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Sample records for black root rot

  1. Evaluation of rhizobacterial indicators of tobacco black root rot suppressiveness in farmers' fields

    Czech Academy of Sciences Publication Activity Database

    Kyselková, Martina; Almario, J.; Kopecký, J.; Ságová-Marečková, M.; Haurat, J.; Muller, D.; Grundmann, G.L.; Moënne-Loccoz, Y.

    2014-01-01

    Roč. 6, č. 4 (2014), s. 346-353. ISSN 1758-2229 Institutional support: RVO:60077344 Keywords : rhizobacterial indicators * tobacco black root rot suppressiveness * farmers' fields Subject RIV: EH - Ecology, Behaviour Impact factor: 3.293, year: 2014

  2. Cyanide production by Pseudomonas fluorescens helps suppress black root rot of tobacco under gnotobiotic conditions

    OpenAIRE

    Voisard, Christophe; Keel, Christoph; Haas, Dieter; Dèfago, Geneviève

    1989-01-01

    Pseudomonas fluorescens CHA0 suppresses black root rot of tobacco, a disease caused by the fungus Thielaviopsis basicola. Strain CHA0 excretes several metabolites with antifungal properties. The importance of one such metabolite, hydrogen cyanide, was tested in a gnotobiotic system containing an artificial, iron-rich soil. A cyanidenegative (hcn) mutant, CHA5, constructed by a gene replacement technique, protected the tobacco plant less effectively than did the wild-type CHA0. Complementation...

  3. Integrated options for the management of black root rot of strawberry caused by Rhizoctonia solani Kuhn.

    Science.gov (United States)

    Asad-Uz-Zaman, Md; Bhuiyan, Mohammad Rejwan; Khan, Mohammad Ashik Iqbal; Alam Bhuiyan, Md Khurshed; Latif, Mohammad Abdul

    2015-02-01

    An investigation was made to manage strawberry black root rot caused by Rhizoctonia solani (R. solani) through the integration of Trichoderma harzianum (T. harzianum) isolate STA7, mustard oil cake and Provax 200. A series of preliminary experiments were conducted to select a virulent isolate of R. solani, an effective isolate of T. harzianum, a suitable organic amendment, and a suitable fungicide before setting the experiment for integration. The pathogenicity of the selected four isolates of R. solani was evaluated against strawberry and isolate SR1 was selected as the test pathogen due to its highest virulent (95.47% mortality) characteristics. Among the 20 isolates of T. harzianum, isolate STA7 showed maximum inhibition (71.97%) against the test pathogen (R. solani). Among the fungicides, Provax-200 was found to be more effective at lowest concentration (100 ppm) and highly compatible with Trichoderma isolates STA7. In the case of organic amendments, maximum inhibition (59.66%) of R. solani was obtained through mustard oil cake at the highest concentration (3%), which was significantly superior to other amendments. Minimum percentages of diseased roots were obtained with pathogen (R. solani)+Trichoderma+mustard oil cake+Provax-200 treatment, while the highest was observed with healthy seedlings with a pathogen-inoculated soil. In the case of leaf and fruit rot diseases, significantly lowest infected leaves as well as fruit rot were observed with a pathogen+Trichoderma+mustard oil cake+Provax-200 treatment in comparison with the control. A similar trend of high effectiveness was observed by the integration of Trichoderma, fungicide and organic amendments in controlling root rot and fruit diseases of strawberry. Single application of Trichoderma isolate STA7, Provax 200 or mustard oil cake did not show satisfactory performance in terms of disease-free plants, but when they were applied in combination, the number of healthy plants increased significantly. The

  4. Evaluation of rhizobacterial indicators of tobacco black root rot suppressiveness in farmers' fields.

    Science.gov (United States)

    Kyselková, Martina; Almario, Juliana; Kopecký, Jan; Ságová-Marečková, Markéta; Haurat, Jacqueline; Muller, Daniel; Grundmann, Geneviève L; Moënne-Loccoz, Yvan

    2014-08-01

    Very few soil quality indicators include disease-suppressiveness criteria. We assessed whether 64 16S rRNA microarray probes whose signals correlated with tobacco black root rot suppressiveness in greenhouse analysis could also discriminate suppressive from conducive soils under field conditions. Rhizobacterial communities of tobacco and wheat sampled in 2 years from four farmers' fields of contrasted suppressiveness status were compared. The 64 previously identified indicator probes correctly classified 72% of 29 field samples, with nine probes for Azospirillum, Gluconacetobacter, Sphingomonadaceae, Planctomycetes, Mycoplasma, Lactobacillus crispatus and Thermodesulforhabdus providing the best prediction. The whole probe set (1033 probes) revealed strong effects of plant, field location and year on rhizobacterial community composition, and a smaller (7% variance) but significant effect of soil suppressiveness status. Seventeen additional probes correlating with suppressiveness status in the field (noticeably for Agrobacterium, Methylobacterium, Ochrobactrum) were selected, and combined with the nine others, they improved correct sample classification from 72% to 79% (100% tobacco and 63% wheat samples). Pseudomonas probes were not informative in the field, even those targeting biocontrol pseudomonads producing 2,4-diacetylphloroglucinol, nor was quantitative polymerase chain reaction for 2,4-diacetylphloroglucinol-synthesis gene phlD. This study shows that a subset of 16S rRNA probes targeting diverse rhizobacteria can be useful as suppressiveness indicators under field conditions. PMID:24992533

  5. Disease notes - Bacterial root rot

    Science.gov (United States)

    Bacterial root rot initiated by lactic acid bacteria, particularly Leuconostoc, occurs every year in Idaho sugarbeet fields. Hot fall weather seems to make the problem worse. Although Leuconostoc initiates the rot, other bacteria and yeast frequently invade the tissue as well. The acetic acid bac...

  6. Assessment of the relationship between geologic origin of soil, rhizobacterial community composition and soil receptivity to tobacco black root rot in Savoie region (France)

    Czech Academy of Sciences Publication Activity Database

    Almario, J.; Kyselková, Martina; Kopecký, J.; Ságová-Marečková, M.; Muller, D.; Grundmann, G.L.; Moënne-Loccoz, Y.

    2013-01-01

    Roč. 371, 1/2 (2013), s. 397-408. ISSN 0032-079X Grant ostatní: MŚMT(CZ) ME09077 Institutional support: RVO:60077344 Keywords : suppressive soils * Thielaviopsis basicola * black root rot Subject RIV: EE - Microbiology, Virology Impact factor: 3.235, year: 2013

  7. Etiology of phomopsis root rot in soybean

    Directory of Open Access Journals (Sweden)

    Valéria Cecília Ghissi

    2014-09-01

    Full Text Available In a survey of damages caused by soybean root rot to crops in the south of Brazil for several years, a root rot caused by Phomopsis sp has been found with increasing frequency. The primary symptoms are seen when the main root is cut longitudinally, including the death of the wood which shows white coloration and well-defined black lines that do not have a defined format. Thus, based on similarity, it has been called geographic root rot due to its aspect resembling irregular lines that separate regions on a map. In isolations, colonies and alpha spores of Phomopsis have prevailed. Pathogenicity test was done by means of inoculation in the crown of plants cultivated in a growth chamber. The geographic symptoms were reproduced in plants and the fungus Phomopsis sp. was reisolated. In soybean stems naturally infected with pod and stem blight, geographic symptoms caused by Phomopsis phaseoli are found. To the known symptoms on stems, pods and grains, that of root rot caused by P. phaseoli is now added.

  8. Rhizoctonia root rot of lentil

    Science.gov (United States)

    Rhizoctonia root rot is a soilborne disease of lentil caused by the fungal pathogen Rhizoctonia solani, and is favored by cool (11-19 C or 52 - 66 F) and wet soil conditions. The disease starts as reddish or dark brown lesions on lentil plants near the soil line, and develops into sunken lesions an...

  9. Transgenic sweet potato expressing thionin from barley gives resistance to black rot disease caused by Ceratocystis fimbriata in leaves and storage roots.

    Science.gov (United States)

    Muramoto, Nobuhiko; Tanaka, Tomoko; Shimamura, Takashi; Mitsukawa, Norihiro; Hori, Etsuko; Koda, Katsunori; Otani, Motoyasu; Hirai, Masana; Nakamura, Kenzo; Imaeda, Takao

    2012-06-01

    Black rot of sweet potato caused by pathogenic fungus Ceratocystis fimbriata severely deteriorates both growth of plants and post-harvest storage. Antimicrobial peptides from various organisms have broad range activities of killing bacteria, mycobacteria, and fungi. Plant thionin peptide exhibited anti-fungal activity against C. fimbriata. A gene for barley α-hordothionin (αHT) was placed downstream of a strong constitutive promoter of E12Ω or the promoter of a sweet potato gene for β-amylase of storage roots, and introduced into sweet potato commercial cultivar Kokei No. 14. Transgenic E12Ω:αHT plants showed high-level expression of αHT mRNA in both leaves and storage roots. Transgenic β-Amy:αHT plants showed sucrose-inducible expression of αHT mRNA in leaves, in addition to expression in storage roots. Leaves of E12Ω:αHT plants exhibited reduced yellowing upon infection by C. fimbriata compared to leaves of non-transgenic Kokei No. 14, although the level of resistance was weaker than resistance cultivar Tamayutaka. Storage roots of both E12Ω:αHT and β-Amy:αHT plants exhibited reduced lesion areas around the site inoculated with C. fimbriata spores compared to Kokei No. 14, and some of the transgenic lines showed resistance level similar to Tamayutaka. Growth of plants and production of storage roots of these transgenic plants were not significantly different from non-transgenic plants. These results highlight the usefulness of transgenic sweet potato expressing antimicrobial peptide to reduce damages of sweet potato from the black rot disease and to reduce the use of agricultural chemicals. PMID:22212462

  10. Rhizoctonia seed, seedling, and wet root rot

    Science.gov (United States)

    Wet root rot caused by Rhizoctonia solani Kühn can cause seed and seedling rot of both lentil and chickpea as well as many other agricultural crops worldwide. The pathogen is favored in cool, sandy soil with high organic matter under no-till or reduced-till soil management practices. Survival spor...

  11. Heterobasidion root rot in Norway spruce

    OpenAIRE

    Thor, Magnus

    2005-01-01

    In spite of its biological and economic impact on Swedish forestry, root rot caused by Heterobasidion annosum (Fr.) Bref. sensu lato has received no or little attention in forest planning. This thesis summarizes and discusses two experiments involving prophylactic treatment of stumps, and three investigations on the modelling and simulation of root rot in coniferous stands with special emphasis on Norway spruce (Picea abies [L.] Karst.). In 14 previously unthinned stands of Norway spruce, the...

  12. Rhizoctonia damping-off stem canker and root rot

    Science.gov (United States)

    Rhizoctonia solani has been reported to cause damping-off and root rot of rhododendrons and azaleas. Damping-off often includes groups of dying and dead seedlings. Decline of rooted plants in containers results from both root rot and stem necrosis below or above the soil line. Root rot is usually no...

  13. Cultivar Selection for Sugar Beet Root Rot Resistance

    Science.gov (United States)

    Fungal and bacterial root rots in sugar beet caused by Rhizoctonia solani (Rs) and Leuconostoc mesenteroides subsp. dextranicum (Lm) can lead to root yield losses greater than 50%. To reduce the impact of these root rots on sucrose loss in the field, storage, and factories, studies were conducted t...

  14. Endophytic bacteria from Piper tuberculatum Jacq.: isolation, molecular characterization, and in vitro screening for the control of Fusarium solani f. sp piperis, the causal agent of root rot disease in black pepper (Piper nigrum L.).

    Science.gov (United States)

    Nascimento, S B; Lima, A M; Borges, B N; de Souza, C R B

    2015-01-01

    Endophytic bacteria have been found to colonize internal tissues in many different plants, where they can have several beneficial effects, including defense against pathogens. In this study, we aimed to identify endophytic bacteria associated with roots of the tropical piperaceae Piper tuberculatum, which is known for its resistance to infection by Fusarium solani f. sp piperis, the causal agent of black pepper (Piper nigrum) root rot disease in the Amazon region. Based on 16S rRNA gene sequence analysis, we isolated endophytes belonging to 13 genera: Bacillus, Paenibacillus, Pseudomonas, Enterobacter, Rhizobium, Sinorhizobium, Agrobacterium, Ralstonia, Serratia, Cupriavidus, Mitsuaria, Pantoea, and Staphylococcus. The results showed that 56.52% of isolates were associated with the phylum Proteobacteria, which comprised α, β, and γ classes. Other bacteria were related to the phylum Firmicutes, including Bacillus, which was the most abundant genus among all isolates. Antagonistic assays revealed that Pt12 and Pt13 isolates, identified as Pseudomonas putida and Pseudomonas sp, respectively, were able to inhibit F. solani f. sp piperis growth in vitro. We describe, for the first time, the molecular identification of 23 endophytic bacteria from P. tuberculatum, among which two Pseudomonas species have the potential to control the pathogen responsible for root rot disease in black pepper in the Amazon region. PMID:26214435

  15. Root rot diseases of sugar beet

    Directory of Open Access Journals (Sweden)

    Jacobsen Barry J.

    2006-01-01

    Full Text Available Root rot diseases of sugar beet caused by Rhizoctonia solani (AG 2-2 IIIB and AG 2-2 IV, R. crocorum, Aphanomyces cochlioides, Phoma betae, Macrophomina phaeseolina, Fusarium oxysporum f.sp. radicis-betae, Pythium aphanidermatum Phytophthora drechsleri, Rhizopus stolonifer, R. arrhizus and Sclerotium rolfsii cause significant losses wherever sugar beets are grown. However, not all these soil-borne pathogens have been reported in all sugar beet production areas. Losses include reduced harvestable tonnage and reduced white sugar recovery. Many of these pathogens also cause post harvest losses in storage piles. Control for diseases caused by these pathogens include disease resistant cultivars, avoidance of stresses, cultural practices such as water management and the use of fungicides.

  16. Stand tending and root rot in Norway spruce stands - economical effects caused by root rot at different thinning regimes

    International Nuclear Information System (INIS)

    This report is divided into three parts: 1) a literature study describing the most common fungi causing rot in wood and descriptions of various strategies to reduce economic loss from root rot, 2) a check of a model describing the development of butt rot in pure Norway spruce plantations in southern Sweden, and 3) simulated economic effects of root rot in stands with various stand tending. The rot model was used to estimate future rot frequencies in the economic calculations. In order to avoid overestimations of rot frequencies, the calculations were also executed when assuming slower growth of rot than shown in the model. When analysing the economical effects of rot, the following three thinning programmes were used: Program 1: thinning at the ages of 30- and 45 years. Final felling at the ages 50-, 55-, 60-, 65-, and 70 years. Program 2: thinning at the ages of 40- and 60- years. Final felling at the ages 65 and 75 years. Program 3: thinning at the ages of 30-, 40-, 55-, and 70 years. Final felling at the ages 80 and 90 years. With an interest rate of 3%, programme 2 (final felling at the age of 65 years) had the highest value at present. This result was valid when presuming butt rot in the stand as well as when presuming no butt rot in the stand. There was a small difference between the value at present in programme 1 (final felling at the age of 60 years) and in programme 3 (final felling at the age of 80 years). When presuming butt rot in the stand, the value at present in programme 3 decreased somewhat more in comparison to the value at present in programme 1. Compared to no butt rot in the stand, the optimal final felling time appeared five to ten years earlier when assuming butt rot in the stand. Stand tending programme 1 and an interest rate of 3% were used. Interest rates 2 and 4% did not indicate shorter rotation. The calculated optimal time of final felling appeared at the same stand age whether assuming rot preset or not. The results in this study

  17. Root rot of sugarbeet in the Vojvodina Province

    Directory of Open Access Journals (Sweden)

    Stojšin Vera B.

    2006-01-01

    Full Text Available Large changes introduced in the sugar beet production technology in the Vojvodina Province over last 40 years resulted in changes in the etiology and harmfulness of different agents of sugar beet root diseases. Improvements in cultivation practices reduced the harmfulness of some diseases while increased the harmfulness of others. Some disease agents became obsolete, but others gained importance. New agents of root diseases were found. The most frequent damages, persisting over long periods of time were caused by seedling damping-off, Fusarium root rot, charcoal root rot, parasitic (Rhizomania and non-parasitic root bearding. The parasitic damping-off caused by several fungal species but most frequently by Phoma betae occurred at the time when multigerm seeds were used in combination with extensive cultural practices. The agents of seedling diseases completely lost their significance as the consequence of switching to fungicide - treated monogerm seeds, earlier planting and improved soil tillage. In the period of intensive use of agricultural chemicals, seedling damping-off occurred frequently due to the phytotoxic action of chemicals (insecticides, herbicides and mineral fertilizers. In some years, frosts caused damping- off of sugar beet seedlings on a large scale in the Vojvodina Province. Poor sugar beet germination and emergence were frequently due to spring droughts. Sometimes they were due to strong winds. The occurrence of Fusarium root rot and charcoal root rot intensified on poor soils. Fusariosis symptoms were exhibited as plant wilting and different forms of root rot. In recent years root tip rot has occurred frequently in the first part of the growing season causing necrosis and dying of plants. Lateral roots tended to proliferate from the healthy tissue, giving the root a bearded appearance similar to Rhizomania. Fusarium oxysporum was the most frequent agent of this fusariosis. F. graminearum, F. equiseti, F. solani have also been

  18. Molecular systematics of the cotton root rot pathogen, Phymatotrichopsis omnivora

    OpenAIRE

    Marek, S.M.; Hansen, K; Romanish, M.; Thorn, R. G.

    2009-01-01

    Cotton root rot is an important soilborne disease of cotton and numerous dicot plants in the south-western United States and Mexico. The causal organism, Phymatotrichopsis omnivora (= Phymatotrichum omnivorum), is known only as an asexual, holoanamorphic (mitosporic) fungus, and produces conidia resembling those of Botrytis. Although the corticoid basidiomycetes Phanerochaete omnivora (Polyporales) and Sistotrema brinkmannii (Cantharellales; both Agaricomycetes) have been suggested as teleomo...

  19. Root rots of common and tepary beans in Puerto Rico

    Science.gov (United States)

    Root rots are a disease complex affecting common bean and can be severe in bean growing areas in the tropics and subtropics. The presence of several pathogens makes it difficult to breed for resistance because of the synergistic effect of the pathogens in the host and the interaction of soil factors...

  20. Molecular systematics of the cotton root rot pathogen, Phymatotrichopsis omnivora

    NARCIS (Netherlands)

    Marek, S.M.; Hansen, K.; Romanish, M.; Thorn, R.G.

    2009-01-01

    Cotton root rot is an important soilborne disease of cotton and numerous dicot plants in the south-western United States and Mexico. The causal organism, Phymatotrichopsis omnivora (= Phymatotrichum omnivorum), is known only as an asexual, holoanamorphic (mitosporic) fungus, and produces conidia res

  1. Trichoderma spp. decrease Fusarium root rot in common bean

    Directory of Open Access Journals (Sweden)

    Hudson Teixeira

    2012-12-01

    Full Text Available The effectiveness of six Trichoderma-based commercial products (TCP in controlling Fusarium root rot (FRR in common bean was assessed under field conditions. Three TCP, used for seed treatment or applied in the furrow, increased seedling emergence as much as the fungicide fludioxonil. FRR incidence was not affected, but all TCP and fludioxonil reduced the disease severity, compared to control. Application of Trichoderma-based products was as effective as that of fludioxonil in FRR management.

  2. Diaporthaceae associated with root rot of maize

    OpenAIRE

    Lamprecht, S.C.; Crous, P.W.; Groenewald, J.Z.; Tewoldemedhin, Y.T.; Marasas, W.F.O.

    2011-01-01

    We investigated the identity and genetic diversity of more than 100 isolates belonging to Phyllosticta (teleomorph Guignardia), with particular emphasis on Phyllosticta citricarpa and Guignardia mangiferae s.l. occurring on Citrus. Phyllosticta citricarpa is the causal agent of Citrus Black Spot and is subject to phytosanitary legislation in the EU. This species is frequently confused with a taxon generally referred to as G. mangiferae, the presumed teleomorph of P. capitalensis, which is a n...

  3. Influence of Rhizoctonia-Bacterial root rot complex on storability of sugar beet

    Science.gov (United States)

    The root rot complex, caused by Rhizoctonia solani and Leuconostoc mesenteroides, can lead to yield loss in the field but may also lead to problems with sucrose loss in storage. Thus, studies were conducted to investigate if placing sugar beet roots suffering from root rot together with healthy roo...

  4. High-throughput sequencing of black pepper root transcriptome

    Directory of Open Access Journals (Sweden)

    Gordo Sheila MC

    2012-09-01

    Full Text Available Abstract Background Black pepper (Piper nigrum L. is one of the most popular spices in the world. It is used in cooking and the preservation of food and even has medicinal properties. Losses in production from disease are a major limitation in the culture of this crop. The major diseases are root rot and foot rot, which are results of root infection by Fusarium solani and Phytophtora capsici, respectively. Understanding the molecular interaction between the pathogens and the host’s root region is important for obtaining resistant cultivars by biotechnological breeding. Genetic and molecular data for this species, though, are limited. In this paper, RNA-Seq technology has been employed, for the first time, to describe the root transcriptome of black pepper. Results The root transcriptome of black pepper was sequenced by the NGS SOLiD platform and assembled using the multiple-k method. Blast2Go and orthoMCL methods were used to annotate 10338 unigenes. The 4472 predicted proteins showed about 52% homology with the Arabidopsis proteome. Two root proteomes identified 615 proteins, which seem to define the plant’s root pattern. Simple-sequence repeats were identified that may be useful in studies of genetic diversity and may have applications in biotechnology and ecology. Conclusions This dataset of 10338 unigenes is crucially important for the biotechnological breeding of black pepper and the ecogenomics of the Magnoliids, a major group of basal angiosperms.

  5. Resistance to black rot in a Spanish Brassica collection.

    OpenAIRE

    Lema Márquez, Margarita; Soengas Fernández, María del Pilar; Velasco Pazos, Pablo; Abilleira Ambroa, Rosaura; Cartea González, María Elena

    2011-01-01

    Xanthomonas campestris pv. campestris (Xcc), causal agent of black rot, is widely distributed around the world in Brassica crops causing severe yield losses. The seedborne bacteria can survive in crop debris or crucifer weeds, introducing in the plant through hydathodes and wounds. While in warm and humid regions Xcc can cause plant dead, in coastal temperate areas it produces necrotic lesions on leaf margin, which decrease the value of the product on fresh market. In northwestern Spain, blac...

  6. Interaction of Rhizoctonia solani and Rhizopus stolonifer Causing Root Rot of Sugar Beet

    Science.gov (United States)

    In recent years, growers in Michigan and other sugar beet production areas of the United States have reported increasing incidence of root rot with little or no crown or foliar symptoms in sugar beet with Rhizoctonia crown and root rot. In addition, Rhizoctonia-resistant beets have been reported wit...

  7. Experimental Sugar Beet Cultivars Evaluated for Resistance Bacterial Root Rot in Idaho, 2008

    Science.gov (United States)

    Bacterial root rot of sugar beet caused by Leuconostoc mesenteroides subsp. dextranicum is a disease problem recently described in the United States. To ameliorate the impact of bacterial root rot on sucrose loss in the field, storage piles, and factories, a study was conducted to identify resistan...

  8. Monitoring cotton root rot progression within a growing season using airborne multispectral imagery

    Science.gov (United States)

    Cotton root rot, caused by the fungus Phymatotrichopsis omnivora, is a serious and destructive disease affecting cotton production in the southwestern United States. Accurate delineation of cotton root rot infections is important for cost-effective management of the disease. The objective of this st...

  9. Comparison of airborne multispectral and hyperspectral imagery for mapping cotton root rot

    Science.gov (United States)

    Cotton root rot, caused by the soilborne fungus, Phymatotrichum omnivorum, is a major cotton disease affecting cotton production in the southwestern and south central U.S. Accurate delineation of root rot infestations is necessary for cost-effective management of the disease. The objective of this s...

  10. Rhizoctonia root rot (Rhizoctoni solani K ü h n of sugar beet in province Vojvodina

    Directory of Open Access Journals (Sweden)

    Stojšin Vera B.

    2006-01-01

    Full Text Available Sugar beet root rot appears regularly each year, but its intensity depends on agro ecological conditions. The predominant causers of root rot in Vojvodina are fungi from Fusarium genus and species Macrophomina phaseolina. Over the last couple of years, more intense occurrence of Rhizoctonia root rot has been observed. Rhizoctonia solani, the causal agent of root rot is present in sugar beet fields. During 2000-2005, on the territory of Vojvodina, the frequency of Rhizoctonia solani in phytopathological isolations from rotted sugar beet roots was between 0,0-18,2%. The intensity of the disease depends on localities, agro ecological conditions and genotypes. Symptoms of Rhizoctonia root rot were registered at some localities in all regions of Vojvodina: Srem, Banat and Bačka. The disease appearance is above all local. It occurs in small patches, on heavy, non-structured soil and on depressed wet parts of plots. Individual diseased plants can be found during July. Brown rot appears on sugar beet roots, with dried tissue on surface, which is present on the tail as well as on the middle part and the head of root. Tissues with described symptoms are deeper regarding the healthy part of root. On vertical root section, the necrotic changes are clearly visible comparing to tissue section without symptoms. The heavily infected tissue forms fissures on roots in most cases. Besides the above-mentioned symptoms on roots, the plant wilting and leaf handle necrosis as well as leaf dying are also observed. When rot spreads to the whole root head, plants quickly die.

  11. Root rot diseases of sugarbeet (Beta vulgaris L as affected by defloliation intensity

    Directory of Open Access Journals (Sweden)

    Karadimos Dimitros A.

    2006-01-01

    Full Text Available The aim of this work was to study the effect of sugar beet re-growth after water stress defoliation on root rots of three cultivars (Europa, Rival Corsica, which were spring sown in Thessaly, central Greece, for two growing seasons (2003-04. At the beginning of July, sugar beets were subjected to water deficit with irrigation withholding. A month later, three defoliation levels (control - C, moderate - MD, severe - SD and irrigation were applied. Thus, sugar beets were forced to re-grow and three harvests (15, 30 and 40 days after defoliation - DAD were conducted. Rotted roots per hectare were counted and pathogens were identified. Data were analyzed as a four-factor randomized complete block design with years, defoliation levels, sampling times and cultivars as main factors. The number of rotted roots was increased with the defoliation level and was significantly higher for SD sugar beets (3748 roots ha–1. No significant differences were found between C and MD treatments (1543 and 2116 roots ha–1, respectively. Rival was the most susceptible cultivar to root rots. Sugar beets were more susceptible to rotting 15 and 40 DAD (2778 and 2998 roots ha–1. The causal agents of root rots were the fungi, Fusarium spp., Rhizopus stolonifer, Macrophomina phaseolina and Rhizoctonia solani.

  12. The Genetic Structure of Phellinus noxius and Dissemination Pattern of Brown Root Rot Disease in Taiwan

    OpenAIRE

    Chung, Chia-Lin; Huang, Shun-Yuan; Huang, Yu-Ching; Tzean, Shean-Shong; Ann, Pao-Jen; Tsai, Jyh-Nong; Yang, Chin-Cheng; Lee, Hsin-Han; Huang, Tzu-Wei; Huang, Hsin-Yu; Chang, Tun-Tschu; Lee, Hui-Lin; Liou, Ruey-Fen

    2015-01-01

    Since the 1990s, brown root rot caused by Phellinus noxius (Corner) Cunningham has become a major tree disease in Taiwan. This fungal pathogen can infect more than 200 hardwood and softwood tree species, causing gradual to fast decline of the trees. For effective control, we must determine how the pathogen is disseminated and how the new infection center of brown root rot is established. We performed Illumina sequencing and de novo assembly of a single basidiospore isolate Daxi42 and obtained...

  13. Colonization Of Exopolysaccharide Producing Paenibacillus Polymyxa On Maize ( Zea Mays L.) Roots For Enhancing Resistance Against Root Rot Disease

    OpenAIRE

    T. Sheela; Usharani

    2013-01-01

    Root rot disease of maize (zae mays L) caused by the highly virulent strain of Aspergillus niger and Fusairum graminearam . The very important plant disease in India and other countries. Maize seeds infected by seed-borne fungi have been reported to produce seed abortion, reduced seed size, seed rot, seed necrosis, seed discoloration, reduce seed germination capacity and physiological alternation of seed. Biological control represents an attractive alternative for the future because for the m...

  14. Survey of root rot diseases of sugar bett in Central Greece

    Directory of Open Access Journals (Sweden)

    Karadimos Dimitros A.

    2006-01-01

    Full Text Available An extensive survey was conducted during the summer and autumn of 2004 in sugar beet fields in the area of Larissa, Thessaly region, with plants showing symptoms of root rot diseases. The aim of the monitoring was to identify the causal agents of root rot diseases. In total, 76 sugar beet fields were surveyed and 5-10 diseased roots were examined from each field. Isolations, carried out on PDA, showed that two main fungal pathogens causing root rot were Rhizoctonia solani and Phytophthora cryptogea. The former was isolated in 46% of the fields and the latter in 38% of the fields. In addition, Rhizopus stolonifer, Fusarium spp., Scerotium rolfsii and Rhizoctonia violacea were isolated in 14%, 7%, 4% and 1% of the fields respectively. In most of the surveyed fields only one pathogen species was isolated and only in a few of them more than one fungal species was identified.

  15. Genome-wide SNP identification and QTL mapping for black rot resistance in cabbage

    OpenAIRE

    Lee, Jonghoon; Izzah, Nur Kholilatul; Jayakodi, Murukarthick; Perumal, Sampath; Joh, Ho Jun; Lee, Hyeon Ju; Lee, Sang-Choon; Park, Jee Young; Yang, Ki-Woung; Nou, Il-Sup; Seo, Joodeok; Yoo, Jaeheung; Suh, Youngdeok; Ahn, Kyounggu; Lee, Ji Hyun

    2015-01-01

    Background Black rot is a destructive bacterial disease causing large yield and quality losses in Brassica oleracea. To detect quantitative trait loci (QTL) for black rot resistance, we performed whole-genome resequencing of two cabbage parental lines and genome-wide SNP identification using the recently published B. oleracea genome sequences as reference. Results Approximately 11.5 Gb of sequencing data was produced from each parental line. Reference genome-guided mapping and SNP calling rev...

  16. Rhizoctonia root rot of lentil caused by Rhizoctonia solani AG 2-1

    Science.gov (United States)

    Lentil root rot symptoms were observed in commercial fields in the US Pacific Northwest during the unusually cool and moist spring weather of 2010. Symptoms included sunken lesions on root and stem with brown discoloration, resembling diseases caused by Rhizoctonia solani. Rhizoctonia solani was i...

  17. Phytophthora Root and Crown Rot on Apples in Bulgaria

    Directory of Open Access Journals (Sweden)

    Mariana Nakova

    2010-01-01

    Full Text Available Phytophthora is a genus of Oomycota responsible for some of the most serious diseases with great economic impact (Judelson and Blanco, 2005. While 54 species were found in the 20th century (Erwin and Ribeiro, 1996 another 51-54 new species have been identified(Brasier, 2008 since the year 2000. They are spread worldwide and have broad range of host plants – fruit trees, citrus, forest and park species. Phytophthora can cause serious damages in orchards and nurseries of apples, cherries, etc. In Bulgaria they have been found first on young apples and cherries (1998-1999 in Plovdiv region (Nakova, 2003. Surveys have been done for discovering disease symptoms in Plovdiv and Kjustendil regions. Isolates have been obtained from infected plant material (roots and stem bases applying baiting bioassay (green apples, variety Granny Smith and/or PARP 10 selective media. Phytophthora strains were identified based on standard morphology methods – types of colonies on PDA, CMA, V 8, type and size of sporangia, oogonia and antheridia, andoospores. Cardial temperatures for their growth were tested on CMA and PDA.For molecular studies, DNA was extracted from mycelium using the DNA extraction kit.DNA was amplified using universal primers ITS 6 and ITS 4. Amplification products concentrations were estimated by comparison with the standard DNA. Sequencing was done at the Scottish Crop Research Institute (SCRI, Dundee, Scotland. Phytophthora root and crown rot symptoms first appear in early spring. Infected trees show bud break delay, have small chlorotic leaves, and branches die all of a sudden. Later symptoms are found in August-September. Leaves of the infected trees show reddish discoloration and drop down. Both symptoms are connected with lesions (wet, necrotic in appearance at stem bases of the trees.Disease spread was 2-3% in most gardens, only in an apple orchard in Bjaga (Plovdiv region it was up to 8-10%. Morphologically, the isolates acquired from

  18. Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt.

    Science.gov (United States)

    Hassan, Naglaa; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-03-01

    Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt. PMID:24808737

  19. Root Rot of Balloon Flower (Platycodon grandiflorum) Caused by Fusarium solani and Fusarium oxysporum.

    Science.gov (United States)

    Jeon, Chi Sung; Kim, Gyoung Hee; Son, Kyeong In; Hur, Jae-Seoun; Jeon, Kwon-Seok; Yoon, Jun-Hyuck; Koh, Young Jin

    2013-12-01

    Balloon flower (Platycodon grandiflorum) is a kind of mountain herbs whose roots have restorative properties and the cultivating acreage of balloon flower has been steadily increasing in Korea. More frequent rain and high amount of rainfalls as a result of climate changes predisposed balloon flower to the outbreaks of root rot at high-density cultivation area in recent years. Root crowns were usually discolored into brown to blackish brown at first and the infected plants showed slight wilting symptom at early infection stage. Severely infected roots were entirely rotted and whole plants eventually died at late infection stage. The overall disease severities of root rot of balloon flower were quite variable according to the surveyed fields in Jeonnam, Gyeongnam and Jeju Provinces, which ranged from 0.1% to 40%. The root rot occurred more severely at the paddy or clay soils than the sandy soils and their severities were much higher at lowland than upland in the same localty. The disease increased with aging of the balloon flower. The causal fungi were identified as Fusarium solani and F. oxysporum on the basis of their mycological characteristics. The optimum temperature ranges of their mycelial growths was found to be 24°C. The pathogenic characters of F. solani and F. oxysporum treated by artificial wounding inoculation on healthy roots of balloon flower revealed that F. solani was more virulent than F. oxysporum. This study identified the causal agents of root rot of balloon flower as Fusarium solani and F. oxysporum, probably for the first time. PMID:25288973

  20. Rhizoctonia crown and root rot resistance evaluation of Beta PIs in Fort Collins, CO, 2015

    Science.gov (United States)

    Thirty beet accessions of either cultivated beet or sea beet (Beta vulgaris subsp. vulgaris or Beta vulgaris subsp. maritima (L.) Arcang) from the Beta collection of the USDA-Agricultural Research Service National Plant Germplasm System were screened for resistance to Rhizoctonia crown and root rot ...

  1. Creating prescription maps from historical imagery for site-specific management of cotton root rot

    Science.gov (United States)

    Cotton root rot, caused by the soilborne fungus Phymatotrichopsis omnivore, is a severe plant disease that has affected cotton production for over a century. Recent research found that a commercial fungicide, Topguard (flutriafol), was able to control this disease. As a result, Topguard Terra Fungic...

  2. Controlled release fungicide, soil amendments and biofumigation effects on cotton root rot suppression

    Science.gov (United States)

    The cotton root rot pathogen (Phymatotrichopsis ominora) causes major losses in cotton produced in the Southwest. Granular controlled release formulations (CRF) of the fungicide, Propiconazole, developed to be soil applied at planting were studied at 1.0 and 3.0 lb a.i./ac. applications and with tw...

  3. Change detection of cotton root rot infection over a 10-year interval using airborne multispectral imagery

    Science.gov (United States)

    Cotton root rot is a very serious and destructive disease of cotton grown in the southwestern and south central United States. Accurate information regarding the spatial and temporal infections of the disease within fields is important for effective management and control of the disease. The objecti...

  4. Development of Phytophthora root rot-resistant avocado rootstocks for the Caribbean.

    Science.gov (United States)

    Phytophtora root rot (PRR), caused by Phytopthora cinnamoni Rands, poses the greatest limitation to avocado production worldwide. Through a collaborative effort between researchers at the USDA-ARS facility in Miami and the University of Florida in Homestead, PRR-resistant avocado rootstocks are bein...

  5. Basal Root Rot, a new Disease of Teak (Tectona grandis) in Malaysia caused by Phellinus noxius

    OpenAIRE

    Mohd Farid, A.; S. S. Lee; Maziah, Z.; Rosli, H.; Norwati, M.

    2005-01-01

    Basal root rot of teak was first reported from Sabak Bernam, Selangor making this the first report of the disease on teak in Peninsular Malaysia. The fungus found associated with the disease was Phellinus noxious. The disease aggressively killed its host irrespective of the host health status. Bark depression at the root collar which was visible from a distance was the characteristic symptom and the main indicator in identifying the disease in the plantation since above ground symptoms of the...

