therefore, spring rest grazing should be encouraged because it was proved to be a very

  8. Effect of Endotrophic Fungi on Physiological Characteristics of Eucalyptus urophylla × E.grandis and Soil Properties Under Low Phosphorus Stress%内生真菌对低磷胁迫下尾巨桉生理及土壤特性的影响

    Institute of Scientific and Technical Information of China (English)

    谢安强; 洪伟; 吴承祯; 洪滔; 林勇明

    2013-01-01

    10 strains of eucalyptus endophytic fungi were inoculated into the seedlings of Eucalyptus urophylla × Eucalyptus grandis under low phosphorus stress by irrigating with the fungal solution (11 treatments added control treatment),and the experiment with low phosphorus stress was carried 30 days later.The content of soluble protein was measured 15 d,30 d and 45 d consequently after the inoculation,and the chlorophyll content of the seedling leaves and the chemical properties of soil were measured 3 months later.Compared to the CK group,the results showed that the content of soluble protein of the seedlings inoculated with strain G,strain E and strain J under normal phosphorus supply was increased by 27.82%,23.08% and 6.76% ; Under No.1 low phosphorus stress condition the content of soluble protein of the seedlings inoculated with strain G and strain J was 5.24% and 1.00% higher than that of the CK Under No.2 low phosphorus stress condition,the content of soluble protein of seedlings inoculated with strain J,strain E and strain G was 27.62%,22.52% and 21.95% higher than that of the CK.The total chlorophyll content of the seedlings inoculated with strain J,strain E and strain G was 40.67%,36.60% and 32.69% higher than that of the CK.The soil pH value that growing the seedlings inoculated with strain J,strain E and strain G was 5.07%,4.04% and 1.80% lower than the CK,whereas the content of soil phosphatase that growing the seedlings inoculated with strain J,strain E and strain G was 94.50%,88.83% and 88.83% higher than that of the CK Comprehensively speaking,the fungal strain E,strain G and strain J could significantly promote the contents of soluble protein and chlorophyll of Eucalyptus urophylla × Eucalyptus grandis seedlings,could increase the activity of phosphatase of the soil and improve the phosphorus absorption of the Eucalyptus urophylla × Eucalyptus grandis seedlings.%通过菌液浇施的方法接种10株桉树内生菌

  9. Phenology of Asian citrus psyllid (Hemiptera: Liviidae) and associated parasitoids on two species of Citrus, kinnow mandarin and sweet orange, in Punjab Pakistan.

    Science.gov (United States)

    Khan, Shouket Zaman; Arif, Muhammad Jalal; Hoddle, Christina D; Hoddle, Mark S

    2014-10-01

    The population phenology of Asian citrus psyllid, Diaphorina citri Kuwayama, was monitored weekly for 110 wk on two species of Citrus, kinnow mandarin and sweet orange, at two different research sites in Faisalabad, Punjab Pakistan. Citrus flush growth patterns were monitored and natural enemy surveys were conducted weekly. Flush patterns were similar for kinnow and sweet orange. However, flush on sweet orange was consistently more heavily infested with Asian citrus psyllid than kinnow flush; densities of Asian citrus psyllid eggs, nymphs, and adults were higher on sweet orange when compared with kinnow. When measured in terms of mean cumulative insect or Asian citrus psyllid days, eggs, nymphs, and adults were significantly higher on sweet orange than kinnow. Two parasitoids were recorded attacking Asian citrus psyllid nymphs, Tamarixia radiata (Waterston) and Diaphorencyrtus aligarhensis (Shafee, Alam and Agarwal). The dominant parasitoid species attacking Asian citrus psyllid nymphs on kinnow and sweet orange was T. radiata, with parasitism averaging 26%. D. aligarhensis parasitism averaged 17%. Generalist predators such as coccinellids and chrysopids were collected infrequently and were likely not important natural enemies at these study sites. Immature spiders, in particular, salticids and yellow sac spiders, were common and may be important predators of all Asian citrus psyllid life stages. Low year round Asian citrus psyllid densities on kinnow and possibly high summer temperatures, may, in part, contribute to the success of this cultivar in Punjab where Candidatus Liberibacter asiaticus, the putative causative agent of huanglongbing, a debilitating citrus disease, is widespread and vectored by Asian citrus psyllid.

  10. 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.

  11. Durabilidad natural de madera de Eucalyptus grandis Hill ex Maiden de plantaciones de rápido crecimiento

    Directory of Open Access Journals (Sweden)

    Silvia Böthig

    2011-05-01

    Full Text Available Una de las especies forestales de rápido crecimiento cultivadas en Uruguay de mayor importancia económica es el Eucalyptus grandis. Trabajos anteriores reportan propiedades físicas y mecánicas de la madera juvenil y adulta proveniente de plantaciones de esta especie en diferentes regiones del país. Sin embargo, dado que no se dispone de datos científicos nacionales sobre su durabilidad natural, en este trabajo fue evaluada madera de E. grandis obtenida de dos plantaciones de 16 años de edad con semilla del mismo origen, de dos sitios, Rivera y Río Negro. Se estudió la durabilidad natural del duramen externo e interno siguiendo los métodos de la norma EN 350-1, tomando Populus deltoides x euroamericana cv I-214 como especie de referencia. Se realizaron ensayos de laboratorio para determinar la resistencia a la descomposición fúngica (Gloeophyllum trabeum, Trametes versicolor y Serpula lacrymans y a las termites (Reticulitermes spp. siguiendo las normas EN 113 y EN 118, respectivamente. Se realizaron ensayos de campo de estacas, de doble capa y cámara fúngica, los cuales aún están en curso, por lo que en el presente trabajo se presentan resultados parciales. Los perfiles radiales de densidad básica revelaron que la madera del duramen externo no era adulta, sino madera de transición. En general, el duramen de E. grandis mostró una mayor durabilidad que el híbrido Populus.El E. grandis se clasificó como moderadamente o seriamente atacado por Reticulitermes spp. Según EN 350-1, la madera juvenil de E. grandis puede considerarse como “moderadamente durable” ante la pudrición parda provocada por G. trabeum, mientras que la madera de transición puede describirse como “durable”. La madera de transición mostró en relación a la madera juvenil una mayor resistencia al G. trabeum, una susceptibilidad levemente menor a las termites y mejor desempeño en el campo luego de 17 meses de exposición. El sitio de la plantación no

  12. Morphoanatomy of Serjania communis Cambess. seedling (Sapindaceae)

    OpenAIRE

    2015-01-01

    Serjania communis Cambess. (Sapindaceae) is a plant with climbing habit and occurs relatively often in Paraná State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringá, Paraná State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in l...

  13. Volume de madeira e concentração foliar de nutrientes em parcelas experimentais de Eucalyptus grandis fertilizadas com lodos de esgoto úmido e seco Wood volume and foliar concentration of nutrients in Eucalyptus grandis after wet and dry sewage sludge application

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Muller da Silva

    2008-10-01

    over after wastewater treatment and its disposal needs to be well planned, considering sanitary, environmental, economic and social implications. Sewage sludge (biosolids is high in organic content and plant nutrient and could be applied as fertilizer in forest plantations. The aim of this research, conducted at the Experimental Station of Itatinga (University of São Paulo was to evaluate the effects of increasing doses (10, 20 and 30 tons ha-1 of wet and dry biosolids(pellets, complemented with K and B, and applied to planting rows in experimental Eucalyptus grandis plots 1.5 years after seedling plantation. Trunk volume increased significantly regarding the eucalypt trees that received wet and dry sewage sludge, compared to the control treatment (no fertilization, and a similar growth of eucalypt trees that received full mineral fertilization. Regarding mineral nutrition, a positive correlation was observed between doses of biosolids and P, Ca, and Zn concentrations in the leaves, but a negative effect for Mn and biosolid dose. The foliar concentration of all the nutrients in the biosolid-treated eucalypt trees remained within the limits observed in commercial plantations, with no signs of nutritional imbalance.

  14. 巨桉凋落叶分解对假俭草生长及光合特性的影响%Effects of Eucalyptus grandis leaf litter decomposition on the growth and photosynthetic characteristics of Eremochola ophiuroides

    Institute of Scientific and Technical Information of China (English)

    李羿桥; 李西; 胡庭兴

    2013-01-01

    植物生长的本质是由光能驱动的复杂生理学过程,90%~95%干物质的积累来源于光合产物.本研究采用盆栽试验探讨了巨桉凋落叶分解对假俭草生长及光合特性的影响.4个添加不同凋落叶量的试验组被设置,包括了T1(30 g/盆),T2(60 g/盆),T3(90 g/盆)以及CK(0 g/盆);同时,以添加去除化感物质凋落叶的处理为空白试验.选取晴天测定假俭草光合参数以及在30,60,90 d时的生长指标.结果表明,分解中的巨桉凋落叶明显抑制假俭草的生长、生物量的积累以及光合色素的合成,且随凋落叶含量的增加抑制作用加大;处理组叶片的气孔导度及其对环境中光照和CO2改变的适应能力与对照组相比显著降低(P<0.05).综上,巨桉凋落叶化感作用减弱了假俭草叶片的光合作用,并抑制假俭草的生长.%The essence of crop production is a complex system that is driven by light energy.The accumulation of 90% of the dry matter comes from the production of photosynthesis.In this study,we investigated the effect of Eucalyptus grandis leaf litter decomposition on the growth and photosynthetic characteristics of Eremochola ophiuroides.Four treatments with different amounts of leaf litter were designed,including T1 (30 g/pot),T2 (60 g/pot),T3 (90 g/pot) and control (0 g/pot,CK),and the blank experiment groups with distilled fallen leaves were set as the above.The growth indexes were measured at 30,60 and 90 d after sowing,and the photosynthetic characteristics were tested on the mature leaf in the middle of stolon.The test results showed that increasing amounts of E.grandis leaf litter significantly inhibited the accumulation of biomass,growth,synthesis of photosynthetic pigments of E.ophiuroides seedlings (P<0.05).Meanwhile,the stomatal conductance and the adaptation capacity to the change of light and CO2 in the environment of CK were significantly lower than which of treatments.This demonstrated that the

  15. 巨桉凋落叶分解对菊苣生长及光合特性的影响%Effects of Eucalyptus grandis leaf litter decomposition on the growth and photosynthetic characteristics of Cichorium intybus

    Institute of Scientific and Technical Information of China (English)

    吴秀华; 胡庭兴; 杨万勤; 陈洪; 胡红玲; 涂利华; 泮永祥; 曾凡明

    2012-01-01

    A pot experiment was conducted to study the effects of Eucalyptus grandis leaf litter during its early stage decomposition on the growth and the photosynthesis of Ckhorium intybus. Each pot contained 12 kg soil mixed with different amounts of E. grandis leaf litter (30 g · pot-1, A1; 60 g · pot-1, A2; 90 g · pot-1, A3; and 0 g · pot-1, CK) , and sowed with C. intybus. The growth indicators and the photosynthetic characteristics of C. intybus were measured after the third leaf of C. intybus seedlings fully expanded in treatment A,. At the early stage of leaf litter decomposition , the C. intybus biomass accumulation, leaf area growth, and synthesis of photosynthetic pigments were inhibited significantly, and the inhibition effect was getting stronger with the increasing amount of the leaf litter addition. The intercellular CO2 concentration of C. intybus was increased by litter addition, while the net photosynthetic rate, stomatal conductance, and transpiration rate were significantly lower than those of the control. With the increase of leaf litter addition, all the parameters of C. intybus light response and CO2 response except CO2 compensation point showed an obvious downward trend, and there existed significant differences between the treatments of litter additions and the control. It was suggested that during the decomposition of E. grandis leaf litter, its al-lelopathic substances released gradually and acted on receptor plants, inhibited the synthesis of photosynthetic pigments and the photosynthesis of the receptors, decreased the receptors environmental adaptation ability, and accordingly, inhibited the growth of C. intybus.%采用盆栽试验,研究了巨桉凋落叶分解初期对菊苣幼苗生长和光合生理特性的影响,试验设置A1(30 g·pot-1)、A2(60 g·pot-1)、A3 (90 g·pot-1)和对照(CK)4个凋落叶水平,将各处理的凋落叶分别与12 kg土壤混合后装盆,播种菊苣.待A3处理植株的第3片真叶完全展开后测定

  16. Large changes in anatomy and physiology between diploid Rangpur lime (Citrus limonia) and its autotetraploid are not associated with large changes in leaf gene expression.

    Science.gov (United States)

    Allario, Thierry; Brumos, Javier; Colmenero-Flores, Jose Manuel; Tadeo, Francisco; Froelicher, Yann; Talon, Manuel; Navarro, Luis; Ollitrault, Patrick; Morillon, Raphaël

    2011-05-01

    Very little is known about the molecular origin of the large phenotypic differentiation between genotypes arising from somatic chromosome set doubling and their diploid parents. In this study, the anatomy and physiology of diploid (2x) and autotetraploid (4x) Rangpur lime (Citrus limonia Osbeck) seedlings has been characterized. Growth of 2x was more vigorous than 4x although leaves, stems, and roots of 4x plants were thicker and contained larger cells than 2x that may have a large impact on cell-to-cell water exchanges. Leaf water content was higher in 4x than in 2x. Leaf transcriptome expression using a citrus microarray containing 21 081 genes revealed that the number of genes differentially expressed in both genotypes was less than 1% and the maximum rate of gene expression change within a 2-fold range. Six up-regulated genes in 4x were targeted to validate microarray results by real-time reverse transcription-PCR. Five of these genes were apparently involved in the response to water deficit, suggesting that, in control conditions, the genome expression of citrus autotetraploids may act in a similar way to diploids under water-deficit stress condition. The sixth up-regulated gene which codes for a histone may also play an important role in regulating the transcription of growth processes. These results show that the large phenotypic differentiation in 4x Rangpur lime compared with 2x is not associated with large changes in genome expression. This suggests that, in 4x Rangpur lime, subtle changes in gene expression may be at the origin of the phenotypic differentiation of 4x citrus when compared with 2x.

  17. Overexpression of citrus polygalacturonase-inhibiting protein in citrus black rot pathogen Alternaria citri.

    Science.gov (United States)

    Katoh, Hiroshi; Nalumpang, Sarunya; Yamamoto, Hiroyuki; Akimitsu, Kazuya

    2007-05-01

    The rough lemon (Citrus jambhiri) gene encoding polygalacturonase-inhibiting protein (RlemPGIPA) was overexpressed in the pathogenic fungus Alternaria citri. The overexpression mutant AcOPI6 retained the ability to utilize pectin as a sole carbon source, and the overexpression of polygalacturonase-inhibiting protein did not have any effect on the growth of AcOPI6 in potato dextrose and pectin medium. The pathogenicity of AcOPI6 to cause a black rot symptom in citrus fruits was also unchanged. Polygalacturonase-inhibiting protein was secreted together with endopolygalacturonase into culture filtrates of AcOPI6, and oligogalacturonides were digested from polygalacturonic acid by both proteins in the culture filtrates. The reaction mixture containing oligogalacturonides possessed activity for induction of defense-related gene, RlemLOX, in rough lemon leaves.

  18. 柑橘木虱对柑橘不同品种的趋性%Diaphorina citri's Gost Preference on Thirteen Citrus Varieties

    Institute of Scientific and Technical Information of China (English)

    陈建利; 阮传清; 刘波; 范国成; 段永平; D.HALL

    2011-01-01

    用2种方法测定了柑橘木虱Diaphorina citri Kuw.成虫对13个柑橘品种离体嫩梢的选择性.结果表明,对不同品种进行两两组合的选择性试验,柑橘木虱停靠在处理组合早金和四季斑叶橘的虫量占总虫量的23%和1%,停靠在处理组合台湾玫瑰橙和纽荷尔脐橙上的虫量分别占总虫量的33%和20%,停靠在处理组合日辉和佩奇甜橙上虫量分别占总虫量的38%和15%,两两之间差异显著.将13个品种组合在一起进行选择性试验,结果表明柑橘木虱停靠在纽荷尔、福橘和佩奇甜橙上的成虫数量为每梢3.2~6.6只·d-1,显著高于木虱在其余10个品种枝梢上的停靠数量.福橘是柑橘黄龙病高发品种的原因是其对柑橘木虱的吸引力较强.%Under laboratory conditions, preference of adult Asian Citrus Psyllid (ACP), Diaphorina citri Kuw, for infestation among 13 citrus varieties was determined with two experimentations. Experiment A applied every 2 detached shoots of different citrus varieties and put together for choice. Experiment B used the detached shoots of all tested citrus varieties and put together for choice. The results of Experiment A revealed that the percentage of ACP adults on each shoot of Citrus sinensis (L.) Osbeck cv. Earlygold and C. medurensis (C. mitis) cv. Varigated Calamondin were 23 % and 1 %, respectively, which was significantly different from each other. The percentage on C. sinensis Osbeck cv. Taiwanmeiguicheng (33%) and cv. Newhall Navel Orange (20%) were also significantly different from each other. Significant different percentages of ACP adults were also observed between C. reticulata C. paradisi cv. Rihui (38%) and C. reticulata C. grandis cv. Page (15%). In Experiment B, the number of ACP on the shoots of C. sinensis Osbeck cv. Newhall Navel Orange, C. tangerina Tanaka cv. Fuju and C. reticulata Citrusgrandis cv. Page was 3.2-6.6 adults · shoot-day-1 , which were significantly higher than that

  19. Structure and Function of the Digestive System of Solen Grandis Dunker

    Institute of Scientific and Technical Information of China (English)

    SHENG Xiuzhen; ZHAN Wenbin; REN Sulian

    2003-01-01

    Structure and function of the digestive system of a bivalve mollusc, Solen grandis, were studied using light microscopy and histochemical methods. The wall of digestive tube consists of four layers: the mucosal epithelium, connective tissue, muscular and fibrosa or serosa (only in the portion of rectum) from the inner to the outer. The ciliated columnar epithelial cells, dispersed by cup-shaped mucous cells, rest on a thin base membrane. There are abundant blood spaces in connective tissue layer. The digestive diverticula are composed of multi-branched duct and digestive tubules. The digestive tubules are lined with digestive and basophilic secretory cells, and surrounded by a layer of smooth muscle fibers and connective tissues. Activities of acid and alkaline phosphatases, esterase and lipase are detected in the digestive cells, and the epithelia of stomach and intestine, suggesting that these cells are capable of intracellular digesting of food materials and absorbing.Besides, acid phosphatase and esterase activities are present in the posterior portion of esophagus. Phagocytes are abundant in blood spaces and the lumens of stomach and intestine, containing brown granules derived from the engulfed food materials. The present work indicates that phagocytes play important roles in ingestion and digestion of food materials, which is supported as well by the activities of acid phosphatase, esterase and lipase detected in blood spaces.

  20. Química e colorimetria da madeira de Eucalyptus grandis W. Mill ex Maiden termorretificada

    Directory of Open Access Journals (Sweden)

    Antônio José Vinha Zanuncio

    2014-08-01

    Full Text Available A termorretificação visa melhorar as características para agregar valor à madeira através da aplicação de calor. O objetivo foi avaliar as alterações químicas e colorimétricas da madeira termorretificada de Eucalyptus grandis submetida a 170, 200 e 230 ºC por 3, 5 e 7 h. Os teores de extrativos, lignina, holocelulose, composição elementar e os parâmetros colorimétricos foram determinados. Os teores de extrativos aumentaram nos tratamentos a 170 °C e diminuíram a partir de 200 °C, enquanto o teor de lignina total aumentou e o de holocelulose diminuiu a partir de 200 °C. O teor de carbono aumentou e o de oxigênio diminuiu a 230 °C por 5 e 7 h. A termorretificação reduziu a claridade, matriz vermelho (a* e matriz amarelo (b* da madeira de eucalipto em todos os tratamentos.