  6. Mechanisms of biological control of Fusarium root and stem rot of greenhouse cucumber by Gliocladium catenulatum

    OpenAIRE

    Chatterton, Syama Gauri Dasi

    2010-01-01

    Gliocladium catenulatum strain J1446 (formulated as Prestop WP, Verdera Oy) is a biological control agent of Fusarium root and stem rot caused by Fusarium oxysporum f. sp. radicis-cucumerinum on greenhouse cucumber plants. The mechanisms involved in biocontrol efficacy are currently unknown. Following transformation of G. catenulatum with the ß-glucuronidase (uidA) gene, blue-stained mycelia could be seen growing on the surface and within epidermal and cortical cells of roots, stems and shoot...

  7. Phytophthora root and stem rot – new disease of Ilex aquifolium "Myrtifolia” in Poland

    Directory of Open Access Journals (Sweden)

    Leszek B. Orlikowski

    2014-08-01

    Full Text Available Phytophthora cinnamomi was often isolated from rotted roots and stems of English holly "Myrtifolia" together with Alternaria alternata, Cylindrocarpon destructanss, Fusarium avenaceum and other fungal species. Inoculation of leaf blades and stem parts of 4 species and 12 holly cultivars with P. cinnamomi showed the spread of rot symptoms on the most of them. On Ilex crenata tissues necrosis did not develop or spread slowly. Isolation of P. cinnamomi only from one holly cultivar in surveyed nursery indicate on transmission of the pathogen with imported young plants.

  8. New record of Phytophthora root and stem rot of Lavandula angustifolia

    Directory of Open Access Journals (Sweden)

    Leszek B. Orlikowski

    2013-12-01

    Full Text Available Phytophthora cinnamomi was isolated from rotted root and stem parts of lavender as well as from soil taken from containers with diseased plants. Additionally Botrytis cinerea, Fusarium spp. and Sclerotinia sclerotiorum were often isolated from diseased tissues. P. cinnamomi colonised leaves and stem parts of 4 lavender species in laboratory trials and caused stem rot of plants in greenhouse experiments. Cardinal temperature for in vitro growth were about 7,5 and 32°C with optimum 25-27,5°C. The species colonised stem tissues at temperature ranged from 10° to 32°C.

  9. Fusarium species from the cassava root rot complex in west Africa.

    Science.gov (United States)

    Bandyopadhyay, Ranajit; Mwangi, Maina; Aigbe, Sylvester O; Leslie, John F

    2006-06-01

    ABSTRACT Fusarium species are a significant component of the set of fungi associated with cassava root rot. Yield losses due to root rot average 0.5 to 1 ton/ha but losses >3 ton/ha, an equivalent of 15 to 20% yield, often occur. This paper reviews previous work on cassava root rot and summarizes a few recent studies on Fusarium species associated with the disease. Our studies in Cameroon showed that 30% of rotted tubers were infected by Fusarium spp. 12 months after planting and represented 25% of all the fungal isolates recovered. Other commonly recovered fungi were Botryodiplodia theobromae and Armillaria spp. Numerous and diverse species of Fusarium were associated with rotted cassava roots in Nigeria and Cameroon. At least 13 distinct amplified fragment length polymorphism (AFLP) groups of Fusarium were distinguishable, each group probably a distinct species, and many of them might represent previously undescribed Fusarium species. The two largest of the AFLP groups correspond to F. oxysporum and F. solani species complex. The distribution of Fusarium spp. varied among countries and among locations within a country, suggesting that germ plasm resistant at one location may not be resistant at another. Fusarium spp. also cause seedling blight of cassava and can be recovered from the stems of infected plants up to 1 m above the ground. Therefore, the pathogen can spread with stems cut as planting material. Fusarium spp. also can colonize Chromolaena odorata, the dominant weed in short fallows, which could further complicate management efforts by serving as an alternative host for strains that colonize cassava. PMID:18943189

  10. A DNA based method to detect the grapevine root-rotting fungus Roesleria subterranea in soil and root samples

    OpenAIRE

    Neuhauser, Sigrid; Huber, Lars; Kirchmair, Martin

    2009-01-01

    Roesleria subterranea causes root rot in grapevine and fruit trees. The fungus has long been underestimated as a weak parasite, but during the last years it has been reported to cause severe damages in German vineyards. Direct, observation-based detection of the parasite is time consuming and destructive, as large parts of the rootstocks have to be uprooted and screened for the tiny, stipitate, hypogeous ascomata of R. subterranea. To facilitate rapid detection in vineyards, protocols to extr...

  11. Effects of Fungicides, Essential Oils and Gamma Irradiated Bioagents on Chickpea Root Rot Caused by Sclerotium rolfsii

    International Nuclear Information System (INIS)

    Sclerotium rolfsii (S. rolfsii) causes root rot disease in several crops including Cicer arietinum (chickpea) that results in low yield. In vitro experiments on fungicides, vitavax and monceren T, and essential oils, clove and mint oils, were conducted to control root rot disease of chickpea caused by S. rolfsii. The treatments resulted in 80 % suppression of root rot disease. Gliocladium virens (G. virens) and Gliocladium deliquescens (G. deliquescens) were effective as biocontrol agents against S. rolfsii. The results showed that these treatments greatly reduced the root rot disease in chickpea. In this study, the effect of gamma irradiation at doses 0, 0.25, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 kGy on the pathogenecity of G. virens and G. deliquescens against S. rolfsii were investigated. The results revealed that gamma irradiation increased the pathogenecity of G. virens and G. deliquescens against S. rolfsii

  12. Wide Variation in Virulence and Genetic Diversity of Binucleate Rhizoctonia Isolates Associated with Root Rot of Strawberry in Western Australia

    OpenAIRE

    Xiangling Fang; Finnegan, Patrick M.; Barbetti, Martin J.

    2013-01-01

    Strawberry (Fragaria×ananassa) is one of the most important berry crops in the world. Root rot of strawberry caused by Rhizoctonia spp. is a serious threat to commercial strawberry production worldwide. However, there is no information on the genetic diversity and phylogenetic status of Rhizoctonia spp. associated with root rot of strawberry in Australia. To address this, a total of 96 Rhizoctonia spp. isolates recovered from diseased strawberry plants in Western Australia were characterized ...

  13. MANAGEMENT OF ROOT ROT DISEASE [MACROPHOMINA PHASEOLINA (TASSI. GOID] OF CHICKPEA THROUGH BOTANICALS AND OIL CAKES

    Directory of Open Access Journals (Sweden)

    S. S. KANSARA

    2013-01-01

    Full Text Available Occurrence of root rot disease in chickpea has become a major constraint for cultivation of chickpea. Consideringthe fact, below investigation was carried out for this pathological problem. The efficacy of various botanicals andoil cakes were evaluated against Macrophomina phaseolina (Tassi. Goid causing dry root rot of chickpea. Thephyto extracts of thirteen plant species were evaluated in vitro by poisoned food technique against M. phaseolina.The extract of garlic cloves (Allium sativum L. was proved excellent with maximum inhibiting (73 % mycelialgrowth and sclerotial formation followed by rhizome extract of turmeric (Curcuma longa L (63.98 %. The fourorganic extracts were tested against M. phaseolina by poisoned food technique in vitro. Significantly least growthof mycelium and maximum mycelium inhibition was recorded in extracts of neem cake (59.40 % followed byfarm yard manure (42.56 %. Next best in order of merit were castor cake and mustard cake.

  14. Recombinant inbred line differential identifies race-specific resistance to phytophthora root rot in Capsicum annuum.

    Science.gov (United States)

    Sy, O; Steiner, R; Bosland, P W

    2008-08-01

    A differential series is the normal method for identification of races within a plant pathogen and a host interaction. A host differential is extremely useful for phytopathological as well as breeding purposes. A set of recombinant inbred lines (RILs) were developed and characterized for race differentiation of Phytophthora root rot caused by Phytophthora capsici. The highly resistant Capsicum annuum accession Criollo de Morelos-334 was hybridized to a susceptible cultivar, Early Jalapeno, to generate the RIL population. The host differential characterized 17 isolates of P. capsici into 13 races. The establishment of a stable host differential for the P. capsici and C. annuum interaction will assist researchers in understanding the complex inheritance of resistance to Phytophthora root rot and to develop resistant cultivars. PMID:18943204

  15. The Use of Antioxidants to Control Root Rot and Wilt Diseases of Pepper

    Directory of Open Access Journals (Sweden)

    Montaser Fawzy ABDEL-MONAIM

    2010-06-01

    Full Text Available Ten isolates of Fusarium spp were isolated from pepper plants collected from different locations in New Valley Governorate, Egypt. Fusarium solani isolate FP2 and F. oxysporum isolate FP4 were highly pathogenic isolates but the other isolates moderate or less pathogenic to pepper plants (cv. Anaheim-M. The four antioxidant compounds (coumaric acid, citric acid, propylgalate and salicylic acid each at 100 and 200 ppm were evaluated for their in vitro and in vivo agonist to Fusarium pathogenic isolates caused root rot and wilt diseases in pepper plants. All tested antioxidant compounds reduced damping-off, root rot/wilt and area under root rot/wilt progress curve when used as seed soaking, seedling soaking, and soil drench especially at 200 ppm under greenhouse and field conditions compared with untreated plants. All chemicals increased fresh and dry weight of seedling grown in soil drenching or seed treatment with any antioxidants. At the same time, all tested chemicals significantly increase plant growth parameters i.e plant length, plant branching, and total yield per plant in case of seedling soaking or soil drench. In general, propylgalate at 200 ppm was more efficient in reducing infection with damping-off, root rot and wilt diseases as well as increasing the seedling fresh weight, dry weight, plant length, plant branching, number of pod plant-1 and pod yield plant-1. On the other hand, all tested antioxidants had less or no effect on mycelial dry weight and mycelial leaner growth. On the contrary, all chemicals much reduced spore formation in both Fusarium species at 100 or 200 ppm and the inhibitory effect of antioxidants increased with increasing their concentrations.

  16. Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt

    OpenAIRE

    Hassan, Naglaa; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-01-01

    Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated wit...

  17. Low Water Availability Enhancing Soil Receptivity to Fusarium Pathogen: Case of Root Rot on Mulberry

    OpenAIRE

    Rosmana, Ade

    2014-01-01

    In mulberry, Fusarium root rot (FRR) causes considerable damage with the symptoms being the most visible in the dry season. A study was conducted using mulberry plants grown in pots to evaluate the effect of soil water availability on the Fusarium disease incidence and the pathogen and other microbe populations in the soil. Treatments consisted of low, medium, and high soil water availabilities in the range between the permanent wilting point and the field capacity. Anoth...

  18. Leuconostoc spp. Associated with Root Rot in Sugar Beet and Their Interaction with Rhizoctonia solani.

    Science.gov (United States)

    Strausbaugh, Carl A

    2016-05-01

    Rhizoctonia root and crown rot is an important disease problem in sugar beet caused by Rhizoctonia solani and also shown to be associated with Leuconostoc spp. Initial Leuconostoc studies were conducted with only a few isolates and the relationship of Leuconostoc with R. solani is poorly understood; therefore, a more thorough investigation was conducted. In total, 203 Leuconostoc isolates were collected from recently harvested sugar beet roots in southern Idaho and southeastern Oregon during 2010 and 2012: 88 and 85% Leuconostoc mesenteroides, 6 and 15% L. pseudomesenteroides, 2 and 0% L. kimchi, and 4 and 0% unrecognized Leuconostoc spp., respectively. Based on 16S ribosomal RNA sequencing, haplotype 11 (L. mesenteroides isolates) comprised 68 to 70% of the isolates in both years. In pathogenicity field studies with commercial sugar beet 'B-7', all Leuconostoc isolates caused more rot (P solani than when inoculated alone in both years. Also, 46 of the 52 combination treatments over the 2 years had significantly more rot (P solani are present in sugar beet roots. PMID:26735061

  19. Control of Root Rot and Wilt Diseases of Roselle under Field Conditions.

    Science.gov (United States)

    Hassan, Naglaa; Elsharkawy, Mohsen Mohamed; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-12-01

    Roselle (Hibiscus sabdariffa L.) is one of the most important medicinal crops in many parts of the world. In this study, the effects of microelements, antioxidants, and bioagents on Fusarium oxysporum, F. solani, and Macrophomina phaseolina, the causal pathogens of root rot and wilt diseases in roselle, were examined under field conditions. Preliminary studies were carried out in vitro in order to select the most effective members to be used in field control trials. Our results showed that microelements (copper and manganese), antioxidants (salicylic acid, ascorbic acid, and EDTA), a fungicide (Dithane M45) and biological control agents (Trichoderma harzianum and Bacillus subtilis) were significantly reduced the linear growth of the causal pathogens. Additionally, application of the previous microelements, antioxidants, a fungicide and biological control agents significantly reduced disease incidence of root rot and wilt diseases under field conditions. Copper, salicylic acid, and T. harzianum showed the best results in this respect. In conclusion, microelements, antioxidants, and biocontrol agents could be used as alternative strategies to fungicides for controlling root rot and wilt diseases in roselle. PMID:25606010

  20. Root and crown rot and wilt of tomatoes caused by fungal diseases in Ankara province.

    OpenAIRE

    Ozan, S.; Maden, S.

    2009-01-01

    This study was conducted in Ayaş, Beypazarı and Nallıhan districts of Ankara province during May-November 2003-2004 in order to detect fungal pathogens of tomato, and to find out the incidence, prevalence and occurrence times of these pathogens. It is detected that wilt and root rot pathogens causes important yield losses in tomato fields in Ankara. The incidences of the fungi isolated roots and crowns were 17.2 %, 0.96 %, 0.32 %, 0.91 %, 2.95 %,% 0.52 for Pyrenochaeta lycopersici, Fusa...

  1. The Genetic Structure of Phellinus noxius and Dissemination Pattern of Brown Root Rot Disease in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chia-Lin Chung

    Full Text Available Since the 1990s, brown root rot caused by Phellinus noxius (Corner Cunningham has become a major tree disease in Taiwan. This fungal pathogen can infect more than 200 hardwood and softwood tree species, causing gradual to fast decline of the trees. For effective control, we must determine how the pathogen is disseminated and how the new infection center of brown root rot is established. We performed Illumina sequencing and de novo assembly of a single basidiospore isolate Daxi42 and obtained a draft genome of ~40 Mb. By comparing the 12,217 simple sequence repeat (SSR regions in Daxi42 with the low-coverage Illumina sequencing data for four additional P. noxius isolates, we identified 154 SSR regions with potential polymorphisms. A set of 13 polymorphic SSR markers were then developed and used to analyze 329 P. noxius isolates collected from 73 tree species from urban/agricultural areas in 14 cities/counties all around Taiwan from 1989 to 2012. The results revealed a high proportion (~98% of distinct multilocus genotypes (MLGs and that none of the 329 isolates were genome-wide homozygous, which supports a possible predominant outcrossing reproductive mode in P. noxius. The diverse MLGs exist as discrete patches, so brown root rot was most likely caused by multiple clones rather than a single predominant strain. The isolates collected from diseased trees near each other tend to have similar genotype(s, which indicates that P. noxius may spread to adjacent trees via root-to-root contact. Analyses based on Bayesian clustering, FST statistics, analysis of molecular variance, and isolation by distance all suggest a low degree of population differentiation and little to no barrier to gene flow throughout the P. noxius population in Taiwan. We discuss the involvement of basidiospore dispersal in disease dissemination.

  2. The Genetic Structure of Phellinus noxius and Dissemination Pattern of Brown Root Rot Disease in Taiwan.

    Science.gov (United States)

    Chung, Chia-Lin; Huang, Shun-Yuan; Huang, Yu-Ching; Tzean, Shean-Shong; Ann, Pao-Jen; Tsai, Jyh-Nong; Yang, Chin-Cheng; Lee, Hsin-Han; Huang, Tzu-Wei; Huang, Hsin-Yu; Chang, Tun-Tschu; Lee, Hui-Lin; Liou, Ruey-Fen

    2015-01-01

    Since the 1990s, brown root rot caused by Phellinus noxius (Corner) Cunningham has become a major tree disease in Taiwan. This fungal pathogen can infect more than 200 hardwood and softwood tree species, causing gradual to fast decline of the trees. For effective control, we must determine how the pathogen is disseminated and how the new infection center of brown root rot is established. We performed Illumina sequencing and de novo assembly of a single basidiospore isolate Daxi42 and obtained a draft genome of ~40 Mb. By comparing the 12,217 simple sequence repeat (SSR) regions in Daxi42 with the low-coverage Illumina sequencing data for four additional P. noxius isolates, we identified 154 SSR regions with potential polymorphisms. A set of 13 polymorphic SSR markers were then developed and used to analyze 329 P. noxius isolates collected from 73 tree species from urban/agricultural areas in 14 cities/counties all around Taiwan from 1989 to 2012. The results revealed a high proportion (~98%) of distinct multilocus genotypes (MLGs) and that none of the 329 isolates were genome-wide homozygous, which supports a possible predominant outcrossing reproductive mode in P. noxius. The diverse MLGs exist as discrete patches, so brown root rot was most likely caused by multiple clones rather than a single predominant strain. The isolates collected from diseased trees near each other tend to have similar genotype(s), which indicates that P. noxius may spread to adjacent trees via root-to-root contact. Analyses based on Bayesian clustering, FST statistics, analysis of molecular variance, and isolation by distance all suggest a low degree of population differentiation and little to no barrier to gene flow throughout the P. noxius population in Taiwan. We discuss the involvement of basidiospore dispersal in disease dissemination. PMID:26485142

  3. Control of sooty blotch and black rot of apple through removal of fruit mummies

    OpenAIRE

    Beer Margarita; Brockamp Leona; Weber Roland W.S.

    2015-01-01

    Several popular apple cultivars retain their aborted fruits as mummies on the tree. In laboratory conditions, overwintered fruit mummies collected from a Northern German apple orchard under organic management released inoculum, which caused black rot due to Diplodia seriata and sooty blotch due to Peltaster cerophilus on ripe apples. In a field trial conducted over four years in another organic orchard, the manual removal of fruit mummies in winter and again in late June of each year signific...

  4. Basal Root Rot, a new Disease of Teak (Tectona grandis in Malaysia caused by Phellinus noxius

    Directory of Open Access Journals (Sweden)

    Mohd Farid, A.

    2005-01-01

    Full Text Available Basal root rot of teak was first reported from Sabak Bernam, Selangor making this the first report of the disease on teak in Peninsular Malaysia. The fungus found associated with the disease was Phellinus noxious. The disease aggressively killed its host irrespective of the host health status. Bark depression at the root collar which was visible from a distance was the characteristic symptom and the main indicator in identifying the disease in the plantation since above ground symptoms of the canopy could not be differentiated from crowns of healthy trees. However, although above ground symptoms were not easily discernible, the disease was already advanced and the trees mostly beyond treatment; 3.4 % of the trees in the plantation were affected and the disease occurred both on solitary trees and in patches. Below ground, infected trees had rotted root systems, mainly below and around the collar region with brown discolored wood and irregular golden-brown honeycomb-like pockets of fungal hyphae in the wood. Pathogenicity tests showed that the fungus produced symptoms similar to those observed in the plantation and killed two year-old teak plants. The disease killed all the inoculated hosts within three months, irrespective of wounded or unwounded treatments.

  5. Use of homeopathic drugs in combination with fertilizers for the control of root rot fungi

    International Nuclear Information System (INIS)

    This study was conducted to evaluate the fungicidal effectiveness of homeopathic drugs in combination with fertilizers on the growth production and controlling of root rot fungi. Seeds treated with homeopathic drugs in addition of phosphorous and nitrogen fertilizers as soil amendment showed significant inhibitory effect on fungal growth as well as improved the plant growth. Remarkable control of root infecting fungi was shown by the seeds treated with Thuja occidentalis and Arnica montana at rate of 75 percentage v/v concentration and soil amended with urea at rate of 0.1 percentage w/w but greater increased in plant growth was observed by urea at rate of 0.01 percentage in the tested plants viz. mung bean, mash bean, sunflower and okra. Whereas, when A. montana and T. occidentalis at rate of 75 percentage v/v concentration along with the addition of DAP at rate of 0.01 and 0.1 percentage w/w respectively showed maximum suppression of Fusarium spp, R. solani and M. phaseolina and enhanced the plant height and weight followed by A. montana and T. occidentalis at rate of 50 percentage v/v concentration respectively showed a maximum control of root rot fungi and also strengthened the crop plant for better growth. (author)

  6. The effect of mangroves amendments to soil on root rot and root knot of potato (Solanum tuberosum L.

    Directory of Open Access Journals (Sweden)

    Marium Tariq

    2012-12-01

    Full Text Available Leaves, stem and pneumatophore of Avicennia marina and leaves and stem of Rhizophora mucronata were used as the organic amendments at 0.1, 1 and 5% concentrations in the control of root rot fungi like (Fusarium spp., Rhizoctonia solani and Macrophomina phasoelina and root knot nematode Meloidogyne javanica on potato. In pot experiments, germination of seeds, shoot length, shoot weight, root length, root weight and number of knots were significantly increased when plant parts like leaves, stem and pneumatophore of A. marina and R. mucronata were used at 1 and 5% concentrations. There was a complete suppression in infection of R. solani and M. phaseolina when A. marina and R. mucronata were used at 5% concentration on potato. Maximum inhibition of knots of M. javanica was observed when powder made from mangrove plant parts was used at 1 and 5% concentrations. Powder from all plant parts, like leaves, stem and pneumatophore, was effective in suppression of root infecting fungi and root knot nematode.

  7. Irradiation seed treatment reduces scald, common root rot and increases phosphorus absorption of barley

    International Nuclear Information System (INIS)

    The effect of low doses of gamma irradiation on severity of barley to scald and common root rot diseases, and phosphorus absorption was studied seeds were exposed to doses of 0, 10, 15, 20, 30, 40 and 50 Gy. A stimulatory effect was observed at irradiation doses of 30 and 40 Gy, which decreased the severity of barley to scald by 34% and 31% respectively. On the other hand, doses 20 and 30 Gy decreased the severity to CRR by 54% and 49% respectively, whereas, phosphorus absorption was significantly increased at doses of 15 and 20 Gy

  8. IMPROVMENT BIOCONTROL OF DAMPING-OFF AND ROOT ROT/WILT OF FABA BEAN BY SALICYLIC ACID AND HYDROGEN PEROXIDE

    OpenAIRE

    Montaser F. Abdel-Monaim

    2013-01-01

    Rhizoctonia solani, Fusarium solani, F. oxysporum and Macrophomina phaseolina were found to be associated with root rot and wilt symptoms of faba bean plants collected from different fields in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenici...

  9. Diplodia seriata, cause of black fruit rot in organically grown apples in Holland, Belgium and Northern Germany

    OpenAIRE

    Trapman, Marc; Maxin, Peter; Weber, Roland W. S.

    2008-01-01

    A fruit rot resembling Gloeosporium infections but appearing on fruits prior to harvest was noticed in organic apple orchards in Holland, Belgium and Northern Germany in 2007. Infections were most commonly observed on ‘Elstar’, but other cultivars were also affected. Fruit colonisation progressed in two steps, whereby a latent stage of sunken black lesions in immature fruits gave rise to a rapidly spreading firm brown rot upon fruit ripening. Isolation experiments from both sta...

  10. Biological control of Rhizoctonia root rot on bean by phenazine- and cyclic lipopeptide-producing Pseudomonas CMR12a

    Science.gov (United States)

    Pseudomonas CMR12a was previously selected as an efficient biocontrol strain producing phenazines and cyclic lipopeptides (CLPs). In this study, biocontrol capacity of Pseudomonas CMR12a against Rhizoctonia root rot of bean and the involvement of phenazines and CLPs in this ability were tested. Two ...

  11. Gene-for-gene relationships between strawberry and the causal agent of red stele root rot, Phytophthora fragariae var. fragariae.

    NARCIS (Netherlands)

    Weg, van de W.E.

    1997-01-01

    Red stele (red core) root rot is the major soil-borne disease of strawberries (Fragaria spp.) in many areas with cool, moist soil conditions. It is caused by the soil-borne fungus Phytophthora fragariae var. fragariae. Red stele is a quarantine disease in Europe with a zero tolerance for commercial

  12. The prevalence of different strains of Rhizoctonia solani associated with Rhizoctonia crown and root rot symptoms in Ontario sugarbeet fields

    Science.gov (United States)

    Rhizoctonia crown and root rot (RCRR) [Rhizoctonia solani Kühn] is an important disease of sugarbeets in southwestern Ontario, Canada. A survey of commercial sugarbeet fields was completed in 2010 and 2011 to determine the range of R. solani anastomosis groups (AGs) and inter-specific groups (ISGs) ...

  13. Isolates of Rhizoctonia solani can produce both web blight and root rot symptoms in common bean (Phaseolus vulgaris L.)

    Science.gov (United States)

    Rhizoctonia solani Kühn (Rs) is an important pathogen in the tropics, causing web blight (WB), and a widespread soil-borne root rot (RR) pathogen of common bean (Phaseolus vulgaris L.) worldwide. This pathogen is a species complex classified into 14 anastomosis groups (AG). Some AGs have been report...

  14. The effect of temperature on Rhizoctonia disease development and fungicide efficacy in controlling Rhizoctonia root rot on sugarbeet

    Science.gov (United States)

    Rhizoctonia solani AG 2-2 is the causal agent of Rhizoctonia root and crown rot in sugarbeet. This disease has recently been increasing in occurrence and severity in sugarbeet production areas in the Red River Valley of Minnesota and North Dakota. Since the intraspecific groups AG 2-2 IIIB and AG 2-...

  15. Using airborne multispectral imagery to monitor cotton root rot progression in fungicide-treated and non-treated cotton fields

    Science.gov (United States)

    Cotton root rot has affected cotton production in the southwestern and south central U.S for over 100 years. A fungicide, flutriafol, has shown considerable promise for controlling this disease in field studies in the last few years. With the temporary authorization for use of the fungicide to contr...

  16. ROOT ROT OF CHILLI INCITED BY Sclerotium rolfsii Sacc. AND ITS MANAGEMENT- A REVIEW

    Directory of Open Access Journals (Sweden)

    V.Madhuri

    2014-02-01

    Full Text Available Chilli (Capsicum annum L. belongs to the family solanaceae is mainly cultivated for its vegetable green fruits and dry chilli as the spice. It is believed to be originated from South America. It is a rich source of Vitamin C, A and B. Chilli is valued for pungency which is imparted by an alkaloid, Capsaicin and the red pigments (Capsanthin, Capsorubin and Capxanthin. Chillies are widely used as spice, condiment, culinary, supplement, medicine, vegetable and are ornamental plants too. It is an important food flavouring ingredientfor flavouring many vegetarian and non-vegetarian food products. In view of its multifarious uses, the demand for chillies has been on the increase world over. In India it is an important cash crop, which is grown for the domestic market and for export. In India, chillies are grown in almost all states of the country and the major growing states in terms of production are Andhra Pradesh, Karnataka, Orissa, Maharashtra, West Bengal, Rajasthan and Tamil Nadu. There are several varieties of chilli cultivated in India. The most popular among these are, Sannam, LC334, Byadagi, Wonderhot, Jwala etc. The crop suffers from many diseases like damping off, anthracnose or fruit rot or dieback, wilt, leaf spots and powdery mildew. Among the fungal diseases, root rot of chilli caused by Sclerotium rolfsii has attained the economic importance. In recent years, this disease is causing the economic losses in chillies crop (Kalmesh and Gurjar 2001.

  17. A Simple Method for Assessing Severity of Common Root Rot on Barley

    Directory of Open Access Journals (Sweden)

    Mohammad Imad Eddin Arabi

    2013-12-01

    Full Text Available Common root rot caused by Cochliobolus sativus is a serious disease of barley. A simple and reliable method for assessing this disease would enhance our capacity in identifying resistance sources and developing resistant barley cultivars. In searching for such a method, a conidial suspension of C. sativus was dropped onto sterilized elongated subcrown internodes and incubated in sandwich filter paper using polyethylene transparent envelopes. Initial disease symptoms were easily detected after 48h of inoculation. Highly significant correlation coefficients were found in each experiment (A, B and C between sandwich filter paper and seedling assays, indicating that this testing procedure was reliable. The method presented facilitates a rapid pre-selection under uniform conditions which is of importance from a breeder’s point of view.

  18. Improved horticultural practices against leaf wilting, root rot and nutrient uptake in mango (mangiferaindica l.)

    International Nuclear Information System (INIS)

    Poor plant health condition due to various known biotic and abiotic stresses; becoming a disaster in each mango growing country of the world including Pakistan. On the basis of previous researches on the identification of pathogen and several abiotic factors; Soil drenching and foliar spray of various concentrations of Topsin M (TMIC), Aliette (ATP) and Ridomil Gold (ACE) in combination with CuSO/sub 4/(Copper sulphate) was done on mango plants of cv. S.B. (Samar Bahist) Chaunsa showing wilting of leaves and shoots. Foliar application of micro-nutrients (Fe, B and Zn) (Iron, Boron and Zinc) was also practiced to improve general health of experimental plants Month-wise emergence of flushes was significantly higher in all treated plants compared with control. Percentage of wilted leaves and root rot in plants, which received drenching and foliar treatments, was significantly reduced (50%) compared with untreated plants. Nitrogen, phosphorus and potassium (N, P and K) levels in leaves were significantly improved in treated plants compared with control. Sigmoid relatioship was observed between fungicides and copper sulphate concentrations and uptake of N, P and K in treated plants. Application of 250g ATP fungicide by foliar spray plus 125g by soil drench, each along with 50g CuSO/sub 4/proved to be the best against leaf wilting and it improved the N and P level in leaves. While, application of 250g TMIC by foliar spray and 125g by soil drench, each with 50g CuSO/sub 4/, was found to be the best to reduce the spread of root rot in experimental plants. Preliminary spray of TMIC along with Copper sulphate is effective to improve plant health of mango cv. S.B. Chounsa. (author)

  19. Development of a DNA Microarray-Based Assay for the Detection of Sugar Beet Root Rot Pathogens.

    Science.gov (United States)

    Liebe, Sebastian; Christ, Daniela S; Ehricht, Ralf; Varrelmann, Mark

    2016-01-01

    Sugar beet root rot diseases that occur during the cropping season or in storage are accompanied by high yield losses and a severe reduction of processing quality. The vast diversity of microorganism species involved in rot development requires molecular tools allowing simultaneous identification of many different targets. Therefore, a new microarray technology (ArrayTube) was applied in this study to improve diagnosis of sugar beet root rot diseases. Based on three marker genes (internal transcribed spacer, translation elongation factor 1 alpha, and 16S ribosomal DNA), 42 well-performing probes enabled the identification of prevalent field pathogens (e.g., Aphanomyces cochlioides), storage pathogens (e.g., Botrytis cinerea), and ubiquitous spoilage fungi (e.g., Penicillium expansum). All probes were proven for specificity with pure cultures from 73 microorganism species as well as for in planta detection of their target species using inoculated sugar beet tissue. Microarray-based identification of root rot pathogens in diseased field beets was successfully confirmed by classical detection methods. The high discriminatory potential was proven by Fusarium species differentiation based on a single nucleotide polymorphism. The results demonstrate that the ArrayTube constitute an innovative tool allowing a rapid and reliable detection of plant pathogens particularly when multiple microorganism species are present. PMID:26524545

  20. A DNA based method to detect the grapevine root-rotting fungus Roesleria subterranea in soil and root samples.

    Science.gov (United States)

    Neuhauser, Sigrid; Huber, Lars; Kirchmair, Martin

    2009-08-01

    Roesleria subterranea causes root rot in grapevine and fruit trees. The fungus has long been underestimated as a weak parasite, but during the last years it has been reported to cause severe damages in German vineyards. Direct, observation-based detection of the parasite is time consuming and destructive, as large parts of the rootstocks have to be uprooted and screened for the tiny, stipitate, hypogeous ascomata of R. subterranea. To facilitate rapid detection in vineyards, protocols to extract DNA from soil samples and grapevine roots, and R.-subterranea-specific PCR primers were designed. Twelve DNA-extraction protocols for soil samples were tested in small-scale experiments, and selected parameters were optimised. A protocol based on ball-mill homogenization, DNA extraction with SDS, skim milk, chloroform, and isopropanol, and subsequent purification of the raw extracts with PVPP-spin-columns was most effective. This DNA extraction protocol was found to be suitable for a wide range of soil-types including clay, loam and humic-rich soils. For DNA extraction from grapevine roots a CTAB-based protocol was more reliable for various grapevine rootstock varieties. Roesleria-subterranea-specific primers for the ITS1-5.8S-ITS2 rDNA-region were developed and tested for their specificity to DNA extracts from eleven R. subterranea strains isolated from grapevine and fruit trees. No cross reactions were detected with DNA extracts from 44 different species of fungi isolated from vineyard soils. The sensitivity of the species-specific primers in combination with the DNA extraction method for soil was high: as little as 100 fg μl(-1)R.-subterranea-DNA was sufficient for a detection in soil samples and plant material. Given that specific primers are available, the presented method will also allow quick and large-scale testing for other root pathogens. PMID:21442023

  1. Effect of (/sup 60/cobalt) gamma rays on growth and root rot diseases in mungbean (vigna radiata L.)

    International Nuclear Information System (INIS)

    Present investigation showed that gamma rays influences suppressive effect on root rot fungi such as Macrophomina phaseolina (Tassi) Goid, Rhizoctonia solani Kuhn and Fusarium spp., and inducive effect on growth parameters of mung bean (Vigna radiata L.). Seeds of mung bean were treated with gamma rays (/sup 60/Cobalt) at time periods of 0 and 4 minutes and stored for 90 days at room temperature to determine its effect on growth parameters and infection of root infecting fungi. All treatments of gamma rays enhanced the growth parameters as compared to untreated plants. Infection of M. phaseolina, R. solani and Fusarium spp., were significantly decreased on mung bean seeds treated with gamma rays. Gamma rays significantly increased the growth parameters and controlled the root rot fungi up to 90 days of storage of seeds. (author)

  2. Control of root rot of chickpea caused by Sclerotium rolfsii by different agents and gamma radiation

    International Nuclear Information System (INIS)

    Sclerotium rolfsii causes root rot disease in several crops including chickpea that result in low yield. Artificial infection of chickpea seedlings by S. rolfsii in vitro demonstrated that different tissues of the plant completely disintegrated by fungal infection. In vitro and green house pot experiments demonstrated that inducers in combination with fungicides, oils and bio agents resulted in about 80 % suppression of root rot disease. Treatments have no phyto toxic effect on chickpea seedlings at low doses. Gliocladium virens and Gliocladium deliquescens were effective as biocontrol agents against Sclerotium rolfsii. The percent of survival plants, fresh weight, dry weight and plant height of chickpea plants increased with different treatments with inducers compared with the control. Chlorophyll a, b, and total chlorophyll amounts increased to the maximum values. The activity of two plant enzymes, peroxidase and polyphenol oxidase increased. In this study, gamma irradiation of chickpea seeds at doses 5, 10, 15, 20, 25 and 30 Gy have negative effect on survival, plant height, fresh weight and dry weight of chickpea. The effect of gamma irradiation at doses 0.25, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 kGy on the antagonistic effect of Gliocladium virens and Gliocladium deliquescens against S. rolfsii were investigated. The results revealed that gamma irradiation increase the antagonistic effect of Gliocladium virens and Gliocladium deliquescens against S. rolfsii . Effect of gamma irradiation at doses of 0, 0.25, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 5 kGy on the mycelial growth and pathogenicity of S. rolfsii were investigated. The results revealed that gamma irradiation at doses 0.25 up to 3.0 kGy increase the pathogenicity of S. rolfsii but gamma irradiation at dose 5.0 kGy completely inhibited the growth of S. rolfsii. Extracellular polygalacturonase was characterized and purified by precipitation with 70 % ammonium sulfate, dialysis and gel filtration through Sephadex 75

  3. Reaction of selected soybean cultivars to Rhizoctonia root rot and other damping-off disease agents.

    Science.gov (United States)

    Amer, M A

    2005-01-01

    Eight soybean cultivars; Giza 21. Giza 22, Giza 35, Giza 82, Giza 83, Crawford, Holladay and Toamo were evaluated to Rhizoctonia root rot using agar plate and potted plant techniques. Data cleared that, in agar plate assay all soybean cultivars were moderately susceptible (MS), although the differences between them were significant (P=0.05). Generally, in potted assay, the reactions were resistant (R) or moderately resistant (MR) to root rots. Also, the differences between cultivars were significant (P=0.05). These cultivars were inoculated under greenhouse conditions with Fusarium solani, Macrophomina phaseolina, Rhizoctonia solani and Sclerotium rolfsii Generally, G21 had the least pre-emergence damping-off followed by Giza 35, Crawford and Giza 83 with averages of 19.0, 20.0, 20.5 and 21.5%, respectively. In case of post-emergence, Giza 35 had the least values, followed by Giza 21, Crawford and Giza 82 with averages 3.95, 4.10, 4.10 and 4.25%, respectively. Under naturally infested soil in the field conditions the reactions of the same cultivars to damping-off were evaluated in two successive seasons. In 2002 season, G35 had the least pre-emergence damping-off % followed by Giza 21 and Giza 22 with averages of 22.61, 24.33 and 29.33%, respectively. Also, G35 had the least post-emergence damping-off % followed by Toamo and Giza 21 with averages of 9.40, 10.33 and 10.41%, respectively. In 2003 season, the same trend was appeared with light grade where Giza 35 had the least pre-emergence damping of % followed by Giza 22 and Giza 21 with averages of 30.67, 31.00 and 36.67%, respectively and Giza 35 was the most resistant cultivar against post-emergence damping-off, followed by Giza 21 and Giza 22 with averages of 10.91, 11.32 and 11.80%, respectively. Generally, Giza 21 significantly surpassed the other cultivars in plant height, number of pods per plant and 100-seed weight. Moreover, also it had second grade with the other traits. PMID:16637203

  4. Release of SR98 Sugarbeet Germplasm with High Levels of Resistance to Rhizoctonia Damping-Off, Crown and Root Rot, and Fusarium

    Science.gov (United States)

    SR98 (PI 655951) is a sugarbeet germplasm with smooth, low soil tare root and high levels of resistance to damping-off and crown and root rot caused by Rhizoctonia solani (AG2-2). Previous smooth–root releases have been highly susceptible to diseases caused by R. solani, and the SR98 has incorporate...

  5. Wide variation in virulence and genetic diversity of binucleate Rhizoctonia isolates associated with root rot of strawberry in Western Australia.

    Directory of Open Access Journals (Sweden)

    Xiangling Fang

    Full Text Available Strawberry (Fragaria×ananassa is one of the most important berry crops in the world. Root rot of strawberry caused by Rhizoctonia spp. is a serious threat to commercial strawberry production worldwide. However, there is no information on the genetic diversity and phylogenetic status of Rhizoctonia spp. associated with root rot of strawberry in Australia. To address this, a total of 96 Rhizoctonia spp. isolates recovered from diseased strawberry plants in Western Australia were characterized for their nuclear condition, virulence, genetic diversity and phylogenetic status. All the isolates were found to be binucleate Rhizoctonia (BNR. Sixty-five of the 96 BNR isolates were pathogenic on strawberry, but with wide variation in virulence, with 25 isolates having high virulence. Sequence analysis of the internal transcribed spacers of the ribosomal DNA separated the 65 pathogenic BNR isolates into six distinct clades. The sequence analysis also separated reference BNR isolates from strawberry or other crops across the world into clades that correspond to their respective anastomosis group (AG. Some of the pathogenic BNR isolates from this study were embedded in the clades for AG-A, AG-K and AG-I, while other isolates formed clades that were sister to the clades specific for AG-G, AG-B, AG-I and AG-C. There was no significant association between genetic diversity and virulence of these BNR isolates. This study demonstrates that pathogenic BNR isolates associated with root rot of strawberry in Western Australia have wide genetic diversity, and highlights new genetic groups not previously found to be associated with root rot of strawberry in the world (e.g., AG-B or in Australia (e.g., AG-G. The wide variation in virulence and genetic diversity identified in this study will be of high value for strawberry breeding programs in selecting, developing and deploying new cultivars with resistance to these multi-genetic groups of BNR.

  6. Wide variation in virulence and genetic diversity of binucleate Rhizoctonia isolates associated with root rot of strawberry in Western Australia.

    Science.gov (United States)

    Fang, Xiangling; Finnegan, Patrick M; Barbetti, Martin J

    2013-01-01

    Strawberry (Fragaria×ananassa) is one of the most important berry crops in the world. Root rot of strawberry caused by Rhizoctonia spp. is a serious threat to commercial strawberry production worldwide. However, there is no information on the genetic diversity and phylogenetic status of Rhizoctonia spp. associated with root rot of strawberry in Australia. To address this, a total of 96 Rhizoctonia spp. isolates recovered from diseased strawberry plants in Western Australia were characterized for their nuclear condition, virulence, genetic diversity and phylogenetic status. All the isolates were found to be binucleate Rhizoctonia (BNR). Sixty-five of the 96 BNR isolates were pathogenic on strawberry, but with wide variation in virulence, with 25 isolates having high virulence. Sequence analysis of the internal transcribed spacers of the ribosomal DNA separated the 65 pathogenic BNR isolates into six distinct clades. The sequence analysis also separated reference BNR isolates from strawberry or other crops across the world into clades that correspond to their respective anastomosis group (AG). Some of the pathogenic BNR isolates from this study were embedded in the clades for AG-A, AG-K and AG-I, while other isolates formed clades that were sister to the clades specific for AG-G, AG-B, AG-I and AG-C. There was no significant association between genetic diversity and virulence of these BNR isolates. This study demonstrates that pathogenic BNR isolates associated with root rot of strawberry in Western Australia have wide genetic diversity, and highlights new genetic groups not previously found to be associated with root rot of strawberry in the world (e.g., AG-B) or in Australia (e.g., AG-G). The wide variation in virulence and genetic diversity identified in this study will be of high value for strawberry breeding programs in selecting, developing and deploying new cultivars with resistance to these multi-genetic groups of BNR. PMID:23405226

  7. Genetic Differentiation and Spatial Structure of Phellinus noxius, the Causal Agent of Brown Root Rot of Woody Plants in Japan

    OpenAIRE

    Akiba, Mitsuteru; Ota, Yuko; Tsai, Isheng J.; Hattori, Tsutomu; Sahashi, Norio; Kikuchi, Taisei

    2015-01-01

    Phellinus noxius is a pathogenic fungus that causes brown root rot disease in a variety of tree species. This fungus is distributed in tropical and sub-tropical regions of Southeast and East Asia, Oceania, Australia, Central America and Africa. In Japan, it was first discovered on Ishigaki Island in Okinawa Prefecture in 1988; since then, it has been found on several of the Ryukyu Islands. Recently, this fungus was identified from the Ogasawara (Bonin) Islands, where it has killed trees, incl...

  8. Microbiota Characterization of Compost Using Omics Approaches Opens New Perspectives for Phytophthora Root Rot Control

    Science.gov (United States)

    Blaya, Josefa; Marhuenda, Frutos C.; Pascual, Jose A.; Ros, Margarita

    2016-01-01

    Phytophthora root rot caused by Phytophthora nicotianae is an economically important disease in pepper crops. The use of suppressive composts is a low environmental impact method for its control. Although attempts have been made to reveal the relationship between microbiota and compost suppressiveness, little is known about the microorganisms associated with disease suppression. Here, an Ion Torrent platform was used to assess the microbial composition of composts made of different agro-industrial waste and with different levels of suppressiveness against P. nicotianae. Both bacterial and fungal populations responded differently depending on the chemical heterogeneity of materials used during the composting process. High proportions (67–75%) of vineyard pruning waste were used in the most suppressive composts, COM-A and COM-B. This material may have promoted the presence of higher relative abundance of Ascomycota as well as higher microbial activity, which have proved to be essential for controlling the disease. Although no unique fungi or bacteria have been detected in neither suppressive nor conducive composts, relatively high abundance of Fusarium and Zopfiella were found in compost COM-B and COM-A, respectively. To the best of our knowledge, this is the first work that studies compost metabolome. Surprisingly, composts and peat clustered together in principal component analysis of the metabolic data according to their levels of suppressiveness achieved. This study demonstrated the need for combining the information provided by different techniques, including metagenomics and metametabolomics, to better understand the ability of compost to control plant diseases. PMID:27490955

  9. Microbiota Characterization of Compost Using Omics Approaches Opens New Perspectives for Phytophthora Root Rot Control.

    Science.gov (United States)

    Blaya, Josefa; Marhuenda, Frutos C; Pascual, Jose A; Ros, Margarita

    2016-01-01

    Phytophthora root rot caused by Phytophthora nicotianae is an economically important disease in pepper crops. The use of suppressive composts is a low environmental impact method for its control. Although attempts have been made to reveal the relationship between microbiota and compost suppressiveness, little is known about the microorganisms associated with disease suppression. Here, an Ion Torrent platform was used to assess the microbial composition of composts made of different agro-industrial waste and with different levels of suppressiveness against P. nicotianae. Both bacterial and fungal populations responded differently depending on the chemical heterogeneity of materials used during the composting process. High proportions (67-75%) of vineyard pruning waste were used in the most suppressive composts, COM-A and COM-B. This material may have promoted the presence of higher relative abundance of Ascomycota as well as higher microbial activity, which have proved to be essential for controlling the disease. Although no unique fungi or bacteria have been detected in neither suppressive nor conducive composts, relatively high abundance of Fusarium and Zopfiella were found in compost COM-B and COM-A, respectively. To the best of our knowledge, this is the first work that studies compost metabolome. Surprisingly, composts and peat clustered together in principal component analysis of the metabolic data according to their levels of suppressiveness achieved. This study demonstrated the need for combining the information provided by different techniques, including metagenomics and metametabolomics, to better understand the ability of compost to control plant diseases. PMID:27490955

  10. Zinc Induced Enzymatic Defense Mechanisms in Rhizoctonia Root Rot Infected Clusterbean Seedlings

    Directory of Open Access Journals (Sweden)

    Neha Wadhwa

    2014-01-01

    Full Text Available This investigation was planned to determine the effect of different concentrations of zinc (Zn on biochemical constituents of clusterbean, which play an important role in disease resistance mechanisms. Clusterbean seedlings were grown with 0, 10, or 20 mg Zn kg−1 soil treatments in earthen pots filled with 700 g inoculated soil. Soil was inoculated by pretreatment with 250 mg (wet weight of Rhizoctonia inoculums per pot. A similar set was maintained in uninoculated soil. Root rot incidence decreased to 41 and 27 per cent with 10 and 20 mg Zn kg−1 soil treatments, respectively, as compared to 68 percent at control. Antioxidative enzyme activity (polyphenol oxidase, peroxidase, phenylalanine ammonia lyase, and tyrosine ammonia lyase increased in inoculated seedlings and was increased further by 20 mg Zn kg−1 soil treatment. Antioxidative enzymes play an important role against fungal invasion, as peroxidase is involved in the formation of barrier via lignifications at the site of pathogen penetration. PAL and TAL play a key role in phenylpropanoid metabolism and could perform defense-related functions. Zn acts as a cofactor for these enzymes, so it can be concluded that Zn may be used as a soil-nutritive agent to increase resistance in plants against fungal diseases.

  11. Incidence of root rot diseases of soybean in Multan Pakistan and its management by the use of plant growth promoting rhizobacteria

    International Nuclear Information System (INIS)

    Eight villages in Multan district were surveyed to record incidence of disease and losses of soybean (Glycine max L.) caused by root rot fungi. The root incidence ranged 10-17% and losses ranged 6.75-15.5%. The evaluation of four PGPR isolates was used in combination with organic amendment for the management of root-rot disease incidence and to reduce the population of root pathogenic fungi and to increase the yield in field. This study demonstrated effective biological control by the PGPR isolates tested, thereby indicating the possibility of application of rhizobacteria for control of soil bor ne diseases of soybean in Pakistan and other countries. (author)

  12. IMPROVMENT BIOCONTROL OF DAMPING-OFF AND ROOT ROT/WILT OF FABA BEAN BY SALICYLIC ACID AND HYDROGEN PEROXIDE

    Directory of Open Access Journals (Sweden)

    Montaser F. Abdel-Monaim

    2013-04-01

    Full Text Available Rhizoctonia solani, Fusarium solani, F. oxysporum and Macrophomina phaseolina were found to be associated with root rot and wilt symptoms of faba bean plants collected from different fields in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40 causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride, Bacillus megaterium and chemical inducers (salicylic acid and hydrogen peroxide individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promotion of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi.Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA+ B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/ wilt severity and increased survival of plants. Also, these treatments increased fresh and dry weights of the survived plants in pots compared with control.  The combination of biocontrol agents and chemical inducers were more effective than using them individually and SA+ T. viride was the best treatment in this respect. Under field conditions, all these treatments significantly increased growth parameters (plant height and No. of branches plant-1 and yield components (No. of pods and seedsplant-1, weight of 100 seeds and total yield feddan-1 and protein content in both seasons (2010-2011 and 2011-2012. Faba bean seeds soaked in SA+ T. viride and SA+ B. megaterium were recorded the highest growth parameters and yield components. Generally, the combination of biocontrol agents and

  13. First Report of Sclerotinia White Rot Caused by Sclerotinia nivalis on Panax ginseng in Korea

    OpenAIRE

    Hye Sun Cho; Jeong-Sup Shin; Jae-Hyun Kim; Tae-Kyun Hong; Dae-Hui Cho; Je Yong Kang

    2013-01-01

    Sclerotinia white rot disease was observed on 5 and 6-year-old ginseng (Panax ginseng) roots in Hongchun,Cheorwon, and Yanggu, Gangwon Province, Korea from 2006 to 2010. Symptoms included a brownishwatery soft rot of the roots, and black sclerotia were often found on the rotten roots. The causal agent of thedisease was identified as Sclerotinia nivalis based on cultural characteristics and sequence analyses of theinternal transcribed spacer region of rDNA and β-tubulin gene with 100% sequence...

  14. Effect of Environment and Sugar Beet Genotype on Root Rot Development and Pathogen Profile During Storage.

    Science.gov (United States)

    Liebe, Sebastian; Varrelmann, Mark

    2016-01-01

    Storage rots represent an economically important factor impairing the storability of sugar beet by increasing sucrose losses and invert sugar content. Understanding the development of disease management strategies, knowledge about major storage pathogens, and factors influencing their occurrence is crucial. In comprehensive storage trials conducted under controlled conditions, the effects of environment and genotype on rot development and associated quality changes were investigated. Prevalent species involved in rot development were identified by a newly developed microarray. The strongest effect on rot development was assigned to environment factors followed by genotypic effects. Despite large variation in rot severity (sample range 0 to 84%), the spectrum of microorganisms colonizing sugar beet remained fairly constant across all treatments with dominant species belonging to the fungal genera Botrytis, Fusarium, and Penicillium. The intensity of microbial tissue necrotization was strongly correlated with sucrose losses (R² = 0.79 to 0.91) and invert sugar accumulation (R² = 0.91 to 0.95). A storage rot resistance bioassay was developed that could successfully reproduce the genotype ranking observed in storage trials. Quantification of fungal biomass indicates that genetic resistance is based on a quantitative mechanism. Further work is required to understand the large environmental influence on rot development in sugar beet. PMID:26474333

  15. 油梨根腐病发病规律及防治技术%Occurrence regularity of Avocado Root Rot and Its Control Techniques

    Institute of Scientific and Technical Information of China (English)

    劳有德; 陈川

    2016-01-01

    油梨根腐病是油梨根部重要病害,近年来逐渐增多,严重时可造成油梨整株死亡,已成为油梨产业发展的重要病害。目前广西已发现有4种油梨根腐病,是较难防治的土传病害。重点介绍4种油梨根腐病的特点、发生、病因、症状等,从农业、物理、生物、化学防治方面介绍油梨根腐病的防治技术。%Avocado root rot is one of the most important root diseases on avocado, the disease is increasing in recent years. It can cause the death of the whole plant of avocado when this disease becomes seriously. The avocado root rot disease has become an important disease in avocado industry. Nowadays, there are four kinds of avocado root rot diseases are found in GuangXi Province. It is more difficult to control these soil borne diseases. This paper introduces the traits, causes, symptoms and occurrence of avocado root rot disease. And then, the control techniques for avocado root rot in agricultural, physical, biological and chemical control field and so on are introduced.

  16. Biological Control of Pathogens Causing Root Rot Complex in Field Pea Using Clonostachys rosea Strain ACM941.

    Science.gov (United States)

    Xue, Allen G

    2003-03-01

    ABSTRACT Pea root rot complex (PRRC), caused by Alternaria alternata, Aphanomyces euteiches, Fusarium oxysporum f. sp. pisi, F. solani f. sp. pisi, Mycosphaerella pinodes, Pythium spp., Rhizoctonia solani, and Sclerotinia sclerotiorum, is a major yield-limiting factor for field pea production in Canada. A strain of Clonostachys rosea (syn. Gliocladium roseum), ACM941 (ATCC 74447), was identified as a mycoparasite against these pathogens. When grown near the pathogen, ACM941 often was stimulated to produce lateral branches that grew directly toward the pathogen mycelium, typically entwining around the pathogen mycelium. When applied to the seed, ACM941 propagated in the rhizosphere and colonized the seed coat, hypocotyl, and roots as the plant developed and grew. ACM941 significantly reduced the recovery of all fungal pathogens from infected seed, increased in vitro seed germination by 44% and seedling emergence by 22%, and reduced root rot severity by 76%. The effects were similar to those of thiram fungicide, which increased germination and emergence by 33 and 29%, respectively, and reduced root rot severity by 65%. When soil was inoculated with selected PRRC pathogens in a controlled environment, seed treatment with ACM941 significantly increased emergence by 26, 38, 28, 13, and 21% for F. oxysporum f. sp. pisi, F. solani f. sp. pisi, M. pinodes, R. solani, and S. sclerotiorum, respectively. Under field conditions from 1995 to 1997, ACM941 increased emergence by 17, 23, 22, 13, and 18% and yield by 15, 6, 28, 6, and 19% for the five respective pathogens. The seed treatment effects of ACM941 on these PRRC pathogens were greater or statistically equivalent to those achieved with thiram. Results of this study suggest that ACM941 is an effective bioagent in controlling PRRC and is an alternative to existing chemical products. PMID:18944343

  17. The root rot fungus Armillaria mellea introduced into South Africa by early Dutch settlers.

    Science.gov (United States)

    Coetzee, M P; Wingfield, B D; Harrington, T C; Steimel, J; Coutinho, T A; Wingfield, M J

    2001-02-01

    Dead and dying oak (Quercus) and numerous other woody ornamental trees and shrubs showing signs and symptoms of Armillaria root rot were identified in the Company Gardens, Cape Town, South Africa, which were established in the mid-1600s by the Dutch East Indies Trading Company. Nineteen isolates from dying trees or from mushrooms were collected and analysed to identify and characterize the Armillaria sp. responsible for the disease. The AluI digestion of the amplified product of the first intergenic spacer region (IGS-1) of the rRNA operon of 19 isolates from the Company Gardens was identical to that of some of the European isolates of A. mellea s. s. The IGS-1 region and the internal transcribed spacers (ITS) were sequenced for some of the Cape Town isolates. Phylogenetic analyses placed the Cape Town isolates in the European clade of A. mellea, which is distinct from the Asian and North American clades of this species. Identification based on sexual compatibility was conducted using A. mellea tester strains in diploid-haploid pairings, which showed some compatibility between the Cape Town isolates and testers from Europe. Somatic compatibility tests (diploid-diploid pairings) and DNA fingerprinting with multilocus, microsatellite probes indicated that the Cape Town isolates were genetically identical and may have resulted from vegetative (clonal) spread from a single focus in the centre of the original Company Gardens (c. 1652). The colonized area is at least 345 m in diameter. Assuming a linear spread rate underground of 0.3 m/year to 1.6 m/year, the genet (clone) was estimated to be between 108 and 575 years old. These data suggest that A. mellea was introduced into Cape Town from Europe, perhaps on potted plants, such as grapes or citrus, planted in the Company Gardens more than 300 years ago. PMID:11298953

  18. Root interactions in a maize/soybean intercropping system control soybean soil-borne disease, red crown rot.

    Directory of Open Access Journals (Sweden)

    Xiang Gao

    Full Text Available BACKGROUND: Within-field multiple crop species intercropping is well documented and used for disease control, but the underlying mechanisms are still unclear. As roots are the primary organ for perceiving signals in the soil from neighboring plants, root behavior may play an important role in soil-borne disease control. PRINCIPAL FINDINGS: In two years of field experiments, maize/soybean intercropping suppressed the occurrence of soybean red crown rot, a severe soil-borne disease caused by Cylindrocladium parasiticum (C. parasiticum. The suppressive effects decreased with increasing distance between intercropped plants under both low P and high P supply, suggesting that root interactions play a significant role independent of nutrient status. Further detailed quantitative studies revealed that the diversity and intensity of root interactions altered the expression of important soybean PR genes, as well as, the activity of corresponding enzymes in both P treatments. Furthermore, 5 phenolic acids were detected in root exudates of maize/soybean intercropped plants. Among these phenolic acids, cinnamic acid was released in significantly greater concentrations when intercropped maize with soybean compared to either crop grown in monoculture, and this spike in cinnamic acid was found dramatically constrain C. parasiticum growth in vitro. CONCLUSIONS: To the best of our knowledge, this study is the first report to demonstrate that intercropping with maize can promote resistance in soybean to red crown rot in a root-dependent manner. This supports the point that intercropping may be an efficient ecological strategy to control soil-borne plant disease and should be incorporated in sustainable agricultural management practices.

  19. Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance

    Institute of Scientific and Technical Information of China (English)

    LI Wen-juan; HE Ping; JIN Ji-yun

    2010-01-01

    To study the mechanism of potassium(K)application on improvement of maize resistance to stalk rot at cellular level,scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen.In K deficient treatment,parenchyma cells of stalk pith had abnormal structure,and the cell wall between upper and lower adjacent cell was damaged,resulting in the loss of connections between vascular cells and insufficient supporting capacity.However,an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall,and prevent the invasion of pathogen effectively.Moreover,K treated root cell had abundant golgi apparatus,which could excrete large amount of secretions to degrade mycelium.Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the development of the mycelium.Improved K nutrition could increase the resistant ability of maize plant to stalk rot,through keeping cell structure stability,preventing the expansion of intracellular space to reduce the chances of pathogen invasions,and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell.

  20. Gene-for-gene relationships between strawberry and the causal agent of red stele root rot, Phytophthora fragariae var. fragariae.

    OpenAIRE

    Weg, van de, W.E.

    1997-01-01

    Red stele (red core) root rot is the major soil-borne disease of strawberries (Fragaria spp.) in many areas with cool, moist soil conditions. It is caused by the soil-borne fungus Phytophthora fragariae var. fragariae. Red stele is a quarantine disease in Europe with a zero tolerance for commercial stock plants. Any lot of such plants with even just a trace of the disease has to be destroyed. The plot on which the plants were harvested has to be abandoned for commercial strawberry propagation...

  1. Conidioma production of the white root rot fungus [Rosellinia] in axenic culture under near-ultraviolet light radiation

    International Nuclear Information System (INIS)

    Conidiomata of the white root rot fungus were produced in axenic culture under near-ultraviolet light radiation. Pieces of sterilized Japanese pear twigs were placed on 7-day-old oatmeal agar culture in plates. The plates were further incubated for 5 days and then illuminated by near-ultraviolet light. Synnemata developed on the twigs within 5 weeks in 19 of 20 isolates tested, and conidia were observed in 12 of the 19 isolates. The synnemata and conidia produced were morphologically identical to those of Dematophora necatrix

  2. Mutation breeding against black pod (Phytophthora pod rot) disease of cacao (Theobroma cacao)

    International Nuclear Information System (INIS)

    Black pod rot disease, caused by Phytophthora palmivora, is an important disease of cacao (Theobroma cacao L.) in Nigeria and other cacao producing countries of West Africa and Latin America. A naturally occurring source of genetic resistance to the disease has not been found. This paper completes the report, the first part of which was published in Induced Mutations in Vegetatively Propagated Plants, IAEA, Vienna (1973). The survivors of the irradiated seedlings reported on in this publication were transplanted to the field along with their controls. When the Phytophthora pod disease season began in 1973, all experimental plants along with the controls were sprayed with active and freshly prepared dense sporangial suspension of P. palmivora. Observations on Phytophthora infection were recorded at two-weekly intervals for three months. Results were pooled for each set of experimental plants, after having confirmed that no marked difference appeared among individual plants of each group. Contrary to the observations recorded at the nursery stage, all experimental plants that showed no infection indicated disease infection levels normally characteristic of the F3 Amazon cultivar of Cacao in Nigeria. Although the nursery and the field data are difficult to reconcile and interpret, it is suggested that probably temporary disease tolerance/resistance, which some irradiated plants showed at the nursery (seedling) stage, was lost as the plants matured, thus suggesting different resistance factor systems for juvenile and mature cacao trees. (author)

  3. Role of Antagonistic Microorganisms and Organic Amendment in Stimulating the Defense System of Okra Against Root Rotting Fungi.

    Science.gov (United States)

    Shafique, Hafiza Asma; Sultana, Viqar; Ara, Jehan; Ehteshamul-Haque, Syed; Athar, Mohammad

    2015-01-01

    Without application of chemical pesticides control of soilborne diseases is a great challenge. Stimulation of natural plant's defense is considered as one of the most promising alternative strategy for crop protection. Organic amendment of soil besides direct suppressing the pathogen, has been reported to have an influence on phytochemicals in plants. In the present study, Pseudomonas aeruginosa, a plant growth promoting rhizobacterium and Paecilomyces lilacinus, an egg parasite of root knot and cysts nematodes were examined individually and in combination in soil amended with cotton cake for suppressing the root rotting fungi and stimulating the synthesis of polyphenols and improving the antioxidant status in okra. Application of P. aeruginosa and P. lilacinus in soil amended with cotton cake significantly (P Rhizoctonia solani. Combine use of biocontrol agents in cotton cake amended soil showed maximum positive impact on plant growth, polyphenol concentration and antioxidant activity in okra. PMID:26373176

  4. Biocontrol traits of plant growth suppressive arbuscular mycorrhizal fungi against root rot in tomato caused by Pythium aphanidermatum

    DEFF Research Database (Denmark)

    Larsen, John; Graham, James H.; Cubero, Jaime;

    2012-01-01

    Arbuscular mycorrhizal (AM) fungi known to cause plant growth depressions in tomato were examined for their biocontrol effects against root rot caused by Pythium aphanidermatum. The main hypothesis was that plant growth suppressive AM fungi would elicit a defence response in the host plant reduci...

  5. Genetic architecture and evolution of the mating type locus in fusaria that cause soybean sudden death syndrome and bean root rot

    Science.gov (United States)

    Fusarium tucumaniae is the only known sexually reproducing species among the seven closely related fusaria that cause soybean sudden death syndrome (SDS) or bean root rot (BRR). Laboratory mating of F. tucumaniae required two mating-compatible strains, indicating that it is heterothallic. To assess ...

  6. Soil amendment with Aerva javanica (Burm. F. Juss. ex Schult. in the control of root rot fungi of cowpea [Vigna unguiculata (L. Walp.] and mung bean [Vigna radiata (L.

    Directory of Open Access Journals (Sweden)

    Naheed Ikram

    2012-10-01

    Full Text Available Root rot fungi cause severe losses of crop plants, so the present work was carried out to determine the effect of Aerva javanica parts powder on root infecting fungi of mung bean (Vigna radiata (L. and cowpea (Vigna unguiculata (L. Walp.. A. javanica parts (stem, leaves and flower were used as soil amendments at 0.1, 1 and 5% to check the effectiveness on growth parameters. All the plant parts showed a significant reduction in root rot fungi like Fusarium spp., Rhizoctonia solani Kuhn, and Macrophomina phaseolina (Tassi Goid. It was noted that germination percentage, fresh weight, leaf area and number of nodules were significantly higher and the inhibitory effect on root rot fungi increased when the soil was amended with A. javanica leaves at 1%. Thus, among all the treatments, A. javanica leaves at 1% were found to be the most effective against root rot fungi.

  7. First report of black rot of apple caused by Diplodia seriata in Washington state.

    Science.gov (United States)

    In July 2014, decayed ‘Fuji’ apple fruit (Malus × domestica Borkh.) were observed and sampled from commercial orchards in Mattawa (Grant County) in Washington State. Fruit rot symptoms appeared to originate mainly from infections at either the calyx-end (floral parts) of the fruit or wounds on the f...

  8. Management of root rot and root knot disease of mungbean with the application of mycorrhizospheric fluorescent pseudomonas under field condition

    International Nuclear Information System (INIS)

    The mycorrhizosphere is the region around a mycorrhizal fungus in which nutrients released from the hyphae increases microbial population and its activities. In this study five mycorrhizospheric fluorescent Pseudomonas (MRFP) were evaluated for biocontrol potential under field condition using mungbean (Vigna radiata) as test plant. MRFP-249 significantly reduced Fusarium solani, Rhizoctonia solani and Macrophomina phaseolina. Whereas MRFP246 and MRFP-247 were also found effective against M. phaseolina. Mycorrhizospheric fluorescent Pseudomonas were also found effective against root knot nematode by reducing the galls on roots and nematode's penetration in roots. Highest fresh shoot weight and plant height was produced by MRFP-248. Plants grown in soil treated with Pseudomonas showed higher number of VAM spores around the mungbean roots than untreated control plants. The mycorrhizal symbiosis should not be considered merely as bipartite, plant-fungus interaction, but should instead include the associated microorganisms, particularly fluorescent Pseudomonas. (author)

  9. Isolation, characterization, and formulation of antagonistic bacteria for the management of seedlings damping-off and root rot disease of cucumber.

    Science.gov (United States)

    Khabbaz, Salah Eddin; Abbasi, Pervaiz A

    2014-01-01

    Antagonistic bacteria are common soil inhabitants with potential to be developed into biofungicides for the management of seedling damping-off, root rot, and other soil-borne diseases of various crops. In this study, antagonistic bacteria were isolated from a commercial potato field and screened for their growth inhibition of fungal and oomycete pathogens in laboratory tests. The biocontrol potential of the 3 most effective antagonistic bacteria from the in vitro tests was evaluated against seedling damping-off and root rot of cucumber caused by Pythium ultimum. Based on phenotypic characteristics, biochemical tests, and sequence analysis of 16S-23S rDNA gene, the 3 antagonistic bacteria were identified as Pseudomonas fluorescens (isolate 9A-14), Pseudomonas sp. (isolate 8D-45), and Bacillus subtilis (isolate 8B-1). All 3 bacteria promoted plant growth and suppressed Pythium damping-off and root rot of cucumber seedlings in growth-room assays. Both pre- and post-planting application of these bacteria to an infested peat mix significantly increased plant fresh masses by 113%-184% and percentage of healthy seedlings by 100%-290%, and decreased damping-off and root rot severity by 27%-50%. The peat and talc formulations of these antagonistic bacteria applied as seed or amendment treatments to the infested peat mix effectively controlled Pythium damping-off and root rot of cucumber seedlings and enhanced plant growth. The survival of all 3 antagonistic bacteria in peat and talc formulations decreased over time at room temperature, but the populations remained above 10(8) CFU/g during the 180-day storage period. The peat formulation of a mixture of 3 bacteria was the best seed treatment, significantly increasing the plant fresh masses by 245% as compared with the Pythium control, and by 61.4% as compared with the noninfested control. This study suggests that the indigenous bacteria from agricultural soils can be developed and formulated as biofungicides for minimizing

  10. INFLUENCE OF NPK AND LIME APLICATION ON ERVA-MATE GROWTH, ROOT-ROT SEVERITY AND SOIL FUNGI POPULATION1

    Directory of Open Access Journals (Sweden)

    Igor Poletto

    2011-09-01

    Full Text Available The present work evaluated the influence of the application of NPK and liming doses in the soil, on the growth of Erva-mate, the severity of rot-root and the fungi population of the soil. To do so, an experiment was installed at the green house, in the Forest Nursery of UFSM, using an experimental design completely randomized factorial 4x3x4 (Factor F: Fusarium spp. inoculation; Factor C: soil limestone; Factor A: NPK doses , totaling 48 treatments. The seedlings were cultivated in vases containing 2 kg of soil, classified as ‘Red-Yellow Argisoil’ (clay soil. At the end of the experiment was measured the stem diameter, height of the aerial part, leaves number, aerial dry biomass, root dry biomass and total dry biomass of the seedlings. Also, the soil was collected, from each treatment, for the chemical analysis and the counting of the fungi population. It was observed that the association among application of NPK and liming in the soil hampered the development of Erva-mate seedlings. The analysis of some variables suggests that the limestone absence provided greater resistance of seedlings to the attack of Fusarium spp. or the severity of Fusarium spp. was reduced in lower pH. The fungi population of the soil presented varied behavior depending on the applied treatments.

  11. Pathogenicity of some Rhizoctonia solaniz isolates associated with root/collar rots on the cultivars of bean in greenhouse.

    Science.gov (United States)

    Bohlooli, A; Okhovvat, S M; Javan-Nikkhah, M

    2006-01-01

    One hundred and eighteen isolates of Rhizoctonia solani were gathered from infected roots and hypocotyls of bean (Phaseolus vulgaris L.) grown in the fields of Tehran Province, Iran. Two isolates of the collected samples belonged to binucleate and 81 isolates to multinucleate of R. solani. The multinucleate isolates showed different anastomosis groups as AG-4 (subg. AG-4 HGI, AG-4HGII), AG-6 and AG-2. In greenhouse, pathogenicity tests carried out on bean cv. Naz in randomized design with 4 replications and each replication (pots) with 5 seeds of bean. Infection was done with seeds of wheat which were infected to the fungus with pasteurized soil. Results showed that the highest disease severity was caused by AG-4 (Rs21) isolates, whereas AG-4 (Rs74) isolates were weakly pathogenic with 90% and 21% infection, respectively. In this test the major pathogenic isolates belonged to AG-4 and they caused seed rot and damping-off of bean and AG-6 isolates were non-pathogenic. Five isolates of the fungus with major pathogenicity (Rs7, Rs18, Rs21, Rs62 and Rs71) selected and used for the reaction with different cultivars of bean. In this test, the cultivars and lines of bean (Pinto, red, white, green) studied in factorial experiment as randomized block design with 4 replications (pots). Results showed that none of the cultivars was completely resistant, however green bean cv. Sanry and pinto cv. Shad with number 4.8 disease severities had the highest susceptibility to seed rot and damping-off and red bean cv. Goli with 2.58 had the lowest susceptibility to the infection. Reaction of the cultivars and lines to the isolates of R. solani was significantly different at 1% level. Isolates of the fungus, Rs7, Rs21 with 84%, 90% pathogenicity was more virulent than the others. PMID:17390878

  12. Genetics and Molecular Mapping of Black Rot Resistance Locus Xca1bc on Chromosome B-7 in Ethiopian Mustard (Brassica carinata A. Braun)

    Science.gov (United States)

    Sharma, Brij Bihari; Kalia, Pritam; Yadava, Devendra Kumar; Singh, Dinesh; Sharma, Tilak Raj

    2016-01-01

    Black rot caused by Xanthomonas campestris pv. campestris (Pam.) Dowson is the most destructive disease of cauliflower causing huge loss to the farmers throughout the world. Since there are limited sources of resistance to black rot in B. oleracea (C genome Brassica), exploration of A and B genomes of Brassica was planned as these were thought to be potential reservoirs of black rot resistance gene(s). In our search for new gene(s) for black rot resistance, F2 mapping population was developed in Brassica carinata (BBCC) by crossing NPC-17, a susceptible genotype with NPC-9, a resistant genotype. Out of 364 Intron length polymorphic markers and microsatellite primers used in this study, 41 distinguished the parental lines. However, resistant and susceptible bulks could be distinguished by three markers At1g70610, SSR Na14-G02 and At1g71865 which were used for genotyping of F2 mapping population. These markers were placed along the resistance gene, according to order, covering a distance of 36.30 cM. Intron length polymorphic markers At1g70610 and At1g71865 were found to be linked to black rot resistance locus (Xca1bc) at 6.2 and 12.8 cM distance, respectively. This is the first report of identification of markers linked to Xca1bc locus in Brassica carinata on B-7 linkage group. Intron length polymorphic markers provided a novel and attractive option for marker assisted selection due to high cross transferability and cost effectiveness for marker assisted alien gene introgression into cauliflower. PMID:27023128

  13. Organic amendments conditions on the control of Fusarium crown and root rot of asparagus caused by three Fusarium spp.

    Directory of Open Access Journals (Sweden)

    Ana I. Borrego-Benjumea

    2015-12-01

    Full Text Available Fusarium oxysporum (Fo, F. proliferatum (Fp and F. solani (Fs are causal agents associated with roots of asparagus affected by crown and root rot, a disease inflicting serious losses worldwide. The propagule viability of Fusarium spp. was determined on substrate artificially infested with Fo5, Fp3 or Fs2 isolates, amended with either poultry manure (PM, its pellet (PPM, or olive residue compost (ORC and, thereafter, incubated at 30 or 35°C for different periods. Inoculum viability was significantly affected by these organic amendments (OAs in combination with temperature and incubation period. The greatest reduction in viability of Fo5 and Fs2 occurred with PPM and loss of viability achieved was higher at 35°C than at 30ºC, and longer incubation period (45 days. However, the viability of Fp3 did not decrease greatly in most of the treatments, as compared to the infested and un-amended control, when incubated at 30ºC. After incubation, seedlings of asparagus `Grande´ were transplanted into pots containing substrates infested with the different species of Fusarium. After three months in greenhouse, symptoms severity in roots showed highly significant decreases, but Fp3 caused lower severity than Fo5 and Fs2. Severity reduction was particularly high at 30ºC (by 15 days incubation for Fs2 and by 30-45 days for Fo5, after PPM treatment, as well as PM-2% for Fo5 and Fs2 incubated during 30 and 45 days at both temperatures, and with ORC (15-30 days incubation. Moreover, assessment of plants fresh weight showed significantly high increases in Fo5 and Fs2, with some rates of the three OAs tested, depending on incubation period and temperature.