  1. EFEITO DO DESBASTE NAS RACHADURAS DE TOPO DAS TORAS DE Eucalyptus grandis W. Hill ex Maiden

    Directory of Open Access Journals (Sweden)

    Rômulo Trevisan

    2014-01-01

    Full Text Available The study was undertaken to evaluate the effect of thinning in the end splits of the logs of the Eucalyptus grandis at 18 years of age. There was analyzed a thinning experiment, located in the northern coast of Rio Grande do Sul State, Brazil, installed in randomized blocks with four repetitions. The seven treatments were defined according to the number of thinnings applied and ranged from zero to six interventions. The trees were selected, in each treatment, on the basis of the Assmann’s dominant diameter and the central diameter of tree, being referred to as dominant and central trees, respectively. After cutting down the selected the logs were located between the DBH (diameter at breast height and 25% positions, 25% and 50%; 50% and 75%; 75% and 100% of the commercial height, for the end split study. The results indicate that the average end splits of the logs in the dominant and central trees was higher at the second log sampled, suggesting that sectioning should be carried in conjunction with techniques that minimize the growth stress, especially when this is performed near the half of the commercial height. The thinning induced variation in the logs end split, both for dominant and central trees; however, there was no clear positive or negative trend, leading to the conclusion that changes in growth rate did not af fect these parameters uniformly.

  2. LOG BREAKDOWN OF Eucalyptus grandis WITH CHAINSAW, PART 1 – OPERATIONAL PERFORMANCE ANALYSISi

    Directory of Open Access Journals (Sweden)

    Djeison Cesar Batista

    2013-08-01

    Full Text Available http://dx.doi.org/10.5902/1980509810558The aim of this work was to analyze the operational performance of chainsaw log breakdown of Eucalyptus grandis W.Hill, taking into account small scale use, e.g., in small farms, using yield and efficiency as evaluation tools. The specific aim was to analyze the behavior of yield and efficiency in five diametric classes: 20.0-25.9cm, 26.0-28.9 cm, 29.0-31.9 cm, 32.0-34.9 cm and 35.0-41.0 cm. According to the results obtained, the chainsaw log breakdown had a satisfactory operational behavior, with average yield and efficiency of 58,5% and 0.55m³/operator/h, respectively. However, the feasibility of such technique is restricted to small scale use. Diametric class 3 (29.0-31.9 cm presented the best yield (66.6% because it was the one that presented the best adequacy between log diameter and products. It is suggested for further researches the development of specific sawing diagrams per diametric class, in addition to the reduction of class ranges, aiming the yield increase. The average breakdown time spent per log was the same for classes 3, 4 and 5, resulting that the latter presented the best efficiency, 0.82 m³/operator/h.

  3. Applying Sewage Sludge to Eucalyptus grandis Plantations: Effects on Biomass Production and Nutrient Cycling through Litterfall

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Müller da Silva

    2011-01-01

    Full Text Available In most Brazilian cities sewage sludge is dumped into sanitary landfills, even though its use in forest plantations as a fertilizer and soil conditioner might be an interesting option. Sewage sludge applications might reduce the amounts of mineral fertilizers needed to sustain the productivity on infertile tropical soils. However, sewage sludge must be applied with care to crops to avoid soil and water pollution. The aim of our study was to assess the effects of dry and wet sewage sludges on the growth and nutrient cycling of Eucalyptus grandis plantations established on the most common soil type for Brazilian eucalypt plantations. Biomass production and nutrient cycling were studied over a 36-month period in a complete randomized block design. Four experimental treatments were compared: wet sewage sludge, dry sludge, mineral fertilizer, and no fertilizer applications. The two types of sludges as well as mineral fertilizer increased significantly the biomass of Eucalyptus trees. Wood biomass productions 36 months after planting were similar in the sewage sludge and mineral fertilization treatments (about 80 tons ha−1 and 86% higher than in the control treatment. Sewage sludge application also affected positively leaf litter production and significantly increased nutrient transfer among the components of the ecosystem.

  4. Fractionation of Eucalyptus grandis chips by dilute acid-catalysed steam explosion.

    Science.gov (United States)

    Emmel, Alexandre; Mathias, Alvaro L; Wypych, Fernando; Ramos, Luiz P

    2003-01-01

    Steam explosion of Eucalyptus grandis has been carried out under various pretreatment conditions (200-210 degrees C, 2-5 min) after impregnation of the wood chips with 0.087 and 0.175% (w/w) H2SO4. This study, arranged as a 2(3) factorial design, indicated that pretreatment temperature is the most critical variable affecting the yield of steam-treated fractions. Pretreatment of 0.175% (w/w) H2SO4-impregnated chips at 210 degrees C for 2 min was the best condition for hemicellulose recovery (mostly as xylose) in the water soluble fraction, reaching almost 70% of the corresponding xylose theoretical yield. By contrast, lower pretreatment temperatures of 200 degrees C were enough to yield steam-treated substrates from which a 90% cellulose conversion was obtained in 48 h, using low enzyme loadings of a Celluclast 1.5 1 plus Novozym 188 mixture (Novo Nordisk). Release of water-soluble chromophores was monitored by UV spectroscopy and their concentration increased with pretreatment severity. The yield of alkali-soluble lignin increased at higher levels of acid impregnation and pretreatment temperatures. Thermoanalysis of these lignin fractions indicated a pattern of lignin fragmentation towards greater pretreatment severities but lignin condensation prevailed at the most drastic pretreatment conditions.

  5. Probability density functions for description of diameter distribution in thinned stands of Tectona grandis

    Directory of Open Access Journals (Sweden)

    Julianne de Castro Oliveira

    2012-06-01

    Full Text Available The objective of this study was to evaluate the effectiveness of fatigue life, Frechet, Gamma, Generalized Gamma, Generalized Logistic, Log-logistic, Nakagami, Beta, Burr, Dagum, Weibull and Hyperbolic distributions in describing diameter distribution in teak stands subjected to thinning at different ages. Data used in this study originated from 238 rectangular permanent plots 490 m2 in size, installed in stands of Tectona grandis L. f. in Mato Grosso state, Brazil. The plots were measured at ages 34, 43, 55, 68, 81, 82, 92, 104, 105, 120, 134 and 145 months on average. Thinning was done in two occasions: the first was systematic at age 81months, with a basal area intensity of 36%, while the second was selective at age 104 months on average and removed poorer trees, reducing basal area by 30%. Fittings were assessed by the Kolmogorov-Smirnov goodness-of-fit test. The Log-logistic (3P, Burr (3P, Hyperbolic (3P, Burr (4P, Weibull (3P, Hyperbolic (2P, Fatigue Life (3P and Nakagami functions provided more satisfactory values for the k-s test than the more commonly used Weibull function.

  6. WOOD BASIC DENSITY EFFECT OF Eucalyptus grandis x Eucalyptus urophylla CLONES ON BLEACHED PULP QUALITY

    Directory of Open Access Journals (Sweden)

    Sheila Rodrigues dos Santos

    2010-08-01

    Full Text Available The study analyzed the wood basic density effect in two Eucalyptus grandis x Eucalyptus urophylla hybrid clones (440 kg/m3 e 508 kg/m3 on bleached pulp quality (fiber dimensions and physical-mechanical properties. The woods performance on pulping, bleaching and beating results were analyzed. The Kraft pulping was carried out in forced circulation digester in order to obtain 17±1 kappa number targets. The pulps were bleached to 90±1 using delignification oxygen and D0EOPD1 bleaching sequence. Bleached pulp of low basic density clone showed, significantly, lowest revolutions number in the PFI mill to reach tensile index of 70 N.m/g, low Schopper Riegler degree and generated sheets with higher values to bulk and opacity. These characteristics and properties allow concluding that bleached pulp of low basic density clone was the most indicated to produce printing and writing sheets. The bleached pulp of high basic density clone showed higher values of bulk and capillarity Klemm and lower water retention value when analyzed without beating. The bleached pulp of high basic density clone showed more favorable characteristics to the production of tissue papers.

  7. SCREENING OF ANTIMICROBIAL, CYTOTOXIC AND PESTICIDAL ACTIVITIES OF COCCINIA GRANDIS (L. VOIGT

    Directory of Open Access Journals (Sweden)

    Md. Faruk Hasan

    2016-06-01

    Full Text Available This study was undertaken to assess the antibacterial, antifungal, cytotoxic and pesticidal activities of Coccinia grandis roots extract. The antimicrobial activity was evaluated using disc diffusion method against some pathogenic microorganisms. Cytotoxicity was determined using brine shrimp lethality bioassay method. The plant extract was screened for pesticidal activity towards Sitophilus oryzae adults. Minimum inhibitory concentration (MIC was also studied against test organisms, using serial dilution technique to determine the antibacterial potency. In antibacterial screening, large inhibition zones were observed against the tested gram-positive (Bacillus subtilis, Sarcina lutea and Stapphylococcus aureus and gram-negative (Salmonella typhi and Shigella dysenteriae bacteria. In antifungal screening, the extract showed moderate antifungal activities against the tested fungi (Candida albicans and Colletotrichum falcatum. In cytotoxicity activity test, LC50 (lethal concentration, 50% of the extract against brine shrimp nauplii was 15.00µg/ml. The plant extract also showed moderate pesticidal activities towards S. oryzae adults. These results suggested that the plant extract has significant antibacterial activity against the tested bacteria, moderate antifungal, cytotoxic and pesticidal activity towards the tested fungi, brine shrimp nauplii and S. oryzae adults, respectively.

  8. Características de vigas laminadas coladas confeccionadas com madeira de teca (Tectona grandis

    Directory of Open Access Journals (Sweden)

    Setsuo Iwakiri

    Full Text Available O objetivo desta pesquisa foi avaliar a influência do adesivo, das gramaturas e dos tempos de prensagem nas propriedades mecânicas de vigas laminadas coladas, confeccionadas com madeira de teca (Tectona grandis. As vigas foram produzidas com cinco lamelas, sendo duas da classe de módulo de elasticidade dinâmico, classe 1 - MOEd C1 nas faces, e três da classe 2 - MOEd C2 no miolo. Para a colagem, utilizou-se o adesivo à base de resorcina-fenol-formaldeído (RFF, com gramaturas de 350 e 450 g.m- 2, e tempos de prensagem de 5 e 8 horas. Para o adesivo à base de emulsão polimérica de isocianato (EPI, a colagem foi realizada com gramaturas de 180 e 220 g.m- 2, e tempos de prensagem de 3 e 4 horas. Os resultados das propriedades mecânicas das vigas indicaram que não houve uma relação bem definida dos efeitos das variáveis de estudo nas propriedades de flexão estática. As vigas coladas com o adesivo RFF tiveram maior resistência da linha de cola em comparação às vigas coladas com o adesivo EPI.

  9. Métodos de captura para formigas em pré-plantio de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Jardel Boscardin

    Full Text Available O presente trabalho objetivou avaliar três métodos de coleta de formigas em uma área de pré-plantio de Eucalyptus grandis em Santa Maria-RS. Foram realizadas amostragens de março a agosto de 2011, utilizando-se armadilha de solo (AS, isca atrativa à base de patê de fígado de frango (IA e extração por Funil de Berlese (FB, sendo seis repetições por tratamento em cada data de coleta. Os tratamentos constituíram-se da aplicação de glifosato, tendo sido realizados controles das plantas infestantes: na linha e na entrelinha de plantio (T1; em faixa de um metro paralela à linha de plantio e de um metro na parte central da entrelinha, sem controle (T2; em faixa de meio metro paralela à linha de plantio (T3, e a testemunha, sem controle de plantas infestantes (T4. A partir dos resultados obtidos, os métodos demonstraram ser complementares entre si, sugerindo a utilização de mais de um método na captura de formigas.

  10. PARTICLEBOARDS PRODUCED WITH Eucalyptus grandis W. Hill ex Maiden POLYSTYRENE AND POLYETHYLENE THEREPHTHALATE PARTICLES

    Directory of Open Access Journals (Sweden)

    Antônio da Silva Maciel

    2004-06-01

    Full Text Available This research investigated the properties of wood particleboards, containing particles of polystyrene (PS and polyethylene therephthalate (PET. Particleboards were produced with 0%, 25% or 50% of polystyrene and 100%, 75% or 50% of Eucalyptus grandis particles. Additional boards were produced with two amounts of PET/PS (5/20% or 10/40% and 75% or 50% wood particles. As binding agents three amounts (0%, 4% or 6% of urea-formaldehyde or phenol-formaldehyde adhesive and three amounts of polystyrene in toluene solution (0%, 4% or 6% were used. One-layer boards, measuring approximately 400,0 x 400,0 x 10,0 mm with density approximately equal to 0,60 g/cm3, were produced. Internal bond, modulus of rupture and elasticity, screw withdrawal, as well water absorption and thickness swelling, after 24 hours of immersion were determined. All mechanical boards’ properties were superior to the established by ANSI/A 208.1-1993 standards. All wood/plastic particleboards absorbed more water then those observed in commercial boards. However the observed thickness swelling was quite similar to the values of commercial wood particleboards. Boards in which the solution of polystyrene was applied were, in general, presented the best values for all properties.

  11. Genetic diversity of teak (Tectona grandis L.F. from different provenances using microsatellite markers

    Directory of Open Access Journals (Sweden)

    Berenice Kussumoto Alcântara

    2013-08-01

    Full Text Available Teak (Tectona grandis is one of the main timber species in the world with high economic value, famous for its beauty, strength and durability. The objective of this work was to characterize the genetic diversity of teak genotypes used in Brazilian plantations. Nine microsatellite primers were used to assess 60 teak genotypes, including 33 genotypes from seeds of plantations and 14 clones from Cáceres municipality, Mato Grosso State, Brazil, and 13 clones from Honduras, Malaysia, India, Indonesia, Ivory Coast and Solomon Islands. Two groups of genotypes were detected using the Bayesian Structure analysis: 80% were placed in group 1, represented by genotypes from Cáceres and one from Malaysia, and 20% allocated in group 2, composed of clones from India, Solomon Islands, Malaysia and Honduras and the clones from the Ivory Coast. Most of the genetic variability (73% was concentrated within groups according to AMOVA analysis. Genetic parameters were estimated for the two groups obtained in the analysis of Structure. Moderate genetic diversity was found, with 4.1 alleles per locus, on average, and an average heterozygosity of 0.329, which was lower than the expected heterozygosity (He = 0.492. Group 1 showed the lowest values for these parameters. Suggestions were made concerning the identification of contrasting genotypes to be used as parents in breeding programs.

  12. Hygroscopicity of wood from Eucalyptus grandis and Pinus taeda subjected to thermal treatment

    Directory of Open Access Journals (Sweden)

    Karina Soares Modes

    2013-03-01

    Full Text Available This study aimed to investigate the effect of the thermal treatment technique under two conditions—autoclave combined with electric oven and electric oven only—on the hygroscopic properties of wood from Pinus taeda L. and Eucalyptus grandis W. Hill ex Maiden, comparing them with results obtained for untreated wood. Three trees at age 25 years were sampled, with boards being removed at DBH level in order to make specimens 2.5 x 2.5 x 5.0 cm in size in the radial, tangential and axial direction respectively. In the combined treatment, specimens were subjected to thermal treatment in an autoclave set at 130°C/± 3°C and kgf/cm² pressure for 3 hours, then to a conditioning period, followed by heat in an electric oven set at 160°C/±1°C for the same time. Properties being evaluated included water absorption rate, volumetric swelling, water repellency effectiveness and anti-swelling efficiency. Results revealed that the thermal treatments being adopted were effective in reducing hygroscopicity and in increasing the dimensional stability of both species, revealing also that the combined autoclave and electric oven treatment provides best results.

  13. EFFECT OF LOG STEAMING ON THE REDUCTION OF DEFECTS ASSOCIATED WITH GROWTH STRESS OF Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Fred Willians Calonego

    2010-08-01

    Full Text Available The present study was carried out to evaluate log steaming effect on the reduction of defects associated with residual growth stress of Eucalyptus grandis wood. There were used logs with diameter of 20 to <25, 25 to <30 and 30 to <35 cm, from the Horto Florestal, Manduri, São Paulo. Half of the logs was steamed during 20 hours at 90ºC of temperature and 100% of relative humidity. Subsequently, the logs were live sawn and the defects resulting from the growth stresses in logs of various diameter were measured. The results indicate that log steaming provided the release of a great part of the growth stresses, without eliminating them completely, showing, nevertheless, that this treatment is feasible and advisable for growth stress relief; the boards coming from heated logs of 20 to <25 cm presented, in general, larger defect reduction, showing that the smaller the log diameter the higher the efficiency of steam treatment at 90ºC of temperature during 20 hours.

  14. The GC/MS Analysis of Volatile Components Extracted by Different Methods from Exocarpium Citri Grandis

    Directory of Open Access Journals (Sweden)

    Zhisheng Xie

    2013-01-01

    Full Text Available Volatile components from Exocarpium Citri Grandis (ECG were, respectively, extracted by three methods, that is, steam distillation (SD, headspace solid-phase microextraction (HS-SPME, and solvent extraction (SE. A total of 81 compounds were identified by gas chromatography-mass spectrometry including 77 (SD, 56 (HS-SPME, and 48 (SE compounds, respectively. Despite of the extraction method, terpenes (39.98~57.81% were the main volatile components of ECG, mainly germacrene-D, limonene, 2,6,8,10,14-hexadecapentaene, 2,6,11,15-tetramethyl-, (E,E,E-, and trans-caryophyllene. Comparison was made among the three methods in terms of extraction profile and property. SD relatively gave an entire profile of volatile in ECG by long-time extraction; SE enabled the analysis of low volatility and high molecular weight compounds but lost some volatiles components; HS-SPME generated satisfactory extraction efficiency and gave similar results to those of SD at analytical level when consuming less sample amount, shorter extraction time, and simpler procedure. Although SD and SE were treated as traditionally preparative extractive techniques for volatiles in both small batches and large scale, HS-SPME coupled with GC/MS could be useful and appropriative for the rapid extraction and qualitative analysis of volatile components from medicinal plants at analytical level.

  15. Optimum extraction process of polyphenols from Bridelia grandis stem bark using experimental design.

    Science.gov (United States)

    Brusotti, Gloria; Ngueyem, Tatiana Adrienne; Biesuz, Raffaela; Caccialanza, Gabriele

    2010-06-01

    Euphorbiaceae barks are known to contain an appreciable amount of polyphenolic compounds responsible for several biological activities. Preliminary extraction from Bridelia grandis stem bark afforded high content of polyphenols, determined by spectrophotometric methods such as Folin-Ciocalteu (for total phenols, TP) and n-butanol-HCl (for condensed tannins, CT). A preliminary Plackett-Burman screening design was used to identify the key factors that influence the TP and CT extraction. Between all the variables known to influence the extraction from vegetable matrixes, six were selected; maceration was chosen as traditional extraction methodology. To investigate the effect of solvents and extraction method, methanol, acetone 70% (v/v in water), centrifugation and ultrasound were chosen. A full factorial design 2(3) was applied to optimize the extraction procedure. The responses were obtained analyzing the extracts for their TP and CT contents determined by the above-mentioned spectrophotometric methods. The results confirm that, within the explored domain, the optimum solvent is methanol and the optimum method is one-cycle centrifugation. Finally, it was also compared with the effect of maceration on the considered responses. It has never given results better than centrifugation, whereas in the case of CT it represents an advantage to employ a three-cycle centrifugation instead of one.

  16. RELATIONSHIP BETWEEN THE ANATOMY AND DRYING IN Eucalyptus grandis X Eucalyptus urophylla WOOD

    Directory of Open Access Journals (Sweden)

    Antônio José Vinha Zanuncio

    Full Text Available ABSTRACT Drying is an important step to using wood and anatomical characteristics influence this process. Thus, the objective of this work was to evaluate the relationship between anatomy and wood drying. Samples with 2 x 2 x 4 cm were obtained from eight Eucalyptus urophylla x Eucalyptus grandis clones at 1.3 m height to evaluate the anatomy and drying in climate chamber during 15 days. Cell wall fraction was established as the parameter that best correlated with drying, the Pearson correlation coefficient between this parameter and moisture was -0.8986, -0.6580, 0.9216, 0.8743, 0.7131 and 0.8727 for saturated wood, and after 1, 2.5, 5, 10 and 15 days of drying, respectively. The frequency and vessel size, as well as the height and width of the rays showed low relation with wood drying. Wood anatomy, mainly the cell wall fraction, influences moisture losses and should be considered in wood drying programs.