  14. 丹参根腐病原菌的分离与鉴定%Isolation and identification of root rot pathogen of Salvia miltiorrhiza Bunge

    Institute of Scientific and Technical Information of China (English)

    袁孟娟; 藏香银; 韩军; 陈芳

    2015-01-01

    为进一步了解丹参( Salvia miltiorrhiza Bunge)根腐病病原菌的种类及生物学特性,采用组织分离法从丹参根腐病样本中分离到1株真菌,经致病性测定、形态学观察和分子生物学鉴定,将其鉴定为腐皮镰刀菌( Fu-sarium solani )。%In order to further understand the variety and biology characteristics of the pathogens of Salvia miltiorrhiza Bunge root rot, one strain of fungi was isolated from the root rot samples of S.miltiorrhiza Bunge by tissue isolation.According to the pathogenicity test and the morphological observation of the pathogen, as well as molecular biological identification, it was identified as Fusarium solani.

  15. The Effects of Arbuscular Mycorrhizal Fungus (AMF) and Humic Acid on the Growth of Pepper (Capsicum annuum L.) Plant and Root Rot Disease Caused by Phytophthora capsici Leonian

    OpenAIRE

    ASLANPAY, Burcu; Semra DEMİR

    2015-01-01

    In this study, the effects of singular and double combinations of Arbuscular Mycorrhizal Fungi (AMF) and humic acid (HA) were investigated on the growth of pepper (Capsicum annuum L.) and rot root disease caused by Phytophthora capsici Leonian which has been known as an important problem of pepper cultivation and leading yield losses. Under controlled conditions, four F1 pepper cultivars (Ergenekon, Bafra, Sirena and Yıldız) were inoculated with three different AMF strains (Glomus intraradice...

  16. Differential Responses of Vanilla Accessions to Root Rot and Colonization by Fusarium oxysporum f. sp. radicis-vanillae

    Science.gov (United States)

    Koyyappurath, Sayuj; Conéjéro, Geneviève; Dijoux, Jean Bernard; Lapeyre-Montès, Fabienne; Jade, Katia; Chiroleu, Frédéric; Gatineau, Frédéric; Verdeil, Jean Luc; Besse, Pascale; Grisoni, Michel

    2015-01-01

    Root and stem rot (RSR) disease caused by Fusarium oxysporum f. sp. radicis-vanillae (Forv) is the most damaging disease of vanilla (Vanilla planifolia and V. × tahitensis, Orchidaceae). Breeding programs aimed at developing resistant vanilla varieties are hampered by the scarcity of sources of resistance to RSR and insufficient knowledge about the histopathology of Forv. In this work we have (i) identified new genetic resources resistant to RSR including V. planifolia inbreds and vanilla relatives, (ii) thoroughly described the colonization pattern of Forv into selected vanilla accessions, confirming its necrotic non-vascular behavior in roots, and (iii) evidenced the key role played by hypodermis, and particularly lignin deposition onto hypodermal cell walls, for resistance to Forv in two highly resistant vanilla accessions. Two hundred and fifty-four vanilla accessions were evaluated in the field under natural conditions of infection and in controlled conditions using in vitro plants root-dip inoculated by the highly pathogenic isolate Fo072. For the 26 accessions evaluated in both conditions, a high correlation was observed between field evaluation and in vitro assay. The root infection process and plant response of one susceptible and two resistant accessions challenged with Fo072 were studied using wide field and multiphoton microscopy. In susceptible V. planifolia, hyphae penetrated directly into the rhizodermis in the hairy root region then invaded the cortex through the passage cells where it induced plasmolysis, but never reached the vascular region. In the case of the resistant accessions, the penetration was stopped at the hypodermal layer. Anatomical and histochemical observations coupled with spectral analysis of the hypodermis suggested the role of lignin deposition in the resistance to Forv. The thickness of lignin constitutively deposited onto outer cell walls of hypodermis was highly correlated with the level of resistance for 21 accessions

  17. First report of root rot of Chicory caused by Phytophthora cryptogea in Chile

    Science.gov (United States)

    Chicory (Cichorium intybus L. var sativum Bisch.), a relatively new high value crop in Chile, was introduced for commercial production of inulin. Inulins are polysaccharides extracted from chicory tap roots that are used in processed foods due to their beneficial gastrointestinal properties. Approxi...

  18. Effect of integrated application of Biopolitsyd and Fosfoenteryn on root rot infestation and productivity of cucumber

    OpenAIRE

    N. Opryshko; Y. Ternovyi; N. Pasichnyk

    2014-01-01

    This paper deals with environmental and agronomic feasibility of integrated application of Biopolitsyd and Fosfoenteryn for preplant treatment of cucumber seeds. It has been found, that the complex inoculation enhances a yield of cucumber, reduces the number of micromycetes in the root zone of plants, improves a phytosanitary condition of crops

  19. Genetic Differentiation and Spatial Structure of Phellinus noxius, the Causal Agent of Brown Root Rot of Woody Plants in Japan.

    Science.gov (United States)

    Akiba, Mitsuteru; Ota, Yuko; Tsai, Isheng J; Hattori, Tsutomu; Sahashi, Norio; Kikuchi, Taisei

    2015-01-01

    Phellinus noxius is a pathogenic fungus that causes brown root rot disease in a variety of tree species. This fungus is distributed in tropical and sub-tropical regions of Southeast and East Asia, Oceania, Australia, Central America and Africa. In Japan, it was first discovered on Ishigaki Island in Okinawa Prefecture in 1988; since then, it has been found on several of the Ryukyu Islands. Recently, this fungus was identified from the Ogasawara (Bonin) Islands, where it has killed trees, including rare endemic tree species. For effective control or quarantine methods, it is important to clarify whether the Japanese populations of P. noxius are indigenous to the area or if they have been introduced from other areas. We developed 20 microsatellite markers from genome assembly of P. noxius and genotyped 128 isolates from 12 of the Ryukyu Islands and 3 of the Ogasawara Islands. All isolates had unique genotypes, indicating that basidiospore infection is a primary dissemination method for the formation of new disease foci. Genetic structure analyses strongly supported genetic differentiation between the Ryukyu populations and the Ogasawara populations of P. noxius. High polymorphism of microsatellite loci suggests that Japanese populations are indigenous or were introduced a very long time ago. We discuss differences in invasion patterns between the Ryukyu Islands and the Ogasawara Islands. PMID:26513585

  20. Genetic Differentiation and Spatial Structure of Phellinus noxius, the Causal Agent of Brown Root Rot of Woody Plants in Japan.

    Directory of Open Access Journals (Sweden)

    Mitsuteru Akiba

    Full Text Available Phellinus noxius is a pathogenic fungus that causes brown root rot disease in a variety of tree species. This fungus is distributed in tropical and sub-tropical regions of Southeast and East Asia, Oceania, Australia, Central America and Africa. In Japan, it was first discovered on Ishigaki Island in Okinawa Prefecture in 1988; since then, it has been found on several of the Ryukyu Islands. Recently, this fungus was identified from the Ogasawara (Bonin Islands, where it has killed trees, including rare endemic tree species. For effective control or quarantine methods, it is important to clarify whether the Japanese populations of P. noxius are indigenous to the area or if they have been introduced from other areas. We developed 20 microsatellite markers from genome assembly of P. noxius and genotyped 128 isolates from 12 of the Ryukyu Islands and 3 of the Ogasawara Islands. All isolates had unique genotypes, indicating that basidiospore infection is a primary dissemination method for the formation of new disease foci. Genetic structure analyses strongly supported genetic differentiation between the Ryukyu populations and the Ogasawara populations of P. noxius. High polymorphism of microsatellite loci suggests that Japanese populations are indigenous or were introduced a very long time ago. We discuss differences in invasion patterns between the Ryukyu Islands and the Ogasawara Islands.

  1. Improvement of Biocontrol of Damping-off and Root Rot/Wilt of Faba Bean by Salicylic Acid and Hydrogen Peroxide

    OpenAIRE

    Montaser Fawzy ABDEL-MONAIM

    2013-01-01

    Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogen...

  2. FcStuA from Fusarium culmorum controls wheat foot and root rot in a toxin dispensable manner.

    Science.gov (United States)

    Pasquali, Matias; Spanu, Francesca; Scherm, Barbara; Balmas, Virgilio; Hoffmann, Lucien; Hammond-Kosack, Kim E; Beyer, Marco; Migheli, Quirico

    2013-01-01

    Fusarium culmorum is one of the most harmful pathogens of durum wheat and is the causal agent of foot and root rot (FRR) disease. F. culmorum produces the mycotoxin deoxynivalenol (DON) that is involved in the pathogenic process. The role of the gene FcStuA, a StuA ortholog protein with an APSES domain sharing 98.5% homology to the FgStuA protein (FGSG10129), was determined by functional characterisation of deletion mutants obtained from two F. culmorum wild-type strains, FcUk99 (a highly pathogenic DON producer) and Fc233B (unable to produce toxin and with a mild pathogenic behavior). The ΔFcStuA mutants originating from both strains showed common phenotypic characters including stunted vegetative growth, loss of hydrophobicity of the mycelium, altered pigmentation, decreased activity of polygalacturonic enzymes and catalases, altered and reduced conidiation, delayed conidial germination patterns and complete loss of pathogenicity towards wheat stem base/root tissue. Glycolytic process efficiency [measured as growth on glucose as sole carbon (C) source] was strongly impaired and growth was partially restored on glutamic acid. Growth on pectin-like sources ranked in between glucose and glutamic acid with the following order (the lowest to the highest growth): beechwood xylan, sugarbeet arabinan, polygalacturonic acid, citrus pectin, apple pectin, potato azogalactan. DON production in the mutants originating from FcUK99 strain was significantly decreased (-95%) in vitro. Moreover, both sets of mutants were unable to colonise non-cereal plant tissues, i.e. apple and tomato fruits and potato tubers. No differences between mutants, ectopic and wild-type strains were observed concerning the level of resistance towards four fungicides belonging to three classes, the demethylase inhibitors epoxiconazole and tebuconzole, the succinate dehydrogenase inhibitor isopyrazam and the cytochrome bc1 inhibitor trifloxystrobin. StuA, given its multiple functions in cell regulation

  3. First Report of Sclerotinia Rot Caused by Sclerotinia nivalis on Panax ginseng in Korea

    OpenAIRE

    Hye Sun Cho; Jeong-Sup Shin; Jae-Hyun Kim; Tae-Kyun Hong; Dae-Hui Cho; Je Yong Kang

    2013-01-01

    Sclerotinia rot disease was observed on 5 and 6-year-old ginseng (Panax ginseng) roots in Hongchun, Cheorwon, and Yanggu, Gangwon Province, Korea from 2006 to 2010. Symptoms included a brownish watery soft rot of the roots, and black sclerotia were often found on the rotten roots. The causal agent of the disease was identified as Sclerotinia nivalis based on cultural characteristics and sequence analyses of the internal transcribed spacer region of rDNA and β-tubulin gene with 100% sequence s...

  4. CHANGES IN THE BIOCHEMICAL CONSTITUENTS OF CARROT ROOTS DUE TO BACTERIAL SOFT ROT

    OpenAIRE

    V. K. Parthiban; V. Prakasam; Prabakar, K.

    2013-01-01

    Carrot is a rich source of nutrients. The carrot contains carotene and lycopene, which gives bright color to the roots. The quality of the carrots was assessed based on the carotene, lycopene and other biochemical constituents like sugars, starch and protein. To study the effect of various isolates of the Erwinia carotovora var. carotovora on the above biochemical constituents, the pathogens were inoculated and the contents were analyzed separately at 1, 2, 3, 4, 5 days after inoculation. The...

  5. Soil-borne pathogens in intensive legume cropping - Aphanomyces spp. and root rots

    OpenAIRE

    Levenfors, Jens

    2003-01-01

    Root diseases caused by soil-borne pathogens are often main constraints in legume crop production. Changes towards organic farming practices have recently contributed to an increase in legume cropping, mainly for nitrogen supply purposes, and these have raised concerns about unacceptable build-up of soil-borne pathogen inocula. This study aimed to evaluate the impact of frequent legume cropping on such inocula build-up, and had emphasis on Aphanomyces euteiches, an important pathogen causing ...

  6. Seed priming with extracts of Acacia nilotica (L.) Willd. ex Delile and Sapindus mukorossi (L.) plant parts in the control of root rot fungi and growth of plants

    International Nuclear Information System (INIS)

    Seed priming with plant extracts and chemicals has been used as an important growth enhancement tool in crop plants. In this research, an attempt was made to understand the mechanism of various seed priming treatments on greenhouse-grown okra (Abelmoschus esculentus (L.) Moench.), sunflower (Helianthus annuus L.), peanut (Arachis hypogaea L.) and chickpea (Cicer arietinum L.) for the control of root infecting fungi like Rhizoctonia solani (Kn), Fusarium spp. and Macrophomina phaseolina (Tassi) Goid by plant parts extracts (stem, leaves and seeds) of Acacia nilotica (L.) Willd. ex Delile and Sapindus mukorossi (L) at different time intervals (5, 10, 20, 40 minutes). Results showed significant suppression of root rot fungi and significantly enhanced the growth parameters like shoot length, root length, shoot weight and root weight. Seed-priming with A. nilotica and S. mukorossi leaves extract for 10 minutes time interval was found to be effective for the control of root rot fungi and growth of all tested leguminous and non-leguminous plants. (author)

  7. CHANGES IN THE BIOCHEMICAL CONSTITUENTS OF CARROT ROOTS DUE TO BACTERIAL SOFT ROT

    Directory of Open Access Journals (Sweden)

    V. K. Parthiban

    2013-03-01

    Full Text Available Carrot is a rich source of nutrients. The carrot contains carotene and lycopene, which gives bright color to the roots. The quality of the carrots was assessed based on the carotene, lycopene and other biochemical constituents like sugars, starch and protein. To study the effect of various isolates of the Erwinia carotovora var. carotovora on the above biochemical constituents, the pathogens were inoculated and the contents were analyzed separately at 1, 2, 3, 4, 5 days after inoculation. The contents of β-carotene increased significantly due to all the three isolates of the pathogen and the Coimbatore isolate recorded highest of 36.03 per cent. A same trend was also observed in the lycopene content with 93.55 per cent increase over control. The contents of total and reducing sugars were found to significantly increase due to inoculation with the pathogen. The starch content showed a decreasing trend in all the isolates tested. The maximum reduction of 62.98 per cent was observed in the roots inoculated with Coimbatore isolate.

  8. Soil amendment with Aerva javanica (Burm. F.) Juss. ex Schult. in the control of root rot fungi of cowpea [Vigna unguiculata (L.) Walp.] and mung bean [Vigna radiata (L.)

    OpenAIRE

    Naheed Ikram; Shahnaz Dawar

    2012-01-01

    Root rot fungi cause severe losses of crop plants, so the present work was carried out to determine the effect of Aerva javanica parts powder on root infecting fungi of mung bean (Vigna radiata (L.) and cowpea (Vigna unguiculata (L.) Walp.). A. javanica parts (stem, leaves and flower) were used as soil amendments at 0.1, 1 and 5% to check the effectiveness on growth parameters. All the plant parts showed a significant reduction in root rot fungi like Fusarium spp., Rhizoctonia solani Kuhn, an...

  9. Improvement of Biocontrol of Damping-off and Root Rot/Wilt of Faba Bean by Salicylic Acid and Hydrogen Peroxide.

    Science.gov (United States)

    Abdel-Monaim, Montaser Fawzy

    2013-03-01

    Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride and Bacillus megaterium) and chemical inducers (salicylic acid [SA] and hydrogen peroxide) individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promoting of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi. Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA + B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/wilt severity and increased of survival plants. Also, these treatments increased fresh and weights of the survival plants in pots compared with control. The combination between biocontrol agents and chemical inducers were more effective than used of them individually and SA + T. viride was the best treatment in this respect. Also, under field conditions, all these treatments significantly increased growth parameters (plant height and number of branches per plant) and yield components (number of pods per plant and number of seeds per plant, weight of 100 seeds and total yield per feddan) and protein content in both seasons (2010~2011 and 2011~2012). Faba bean seeds soaked in SA + T. viride and SA + B. megaterium were recorded the highest growth parameters and yield components. Generally, the

  10. Effect of inoculum density and soil tillage on the development and severity of rhizoctonia root rot.

    Science.gov (United States)

    Schroeder, K L; Paulitz, T C

    2008-03-01

    Rhizoctonia spp. cause substantial yield losses in direct-seeded cereal crops compared with conventional tillage. To investigate the mechanisms behind this increased disease, soils from tilled or direct-seeded fields were inoculated with Rhizoctonia spp. at population densities from 0.8 to 250 propagules per gram and planted with barley (Hordeum vulgare). The incidence and severity of disease did not differ between soils with different tillage histories. Both R. solani AG-8 and R. oryzae stunted plants at high inoculum densities, with the latter causing pre-emergence damping-off. High inoculum densities of both species stimulated early production of crown roots in barley seedlings. Intact soil cores from these same tilled and direct-seeded fields were used to evaluate the growth of Rhizoctonia spp. from colonized oat seeds. Growth of R. oryzae was not affected by previous tillage history. However, R. solani AG-8 grew more rapidly through soil from a long-term direct-seeded field compared to tilled soils. The differential response between these two experiments (mixed, homogenized soil versus intact soil) suggests that soil structure plays a major role in the proliferation of R. solani AG-8 through soils with different tillage histories. PMID:18944081

  11. FcStuA from Fusarium culmorum controls wheat foot and root rot in a toxin dispensable manner.

    Directory of Open Access Journals (Sweden)

    Matias Pasquali

    Full Text Available Fusarium culmorum is one of the most harmful pathogens of durum wheat and is the causal agent of foot and root rot (FRR disease. F. culmorum produces the mycotoxin deoxynivalenol (DON that is involved in the pathogenic process. The role of the gene FcStuA, a StuA ortholog protein with an APSES domain sharing 98.5% homology to the FgStuA protein (FGSG10129, was determined by functional characterisation of deletion mutants obtained from two F. culmorum wild-type strains, FcUk99 (a highly pathogenic DON producer and Fc233B (unable to produce toxin and with a mild pathogenic behavior. The ΔFcStuA mutants originating from both strains showed common phenotypic characters including stunted vegetative growth, loss of hydrophobicity of the mycelium, altered pigmentation, decreased activity of polygalacturonic enzymes and catalases, altered and reduced conidiation, delayed conidial germination patterns and complete loss of pathogenicity towards wheat stem base/root tissue. Glycolytic process efficiency [measured as growth on glucose as sole carbon (C source] was strongly impaired and growth was partially restored on glutamic acid. Growth on pectin-like sources ranked in between glucose and glutamic acid with the following order (the lowest to the highest growth: beechwood xylan, sugarbeet arabinan, polygalacturonic acid, citrus pectin, apple pectin, potato azogalactan. DON production in the mutants originating from FcUK99 strain was significantly decreased (-95% in vitro. Moreover, both sets of mutants were unable to colonise non-cereal plant tissues, i.e. apple and tomato fruits and potato tubers. No differences between mutants, ectopic and wild-type strains were observed concerning the level of resistance towards four fungicides belonging to three classes, the demethylase inhibitors epoxiconazole and tebuconzole, the succinate dehydrogenase inhibitor isopyrazam and the cytochrome bc1 inhibitor trifloxystrobin. StuA, given its multiple functions in cell

  12. Disease Investigation and Identification of the Pathogens Causing Root Rot of Tussilago farfaral%款冬花根腐病的发病情况与病原鉴定

    Institute of Scientific and Technical Information of China (English)

    张爱香; 马海莲; 李雪萍; 仝在利; 李世东; 王晓涛

    2011-01-01

    为找出引起款冬花根腐病的主要病原,对其综合防治提供参考依据,通过田间调查款冬花根腐病的症状以及室内病原物的分离、培养、纯化、回接试验.结果表明:款冬花根腐病的症状主要是萎蔫和根腐,引起根腐病的病原主要是立枯丝核菌(Rhizoctonia solani)、灰葡萄孢菌(Botrytis cinerea)、尖孢镰孢菌(Fusarium oxysporum Schlecht).%Symptom of Tussilago far faral root rot was investigated in the field and pathogens of Tussilago farfaral root rot was isolated, cultured, purified and re-inoculated in the laboratory to find out the main pathogens causing root rot of Tussilago farfaral and provide a reference for its comprehensive control. The results showed that the symptoms of the disease were expressed as wilt and root rot. Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum were the major pathogens of Tussilago far faral root rot.

  13. Integrated Management of Damping-off, Root and/or Stem Rot Diseases of Chickpea and Efficacy of the Suggested Formula

    Directory of Open Access Journals (Sweden)

    Montaser Fawzy ABDEL-MONAIM

    2011-08-01

    Full Text Available Eleven fungal isolates were isolated from naturally infected chickpea roots collected from different locations in New Valley Governorate (Egypt. The isolated fungi were purified and identified as Rhizoctonia solani (5 isolates, Fusarium solani (4 isolates and Sclerotinia sclerotiorum (2 isolates. The isolated fungi proved their pathogenicity on cv. �Giza 3�. Response of chickpea cvs. �Giza 1�, �Giza 2�, �Giza 3�, �Giza 4�, �Giza 88�, �Giza 195�, �Giza 531� to infection by the tested fungi was significantly varied. �Giza 1� was the most resistant one followed by �Giza 531�, while the other tested cvs. were highly susceptible. Seven biocontrol agents, namely Bacillus subtilis, B. megaterium, B. cereus, Trichoderma viride, T. harzianum, Aspergillus sp., Penicillium sp. isolated from chickpea rhizosphere, were tested for their antagonistic action against the tested pathogens. B. subtilis isolate BSM1, B. megaterium isolate TVM5, T. viride isolate TVM2 and T. harzianum isolate THM4 were the most antagonistic ones to the tested fungi in vitro, while the other isolates were moderate or weak antagonists. The most antagonistic isolates as well as the commercial biocide Rhizo-N were applied as seed treatment for controlling damping-off, root and/or stem rot diseases caused by the tested fungi under greenhouse conditions. The obtained data showed that all tested antagonistic isolates were able to cause significant reduction of damping-off, root and/or stem rot diseases in chickpea plants. T. viride (isolate TVM2 and B. megaterium (isolate BMM5 proved to be the most effective isolates for controlling the diseases. Under field condition, the obtained data indicated that all the tested antagonistic isolates significantly reduced damping-off, root and/or stem rot. T. viride (isolate TVM2 and B. megaterium (isolate BMM5 recorded the highest reduction of damping-off, root and/or stem rot in all sowing dates. Sowing of

  14. Modeling Lolium perenne L. roots in the presence of empirical black holes

    Science.gov (United States)

    Plant root models are designed for understanding structural or functional aspects of root systems. When a process is not thoroughly understood, a black box object is used. However, when a process exists but empirical data do not indicate its existence, you have a black hole. The object of this re...

  15. EFFECT OF SHADING ON INCIDENCE OF BLACK ROT DISEASE AND YIELD QUALITY OF BROCCOLI IN HUMID TROPICAL REGIONS OF THAILAND

    Directory of Open Access Journals (Sweden)

    Karistsapol Nooprom

    2013-08-01

    Full Text Available The study was carried out in the experimental location of Department of Plant Science, Faculty of Natural Resources, Prince of Songkla University, Thailand, from April to June, 2012. Split-plot in randomized complete block design was used in this experiment with four replications. The broccoli plants under the shading had the lowest incidence of black rot disease (14.48% which was significantly lower than the full sunlight (76.91%. There was a positive impact of the shading on yield quality of the broccoli. The Yok Kheo had the highest head length and diameter (39.13 cm and 12.11 cm, respectively when planting under the shading. These results consistent with broccoli total yield, the highest total yield was obtained from the Yok Kheo under the both shading and full sunlight (10.92 t.ha-1 and 8.29 t.ha-1, respectively, followed by the Green Queen under the shading (6.21 t.ha-1. Therefore, the appropriate variety for planting during dry season in humid tropical regions of Thailand was the Yok Kheo and Green Queen because its total yield per hectare was higher than of the Top Green and they also had higher quality of head.

  16. Effect of Lobesia botrana damages on black aspergilli rot and ochratoxin A content in grapes.

    Science.gov (United States)

    Cozzi, G; Pascale, M; Perrone, G; Visconti, A; Logrieco, A

    2006-09-01

    Sixty-nine wine grape samples of two varieties (Bombino Nero and Uva di Troia) were collected from four vineyards in a high ochratoxin A (OTA) incidence grape-growing area in Apulia, southern Italy, during the 2001 and 2002 crop harvests. The levels of toxin, measured in the two year harvests, ranged from 0.02 to 681 ng/g of fresh berries. In both surveys, higher levels of contamination by black aspergilli and OTA were found in both intact and rotten berries originating from bunches damaged by Lobesia botrana larvae as compared to bunches without L. botrana attacks. All berry samples with an OTA level >1 ng/g were contaminated by black aspergilli with a CFU>10(6), and all but one of these samples belonged to the Lobesia damaged berries group. This is the first evidence of an interaction between L. botrana damaged berries and OTA contamination, in field. PMID:16707181

  17. Microbial Properties of Composts That Suppress Damping-Off and Root Rot of Creeping Bentgrass Caused by Pythium graminicola.

    Science.gov (United States)

    Craft, C M; Nelson, E B

    1996-05-01

    pressure was high (i.e., disease ratings high in uninoculated plots). A 1991 batch of turkey litter compost and the 1990 batch of Endicott biosolids were consistently suppressive to foliar symptoms of Pythium root rot on creeping bentgrass. This study indicates that suppression of Pythium diseases of creeping bentgrass in batches of brewery sludge and Endicott biosolids composts, and possibly in other suppressive composts examined in less detail in this study, is related directly to the microbial activities in the composts. On the other hand, the mechanisms of Pythium suppression in turkey litter and perhaps other poultry-based composts is not related directly to the compost microbial activity. Although turkey litter showed a lack of suppressiveness in laboratory bioassays and low microbial populations and activity, it resulted in a significant and consistent level of suppressiveness in field experiments. Therefore, the microbiological properties of Pythium-suppressive composts may differ substantially, and measurements of microbial populations and activity may not be predictive of the level of disease suppression in all composts. PMID:16535307

  18. Nutrient Dynamics of Fine Roots in the Mixed Plantation of Poplar and Black Locust

    Institute of Scientific and Technical Information of China (English)

    Zhai Mingpu; Jiang Sannai; Jia Liming

    2006-01-01

    The mixed plantation of poplar (Populus spp.)and black locust (Robinia pseudoacacia) is one of the typical mixed stands with nitrogen-fixing and non-nitrogen-fixing species.Interaction between the two species in the mixed stand is harmonious and productivity is high,making this kind of mixed plantation a very successful pattern on poor sandy sites in north China.In this study,the fine root decomposition of the two species was investigated in the mixed plantation of 27-year-old Canadian poplar (P.canadansis)and 22-year-old black locust on sandy sites along the Chaobai River in Beijing.Mechanism of harmonious interaction between the two species was observed in the view of the nutrient cycle of fine roots.Results showed that:(1) the fine root decomposition of Canadian poplar and black locust trees was different.Concentrations of N,Ca and Mg gradually increased and those of P and K gradually decreased in the fine roots of poplar during the period of decomposition.Concentrations of N,P and K gradually decreased in the fine roots of black locust during decomposition.The speed of nutrient decomposition in mixed fine roots of the two species fell between the speed of the two pure samples.(2) During decomposition,the annual return amount of N,K and Mg in fine roots of black locust was highest,followed by the mixed fine roots of the two species,and then the fine roots of poplar.(3) The increased return amount of N in mixed fine roots could improve the N nutrient condition of poplar trees.The return amount of P in poplar Fine roots was greater than that of black locust,which could improve the P nutrient of black locust trees.The interaction of mutual supplements of N and P nutrient cycle of fine roots between these two species formed.

  19. The influence of soil moisture and Rhizoctonia solani anastomosis and intraspecific group on the incidence of damping-off and the incidence and severity of Rhizoctonia crown and root rot in sugar beet

    Science.gov (United States)

    Rhizoctonia crown and root rot (Rhizoctonia solani) reduces plant stands, sugar quality and yield in sugar beet. To evaluate the influence of R. solani anastomosis (AG) and intraspecific groups and soil moisture on disease incidence and severity, a field trial was established in Ridgetown, Ontario, ...

  20. Comparative effect of partial root-zone drying and deficit irrigation on incidence of blossom-end rot in tomato under varied calcium rates

    DEFF Research Database (Denmark)

    Sun, Yanqi; Feng, Hao; Liu, Fulai

    2013-01-01

    xylem sap abscisic acid concentration, lower stomatal conductance, and higher plant water status in the PRD in relation to the DI plants might have contributed to the increased fruit Ca uptake, and could have reduced BER development in tomato fruits. Therefore, under conditions with limited freshwater...... resources, application of PRD irrigation could be a promising approach for saving water and for preventing BER development in tomatoes.......This study investigated the comparative effects of reduced irrigation regimes—partial root-zone drying (PRD) and conventional deficit irrigation (DI)—on the incidence of blossom-end rot (BER) in tomato (Solanum lycopersicum L.) under three Ca-fertilization rates: 0, 100, and 200mg Ca kg–1 soil...

  1. Determination of the Effects of Nutrient sources on Enhancement of Crop Tolerance to Bean Root Rot and Bean Stem Maggot in Western Kenya

    International Nuclear Information System (INIS)

    Field bean phaseolus vulgaris tolerance to root rot (BRR) and bean stem maggot (BSM) is enhanced by improvement of soil nutrients. Organic and inorganic sources of soil nutrients were evaluated in this study to determine their effects on crop tolerance to BRR and BSM. Three variety of GLP 585 susceptible to BRR and BSM; GLP X92 tolerant to BRR and BSM; and KK-8 resistant to BRR and BSM were used. The study was conducted in farmer's field with high level of BRR and BSM over three seasons in a split plot design. Nutrient sources were laid down in main plots while varieties were in subplots. KK-8 gave the highest plant survival and yield over the seasons. GLP 585 had the lowest mean yield and plant survival. Crop tolerance was greatly improved by application of DAP as applied as nutrient sources and varieties for crop tolerance were identified

  2. Biological Control of Fusarium oxysporum f. sp. melonis, the Causal Agent of Root Rot Disease of Greenhouse Cucurbits in Kerman Province of Iran

    Directory of Open Access Journals (Sweden)

    Sara Shafii Bafti

    2005-01-01

    Full Text Available Antagonistic activity of 178 soil actinomycete isolates was assayed against Fusarium oxysporum f. sp. melonis Schlecht, Emend (Snyde and Hansen cause of root rot and fusarium wilt of greenhouse cucurbits in Kerman Province, southeast of Iran. From tested isolates, Streptomyces olivaceus (strain 115 showed anti-fusarium activity revealed through screening and bioassays by agar disk and well-diffusion methods. The active strain was grown in submerged cultures for determination of growth curve and preparation of crude extract for further biological characterizations. Antifungal activity was fungistatic type on the pathogen mycelia. It is prominent that amending greenhouse soil mix with the S. olivaceus (strain 115 will reduce crop losses by the pathogen.

  3. Antagonism of local isolates of Trichoderna spp.on citrus root rot disease by Fusarium solani in the mekong delta of vietnam

    Institute of Scientific and Technical Information of China (English)

    Duong Minh; Jozef Coosemans; Le Lam Cuong; Ester Vandersmissen; Pham Van Kim

    2004-01-01

    @@ The local isolates of Trichoderrma spp. and Fusariun solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch's postulate testing. The results showed that the high chitinolytic enzymes content of Trichoderma isolates can antagonise with Fusarium solani isolates by preventing the germination of Fusarium macroconidia in in-vitro condition. There are five promising isolates of Trichoderna spp. having high antagonism with Fusarium solani. These Trichoderma isolates also grew well in rice straws, maize stems, weeds and water hyacinth biowaste materials. These results supply the promising trend for biological control of root rot disease on citrus orchards of the Mekong delta.

  4. WEED PLANTS OF THE FAMILY POACEAE AS SOURCES OF INFECTION OF WINTER WHEAT ROOT ROT Сорные растения семейства poaceae как источники инфекции корневых гнилей озимой пшеницы

    Directory of Open Access Journals (Sweden)

    Shutko A. P.

    2013-01-01

    Full Text Available In the article, there are the data of a specific variety of cereal weed plants in crops of winter wheat on a black leached soil depending on the predecessor and the way of processing of a soil and its role as a source of an infection root rot. The greatest number of isolates of mushrooms – causative agents of a disease, was allocated from such weed plants as wheat grass creeping, eras galli, field (chess brome grass; the smallest – from Lolium temulentum. Fusariosis root decay dominates in community of cereal weed plants

  5. Biocontrol de la pudrición de raíz de nochebuena de interior con Trichoderma spp. Root rot biocontrol for indoor poinsettia with Trichoderma spp.

    Directory of Open Access Journals (Sweden)

    Felipe de Jesús Osuna-Canizalez

    2012-06-01

    Full Text Available En Morelos, la pudrición de la raíz causada por Fusarium spp., es una de las principales enfermedades de la nochebuena de interior. Por su efecto devastador, en su prevención o control se realizan aplicaciones frecuentes de productos químicos, con los riesgos inherentes a la salud humana y al ambiente. En la búsqueda de alternativas bioracionales al manejo de esta enfermedad, se realizó un ensayo en el que se evaluaron tres cepas comerciales de Trichoderma spp., en tres diferentes sustratos: S1= "tierra de hoja" (70% v/v+tezontle grueso (15% v/v+tezontle fino (10% v/v+agrolita (5% v/v; S2= turba (80% v/v+ fibra de coco (20% v/v; S3= "tierra de hoja" (70% + "tepojal" (30%, en las variedades comerciales más comunes, Freedom Red y Prestige Red. Se utilizó un diseño factorial de tratamientos 4 x 3 x 2 y los tratamientos resultantes se evaluaron en un diseño completamente al azar con seis repeticiones. Respecto a la incidencia de pudrición de la raíz, las cepas comerciales de Trichoderma spp., no mostraron diferencias entre sí ni con el testigo químico. La pudrición de la raíz estuvo asociada con S2, debido a una baja capacidad de aireación, y sólo se presentó en Prestige Red. La población (UFC g-¹ de Trichoderma spp., en el sustrato al término del ciclo, fue igual (pIn Morelos, root rot caused by Fusarium spp., is one of the main diseases of indoor poinsettia. In order to prevent or control its devastating effect, frequent applications of chemical products are performed, with inherent risks to human health and environment. In quest for alternative biorational options, an essay in which three commercial strains of Trichoderma spp., was done, in three different substrates: S1= "organic soil" (70% v/v+thick tezontle (15% v/v+thin tezontle (10% v/v+agrolita (5% v/v; S2= peat moss (80% v/v+ coconut fiber (20% v/v; S3= "organic soil" (70%+"tepojal" (30%, in most common commercial varieties, Freedom Red and Prestige Red. A factorial

  6. Effect of Bio-Control Agents on Yield, Yield Components and Root Rot Control in two Wheat Cultivars at New Valley Region

    Directory of Open Access Journals (Sweden)

    Mohamed Yosseif MOUBARK

    2011-11-01

    Full Text Available This study evaluated the effectiveness of applying the bioagents Bacillus subtilis (isolate BSM1, B. megaterium (isolate BMM5, Trichoderma viride (isolate TVM2 and T. harzianum (isolate THM4 for the control of rot root disease caused by Fusarium graminearum, Drechslera halodes and Rhizoctonia solani on two wheat cultivars (�Sakha 93� and �Bani Suif 5� under greenhouse conditions. Moreover, their effect wheat growth and yield were also studied under field conditions. In vitro, all tested bioagents were significantly in the reduced redial growth of the pathogenic fungi. Trichoderma viride was active more than the other tested bioagents followed by T. harzianum, while B. subtilis was the least ones. Under greenhouse conditions, all tested bioagents were able to reduce significantly damping-off and root rot caused by the tested pathogens compared with control and increased fresh and dry weight of the survival plants when applied as soil or grain treatments however, there was variation among bioagent isolates effect on reduction of disease severity both application methods. Trichoderma viride and B. megaterium were recorded the highest effective in this respect compared with other tested bioagents. Under field conditions, analysis of variance and mean performance were estimated for four characters: grain yield 4.8 m-2, No. of spikes m-2, No. of kernels spike-1 and 1000-kernel weight. Significant mean squares were obtained for all studied characters between the seasons (S, methods (M, (S (M, treatments (T, (S (T, (M (T and (S (M (T for �Sakha 93� cultivar and �Bani Suif 5� cultivars except application methods and (S (M for number of kernels spike-1 and 1000-kernel weight, respectively. While the treatments T. harzianum and B. megaterium were best treatments to increase grain yield, the treatments B. subtilis and T. harzianum were best treatments to increase number of spikes and the treatments B. subtilis and B. megaterium were best

  7. Decolourization potential of white-rot fungus Phanerochaete chrysosporium on synthetic dye bath effluent containing Amido black 10B

    OpenAIRE

    Senthilkumar, S.; M. Perumalsamy; H. Janardhana Prabhu

    2014-01-01

    Synthetic azo dyes are extensively used in textile industry and are not easily degraded into the environment due to their complex structure. Due to the low degree of fixation of these dyes to fabrics, more than 10–15% of the dye does not bind to fabrics during colour processing and release into water bodies as effluent cause serious environmental pollution. White-rot fungus is found to be capable of degrading lignin which has a complex structure similar to azo dyes. In this study, the decolou...