  17. The antimicrobial effects of Citrus limonum and Citrus aurantium essential oils on multi-species biofilms

    Directory of Open Access Journals (Sweden)

    Sarah Almeida Coelho Oliveira

    2014-01-01

    Full Text Available The aim of this study was to evaluate the effects of Citrus limonum and Citrus aurantium essential oils (EOs compared to 0.2% chlorhexidine (CHX and 1% sodium hypochlorite (NaOCl on multi-species biofilms formed by Candida albicans, Enterococcus faecalis and Escherichia coli. The biofilms were grown in acrylic disks immersed in broth, inoculated with microbial suspension (106 cells/mL and incubated at 37°C / 48 h. After the biofilms were formed, they were exposed for 5 minutes to the solutions (n = 10: C. aurantium EO, C. limonum EO, 0.2% CHX, 1% NaOCl or sterile saline solution [0.9% sodium chloride (NaCl]. Next, the discs were placed in sterile 0.9% NaCl and sonicated to disperse the biofilms. Tenfold serial dilutions were performed and the aliquots were seeded onto selective agar and incubated at 37°C / 48 h. Next, the number of colony-forming units per milliliter was counted and analyzed statistically (Tukey test, p ≤ 0.05. C. aurantium EO and NaOCl inhibited the growth of all microorganisms in multi-species biofilms. C. limonum EO promoted a 100% reduction of C. albicans and E. coli, and 49.3% of E. faecalis. CHX was less effective against C. albicans and E. coli, yielding a reduction of 68.8% and 86.7%, respectively. However, the reduction of E. faecalis using CHX (81.7% was greater than that obtained using C. limonum EO. Both Citrus limonum and Citrus aurantium EOs are effective in controlling multi-species biofilms; the microbial reductions achieved by EOs were not only similar to those of NaOCl, but even higher than those achieved by CHX, in some cases.

  18. Anti-inflammatory effects of Citrus sinensis L., Citrus paradisi L. and their combinations.

    Science.gov (United States)

    Khan, Rafeeq Alam; Mallick, Neelam; Feroz, Zeeshan

    2016-05-01

    Citrus bioflavonoids embrace a wide group of phenolic compounds effecting the production and scavenging of reactive oxygen species and the processes relating free radical-mediated injury. Keeping in view of the antioxidant and anti-inflammatory properties of Citrus sinensis and Citrus paradisi, present study was undertaken to explore the effects of C. sinensis (orange juice) and C. paradisi (grapefruit juice) at three different doses alone and their two combinations with the objective to examine the effects of these compounds in an experimental model of rat colitis induced by trinitrobenzenesulphonic acid (TNBS). Hence biochemical parameters e.g. myeloperoxidase, alkaline phosphatase, C-reactive protein (CRP) and glutathione were assessed. Data entry and analysis was accomplished by Statistical Package for the Social Sciences version 17 and was presented as mean ± S.E.M with 95% confidence interval. Present result shows that these juices, mainly C. paradisi, may be efficacious for the management of inflammatory bowel disease. In acute colitis model, C. paradise encouraged a decrease in the extension of the lesion escorted by a decrease in the occurrence of diarrhea and reinstatement of the glutathione content. Related effects were produced by the administration of C. sinensis, which also prevented the myeloperoxidase and alkaline phosphatase actions in acute intestinal inflammatory process. The effect of the citrus juices on the inflammatory process may be associated to their antioxidant and anti-inflammatory properties, as revealed in present investigation. The favorable effects exerted were demonstrated both by histological and biochemical changes and were related with a progress in the colonic oxidative status.

  19. The draft genome of sweet orange (Citrus sinensis).

    Science.gov (United States)

    Xu, Qiang; Chen, Ling-Ling; Ruan, Xiaoan; Chen, Dijun; Zhu, Andan; Chen, Chunli; Bertrand, Denis; Jiao, Wen-Biao; Hao, Bao-Hai; Lyon, Matthew P; Chen, Jiongjiong; Gao, Song; Xing, Feng; Lan, Hong; Chang, Ji-Wei; Ge, Xianhong; Lei, Yang; Hu, Qun; Miao, Yin; Wang, Lun; Xiao, Shixin; Biswas, Manosh Kumar; Zeng, Wenfang; Guo, Fei; Cao, Hongbo; Yang, Xiaoming; Xu, Xi-Wen; Cheng, Yun-Jiang; Xu, Juan; Liu, Ji-Hong; Luo, Oscar Junhong; Tang, Zhonghui; Guo, Wen-Wu; Kuang, Hanhui; Zhang, Hong-Yu; Roose, Mikeal L; Nagarajan, Niranjan; Deng, Xiu-Xin; Ruan, Yijun

    2013-01-01

    Oranges are an important nutritional source for human health and have immense economic value. Here we present a comprehensive analysis of the draft genome of sweet orange (Citrus sinensis). The assembled sequence covers 87.3% of the estimated orange genome, which is relatively compact, as 20% is composed of repetitive elements. We predicted 29,445 protein-coding genes, half of which are in the heterozygous state. With additional sequencing of two more citrus species and comparative analyses of seven citrus genomes, we present evidence to suggest that sweet orange originated from a backcross hybrid between pummelo and mandarin. Focused analysis on genes involved in vitamin C metabolism showed that GalUR, encoding the rate-limiting enzyme of the galacturonate pathway, is significantly upregulated in orange fruit, and the recent expansion of this gene family may provide a genomic basis. This draft genome represents a valuable resource for understanding and improving many important citrus traits in the future.

  20. Citrus phytophtorose in humid subtropical zone of West Georgia

    Directory of Open Access Journals (Sweden)

    Mziuri Gabaidze

    2015-05-01

    Full Text Available Materials about harmfulness of phytophtorose, which is one of the significant disease of citrus, its spread, time of emergency and effective means of its control are given in the article.

  1. Ethno medicinal values of Citrus genus: A review

    Directory of Open Access Journals (Sweden)

    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.

  2. 2004 SWFWMD Citrus County Bare-Earth 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...

  3. Citrus residues isolates improve astaxanthin production by Xanthophyllomyces dendrorhous.

    Science.gov (United States)

    Wu, Wei; Lu, Mingbo; Yu, Longjiang

    2010-01-01

    The wild strain and two astaxanthin-overproducing mutant strains, W618 and GNG274, of Xanthophyllomyces dendrorhous were analyzed in order to assess their ability to grow and synthesize astaxanthin in a minimal medium containing (per liter): 2 g KH2PO4, 0.5 g MgSO4, 2 g KNO3, and 1 g yeast extract, and supplemented with citrus residues isolates as a carbon source (citrus medium). The selected strain W618 was evaluated under various contents of citrus juice. At the content of 20% (v/v), the highest astaxanthin production reached 22.63 mg L(-1), which was two-fold more than that observed in yeast malt medium. Addition of 8% (v/v) n-hexadecane to the citrus medium was found to be optimal, increasing the astaxanthin yield by 21.7%.

  4. Agrobacterium-mediated transformation of Citrus sinensis and Citrus limonia epicotyl segments

    Directory of Open Access Journals (Sweden)

    Almeida Weliton Antonio Bastos de

    2003-01-01

    Full Text Available Genetic transformation allows the release of improved cultivars with desirable characteristics in a shorter period of time and therefore may be useful in citrus breeding programs. The objective of this research was to establish a protocol for genetic transformation of Valencia and Natal sweet oranges (Citrus sinensis L. Osbeck and Rangpur lime (Citrus limonia L. Osbeck. Epicotyl segments of germinated in vitro plantlets (three weeks in darkness and two weeks in a 16-h photoperiod were used as explants. These were co-cultivated with Agrobacterium tumefaciens strain EHA-105 and different experiments were done to evaluate the transformation efficiency: explants were co-cultivated with Agrobacterium for one, three or five days; explants were incubated with Agrobacterium suspension for 5, 10, 20 or 40 minutes; co-cultivation medium was supplemented with acetosyringone at 0, 100 or 200 mmol L-1; Explants ends had a longitudinal terminal incision (2-3 mm; co-cultivation temperatures of 19, 23 or 27degreesC were imposed. The experimental design was completely randomized in all experiments with five replications, each consisted of a Petri dish (100 x 15 mm with 30 explants and resulted in a total of 150 explants per treatment. Longitudinal terminal incision in the explant ends did not improve shoot regeneration. However, transgenic plants of all three cultivars were confirmed from explants that had been subjected to inoculation time of 20 minutes, co-culture of three days at 23-27degreesC, in the absence of acetosyringone.

  5. 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.

  6. Citrus pectin: structure and application in acid dairy drinks

    OpenAIRE

    Tanhatan Naseri, Abrisham; Thibault, Jean-François

    2008-01-01

    Pectin, a plant cell wall polysaccharide, is mainly used in food industries for its gelling and stabilizing properties. In industrial applications, pectin is usually widely extracted from citrus peels, and in some intances, apple pomace is also used. Lime and lemon are the preferred citrus species used in the extraction of pectin, while orange and grapefruit are used less often. In the food industry, pectin is widely employed in the production of jams and jellies, confectionary products a...

  7. Citrus bergamia essential oil: from basic research to clinical application

    OpenAIRE

    Michele eNavarra; Carmen eMannucci; Marisa eDelbò; Gioacchino eCalapai

    2015-01-01

    Citrus bergamia Risso et Poiteau, also known as Bergamot, is a plant belonging to the Rutaceae family, defined as a hybrid of bitter orange and lemon. It is an endemic plant of the Calabria region (Italy). Bergamot fruit is primarily used for the extraction of its essential oil (bergamot essential oil: BEO), employed in perfume, cosmetics, food and confections.The aim of this review was to collect recent data from the literature on Citrus bergamia essential oil and, through a critical analysi...

  8. Citrus growers vary in their adoption of biological control

    OpenAIRE

    Grogan, Kelly A.; Goodhue, Rachael E.

    2012-01-01

    In a spring 2010 survey, we investigated the characteristics that influenced whether California growers controlled major citrus pests with beneficial insects. We also performed statistical analysis of growers' reliance on Aphytus melinus, a predatory wasp, to control California red scale. The survey results suggest that growers with greater citrus acreage and more education are more likely to use biological control. Marketing outlets, ethnicity and primary information sources also influenced ...

  9. 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.

  10. In vitro organogenesis in some citrus species

    Directory of Open Access Journals (Sweden)

    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.

  11. An RNA-Seq-based reference transcriptome for Citrus.

    Science.gov (United States)

    Terol, Javier; Tadeo, Francisco; Ventimilla, Daniel; Talon, Manuel

    2016-03-01

    Previous RNA-Seq studies in citrus have been focused on physiological processes relevant to fruit quality and productivity of the major species, especially sweet orange. Less attention has been paid to vegetative or reproductive tissues, while most Citrus species have never been analysed. In this work, we characterized the transcriptome of vegetative and reproductive tissues from 12 Citrus species from all main phylogenetic groups. Our aims were to acquire a complete view of the citrus transcriptome landscape, to improve previous functional annotations and to obtain genetic markers associated with genes of agronomic interest. 28 samples were used for RNA-Seq analysis, obtained from 12 Citrus species: C. medica, C. aurantifolia, C. limon, C. bergamia, C. clementina, C. deliciosa, C. reshni, C. maxima, C. paradisi, C. aurantium, C. sinensis and Poncirus trifoliata. Four different organs were analysed: root, phloem, leaf and flower. A total of 3421 million Illumina reads were produced and mapped against the reference C. clementina genome sequence. Transcript discovery pipeline revealed 3326 new genes, the number of genes with alternative splicing was increased to 19,739, and a total of 73,797 transcripts were identified. Differential expression studies between the four tissues showed that gene expression is overall related to the physiological function of the specific organs above any other variable. Variants discovery analysis revealed the presence of indels and SNPs in genes associated with fruit quality and productivity. Pivotal pathways in citrus such as those of flavonoids, flavonols, ethylene and auxin were also analysed in detail.

  12. Physicochemical Characteristics of Citrus Seed Oils from Kerman, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reazai

    2014-01-01

    Full Text Available Recently, there has been a great deal of attention on usage, byproducts, and wastes of the food industry. There have been many studies on the properties of citrus seeds and extracted oil from citrus grown in Kerman, Iran. The rate of oil content of citrus seeds varies between 33.4% and 41.9%. Linoleic acid (33.2% to 36.3% is the key fatty acid found in citrus seeds oil and oleic (24.8% to 29.3% and palmitic acids (23.5% to 29.4% are the next main fatty acids, respectively. There are also other acids found at trivial rates such as stearic, palmitoleic, and linolenic. With variation between 0.54 meg/kg and 0.77 mgq/kg in peroxide values of citrus seed oils, acidity value of the oil varies between 0.44% and 0.72%. The results of the study showed that citrus seeds under study (orange and sour lemon grown in Kerman province and the extracted oil have the potential of being used as the source of edible oil.

  13. Influence of plant-parasitic nematodes on longleaf pine seedlings.

    Science.gov (United States)

    Ruehle, J L

    1973-01-01

    Seedlings of longleaf pine (Pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. Belonolaimus longicaudatus and Helicotylenchus dihystera had no effect on seedling growth. High inoculum densities of Hoplolaimus galeatus and Tylenchorhynchus claytoni caused a significant reduction of fresh weight of seedling roots. Root and top weights of seedlings grown in soil infested with Meloidodera floridensis or Pratylenchus brachyurus were significantly less than those of seedlings in noninfested soil. Root growth of seedlings was stimulated by the higher inoculum density of Scutellonema brachyurum.

  14. Identification and characterization of volatile components of the Japanese sour citrus fruit Citrus nagato-yuzukichi Tanaka.

    Science.gov (United States)

    Akakabe, Yoshihiko; Sakamoto, Mei; Ikeda, Yukinori; Tanaka, Mamoru

    2008-07-01

    A total of 39 aroma compounds were detected in the essential oil of Citrus nagato-yuzukichi Tanaka (nagato-yuzukichi) by gas chromatography-mass spectrometry (GC-MS). The essential oil was characterized by a high percentage of monoterpene hydrocarbons (12 components, 90.52%). The composition pattern of essential oil in C. nagato-yuzukichi was fairly similar to that of Citrus sudachi Hort. ex Shirai (Sudachi). Principal component analysis (PCA) of data obtained with an electronic nose indicated a variation of each oil along PC1. The oils of Citrus junos Tanaka (Yuzu) and Citrus sphaerocarpa Tanaka (Kabosu) showed a clear upward displacement as compared with those of C. nagato-yuzukichi and C. sudachi. However, in PC2, the oils of C. nagato-yuzukichi and C. sudachi showed a displacement in a negative direction and a positive one respectively.

  15. First occurrence of Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) preying on defoliating caterpillars of oil palm in the state of Para, Brazil; Primeira ocorrencia de Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) predando lagartas desfolhadoras do dendezeiro no estado do Para, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Rafael C.; Lemos, Walkymario P.; Muller, Antonio A. [EMBRAPA Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia], e-mail: rafaufra@yahoo.com.br, e-mail: wplemos@cpatu.embrapa.br; Muller, Antonio A. [Embrapa Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia; Bernardino, Aline S.; Buecke, Joel [Grupo Agropalma S/A., Tailandia, PA (Brazil)

    2010-01-15

    The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hubner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Para, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil. (author)

  16. Pharmacognostical evaluation of Citrus jambhiri Lush. fruit

    Directory of Open Access Journals (Sweden)

    Swapnil Y Chaudhari

    2014-01-01

    Full Text Available Background: Citrus jambhiri Lush., commonly known as Jambīra Nimbū in Sanskrit is medium to large indigenous tree with spreading habit, less spiny than lemon and belonging to the family Rutaceae. In Ayurveda, it is used in many pharmaceutical procedures of purification (Śodhana, calcination (Māraṇa etc., Though it is an important plant, till date, no pharmacognostical reports have been available on its fruit. Materials and Methods: Study of fruit and its powder, histochemical tests and preliminary physicochemical investigations were done. Results and Conclusion: Results showed prismatic crystals of calcium oxalate, aerenchyma cells, oil globules, pitted vessels, scalariform vessels, juicy sac, etc., Preliminary physicochemical analysis revealed loss on drying (1.1%, ash value (1.4%, alcohol soluble extract (28.6%, and water soluble extract (53.3%. These observations can be of use in future studies.

  17. Worker exposure to ethion in Florida citrus.

    Science.gov (United States)

    Wojeck, G A; Nigg, H N; Stamper, J H; Bradway, D E

    1981-11-01

    Dermal and respiratory exposure to ethion was determined for 17 men in eight spray crews in Florida citrus spray operations. Respiratory exposure was less than 1% of the total exposure. Hands represented 42% of the total body exposure for applicators and 76% for suppliers. At one location, suppliers exhibited a larger decrease in ChE activity than applicators. This difference appeared related to the higher mean dermal ethion exposure to suppliers. Acute symptoms of organophosphorous poisoning were not observed. The total percent/hr of the probable human dermal LD50 was very low in all cases. These data indicate a relatively low potential acute hazard to workers applying ethion with air blast equipment under the conditions of this study.

  18. Isolation, characterization and modification of citrus pectins

    Directory of Open Access Journals (Sweden)

    MARIA KRATCHANOVA

    2012-01-01

    Full Text Available Orange and lemon peels were used for obtaining pectic polysaccharides. Citrus peels were previously treated with 96% ethanol, and the obtained alcohol-insoluble solids (AIS were subjected to a sequential extraction with hot distilled water and hot 0.5% HCl. Water- and acid-extracted orange (WEOP and AEOP and lemon (WELP and AELP pectins were obtained. Acid extraction gave higher yields of pectin than water extraction and lemon peels were richer in pectin. Comparative investigations were carried out with chromatographically purified commercial citrus pectin (CPCP. Chemical and physicochemical characterization of all pectins was accomplished. It was found that pectins were similar in anhydrouronic acid content (AUАC, 69-81%, but differed in their degree of methylesterification (DM, 55-81%. Generally water-extracted pectins were with higher DM. Both orange pectins were with higher DM and degree of acetylation (DA, 2%, in comparison with the corresponding lemon pectins. Water-extracted pectins were with higher degree of feruloylation (DF, 0.12-0.34%. To our knowledge this is the first report on the estimation of ester-linked ferulic acid in orange and lemon peel pectins. Pectic polysaccharides differed in molecular weight and homogeneity. WELP was with the highest molecular weight and homogeneity. The pectins contained D-galacturonic and D-glucuronic acids, L-arabinose, D-galactose, L-fucose, L-rhamnose and D-xylose. All investigated pectins showed immunostimulating activity by complement activation in the classical pathway at 1.25 and 2.5 mg/mL. Pectic polysaccharides were modified with endopolygalacturonase. Enzyme-modified CPCP and WEOP had higher anti-complementary activity than the corresponding initial pectins.

  19. Blood Sugar Lowering Effect of Coccinia grandis (L. J. Voigt: Path for a New Drug for Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    M. A. A. K. Munasinghe

    2011-01-01

    Full Text Available Background. Role of herbs in the management and control of diabetes has emerged fast over the years. We assessed the efficacy of Coccinia grandis (locally known as Ken, Kovakka leaves as a hypoglycemic agent. Methods. Double-blind phase I clinical trial was conducted at the general hospital and a private hospital in Matara in August 2009. All the participants were given a common meal for dinner, and they maintained a 10-hour fasting period. Sixty-one healthy volunteers were given a meal containing 20 g of leaves of Coccinia grandis which was mixed with a measured amount of scraped coconut and table salt for breakfast, and other 61 were given the placebo meal which also contained scraped coconut and salt. Glucose tolerance test was performed blindly for the two groups. Mixed factorial design analysis of variance and student's t-test were applied. Results. Overall blood sugar levels of the experimental group were also significantly lower than those of the control group (F(1,117 5.56, <0.05. Increase in the blood sugar levels from fasting to one hour (F(1,117 6.77, <0.05 and two hours (F(1,117 5.28, <0.05 postprandially was statistically significant for participants who were in the control group than those of in the experimental group. The mean difference of postprandial blood sugar levels (mg/dL after one hour (20.2, 95% confidence interval, 4.81 to 35.5 and two hours (11.46, 95% confidence interval; 1.03 to 21.9 was statistically significant between the two groups. Conclusions. Coccinia grandis has a blood sugar lowering effect. However further studies are needed to validate our findings.

  20. Spatial Distribution of Adult Anthonomus grandis Boheman (Coleoptera: Curculionidae) and Damage to Cotton Flower Buds Due to Feeding and Oviposition.

    Science.gov (United States)

    Grigolli, J F J; Souza, L A; Fernandes, M G; Busoli, A C

    2016-12-12

    The cotton boll weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) is the main pest in cotton crop around the world, directly affecting cotton production. In order to establish a sequential sampling plan, it is crucial to understand the spatial distribution of the pest population and the damage it causes to the crop through the different developmental stages of cotton plants. Therefore, this study aimed to investigate the spatial distribution of adults in the cultivation area and their oviposition and feeding behavior throughout the development of the cotton plants. The experiment was conducted in Maracaju, Mato Grosso do Sul, Brazil, in the 2012/2013 and 2013/2014 growing seasons, in an area of 10,000 m(2), planted with the cotton cultivar FM 993. The experimental area was divided into 100 plots of 100 m(2) (10 × 10 m) each, and five plants per plot were sampled weekly throughout the crop cycle. The number of flower buds with feeding and oviposition punctures and of adult A. grandis was recorded throughout the crop cycle in five plants per plot. After determining the aggregation indices (variance/mean ratio, Morisita's index, exponent k of the negative binomial distribution, and Green's coefficient) and adjusting the frequencies observed in the field to the distribution of frequencies (Poisson, negative binomial, and positive binomial) using the chi-squared test, it was observed that flower buds with punctures derived from feeding, oviposition, and feeding + oviposition showed an aggregated distribution in the cultivation area until 85 days after emergence and a random distribution after this stage. The adults of A. grandis presented a random distribution in the cultivation area.

  1. Sequencing of diverse mandarin, pummelo and orange genomes reveals complex history of admixture during citrus domestication.

    Science.gov (United States)

    Wu, G Albert; Prochnik, Simon; Jenkins, Jerry; Salse, Jerome; Hellsten, Uffe; Murat, Florent; Perrier, Xavier; Ruiz, Manuel; Scalabrin, Simone; Terol, Javier; Takita, Marco Aurélio; Labadie, Karine; Poulain, Julie; Couloux, Arnaud; Jabbari, Kamel; Cattonaro, Federica; Del Fabbro, Cristian; Pinosio, Sara; Zuccolo, Andrea; Chapman, Jarrod; Grimwood, Jane; Tadeo, Francisco R; Estornell, Leandro H; Muñoz-Sanz, Juan V; Ibanez, Victoria; Herrero-Ortega, Amparo; Aleza, Pablo; Pérez-Pérez, Julián; Ramón, Daniel; Brunel, Dominique; Luro, François; Chen, Chunxian; Farmerie, William G; Desany, Brian; Kodira, Chinnappa; Mohiuddin, Mohammed; Harkins, Tim; Fredrikson, Karin; Burns, Paul; Lomsadze, Alexandre; Borodovsky, Mark; Reforgiato, Giuseppe; Freitas-Astúa, Juliana; Quetier, Francis; Navarro, Luis; Roose, Mikeal; Wincker, Patrick; Schmutz, Jeremy; Morgante, Michele; Machado, Marcos Antonio; Talon, Manuel; Jaillon, Olivier; Ollitrault, Patrick; Gmitter, Frederick; Rokhsar, Daniel

    2014-07-01

    Cultivated citrus are selections from, or hybrids of, wild progenitor species whose identities and contributions to citrus domestication remain controversial. Here we sequence and compare citrus genomes--a high-quality reference haploid clementine genome and mandarin, pummelo, sweet-orange and sour-orange genomes--and show that cultivated types derive from two progenitor species. Although cultivated pummelos represent selections from one progenitor species, Citrus maxima, cultivated mandarins are introgressions of C. maxima into the ancestral mandarin species Citrus reticulata. The most widely cultivated citrus, sweet orange, is the offspring of previously admixed individuals, but sour orange is an F1 hybrid of pure C. maxima and C. reticulata parents, thus implying that wild mandarins were part of the early breeding germplasm. A Chinese wild 'mandarin' diverges substantially from C. reticulata, thus suggesting the possibility of other unrecognized wild citrus species. Understanding citrus phylogeny through genome analysis clarifies taxonomic relationships and facilitates sequence-directed genetic improvement.

  2. Antimicrobial Activity and Phytochemical Analysis of Citrus Fruit Peels -Utilization of Fruit Waste

    Directory of Open Access Journals (Sweden)

    K. Ashok kumar

    2011-06-01

    Full Text Available Antibacterial activity of five different solvent extracts(ethyl acetate, acetone, ethanol, petroleum ether and water prepared by soxhlet extractor from two citrus fruit peel (Citrus sinensis and Citrus limon were screened against five pathogenic bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli , Klebsiella pneumonia and Salmonella typhi. The highest antibacterial potentiality was exhibited by the acetone peel extract of Citrus sinensis followed by the ethyl acetate peel extract of Citrus limon. The peel extract of Citrus sinensis and Citrus limon can be considered to be as equally potent as the antibiotics, such as metacillin and penicillin. MICs were tested at concentrations ranging from 50-6.25 mg/ml as wells as their MBCs. The phytochemical analysis of the citrus peel extracts showed the presence of flavonoids, saponins, steroids, terpenoids, tannins and alkaloids

  3. Proline content and protein patterns in Eucalyptus grandis shoots submitted to high and low temperature shocks

    Directory of Open Access Journals (Sweden)

    Gustavo M. Souza

    2004-07-01

    Full Text Available Proline content and protein patterns changes in response to temperature shocks of both acclimated and non acclimated E. grandis shoots cultivated in vitro were investigated. Analysis of soluble proteins through SDS-PAGE and proline were carried out after 12h at 12ºC (cold acclimation or 33ºC (heat acclimation, and immediately after temperature shocks at 41ºC and 0ºC. Analyses were also performed 24h after the temperature shocks (recovery period. Temperature treatment at 0ºC did not change soluble protein patterns both in acclimatized and non acclimatized plants, whereas cold temperature induced high proline levels, which kept relatively high after recovery period. Three novel, probably HSPs, proteins (90.5, 75 and 39 kDa were observed in both acclimated and non acclimated plants submitted to high temperatures. Plants exposed at 41ºC were able to recover from heat shocks after 24h, whereas they did not recover completely from cold shocks. The effect of the acclimation period on the recovering (homeostasis varied depending on the parameter evaluated, and type and duration of the temperature shock.As respostas às mudanças de temperatura de plantas aclimatadas e não aclimatadas de E. grandis cultivadas in vitro foram avaliadas considerando alterações dos níveis de prolina e proteínas solúveis totais. Análises de proteínas solúveis através de SDS-PAGE e prolina foram realizadas após 12h a 12ºC (aclimatação ao frio ou a 33ºC (aclimatação ao calor, e imediatamente depois dos choques térmicos a 41ºC e 0ºC. Análises também foram realizadas após um período de 24h depois dos choques térmicos (período de recuperação. O tratamento de temperatura a 0ºC não alterou o padrão de proteínas nas plantas aclimatadas e não aclimatadas, entretanto a temperatura baixa induziu altos níveis de prolina, que se mantiveram relativamente altos após o período de recuperação. Três novas proteínas (90,5, 75 e 39 kDa, provavelmente

  4. Diversity of Endophytic Bacterial Populations and Their Interaction with Xylella fastidiosa in Citrus Plants

    OpenAIRE

    Araujo, W.L.; Marcon, J; Maccheroni, jr., W.; Elsas, van, J.D.; Vuurde, van, M.; Azevedo

    2002-01-01

    Citrus variegated chlorosis (CVC) is caused by Xylella fastidiosa, a phytopathogenic bacterium that can infect all Citrus sinensis cultivars. The endophytic bacterial communities of healthy, resistant, and CVC-affected citrus plants were studied by using cultivation as well as cultivation-independent techniques. The endophytic communities were assessed in surface-disinfected citrus branches by plating and denaturing gradient gel electrophoresis (DGGE). Dominant isolates were characterized by ...

  5. Antimicrobial Activity and Phytochemical Analysis of Citrus Fruit Peels -Utilization of Fruit Waste

    OpenAIRE

    K. Ashok Kumar; Narayani, M.; A. Subanthini; Jayakumar, M.

    2011-01-01

    Antibacterial activity of five different solvent extracts(ethyl acetate, acetone, ethanol, petroleum ether and water) prepared by soxhlet extractor from two citrus fruit peel (Citrus sinensis and Citrus limon) were screened against five pathogenic bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli , Klebsiella pneumonia and Salmonella typhi. The highest antibacterial potentiality was exhibited by the acetone peel extract of Citrus sinensis followed by the ethyl acetate peel e...

  6. STUDIES ON ANTIMICROBIAL ACTIVITY AND PHYTOCHEMICAL ANALYSIS OF CITRUS FRUIT JUICES AGAINST SELECTED ENTERIC PATHOGENS

    OpenAIRE

    Bansode.D.S.; Chavan.M.D.

    2012-01-01

    The present study was carried out to find out the antimicrobial activity and phytochemical study of citrus fruit juices viz. Lemon (Citrus limon) and Orange (Citrus ourantium) against medically important selected enteric pathogens. As microorganisms are becoming resistant to present day antibiotics, our study focuses on antimicrobial activity and phytochemical study of Citrus fruit juices against selected enteric pathogens. Biological active compounds present in the medicinal important fruit ...

  7. Nutrient concentration age dynamics of teak (Tectona grandis L.f.) plantations in Central America

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Moya, J.; Murillo, R.; Portuguez, E.; Fallas, J. L.; Rios, V.; Kottman, F.; Verjans, J. M.; Mata, R.; Alvarado, A.

    2013-05-01

    Aim of study. Appropriate knowledge regarding teak (Tectona grandis L.f.) nutrition is required for a better management of the plantations to attain high productivity and sustainability. This study aims to answer the following questions: How can it be determined if a teak tree suffers a nutrient deficiency before it shows symptoms? Are nutrient concentration decreases in older trees associated with age-related declines in forest productivity? Area of study. Costa Rica and Panama. Material and Methods. Nutrient concentration in different tree tissues (bole, bark, branches and foliage) were measured at different ages using false-time-series in 28 teak plantations Research highlights. Foliar N concentration decreases from 2.28 in year 1 to 1.76% in year 19. Foliar Mg concentration increases from 0.23 in year 1 to 0.34% in year 19. The foliar concentrations of the other nutrients are assumed to be constant with tree age: 1.33% Ca, 0.88% K, 0.16% P, 0.12% S, 130 mg kg{sup -}1 Fe, 43 mg kg{sup -}1 Mn, 11 mg kg{sup -}1 Cu, 32 mg kg{sup -}1 Zn and 20 mg kg{sup -}1 B. The nutrient concentration values showed can be taken as a reference to evaluate the nutritional status of similar teak plantations in the region. The concentrations of K, Mg and N could be associated with declines in teak plantation productivity as the plantation becomes older. Whether age-related changes in nutrient concentrations are a cause or a consequence of age-related declines in productivity is an issue for future research with the aim of achieving higher growth rates throughout the rotation period. (Author) 35 refs.

  8. Insights into Diterpene Cyclization from Structure of Bifunctional Abietadiene Synthase from Abies grandis

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ke; Gao, Yang; Hoy, Julie A.; Mann, Francis M.; Honzatko, Richard B.; Peters, Reuben J. (Iowa State)

    2013-09-24

    Abietadiene synthase from Abies grandis (AgAS) is a model system for diterpene synthase activity, catalyzing class I (ionization-initiated) and class II (protonation-initiated) cyclization reactions. Reported here is the crystal structure of AgAS at 2.3 {angstrom} resolution and molecular dynamics simulations of that structure with and without active site ligands. AgAS has three domains ({alpha}, {beta}, and {gamma}). The class I active site is within the C-terminal {alpha} domain, and the class II active site is between the N-terminal {gamma} and {beta} domains. The domain organization resembles that of monofunctional diterpene synthases and is consistent with proposed evolutionary origins of terpene synthases. Molecular dynamics simulations were carried out to determine the effect of substrate binding on enzymatic structure. Although such studies of the class I active site do lead to an enclosed substrate-Mg{sup 2+} complex similar to that observed in crystal structures of related plant enzymes, it does not enforce a single substrate conformation consistent with the known product stereochemistry. Simulations of the class II active site were more informative, with observation of a well ordered external loop migration. This 'loop-in' conformation not only limits solvent access but also greatly increases the number of conformational states accessible to the substrate while destabilizing the nonproductive substrate conformation present in the 'loop-out' conformation. Moreover, these conformational changes at the class II active site drive the substrate toward the proposed transition state. Docked substrate complexes were further assessed with regard to the effects of site-directed mutations on class I and II activities.

  9. PRODUÇÃO DE Eucalyptus grandis Hill ex Maiden EM DIFERENTES INTENSIDADES DE DESBASTE

    Directory of Open Access Journals (Sweden)

    Gerson Mainardi

    1998-12-01

    Full Text Available O efeito de diferentes intensidades de desbaste sobre a produção Eucalyptus grandis Hill ex Maiden implantado no ano de 1981, em espaçamento inicial de 3,0 x 2,0 metros, na região de Cachoeira do Sul, Rio Grande do Sul, foi estudado com delineamento de blocos ao acaso, com duas repetições e quatro tratamentos: testemunha, sem desbastes, manutenção de 40%, 50% e 60% da área basal da testemunha, constando-se diferença significativa entre os tratamentos, ao nível de 5% de probabilidade. A produção máxima (756,3 m3cc/ha foi obtida na testemunha, sem desbaste, que não diferiu estatísticamente de 639,6 m3cc/ha, obtido no tratamento com manutenção de 60% da área basal da testemunha, porém diferiu dos tratamentos com manutenção de 50% e 40% da área basal da testemunha. A redução da área basal incrementou a concentração das freqüências nas maiores classes de diâmetro, deslocando a distribuição para a direita, porém com perdas expressivas de produção total e acréscimo significativo no diâmetro. A manutenção de 60% da área basal da testemunha permitiu as menores perdas de produção, cerca de 15,4%, e um ganho de 6,4cm ou 23,9% em incremento diamétrico das árvores remanescentes quando comparado com a testemunha, sem desbaste.

  10. PRODUCTIVITY AND COSTS OF PROCESSOR WORKING IN STANDS OF Eucalyptus grandis Hill ex Maiden

    Directory of Open Access Journals (Sweden)

    Bernardo Carlos Tarnowski

    2009-09-01

    Full Text Available In the present work a time study was conducted with the objective of adjusting equations to estimate the time of activities, productivity, operational costs and the production of the processor used in a harvest operation of stands of Eucalyptus grandis in plain topography in the state of Bahia, Brazil. The operational cycle of the processor consisted of the time spent to process a tree, and was divided in to stages, which were assessed using the methotodology of single activity times. The sampling unit was the operational cycle of the machine. The statistical analysis was based on regression analysis considering the selection procedure “stepwise”. With the adjusted equations it was possible to estimate the productivity of the machine taking into account the of tree diameter. Considering an operational efficiency of 70 % under the circumstances of the study, the productivity of the processor was 25,8 m3 cc/h, the operational costs 47,90 US$/h and the production costs 1,86 US$/m3 cc. On the basis of the obtained results it can be concluded that the time of tree processing has varied directly according to the diameter increase diameter; the preparation time, contrary to the processing time, only shows a weak correlation with tree diameter; productivity of the processor is directly proportional to tree diameter, when expressed in volume and inversely proportional when expressed in tree number; the costs per cubic meter of wood processed varies inversely with of increased diameter; from the operational costs, fixed costs had the highest proportion followed by the variable costs, administrative costs and costs for manpower; the production costs of the processor decreased exponentially with increasing tree diameter.

  11. COMBINATION OF TWO NON-INDUSTRIAL METHODS ON THE PRESERVATIVE TREATMENT OF Eucalyptus grandis FENCE POSTS

    Directory of Open Access Journals (Sweden)

    Karina Soares Modes

    2011-09-01

    Full Text Available This paper evaluated the effect of the combination of two non-industrial methods to treat fence posts of Eucalyptus grandis, on the penetration and retention of water borne preservative. Thus, four fences with 2.20 m in length were treated by replacement of sap and simple diffusion alone and other four ones have combined the two techniques, with water-borne CCB 50% preservative at a concentration of 3.5%. After each treatment condition, the pieces were seasoned in the shade for 30 days. Disks were taken at 0.60 and 1.60 m from the base of the pieces which had one side sanded for analysis of the penetration of the preservative using a solution of chrome azurol S. From the same parts, test specimens were also manufactured in diametrically opposed positions with dimensions of approximately 3.0 x 2.0 x 2.5 cm (radial x tangential x longitudinal to analyze the retention of the element copper by atomic absorption spectrophotometry method and boron by visible spectrophotometry with azomethine-H, also known as colorimetry. The retention values obtained were compared with the minimum recommended by the Brazilian Association of Technical Standards – ABNT for water borne preservatives which is 6.5 kg of active ingredients per m³ of wood. The penetration achieved by the combined method was considered sufficient for non-industrial treatment, while the retention values were higher than the retention of at least 6.5 kg of active ingredients / m³ of treated wood in all positions and portions evaluated.

  12. Insights into Diterpene Cyclization from Structure of Bifunctional Abietadiene Synthase from Abies grandis*

    Science.gov (United States)

    Zhou, Ke; Gao, Yang; Hoy, Julie A.; Mann, Francis M.; Honzatko, Richard B.; Peters, Reuben J.

    2012-01-01

    Abietadiene synthase from Abies grandis (AgAS) is a model system for diterpene synthase activity, catalyzing class I (ionization-initiated) and class II (protonation-initiated) cyclization reactions. Reported here is the crystal structure of AgAS at 2.3 Å resolution and molecular dynamics simulations of that structure with and without active site ligands. AgAS has three domains (α, β, and γ). The class I active site is within the C-terminal α domain, and the class II active site is between the N-terminal γ and β domains. The domain organization resembles that of monofunctional diterpene synthases and is consistent with proposed evolutionary origins of terpene synthases. Molecular dynamics simulations were carried out to determine the effect of substrate binding on enzymatic structure. Although such studies of the class I active site do lead to an enclosed substrate-Mg2+ complex similar to that observed in crystal structures of related plant enzymes, it does not enforce a single substrate conformation consistent with the known product stereochemistry. Simulations of the class II active site were more informative, with observation of a well ordered external loop migration. This “loop-in” conformation not only limits solvent access but also greatly increases the number of conformational states accessible to the substrate while destabilizing the nonproductive substrate conformation present in the “loop-out” conformation. Moreover, these conformational changes at the class II active site drive the substrate toward the proposed transition state. Docked substrate complexes were further assessed with regard to the effects of site-directed mutations on class I and II activities. PMID:22219188

  13. Allelopathic Sensitivity of Five Economic Species to Aqueous Leaf Extract of Eucalyptus urophylla × E.grandis with Different Ages%5种经济植物对幼龄尾巨桉叶片提取液的化感敏感性

    Institute of Scientific and Technical Information of China (English)

    王小雪; 刘芸; 邵呈龙; 唐小荐; 黄小辉; 吴艳冰; 唐吉芳; 何炳辉

    2011-01-01

    近几年,随着重庆"森林工程"全面启动,重庆西部主要区县充分利用当地有利自然条件,大规模发展速生桉树人工用材林.种植桉树需5年以上才能产生经济效益,因此,开展幼龄林林下种植成为以短养长、提高桉农收益的有效途径.但很多研究发现:桉树不仅具有较强的水、肥竞争力,而且作为一种外来树种,化感作用为其在新生境的生长和繁殖提供了"Novel weapon"(Bais et al.,2003;Hierro et al.,2003;吴锦容等,2005).%In order to guide scientifically planting on forest floor in eucalyptus plantations, screen suitable plants, and understand allelopathic effects of eucalyptus trees with different young ages (1 a, 2 a and 3 a) on the understory species and growth germination rate and seedling growth of five species widely planted in the local region were measured after treatments with different concentration of aqueous leaf extract of Eucalyptus urophylla × E. Grandis treatments with different concentration. The results showed that the leaf extract reduced seed germination rate and inhibited seedling growth of all five species, and had a stronger inhibiting effect on radical than hypocotyl growth. The species tested in this study had different sensitivity to the leaf extract. The inhibition rate of Lolium perenne, Sorghum sudanense, Phaseolus aureus, Phaseolus vulgaris and Glycine max was 56. 85% , 54. 58% , 33. 48% , 20. 81% , 16. 01% , respectively, among which Giycine max and Phaseolus vulgaris were the most insensitive to the leaf extract. The allelopathy of the leaf extract was concentration dependent, increasing with increase of the concentration, and low concentration (0.01 g · mL-1 ) had no significant influence on the species. Furthermore, the allelopathy aqueous leaf extract of E. Urophylla × E. Grandis to the five species had no significant difference with increase of their ages.