  8. Trichoderma spp. decrease Fusarium root rot in common bean Trichoderma spp. reduzem a podridão-radicular de Fusário em feijoeiro comum

    Directory of Open Access Journals (Sweden)

    Hudson Teixeira

    2012-12-01

    Full Text Available The effectiveness of six Trichoderma-based commercial products (TCP in controlling Fusarium root rot (FRR in common bean was assessed under field conditions. Three TCP, used for seed treatment or applied in the furrow, increased seedling emergence as much as the fungicide fludioxonil. FRR incidence was not affected, but all TCP and fludioxonil reduced the disease severity, compared to control. Application of Trichoderma-based products was as effective as that of fludioxonil in FRR management.A eficácia de seis produtos comerciais à base de Trichoderma (PCT no controle da podridão-radicular-seca do feijoeiro (PRS foi avaliada em condições de campo. Três PCT, usados no tratamento de sementes ou aplicados no sulco de plantio, aumentaram a emergência das plântulas tanto quanto o fungicida fludioxonil. A incidência de PRS não foi afetada, mas todos os PCT e o fludioxonil reduziram a severidade em relação à testemunha. A aplicação de produtos à base de Trichoderma spp. foi tão eficaz quanto o fludioxonil no manejo da PRS.

  9. In-Vitro Evaluation of Fungicides and Fungicide Combinations Against Fusarium Root-Rot Fungal Pathogens of French Beans(Phaseolus Vulgaris L. c v. Monel

    International Nuclear Information System (INIS)

    Laboratories studies were undertaken to evaluate In-vitro efficacy of captan, thiram, pyrazophos, triforine and metalaxyl + mancozeb fungicides against Fusarium solani (Mart.) Appel and Wollenw fsp. phaseoli (Burk) Synder and Hansen Fusarium oxysporum Schlecht fsp. phaseoli kend and Synder root-rot fungal pathogens of French beans. Five fungicides and four combinations were tested for their antifungal activity. Fungicides treatments significantly (P=0.05) inhibited mycelial growth and spore germination. Fungicides suppressed the growth of F. oxysporum fsp. Phaseoli more than that of F. solani fsp. phaseoli. All fungicides except metalaxyl + mancozeb failed to suppress sporulation of the two fungi In-vitro. In the case of thiram the sporulation capacity of F. oxysporum fsp. phaseoli 3.43 times higher than in the control. Although, no fungicides treatment was seen to inhibitor of all the three measures of fungitoxicity, the ranking of the best three fungicide treatments would be, thiram 50 + captan so > triforine > metalaxyl + mancozeb. The relatively higher inhibitory effect of fungicides on the growth of F. oxysporum Ssp. Phaseoli than that of F. solani fsp. Phaseoli suggested that F. oxysporum Esp. Phaseoli was more sensible to fungicide treatments. Such differences may reflect inherent variations in accessibility of the active toxicants within the fungal systems. The ability attributed to the low growth rate, N depletion temperature and oxygen

  10. Genome sequences of two Phytophthora species responsible for Sudden Oak Death and Soybean Root Rot provide novel insights into their evolutionary origins and mechanisms of pathogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, Brett M.; Tripathi, Sucheta; Aerts, Andrea; Bensasson, Douda; Dehal, Paramvir; Dubchak, Inna; Garbelotto, Matteo; Gijzen, Mark; Huang, Wayne; Ivors, Kelly; Jiang, Rays; Kamoun, Sophien; Krampis, Konstantinos; Lamour, Kurt; McDonald, Hayes; Medina, Monica; Morris, Paul; Putnam, Nik; Rash, Sam; Salamov, Asaf; Smith, Brian; Smith, Joe; Terry, Astrid; Torto, Trudy; Grigoriev, Igor; Rokhsar, Daniel; Boore, Jeffrey

    2005-12-01

    The approximately 60 species of Phytophthora are all destructive pathogens, causing rots of roots, stems, leaves and fruits of a wide range of agriculturally and ornamentally important plants (1). Some species, such as P. cinnamomi, P. parasitica and P. cactorum, each attack hundreds of different plant host species, whereas others are more restricted. Some of the crops where Phytophthora infections cause the greatest financial losses include potato, soybean, tomato, alfalfa, tobacco, peppers, cucurbits, pineapple, strawberry, raspberry and a wide range of perennial tree crops, especially citrus, avocado, almonds, walnuts, apples and cocoa, and they also heavily affect the ornamental, nursery and forestry industries. The economic damage overall to crops in the United States by Phytophthora species is estimated in the tens of billions of dollars, including the costs of control measures, and worldwide it is many times this amount (1). In the northern midwest of the U.S., P. sojae causes $200 million in annual losses to soybean alone, and worldwide causes around $1-2 billion in losses per year. P. infestans infections resulted in the Irish potato famine last century and continues to be a difficult and worsening problem for potato and tomato growers worldwide, with worldwide costs estimated at $5 billion per year.

  11. Reaction of arracacha genotypes to the root soft rot caused by Pectobacterium chrysanthemi Reação de genótipos de mandioquinha-salsa à podridão-mole das raízes causada por Pectobacterium chrysanthemi

    OpenAIRE

    Gilmar Paulo Henz; Francisco José Becker Reifschneider; Fausto Francisco dos Santos

    2005-01-01

    The purpose of this paper was to screen thirty-two arracacha genotypes for their reaction to root soft rot. Twenty roots of each genotype were inoculated with two Pectobacterium chrysanthemi isolates in a randomized experiment (10 roots/isolate). After inoculation, roots were individually wrapped with PVC film and kept at 26ºC in closed plastic bags. Soft rot lesions were recorded after 36 hours and genotypes were grouped in four classes of susceptibility by cluster analysis: 10 were less sus...

  12. Reação de cultivares de abacateiro à podridão de raízes Reaction of avocado cultivars to avocado root rot

    Directory of Open Access Journals (Sweden)

    Ciro Hideki Sumida

    2009-07-01

    Full Text Available As cultivares de abacateiro (Persea americana Mill 'Margarida', 'Fortuna' e 'Hass' têm muita importância econômica no mercado nacional e internacional. Em função disso, este trabalho teve como objetivo avaliar a reação dessas cultivares frente à Phytophthora cinnamomi Rands., agente causal da podridão das raízes. A inoculação do patógeno foi feita por meio de implantação de tecidos de raízes sintomáticas. Foram inoculadas quatro raízes em três árvores diferentes, uma de cada cultivar, em três pontos diferentes da raiz. Em cada cultivar, das quatro raízes, uma foi utilizada como testemunha, nas quais foram implantados tecidos sadios. A avaliação foi realizada aos 120 dias após a inoculação, observando-se as raízes externamente quanto à alteração da coloração e presença de estruturas de patógenos na região da superfície da casca nos pontos inoculados. Internamente, foram removidas as cascas para visualização das alterações a partir do ponto inoculado, sendo observadas alterações de coloração dos tecidos e realizada mensuração da extensão do escurecimento (lesão aparente. Nas extremidades das lesões foram retirados segmentos de raízes e implantados em meio de cultivo farinha de milho-ágar e incubados, para verificação da colonização na área sem escurecimento, ou seja, a colonização não- aparente. Das cultivares avaliadas, a 'Hass' foi a menos suscetível ao P. cinnamomi, quando comparada às cultivares 'Fortuna' e 'Margarida'. O patógeno P. cinnamomi pode apresentar desenvolvimento ou colonização nos tecidos radiculares além da área sintomática.Cultivars of the avocado (Persea americana Mill 'Margarida', 'Fortuna' and 'Geada' have importance in the national and international markets. The present paper had as objective to evaluate the reaction of such cultivars to Phytophthora cinanamomi Rands, the causal agent of avocado root rot. They were inoculated four roots in three different

  13. Decolourization potential of white-rot fungus Phanerochaete chrysosporium on synthetic dye bath effluent containing Amido black 10B

    Directory of Open Access Journals (Sweden)

    S. Senthilkumar

    2014-12-01

    Full Text Available Synthetic azo dyes are extensively used in textile industry and are not easily degraded into the environment due to their complex structure. Due to the low degree of fixation of these dyes to fabrics, more than 10–15% of the dye does not bind to fabrics during colour processing and release into water bodies as effluent cause serious environmental pollution. White-rot fungus is found to be capable of degrading lignin which has a complex structure similar to azo dyes. In this study, the decolourization potential of white-rot fungus Phanerochaete chrysosporium, which is capable of decolourizing synthetic dye bath effluent, was investigated. Maximum decolourization of 98% was achieved on the third day under normal conditions. The rate of decolourization carried out at different concentrations revealed that the increase in dye effluent concentration suppresses the percentage decolourization. The optimized amounts of nutrients were found to be 0.5%, 0.1% and 0.5% of glucose, manganese sulphate and ammonium salts, respectively. The addition of inducers such as starch and lignin increased enzyme production and the rate of decolourization.

  14. Effect of CO2 enhancement on beech (Fagus sylvatica L. seedling root rot due to Phytophthora plurivora and Phytophthora cactorum

    Directory of Open Access Journals (Sweden)

    Tkaczyk Miłosz

    2014-09-01

    Full Text Available Global climate change is associated with higher concentrations of atmospheric carbon dioxide (CO2. The ongoing changes are likely to have significant, direct or indirect effects on plant diseases caused by many biotic agents such as phytopathogenic fungi. This study results showed that increased CO2 concentration did not stimulate the growth of 1-year-old beech Fagus sylvatica L seedlings but it activated pathogenic Phytophthora species (P. plurivora and P. cactorum which caused significant reduction in the total number of fine roots as well as their length and area. The results of the greenhouse experiment indicated that pathogens once introduced into soil survived in pot soil, became periodically active (in sufficient water conditions and were able to damage beech fine roots. However, the trees mortality was not observed during the first year of experiment. DNA analyses performed on soil and beech tissue proved persistence of introduced Phytophthora isolates.

  15. Monitoring of Soft Fruit Mother Plantings Aimed at Control of Phytophthora fragariae, Causal Agent of Root Rot

    OpenAIRE

    Slobodan Milenković; Dušica Sretenović

    2007-01-01

    Phytophthora fragariae was first detected in the Republic of Serbia in 2002, and it has been included in A2 quarantine list of damaging organisms since 2003. The project titled ‘Monitoring of soft fruit mother plantings aimed at the control of Phytophthora fragariae, causal agent of root rot’ was realized over 2004 – 2005 aiming at determination of population rate of the pathogen and the control of raspberry planting material. Over that period, the total 388 samples were tested. Collected sam...

  16. Monitoring of Soft Fruit Mother Plantings Aimed at Control of Phytophthora fragariae, Causal Agent of Root Rot

    OpenAIRE

    Slobodan Milenković; Dušica Sretenović

    2006-01-01

    Phytophthora fragariae was first detected in the Republic of Serbia in 2002, and it has been included in A2 quarantine list of damaging organisms since 2003. The project titled ‘Monitoring of soft fruit mother plantings aimed at the control of Phytophthora fragariae, causal agent of root rot’ was realized over 2004 – 2005 aiming at determination of population rate of the pathogen and the control of raspberry planting material. Over that period, the total 388 samples were tested. Collected sam...

  17. Microbial Properties of Composts That Suppress Damping-Off and Root Rot of Creeping Bentgrass Caused by Pythium graminicola

    OpenAIRE

    Craft, C M; Nelson, E. B.

    1996-01-01

    Composts prepared from a variety of feedstocks were tested for their ability to suppress seedling and root diseases of creeping bentgrass caused by Pythium graminicola. Among the most suppressive materials in laboratory experiments were different batches of a brewery sludge compost and a biosolids compost from Endicott, N.Y. Batches of these composts that were initially not suppressive to Pythium damping-off became more suppressive with increasing compost age. Leaf, yard waste, food, and spen...

  18. Monitoring of Soft Fruit Mother Plantings Aimed at Control of Phytophthora fragariae, Causal Agent of Root Rot

    Directory of Open Access Journals (Sweden)

    Slobodan Milenković

    2006-12-01

    Full Text Available Phytophthora fragariae was first detected in the Republic of Serbia in 2002, and it has been included in A2 quarantine list of damaging organisms since 2003. The project titled ‘Monitoring of soft fruit mother plantings aimed at the control of Phytophthora fragariae, causal agent of root rot’ was realized over 2004 – 2005 aiming at determination of population rate of the pathogen and the control of raspberry planting material. Over that period, the total 388 samples were tested. Collected samples were analyzed by PCR. The presence of Phytophthora fragariae was detected in 156 samples.

  19. Monitoring of Soft Fruit Mother Plantings Aimed at Control of Phytophthora fragariae, Causal Agent of Root Rot

    Directory of Open Access Journals (Sweden)

    Slobodan Milenković

    2006-01-01

    Full Text Available Phytophthora fragariae was first detected in the Republic of Serbia in 2002, and it has been included in A2 quarantine list of damaging organisms since 2003. The project titled ‘Monitoring of soft fruit mother plantings aimed at the control of Phytophthora fragariae, causal agent of root rot’ was realized over 2004 – 2005 aiming at determination of population rate of the pathogen and the control of raspberry planting material. Over that period, the total 388 samples were tested. Collected samples were analyzed by PCR. The presence of Phytophthora fragariae was detected in 156 samples.

  20. Alternativas de control en la pudrición radical de cebolla para el Valle de la Trinidad, Baja California Control Alternatives for Onion root rot in the Trinity Valley, Baja California

    Directory of Open Access Journals (Sweden)

    Armando Pulido-Herrera

    2012-02-01

    solarization (SPT; 6 black plastic solarization (SPN; 7 SPT + EB; 8 SPT + CR; 9 SPN + EB; 10 SPN + SO; 11 Trichodef (Trichoderma harzianum; and 12 control. In Experiment II (2008, treatments were the same except treatment 2, replaced by a protective agent (plant extracts, and in experiment III (2009 the treatments were: 1 SPT + sheep manure (EO; 2 SPN + EO; 3 SPT; 4 SPN; 5 biological control (Trichoderma spp.; and 6 chemical control (2 - (thiocyanomethylthio benzothiazole 30%. the results indicated that the clear plastic solarization treatments with or without organic amendments showed significant increases (p<0.05 from 22 to 34%yield and diameterwith respect to biological and chemical control, but the latter two treatments in the incidence and severity decreasedsignificantly (p<0.05 , so that the clearplastic solarization and biological control, are viable alternatives to control root rot in onion crops in Baja California, Mexico.

  1. Reading the “Schwarz” in the “Schwarz-Rot-Gold”: Black German Studies in the 21st Century

    OpenAIRE

    Nenno, Nancy P.

    2016-01-01

    In 2016, Black German Studies celebrates the 30th anniversary of the publication of Farbe bekennen: Afrodeutsche Frauen auf den Spuren ihrer Geschichte. The result of the encounter of Black German women in Berlin with Afro-Caribbean American activist-poet Audre Lorde in the mid-1980s, this text testifies to the power of transnational collaboration in the assertion of Black agency, as well as to the influence of American feminist and civil rights discourses in the West German context. The trut...

  2. Tomato susceptibility to Fusarium crown and root rot: effect of grafting combination and proteomic analysis of tolerance expression in the rootstock.

    Science.gov (United States)

    Vitale, Alessandro; Rocco, Mariapina; Arena, Simona; Giuffrida, Francesco; Cassaniti, Carla; Scaloni, Andrea; Lomaglio, Tonia; Guarnaccia, Vladimiro; Polizzi, Giancarlo; Marra, Mauro; Leonardi, Cherubino

    2014-10-01

    Grafting can enhance the tolerance of vegetable crops to soilborne diseases. The aim of this study was to investigate whether different tomato scion-rootstock combinations may affect the plant susceptibility to Fusarium oxysporum f. sp. radicis-lycopersici (FORL), the causal agent of crown and root rot. A proteomic approach was used to investigate whenever the protein repertoire of the rootstock can be modified by FORL infection, in relation to cultivar susceptibility/tolerance to the disease. To this purpose, plants of tomato hybrids with different vigor, "Costoluto Genovese" (less vigorous) and "Kadima" (more vigorous), were grafted onto "Cuore di Bue" and "Natalia" hybrids, sensitive and tolerant versus FORL infections, respectively. Disease symptoms, plant biomasses, and protein expression patterns were evaluated 45 days after FORL inoculation. The extent of vascular discoloration caused by FORL in tomato plants grafted on "Natalia" rootstock (0.12-0.37 cm) was significantly lower than that of plants grafted on sensitive "Cuore di Bue" (1.75-6.50 cm). FORL symptoms significantly differed between "Costoluto Genovese" and "Kadima" scions only when grafted on sensitive rootstock. Shoot FW of non-inoculated "Kadima"/"Cuore di Bue" combination was 35% lower than "Kadima"/"Natalia", whereas no difference was manifested in inoculated plants. Shoot FW of inoculated "Costoluto Genovese"/"Cuore di Bue" combination was decreased of 39%, whereas that of "Costoluto Genovese"/"Natalia" of 11%, compared to control plants. Proteomic results showed a higher representation of proteins associated with pathogen infection in the tolerant rootstock, compared to the sensitive one, meaning a direct involvement of plant defence mechanisms in the tomato response to the pathogen challenge. PMID:25173633

  3. In vitro selection of an effective fungicide against Armillaria mellea and control of white root rot of grapevine in the field.

    Science.gov (United States)

    Aguín, Olga; Mansilla, J Pedro; Sainz, María J

    2006-03-01

    Armillaria mellea (Vahl ex Fr) Kummer is an aggressive pathogen which causes white root rot in a wide range of hosts. Most chemicals tested so far against Armillaria, both in vitro and in the field, have not been effective in reducing fungal growth and/or preventing plant decline and mortality. In the present work the effects of four DMI (sterol demethylation inhibitor) fungicides, cyproconazole, hexaconazole, propiconazole and tetraconazole, and another six downwardly mobile systemic chemicals, azoxystrobin, cubiet (copper bis(ethoxy-dihydroxy-diethylamino)sulfate), fosetyl-Al, potassium phosphite, sodium tetrathiocarbonate (STTC) and 2-(thiocyanomethylthio)benzothiazole (TCMTB), on the mycelial growth of A. mellea were compared and evaluated; the product yielding the best results in in vitro experiments was selected to determine its efficacy in preventing decline and mortality of grapevines in the field. Best results on in vitro fungal growth reduction were obtained with the four azoles tested, in particular with cyproconazole and hexaconazole, achieving 67-72% mycelial growth inhibition at the lowest dose. Results obtained in the field showed that a dose of 50 mg AI litre(-1) of cyproconazole once or twice a year was efficient in controlling the disease even in vines seriously affected by the pathogen. However, further research is required to study minimum effective doses, residual effects and the convenience of the application of annual dressings in damaged vineyards, so as to gradually reduce the pathogen inoculum potential in soil and control the disease while reducing chemical residues in the plant and preventing development of fungal resistance. PMID:16475239

  4. Identification of Biocontrol Bacteria against Soybean Root Rot with Biolog Automatic Microbiology Analysis System%拮抗大豆根腐病细菌的Biolog鉴定

    Institute of Scientific and Technical Information of China (English)

    许艳丽; 刘海龙; 李春杰; 潘凤娟; 李淑娴; 刘新晶

    2012-01-01

    In order to identify the systematic position of taxonomy of two biocontrol bacteria against soybean root rot. Traditional morphological identification and BIOLOG automatic microbiology analysis system were used to identify strain B021a and B04b. The results showed that similarity value of strain B021a with Vibrio tubiashii was 0. 634, possibility to 86% and genetic distance to 4.00,and similarity value of strain B04b with Pasteurella trehalosi was 0. 610,probability to 75% and genetic distance to 2. 77. Strain B021a was identified as Vibrio tubiashii and strain B04b as Pasteurella trehalosi by colony morphological propertie and BIOLOC analysis system.%为明确2株生防细菌的分类地位,采用传统形态学方法结合Biolog微生物自动分析系统,鉴定了大豆根腐病的2株生防细菌.结果表明,菌株B021a与塔式弧菌相似度值为0.634,可能性是86%,遗传距离为4.00.菌株B04b与海藻巴斯德菌相似度值为0.610,可能性是75%,遗传距离为2.77.综合形态学和Biolog鉴定结果,认为菌株B021a是塔式弧菌,菌株B04b是海藻巴斯德菌.

  5. 文山三七根腐病病原真菌的鉴定与药剂防治%Identification of Root Rot Pathogen of Panax notoginseng from Wenshan

    Institute of Scientific and Technical Information of China (English)

    汪静; 梁宗锁; 康冰; 罗美佳

    2015-01-01

    从云南文山三七药材基地感染根腐病的三七组织获得分离物,并对其进行培养和纯化,并运用科赫法则(Koch,s Postulate)进行病原菌回接感染,得3株致病明显的菌株,后对此菌株进行生物学和18S-rDNA全序列分析鉴定及室内药效防治.结果表明,此3株菌分别是尖孢镰刀菌(Fusarium oxysporum),茄病镰刀菌(Fusarium solani)和链格孢菌(Alternaria alternata).甲基硫菌灵、根康、多菌灵对茄孢镰孢菌、尖镰孢菌的抑菌效果最好,腐霉利、甲基硫菌灵对链格孢菌的抑菌效果最好.该研究可为尖孢镰刀菌、茄病镰刀菌和链格孢菌引起的三七根腐病的防治提供参考.%To isolate and identify root rot pathogens of Panax notoginseng to lay the foundation for the prevention of the root rot disease.P.notoginseng root rot tissues and soils around roots were colleted in Wenshan,Yunnan.Microorganisms were examined based on Koch 's Postulate and 18S-rDNA sequence analysis.The results showed that in vitro pathogenecity tests demonstrated that Fusarium oxysporum,Fusarium solani and Alternaria alternate could result in the disease at different levels.The results of the PDA plate bacteriostatic experiment indoor showed that thiophanate-methyl,Genkang,and carbendazim had the best control effects on F.oxysporum,F.solani.While thiophanate-methyl,procymidone had the best control effect on A.alternate.F.oxysporum,F.solani and A.alternate were considered as three of the most important fungi causing P.notoginseng root-rot diseases.

  6. Efficacy of wild plant in combination with microbial antagonists for the control of root rot fungi on mungbean and cowpea

    International Nuclear Information System (INIS)

    Present work was carried out to investigate the efficacy of Aerva javanica in combination with different microbial antagonists namely Rhizobium meliloti, Pseudomonas aeruginosa, Trichoderma harzianum and Aspergillus niger. Soil amended with A. javanica stem, leaves, flower powder at the rate1% w/w and seeds of cowpea (Vigna unguiculata L.) and mungbean (Vigna radiata L.) were coated with microbial antagonists for the control of root infecting fungi like Macrophomina phaseolina (Tassi) Goid, Fusarium spp. and Rhizoctonia solani Kiihn. Infection of M. phaseolina and R. solani were completely suppressed when seeds were coated with P. aeruginosa, T. harzianum, A. niger, R. meliloti and A. javanica leaves powder mixed in soil at the rate 1% w/w. All antagonists showed reduction in combination with A. javanica leaves powder at the rate1% but T. harzianum and P. aeruginosa in combination with A. javanica leaves showed promising results in complete reduction of R. solani and M. phaseolina on both crops. All growth parameters were maximum when soil was amended with A. javanica leaves powder at the rate 1% w/w and seeds were coated with T. harzianum and P. aeruginosa. (author)

  7. Control of Black Rot Disease in Tomato Fruits by Using Formulated Ginger Essential oil Treated by Gamma Radiation

    International Nuclear Information System (INIS)

    Ginger essential oil (Zingiber officinale) treated by gamma radiation at dose of 10 kGy was selected as an active ingredient for formulation of the biocide. Liquid formulations (emulsifiable concentrates) were prepared using different emulsifiers (Emulgator B.L.M. and tween 80 or tween 20) and additive oil (soybean oil). Physicochemical properties of the formulated oil (spontaneous emulsification, emulsion stability; cold stability and heat stability, viscosity, surface tension and ph) were measured. The formulated oil was tested in vivo to investigate its efficiency for controlling the growth of Alternaria alternata inoculated into tomato fruits. The results indicated that soaking inoculated tomato fruits in the formulated oil (ginger essential oil + soybean oil + emulgator B.L.M. + tween 80) treatment at concentration of 300 ppm for a period of 12 minute was the most effective for controlling the growth of the tested fungus. In addition, the formulated oil had efficiency for controlling the rot development on tomato fruits when applied as therapeutic and protective agents

  8. Chemigation for Control of Black Shank-Root-knot Complex and Weeds in Tobacco

    OpenAIRE

    Johnson, A. W.; Csinos, A.S.; Golden, A. M.; Glaze, N. C.

    1992-01-01

    Tank mixes of a fungicide (metalaxyl) and a nematicide (fenamiphos) with herbicides (isopropalin or pendimethalin) and an insecticide (chlorpyrifos) were applied by soil incorporation or irrigation to control the black shank-root knot complex and weeds on four tobacco cultivars. The disease complex was more severe on cultivars McNair 944, NC-2326, and K-326 than on Speight G-70. The disease complex was reduced (P ≤ 0.05) on all cultivars with the pesticide combinations containing metalaxyl + ...

  9. 甘肃高寒阴湿区豌豆根腐镰刀菌种群及致病性研究%Fusarium Population and Pathogenicity of Pea Root Rot in the Cold and Humid Regions of Gansu Province

    Institute of Scientific and Technical Information of China (English)

    刘小娟; 侯思雯; 杨晓明; 李敏权

    2012-01-01

    甘肃省高寒阴湿区豌豆镰刀菌根腐病的病原有5种,即茄病镰刀菌[ Fusarium solani ( Mart.) Sacc]、茄病镰刀菌蓝色变种(Fusarium solani var.coeruleum)、半裸镰刀菌(Fusarium semitectum)、单隔镰刀菌(Fusarium dimerum)、拟丝孢镰刀菌(Fusarium trichothecioides).茄病镰刀菌致病性最强,拟丝孢镰刀菌和茄病镰刀菌蓝色变种次之,半裸镰刀菌和单隔镰刀菌的致病性较弱.其中半裸镰刀菌、单隔镰刀菌、拟丝孢镰刀菌是中国豌豆病原菌上的新纪录.%The pathogen of pea Fusarium root rot in the cold and humid regions of Gansu were Fusarium solani (Mart. ) Sacc., Fusarium solani var. Coeruleum,, Fusarium semitectum ? Fusarium dimerum and Fusarium trichothe-cioides. The most pathogeniciry pathogen was F. Solani, while F. Trichothecioides, and F. Solani var. Coeruleum were the second;however F. Semitectum and F. Dimerum were the least pathogenicity pathogens. F. semitectumNF. Dime-rum ^F. Trichothecioides were new recorded on pea Fusarium root rot in China.

  10. 北疆地区打瓜镰刀菌根腐病药剂防治研究%Study on Fungicides for Controlling Root Rot of Seed Watermelon in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    朱亚峰; 李平; 金玉华; 张莉

    2013-01-01

    [Objective] Root rot of seed watermelon (Fusarium solani) is a major disease to seed watermelon in Xinjiang,the control efficacy of six fungicides to root rot was studied.The objective was to make some contributions to the control of the disease.[Method] The control efficacy of six bactericides to root rot of seed watermelon with experiments of indoor toxicity trials,potted trials and field plot trials were compared.[Result] Indoor toxicity trials shows that ethylicin is the most effective fungicide against the pathogen with EC50 of 31 mg/L,then it is followed by carbendazim,hymexazol,difenoconazole-thiram,bacillus subtilis,trichloroisocyanuric acid.Potted trials show that the control efficacy of irrigating roots is better than seed dressing.The control effects of carbendazim is the highest,the average control efficacy reached to 83.0%,followed by hymexazol and difenoconazole-thiram,with the average control efficacy of 64.4% and 60.2%.Field plot trials show that the control effects of difenoconazole-thiram is the highest,which the average control efficacy reached to 46.6%,followed by carbendazim and hymexazol,with the average control efficacy of 45.3% and 45.1%.[Conclusion] Difenoconazole-thiram,carbendazim and hymexazol have better control effect against root rot of seed watermelon%[目的]打瓜根腐病是北疆地区打瓜上的重要病害,明确几种杀菌剂对打瓜根腐病的防治效果,为打瓜根腐病的有效防治奠定基础.[方法]采用室内毒力测定、盆栽药效试验和小区药效试验,比较6种杀菌剂对打瓜根腐病的防治差异.[结果]室内毒力测定表明:乙蒜素对菌丝生长抑制效果最好,EC50值为31 mg、L,其他依次为多菌灵、恶霉灵、苯甲·福美双、枯草芽孢杆菌、三氯异氰尿酸.盆栽试验表明:药剂灌根的防治效果比药剂拌种好,其中多菌灵灌根防治效果最好,防治效果为83.0%,其次是恶霉灵和苯甲·福美双,防治效果分别为64.4

  11. Effect of BRF-1 and BRF-2 on Root Rot and Seed Yield in Soybean%生防菌BRF-1和BRF-2对大豆根腐病和产量的影响

    Institute of Scientific and Technical Information of China (English)

    周克琴; 韩秉进; 张秋英; 刘文志; 宫学凯; 李艳华; 孟英; 王光华

    2012-01-01

    BRF-1 (Paenibacillus Polymyxa) and BRF-2 {Bacillus subtilis) are gram-positive bacteria obtained from soybean root rhizosphere. Dual-culture tests showed they had strong antagonism to many fungal pathogens,while they inhibited the development of plant diseases in vitro experiment. In 2010,a field trial with BRF-1 and BRF-2 was carried out in northern region of Heilongjiang Province to investigate their field performance in reducing disease incidence of soybean. Both BRF-1 and BRF-2 inhibited soybean root rot with a reduction in disease severity index by 44.4% and 8. 8% ,respectively. BRF-1 was a potential plant growth promoting bacteria in controlling soybean root rot,which increased above-ground dry matter and root dry matter accumulation at flowering and initial seed-filling stages,and thus enhanced seed yield by 5.9%.%BRF-1和BRF-2是中国科学院东北地理与农业生态农田分子生态学科组从大豆根际土壤筛选得到的2株革兰氏阳性生防细菌,为了检测它们对田间大豆根腐病的防治效果,2010年在沈阳军区龙镇农副业基地对BRF-1和BRF-2进行田间试验.结果表明:2株生防细菌均有效地抑制了大豆根腐病的发生,发病程度分别降低44.4%和8.8%,BRF-1菌株效果较好,在降低大豆根腐病病情指数的同时,能增加大豆植株花期、始粒期地上部和地下部干物重,提高大豆产量5.9%,是一株很有潜力的生防菌.

  12. Screening,Identification and Biocontrol Potential of Antagonistic Fungi Against Strawberry Root Rot and Plant Growth Promotion%草莓根腐病拮抗真菌筛选鉴定及其防病促生作用

    Institute of Scientific and Technical Information of China (English)

    申光辉; 薛泉宏; 张晶; 段佳丽; 王东胜; 杨兴华

    2012-01-01

    fungi based on root-zone microflora differentiae between healthy and root rot diseased strawberry plants. [Method] The isolated antagonistic fungi were identified according to colony and morphological characteristics observed by scanning electron microscope (SEM) and rDNA-ITS sequences analysis. Mycelium growth rate method and slide dual culture method were used to investigate antagonistic activity of cell-free culture filtrate and the antagonistic effect of antagonistic fungi against soil-borne pathogens, respectively. The seed germination promotion activity of culture filtrate was measured by Petri dish assays: A pot experiment was conducted to evaluate the control efficiency of antagonistic fungi against strawberry root rot caused by Cylindrocarpon macrodidyma CF9 and plant growth promotion effect. Colonization capacity and microbial flora were also determined by dilution plate count method. [Result] Strain HF3 and strain HF7 were identified as Penicillium griseofulvum and Aspergillus terreus, respectively. The cell-free culture filtrate both of two strains exhibited strong antagonistic effect on mycelium growth of test pathogens. The mycelium inhibitory rate of strain HF3 culture filtrate on Rhizoctonia solani and Verticillium dahliae were 100.0% after 96 h. It was also observed that HF3 broke the hyphae of C. macrodidyma CF9, such as contorting, slimmer, bulging, dissolved, protoplasm condense. It was observed that 103 and 104 diluted-fold filtrate of two strains enhanced the melon seed germination and growth, 104 diluted-fold filtrate of HF7 promoted seed germination, plumule and radicle growth of watermelon. In a pot experiment, the control efficiency against root rot of strawberry of HF3 and HF7 were 53.0% and 46.9%, respectively. Moreover, two antagonistic strains exhibited strawberry plant growth promotion as well as fruit yield enhancement. HF3 and HF7 efficiently colonized strawberry root with rhizoplane densities 2.23×105, 1.02×l05 CFU·g-1 dry soil

  13. Effect of Black Polyethylene Mulch and Calcium Nitrate Application on Growth, Yield, and Blossom-End Rot of Watermelon, cv. Charleston Gray

    OpenAIRE

    H. Lessani; M. Babalar; Hosseinzadeh, S.; A. Kashi

    2004-01-01

    Watermelon (Citrullus Lanatus) cv. Charleston Gray is one of the most important cultivars grown in Iran. It has some good quantitative and qualitative characteristics but unfortunately is sensitive to Blossom End rot. To solve this problem, this experiment was conducted in a factorial manner in randomized complete block design with four replications in Research Station and Laboratories of Department of Horticulture, College of Agriculture, the University of Tehran, during 1997 & 1998. In ...

  14. Screening of Rhizobacteria for Their Plant Growth Promotion Ability and Antagonism Against Damping off and Root Rot Diseases of Broad Bean (Vicia faba L.)

    OpenAIRE

    S Indira Devi; Talukdar, N. C.; K. Chandradev Sharma; Jeyaram, K.; Rohinikumar, M.

    2011-01-01

    Development of microbial inoculants from rhizobacterial isolates with potential for plant growth promotion and root disease suppression require rigorous screening. Fifty-four (54) fluorescent pseudomonads, out of a large collection of rhizobacteria from broad bean fields of 20 different locations within Imphal valley of Manipur, were initially screened for antifungal activity against Macrophomina phaseolina and Rhizoctonia solani, of diseased roots of broad bean and also three other reference...

  15. Fungi Diversity of Rhizosphere Soil with Loquat Root Rot Disease in Yunnan Province%云南蒙自枇杷根腐病植株根际土壤真菌多样性研究

    Institute of Scientific and Technical Information of China (English)

    杨若鹏; 郑肖兰; 田学军; 李建平; 鲁海菊

    2012-01-01

    摘要摸清蒙自枇杷根腐病病株根际土壤真菌区系分布.为有效可持续防控枇杷根腐病提供理论依据。采用五点取样法采集土壤样品,稀释平板法在PDA培养基上分离纯化,获得114株枇杷根腐病病株根际土壤真菌,经显微镜形态鉴定。109株真菌鉴定为以下24种: A bs idia corymbifera, A bsidia cylindrospora, A bsidia spinosa,Acremonium cerealis, Acremonium murorum, Aspergillus niger, Cladosporium cladosporioides, Colletotrichum dematium, Fusarium flocciferum, Mucor circineUoides f. janssenii, Mucor circinelloides f. wsitanicus, PeniciUium atrovenetum, Penicillium canescens, PeniciUium chrysogenum, Penicillium corylophilum, Penicillium daleae, Penicillium digitatum, Penicillium nigricans, Penicillium oxalicum, Penicillium saceulum, Penicillium variabile,Pythium intermedium, Trichoderma strigosum, Verticillium fungicola,分属于11个属.其中青霉属(Penicillium)是优势属,另外5株真菌属于担子菌。%To establish the species and distribution of fungi of Loquat rhizosphere soil which had rot root disease at Mengzi in Yunnan Province and to provide theoretical basis for efficient control to disease of the root rot; Soil specimen were collected with the 5-point method. The fungi strains were isolated by the plate of gradient dilution with PDA medium. The strains were identified by morphology with microscope. The strains respectively belong to A bsidia corymbifera, A bsidia cylindrospora, A bsidia spinosa, A cremonium cerealis, Acremonium murorum, Aspergillus niger, Cladosporium cladosporioides, Colletotrichum dematium, Fusarium flocciferum, Mucor circinelloides f. janssenii, Mucor circineUoides f. wsitanicus, Penicillium atrovenetum, Penicillium canescens, Penicillium chrysogenum, Penicillium corylophilum, PeniciUium daleae, Penicillium digitatum, Penicillium nigricans, PeniciUium oxalicum, Penicillium saceulum, PeniciUium variabile, Pythium intermedium, Trichoderma strigosum

  16. Epidemiologia comparativa da podridão negra e da alternariose do repolho no Agreste de Pernambuco Comparative epidemiology of black rot and Alternaria black spot of cabbage in the Agreste of Pernambuco

    Directory of Open Access Journals (Sweden)

    SIMONE S. AZEVÊDO

    2002-02-01

    Full Text Available A podridão negra causada por Xanthomonas campestris pv. campestris, e a alternariose causada por Alternaria brassicicola constituem importantes doenças do repolho no estado de Pernambuco. Em virtude do desconhecimento sobre a epidemiologia dessas doenças a nível regional, foi efetuada a análise comparativa das epidemias com ênfase nos aspectos temporais e espaciais, em 1997 e 1998, cada ano em uma área de plantio diferente, localizadas no município de Camocim de São Félix, Agreste de Pernambuco. Em cada área, a intervalos semanais, foram avaliadas 1.920 plantas quanto à incidência e severidade das duas doenças, bem como efetuado o mapeamento espacial de plantas assintomáticas e sintomáticas. Os valores iniciais (y o e máximos (y max de incidência e severidade, as taxas estimadas de progresso da doença (k e as áreas abaixo das curvas de progresso das doenças (AACPD, apresentaram pequena variação entre as doenças, sendo as diferenças mais evidentes entre os anos de plantio. As maiores intensidades das doenças foram observadas em 1998, uma vez que próximo à área de plantio havia grande quantidade de plantas e restos culturais infetados, o que não ocorreu em 1997. Pelas análises de "ordinary runs", ajuste à distribuição beta-binomial e autocorrelação espacial, na maioria das situações, foi constatado um arranjo aleatório de plantas doentes nas avaliações iniciais, evoluindo posteriormente para um arranjo agregado, indicando que as doenças podem ter sido originadas de aloinfecções pela chegada de inóculo externo, seguidas de autoinfecções decorrentes da disseminação planta-a-planta.The black rot caused by Xanthomonas campestris pv. campestris and Alternaria black spot caused by Alternaria brassicicola are significant cabbage diseases in the State of Pernambuco, Brazil. A lack of knowledge on the epidemiology of these diseases at a regional level motivated a comparative analysis of the epidemics in

  17. Inoculation of root microorganisms for sustainable wheat-rice and wheat-black gram rotations in India

    OpenAIRE

    Mäder, Paul; Kaiser, Franziska; Adholeya, Alok; Singh, Reena; Uppal, Harminder S.; Sharma, Anil K.; Srivastava, Rashmi; Sahai, Vikram; Aragno, Michel; Wiemken, Andres; Johri, Bhavdish N.; Fried, Padrout M.

    2011-01-01

    The scarcity of non-renewable resources such as soils and fertilizers and the consequences of climate change can dramatically influence the food security of future generations. Mutualistic root microorganisms such as plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) can improve plant fitness. We tested the growth response of wheat (Triticum aestivum [L.]), rice (Oriza sativa [L.]) and black gram (Vigna mungo [L.], Hepper) to an inoculation of AMF and PGPR alon...

  18. Screening of Rhizobacteria for Their Plant Growth Promotion Ability and Antagonism Against Damping off and Root Rot Diseases of Broad Bean (Vicia faba L.).

    Science.gov (United States)

    Indira Devi, S; Talukdar, N C; Chandradev Sharma, K; Jeyaram, K; Rohinikumar, M

    2011-01-01

    Development of microbial inoculants from rhizobacterial isolates with potential for plant growth promotion and root disease suppression require rigorous screening. Fifty-four (54) fluorescent pseudomonads, out of a large collection of rhizobacteria from broad bean fields of 20 different locations within Imphal valley of Manipur, were initially screened for antifungal activity against Macrophomina phaseolina and Rhizoctonia solani, of diseased roots of broad bean and also three other reference fungal pathogens of plant roots. Fifteen fluorescent pseudomonas isolates produced inhibition zone (8-29 mm) of the fungal growth in dual plate assay and IAA like substances (24.1-66.7 μg/ml) and soluble P (12.7-56.80 μg/ml) in broth culture. Among the isolates, RFP 36 caused a marked increase in seed germination, seedling biomass and control of the root borne pathogens of broad bean. PCR-RAPD analysis of these isolates along with five MTCC reference fluorescent pseudomonas strains indicated that the RFP-36 belonged to a distinct cluster and the PCR of its genomic DNA with antibiotic specific primers Phenazine-1-carboxylic acid and 2, 4-diacetyl phloroglucinol suggested possible occurrence of gene for the potent antibiotics. Overall, the result of the study indicated the potential of the isolate RFP 36 as a microbial inoculant with multiple functions for broad bean. PMID:22282623

  19. Incorporation of disease resistance from Lycopersicon peruvianum L. to cultivated tomatoes, 1: Breeding of new varieties ''Ryugyoku'' etc., having resistance to Fusarium root rot and tobacco mosaic virus inherited from L. peruvianum

    International Nuclear Information System (INIS)

    Fusarium crown and root rot (FCR) resistance and Tobacco Mosaic Virus (TMV) resistance (Tm-2) of a wild tomato (Lycopersicon peruvianum) were incorporated into cultivated tomatoes (L. esculentum). With this material, F1 hybrid varieties 'Kagyoku, Ryugyoku' and their parental lines 'Tomato parental lines No. 4, -No. 5' were developed. In addition, 'Kagyoku, Ryugyoku' possess Fusarium wild (J1), Nematode (Meloidogyne incognita) and TMV (Tm-2a) resistance introduced from the other varieties. Among the resistances introduced from L. peruvianum, TMV resistance is simply inherited and stable enough. FCR resistance is basically monogenic, but the strong influence of the genetic background hinders the development of FCR resistant varieties with high quality and yield. Whereas 'Ryugyoku' which is highly resistant to FCR has less attractive fruit characters, 'Kagyoku' yields fruits of high quality with a comparatively low FCR resistance. In this report, the breeding process from interspecific hybridization to the development of F1 varieties and the methods of selection applied were described. Also the difficulties which arose in the process of incorporation of the resistance from the wild species were discussed

  20. Levantamento da intensidade da alternariose e da podridão negra em cultivos orgânicos de brássicas em Pernambuco e Santa Catarina Survey of the intensity of Alternaria black spot and black rot on brassica species under organic farming systems in Pernambuco and Santa Catarina states, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz A M Peruch

    2006-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a intensidade da alternariose, causada por Alternaria brassicicola e/ou Alternaria brassicae, e da podridão negra, causada por Xanthomonas campestris pv. campestris, em cultivos orgânicos de brássicas em Pernambuco e Santa Catarina. Os levantamentos foram realizados no período de novembro de 2001 a fevereiro de 2002, num total de 103 cultivos orgânicos de várias espécies de brássicas. Foram registradas elevadas prevalências das doenças nos estados, com exceção em couve-chinesa em Santa Catarina. A prevalência da alternariose foi 100% nos cultivos de brócolis em Pernambuco, bem como em couve-flor nos dois estados, enquanto a podridão negra atingiu esse nível nos cultivos de brócolis e couve-flor em Santa Catarina. Na média das diferentes espécies de brássicas, as doenças foram mais prevalentes em Pernambuco que Santa Catarina. Entretanto, as médias de severidade de cada doença no conjunto das brássicas não foram diferentes entre os estados, embora as condições climáticas tenham sido nitidamente distintas. A severidade da alternariose variou entre as espécies de brássicas somente em Pernambuco, com a menor severidade registrada em couve-manteiga. Em relação à podridão negra, apenas em Santa Catarina houve diferença na severidade entre as brássicas, sendo registrados os menores níveis em couve-chinesa. Não foram constatadas correlações significativas entre os níveis de severidade da alternariose e da podridão negra, bem como da severidade destas com o número total de plantas e a idade das plantas nos cultivos.The objective of this research was to evaluate the intensity of Alternaria black spot, caused by Alternaria brassicicola and/or Alternaria brassicae, and black rot, caused by Xanthomonas campestris pv. campestris in organic cultivation of brassicas in Pernambuco and Santa Catarina. The survey was carried aut from November 2001 to February 2002, in 103 fields under

  1. Effects of cell suspension and cell·free culture filtrate of Pseudomonas aeruginosa in the control of root rot-root kont disease complex of tomato (Lycopersicon esculentum Mill.

    Directory of Open Access Journals (Sweden)

    I. A. Siddiqui

    2013-12-01

    Full Text Available The plant growth-promoting rhizobacterium Pseudomonas aeruginosa strain IE-6 was tested for antagonistic activity towards Meloidogyne javanica, the root-knot nematode and soilbome root-infecting fungi viz., Macrophomina phaseolina, Fusarium solani and Rhizoctonia solani under laboratory and greenhouse conditions. Cell-free culture filtrate of the bacterium caused significant reduction in egg hatching of M.javanica and inhibited radial growth of fungi in vitro. Cell-free culture filtrate also caused lyses in mycelium of F.solani. Under greenhouse conditions, soil drenches with the aqueous cell suspension or cell-free culture resulted in a considerable reduction in nematode population densities in soil and subsequent root-knot development due to M.javanica. In addition to nematode control, rhizobacterium application also inhibited root-infection caused by soilborne root~infecting fungi with significant enhancement of growth of tomato seedlings.

  2. Root distribution pattern of bush - black pepper (Piper nigrum L.) employing radiotracer technique

    International Nuclear Information System (INIS)

    Root distribution pattern of four-year-old field planted bush pepper (Piper nigrum L.) was studied at Peruvannamuzhi farm of Indian Institute of Spices Research by radiotracer technique. The root zone, up to 30 cm radius and 40 cm depth was round to be the active root zone of bush pepper variety Karimunda grown in the field. (author)

  3. Integrated Management of Damping-off, Root and/or Stem Rot Diseases of Chickpea and Efficacy of the Suggested Formula

    OpenAIRE

    Montaser Fawzy ABDEL-MONAIM

    2011-01-01

    Eleven fungal isolates were isolated from naturally infected chickpea roots collected from different locations in New Valley Governorate (Egypt). The isolated fungi were purified and identified as Rhizoctonia solani (5 isolates), Fusarium solani (4 isolates) and Sclerotinia sclerotiorum (2 isolates). The isolated fungi proved their pathogenicity on cv. �Giza 3�. Response of chickpea cvs. �Giza 1�, �Giza 2�, �Giza 3�, �Giza 4�, �Giza 88�, �Giza 195�, �Giza 531� to infection by the tested fungi...

  4. Propagation of Black Plum (Vitex donania Sweet Using Stem and Root Cuttings in the Ecological Conditions of South-Benin

    Directory of Open Access Journals (Sweden)

    Sanoussi, A.

    2012-01-01

    Full Text Available The black plum is a multi-purpose tree well known to the rural and urban populations of tropical Africa. Its uses are well documented, but its regeneration possibilities have not yet been studied, despite the importance of this species. The objective of this study is to ensure that this tree can be propagated from other organs instead of seeds. In order to achieve this, a trial propagation, using stem and root cuttings, was conducted on two types of substrate: topsoil at the planting site (sand mixed with poultry manure and soil taken from undergrowth at the forest research station in Pobe, which focuses on the oil palm tree. The trial was based on a randomised complete block, two factors and four treatments. The results show that it is possible to propagate black plum trees from stem cuttings (46.62% of developed cuttings but especially from root cuttings (96.25% of developed cuttings. The compared treatments significantly influenced the recovery rate of the cuttings. The first leaf produced by the stem cuttings is multi-lobed (3-5 lobes, while that produced by root cuttings is generally single-lobed. One year after transplanting, the substrate (2/3 sand and 1/3 chicken manure in volume produced the best plant growth from cuttings.

  5. 薰衣草精油对樱桃番茄采后黑斑病的抑制活性%Control of black rot disease in postharvest cherry tomato with lavender oil

    Institute of Scientific and Technical Information of China (English)

    任雪艳; 梁卓; 王慧敏; 闫帆; 魏玉荣; 孔庆军

    2014-01-01

    This experiment was conducted to study the inhibitory effect and action mode of lavender oil against black rot in postharvest cherry tomato caused by Alternaria alternata by means of fumigation and direct contact. Lavender oil fumi-gation with the dosage of 5 μl per petri dish or direct contact at 400 μl/L could inhibit the growth of A. alternata complete-ly. The incidences of black rot were reduced by 54% and 60% in post harvest cherry tomatoes fumigated with 100 μl/L lavender oil and directly contacted with 500 μl/L lavender oil respectively. An inhibitory effect of short-time lavender oil treatment was shown on A. alternata while a lethal effect of long-time lavender oil treatment was exhibited.%为薰衣草精油用于防治樱桃番茄采后黑斑病提供依据,研究了薰衣草精油熏蒸和直接接触对病原真菌链格孢( Alternaria alternata)的抑制活性及作用方式。结果表明,在培养基培养试验中,每皿5μl的薰衣草精油熏蒸即可完全抑制病原菌的生长;当400μl/L薰衣草精油直接接触链格孢病原菌时,可完全抑制病原菌的生长。在薰衣草精油对樱桃番茄果实采后黑斑病抑制效果试验中发现,100μl/L精油熏蒸处理果实时,处理组果实发病率比对照组降低54%,用500μl/L精油直接处理果实时,处理组果实发病率则比对照组降低60%。在薰衣草精油对病原真菌链格孢作用方式试验中,薰衣草精油作用时间短时,对链格孢病原菌生长有抑制作用,薰衣草精油作用时间长时(5 d和7 d)对链格孢病原菌有致死效应。

  6. Occurrence and impact of the root-rot biocontrol agent Phlebiopsis gigantea on soil fungal communities in Picea abies forests of northern Europe.

    Science.gov (United States)

    Menkis, Audrius; Burokienė, Daiva; Gaitnieks, Talis; Uotila, Antti; Johannesson, Hanna; Rosling, Anna; Finlay, Roger D; Stenlid, Jan; Vasaitis, Rimvydas

    2012-08-01

    The aim of this study was to assess belowground occurrence, persistence and possible impact of the biocontrol agent Phlebiopsis gigantea (Fr.) Jülich on soil fungi. Sampling of soil and roots of Picea abies (L.) H. Karst. was carried out at 12 P. gigantea-treated and five nontreated control sites representing 1- to 60-month-old clear-cuts and thinned forest sites in Finland and Latvia. The 454-sequencing of ITS rRNA from fine roots, humus and mineral soil resulted in 8626 high-quality fungal sequences. Phlebiopsis gigantea represented 1.3% of all fungal sequences and was found in 14 treated and nontreated sites and in all three substrates. In different substrates, the relative abundance of P. gigantea at stump treatment sites either did not differ significantly or was significantly lower than in nontreated controls. No significant correlation was found between the time elapsed since the tree harvesting and/or application of the biocontrol and abundance of P. gigantea in different substrates. In conclusion, the results demonstrate that P. gigantea occasionally occurs belowground in forest ecosystems but that stump treatment with the biocontrol agent has little or no impact on occurrence and persistence of P. gigantea belowground, and consequently no significant impact on soil fungi. PMID:22443512

  7. INFLUÊNCIA DO PREPARO DE SOLO E DA ROTAÇÃO DE CULTURAS NA SEVERIDADE DE PODRIDÕES RADICULARES NO FEIJOEIRO COMUM EFFECTS OF SOIL TILLAGE SYSTEM AND CROP ROTATION ON DRY BEAN ROOT ROT SEVERITY

    Directory of Open Access Journals (Sweden)

    Pedro Marques da Silveira

    2007-09-01

    Full Text Available

    As podridões radiculares do feijoeiro são causadas pelos fungos Rhizoctonia solani Kühn e Fusarium solani f. sp. phaseoli Snyd. & Hans. Neste trabalho testou-se a combinação dos fatores preparo de solo e rotação de culturas, além de se avaliarem seus efeitos sobre as podridões radiculares do feijoeiro. Os tipos de preparo de solo consistiram em: arado+grade (P1, arado (P2, grade (P3 e plantio direto (P4. As rotações de culturas foram: arroz-feijão (R1, milho-feijão (R2, arroz/calopogônio (Calopogonium muconoides-feijão (R3 e milho-feijão-milho-feijão-arroz-feijão (R4. A severidade de F. solani f. sp. phaseoli, avaliada aos 25 dias após o plantio, apresentou interação significativa, sendo a maior severidade encontrada na combinação da rotação R3 com o preparo de solo P1, e a menor severidade, na combinação da rotação R2 com o preparo de solo P3. Diferenças estatísticas ocorreram na severidade da doença provocada por R. solani. O preparo de solo P3 apresentou maior severidade que P4, e, entre as rotações, R3 apresentou a maior severidade da doença.

    PALAVRAS-CHAVE: Rhizoctonia solani; Fusarium solani f. sp. phaseoli; práticas culturais; fungos.

    Dry bean root rot is caused by the fungi Rhizoctonia solani Kühn and Fusarium solani f. sp. phaseoli Snyd. & Hans.The effects of the interaction between soil tillage systems andcrop rotation on the severity of root rot was tested. The soiltillage systems consisted of plough+harrow (P1, plough (P2,harrow (P3 and no tillage (P4 and the crop rotation treatmentswere rice-bean (R1, corn-bean (R2, rice/Calopogonium muconoides-bean (R3 and corn

  8. Indução de resistência do mamoeiro à podridão radicular por indutores bióticos e abióticos Resistance induction to root rot in papaya by biotic and abiotic elicitors

    Directory of Open Access Journals (Sweden)

    Giltembergue Macedo Tavares

    2009-11-01

    Full Text Available O objetivo deste trabalho foi avaliar o potencial do uso de indutores de resistência bióticos e abióticos na redução da podridão radicular em mamoeiro. Mudas de mamoeiro foram pulverizadas com os fungicidas fosetil-Al, metalaxil e Mancozeb (2 g L-1, com os indutores abióticos fosfito de potássio (2,5 e 5 mL L-1, ácido salicílico 0,15 e 0,30%, Reforce (indutor comercial + ácido salicílico a 5%, acibenzolar-S-metil (ASM (0,15 e 0,30 g L-1, e com o indutor biótico Saccharomyces cerevisiae (3 e 6 mL L-1, três e seis dias antes da pulverização de 1 mL de suspensão de 10(5 zoósporos mL-1 de Phytophthora palmivora. Todos os tratamentos tiveram efeito no controle da podridão de raízes em relação à testemunha, com exceção do Reforce + ácido salicílico a 5% (3 mL L-1, seis dias antes da inoculação. Os tratamentos com ASM, com exceção da dosagem 0,15 g L-1 seis dias antes da inoculação, apresentaram resultados similares aos dos fungicidas metalaxil e Mancozeb. Plantas pulverizadas com ASM apresentaram aumento de atividade da peroxidase e beta-1,3-glucanase e maior concentração de lignina que a testemunha. No entanto, esses tratamentos não tiverem efeito sobre a atividade da quitinase. O ASM é um potencial indutor de resistência a P. palmivora em mamoeiro.The objective of this work was to evaluate the potential use of biotic and abiotic elicitors of resistance in the reduction of root rot in papaya. Papaya seedlings were sprayed with the fosetil-Al and metalaxyl and Mancozeb (2 g L-1 fungicides, with the potassium phosphite (2.5 and 5 mL L-1, salicylic acid 0.15 e 0.30%, Reforce (commercial product + salicylic acid 5%, acibenzolar-S-methyl (ASM (0.15 and 0.30 g L-1 abiotic elicitors, and with the Saccharomyces cerevisiae (3 and 6 mL L-1 biotic elicitor, applied three and six days before the inoculation with 1 mL of 10(5 zoospores mL-1 suspension of Phytophthora palmivora. All treatments were effective in controlling

  9. Propagation of Black Plum (Vitex donania Sweet) Using Stem and Root Cuttings in the Ecological Conditions of South-Benin

    OpenAIRE

    Sanoussi, A.; Ahoton, LE.; Odjo, T.

    2012-01-01

    The black plum is a multi-purpose tree well known to the rural and urban populations of tropical Africa. Its uses are well documented, but its regeneration possibilities have not yet been studied, despite the importance of this species. The objective of this study is to ensure that this tree can be propagated from other organs instead of seeds. In order to achieve this, a trial propagation, using stem and root cuttings, was conducted on two types of substrate: topsoil at the planting site (sa...

  10. New roots: Jamaican ontologies of blackness from Africa to the ghetto

    NARCIS (Netherlands)

    W. Modest; R. Jaffe

    2014-01-01

    This article explores contemporary ontologies of blackness in the Caribbean island of Jamaica. Approaching blackness as an ontological issue - an issue that pertains to the being, or the existence, of a category of people - we emphasize the spatial dimension of such ontologies. Drawing on Jamaican c

  11. 茄子白绢病、猝倒病、根腐病、黄萎病和枯萎病的识别与防治%ldentification and Control Methods of Eggplant Southern Blight, Damp-ing-off, Root Rot, Verticil-lium Wilt and Fusarium Wilt

    Institute of Scientific and Technical Information of China (English)

    高焕; 郑丹丹

    2012-01-01

    介绍了茄子白绢病、猝倒病、根腐病、黄萎病和枯萎病的危害症状、发病特点,并从农业措施、化学防治等方面总结了各病害的综合防治方法。%The symptom and disease characteristics of eggplant southern blight, damping-off, root rot, verticillium wilt and fusarium wilt were introduced. Then the integrated control methods were put forward, which contained measures of agricultural control, chemical control and so on.

  12. Biological control of Phytophthora root rot of avocato with microorganisms grown in organic mulches Controle biológico da podridão radicular de Phytophthora no abacateiro utilizando substratos orgânicos colonizados

    Directory of Open Access Journals (Sweden)

    Jefferson L. da S. Costa

    2000-10-01

    Full Text Available Organic mulches colonized with microbial biocontrol agents, termed bioenhanced mulches, were tested for their ability to reduce Phytophthora root rot of avocado (Persea americana Mill.. Benomyl-resistant mutants of Gliocladium virens (KA 230-1 and Trichoderma harzianum (KA 159.2 isolated from suppressive soils and selected as efficient antagonists of P. cinnamomi were evaluated for their ability to colonize different mulches under controlled laboratory conditions. Sudangrass and a coarse yardwaste were found to be better substrates than a fine yardwaste, woodwaste or rice hulls for biocontrol agents propagules production. The most suitable conditions for colonization were an optimum temperature of 24°C, a moisture content of 20% for sudangrass and 30% for the coarse yardwaste, and a continuous light exposure during a 15-day incubation period. In the greenhouse, fresh sudangrass and a coarse yardwaste colonized with G. virens and used as a surface mulch proved to be the best combination for reducing the population of P. cinnamomi in 4-liter pots containing artificially-infested soil. Healthy avocado roots made up 31-37% of the roots in the G. virens-mulch combinations compared to 0% healthy in infested controls after two months.Compostos orgânicos colonizados com agentes de controle microbiológico, então denominados compostos bioativados, foram testados quanto a sua habilidadade controlar à podridão radicular de Phytophtora no abacateiro (Persea americana Mill. Mutantes de Gliocladium virens (KA 230-1 e Trichoderma harzianun (KA 159-2 resistentes a benomyl recuperados de solos supressivos e selecionados como eficientes antagonistas à P. cinnamoni foram avaliados quanto à sua capacidade de colonizar diversos compostos orgânicos em condições de laboratório. O Capim Sudão e um Composto de Jardim de alta granulação demonstraram quanto à sua capacidade de multiplicar propágulos de agentes de biocontrole, serem superiores à um

  13. Identification of Fusarium Pathogens for Root Rot of Vicia faba L.at Seedling Stage in the Cold and Humid Regions of Gansu%甘肃高寒阴湿地区蚕豆苗期镰刀菌根腐病病原鉴定

    Institute of Scientific and Technical Information of China (English)

    侯思雯; 李敏权; 杨晓明; 杨发荣

    2011-01-01

    Isolation and culture of typical diseased plants of Viciafaba L. With fusarium root rot at seedling stage in the cold and humid regions of Linxia, 34 single-spore isolates of fusarium were obtained and identified, which belonged to Fusarium solani, Fusarium semitectum and Fusarium dimerum, respectively. Their pathogenicity was tested by using pot inoculation and.culture plate inoculation in laboratory. The results showed that all isolates had strong pathogenicity to seedlings of Viciafaba L., in which the Fusarium semitectum and Fusarium dimerum were the pathogens for root rot of Viciafaba L. At seedling stage is the first confirmed record.%对临夏高寒阴湿地区蚕豆苗期镰刀菌根腐病典型病株进行分离培养,共获得34个镰刀菌单孢菌株,经鉴定分别是茄镰刀菌(Fusarium solani)、半裸镰刀菌(Fusarium semitectum)和单隔镰刀菌(Fusarium dimerum).采用室内盆栽接种和平皿接种法测定致病性,结果表明,茄镰刀菌、半裸镰刀菌和单隔镰刀菌对蚕豆幼苗都有较强的致病性.其中,半裸镰刀菌和单隔镰刀菌是蚕豆苗期根腐病病原属首次报道.

  14. Reaction of arracacha genotypes to the root soft rot caused by Pectobacterium chrysanthemi Reação de genótipos de mandioquinha-salsa à podridão-mole das raízes causada por Pectobacterium chrysanthemi

    Directory of Open Access Journals (Sweden)

    Gilmar Paulo Henz

    2005-01-01

    Full Text Available The purpose of this paper was to screen thirty-two arracacha genotypes for their reaction to root soft rot. Twenty roots of each genotype were inoculated with two Pectobacterium chrysanthemi isolates in a randomized experiment (10 roots/isolate. After inoculation, roots were individually wrapped with PVC film and kept at 26ºC in closed plastic bags. Soft rot lesions were recorded after 36 hours and genotypes were grouped in four classes of susceptibility by cluster analysis: 10 were less susceptible, 16 intermediate, 3 susceptible and 3 very susceptible. All the tested arracacha genotypes showed only variation in the degree of susceptibility.O objetivo deste trabalho foi avaliar a reação de 32 genótipos de mandioquinha-salsa à podridão-mole das raízes. Vinte raízes de cada genótipo foram inoculadas com dois isolados de Pectobacterium chrysanthemi em um experimento casualizado (10 raízes/isolado. Após a inoculação, as raízes foram embaladas com filmes de PVC e mantidas a 26ºC em sacos de plástico. As lesões de podridão-mole foram avaliadas após 36 horas e os genótipos agrupados em quatro classes de suscetibilidade por análise de agrupamento: 10 foram menos suscetíveis, 16 intermediários, 3 suscetíveis e 3 muito suscetíveis. Todos os genótipos avaliados demonstraram apenas variação no grau de suscetibilidade.

  15. Antagonism of Trichoderma spp.to Fungi Caused Root Rot of Sophora tonkinensis%木霉菌对山豆根根腐病菌的拮抗作用

    Institute of Scientific and Technical Information of China (English)

    覃柳燕; 蒋妮; 唐美琼; 缪剑华; 李林轩

    2011-01-01

    目的:研究木霉菌对山豆根根腐病菌茄腐镰孢S9(Fusarium solani)的拮抗作用,探讨生物防治菌在防治中药材土传病害上的应用前景.方法:采用生长速度法、对峙培养法研究哈茨木霉H2(Trichoderma harsianum)、绿色木霉M6(Trichoderma viride)和康宁木霉K1(Trichoderma koningii)对山豆根根腐病菌S9的拮抗作用,并讨论了其作用机理.结果:发现H2、M6竞争优势显著,生长速度分别是S9的1.43~2.72倍和1.43~1.95倍;K1的空间竞争优势较弱,生长速度不如S9.3种木霉菌对S9均有不同程度的拮抗作用,其中,M6和H2对S9的拮抗作用较强,即使在提前3 d接入病原菌的情况下,M6和H2对S9的抑制率仍能分别达100%和82.35%,拮抗系数均达Ⅰ级;K1对S9的抑制率为46.36%,拮抗系数为Ⅳ级.在显微镜下观察到木霉菌通过缠绕、寄生等方式使S9发生菌丝断裂、缢缩、消解等现象.结论:哈茨木霉和绿色木霉作为生防菌在防治中药材土传病害上具有深入开发的前景.%Objective:To study the antagonism of Trichoderma spp. to fungi S9 ( Fusarium solani)which caused root rot of Sophora tonkinensis and discuss the further develop prospects of microbial biological control in soil-borne diseases on Chinese herbal medicines. Methods:Antagonism of H2 (Trichoderma harsianum ) , M6 (Trichoderma viride ) and K1 (Trichoderma koningii ) to Fusarium solani were researched by growth rate and confront culture. And their mechanisms were discussed. Results: H2 and M6 had obvious competitive advantage, the growth rate of which were 1.43 ~ 2. 72 times and 1.43 ~ 1.95 times as S9 respectively. The space competitive advantage of K1 was relatively weak ;the growth rate was slower than S9. The antagonism of three species of Trichoderma spp. to S9 was in varying degrees. The antagonism to S9 of M6 and H2 was better,the inhibition rate were 100% and 82. 35% respectively,even cultivated S9 for three days in advance. And their

  16. Severidade da podridão-radicular de Rhizoctonia do feijoeiro influenciada pela calagem, e pelas fontes e doses de nitrogênio Severity of Rhizoctonia root rot in beans influenced by liming, nitrogen sources and rates

    Directory of Open Access Journals (Sweden)

    Fabrício de Ávila Rodrigues

    2002-09-01

    Full Text Available Avaliou-se o efeito da calagem e de doses e fontes de N na severidade da podridão-radicular de Rhizoctonia (PRR em feijoeiro em condições controladas. No primeiro ensaio, utilizaram-se as doses de 0, 1,75, 2,25, 2,75, 3,25 e 3,75 g de calcário dolomítico por quilograma de solo. No segundo ensaio, os tratamentos constituíram um fatorial 2x6, ou seja: duas fontes de N (sulfato de amônio e nitrato de sódio e seis doses de N (0, 11, 16, 21, 26 e 31 mg kg-1 de solo. A acidez do material de solo usado no segundo ensaio foi corrigida com 1,75 g de calcário por quilograma de solo. Foram colocados 16 g de grãos de arroz infestados por R. solani em cada vaso com 1 kg de material de solo. Utilizou-se, em ambos os ensaios, o delineamento inteiramente casualizado, com cinco repetições. A severidade da PRR foi avaliada 25 dias após a emergência das plantas, atribuindo-se nota para cada planta de acordo com o tamanho das lesões formadas no hipocótilo. Os dados obtidos foram usados para calcular o índice de doença (ID, %. Foram obtidas equações lineares significativas que permitiram descrever as relações entre a calagem e fontes de N com a severidade da PRR. Houve um acréscimo de 32% no ID, em virtude das doses crescentes de calcário. Após a calagem, a aplicação de sulfato de amônio reduziu em 22% o ID, enquanto o nitrato de sódio o aumentou em 18%, com relação ao controle.The objective of this study was to determine the effects of liming, nitrogen sources and rates on the severity of Rhizoctonia root rot (RRR in beans under controlled conditions. In the first experiment, the soil was amended with 0, 1.75, 2.25, 2.75, 3.25 and 3.75 g of dolomitic lime per kilogram of soil. In the second experiment, the soil was fertilized with 0, 11, 16, 21, 26 and 31 mg N kg-1 of soil, using ammonium sulfate and sodium nitrate as N sources. For the second experiment, soil acidity was adjusted by applying 1.75 g of dolomitic lime per kilogram of

  17. Dynamics of Depletion and Replenishment of Water Storage in Stem and Roots of Black Spruce Measured by Dendrometers

    Science.gov (United States)

    Turcotte, Audrey; Rossi, Sergio; Deslauriers, Annie; Krause, Cornelia; Morin, Hubert

    2011-01-01

    In the short term, trees rely on the internal storage of water because it affects their ability to sustain photosynthesis and growth. However, water is not rapidly available for transpiration from all the compartments of the plant and the living tissues of the stem act as a buffer to preclude low water potentials during peaks of transpiration. In this paper, electronic dendrometers were used from mid-June to mid-September 2008 to compare the radius variations in stem and roots of black spruce [Picea mariana (Mill.) B.S.P.] in two sites of the boreal forest of Quebec, Canada, with different soil characteristics and water retention. The duration of the daily cycles was similar between sites and measurement heights but greater amplitudes of contraction and expansion were observed on the stem and in the site with the shallowest soil organic layer. The expansion phase had higher amplitudes and lasted longer than contraction. On average, the contraction phase occurred between 07:00 and 16:30 (legal time), while expansion lasted 14.5 h. The roots in the site with the deepest organic layer showed a wider variation in the onset of contraction, which could be as late as 13:00. The probability of observing the contraction phase depended on precipitation. With a precipitation 60% probability of observing contraction between 05:00 and 21:00, decreasing to 20% with precipitation >1.1 mm h−1. These findings demonstrated that the depth of the organic layer plays an important role in maintaining the internal water reserve of trees. The dynamics of water depletion and replenishment can modify the water potential of xylem and cell turgor during the enlargement phase, thus affecting radial growth. Changes in temperature and precipitation regime could influence the dynamics of internal water storage in trees growing on shallower and drier soils. PMID:22639583

  18. Effects of Fungal Root Pathogens on the Population Dynamics of Biocontrol Strains of Fluorescent Pseudomonads in the Wheat Rhizosphere

    OpenAIRE

    Mazzola, Mark; Cook, R. James

    1991-01-01

    The influences of Gaeumannomyces graminis var. tritici (which causes take-all of wheat), Rhizoctonia solani AG-8 (which causes rhizoctonia root rot of wheat), Pythium irregulare, P. aristosporum, and P. ultimum var. sporangiiferum (which cause pythium root rot of wheat) on the population dynamics of Pseudomonas fluorescens 2-79 and Q72a-80 (bicontrol strains active against take-all and pythium root rot of wheat, respectively) in the wheat rhizosphere were examined. Root infection by either G....

  19. Determination of caffeic acid in root and rhizome of Black cohosh (Cimicifuga racemosa (L. Nutt.

    Directory of Open Access Journals (Sweden)

    Zapala Karolina

    2014-06-01

    Full Text Available Cimicifuga racemosa, is a plant with a diverse and long history of medicinal use. Caffeic acid, bioactive compound, which often occurs with other polyphenols can influence the biological activity of this plant. The aim of our work was quantitative analysis of caffeic acid in roots and rhizomes of two varieties of C. racemosa. Analysis was performed by HPLC method. The extracts were separated on C18 reversed-phase column using mixture of methanol, water and formic acid (25:75:0.5 v/v/v as a mobile phase. The flow rate of eluent was 1.0 ml·min-1. The obtained validation parameters such as linearity, linear regression equation and precision expressed as a relative standard deviation were adequate for quantitative determination. Caffeic acid was found in all tested extracts. The highest total amount of caffeic acid was determined in C. racemosa var. racemosa (255.3 μg·g-1 while its concentration in C. racemosa var. cordifolia was significantly lower (213.0 μg·g-1.

  20. Differential expression of metallothionein type-2 homologues in leaves and roots of Black pepper (Piper nigrum L

    Directory of Open Access Journals (Sweden)

    Susan M. Alex

    2008-01-01

    Full Text Available Black pepper (Piper nigrum L., member of the family Piperaceae is indigenous to India and is one of the most widely used spices in the world. In this paper we report the results of our attempts to identify a set of genes differentially expressed in the leaves of Piper nigrum, which could facilitate targeted engineering of this valuable crop. A PCR-based Suppression Subtractive Hybridization (SSH technique was used to generate a leaf-specific subtracted cDNA library of Piper nigrum. A tester population of leaf cDNA was subtracted with a root derived driver cDNA. The efficiency of subtraction was confirmed by PCR analysis using the housekeeping gene actin. On sequence analysis, almost 30% of the clones showed homology to metallothionein type-2 gene. The predominance of metallothionein transcripts in the leaf was further confirmed using Real-Time PCR analyses and Northern blot. The possible role of metallothionein type-2 homologues in the leaf is discussed along with the feasibility of using SSH technique for identification of more number of tissue-specific genes from Piper nigrum.

  1. Brown rot on nuts of Castanea sativa Mill: an emerging disease and its causal agent

    OpenAIRE

    Maresi G; Oliveira Longa CM; Turchetti T

    2013-01-01

    The quality and quantity of nut production are fundamental to the economic viability of chestnut cultivation, yet recent reports indicate that severe damage due to moulds represents a significant problem for growers. We carried out an investigation of the agents of chestnut rot and internal fruit damage in three orchards in Italy. Black and brown rot, as well as insect damage, were found in all the areas examined. Brown rot appeared to be the main cause of damage, affecting 8% to 49% and 2% t...

  2. Characterization of a Brown Rot Fungus Isolated from Dwarf Flowering Almond in Korea

    OpenAIRE

    Shim, Myoung Yong; Jeon, Young Jae; Kim, Seong Hwan

    2007-01-01

    The fruits showing brown rot symptom on dwarf flowering almond were found in Gongju, Chungchungnam-Do in Korea in July 2005. Small water-soaked lesions on the fruits were initiated, and gradually developed to soft rot covered with gray conidia. Then the diseased fruits were shrunk and became grayish-black mummies. A fungus was isolated from the diseased fruit and its morphological, cultural and molecular genetic characteristics were investigated. Typical blastospores of Monilinia spp. were ob...