  14. Influence of 6-Benzyladenine and gelling agent on the reduction of hyperhydricity in Tectona grandis L.

    Directory of Open Access Journals (Sweden)

    Elisa Quiala

    2014-06-01

    Full Text Available Running title: Controlling hyperhydricity in teakInfluencia de la 6-Bencilaminopurina y el agente gelificante en la reducción de la hiperhidricidad en Tectona grandis L. Abstract:  The influence of different factors on shoot proliferation and the occurrence of hyperhydricity in teak (Tectona grandis L. have been studied. Four concentrations of BA (2.22, 4.44, 6.66 and 8.88 µM and a control treatment with 0 BA were examined. Aiming at reducing the costs during commercial propagation by using gelrite in stead of agar, the use of both gelling agent in the proliferation and hyperhydricity was tested. In order to evaluate if hyperhydricity can be reduced by increasing the gelrite concentration in the culture medium, three concentrations (2.0, 2.5 and 3.0 g l-1 were tested in combination with 4.44 µM BA.  The proliferation and occurrence of hyperhydricity during 21 successive subcultures were evaluated. The highest proliferation was achieved in the treatments with 6.66 or 8.88 µM BA. They yielded 5.22 and 5.56 shoots/explant, respectively. But also, the highest percent of hyperhydric shoots was achieved in this treatment. Gelrite resulted in a higher proliferation, but also an almost two times higher hyperhydricity as compared to agar-solidified media. Satisfactory reduction in hyperhydricity (18% was achieved with 3.0 g l-1 gelrite. However, the successive subcultures onto proliferation in this treatment favored hyperhydricity compromising shoot quality and its competence to proliferate. In vitro teak plants were ex vitro rooted and then transferred to greenhouse conditions for acclimatization; ten weeks after transfer they were ready for field plantation.Key words: cytokinin; forestry; micropropagation; morpho-physiological disorder; teakAbbreviations: BA- 6-Benzyladenine, MS- Murashige and Skoog basal medium, IBA- Indole-3-butyric acid, ANA-Naphtalene acetic acidResumen: Se estudió la influencia de diferentes factores en la proliferaci

  15. The fungi causin damping-off of carrot seedlings

    Directory of Open Access Journals (Sweden)

    Bogdan Nowicki

    2013-12-01

    Full Text Available When 136 samples of dying carrot seedlings from several fields were analyzed Alternaria rudicina proved to be the most common seedling pathogen (41%, followed by some Fusarium species (27%, mostly F. avenaceum.The less common seedling pathogens were Pythium spp. (13%, Phoma spp.(2,5% and Botrytis cinerea (1,4%. Some other fungi (Bipolaris sorokiniana, Sclerotinia sclerotiorum, Stemphylium botryosym and Ulocladium consortiale were found in less than 1% of seedlings examined.

  16. Diversity of endophytic bacterial populations and their interaction with Xylella fastidiosa in citrus plants

    NARCIS (Netherlands)

    Araujo, W.L.; Marcon, J.; Maccheroni, jr. W.; Elsas, van J.D.; Vuurde, van J.W.L.; Azevedo, de J.L.

    2002-01-01

    Citrus variegated chlorosis (CVC) is caused by Xylella fastidiosa, a phytopathogenic bacterium that can infect all Citrus sinensis cultivars. The endophytic bacterial communities of healthy, resistant, and CVC-affected citrus plants were studied by using cultivation as well as cultivation-independen

  17. 78 FR 58992 - Notice of Request for Extension of Approval of an Information Collection; Citrus Canker...

    Science.gov (United States)

    2013-09-25

    ... States. Citrus canker is a plant disease that affects plant and plant parts, including fresh fruit of... Collection; Citrus Canker; Interstate Movement of Regulated Nursery Stock and Fruit From Quarantined Areas... nursery stock and fruit from quarantined areas to prevent the spread of citrus canker. DATES: We...

  18. Sequencing of diverse mandarin, pummelo and orange genomes reveals complex history of admixture during citrus domestication

    Science.gov (United States)

    Cultivated citrus are selections from, or hybrids of, wild progenitor species whose identities and contributions to citrus domestication remain controversial. Here we sequence and compare citrus genomes—a high-quality reference haploid clementine genome and mandarin, pummelo, sweet-orange and sour-o...

  19. 7 CFR 457.107 - Florida citrus fruit crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... documents for each fruit type and age of trees, within a citrus fruit crop, times the coverage level percent... temperatures. Harvest. The severance of mature citrus fruit from the tree by pulling, picking, shaking, or any... the fruit type; (2) Produced by citrus trees that have not reached the fifth growing season...

  20. 7 CFR 905.149 - Procedure for permitting growers to ship tree run citrus fruit.

    Science.gov (United States)

    2010-01-01

    ... Fruit § 905.149 Procedure for permitting growers to ship tree run citrus fruit. (a) Tree run citrus fruit. Tree run citrus fruit as referenced in this section is defined in the Florida Department of... grower shall apply to ship tree run fruit using a Grower Tree Run Certificate Application, furnished...

  1. Protocol for introducing new and licensed citrus varieties into California. A Florida case study.

    Science.gov (United States)

    In the light of the current Huanglongbing (HLB) threat to the California (CA) citrus industry, and preliminary data indicating that some citrus varieties in Florida (FL) may possess some degree of tolerance to HLB, the California citrus growers indicated a strong interest in proactively introducing ...

  2. Factors affecting transmission rates of 'Candidatus Liberibacter asiaticus' by Asian citrus psyllid

    Science.gov (United States)

    The Asian citrus psyllid (ACP), Diaphorina citri, is an important pest because it transmits a bacterium ‘Candidatus Liberibacter asiaticus’ (CLas) responsible for a serious disease of citrus known as Asiatic huanglongbing (citrus greening disease). USDA-ARS researchers recently established a program...

  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. 7 CFR 301.75-17 - Funds for the replacement of certified citrus nursery stock.

    Science.gov (United States)

    2010-01-01

    ...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine and Regulations § 301.75-17 Funds for the replacement of certified citrus... 7 Agriculture 5 2010-01-01 2010-01-01 false Funds for the replacement of certified citrus...

  5. First Report of Dodder Transmission of Huanglongbing from Naturally Infected Murraya paniculata to Citrus

    Science.gov (United States)

    Huanglongbing (HLB) or “greening” disease of citrus is caused by phloem-limited, uncultured bacteria in the genus “Candidatus Liberibacter”. HLB is one of the most destructive diseases of citrus worldwide and is considered so dangerous to a U.S. citrus production that the USDA has listed “Ca. Liberi...

  6. Seed mucilage improves seedling emergence of a sand desert shrub.

    Directory of Open Access Journals (Sweden)

    Xuejun Yang

    Full Text Available The success of seedling establishment of desert plants is determined by seedling emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in seedling emergence in arid sandy environments. We hypothesized that seed mucilage enhances seedling emergence in a low precipitation regime and under conditions of sand burial. In a greenhouse experiment, two types of Artemisia sphaerocephala achenes (intact and demucilaged were exposed to different combinations of burial depth (0, 5, 10, 20, 40 and 60 mm and irrigation regimes (low, medium and high, which simulated the precipitation amount and frequency in May, June and July in the natural habitat, respectively. Seedling emergence increased with increasing irrigation. It was highest at 5 mm sand burial depth and ceased at burial depths greater than 20 mm in all irrigation regimes. Mucilage significantly enhanced seedling emergence at 0, 5 and 10 mm burial depths in low irrigation, at 0 and 5 mm burial depths in medium irrigation and at 0 and 10 mm burial depths in high irrigation. Seed mucilage also reduced seedling mortality at the shallow sand burial depths. Moreover, mucilage significantly affected seedling emergence time and quiescence and dormancy percentages. Our findings suggest that seed mucilage plays an ecologically important role in successful seedling establishment of A. sphaerocephala by improving seedling emergence and reducing seedling mortality in stressful habitats of the sandy desert environment.

  7. Containers of Attalea funifera fibers to produce eucalyptus seedlings

    Directory of Open Access Journals (Sweden)

    Andrea Vita Reis Mendonça

    2016-09-01

    Full Text Available The aim of this study was to assess the technical feasibility of using biodegradable containers made of fiber waste of Attalea funifera Martius to produce seedling of Eucalyptus camaldulensis Dehnh. The work was carried out in three stages: manufacture of piassava fiber containers, seedling production and field simulation. The experiment of seedling production was in completely randomized design, with two treatments (polyethylene tube and biodegradable container and 10 repetitions, with 64 seedlings per repetition. After 93 days, seedlings were evaluated based on quality variables. The simuation of initial growth of seedlings in the field consisted in planting seedlings in containers of 11L, in completely randomized design, with three treatments: seedlings produced in polyethylene tubes; seedlings produced in biodegradable containers, without removal of the container during planting; and seedlings produced in biodegradable containers, with removal of the container at planting, with ten repetitions, with one seedling by repetition. The biodegradable container withstood the production cycle and resulted in seedlings within acceptable standards quality. The use of biodegradable container, made of palm fibers, waived the removal of this vessel in the final planting.

  8. [Influence of seedling assortment on Panax notoginseng growth and yield].

    Science.gov (United States)

    Cui, X; Wang, C; Chen, Z

    1998-02-01

    Making Panax notoginseng seedling assortment according to seedling size before transplanting, the result shows that the influence is better, the yield of root tuber and fruit is higher. Culturing good seedling is the fundamental measure to increase yield of P. notoginseng.

  9. 75 FR 34419 - Notice of Revision and Request for Extension of Approval of an Information Collection; Citrus...

    Science.gov (United States)

    2010-06-17

    ... canker is a plant disease that affects plant and plant parts, including fresh fruit of citrus and citrus... Information Collection; Citrus Canker; Interstate Movement of Regulated Nursery Stock and Fruit from... nursery stock and fruit from quarantined areas to prevent the spread of citrus canker and to request...

  10. Preliminary evaluation on citrus demostrative plantation of health management in Fujian province%对福建省柑桔健康栽培示范园的初步评估

    Institute of Scientific and Technical Information of China (English)

    柯冲

    2001-01-01

    In 1980's, citrus demonstrative plantations of health management(called virus-free mother tree plantations ) were established in five counties in Fujian province. From the point of view of health management, the following requirements were carried out strictly: new citrus plantation was settled in isolated area far from the diseased one; the free-virus nursery seedling was used for planting material; Huanglongbing, virus diseases and their vectors were examined periodically by monitoring technique; elimination of diseased plants and prevention of insect vectors were carried out in time and management of soil, fertilizer and water was kept in good manner. The comparison of citrus demonstrative plantation of health management with control plantation in general management show that the citrus plants in former plantation grow strong and their shoots push in time, the quality of citrus fruit was superfine and quantity was great, and the economic effect of the production has prolonged for more than 5 years. The observation and survey made through out the years of 1982-1999 show that the occurrence of citrus Huanglongbing and virus diseases were completely dependent to the invasion of their insect vectors to citrus demonstrative plantations.%80年代,福建省在5个地区建立柑桔示范园(曾称为无病母本园)。按照健康栽培的观点严格实施,在隔离的地区建园,种植无病毒的苗木,对黄龙病、病毒病及其虫媒定期检测,及时铲除病株和防治虫媒,加强土壤、肥、水的管理措施。这样的柑桔健康栽培示范园,与对照柑桔园相比,前者的植株生长强壮而抽梢整齐,结果优质而高产,经济效益延长5a以上。在1982~1999年间,对示范园的观察与调研中发现,黄龙病和病毒病的发生,完全取决于能否阻止其虫媒的侵入。

  11. 菌肥对香榧等控根容器苗生长的影响%Effect of Microbial Fertilizers on Growth of Root-pruning Container Seedlings

    Institute of Scientific and Technical Information of China (English)

    翁永发; 康志雄; 陈友吾; 许利群; 程诗明; 张乃华; 方建华

    2011-01-01

    在香榧、山核桃、杨梅等控根容器苗培育过程中,选用固氮菌、解磷菌及其混合菌进行菌肥试验.结果表明:施菌肥3a后,香榧容器苗解磷菌、混合菌处理苗高生长量比对照分别增加18.26%和18.06%,差异显著(P<0.05);山核桃容器苗固氮菌、混合菌处理高生长量比对照分别增加46.25%和47.23%,差异显著(P<0.05);杨梅容器苗混合菌处理苗高生长量与对照相比差异显著(P<0.05),明显优于它们单独使用效果;此外,不同菌肥对香榧等3种苗木地径生长也有一定的促进作用.由于不同的菌肥对各树种的苗木生长促进效果有明显差异,在苗木培育过程中,应根据不同的苗木合理选用菌肥.%Experiments were conducted on application of microbial fertilizers like nitrogen fixing bacteria, phosphate-dissolving bacteria and mixed bacteria on root-pruning container seedling cultivation of Torreya grandis cv. Merrillii, Carya cathayensis, Myrica rubra. The result showed that after 3 years test, height growth of container T. grandis cv. Meirrillii seedlings treated by phosphate-dissolving bacteria and mixed one increased 18.26% and 18.06% than that of the control, with great difference(P<0.05). Height growth of container C. cathayensis seedlings treated by nitrogen fixing bacteria and mixed one increased 46.25% and 47.23% than that of the control, with great difference(P<0.05). Height growth of container Myrica rubra seedlings treated by mixed bacteria had significant different with that of the control and was better than that treated by the other two fertilizers.

  12. MICOBIOTA ASSOCIADA À MADEIRA SERRADA DE Eucalyptus grandis HILL EX MAIDEN DURANTE A SECAGEM AO AR LIVRE

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Trugilho

    2006-02-01

    Full Text Available O objetivo principal deste trabalho foi o de acompanhar a secagem ao ar livre da madeira serrada de Eucalyptus grandis conduzida na região de Lavras, MG e identificar a micobiota associada à madeira em diversas fases da secagem. As tábuas foram cortadas de oito toras de 3,0 m de comprimento, oriundas de três árvores, com 27 anos de idade, plantadas em área experimental da UFLA. Dos resultados, pôde-se concluir que a secagem da madeira de Eucalyptus grandis ao ar livre, iniciada em janeiro, consumiu 158 dias até atingir umidade próxima a 12,5%. A curva de secagem foi representada por uma equação logarítmica com coeficiente de determinação (R2 igual a 98,3%. Os fungos causadores de bolores superficiais e de manchas tiveram maior ocorrência no início da secagem. As mais altas freqüências de fungos, verificadas no início da secagem, foram observadas para Penicillium spp. e Pestalotiopsis sp. O fungo Lentinus lepideus ocorreu com maior freqüência no final da secagem.

  13. Contenido de los nutrientes básicos en Catolaccus grandis Burks criados sobre larvas del picudo del algodon

    Directory of Open Access Journals (Sweden)

    ARAUJO LÚCIA HELENA AVELINO

    2000-01-01

    Full Text Available El objetivo del trabajo fue determinar los niveles de carbohidratos, proteínas solubles y aminoácidos libres de larvas, pupas hembras y adultos hembras de Catolaccus grandis (Burks (Hymenoptera: Pteromalidae criados sobre larvas del picudo del algodón envenenadas por hembras del parasitoide y por larvas de primer instar del parasitoide. Esto estudio fue conducido en la Unidade de Investigación de Control Biologico de Plagas del Departamento de Agricultura de los Estados Unidos de la América, en Weslaco, Texas. Las 20 muestras de cada uno de los tres estados de desarrollo: tercer instar larval, pupas hembra y adultos hembra del parasitoide C. grandis, fueron separadas y pesadas individualmente y se cuantió el contenido de carbohidratos totales, proteínas solubles totales y aminoácidos libres criados en diferentes sustratos. Los resultados obtenidos confirman la existencia de patrones metabólicos significativamente distintos de estos nutrientes básicos.

  14. A four-domain Kunitz-type proteinase inhibitor from Solen grandis is implicated in immune response.

    Science.gov (United States)

    Wei, Xiumei; Yang, Jialong; Yang, Jianmin; Liu, Xiangquan; Liu, Meijun; Yang, Dinglong; Xu, Jie; Hu, Xiaoke

    2012-12-01

    Serine proteinase inhibitor (SPI) serves as a negative regulator in immune signal pathway by restraining the activities of serine proteinase (SP) and plays an essential role in the innate immunity. In the present study, a Kunitz-type SPI was identified from the mollusk razor clam Solen grandis (designated as SgKunitz). The full-length cDNA of SgKunitz was of 1284 bp, containing an open reading frame (ORF) of 768 bp. The ORF encoded four Kunitz domains, and their amino acids were well conserved when compared with those in other Kunitz-type SPIs, especially the six cysteines involved in forming of three disulfide bridges in each domain. In addition, the tertiary structure of all the four domains adopted a typical model of Kunitz-type SPI family, indicating SgKunitz was a new member of Kunitz-type SPI superfamily. The mRNA transcripts of SgKunitz were detected in all tested tissues of razor clam, including muscle, mantle, gonad, gill, hepatopancreas and hemocytes, and with the highest expression level in gill. When the razor clams were stimulated by LPS, PGN or β-1, 3-glucan, the expression level of SgKunitz mRNA in hemocytes was significantly up-regulated (P inhibitor of SP involving in the immune response of S. grandis, and provided helpful evidences to understand the regulation mechanism of immune signal pathway in mollusk.

  15. Genome scans for divergent selection in natural populations of the widespread hardwood species Eucalyptus grandis (Myrtaceae) using microsatellites

    Science.gov (United States)

    Song, Zhijiao; Zhang, Miaomiao; Li, Fagen; Weng, Qijie; Zhou, Chanpin; Li, Mei; Li, Jie; Huang, Huanhua; Mo, Xiaoyong; Gan, Siming

    2016-01-01

    Identification of loci or genes under natural selection is important for both understanding the genetic basis of local adaptation and practical applications, and genome scans provide a powerful means for such identification purposes. In this study, genome-wide simple sequence repeats markers (SSRs) were used to scan for molecular footprints of divergent selection in Eucalyptus grandis, a hardwood species occurring widely in costal areas from 32° S to 16° S in Australia. High population diversity levels and weak population structure were detected with putatively neutral genomic SSRs. Using three FST outlier detection methods, a total of 58 outlying SSRs were collectively identified as loci under divergent selection against three non-correlated climatic variables, namely, mean annual temperature, isothermality and annual precipitation. Using a spatial analysis method, nine significant associations were revealed between FST outlier allele frequencies and climatic variables, involving seven alleles from five SSR loci. Of the five significant SSRs, two (EUCeSSR1044 and Embra394) contained alleles of putative genes with known functional importance for response to climatic factors. Our study presents critical information on the population diversity and structure of the important woody species E. grandis and provides insight into the adaptive responses of perennial trees to climatic variations. PMID:27748400

  16. α-Amylase and α-Glucosidase Inhibitory Activities of Phenolic Extracts from Eucalyptus grandis × E. urophylla Bark

    Directory of Open Access Journals (Sweden)

    Ping Jiang

    2017-01-01

    Full Text Available This study evaluated the inhibitory effects of different extracts and fractions from Eucalyptus. grandis × urophylla bark (EB against α-glucosidase and α-amylase enzyme activities. The ethyl acetate extract (EB-E showed the highest activity among others. Seven fractions were derived from EB-E; among them EB-E-7 showed the highest significant inhibition of both enzymes, with IC50 of 1.40±0.18 and 1.72±0.12 μg/mL, respectively. EB-E and its active fraction EB-E-7 showed highest contents of total phenolics: 178.79±4.68 and 920.4±5.46 mg GAEag−1, respectively. HPLC-MS analysis of EB-E-7 revealed the presence of ellagic acid, quercetin-glucuronide, quercetin-3-α-rhamnopyranoside, and ellagic acid rhamnoside as major compounds, together with smaller concentrations of myricetin-rhamnoside, isorhamnetin-hexoside, myricetin-3-α-arabinofuranoside, and isorhamnetin. Therefore, the phenolic compounds from Eucalyptus grandis × E. urograndis bark potently inhibited α-amylase and α-glucosidase activity, having potential in prevention of hyperglycemia.

  17. The Role of Image Enhancement in Citrus Canker Disease Detection

    Directory of Open Access Journals (Sweden)

    K. Padmavathi

    2016-09-01

    Full Text Available Digital image processing is employed in numerous areas of biology to identify and analyse problems. This approach aims to use image processing techniques for citrus canker disease detection through leaf inspection. Citrus canker is a severe bacterium-based citrus plant disease. The symptoms of citrus canker disease typically occur in the leaves, branches, fruits and thorns. The leaf images show the health status of the plant and facilitate the observation and detection of the disease level at an early stage. The leaf image analysis is an essential step for the detection of numerous plant diseases. The proposed approach consists of two stages to improve the clarity and quality of leaf images. The primary stage uses Recursively Separated Weighted Histogram Equalization (RSWHE, which improves the contrast level. The second stage removes the unwanted noise using a Median filter. This proposed approach uses these methods to improve the clarity of the images and implements these methods in lemon citrus canker disease detection.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Study of the thermal degradation of citrus seeds

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Montoya, V. [Centro de Quimica, Instituto de Ciencias, Universidad Autonoma de Puebla, Apdo. Postal J-55, Puebla 72570, Pue (Mexico); Instituto Nacional del Carbon, CSIC, Apartado 73, E-33080 Oviedo (Spain); Montes-Moran, M.A. [Instituto Nacional del Carbon, CSIC, Apartado 73, E-33080 Oviedo (Spain); Elizalde-Gonzalez, M.P. [Centro de Quimica, Instituto de Ciencias, Universidad Autonoma de Puebla, Apdo. Postal J-55, Puebla 72570, Pue (Mexico)

    2009-09-15

    The citrus seeds are one of the principal residues in the juice industry and their utilization can decrease significantly the problems of their final disposal. In this work the thermal degradation of three Mexican citrus seeds: orange (Citrus sinensis), lemon (Citrus Limon) and grapefruit (Citrus paradisi) was studied in nitrogen atmosphere. The two components (embryo and husk) of the seeds were characterized separately. The results showed that the thermal effects are very similar between the three embryos and the three husks. The embryos show higher degradability, superior content of nitrogen and higher heating value than the husks. The thermal degradation of the components of the three seeds is completed at 600 C and it is considered to be a global process derived from the decomposition of their principal components (cellulose, hemicellulose and lignin). The results suggest that mixing the three entire seeds will not lead to a severe deviation from their individual thermal behavior and that the industry could apply them for carbonization purposes. (author)

  20. Review and prospect of thermotherapy for citrus huanglongbing%柑橘黄龙病热处理防治技术研究进展

    Institute of Scientific and Technical Information of China (English)

    贾志成; 郑加强; 黄雅杰; 周宏平; Ehsani Reza

    2015-01-01

    柑橘黄龙病正在中国、巴西和美国等地广泛传播,急需快速、有效的田间防治技术。热水和湿热空气处理对柑橘病苗和嫁接枝条有脱毒作用,在温室环境中对病苗木进行光照热疗,可以减少黄龙病病菌数量,促进其健康生长并有效延长产果寿命。该文针对柑橘黄龙病防治技术的研究现状,综述了基因改良育种、苗木脱毒、化学防治、物理防治和生物防治等方法,结合热疗法在微生物和昆虫杀灭中的广泛应用,分析了田间热处理防治技术研究中存在的主要问题,提出了研究柑橘黄龙病病菌热处理温度阈值和对应时间、建立田间黄龙病病情快速诊断和热处理防治效果评价体系、研究热处理对黄龙病病菌抑制和消杀机理以及不同传热介质在柑橘树体的传热过程和特性、建立黄龙病田间快速热处理系统、研究黄龙病综合防治方法等建议,可为进一步研究柑橘黄龙病田间防治技术提供参考。%The citrus Huanglongbing (HLB or greening), caused by the phloem-limited bacterium Candidatus Liberibacter spp, is a highly destructive citrus disease in the world. Nowadays, HLB is widely spread in China, USA, Brazil and other countries. Without effective control of infected citrus in the field, the citrus industry may meet a serious destruction in near future. Some promising progresses have been made in genetic improvement, seedling detoxification, chemical control, physical control and biological control. However, there is no effective field control method and equipment with high efficiency and low cost available for HLB control. It was already confirmed that, at suitable temperature and appropriate length of time, infected seedling and grafted branch could be free from HLB infection by the heat treatment with hot water and water vapor saturated hot air. In a greenhouse circumstance, the nursery citrus tree with HLB infection gets

  1. 桉树枝瘿姬小蜂危害巨园桉的研究%Study on Leptocybe invasa's Hazard to Eucalyptus grandis × E.tereticonis

    Institute of Scientific and Technical Information of China (English)

    陈江; 王缉健; 刘宇; 罗基同; 蒋金培; 吴耀军

    2010-01-01

    桉树枝瘿姬小蜂(Leptocybe invasa Fish er & La salle)在巨园桉(E.grandis×E.tereticornis)DH201-2不同生长阶段和不同生长高度均能侵入定居,并产生大量虫瘿,对巨园桉危害严重.

  2. The IDA peptide controls abscission in Arabidopsis and Citrus

    Directory of Open Access Journals (Sweden)

    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.

  3. Selection processes in a citrus hybrid population using RAPD markers

    Directory of Open Access Journals (Sweden)

    Oliveira Roberto Pedroso de

    2003-01-01

    Full Text Available The objective of this work was to evaluate the processes of selection in a citrus hybrid population using segregation analysis of RAPD markers. The segregation of 123 RAPD markers between 'Cravo' mandarin (Citrus reticulata Blanco and 'Pêra' sweet orange (C. sinensis (L. Osbeck was analysed in a F1 progeny of 94 hybrids. Genetic composition, diversity, heterozygosity, differences in chromosomal structure and the presence of deleterious recessive genes are discussed based on the segregation ratios obtained. A high percentage of markers had a skeweness of the 1:1 expected segregation ratio in the F1 population. Many markers showed a 3:1 segregation ratio in both varieties and 1:3 in 'Pêra' sweet orange, probably due to directional selection processes. The distribution analysis of the frequencies of the segregant markers in a hybrid population is a simple method which allows a better understanding of the genetics of citrus group.

  4. 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.

  5. 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.

  6. Water management in hardening Maytenus ilicifolia (Schrad. Planch. seedlings

    Directory of Open Access Journals (Sweden)

    João Alexandre Lopes Dranski

    2017-02-01

    Full Text Available This study evaluated the effects of seedling height and irrigation management on M. ilicilofia seedlings. The experiment used a completely randomized design in a 2 x 3 factorial arrangement. Seedlings of two height classes (greater than or less than 18.0 cm were subjected to three irrigation regimes (daily irrigation, irrigation every other day, and gradual reduction of irrigation. After eight weeks, the morphophysiological and performance attributes of the seedlings were quantified. Gradual reduction of irrigation promoted the highest rate of net carbon assimilation. Irrigating every other day resulted in greater secondary growth rate, biomass accumulation in the shoot and root tissues, and lower electrolyte leakage rate. After planting, these treatments maintained higher leaf relative water content (RWC. RWC in seedlings smaller than 18 cm was significantly higher until the third week after planting. Therefore, larger seedlings submitted to hardening by gradually reducing irrigation improves seedling quality.

  7. SUBSTRATOS DE ORIGEM ORGÂNICA PARA PRODUÇÃO DE MUDAS DE TECA (Tectona grandis Linn. F.

    Directory of Open Access Journals (Sweden)

    Paulo André Trazzi

    2013-01-01

    Full Text Available The utilization of renewable waste as a source of nutrients for forest seedlings production can be a solution to environmental problems, mainly related to the disposal of these materials. In this context, this study aimed to evaluate the use of renewable substrates as substrate components in the production of teak seedlings. Seedlings were grown in tubes with a volume capacity of 280 cm3, using for the composition of treatments cattle manure, poultry litter or manure quail associated with subsoil earth and a fraction of 25% of commercial forestry substrate, and the formed substrates were subjected to chemical analysis. Ninety days after transplanting the seedlings, the following morphological characteristics were analyzed: shoot height, stem diameter, dry weight of shoots, roots and total and Dickson quality index. The results indicated that the seedlings produced with substrates formulated with poultry litter had the highest growth from the traits studied, given that the treatment with 35% of this material provided the greatest gains. The use of renewable substrates may be indicated for forest seedling production, contributing for the improvement of the chemical properties of substrates formed and consequently for the plant nutrition.

  8. Produção de Eucalyptus grandis Hhill ex Maiden em diferentes intensidades de desbaste.

    Directory of Open Access Journals (Sweden)

    Paulo Renato Schneider

    2009-09-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 O efeito de diferentes intensidades de desbaste sobre a produção Eucalyptus grandis Hill ex Maiden implantado no ano de 1981, em espaçamento inicial  de 3,0 x 2,0 metros, na região de Cachoeira do Sul, Rio Grande do Sul, foi estudado com delineamento de blocos ao acaso, com duas repetições e quatro tratamentos: testemunha, sem desbastes, manutenção de 40%, 50% e 60% da área basal da testemunha, constando-se diferença significativa entre os tratamentos, ao nível de 5% de probabilidade. A produção máxima (756,3 m3cc/ha foi obtida na testemunha, sem desbaste, que não diferiu estatísticamente de 639,6 m3cc/ha, obtido no tratamento com manutenção de 60% da área basal da testemunha, porém diferiu dos tratamentos com manutenção de 50% e 40% da área basal da testemunha. A redução da área basal incrementou a concentração das freqüências nas maiores classes de diâmetro, deslocando a distribuição para a direita, porém com perdas expressivas de produção total e acréscimo significativo no diâmetro. A manutenção de 60% da área basal da testemunha permitiu as menores perdas de produção, cerca de 15,4%, e um ganho de 6,4cm ou 23,9% em  incremento  diamétrico  das  árvores  remanescentes quando comparado com a testemunha, sem desbaste.

  9. Enhanced Acquisition Rates of 'Candidatus Liberibacter asiaticus' by the Asian Citrus Psyllid (Hemiptera: Liviidae) in the Presence of Vegetative Flush Growth in Citrus.

    Science.gov (United States)

    Sétamou, Mamoudou; Alabi, Olufemi J; Kunta, Madhurababu; Jifon, John L; da Graça, John V

    2016-10-01

    The Asian citrus psyllid preferentially feeds and exclusively reproduces on young, newly emerged flush shoots of citrus. Asian citrus psyllid nymphs feed and complete their life stages on these flush shoots. Recent studies conducted under greenhouse conditions have shown that the transmission rates of 'Candidatus Liberibacter asiaticus' (CLas), the putative causal agent of huanglongbing disease of citrus, are enhanced when flush shoots are present. However, it is unclear if CLas acquisition by migrant adult Asian citrus psyllids is similarly enhanced. To address this knowledge gap, cohorts of Asian citrus psyllid adults were allowed 1-wk acquisition access period (AAP) on flushing and nonflushing shoots of qPCR-tested symptomatic (CLas+) and asymptomatic (CLas-) 10-yr-old sweet orange trees under field conditions. After the AAP, they were tested for CLas by qPCR. Progeny Asian citrus psyllid adults that emerged 4 wk post-AAP were similarly retrieved and tested. Eighty percent of flushing and 30% of nonflushing CLas+ trees produced infective Asian citrus psyllid adults, indicating that flush shoots have greater potential to be inoculum sources for CLas acquisition. Concomitantly, 21.1% and 6.0% infective adults were retrieved, respectively, from flushing and nonflushing CLas+ trees, indicating that Asian citrus psyllid adults acquire CLas more efficiently from flush shoots relative to mature shoots. In addition, 12.1% of infective Asian citrus psyllid adult progeny were obtained from 70% of flushing CLas+ trees. Significantly lower mean Ct values were also obtained from infective adults retrieved from flushing relative to nonflushing trees. The results underscore the role of flush shoots in CLas acquisition and the need to protect citrus trees from Asian citrus psyllid infestations during flush cycles.

  10. Behavioral effects of Citrus limon in rats.

    Science.gov (United States)

    Khan, Rafeeq Alam; Riaz, Azra

    2015-04-01

    Anxiety and depression are increasing worldwide, however these disorders may be managed by making healthier changes is dietary pattern, since there are evidences that diet rich in antioxidants and vitamins help reduce anxiety and depression. Hence present study was designed to evaluate the behavioral effects of Citrus limon in rats at three different doses i.e. 0.2, 0.4 and 0.6 ml/kg considered as low, moderate and high doses. Anxiolytic and antidepressant activities were specifically assessed twice during 15 days using open field test, elevated plus maze and forced swimming test. In open field test C. limon, revealed increase in distance travelled, number of central entries and number of rearing's at moderate dose, while in the elevated plus maze, number of open arm entries were found to be increased. Whereas in forced swimming test, there was decrease in duration of immobility and increase in duration of climbing. Thus results of present study suggest that C. limon at moderate dose have anxiolytic effect.

  11. In Vitro Propagation of Citrus Rootstocks

    Directory of Open Access Journals (Sweden)

    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.

  12. 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

  13. Chemical compounds effective against the citrus Huanglongbing bacterium 'Candidatus Liberibacter asiaticus' in planta.

    Science.gov (United States)

    Zhang, Muqing; Powell, Charles A; Zhou, Lijuan; He, Zhenli; Stover, Ed; Duan, Yongping

    2011-09-01

    Citrus Huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide and is threatening the survival of the Floridian citrus industry. Currently, there is no established cure for this century-old and emerging disease. As a possible control strategy for citrus HLB, therapeutic compounds were screened using a propagation test system with 'Candidatus Liberibacter asiaticus'-infected periwinkle and citrus plants. The results demonstrated that the combination of penicillin and streptomycin (PS) was effective in eliminating or suppressing the 'Ca. L. asiaticus' bacterium and provided a therapeutically effective level of control for a much longer period of time than when administering either antibiotic separately. When treated with the PS, 'Ca. L. asiaticus'-infected periwinkle cuttings achieved 70% of regeneration rates versus citrus plants. This may provide a useful tool for the management of citrus HLB and other Liberibacter-associated diseases.

  14. 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.

  15. 柑橘黄龙病的为害传播与综合防控措施%Pathogen transmission and comprehensive control measures of citrus Huanglongbing

    Institute of Scientific and Technical Information of China (English)

    林天从

    2015-01-01

    总结柑橘黄龙病的主要危害特征、传播方式和发病条件,提出严格检疫、脱毒育苗、隔离建园、病虫防治、清除病树、加强宣传等综合防治措施.%This paper summarized main damage character,transmission manner and occurrence conditions of citrus Huan-glongbing and proposed control measures,including strict quarantine,detoxifying nursery of Virus-free seedlings,deVelop-ment of pathogen-isolated orchard,control of diseases and pests and strengthening propaganda.

  16. Trophic discrimination factor of nitrogen isotopes within amino acids in the dobsonfly Protohermes grandis (Megaloptera: Corydalidae) larvae in a controlled feeding experiment.

    Science.gov (United States)

    Ishikawa, Naoto F; Hayashi, Fumio; Sasaki, Yoko; Chikaraishi, Yoshito; Ohkouchi, Naohiko

    2017-03-01

    The trophic discrimination factor (TDF) of nitrogen isotopes ((15)N/(14)N) within amino acids, between a stream-dwelling dobsonfly larva (Protohermes grandis: Megaloptera; Corydalidae) and its diet (chironomid larvae), was determined in controlled feeding experiments. Last-instar larvae of P. grandis were collected from the Yozawa-gawa River, central Japan, and reared in the laboratory. After fed to satiation for 1 month, one group of larvae was each fed one living chironomid larva per day for 4 weeks, while a second group was starved for 8 weeks. The larvae were harvested at intervals and the nitrogen isotopic composition of glutamic acid (δ(15)NGlu) and phenylalanine (δ(15)NPhe) were determined to calculate TDF. The mean TDF of satiated and starved larvae were 7.1‰ ± 0.5‰ (n = 3) and 7.3‰ ± 0.5‰ (n = 5), respectively. Thus, the TDF for P. grandis larvae in this study was similar to that reported for other arthropods (approximately 7‰) and was independent of satiation or starvation. A previous study of wild P. grandis larvae, based on the δ(15)NGlu and δ(15)NPhe values, estimated its trophic position (TP) as approximately 2.0 ± 0.1 (n = 5), a low value close to that of algivores, although they are generally characterized as carnivores (usually accepted as TP ≥ 3). The TDF for P. grandis larvae suggests that their low TPs in nature were caused by incorporation of vascular plant-derived amino acids (with a different δ(15)N profile from that of algae) and not by an unusually low TDF or by the effects of the satiation/starvation on amino acid metabolism.

  17. Physiological and Molecular Responses to Excess Boron in Citrus macrophylla W.

    Science.gov (United States)

    Martínez-Cuenca, Mary-Rus; Martínez-Alcántara, Belén; Quiñones, Ana; Ruiz, Marta; Iglesias, Domingo J; Primo-Millo, Eduardo; Forner-Giner, M Ángeles

    2015-01-01

    This work provides insight into several mechanisms involved in boron (B) regulation pathway in response to high B conditions in Citrus. The study was carried out in Citrus macrophylla W. (Cm) seedlings cultured "in vitro" in media with 50 or 400 μM H3BO3 (control, Ct, and B-excess, +B, plants, respectively). Growth parameters, B concentration, leaf chlorophyll (Chl) concentration, the expression of the main putative genes involved in B transport and distribution, and leaf and root proline and malonaldehyde (MDA) concentrations, were assessed. Excess B led to high B concentration in +B plants (3.8- and 1.4-fold in leaves and roots, respectively) when compared with Ct ones. However, a minor effect was recorded in the plant (incipient visual symptoms, less than 27% reduction in root growth and 26% decrease in Chl b concentration). B toxicity down-regulated by half the expression level of putative B transporter genes NIP5 and PIP1. CmBOR1 gene was not repressed in +B plants and B accumulated in the shoots. High B level increased the transcripts of putative gene TIP5, involved in B transport across the tonoplast, by 3.3- and 2.4-fold in leaves and roots, respectively. The activity of V-PPiase proton pump, related with the electrochemical gradient in the vacuole, was also enhanced in +B organs. B toxicity up-regulated putative BOR4 gene (2.1- and 2.7-fold in roots and leaves, respectively), which codifies for an active efflux B transporter. Accordingly, B was located in +B plants preferently in an insoluble form on cell walls. Finally, excess B caused a significant rise in proline concentration (51% and 34% in roots and leaves, respectively), while the MDA level did not exceed 20%. In conclusion, Cm tolerance to a high B level is likely based on the synergism of several specific mechanisms against B toxicity, including: 1/ down-regulation of NIP5 and PIP1 boron transporters; 2/ activation of B efflux from cells due to the up-regulation of putative BOR4 gene; 3

  18. Postfire seedling dynamics and performance in Pinus halepensis Mill. populations

    Science.gov (United States)

    Daskalakou, Evangelia N.; Thanos, Costas A.

    2010-09-01

    Postfire dynamics of Aleppo pine seedling density, survival and growth were assessed in five burned forests of Attica, Greece (Stamata, Villia, Avlona, Kapandriti and Agios Stefanos) through the establishment of permanent experimental plots. All emerging seedlings were tagged and their survival and growth monitored at regular intervals. Seedling density dynamics show an initial, steep increase (to maximum values 2.9-4.6 seedlings m -2) followed by a gradual decrease that levels off at the second and third postfire year (1.3-3.0 seedlings m -2); similarly, postfire seedling survival more or less stabilised at 30-50%, 2-3 years after fire. On the basis of density and mortality trends as well as relevant bibliographic data, it is predicted that very dense, mature forests (10.000 trees ha -1 or more) will be reinstated within 15-20 years. During the first 5-7 postfire years, seedling/sapling annual height followed linear trends with various yearly rates, ranging mostly between 8 and 15 cm (and 27-30 cm in two exceptional, fast growing cases). Within an individual growth season, seedling height dynamics were found to follow sigmoid curves with growth increment peaks in mid-spring. The time (on a monthly basis) of seedling emergence did not affect seedling growth or survival. On the other hand, for the first time under natural conditions, it has been shown that cotyledon number per seedling, an indirect measure of both seed size and initial photosynthetic capacity, significantly affected seedling survival but not growth. Seedlings bearing a higher number of cotyledons, presumably derived from larger seeds, showed greater survival at the end of the first postfire year than seedlings with fewer cotyledons. A postfire selective pressure, favouring large seed size, is postulated to counteract with a contrasting one, which favours small seed size, expressed during fire-free conditions.