  3. Rhizopus Soft Rot on Lily Caused by Rhizopus oryzae in Korea

    OpenAIRE

    Soo-Sang Hahm; Gye-Wan Hong; Byung-Ryun Kim; Kwangseop Han; Takyong Choi; Yungyu Nam; Seunghun Yu

    2014-01-01

    Rhizopus soft rot of lily (Lilium longiflorum) caused by Rhizopus oryzae was observed in the experimental field in Taean Lily Experiment Station in Korea, 2012. The typical symptoms were water-soaked lesions on bottom stem and leaf rot. The lesion rapidly expanded and the plant was softened totally. The fungus grew vigorously at an optimum temperature (25oC) and brownish colony and black sporangia were formed on potato dextrose agar medium. Sporangiophores formed on end of sporang...

  4. Thermal control of some post-harvest rot pathogens of Irish potato (solanum tuberosum l.)

    OpenAIRE

    Salami Olusola Abiodun; Popoola Omololu Olumide

    2007-01-01

    Thermal control effect on the incidence of some post-harvest rot pathogens of Solanum tuberosum (potato) was investigated in this study. Three cultivars of potato tuber whose local names are, Patiska, Mai Bawondoya and Nicola were used for the study. Five pathogenic fungi viz: Botryodiplodia theobromae, Fusarium redolens, Fusarium oxysporum, Penicillium sp. and Rhizopus oryzae associated with post harvest storage rot of root-tubers, were isolated from diseased potatoes. Among the three specie...

  5. Brown rot on nuts of Castanea sativa Mill: an emerging disease and its causal agent

    Directory of Open Access Journals (Sweden)

    Maresi G

    2013-07-01

    Full Text Available The quality and quantity of nut production are fundamental to the economic viability of chestnut cultivation, yet recent reports indicate that severe damage due to moulds represents a significant problem for growers. We carried out an investigation of the agents of chestnut rot and internal fruit damage in three orchards in Italy. Black and brown rot, as well as insect damage, were found in all the areas examined. Brown rot appeared to be the main cause of damage, affecting 8% to 49% and 2% to 24% of nuts collected from the ground and from burrs, respectively. With respect to morphology and DNA sequencing analyses, fungal isolates obtained from brown rot were homologous with Gnomoniopsis sp. obtained from Dryocosmus kuriphilus (Yasumatsu galls and with Gnomoniopsis castanea and Gnomoniopsis smithogilvyi described on chestnut in Italy and Australia, respectively. The same fungus was also isolated from the bark of one- and two-years-old healthy shoots at each site, supporting the endophytic behaviour of this rot agent. Brown rot symptoms on nuts associated with Gnomoniopsis sp. corresponded with those previously described by several authors and referred to as Phoma or Phomopsis endogena, suggesting a relationship between these fungi and Gnomoniopsis sp. It is to notice that the escalation of brown rot damage in Italy followed several periods of drought and probably the recent invasion of D. kuriphilus, both stress factors for chestnut trees.

  6. DEVELOPMENT AND SUPPRESSION OF GRAPEVINE BLACK FOOT CAUSED BY ILYONECTRIA RADICICOLA

    Directory of Open Access Journals (Sweden)

    Khadeeja A. Saido

    2013-04-01

    Full Text Available Present study investigated the development and suppression of grapevine black foot using a highly virulent strain of Ilyonectria radicicola during 2010-2012 after its widespread outbreak in Duhok - Iraq since 2008. Inoculated roots showed distinctive symptoms of sunken necrotic lesions with internal black streaking of rootstocks. Production of mycelial mass (in vitro was higher at pH 5.0 resulting in 57% severity of foot rot compared to 46.16% at pH 7.0. In general, Kamali cv. was the most susceptible cultivar with 59.29% of stubby root growth affected compared to 53.32% and 40.83% on Rashmew and Taefi cvs. respectively. Wounding roots of a susceptible cultivar developed the conspicuous symptoms of black foot rot with a severity of 90%. Increasing the conidial inoculum was essential for severe infection development to more than 62%, whereas interaction between inoculation and wounding of roots increased lesion severity to 80.09%. However, acidic pH significantly enhanced disease progression on inoculated vine cuttings to 84.41% compared to 40% at neutral pH. Unfortunately, inoculum of Ilyonectria radicicola was not suppressed significantly even with fungicide application and continued its damage on Rashmew cv. Resulting in disease severity of 23.70% . More than 25% of the inoculated vines grown in amendments of Trichoderma harzianum and farmyard manures were infected compared to 14.80% and 20.73% of the non-inoculated. Exclusion of fungal inoculum improved the plant vigours as measured by dry weight and shoot growth, whereas significant stimulation of root growth were evidenced in the amended treatments particularly those with farmyard manures and fungicides. 

  7. Common roots: a contextual review of HIV epidemics in black men who have sex with men across the African diaspora.

    Science.gov (United States)

    Millett, Gregorio A; Jeffries, William L; Peterson, John L; Malebranche, David J; Lane, Tim; Flores, Stephen A; Fenton, Kevin A; Wilson, Patrick A; Steiner, Riley; Heilig, Charles M

    2012-07-28

    Pooled estimates from across the African diaspora show that black men who have sex with men (MSM) are 15 times more likely to be HIV positive compared with general populations and 8·5 times more likely compared with black populations. Disparities in the prevalence of HIV infection are greater in African and Caribbean countries that criminalise homosexual activity than in those that do not criminalise such behaviour. With the exception of US and African epidemiological studies, most studies of black MSM mainly focus on outcomes associated with HIV behavioural risk rather than on prevalence, incidence, or undiagnosed infection. Nevertheless, black MSM across the African diaspora share common experiences such as discrimination, cultural norms valuing masculinity, concerns about confidentiality during HIV testing or treatment, low access to HIV drugs, threats of violence or incarceration, and few targeted HIV prevention resources. PMID:22819654

  8. Biomethanation of white rotted and brown rotted rice straw

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, A.; Bhattacharyya, B.C. [Chemical Engineeringg Dept., Biotechnology Unit, IIT Kharagpur, (India)

    1999-04-01

    Biomethanation of white rotted and brown rotted rice straw was taken for the present investigation and their efficiency on biomethanation has been tested. Rice straw was treated with white rot fungus Phanerochaete chrysosporium (P{sub C}) and brown rot fungus Polyporus ostreiformis (P{sub O}). Biogas and methane production was increased by about 34.73% and 46.19% in P{sub C}-treated straw and 21.12% and 31.94% in P{sub O}-treated straw respectively. VFA production has also been increased in P{sub C} and P{sub O} treated straw compared to control straw which were 76.73% and 30.69% respectively. Reduction of COD has also been found during biomethanation. The rate of reduction of COD during the initial period of digestion was 59.01%, 55.55% and 26.00% in P{sub C}-treated, P{sub O}-treated and control straw respectively after 21 days of digestion. (orig.) With 12 figs., 3 tabs., 14 refs.

  9. Research on Forma Specialis of Fusarium solani Causing Root Rot of Tea Cutting Seedling and Discussion of Relevant Issues%茶扦插苗根腐性苗枯病菌茄镰孢霉专化型研究及相关问题的商榷

    Institute of Scientific and Technical Information of China (English)

    赖传雅; 赖传碧; 曾凡凯; 韦少敏; 李复新; 周国辉

    2012-01-01

    茶扦插苗根腐性苗枯病是广西一些茶圃的常见病害,严重影响茶苗出圃.明确该病病原菌分类地位可以为病害防治提供理论依据.为此,作者从桂北茶扦插苗圃中随机采得18株病株标本,分离出镰孢霉纯菌株16株,单孢菌纯系培养18株(GF01 ~ GF18号).参照BOOTH镰刀菌分类鉴定标准,对代表性单孢菌株GF08号的培养菌进行了形态鉴定;以蘸根法和土壤伤根法测试其致病性,同时在12科22种植物上进行接种试验.结果表明,该菌与茄镰孢霉[ Fusarium solani( Mart.)Sacc.]形态特征一致,经柯赫氏法则验证确定其为茶扦插苗根腐性苗枯病的病原菌.该菌除侵染山茶科的福云六号大叶种和白毛茶外,对其余11科20种植物均不致病.因此鉴定该菌为茄镰孢霉一新专化型:Fusarium solani (Mart.) Sacc.f sp.theae Chuan-Ya Lai et Chuan-Bi Lai.%Root rot of tea cutting seedling is a common and serious disease occurred in some tea nurseries in Guangxi, China. Determination of taxonomy status of the pathogen can provide theoretic basis for the disease control. So 18 diseased samples were collected from the tea nurseries in north Guilin of Guangxi, and pure cultures of 16 Fusarium isolates and monospore cultures of 18 strains (GF01 ~ GF18) were obtained. Typical strain GF08 was identified based on BOOTH's species concept for Fusarium and tested for pathogenicity by dipping seedling roots and micro injuring roots methods. Twenty-two plant species of 12 families were inoculated with strain GF08. The results showed that the morphological characters of strain GF08 was consistent with Fusarium solani (Mart. ) Sacc and its pathogenicity was confirmed by Koch's postulates. Except for Camellia sinensis and C. sinensis (Theaceae) , the pathogen did not infect other 20 plant species of 11 families. Therefore, the pathogen of root rot of tea cutting seedling was identified as a new forma specialis that was Fusarium solani ( Mart. ) Sacc

  10. Allelopathic effect of black mustard tissues and root exudates on some crops and weeds Efeito alelopático de tecidos de mostarda-preta e exsudatos da raiz de algumas culturas e plantas daninhas

    OpenAIRE

    E Al-Sherif; A.K. Hegazy; N.H. Gomaa; Hassan, M O

    2013-01-01

    Laboratory and greenhouse experiments were conducted to evaluate the phytotoxic effect of black mustard extracts and root exudates on two crops: Trifolium alexandrinum and Triticum aestivum, and two weeds: Phalaris paradoxa and Sisymbrium irio. The seeds were treated with aqueous and ethanolic extracts and chloroform for eight days, or subjected to root exudates of just harvested mustard in a greenhouse for five weeks. High-performance liquid chromatography (HPLC) was used to quantify phytoto...

  11. The Phenotype Evolution and Transfer Breeding of Black Rot Resistance in Somatic Hybrids Between Cauliflower and Black Mustard%花椰菜—黑芥体细胞杂种的性状演变和对黑腐病抗性的转育

    Institute of Scientific and Technical Information of China (English)

    张洁; 王桂香; 韩硕; 严红; 宗梅; 郭宁; 刘凡

    2016-01-01

    以对黑腐病(Black rot)感病的花椰菜(Brassica oleraceaL.var.botrytisL.,2n=18,CC)‘Korso’和抗病的黑芥(B.nigra,black mustard,2n=16,BB)‘G1/1’的体细胞杂种(简称PFCN,protoplast fusion of cauliflower and Brassica nigra)高代自交及回交后代为材料,根据表型特征将其分为4大类:性状介于花椰菜和黑芥之间的中间型材料(M)、向花椰菜过渡的过渡型(M-K)、偏花椰菜型(-K)和花椰菜型(K).连续5年的黑腐病人工接种鉴定结果显示:‘Korso’的病情指数在44 ~ 57之间,表现为耐病到感病;‘G1/1’在12 ~ 32之间,表现为抗病,从M、M-K、-K至K型,杂种后代病情指数总体上呈逐渐升高的趋势,其中M型和M-K型材料表现为高抗至抗病,-K型材料表现为抗病至耐病,K型材料表现为耐病.对2014年的15份典型-K至K型材料进行了形态演变及黑腐病抗性变化追溯:总体上,偏花椰菜的形态转变发生在S1BC4、55、S1BC3和BC3(S为自交,BC为回交)世代中,伴随着形态的转变,黑腐病病情指数急剧升高;同一年中来源相同或者相近的株系病情指数相差不多.2015年进一步对2014年25个单株的自交后代进行黑腐病抗病性跟踪鉴定:整体上病情指数呈下降趋势,仅少数株系表现上升;来源相同的衍生株系变化趋势几乎一致,且差异不大,说明这些材料系内对黑腐病抗病性逐年趋于稳定.目前获得了6份相对于受体亲本‘Korso’表现出了对黑腐病抗性显著提高的材料:PFCN14-15-4.1、PFCN14-15-5.1、PFCN 14-29-1.1和PFCN 14-29-1.2,连续3年病情指数呈下降趋势,并最终稳定在30左右;PFCN14-14-1.1和PFCN14-14-1.2则连续6年保持在20 ~ 38之间.

  12. Growth Inhibition of Cocoa Pod Rot Fungus Phytophthora palmivora byPseudomonas fluorescence and Bacillus subtilis bacteria

    OpenAIRE

    Sakti Widyanta Pratama; Sri Sukamto; Lis Nur Asyiah; Yeni Vida Ervina

    2013-01-01

    Black pod disease caused by Phytophthora palmivorafungus is one of the important diseases on cocoa crop. Pod rot is the most important disease because it may cause loss of cocoa pod. Until now, the fungal pathogen of cocoa black pod disease is still a crucial problem and there is no fungicide that is really effective against the disease. One alternative to control the cocoa black pod disease is by using biological agents as biofungicide, including utilizing Pseudomonas fluorescenceand Bacillu...

  13. Occurrence of Soft Rot on Raspberry (Rubus crataegifolius) Caused by Rhizopus oryzae in Korea

    OpenAIRE

    Jin-Hyeuk Kwon; Dong-Wan Kang; Jae-Uk An; Okhee Choi; Youn-Sig Kwak

    2011-01-01

    Soft rot disease on Raspberry (Rubus crataegifolius Bunge) was observed in sale boxes at Jinju CityWholesale Market of Agricultural Products in June 2010. The infected fruits were rapidly water-soaked,softened, black and eventually rotted. The colonies on the infected fruits were white to light brown, formednumerous sporangiospores. Optimum temperature for the mycelial growth of the causal fungus on PDA was30oC and growth was still apparent at 37oC. Sporangia were globose, white at early and ...

  14. Microbial antagonism as a potential solution for controlling selected root pathogens of crops

    Science.gov (United States)

    Cooper, Sarah; Agnew, Linda; Pereg, Lily

    2016-04-01

    Root pathogens of crops can cause large reduction in yield, however, there is a limited range of effective methods to control such pathogens. Soilborne pathogens that infect roots often need to survive in the rhizosphere, where there is high competition from other organisms. In such hot spots of microbial activity and growth, supported by root exudates, microbes have evolved antagonistic mechanisms that give them competitive advantages in winning the limited resources. Among these mechanisms is antibiosis, with production of some significant antifungal compounds including, antibiotics, volatile organic compounds, hydrogen cyanide and lytic enzymes. Some of these mechanisms may suppress disease through controlling the growth of root pathogens. In this project we isolated various fungi and bacteria that suppress the growth of cotton pathogens in vitro. The pathogen-suppressive microbes were isolated from cotton production soils that are under different management strategies, with and without the use of organic amendments. The potential of pathogen-suppressing microbes for controlling the black root rot disease, caused by the soilborne pathogen Thielaviopsis basicola, was confirmed using soil assays. We identified isolates with potential use as inoculant for cotton production in Australia. Having isolated a diverse group of antagonistic microbes enhances the probability that some would survive well in the soil and provide an alternative approach to address the problem of root disease affecting agricultural crops.

  15. 葡萄白腐病、炭疽病、黑痘病、霜霉病和白粉病的识别与防治%ldentification and Control of White Rot, Anthrac-nose, Black Pox, Downy Mildew and Powdery Mildew of Grape

    Institute of Scientific and Technical Information of China (English)

    李婷

    2013-01-01

    Damage symptom and onset characteristics of white rot, anthracnose, black pox,downy mildew and powdery mildew of grape were introduced. More-over, the comprehensive prevention measures were proposed mainly on pre-vention.These diseases should be con-trolled on the basis of enhancing culti-vation management,improving diseasere-sistant capacity of plants, and chemicals should be applied timely at the initial infection stage .The study provided a support for relieving damages of grape diseases, improving yield and quality of grape.%介绍了葡萄白腐病、炭疽病、黑痘病、霜霉病和白粉病的危害症状及发病特点,提出防治这些病害应以预防为主,在加强栽培管理、增强树势、提高树体抗病能力的基础上,在发病初期及时施用化学药剂,以达综合防治的目的。为减轻病害危害,提高葡萄的产量和品质提供了一定的依据。

  16. 利用辣椒疫霉培养滤液体外筛选胡椒抗瘟病无性系研究%In vitro Selection of Black Pepper (Piper nigrum Linn.) Somaclones Resistant to Foot Rot Using Culture Filtrate of Phytophthora capsici

    Institute of Scientific and Technical Information of China (English)

    刘进平; 郑成木

    2004-01-01

    Based on shoot-tip multiplication technique, the application of in vitro selection of black pepper somaclones resistant to foot rot disease caused by fungus Phytophthora capsici was carried out using a large-leaf variety Daye (Lampong Type) which is widely cultivated in Hainan but highly susceptible to P. capsici as explant resources. The results demonstrated that sterilization methods significantly influenced on the toxicity of the culture filtrate of P. capsici. The fungal filtrate toxicity could be maintained using filtrate sterilization by addition of the fungal filtrate into selective medium instead of autoclave sterilization. The survival rate of shoot tips and multiple shoots decreased with the increasing concentrations of the fungal culture filtrate. Some cultures blackened and died finally, and some formed calli or remained dormant. After 2 subcultures onto the same selective medium,microshoots were rooted in vitro and transferred to the greenhouse conditions for screening the resistance to fungus P. capsici. The plants exhibited no external symptoms of the disease during three successive times of resistance assay once two weeks were considered to be resistant. As the concentrations of fungal culture filtrate increased, the total number of regenerated plants obtained declined but the frequencies of plants resistant to P. capsici increased. 1 (1.54%), 4 (20.00%) and 3 (42.86%) disease resistant somaclonal variants were obtained at concentration of 25%, 50% and 75% fungal culture filtrate as selective agents, respectively, with the total number of 8 plants resistant to P. capsici.%在胡椒(Piper nigrum Linn.)茎尖丛生增殖技术的基础上,以印尼大叶种"Lampong Type"无菌实生苗作外植体源,利用辣椒疫霉(Phytophthora capsici)培养滤液对胡椒茎尖及其增殖形成的丛生芽进行体外选择.辣椒疫霉培养滤液的不同灭菌方法对辣椒疫霉培养滤液的毒性影响显著,过滤灭菌方式可以保持辣椒疫霉

  17. 生物有机肥对防治山药根茎腐病和促进山药生长的研究%Effects of Bio-organic Fertilizer on Controlling Root and Stem Rot and Promoting Growth of Yam

    Institute of Scientific and Technical Information of China (English)

    马田田; 杨兴明; 沈其荣; 陈巍

    2013-01-01

    为了探讨生物有机肥(BOF)对山药根茎腐病的防治效果和促生效果,在山药根茎腐病重发地块进行了田间小区试验.结果表明:施用生物有机肥的处理Tl(CK+450 kg/hm2 BOF)、T2(CK+750 kg/hm2 BOF)和T3(CK+1050kg/hm2 BOF)与CK相比,山药根茎腐病病斑的长度分别减小了65.1%、77.2%、78.0%,病斑所占的比例分别下降了67.6%、80.0%、81.7%,对山药根茎腐病有很好的防治效果;山药块茎的鲜重分别增加了15.2%、32.0%、37.1%,块茎长度分别增加了6.0%、11.3%、19.5%,块茎茎粗分别增加了10.9%、23.6%、50.9%,山药产量提高了15.3%、32.2%、37.3%;T1、T2和T3与CK相比,细菌的数量分别增加1.04、1.31、1.41倍、放线菌的数量分别增加1.09、1.18、1.71倍,真菌的数量分别减少了21.9%、46.9%、50.0%,从而改善土壤微生态环境.施用生物有机肥不仅可以明显减少山药根茎腐病的发生,同时对山药有较强的促生效果,具有广阔的应用前景.%Root and stem rot of yam is a main soil-borne disease which severely inhibits the development of yam production industry in China.A field plot experiment was carried out to study the effects of bio-organic fertilizer on the suppression on root and stem rot of yam and plant growth.The results indicated that bio-organic fertilizer could control root and stem rot of yam by reducing the length and the percentage of disease spot.The length of the disease spot of yam tuber in the treatments T1 (CK+450 kg/hm2 BOF),T2 (CK+750 kg/hm2 BOF) and T3 (CK+1050 kg/hm2 BOF) were reduced by 65.1%,77.2% and 78.0%,the percentage of disease spot were reduced by 67.6%,80.0% and 81.7% respectively compared with CK.Bio-organic fertilizer could promote the growth of yam,compared with CK the fresh weight of yam tuber in the treatments T1,T2and T3 were increased by 15.2%,32.0% and 37.1%,the length of yam tuber were increased by 6.0%,11.3% and 19.5

  18. Stem Rot on Adzuki Bean (Vigna angularis) Caused by Rhizoctonia solani AG 4 HGI in China.

    Science.gov (United States)

    Sun, Suli; Xia, Changjian; Zhang, Jiqing; Duan, Canxing; Wang, Xiaoming; Wu, Xiaofei; Lee, Suk-Ha; Zhu, Zhendong

    2015-03-01

    During late August and early September 2011, stem rot symptoms were observed on adzuki bean plants (Vigna angularis) growing in fields located in Beijing and Hebei Province, China, respectively. In this study, four isolates were obtained from infected stems of adzuki bean plants. Based on their morphology, and sequence and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses of the ribosomal DNA internal transcribed spacers (rDNA-ITS) region, the four isolates were identified as Rhizoctonia solani in anastomosis group (AG) 4 HGI. Pathogenicity tests showed that all isolates were strongly pathogenic to adzuki bean and resulted in serious wilt symptoms which was similar to observations in the fields. Additionally, the isolates infected several other crops and induced related rot on the roots and basal stems. To our knowledge, this is the first report of Rhizoctonia solani AG 4 HGI causing stem rot on adzuki bean. PMID:25774112

  19. Tolerância de híbridos e de clones de porta-enxertos de citros à infecção de raízes por Phytophthora nicotianae Tolerance of hybrids and rootstock clones of citrus to root rot infection caused by Phytophthora nicotianae

    Directory of Open Access Journals (Sweden)

    Herculano P. Medina Filho

    2004-04-01

    Full Text Available Estudaram-se clones de porta-enxertos de citros (Citrus spp., híbridos e genitores quanto à tolerância das raízes a Phytophthora nicotianae através de inoculações em substrato de argila expandida. Investigaram-se progênies nucelares dos clones Poncirus trifoliata 'Rich 16-6', citrumelo 'Swingle' (C. paradisi x P. trifoliolata , tangerinas 'Cleópatra' (Citrus reshni e 'Suen Kat' (C. sunki, limão'Volkameriano' (C. volkameriana, dos genitores tangerina 'Sunki' (C. sunki (S, limão 'Cravo' (C. limonia (C, laranja 'Azeda' (C. aurantium ((A, Poncirus trifoliata 'Davis A' (T, e progênies nucelares de híbridos entre eles, totalizando 2303 plântulas. Avaliou-se a taxa de sobrevivência, redução de raízes e partes aéreas, peso de raízes e de partes aéreas, diâmetro do caule e altura, comparando-se plântulas inoculadas e não inoculadas. Atribuíram-se também notas subjetivas para volume de raízes, enfolhamento, coloração das folhas e altura. Desenvolveu-se um índice total de redução (ITR baseado na taxa de sobrevivência e nos parâmetros mencionados. Mostraram-se altamente tolerantes os trifoliatas 'Davis A' e 'Rich 16-6', o citrumelo 'Swingle', três híbridos TxS, dois SxT e dois SxA, com ITR 80%. A metodologia de inoculação e avaliação discriminou com precisão progênies nucelares dos clones e dos híbridos, evidenciando o potencial de seleção principalmente dos híbridos SxT e recíprocos.Clones of citrus rootstocks, hybrids and their parents were evaluated for tolerance to root rot incited by Phytophthora nicotianae. It were evaluated 'Rich 16-6' Trifoliate orange (Poncirus trifoliata, citrumelo 'Swingle' (C. paradisi x P. trifoliolata, 'Cleopatra' (Citrus reshni and 'Suen Kat' (C. sunki mandarins, 'Volkamer' lemon (C. volkameriana, the parents 'Sunki' mandarin (C. sunki (S, Rangpur lime (C. limonia (C, Sour orange (C. aurantium (A and 'Davis A' Trifoliate orange (T, and the nucellar progenies of hybrids between

  20. Caracterização de isolados de Phytophthora drechsleri, agente causal da podridão mole de raízes de mandioca Characterization of Phytophthora drechsleri, the causal agent of cassava soft root rot

    Directory of Open Access Journals (Sweden)

    Maria de Fátima S. Muniz

    2006-04-01

    Full Text Available O presente trabalho teve como objetivo caracterizar nove isolados de Phytophthora sp. obtidos de mandioca (Manihot esculenta, através da morfologia e morfometria das estruturas propagativas e crescimento micelial em diferentes temperaturas e avaliar sua patogenicidade. Os esporângios produzidos em extrato de solo não esterilizado mostraram-se ovóides, não papilados, persistentes, formados em esporangióforos não ramificados ou em simpódio, com dimensões de 24,6 - 57,4 µ x 14,8 - 37,7 µm e relação comprimento/largura de 1,0 - 2,6. Os clamidósporos foram raros. Os oósporos obtidos em cultura monospórica em V8 ágar eram apleuróticos, com 13,1 - 34,4 µm de diâmetro. Oogônios mostraram-se esféricos e mediram 19,7 - 41,0 µm de diâmetro; anterídios anfígenos, com dimensões de 8,2 - 24,6 µm x 8,2 - 19,7 µm. O maior diâmetro das colônias ocorreu a 25 ºC em V8 ágar. Os isolados patogênicos às plantas e raízes destacadas de mandioca inoculados foram identificados como Phytophthora drechsleri.Nine Phytophthora isolates from cassava (Manihot esculenta were characterized based on morphology and morphometry of propagative structures, growth at 10, 15, 20, 25, 30 and 35 ºC, and by evaluating its pathogenicity. Sporangia produced on nonsterile soil extract were ovoid, nonpapillate and persistent, formed in a sympodium or unbranched sporangiophores, 24.6 to 57.4 µm long x 14.8 to 37.7 µm wide, and length-breadth ratio was 1.0 - 2.6. Chlamydospores were rarely observed. Oospores produced in single spore culture on V8 agar medium were aplerotic, and 13.1 to 34.4 µm in diameter. Antheridia were amphigynous, measuring 8.2 - 24.6 µ x 8.2 - 19.7 µ ; oogonia ranged from 19.7 to 41.0 µm in diameter. Culture growth was greatest at 25 ºC in V8 agar medium. The isolates that were pathogenic to plants and detached roots of cassava were identified as Phytophthora drechsleri Tucker.

  1. Breeding for fruit rot resistance in Vaccinium macrocarpon

    Science.gov (United States)

    The cranberry fruit rot complex can cause severe crop loss and requires multiple fungicide applications each year. To identify sources of fruit rot resistance, fungicides were withheld from our germplasm collection in 2003 and 2004 and the collection was rated for fruit rot (1-5 scale, 1=no rot, 5=...

  2. Caracterização de isolados de Xanthomonas campestris pv campestris de sistemas de produção orgânico e reação de brássicas à podridão-negra Characterization of strains of Xanthomonas campestris pv campestris from organic farming systems and reaction of brassicas to black rot

    Directory of Open Access Journals (Sweden)

    Liliana Andréa dos Santos

    2008-12-01

    .3%, resistance to amoxicilin (70%, gentamicin (40.0% and norfloxacin (45.5% and medium sensitivity (44.4% or resistance (44.4% to neomycin. Fifty-five strains of Xcc were resistant to copper sulfate at 50 mg mL-1 and all of them to 200 mg mL-1; 92.22% of the strains showed esterase activity. Strains were grouped in seven similarity groups by the Euclidean analysis-single linkage. The reaction of 14 genotypes of brassicas to strain "B21" of Xcc was also studied. The genotypes significantly differed among them in relation to incubation period, incidence and disease severity. The highest disease severity was recorded on broccoli "Ramoso", cauliflower "Bola de Neve" and "Piracicaba de Verão", and cabbage "Chato de Quintal", classified as highly susceptible to black rot. The Chinese cabbage hybrids "AF 70", "AF 72", "AF 69" and "AF 66" were highly resistant to black-rot, while broccolis "Ramoso" and "Piracicaba Precoce", cauliflower "Piracicaba de Verão" and "Híbrido Cindy" and cabbage "60 Dias" showed intermediate resistance.

  3. Assessment of Production of Extracellular Enzymes by Trichoderma spp. For Control of Soybean Root Rot Pathogens (Fusarium oxysporum,Rhizoctonia solani)%木霉菌(胞外水解酶)拮抗大豆根腐病病原菌的机制研究

    Institute of Scientific and Technical Information of China (English)

    邵红涛; 许艳丽

    2006-01-01

    The role of extracellular enzymes by Trichoderma MM35 for control of soybean root rot pathogens(Fusarium oxysporum , Rhizoctonia solani) was assessed in vitro and in vivo. Detective levels of hydrolytic extracellular enzymes were recorded by Trichoderma MM35 using dried F. oxysporum mycelium as C-source in vitro or fresh F. oxysporum mycelium or fresh R.solani mycelium in vivo was found that there were significant increases in chitinase activities by Trichoderma MM35 in soil with inoculation of F. oxysporum. Soil infested with Trichoderma MM35 had significantly elevated chitinase and β-1,3-glueanase activities in presence of R. solani as compared to R. solani control.%通过室内试验与温室试验研究了具有生防能力的木霉菌株Trichoderma MM35所分泌的胞外水解酶在拮抗大豆根腐病病原菌(F.oxysporum、R.solani)中的作用.试验结果表明:以病原菌F.oxysporum烘干的菌丝体作唯一碳源,可以诱导Trichoderma MM35分泌几丁质酶、β-1,3-葡聚糖酶.β-1,3-葡聚糖酶高水平诱导表达在前,几丁质酶诱导表达在后.土壤中接种Trichoderma MM35、F.oxysporum和R.solani之后都能够检测到几丁质酶、β1,3-葡聚糖酶活性.向有病原菌F.oxysporum的土壤中接种Trichoderma MM35,土壤中几丁质酶活性能够显著升高.向有病原菌R.solani的土壤中接种Trichoderma MM35,土壤中的几丁质酶、β-1,3-葡聚糖酶活性都显著升高.

  4. Rhizopus Soft Rot on Pear (Pyrus serotina) Caused by Rhizopus stolonifer in Korea

    OpenAIRE

    Kwon, Jin-Hyeuk; Lee, Chan-Jung

    2006-01-01

    Rhizopus soft rot caused by Rhizopus stolonifer occurred on pears (Pyrus serotina) in the Jinju City Agricultural Products Wholesale Market in Korea from 2004 to 2005. The infection usually started from wounds due to cracking at harvest time. The lesions started as water-soaked, rapidly softened, then gradually expanded. The mycelia grew vigorously on the surface of the fruits and formed stolons. Colonies on potato dextrose agar at 25℃ were white cottony to brownish black. Sporangia were glob...

  5. De Novo Sequencing, Assembly, and Analysis of the Root Transcriptome of Persea americana (Mill.) in Response to Phytophthora cinnamomi and Flooding

    OpenAIRE

    Reeksting, Bianca J.; Coetzer, Nanette; Mahomed, Waheed; Engelbrecht, Juanita; van den Berg, Noëlani

    2014-01-01

    Avocado is a diploid angiosperm containing 24 chromosomes with a genome estimated to be around 920 Mb. It is an important fruit crop worldwide but is susceptible to a root rot caused by the ubiquitous oomycete Phytophthora cinnamomi. Phytophthora root rot (PRR) causes damage to the feeder roots of trees, causing necrosis. This leads to branch-dieback and eventual tree death, resulting in severe losses in production. Control strategies are limited and at present an integrated approach involvin...

  6. Isolamento e seleção de fungos causadores da podridão-branca da madeira em florestas de Eucalyptus spp. com potencial de degradação de cepas e raízes Isolation and screening of wood white rot fungi from Eucalyptus spp. forests with potential for use in degradation of stumps and roots

    Directory of Open Access Journals (Sweden)

    Sandra Kunieda de Alonso

    2007-02-01

    Full Text Available Este trabalho objetivou isolar fungos causadores da podridão-branca da madeira, a partir de basidiocarpos e de fragmentos de madeira de eucalipto coletados em várias regiões do país, bem como testar seu potencial de degradação de cepas e raízes mortas em plantios comerciais de eucalipto, após o corte raso. Para o isolamento dos fungos foi desenvolvido um meio de cultura de serragem de eucalipto-ágar. Dentre 292 isolados obtidos e submetidos ao teste de Bavendamm, 144 foram classificados como causadores de podridão-branca, capazes de produzir fenoloxidases. Dentre as nove relações C/N testadas, observou-se uma tendência de ocorrer maior degradação de cavacos naquelas iguais a 60 : 1, 200 : 1 e 300 : 1. Utilizando a relação C/N igual a 60 : 1, realizaram-se dois experimentos para avaliar a degradação de cavacos de Eucalyptus saligna por isolados fúngicos de podridão-branca. No primeiro experimento, avaliado aos 90 dias de incubação, foram selecionados sete isolados, que causaram perda de peso em cavacos superior ou igual à causada por Trametes versicolor, usado para comparação. No segundo experimento foram testados 46 isolados fúngicos. Dentre os mais eficientes estavam os sete isolados selecionados no primeiro teste, além de outros quatro isolados. Baseado na análise de DNA, seis isolados foram identificados, sendo três pertencentes à espécie Pycnoporus sanguineus, um ao gênero Peniophora sp., um ao gênero Pestalotiopsis sp. e um ao gênero Ganoderma sp.The aim of this work was to isolate native wood white-rot fungi from fungal fruit-bodies and eucalyptus wood fragments from different regions of Brazil and to test their potential for degrading dead stumps and roots in Eucalyptus plantings after harvest. Fungi isolates were obtained in a culture medium composed by Eucalyptus sawdust and agar. Among 292 isolates submitted to the Banvedamm test, 144 were classified as phenoloxidases producing isolates. Among nine C

  7. INFLUÊNCIA DA DENSIDADE DE INÓCULO DE Fusarium solani f.sp. phaseoli NA SEVERIDADE DA PODRIDÃO RADICULAR SECA DO FEIJOEIRO EFFECT OF Fusarium solani f.sp. phaseoli INOCULUM DENSITY ON DRY ROOT ROT SEVERITY IN THE COMMON BEAN

    Directory of Open Access Journals (Sweden)

    Gesimária Ribeiro Costa

    2007-09-01

    Full Text Available

    Foram testadas quatro densidades de inóculo de Fusarium solani, em gramas por litro de solo (1,0; 2,0; 4,0 e 8,0 e um tratamento testemunha, em solo tipo Latossolo Vermelho-Escuro, cultivado e não cultivado, com o objetivo de determinar a densidade mínima de inóculo no solo necessária para a ocorrência de podridão radicular seca do feijoeiro. Como variáveis respostas foram avaliadas: número de microorganismos totais do solo, número de propágulos de F. solani, atividade microbiológica total do solo e severidade da doença em plântulas. Os resultados indicaram que a densidade de inóculo do fungo variou com o tipo de solo. Para um solo não cultivado a densidade necessária para causar a doença esteve acima de 5.127 propágulos por grama de solo, enquanto para o solo cultivado a densidade de inóculo para causar doença foi de 3.701 propágulos por grama de solo. Os índices de doença em plântulas cultivadas sob o solo cultivado foram duas vezes superiores ao índice de doença de plântulas sob o solo não cultivado. A atividade microbiológica total nos solos, determinada pela desidrogenase de fluorescina diacetato, não se correlacionou com a população dos microorganismos, indicando que a simples presença desses não implica em que estejam ativos.

    PALAVRAS-CHAVE: Solo supressivo; solo conducivo; Phaseolus vulgaris.

    Four densities of Fusarium solani inoculum (1, 2, 4 and 8 g/L of soil were tested for determining the minimum inoculum density for the occurrence of bean dry root rot, in two soil types. The response variables evaluated were the total number of microorganisms in the soil, the number of F. solani f. sp. phaseoli propagules, total soil microbial activity and seedling disease severity

  8. 7 CFR 51.1563 - Soft rot or wet breakdown.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Soft rot or wet breakdown. 51.1563 Section 51.1563... STANDARDS) United States Standards for Grades of Potatoes 1 Definitions § 51.1563 Soft rot or wet breakdown. Soft rot or wet breakdown means any soft, mushy, or leaky condition of the tissue such as slimy...

  9. 7 CFR 51.1582 - Soft rot or wet breakdown.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Soft rot or wet breakdown. 51.1582 Section 51.1582... STANDARDS) United States Consumer Standards for Potatoes Definitions § 51.1582 Soft rot or wet breakdown. Soft rot or wet breakdown means any soft, mushy, or leaky condition of the tissue such as slimy...