  19. Energy conservation in citrus processing. Final project report

    Energy Technology Data Exchange (ETDEWEB)

    Leo, M.A.; Lari, R.I.; Moore, N.R.; Broussard, M.R.; Gyamfi, M.

    1981-11-01

    Alternative energy conserving systems for use in citrus processing plants were synthesized and evaluated in terms of energy savings and economic return. The energy intensive operations that are carried out in citrus processing plants include conveying and extraction, concentration, peel drying, refrigeration, and pasteurization. The alternative energy conserving systems are synthesized from components and subsystems that are arranged to make use of energy cascading and thermodynamic regeneration to reduce the overall energy usage. System requirements such as air pollution rules and plant processing load cycles, a characterization of major operations, description of alternative system concepts, and the evaluation of alternative systems in terms of economic parameters and energy usage are identified.

  20. Citrus Tristeza Virus on the Island of Crete

    DEFF Research Database (Denmark)

    Shegani, M.; Tsikou, D.; Velimirovic, A.

    2012-01-01

    ) region using quantitative RT-PCR, revealed consistent differences in abundance for each of these RNAs among flowers, stems, young fruits and leaves of infected orange trees. CTV p23 RNAs accumulated at highest levels, reaching a maximum in the flowers and the lowest levels in the leaves, while POL RNAs......Over a period of two years, more than 5,000 citrus trees were tested for the presence of Citrus tristeza virus (CTV) on the island of Crete, resulting in thirty eight positives. Comparisons of the relative transcript levels of CTV p23, coat protein (CP), polymerase (POL) and an intergenic (POL/p33...

  1. Weed Biomass and Weed Species Diversity of Juvenile Citrus Trees Intercrop with some Arable Crops

    Directory of Open Access Journals (Sweden)

    Patience Mojibade OLORUNMAIYE

    2012-02-01

    Full Text Available A preliminary study was carried out to evaluate the performances of eight crops in the intercrop of citrus with arable crops at the National Horticultural Research Institute (NIHORT Ibadan, Nigeria. Eight arable crops: maize, cucumber, sweet potato, Corchorus olitorius, large green, grain amaranth, Mucuna pruriens var. utilis, and groundnut were intercropped with young citrus trees in the early planting season of 2010 with sole citrus as control. The experiment was laid out in a completely randomized block design with three replicates. Data were collected on weed flora, weed density and weed dry weight. Results showed that the relative frequencies of weeds in all the plots were less than 4% at both 6 and 9WAP. Gomphrena celosoides, Oldenlandia corymbosa and Tridax procumbens were most preponderant in appearing in all the plots. Tridax procumbens had a consistent relative frequency (2.34% in all the plots except in citrus/maize plot (0.78% at 9 WAP. Significantly lower broadleaf weed densities were obtained in citrus/sweet potato, citrus/large green, control plot and citrus/cucumber (28.67, 45.00, 50.00 and 76.33 m-2 respectively than in citrus/groundnut plot (143.00 m-2. Similarly, significantly lower grass weed densities were produced in citrus/Mucuna and citrus/sweet potato (0.33 m-2 each plots than the control plot (11.33 m-2. Whereas citrus/corchorus plot produced significantly lower broadleaf weed dry weight (37.59 g m-2 than citrus/Mucuna plot (126.47 g m-2 at 3WAP, citrus/large green plot (16.15 g m-2 and citrus/groundnut plot (123.25 g m-2 followed the same trend at 6 WAP. Sedges dry weights were less than 7 g m-2 in all the plots compared with control plot.

  2. [Pontoscolex corethrurus (Annelidae: Oligochaeta) soil quality indicator in Eucalyptus grandis (Myrtacea) sites with slash and burn management].

    Science.gov (United States)

    Uribe, Sheila; Huerta, Esperanza; Geissen, Violette; Mendoza, Manuel; Godoy, Roberto; Jarquín, Aarón

    2012-12-01

    Soil burning has been used in agricultural and forestry systems as a fundamental technique to clean the land and add some nutrients to the soil. In addition, earthworms are known to promote various soil functions since they contribute to aeration and organic matter and nutrients availability to other soil organisms. This study evaluated the effects of tropical forest crops management with presence-absence of Eucalyptus grandis on earthworm population in Huimanquillo, Tabasco, Mexico. Three sites (average area of 1-1.5ha each) with different management conditions were considered for soil and earthworm sampling (two depths and six replicates): without vegetation (SV) and recent slash-burned (38 days), forest crops of five years of production of E. grandis (Euc), and secondary vegetation of 15 years (Acah). Soil physico-chemical properties (apparent density, humidity, texture, pH, Ntot, OM, P, K, cationic capacity) were also evaluated, and earthworms were collected at the end of the rainy season (august-october 2007). We found that the sites soil is an acrisol acid, with pH 3.0-4.5 in the first 30cm depth. Organic matter content (OM) and total nitrogen (Ntot) in the recently burned sites were significantly lower (6-8% y 0.19-0.22%, respectively) than in sites with vegetation (OM=9-11%; el Ntot=0.27-0.33%). Only one species (P. corethrurus) was found in all the sampled areas, where most of the individuals were at juvenile stage (80%). The highest densities and biomass were found in Euc. treatment (166.4ind/m2 y 36.8g/m2) followed by Acah (138.7ind/m2 y 19.1g/m2 respectively), while the SV treatment showed of about an 80% reduced earthworm populations when compared to other treatments. Even though 15 years have passed over the secondary vegetation (Acah) still some perturbations were observed as the low abundance of the oligochaeta group. We concluded that the management used to culture E. grandis produces negative effects over the abundance and diversity of earthworms

  3. Production and carbon allocation in monocultures and mixed-species plantations of Eucalyptus grandis and Acacia mangium in Brazil.

    Science.gov (United States)

    Nouvellon, Yann; Laclau, Jean-Paul; Epron, Daniel; Le Maire, Guerric; Bonnefond, Jean-Marc; Gonçalves, José Leonardo M; Bouillet, Jean-Pierre

    2012-06-01

    Introducing nitrogen-fixing tree species in fast-growing eucalypt plantations has the potential to improve soil nitrogen availability compared with eucalypt monocultures. Whether or not the changes in soil nutrient status and stand structure will lead to mixtures that out-yield monocultures depends on the balance between positive interactions and the negative effects of interspecific competition, and on their effect on carbon (C) uptake and partitioning. We used a C budget approach to quantify growth, C uptake and C partitioning in monocultures of Eucalyptus grandis (W. Hill ex Maiden) and Acacia mangium (Willd.) (treatments E100 and A100, respectively), and in a mixture at the same stocking density with the two species at a proportion of 1 : 1 (treatment MS). Allometric relationships established over the whole rotation, and measurements of soil CO(2) efflux and aboveground litterfall for ages 4-6 years after planting were used to estimate aboveground net primary production (ANPP), total belowground carbon flux (TBCF) and gross primary production (GPP). We tested the hypotheses that (i) species differences for wood production between E. grandis and A. mangium monocultures were partly explained by different C partitioning strategies, and (ii) the observed lower wood production in the mixture compared with eucalypt monoculture was mostly explained by a lower partitioning aboveground. At the end of the rotation, total aboveground biomass was lowest in A100 (10.5 kg DM m(-2)), intermediate in MS (12.2 kg DM m(-2)) and highest in E100 (13.9 kg DM m(-2)). The results did not support our first hypothesis of contrasting C partitioning strategies between E. grandis and A. mangium monocultures: the 21% lower growth (ΔB(w)) in A100 compared with E100 was almost entirely explained by a 23% lower GPP, with little or no species difference in ratios such as TBCF/GPP, ANPP/TBCF, ΔB(w)/ANPP and ΔB(w)/GPP. In contrast, the 28% lower ΔB(w) in MS than in E100 was explained both by

  4. Soil attributes and wood quality for pulp production in plantations of Eucalyptus grandis clone Atributos do solo e qualidade da madeira para produção de celulose em plantações clonais de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    José Luiz Gava

    2008-01-01

    Full Text Available The soil attributes can affect the wood quality of eucalypt, which may result in considerable effect on cellulose production. This study evaluated the effect of different physical and chemical soil attributes on wood quality of Eucalyptus grandis for cellulose production. Five sites were selected at the Western Plateau of the State of São Paulo, planted with one clone of Eucalyptus grandis, with ages ranging between 6.5 and 7.0 years. Four soil types, with texture ranging from sandy to very clayey were found. At each site, three experimental plots were allocated with 100 trees each. Trees representative of each class frequency of diameter at breast height were harvested. Their biomass and wood components were characterized. The wood productivity and quality was affected by physical attributes of soil, mainly clay content, which is directly related to the amount of available water. Basic wood density did not changed at different soil types. Total lignin content decreased and holocellulose content exponentially increased as soil clay content increased (until about 350 to 400 g kg-1 of clay. The wood extractives content was not affected by soil attributes. Screened cellulose yield exponentially increased with soil clay content.Os atributos edáficos podem afetar a qualidade da madeira de eucalipto, o que pode resultar em considerável efeito sobre a produção de celulose. Este trabalho teve como objetivo avaliar o efeito de atributos físicos e químicos do solo na qualidade da madeira de Eucalyptus grandis usada para polpação celulósica. Foram selecionadas cinco áreas no planalto ocidental do Estado de São Paulo, Brasil, plantadas com um mesmo clone de Eucalyptus grandis, com idades variando entre 6,5 e 7,0 anos de idade. Quatro classes de solo, com textura arenosa a muito argilosa, foram encontradas. Em cada uma das cinco áreas, foram demarcadas, aleatoriamente, 3 parcelas com 100 plantas cada. Em cada parcela, foram colhidas

  5. Organogenesis and transient genetic transformation of the hybrid Eucalyptus grandis × Eucalyptus urophylla Organogênese e transformação genética transiente do híbrido Eucalyptus grandis × Eucalyptus urophylla

    Directory of Open Access Journals (Sweden)

    Giovana Bomfim de Alcantara

    2011-04-01

    Full Text Available The hybrid Eucalyptus grandis x Eucalyptus urophylla presents high levels of productivity and potential for use in paper, cellulose and fiber industries. The bud organogenesis from leaf explants of two clones of E. grandis × E. urophylla was studied in order to verify the effect of several factors: subculture duration on multiplication medium, type of explants, entire and half leaves: basal and apical portions, and duration of the culture on a regeneration medium. Differences in organogenic capacity of the two clones tested were observed. The explant most recommended for organogenesis is the basal section of the leaf collected from shoot clusters subcultured every 17 days. Moreover, the leaf explants must be transferred to a fresh bud induction medium every five days. This study also aimed at evaluating factors affecting the genetic transformation of leaf explants with the uidA gene, via co-cultivation with Agrobacterium tumefaciens, such as the pre-culture of the explants on a specific medium, the duration of their co-culture with the bacteria and the addition of acetosyringone to the culture media. The best conditions for the expression of the uidA gene were two days of pre-culture of the leaf tissues, three days of co-culture with the bacteria and the addition of acetosyringone in pre- and co-culture media.O híbrido Eucalyptus grandis x Eucalyptus urophylla apresenta alta produtividade e potencial para indústrias de papel, celulose e fibras. A organogênese de explantes foliares de dois clones de E. grandis × E. urophylla foi estudada para verificar fatores como tempo de repicagem das plântulas matrizes em meio de multiplicação; tipo de explantes, folhas inteiras e de meias-folhas (porções basais e apicais e dos dias que os explantes foliares permaneceram em meio de regeneração. Foram observadas diferenças na capacidade organogênica dos dois clones testados. A parte basal das folhas, coletadas de brotações repicadas a cada 17

  6. Estudo de algumas propriedades mecânicas da madeira de um híbrido clonal de Eucalyptus urophylla X Eucalyptus grandis Study of some mechanical properties of wood in a clonal hybrid of Eucalyptus urophylla X Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Fabrício Gomes Gonçalves

    2009-06-01

    Full Text Available A procura por madeiras oriundas de reflorestamentos destinadas à serraria é uma realidade já há muitos anos, principalmente aquelas das espécies do gênero Eucalyptus. Visando buscar novas informações importantes para esse mercado, este trabalho objetivou determinar algumas propriedades mecânicas da madeira de um híbrido clonal de Eucalyptus urophylla x Eucalyptus grandis de duas idades e provenientes de talhadia simples e de reforma. Os resultados indicaram que a madeira desse híbrido apresenta boas características tecnológicas, destacando-se a segunda tora (a partir de 3 m com as melhores propriedades de flexão estática (Módulo de Elasticidade - MOE e Módulo de Ruptura - MOR e Compressão Axial das fibras. As árvores de maior idade (166 meses e que sofreram dois desbastes apresentaram as melhores propriedades de flexão estática e compressão axial.The search for wood originated from reforestations destined to sawmill has been observed for many years, mainly for the Eucalyptus species. Searching for information to assist this market, the aim of this study was to determine some mechanical properties of the wood from a Eucalyptus urophylla x Eucalyptus grandis clonal hybrid, at two different ages and coming from coppice and reform. The results show that the wood of this clonal hybrid presents good technological characteristics and is the second best log (starting from 3,0 m, as to static bending properties (Module of Elasticity - MOE and Module of Rupture - MOR. The oldest trees (166 months - E2 which suffered two thinning presented the best results for the property of static bending and axial crushing (CA.

  7. Compósitos de partículas de madeira de Eucalyptus grandis, polipropileno e polietileno de alta e baixa densidades Composites of Eucalyptus grandis wood, polypropylene, and high and low-density polyethylene particles

    Directory of Open Access Journals (Sweden)

    Emerson Gomes Milagres

    2006-06-01

    Full Text Available Este trabalho teve como objetivo determinar as propriedades de painéis fabricados com mistura de partículas de madeira de Eucalyptus grandis, polietileno de alta densidade, polietileno de baixa densidade e polipropileno. Empregaram-se duas formulações adesivas (uréia-formaldeído e uréia-formaldeído contendo 0,5% de epóxi. De modo geral, as propriedades dos painéis foram afetadas pela composição das partículas. Os painéis com melhores propriedades foram fabricados com 75% de partículas de madeira e 25% de partículas de polietileno de alta densidade. A adição de epóxi ao adesivo uréico aumentou os valores do módulo de ruptura, dureza Janka, e reduziu o inchamento, em espessura, de alguns painéis. As propriedades mecânicas da maioria dos painéis, exceto o módulo de elasticidade, ultrapassaram os valores mínimos estabelecidos na norma ANSI/A1-208/93.The objective of this work was to establish the properties of particleboards fabricated with blends of Eucalyptus grandis, low-density polyethylene, high-density polyethylene and polypropylene particles. Two adhesives formulations were used (urea-formaldehyde and urea-formaldehyde plus 0,5% of epoxy adhesive. Panel properties were affected by particle composition. Panels with best properties were fabricated with 75% of wood particles and 25% of high density polypropylene. The addition of epoxy to the urea-formaldehyde adhesive improved of the values of modulus of rupture, hardness and reduced the amount of thickness swelling. Except for the modulus of elasticity, board properties meet grade M-2 ANSI/A1-208/93 requirements.

  8. 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

  9. Multiple amine oxidases in cucumber seedlings.

    Science.gov (United States)

    Percival, F W; Purves, W K

    1974-10-01

    Cell-free extracts of cucumber (Cucumis sativus L. cv. National Pickling) seedlings were found to have amine oxidase activity when assayed with tryptamine as a substrate. Studies of the effect of lowered pH on the extract indicated that this activity was heterogeneous, and three amine oxidases could be separated by ion exchange chromatography. The partially purified enzymes were tested for their activities with several substrates and for their sensitivities to various amine oxidase inhibitors. One of the enzymes may be a monoamine oxidase, although it is inhibited by some diamine oxidase inhibitors. The other two enzymes have properties more characteristic of the diamine oxidases. The possible relationship of the amine oxidases to indoleacetic acid biosynthesis in cucumber seedlings is discussed.

  10. Fungi causing dying out of heather seedlings

    Directory of Open Access Journals (Sweden)

    Maria Kowalik

    2012-12-01

    Full Text Available The aim of the study was to determine the fungi causing dying out of one-yearold heather seedlings. Observations were carried out on: 'Amethyst', 'Annemarie', 'Colette', 'Perestroika' and 'Reini'. The shoots revealing necrotic symptoms were plated on PDA medium. 25 species of fungi were isolated. Among them Pestalotia sydowiana, Alternaria alternata, Cylindrocarpon destructans, Leptosphaeria coniothyrium and Epicoccum purpurascens were dominant, while Mammaria echinobotryoides, Phoma leveillei, Kaissleriella subalpina, Botrytis cinerea and Phytophthora cinnamomi occurred less frequently.

  11. Fungi causing dying out of heather seedlings

    OpenAIRE

    Maria Kowalik; Agnieszka Wandzel

    2012-01-01

    The aim of the study was to determine the fungi causing dying out of one-yearold heather seedlings. Observations were carried out on: 'Amethyst', 'Annemarie', 'Colette', 'Perestroika' and 'Reini'. The shoots revealing necrotic symptoms were plated on PDA medium. 25 species of fungi were isolated. Among them Pestalotia sydowiana, Alternaria alternata, Cylindrocarpon destructans, Leptosphaeria coniothyrium and Epicoccum purpurascens were dominant, while Mammaria echinobotryoides, Phoma leveille...

  12. 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.

  13. CANONICAL CORRELATION OF PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE WOOD OF Eucalyptus grandis AND Eucalyptus saligna CLONES

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Trugilho

    2003-01-01

    Full Text Available The analysis of canonical correlation measures the existence and the intensity of the association between two groups of variables. The research objectified to evaluate thecanonical correlation between chemical and physical characteristics and fiber dimensional ofwood of Eucalyptus grandis and Eucalyptus saligna clones, verifying the interdependenceamong the groups of studied variables. The analysis indicated that the canonical correlationswere high and that in two cases the first and second pair were significant at the level of 1% ofprobability. The analysis of canonical correlation showed that the groups are notindependent. The intergroup associations indicated that the wood of high insoluble lignin contentand low ash content is associated with the high radial and tangential contraction and highbasic density wood.

  14. Genetic diversity of Brazilian natural populations of Anthonomus grandis Boheman (Coleoptera: Curculionidae), the major cotton pest in the New World.

    Science.gov (United States)

    Martins, W F S; Ayres, C F J; Lucena, W A

    2007-01-01

    Twenty-five RAPD loci and 6 isozyme loci were studied to characterize the genetic variability of natural populations of Anthonomus grandis from two agroecosystems of Brazil. The random-amplified polymorphic DNA data disclosed a polymorphism that varied from 52 to 84% and a heterozygosity of 0.189 to 0.347. The index of genetic differentiation (GST) among the six populations was 0.258. The analysis of isozymes showed a polymorphism and a heterozygosity ranging from 25 to 100% and 0.174 to 0.277, respectively. The genetic differentiation (FST) among the populations obtained by isozyme data was 0.544. It was possible to observe rare alleles in the populations from the Northeast region. The markers examined allowed us to distinguish populations from large-scale, intensive farming region (cotton belts) versus populations from areas of small-scale farming

  15. Micromorfologia foliar na análise da fitotoxidez por glyphosate em Eucalyptus grandis Leaf micromorphology in the analysis of glyphosate toxicity in Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2009-01-01

    Full Text Available Foram avaliados os efeitos da deriva de formulações comerciais de glyphosate sobre a superfície foliar e o crescimento de clones de eucalipto. Mudas de seis clones foram submetidas a 129,6 g ha-1 de glyphosate das formulações comerciais Scout®, Roundup NA®, Roundup transorb® e Zapp QI®. Entre os clones não foram identificadas diferenças quanto à tolerância ao glyphosate. Plantas expostas à deriva simulada de Roundup transorb® e Zapp QI® apresentaram, respectivamente, a maior e menor porcentagem de intoxicação. Observou-se menor massa seca em plantas expostas ao glyphosate, independentemente da formulação, e menor altura naquelas expostas ao Scout® e ao Roundup transorb®. As características quantitativas da superfície foliar não foram afetadas pelo glyphosate. As alterações micromorfológicas ocorreram na ausência de danos visíveis e foram observadas em ambas as faces da epiderme, em todos os clones avaliados. Danos como erosão e aspecto amorfo das ceras epicuticulares e infestação por hifas fúngicas ocorreram, independentemente da formulação utilizada. A avaliação anatômica da superfície foliar foi relevante para descrição e interpretação dos danos causados pelo glyphosate. Os dados de crescimento e de intoxicação indicam o Zapp QI® como a formulação de menor risco para a cultura do eucalipto quanto aos efeitos indesejáveis da deriva.The effects of commercial glyphosate drift on the leaf surface and growth of eucalypt clones were evaluated. Seedlings of six clones were submitted to 129.6 g ha-1 sub-rate of commercial glyphosate formulations Scout®, Roundup NA®, Roundup transorb® and Zapp QI®. No differences in tolerance to glyphosate were observed among the clones. Plants exposed to simulated drift of Roundup transorb® and Zapp QI® presented the highest and lowest intoxication percentages, respectively. Plants exposed to glyphosate reduced dry biomass, regardless of the formulation, and also

  16. 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.

  17. 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.

  18. 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

  19. Citrus cyopreservation: viability of diverse taxa and histological observations

    Science.gov (United States)

    Diverse citrus cultivars maintained clonally within gene banks serve as valuable resources for research and breeding programs worldwide. These critical collections are kept as trees within field, screenhouse, or greenhouse collections. These ex situ collections are at risk of being lost due to unfor...

  20. Energy requirement and economic analysis of citrus production in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Ozkan, Burhan E-mail: bozkan@akdeniz.edu.tr; Akcaoz, Handan; Karadeniz, Feyza

    2004-07-01

    The aim of this research was to examine the energy requirements of the inputs and output in citrus production in the Antalya province of Turkey. Data for the production of citrus fruits (orange, lemon and mandarin) were collected from 105 citrus farms by using a face to face questionnaire method. The research results revealed that lemon production was the most energy intensive among the three fruits investigated. The energy input of chemical fertilizer (49.68%), mainly nitrogen, has the biggest share in the total energy inputs followed by Diesel (30.79%). The lemon production consumed a total of 62 977.87 MJ/ha followed by orange and mandarin with 60 949.69 and 48 838.17 MJ/ha, respectively. The energy ratios for orange, mandarin and lemon were estimated to be 1.25, 1.17 and 1.06, respectively. On average, the non-renewable form of energy input was 95.90% of the total energy input used in citrus production compared to only 3.74% for the renewable form. The benefit-cost ratio was the highest in orange production (2.37) followed by lemon. The results indicate that orange production in the research area is most remunerative to growers compared to lemon and mandarin.

  1. Efficiency of chemotherapy coupled with thermotherapy against citrus HLB

    Science.gov (United States)

    Six independent experiments were carried out to evaluate the effectiveness of the chemotherapy coupled with the thermotherapy on pot-contained HLB-affected plants based on our previous results from graft-based methods. Three-year old potted HLB-affected citrus plants were exposed to 4 thermotherapy ...

  2. Longevity of radiofrequency identification device microchips in citrus trees

    Science.gov (United States)

    Long-term identification of individual plants in the field is an important part of many types of botanical and horticultural research. In a previous report, we described methods for using implanted radiofrequency (RFID) microchips to tag citrus trees for field research. This report provides an upd...

  3. Volatile flavour components of grapefruit juice (Citrus paradisi Macfadyen)

    NARCIS (Netherlands)

    Nunez, A.J.; Maarse, H.; Bemelmans, J.M.H.

    1985-01-01

    The qualitative analysis of volatile flavour components in grapefruit juice (Citrus paradisi Macfadyen) was performed using a gas chromatography/mass spectro‐metry/computer system which allowed the identification of 58 components, 25 of them being reported for the first time. The aroma concentrates

  4. Measurements on hydrocyanic acid absorbed by citrus tissues during fumigation

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, E.T.; Sinclair, W.B.; Lindgren, D.L.

    1942-05-01

    Methods for the accurate determination of hydrocyanic acid (HCN) and studies of factors affecting the recovery of HCN from fumigated citrus tissues have been previously reported. This study is concerned with the results of the application of the principles derived from the earlier studies to further laboratory experiments, performed in conjunction with the fumigation studies of citrus trees under orchard conditions. The effect of certain factors, such as oil sprays, the locality in which the trees were grown, and the temperature, age, and moisture content of citrus tissues at time of fumigation, have been studied in relation to the absorption and retention of HCN under both laboratory and field conditions. The comparative amounts of absorption and lengths of time of retention of HCN have also been studied in relation to maturity of leaves and fruits and in relation to their injurious or noninjurious effects. The results of laboratory experiments cannot always be applied directly to the solution of orchard fumigation problems, but they may serve as a basis for the formulation of field experiments. The trees, leaves, and fruits used in the experiments described in this study were of the Valencia-orange variety (Citrus sinensis Osbeck). 13 references, 9 figures, 11 tables.

  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. 7 CFR 319.56-41 - Citrus from Peru.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Citrus from Peru. 319.56-41 Section 319.56-41 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Fruits and Vegetables § 319.56-41...

  7. Evaluation of citrus fibers as a tablet excipient.

    Science.gov (United States)

    Cespi, Marco; Bonacucina, Giulia; Roberts, Matthew; Hanson, Samuel; Jones, Stephen; Makevica, Elina; Casettari, Luca; Palmieri, Giovanni Filippo

    2014-04-01

    The consumption of fibers is associated with many health benefits, such as a reduction of cardiovascular and gastrointestinal diseases, control of body weight, and prevention of diabetes. Despite the widespread use of fiber supplements such as capsules or tablets, there is an almost complete lack of information concerning the technological properties of functional fibers used in nutraceutical formulations. The aim of this work was to characterize the technological properties of citrus fibers necessary for their use as a processing aid in tableting. The results obtained showed that citrus fibers share many properties of other polysaccharides used as tableting excipients, such as thermal behavior and compaction mechanism, together with an appreciable tabletability. However, the most interesting properties resulted from their disintegration power. Citrus fibers behaved in a similar manner to the well-known super disintegrant croscarmellose sodium and resulted to be little susceptible to their concentration, to lubricant type, and lubricant concentration. Thus, this work supports the idea of a potential use of citrus fibers as "active" substances and processing aid in the tableting of nutraceutical products and also as functional excipient in pharmaceutical tablets formulation.

  8. Micro-irrigation systems, automation and fertigation in citrus

    Directory of Open Access Journals (Sweden)

    Parameshwar Sidramappa Shirgure

    2012-11-01

    Full Text Available Citrus is number one group of fruits grown in more than 140 countries in the world. Micro-irrigation systems and fertigation management is one of the main concerns of the modem citrus fruit production irrespective of availability of soil, water and fertilizer resources. A variety of recommendations have emerged world over on irrigation systems and fertigation based on soil and leaf analysis of the nutrients, evapo-transpiration and water use pattern. The research review of literature has revealed best promising results on irrigation scheduling based on depletion pattern of soil available water content, irrigation systems and fertigation. Various micro-irrigation systems have established their superiority over traditionally used flood irrigation with micro-jets having little edge over rest of the others. Similarly, fertigation has shown good responses on growth, yield, quality and uniform distribution pattern of applied nutrients within the plant rootzone compared to band placement involving comparatively localized fertilization. Automated fertigation in citrus orchards is a new concept, which would be the only solitary choice amongst many irrigation monitoring methods in near future. The present status of the review on micro-irrigation and fertigation in citrus cultivars is clearly indicated in this article.

  9. 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.

  10. Antimycotic Activity and Genotoxic Evaluation of Citrus sinensis and Citrus latifolia Essential Oils

    Science.gov (United States)

    Ruiz-Pérez, Nancy J.; González-Ávila, Marisela; Sánchez-Navarrete, Jaime; Toscano-Garibay, Julia D.; Moreno-Eutimio, Mario A.; Sandoval-Hernández, Teresa; Arriaga-Alba, Myriam

    2016-01-01

    The aim of this study was to evaluate the antifungal activity of essential oils (EOs) of Citrus sinensis (C. sinensis) and Citrus latifolia (C. latifolia) against five Candida species: Candida albicans, Candida tropicalis, Candida glabrata, Candida lusitaniae and Candida guilliermondii; and perform its genotoxic evaluation. The EOs of C. sinensis and C. latifolia were obtained from the peel by hydro-distillation. The major components determined by GC-MS were in C. sinensis, d-limonene (96%) and α-myrcene (2.79%); and in C. latifolia, d-limonene (51.64%), β-thujene (14.85%), β-pinene (12.79%) and γ-terpinene (12.8%). Antifungal properties were studied by agar diffusion method, where C. sinensis presented low activity and C. latifolia essential oil was effective to inhibit growing of C. lusitaniae and C. guilliermondii with IC50 of 6.90 and 2.92 μg respectively. The minimum inhibitory concentrations (MIC) for C. sinensis were in a range of 0.42–3.71 μg and for C. latifolia of 0.22–1.30 μg. Genotoxic evaluation was done by Ames test where none of the oils induced point mutations. Flow cytometry was used to measure toxicity in human oral epithelial cells, C. sinensis was not cytotoxic and C. latifolia was toxic at 21.8 μg. These properties might bestow different odontological applications to each essential oil. PMID:27137128

  11. Antidiabetic, antihyperlipidemic and antioxidant potential of methanol extract ofTectona grandis flowers in streptozotocin induced diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Subramaniam Ramachandran; Aiyalu Rajasekaran; KT Manisenthil Kumar

    2011-01-01

    Objective:To investigate antidiabetic, antihyperlipidemic and antioxidant activity of methanol extract ofTectona grandis (T. grandis) flowers(METGF)in streptozotocin (STZ) induced diabetic rats to supports its traditional use.Methods: Acute toxicity study of METGF was carried out in rat to determine its dose for the antidiabetic study. Oral glucose tolerance test(OGTT) was performed to evaluateMETGF effect on elevated blood glucose level. Diabetes was induced in rats by administration ofSTZ(60 mg/kg, ip.) and it was confirmed 72 h after induction.METGF was orally given to the diabetic rats up to28 days and blood glucose level were estimated each week. On28 day of the experiment, diabetic rats were sacrificed after the blood collection for the biochemical parameters analysis and liver, kidney was collected to determine antioxidants levels.Results:In acute toxicity,METGFdid not show toxicity and death up to a dose 2 000mg/kg in rats. Administration ofMETGF 100 and200mg/kg significantly (P<0.001) reduced blood glucose levels inOGTTand STZ-induced diabetic rats. Both doses ofMETGF treatment significantly (P<0.001, P<0.01 andP<0.05) increased body weight, serum insulin, haemoglobin (Hb) and total protein levels in diabetic rats. Also,MEGTF treatment reduced elevated glycosylated haemoglobin(HbA1c) and other biochemical parameters levels significantly (P<0.001) in diabetic rats. Altered lipid profiles and antioxidants levels were reversed to near normal in diabetic rats treated withMETGF. Conclusions: These results concluded that METGF possesses antidiabetic, antihyperglycemic and antioxidant activity which supports its traditional use.

  12. IDENTIFICAÇÃO E CARACTERIZAÇÃO DA ENTOMOFAUNA EM PLANTIOS DE TECA (Tectona grandis

    Directory of Open Access Journals (Sweden)

    SILVA, Carla Vanessa Moraes da

    2013-10-01

    Full Text Available The presence of pest insects with potential damages and losses on teak plantation, Tectona grandis, is relevant due to the economic criterion which requires high costs for managing. Therefore, the necessity of knowing about the insect fauna of plant protection importance has gained importance, such as the soil termite, field cricket, black cutworm, Saúva-lemon, Caterpillars-to-teak, Catepillar-queimadeira and others that reduce the production. Thus, this study aimed to add to the existing literature new information about the biological and morphological aspects, damages and methods to control the major pests of Teak, which may assist the crop management. A presença de insetos-pragas com potencial de dano e de perdas na cultura da teca, Tectona grandis, é relevante devido ao critério econômico que requer altos custos com seu manejo. Sendo assim, acentua-se a necessidade do conhecimento sobre a entomofauna de importância fitossanitária para a cultura, tais como o cupim do solo, grilo-comum, lagarta-rosca, saúva-limão, lagarta-da-teca, lagarta-queimadeira e demais coleobrocas que reduzem sua produção. Assim, o objetivo desse estudo foi acrescentar à bibliografia existente novas informações sobre os aspectos biológicos, morfológicos, injúrias e táticas de controle das principais pragas da cultura da Teca, as quais podem auxiliar no manejo da cultura.

  13. Potensi Kayu Perkakas dan Kayu Bakar Jenis Jati (Tectona grandis di Hutan Rakyat Desa Natah, Gunung Kidul

    Directory of Open Access Journals (Sweden)

    Ris Hadi Purwanto

    2009-07-01

    Full Text Available Potentials  of Merchantable Timber and Firewod of Teak (Tectona grandis in Natah Village Community Forest , Gunungkidul The potential of merchantable timber and firewod of teak (Tectona grandis in Desa Natah community forest was estimated by developing allometric equations method. To establish the allometric equation 350 sample trees were measured to determine the relationships between tree height (H and diameter breast height (D. Thirty trees of various sizes were cut to measure the merchantable timber and firewood volume. The raw merchantable timber volume of teak in the community forest was defined as the ligneous material contained in the bole and branches which both with a diameter of at least 10cm. The result showed that D (taken at about 1.3m above the ground was a good predictor of H with r2 over 0.9672. When D was combined with H, r2 was improved somewhat for the merchantable timber volume, suggesting the growth patterns of tree dimensions were colesy interdependent. A standing stock of the merchantable timber and firewood volume of teak in the community forest was then estimated based on the allometric relations. Proportions of the merchantable timber and firewood volume were 66.91% and 33.09% of total wood volume per tree, respectively. The potential of merchantable timber and firewood volume in these community forest were 13.501 m3/ha and 8.686 m3/ha, respectively, with a basal area of 1.887 m2/ha. Based on the basal area, Desa Natah community forests of teak could be classified into extremely sparse of stands category.

  14. Citrus orchards management and soil water repellency in Eastern Spain

    Science.gov (United States)

    Cerdà, A.; González Peñaloza, F. A.; Jordán, A.; Zavala, L. M.

    2012-04-01

    Water repellent soils are found around the world, although originally was found on fire affected soil (DeBano, 1981). However, for decades, water repellency was found to be a rare soil property. One of the pioneer research that shown that water repellency was a common soil property is the Wander (1949) publication in Science. Wander researched the water repellency on citrus groves, and since then, no information is available about the water repellency on citrus plantations. The Mediterranean soils are prone to water repellency due to the summer dry conditions (Cerdà and Doerr, 2007). And Land Use and Land Management are key factors (Harper et al., 2000; Urbanek et al., 2007) to understand the water repellency behaviour of agriculture soils. Valencia region (Eastern Spain) is the largest exporter in the world and citrus plantations located in the alluvial plains and fluvial terraces are moving to alluvial fans and slopes where the surface wash is very active (Cerdà et al., 2009). This research aims to show the water repellency on citrus orchards located on the sloping terrain (water repellency in citrus orchards under different managements: annual addition of plant residues and manure with no tilling and no fertilizer (MNT), annual addition of plant residues with no tillage (NT), application of conventional herbicides and no tilling (HNT) and conventional tillage in June (CT). The period for each type of management ranged from 2 and 27 (MNT), 1 and 25 (NT), 2 and 27 (HNT) and 3 and 29 years (CT). At each plot, a ten points were selected every 10 cm along inter-rows and water drop penetration time test (WDTP; DeBano, 1981) was performed. The results show that the MNT treatment induced slight water repellency in citrus-cropped soils compared to other treatments. Small but significant soil water repellency was observed under NT and HNT treatments (mean WDTP 4 ± 4 s and 2 ± 2 s, respectively), which may be regarded as subcritical soil water repellency. Slight water

  15. MODELOS PREDICTIVOS DE BIOMASA AÉREA DE Eucalyptus grandis PARA EL NORESTE DE ARGENTINA

    Directory of Open Access Journals (Sweden)

    Rosa Angela Winck

    2015-01-01

    Full Text Available Diferentes intereses industriales, energéticos y ambientales han motivado el análisis de las distintas posibilidades de aprovechamiento de la biomasa forestal, este tema está adquiriendo un creciente protagonismo, por lo que la cuantificación de la biomasa aérea de estos sistemas forestales constituye un primer paso fundamental e ineludible. El objetivo de este trabajo fue desarrollar modelos que permitan estimar la biomasa de los diferentes compartimentos aéreos de Eucalyptus grandis . Para ello se emplearon datos de 41 árboles provenientes de rodales de diferentes edades, entre 4 y 32 años, ubicados en la región NE de Argentina. Se tomaron 23 individuos ubicados en la Zona Norte y Alta de Misiones (zona 1 y 18 en el Sur de Misiones y NE de Corrientes (zona 2. Se determinó la biomasa de hojas, ramas menores a 5 cm, ramas mayores a 5 cm, total de ramas, fuste y biomasa total del árbol. Para el ajuste de modelos se tomaron diversas variables independientes, el diámetro a la altura de pecho (dap, la altura total del árbol (h, el producto (dap 2 *h y la variable “ dummy” (zona. Para el caso de la biomasa de ramas y de hojas, debido a que no se lograron resultados satisfactorios con el empleo de estas variables, se examinaron modelos que adicionaban índice de sitio, factor de espaciamiento, diámetro en la base de la copa verde (dbcv, altura hasta la base de la copa verde (hbcv, longitud de copa verde (lcv, el área transversal de albura en la base de copa verde (g Alb bcv y diferentes combinaciones de estas variables. Los modelos fueron seleccionados en base al coeficiente de determinación y el error cuadrático medio. Para la biomasa de ramas menores a 5 cm, ramas mayores a 5 cm, total de ramas, fuste y total, los mejores modelos fueron los que incorporaron como variables regresoras, el diámetro a la altura de pecho, la altura total del árbol y la variable “ dummy” (zona. Para la biomasa de hojas, las variables, edad,

  16. Stylet morphometrics and citrus leaf vein structure in relation to feeding behavior of the Asian citrus psyllid Diaphorina citri, vector of citrus huanglongbing bacterium.

    Science.gov (United States)

    Ammar, El-Desouky; Hall, David G; Shatters, Robert G

    2013-01-01

    The Asian citrus psyllid (ACP), Diaphorina citri (Hemiptera: Psyllidae), is the primary vector of the phloem-limited bacterium Candidatus Liberibacter asiaticus (LAS) associated with huanglongbing (HLB, citrus greening), considered the world's most serious disease of citrus. Stylet morphometrics of ACP nymphs and adults were studied in relation to citrus vein structure and to their putative (histologically verified) feeding sites on Valencia orange leaves. ACP nymphs preferred to settle and feed on the lower (abaxial) side of young leaves either on secondary veins or on the sides of the midrib, whereas adults preferred to settle and feed on the upper (adaxial) or lower secondary veins of young or old leaves. Early instar nymphs can reach and probe the phloem probably because the distance to the phloem is considerably shorter in younger than in mature leaves, and is shorter from the sides of the midrib compared to that from the center. Additionally, the thick-walled 'fibrous ring' (sclerenchyma) around the phloem, which may act as a barrier to ACP stylet penetration into the phloem, is more prominent in older than in younger leaves and in the center than on the sides of the midrib. The majority (80-90%) of the salivary sheath termini produced by ACP nymphs and adults that reached a vascular bundle were associated with the phloem, whereas only 10-20% were associated with xylem vessels. Ultrastructural studies on ACP stylets and LAS-infected leaves suggested that the width of the maxillary food canal in first instar nymphs is wide enough for LAS bacteria to traverse during food ingestion (and LAS acquisition). However, the width of the maxillary salivary canal in these nymphs may not be wide enough to accommodate LAS bacteria during salivation (and LAS inoculation) into host plants. This may explain the inability of early instar nymphs to transmit LAS/HLB in earlier reports.