  10. QTL mapping of fruit rot resistance to the plant pathogen Phytophthora capsici in a recombinant inbred line Capsicum annuum population.

    Science.gov (United States)

    Naegele, R P; Ashrafi, H; Hill, T A; Chin-Wo, S Reyes; Van Deynze, A E; Hausbeck, M K

    2014-05-01

    Phytophthora capsici is an important pepper (Capsicum annuum) pathogen causing fruit and root rot, and foliar blight in field and greenhouse production. Previously, an F6 recombinant inbred line population was evaluated for fruit rot susceptibility. Continuous variation among lines and partial and isolate-specific resistance were found. In this study, Phytophthora fruit rot resistance was mapped in the same F6 population between Criollo del Morelos 334 (CM334), a landrace from Mexico, and 'Early Jalapeno' using a high-density genetic map. Isolate-specific resistance was mapped independently in 63 of the lines evaluated and the two parents. Heritability of the resistance for each isolate at 3 and 5 days postinoculation (dpi) was high (h(2) = 0.63 to 0.68 and 0.74 to 0.83, respectively). Significant additive and epistatic quantitative trait loci (QTL) were identified for resistance to isolates OP97 and 13709 (3 and 5 dpi) and 12889 (3 dpi only). Mapping of fruit traits showed potential linkage with few disease resistance QTL. The partial fruit rot resistance from CM334 suggests that this may not be an ideal source for fruit rot resistance in pepper. PMID:24168044

  11. Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white rot/brown rot paradigm for wood decay fungi

    Science.gov (United States)

    Basidiomycota (basidiomycetes) make up 32% of the described fungi and include most wood decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade ...

  12. Molecular Characterization of Resistant Accessions of Cocoa (Theobroma cocoa L.) to Phytophthora Pod Rot Selected on-Farm in Côte-d’Ivoire.

    Science.gov (United States)

    Cocoa is (Theobroma cacao L.) is a significant agricultural commodity in Côted’Ivoire which ranks 1st in the world cocoa export. Phytophthora pod rot (Ppr)also call Black pod is the most widespread disease of cocoa. Lost due to this disease depends on the species of the pathogen and vary globally fr...

  13. Myxomycetes of the rotting cherry wood

    Directory of Open Access Journals (Sweden)

    Wanda Stojanowska

    2014-08-01

    Full Text Available During the years 1974-1975 on rotting cherry wood development of some Myxomycetes was observed. In that time 6 species of slime molds were noted: Arcyria denudata, Comatricha typhoides, Dyctidium cancellatum, Lycogala epidendrum, Physarum cinereum, Stemonitis ferruginea. In the decomposition of organic compounds apart from Myxomycetes other organism (Coprinus dessiminafus also take part.

  14. Everbearing strawberry cultivars - susceptibility to crown rot

    OpenAIRE

    Parikka, Päivi; Karhu, Saila; Hietaranta, Tarja

    2009-01-01

    Studies on the production of everbearing strawberry cultivars were started at MTT Plant Production Research in 2007. MTT Horticulture makes trials in tunnel and open fields to study the growth, yield and overwintering of cultivars in northern conditions. Resistance to crown rot is also being tested.

  15. 赞皇枣黑腐病菌拮抗链霉菌的室内多重筛选及发酵条件优化%Screening in vitro of Antagonistic Streptomyces against the Black Rot Disease (Alternaria tenuissima) of Zanhuang Jujube Fruit and Optimization of Fermentation Conditions

    Institute of Scientific and Technical Information of China (English)

    高芬; 李静虹; 王俊宏; 王梦亮

    2015-01-01

    【目的】本研究旨在获得对赞皇枣黑腐病菌具有良好抑制作用的拮抗链霉菌,并对其发酵培养基配方和条件进行优化,以期为进行田间试验和开发生防制剂奠定基础。【方法】以赞皇枣黑腐病优势病原真菌———细极链格孢菌为靶标,采用琼脂块法、牛津杯法和含药平板法对从特殊生境分离获得的10株抗真菌链霉菌进行室内多重筛选,并采用二次回归正交旋转设计和单因素试验对筛选获得的拮抗链霉菌分别进行发酵培养基优化和最佳发酵条件确立。【结果】活体筛选试验中,菌株 AC03、AC04和 AC07表现出了明显的拮抗效果,抑菌圈直径分别为(32.09±1.45),(15.75±1.34),(18.33±0.78)mm;上述3株菌的无菌发酵滤液活性测定表明:菌株AC03、AC07的抑菌圈直径分别为(20.94±0.92)和(23.44±1.63) mm,而菌株 AC04仅为(14.5±0.71) mm;对菌株 AC03和AC07进行无菌发酵滤液的菌丝生长抑制试验,结果表明:菌株 AC07代谢产生的拮抗物质抑菌效果、持效性均优于 AC03。综上可知,菌株 AC07对赞皇枣黑腐病菌的抑菌效果最优。AC07的最优发酵培养基配方为:麦芽糖5.7%,大豆粉2.7%,( NH4)2 SO40.17%,CaCO30.22%,NaCl 0.17%,酵母粉0.2%;最佳发酵条件为:种子液浓度1.5×107~2×108 cfu·mL -1时,接种量2%(V/V),装液量40 mL/250 mL三角瓶,原始pH7.0,发酵温度28℃,发酵时间108 h。【结论】筛选获得的目标拮抗菌 AC07可为开发针对赞皇枣黑腐病的生物农药提供新的原材料,且发酵培养基和条件的优化,提高了目标代谢物的产量,为后续的研究和开发奠定基础。%[Objective]The Zanhuang jujube ( Ziziphus jujuba‘Zanhuang’) fruit black rot disease is one of the most serious fungal pathogens in China. Bio-control of the disease is of great significance to the fruit green production and its sustained efficacy as well as

  16. Postharvest respiration rate and sucrose content of Rhizoctonia-infected sugarbeet roots

    Science.gov (United States)

    Rhizotonia crown and root rot of sugarbeet, caused by Rhizoctonia solani AG 2-2, is increasing in Minnesota and North Dakota. As the disease increases in prevalence and severity, more diseased roots are being stored in piles where they affect storability and postharvest quality. The objective of th...

  17. Roots Revisited.

    Science.gov (United States)

    Hughes, Barnabas

    1998-01-01

    Offers historical information about square roots. Presents three different methods--Hero's method, visual method, and remainder method--which can be used to teach the finding of square roots and one method for determining cube roots. (ASK)

  18. Isolation of laccase gene-specific sequences from white rot and brown rot fungi by PCR

    Energy Technology Data Exchange (ETDEWEB)

    D`Souza, T.M.; Boominathan, K.; Reddy, C.A. [Michigan State Univ., East Lansing, MI (United States)

    1996-10-01

    Degenerate primers corresponding to the consensus sequences of the copper-binding regions in the N-terminal domains of known basidiomycete laccases were used to isolate laccase gene-specific sequences from strains representing nine genera of wood rot fungi. All except three gave the expected PCR product of about 200 bp. Computer searches of the databases identified the sequences of each of the PCR product of about 200 bp. Computer searches of the databases identified the sequence of each of the PCR products analyzed as a laccase gene sequence, suggesting the specificity of the primers. PCR products of the white rot fungi Ganoderma lucidum, Phlebia brevispora, and Trametes versicolor showed 65 to 74% nucleotide sequence similarity to each other; the similarity in deduced amino acid sequences was 83 to 91%. The PCR products of Lentinula edodes and Lentinus tigrinus, on the other hand, showed relatively low nucleotide and amino acid similarities (58 to 64 and 62 to 81%, respectively); however, these similarities were still much higher than when compared with the corresponding regions in the laccases of the ascomycete fungi Aspergillus nidulans and Neurospora crassa. A few of the white rot fungi, as well as Gloeophyllum trabeum, a brown rot fungus, gave a 144-bp PCR fragment which had a nucleotide sequence similarity of 60 to 71%. Demonstration of laccase activity in G. trabeum and several other brown rot fungi was of particular interest because these organisms were not previously shown to produce laccases. 36 refs., 6 figs., 2 tabs.

  19. Sheath rot of rice in Iran.

    Science.gov (United States)

    Naeimi, S; Okhovvat, S M; Hedjaroude, G A; Khosravi, V

    2003-01-01

    Sheath rot of rice occurs in most rice-growing regions of the world. It usually causes yield losses from 20 to 85%. Sheath rot was reported from Iran in 1993. Year after year, the number of diseased plants increased in the Northern Iran. In summer of 2001, these symptoms were observed in most fields: lesions occur on the upper leaf sheaths, especially the flag leaf sheath. As the disease progresses, lesions enlarge and coalesce and may cover most of the leaf sheath. Panicle may fail to completely or at all. Brown or partially brown not filled or partially filled grain is also associated with infection of the panicle. A whitish powdery growth may be found inside affected sheaths. Infected plants were collected and trasferred to laboratory. Small pieces of diseased tissues were washed under tap water for one hour. Then tissues were placed on WA and incubated at 25 degrees C. These isolates were purified and identified as: Sarocladium oryzae, Fusarium udum, F. semitectum, F. avenaceum, F. flocciferum, F. graminearum, Bipolaris oryzae, Alternaria padwickii, Rhizoctonia solani, Paecilomyces sp., Nigrospora sp. and Trichoderma sp. This is the first report of F. udum in Iran. Also this is the first report that rice is the host for F. semitectum, F. avenaceum and F. flocciferum in Iran. Pathogenicity tests were conducted in glass house. Following species were found to be associated with sheath rot of rice: S. oryzae, F. graminearum, F. udum, F. avenaceum, B. oryzae, A. padwickii. This is the first report in the world that F. udum and A. padwickii are the causal agents of the sheath rot on rice plants. PMID:15151303

  20. Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi.

    Science.gov (United States)

    Riley, Robert; Salamov, Asaf A; Brown, Daren W; Nagy, Laszlo G; Floudas, Dimitrios; Held, Benjamin W; Levasseur, Anthony; Lombard, Vincent; Morin, Emmanuelle; Otillar, Robert; Lindquist, Erika A; Sun, Hui; LaButti, Kurt M; Schmutz, Jeremy; Jabbour, Dina; Luo, Hong; Baker, Scott E; Pisabarro, Antonio G; Walton, Jonathan D; Blanchette, Robert A; Henrissat, Bernard; Martin, Francis; Cullen, Dan; Hibbett, David S; Grigoriev, Igor V

    2014-07-01

    Basidiomycota (basidiomycetes) make up 32% of the described fungi and include most wood-decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade lignin along with cellulose and hemicellulose. Prior genomic comparisons suggested that the two decay modes can be distinguished based on the presence or absence of ligninolytic class II peroxidases (PODs), as well as the abundance of enzymes acting directly on crystalline cellulose (reduced in brown rot). To assess the generality of the white-rot/brown-rot classification paradigm, we compared the genomes of 33 basidiomycetes, including four newly sequenced wood decayers, and performed phylogenetically informed principal-components analysis (PCA) of a broad range of gene families encoding plant biomass-degrading enzymes. The newly sequenced Botryobasidium botryosum and Jaapia argillacea genomes lack PODs but possess diverse enzymes acting on crystalline cellulose, and they group close to the model white-rot species Phanerochaete chrysosporium in the PCA. Furthermore, laboratory assays showed that both B. botryosum and J. argillacea can degrade all polymeric components of woody plant cell walls, a characteristic of white rot. We also found expansions in reducing polyketide synthase genes specific to the brown-rot fungi. Our results suggest a continuum rather than a dichotomy between the white-rot and brown-rot modes of wood decay. A more nuanced categorization of rot types is needed, based on an improved understanding of the genomics and biochemistry of wood decay. PMID:24958869

  1. Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white rot/ brown rot paradigm for wood decay fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Brown, Daren W.; Nagy, Laszlo G.; Floudas, Dimitris; Held, Benjamin; Levasseur, Anthony; Lombard, Vincent; Morin, Emmanuelle; Otillar, Robert; Lindquist, Erika; Sun, Hui; LaButti, Kurt; Schmutz, Jeremy; Jabbour, Dina; Luo, Hong; Baker, Scott E.; Pisabarro, Antonio; Walton, Jonathan D.; Blanchette, Robert; Henrissat, Bernard; Martin, Francis; Cullen, Dan; Hibbett, David; Grigoriev, Igor V.

    2014-03-14

    Basidiomycota (basidiomycetes) make up 32percent of the described fungi and include most wood decaying species, as well as pathogens and mutualistic symbionts. Wood-decaying basidiomycetes have typically been classified as either white rot or brown rot, based on the ability (in white rot only) to degrade lignin along with cellulose and hemicellulose. Prior genomic comparisons suggested that the two decay modes can be distinguished based on the presence or absence of ligninolytic class II peroxidases (PODs), as well as the abundance of enzymes acting directly on crystalline cellulose (reduced in brown rot). To assess the generality of the white rot/brown rot classification paradigm we compared the genomes of 33 basidiomycetes, including four newly sequenced wood decayers, and performed phylogenetically-informed Principal Components Analysis (PCA) of a broad range of gene families encoding plant biomass-degrading enzymes. The newly sequenced Botryobasidium botryosum and Jaapia argillacea genomes lack PODs, but possess diverse enzymes acting on crystalline cellulose, and they group close to the model white rot species Phanerochaete chrysosporium in the PCA. Furthermore, laboratory assays showed that both B. botryosum and J. argillacea can degrade all polymeric components of woody plant cell walls, a characteristic of white rot. We also found expansions in reducing polyketide synthase genes specific to the brown rot fungi. Our results suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. A more nuanced categorization of rot types is needed, based on an improved understanding of the genomics and biochemistry of wood decay.

  2. Thermal control of some post-harvest rot pathogens of Irish potato (solanum tuberosum l.

    Directory of Open Access Journals (Sweden)

    Salami Olusola Abiodun

    2007-01-01

    Full Text Available Thermal control effect on the incidence of some post-harvest rot pathogens of Solanum tuberosum (potato was investigated in this study. Three cultivars of potato tuber whose local names are, Patiska, Mai Bawondoya and Nicola were used for the study. Five pathogenic fungi viz: Botryodiplodia theobromae, Fusarium redolens, Fusarium oxysporum, Penicillium sp. and Rhizopus oryzae associated with post harvest storage rot of root-tubers, were isolated from diseased potatoes. Among the three species of potatoes used in the study, Patiska was found most resistant followed by Mai Bawondoya, while Nicola was the least resistant. Increase in substrate (i.e. soluble starch or CMC concentration enhanced a proportional increase in mycelial growth and in the amount of extracellular enzymes produced. Some of these test pathogens were found to produce cell wall degrading enzymes (i.e. amylase and cellulase. Preferential utilization of carbohydrate sources was established in this study based on the growth of test pathogens. Growth on potato broth medium was highest followed by growth on Cocoyam and Sweet potato broth media and least on Cassava broth medium. Growth of the test pathogens on carbohydrate sources was found at variant. The use of hot water treatment at different temperatures was found to significantly reduce post-harvest fungal populations on the surface of root-tubers. The efficacy of blanching in hot water at 60˚C was significantly higher than that of blanching in hot water at other temperatures. The control method adopted in this study showed that the problems of potatoes’ rot disease in storage (especially by the peasant farmers can be eradicated by thermal treatments without reducing the quality of the Irish tuber.

  3. Identification of Rhizoctonia solani isolates from sugar beet roots by analyzing the ITS region of ribosomal DNA

    OpenAIRE

    Stojšin Vera B.; Budakov Dragana; Jacobsen Barry; Grimme Eva; Bagi Ferenc F.; Jasnić Stevan

    2007-01-01

    Rhizoctonia solani (Kühn) is one of the most important sugar beet pathogens Rhizoctonia solani anastomosis groups (AGs) 2-2 and 4 are proven to be the most common pathogenic strains on sugar beet. AG 2-2 (intraspecific groups IIIB and IV) can cause root and crown rot while damping-off of seedlings is most frequently attributed to AG 4. Four isolates of R. solani from sugar beet roots showing characteristic crown and root rot symptoms, collected from different localities in Vojvodina Province,...

  4. Tolerance to Phytophthora Fruit Rot in Watermelon Plant Introductions

    Science.gov (United States)

    Phytophthora capsici is distributed worldwide, and is an aggressive pathogen with a broad host range infecting solanaceous, leguminaceous, and cucurbitaceous crops. Fruit rot, caused by P. capsici is an emerging disease in most watermelon producing regions of Southeast US. Resistance to fruit rot o...

  5. Distribuição do sistema radicular de árvores de acáia-negra oriundas de mudas produzidas em diferentes recipientes Influence of seedling production method on the root system distribution of black wattle trees

    Directory of Open Access Journals (Sweden)

    Aline Fagote Paulino

    2003-10-01

    Full Text Available O objetivo deste trabalho foi estudar a distribuição do sistema radicular de árvores de acácia-negra (Acacia mearnsii com 3 anos de idade, provenientes de mudas formadas em diferentes recipientes e instaladas em um Argissolo no Rio Grande do Sul. Os recipientes utilizados foram: laminado, tubete redondo e bandeja de isopor. As avaliações da distribuição das raízes foram feitas pelo método da parede do perfil até 1 m de profundidade, na linha e na entrelinha de plantio. Foram feitas, também, análises físicas do solo: densidade, porosidade total e distribuição de poros. O recipiente usado na formação da muda influenciou o crescimento do sistema radicular da planta no campo. O laminado de madeira apresentou-se superior ao tubete quanto ao comprimento de raízes nas linhas de plantio. As raízes cresceram melhor nas linhas de plantio, onde as condições de densidade e porosidade do solo se encontravam mais adequadas.The purpose of this study was to evaluate the root system distribution of three-year-old black wattle (Acacia mearnsii trees. The plants were originated from seedlings grown in different containers and planted in an Argisol in the state of Rio Grande do Sul, Brazil. The containers used for seedling production were: wood laminated pots, round plastic tubettes and styrofoam trays. The evaluations were carried out using the trench profile method up to 1 m depth on tree rows and inter-rows. The following soil analyses were also carried out: bulk density, total porosity and pore distribution. The type of container used influenced the development of the root system of trees on the field. Wood laminated pots were better than the round tubettes for root length in the tree rows. The roots developed better on the tree rows where soil density and porosity conditions were more adequate.

  6. Allelopathic effect of black mustard tissues and root exudates on some crops and weeds Efeito alelopático de tecidos de mostarda-preta e exsudatos da raiz de algumas culturas e plantas daninhas

    Directory of Open Access Journals (Sweden)

    E Al-Sherif

    2013-03-01

    Full Text Available Laboratory and greenhouse experiments were conducted to evaluate the phytotoxic effect of black mustard extracts and root exudates on two crops: Trifolium alexandrinum and Triticum aestivum, and two weeds: Phalaris paradoxa and Sisymbrium irio. The seeds were treated with aqueous and ethanolic extracts and chloroform for eight days, or subjected to root exudates of just harvested mustard in a greenhouse for five weeks. High-performance liquid chromatography (HPLC was used to quantify phytotoxins from plant tissues. Seed germination of P. paradoxa was reduced with the lowest concentration of the different extracts. However, the aqueous extract at 4% completely curtailed the germination of all the target species. In general, plant extracts had a concentration-dependent reduction of seedling growth of the target species. However, the ethanolic extract, at the lowest concentration, has stimulated the shoot length of both T. alexandrinum and T. aestivum, and the root length of the former. Mustard root exudates inhibited emergence and growth of the target species throughout the experiment. Ferulic and syringic acids were the dominant allelochemicals found when HPLC was used.Experimentos de laboratório e estufa foram realizados para avaliar o efeito fitotóxico dos extratos de mostarda-preta e exsudatos de raiz de duas culturas: Trifolium alexandrinum e Triticum aestivum, bem como de duas plantas daninhas: Phalaris paradoxa e Sisymbrium irio. As sementes foram tratadas com extratos aquosos, etanólicos e clorofórmio por oito dias, ou submetidas a exsudatos de raiz de mostarda recém-colhidaem estufa durante cinco semanas. A cromatografia líquida de alto desempenho (HPLC foi usada para a quantificação de fitotoxinas a partir de tecidos de plantas. Sementes de P. paradoxa apresentam germinação reduzida com a menor concentração dos diferentes extratos. No entanto, o extrato aquoso a 4% restringiu completamente a germinação de todas as esp

  7. Identification and mycotoxigenic capacity of fungi associated with pre- and postharvest fruit rots of pomegranates in Greece and Cyprus.

    Science.gov (United States)

    Kanetis, Loukas; Testempasis, Stefanos; Goulas, Vlasios; Samuel, Stylianos; Myresiotis, Charalampos; Karaoglanidis, George S

    2015-09-01

    Pre- and postharvest fruit rots of fungal origin are an important burden for the pomegranate industry worldwide, affecting the produce both quantitatively and qualitatively. During 2013, local orchards were surveyed and 280 fungal isolates from Greece (GR) and Cyprus (CY) were collected from pomegranates exhibiting preharvest rot symptoms, and additional 153 isolates were collected postharvest from cold-stored fruit in GR. Molecular identification revealed that preharvest pomegranate fruit rots were caused predominately by species of the genera Aspergillus (Aspergillus niger and Aspergillus tubingensis) and Alternaria (Alternaria alternata, Alternaria tenuissima, and Alternaria arborescens). By contrast, postharvest fruit rots were caused mainly by Botrytis spp. and to a lesser extent by isolates of Pilidiella granati and Alternaria spp. Considering that a significant quota of the fungal species found in association with pomegranate fruit rots are known for their mycotoxigenic capacity in other crop systems, their mycotoxin potential was examined. Alternariol (AOH), alternariol monomethyl-ether (AME) and tentoxin (TEN) production was estimated among Alternaria isolates, whereas ochratoxin A (OTA) and fumonisin B2 (FB2) production was assessed within the black aspergilli identified. Overall in both countries, 89% of the Alternaria isolates produced AOH and AME in vitro, while TEN was produced only by 43.9%. In vivo production of AOH and AME was restricted to 54.2% and 31.6% of the GR and CY isolates, respectively, while none of the isolates produced TEN in vivo. Among black aspergilli 21.7% of the GR and 17.8% of the CY isolates produced OTA in vitro, while in vivo OTA was detected in 8.8% of the isolates from both countries. FB2 was present in vitro in 42.0% of the GR and 22.2% of the CY isolates, while in vivo the production was limited to 27.5% and 4.5% of the GR and the CY isolates, respectively. Our data imply that mycotoxigenic Alternaria and Aspergillus

  8. GammaScorpion: mobile gamma-ray tomography system for early detection of basal stem rot in oil palm plantations

    Science.gov (United States)

    Abdullah, Jaafar; Hassan, Hearie; Shari, Mohamad Rabaie; Mohd, Salzali; Mustapha, Mahadi; Mahmood, Airwan Affendi; Jamaludin, Shahrizan; Ngah, Mohd Rosdi; Hamid, Noor Hisham

    2013-03-01

    Detection of the oil palm stem rot disease Ganoderma is a major issue in estate management and production in Malaysia. Conventional diagnostic techniques are difficult and time consuming when using visual inspection, and destructive and expensive when based on the chemical analysis of root or stem tissue. As an alternative, a transportable gamma-ray computed tomography system for the early detection of basal stem rot (BSR) of oil palms due to Ganoderma was developed locally at the Malaysian Nuclear Agency, Kajang, Malaysia. This system produces high quality tomographic images that clearly differentiate between healthy and Ganoderma infected oil palm stems. It has been successfully tested and used to detect the extent of BSR damage in oil palm plantations in Malaysia without the need to cut down the trees. This method offers promise for in situ inspection of oil palm stem diseases compared to the more conventional methods.

  9. Root fractures

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Christensen, Søren Steno Ahrensburg; Tsilingaridis, Georgios

    2012-01-01

    The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed.......The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed....

  10. Square Root +

    Science.gov (United States)

    Frederiksen, John G.

    1969-01-01

    A rational presentation of the so-called long division method for extracting the square root of a number. Diagrams are used to show relationship of this technique to the binomial theorem. Presentation exposes student to many facets of mathematics in addition to the mechanics of funding square root and cube root. Geometry, algebraic statements,…

  11. Co-inoculation with rhizobia and AMF inhibited soybean red crown rot: from field study to plant defense-related gene expression analysis.

    Directory of Open Access Journals (Sweden)

    Xiang Gao

    Full Text Available BACKGROUND: Soybean red crown rot is a major soil-borne disease all over the world, which severely affects soybean production. Efficient and sustainable methods are strongly desired to control the soil-borne diseases. PRINCIPAL FINDINGS: We firstly investigated the disease incidence and index of soybean red crown rot under different phosphorus (P additions in field and found that the natural inoculation of rhizobia and arbuscular mycorrhizal fungi (AMF could affect soybean red crown rot, particularly without P addition. Further studies in sand culture experiments showed that inoculation with rhizobia or AMF significantly decreased severity and incidence of soybean red crown rot, especially for co-inoculation with rhizobia and AMF at low P. The root colony forming unit (CFU decreased over 50% when inoculated by rhizobia and/or AMF at low P. However, P addition only enhanced CFU when inoculated with AMF. Furthermore, root exudates of soybean inoculated with rhizobia and/or AMF significantly inhibited pathogen growth and reproduction. Quantitative RT-PCR results indicated that the transcripts of the most tested pathogen defense-related (PR genes in roots were significantly increased by rhizobium and/or AMF inoculation. Among them, PR2, PR3, PR4 and PR10 reached the highest level with co-inoculation of rhizobium and AMF. CONCLUSIONS: Our results indicated that inoculation with rhizobia and AMF could directly inhibit pathogen growth and reproduction, and activate the plant overall defense system through increasing PR gene expressions. Combined with optimal P fertilization, inoculation with rhizobia and AMF could be considered as an efficient method to control soybean red crown rot in acid soils.

  12. Black to Black

    DEFF Research Database (Denmark)

    Langkjær, Michael Alexander

    2012-01-01

    Pop musicians performing in black stage costume take advantage of cultural traditions relating to matters black. Stylistically, black is a paradoxical color: although a symbol of melancholy, pessimism, and renunciation, black also expresses minimalist modernity and signifies exclusivity (as...... is hinted by Rudyard Kipling’s illustration of ‘The [Black] Cat That Walked by Himself’ in his classic children’s tale). It was well understood by uniformed Anarchists, Fascists and the SS that there is an assertive presence connected with the black-clad figure. The paradox of black’s abstract elegance......-styled references to, among other things, the culturally and ideologically effervescent interwar-period have made me curious as to what alternative possibilities – for instance ‘emancipation’ – a comparative analysis might disclose concerning the visual rhetoric of black. Thus, in conclusion, it is briefly...

  13. La Nation et ses mémoires The Nation and its Memories. Indian and Black Narratives on Roots and Belonging (Mexico, Columbia

    Directory of Open Access Journals (Sweden)

    Anath Ariel de Vidas

    2011-04-01

    Full Text Available Les grands récits des constructions nationales latino-américaines opposent généralement l’ancestralité des Indiens à l’arrivée postérieure des esclaves noirs. L’analyse des régimes mémoriels de groupes indiens et afrodescendants contemporains, au Mexique et en Colombie, démontre que leur mémoire collective ne s’organise pas forcément en fonction de cette opposition binaire, mais qu’elle s’agence plutôt selon les modalités d’insertion territoriale et d’appartenance régionales. Cet article nuance et réfute donc la pierre de touche que représente cette catégorie classificatrice d’autochtonie et propose une vision contextualisée des dispositifs mémoriels, dans le temps et l’espace social. Ces dispositifs articulent des dimensions culturelles et politiques pour forger des configurations identitaires originales et non déterminées par l’origine ethnique ou raciale des groupes concernés.The main narratives of Latin-American national constructions generally oppose the ancestrality of the Indians to the later arrival of black slaves. This analysis of the memorial systems of Indian groups and contemporary afro-descendants, in Mexico and in Colombia, shows that their collective memory does not organize itself necessarily according to this binary opposition but rather according to specific modalities of territorial integration and of regional belonging. This article qualifies and refutes the validity of this classifying category of autochthony and proposes a contextualized vision of the memorial mechanisms in social time and space. These mechanisms articulate cultural and political dimensions to forge original identitarian configurations not determined by the ethnic or racial origin of the concerned groups.

  14. Roots & Hollers

    OpenAIRE

    Kollman, Patrick L; Gorman, Thomas A.

    2011-01-01

    Roots & Hollers, 2011 A documentary by Thomas Gorman & Patrick Kollman Master’s Project Abstract: Roots & Hollers uncovers the wild American ginseng trade, revealing a unique intersection between Asia and rural America. Legendary in Asia for its healing powers, ginseng helps sustain the livelihoods of thousands in Appalachia. A single root can sell for thousands of dollars at auction. Shot on-location in the mountains of Kentucky and West Virginia, this student doc...

  15. Aplicação superficial de diferentes fontes de corretivos no crescimento radicular e produtividade da aveia preta Surface application by different lime source in root growth and yield of black oat

    Directory of Open Access Journals (Sweden)

    Juliano Corulli Corrêa

    2008-08-01

    Full Text Available Em solos ácidos, a prática da calagem superficial favorece o crescimento radicular, principalmente na superfície do solo, bem como a produtividade das culturas em condições normais de precipitação pluviométrica. Entretanto, pouco se sabe sobre a adoção desta prática e suas eventuais ações, no solo e nas plantas, em relação a outras fontes de corretivos. O objetivo do trabalho foi avaliar o efeito da aplicação superficial de diferentes corretivos nos atributos químicos do solo, no crescimento radicular, da parte aérea e na produtividade da aveia preta. O trabalho foi desenvolvido em campo sobre Latossolo Vermelho distrófico, durante o ano agrícola de 2004, dois anos após a aplicação superficial dos corretivos, no sistema plantio direto. Os tratamentos constituíram da aplicação superficial de calcário dolomítico, escoria de aciaria - E, lama cal - Lcal, lodo de esgoto centrifugado - LC e sem aplicação de corretivo, em delineamento em blocos casualizados com quatro repetições. A aplicação superficial de calcário, escória de aciaria, lama cal, lodo de esgoto centrifugado permitiu o aumento nos valores de pH, no teor de Ca, na maior disponibilidade de P e na redução dos teores de Al no solo. O crescimento do sistema radicular, o desenvolvimento da parte aérea e a produtividade da aveia preta foram incrementados com a aplicação superficial dos corretivos de acidez no sistema plantio direto.Surface lime application to an acid soil under no-till system and normal rainfall conditions increases yield and crop root growth near the soil surface, but the effects of lime sources like flue dust, sewage sludge and aqueous lime have not been fully investigated . The experiment aimed to evaluate the effects of surface application of different lime sources on soil chemical attributes of a clayey, dystrophic Oxisol and black oat root growth and yield under a no-till system. Evaluations were conducted two years after the

  16. Evaluation of natural plant extracts, antagonists and fungicides in controlling root rot, collar rot, fruit (brown rot and gummosis of citrus caused by Phytophthora spp. in vitro

    Directory of Open Access Journals (Sweden)

    G.P. Jagtap

    2012-07-01

    Full Text Available The results revealed that all the six bioagents tested in vitro applying dual culture technique against Phytophthora nicotianae, Phytophthora citrophthora and Phytophthora palmivora significantly inhibited the mycelial growth of the test pathogen over untreated control. However, bioagent, Trichoderma harzianum recorded minimum mean colony diameter (7.73 cm2 and highest inhibition (87.85% of mycelial growth of P. nicotianae over untreated control followed by the bioagent T. viride, T. koningii which recorded mean colony diameter of 9.95 cm2, 14.15 cm2 and mean mycelial inhibition of 84.36 %, 77.76%, respectively. Evaluation of different botanicals by Poisoned Food Technique showed that all plant extracts tested in vitro were found significantly effective in reducing the percentage mycelial growth of P. nicotianae, P. citrophthora and P. palmivora over untreated control. However, plant extract (@ 5, 10 and 15% of Garlic, recorded lowest mean colony diameter (47.45 mm and highest mean mycelial growth inhibition (47.26% followed by Neem, Onion which recorded the mycelial growth of 55.20 mm, 60.85 mm, and the mean mycelial growth inhibition of 38.65%, 32.38%, respectively. Results revealed that all the nine fungicides tested in vitro applying Poisoned Food Technique against P. nicotianae, P. citrophthora and P. palmivora significantly inhibited the mycelial growth of the test pathogen over untreated control. However, fungicide, Cymoxynil 8% + Mancozeb 64% (Curzate M-8 recorded minimum mean colony diameter (16.12 mm and maximum mean inhibition (82.09% of mycelial growth of the test pathogen over untreated control (mean colony diameter 90.00 mm and mean inhibition 0.00 followed by the fungicide Metalaxyl-M 4% + Mancozeb 64% (Ridomil Gold, Metyram (Polyram, which recorded mean colony diameter of 20.16 mm, 24.16 mm and mean mycelial inhibition of 77.59%, 73.14%, respectively.

  17. Root doctors as providers of primary care.

    Science.gov (United States)

    Stitt, V J

    1983-07-01

    Physicians in primary care recognize that as many as 65 percent of the patients seen in their offices are there for psychological reasons. In any southern town with a moderate population of blacks, there are at least two "root doctors." These root doctors have mastered the power of autosuggestion and are treating these patients with various forms of medication and psychological counseling. This paper updates the practicing physician on root doctors who practice primary care. PMID:6887277

  18. Production of Ligninolytic Enzymes by White-Rot Fungus Datronia sp. KAPI0039 and Their Application for Reactive Dye Removal

    OpenAIRE

    Pilanee Vaithanomsat; Waraporn Apiwatanapiwat; Oncheera Petchoy; Jirawate Chedchant

    2010-01-01

    This study focused on decolorization of 2 reactive dyes; Reactive Blue 19 (RBBR) and Reactive Black 5 (RB5), by selected white-rot fungus Datronia sp. KAPI0039. The effects of reactive dye concentration, fungal inoculum size as well as pH were studied. Samples were periodically collected for the measurement of color unit, Laccase (Lac), Manganese Peroxidase (MnP), and Lignin Peroxidase (LiP) activity. Eighty-six percent of 1,000 mg L−1 RBBR decolorization was achieved by 2% (w/v) Datronia sp....

  19. Erwinia carotovora extracellular proteases : characterization and role in soft rot

    OpenAIRE

    Kyöstiö, Sirkka R. M.

    1990-01-01

    Erwinia carotovora subsp. carotovora (Ecc) strain EC14, a Gram-negative bacterium, causes soft rot on several crops, including potato. Maceration of potato tuber tissue is caused by secreted pectolytic enzymes. Other cell-degrading enzymes may also have roles in pathogenesis, including cellulases, phospholipases, and protease(s). The objectives of this research were to (1) characterize Ecc extracellular protease (Prt) and (2) elucidate its role in potato soft rot. A gene enc...

  20. Occurrence of Sclerotium Rot of Cucumber Caused by Sclerotium rolfsii

    OpenAIRE

    Jin-Hyeuk Kwon; Sang-Dae Lee; Okryun Choi; Shun-Shan Shen; Hong-Sik Shim

    2015-01-01

    Sclerotium rot of cucumber (Cucumis sativus L.) occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in July 2012. The typical symptoms included wilt, rot, and water-soaking on stems and fruits and severely infected plants eventually died. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, white to brown in color and 1−3 mm in size and the hyphal wi...

  1. Studies Of Enoinia Soft Rot Disease On Potato

    OpenAIRE

    Safni, Irda

    2008-01-01

    E. caroiooora subsp. caroiouora (Ecc), the soft rot bacteria of potato, survives for a long period in lenticels and suberized wounds during storage. The disease is more severe when the environmental conditions favour its development, therefore, managing soft rot disease is a difficult task. Washed and brushed potato tubers, which were artificially inoculated using different inoculation methods, were used in this study to detect the population of Ecc in tuber. The number of Ecc were assessed b...

  2. Identification and Pathogenicity of Phytopathogenic Bacteria Associated with Soft Rot Disease of Girasole Tuber

    Directory of Open Access Journals (Sweden)

    Mamdoh Ewis ISMAIL

    2012-02-01

    Full Text Available During 2010-2011 growing seasons six bacterial isolates were separated from naturally infected girasole plants tubers (Helianthus tuberosus L. cv. �Balady�, showing soft rot, collected from experimental Farm of the Faculty of Agriculture, in El-Minia University, Egypt. Pathogenicity tests showed various virulence for the bacteria isolated from girasole tubers, found pathogenic. These organisms were characterized as rod-shaped, Gram negative, ?-methyl-d-glucoside medium, reducing substances from sucrose, phos, phatase activity and deep cavities on pectate medium. Otherwise, diagnostic tests suggested that the pathogen was Erwinia carotovora ssp. carotovora. The isolated bacteria caused soft rot of wounded tubers when inoculated into tissues. The bacterial isolates were compared for their degree of pathogenicity as well as for differences in specific symptoms, induced in different hosts. The tested isolates could infect several host ranges, such as fruits of apricot, apple, olive, lemon, squash, eggplant and potato tubers, bulbs and garlic and onion cloves, roots radish, carrot, sweet potato and rape. On the other hand, no symptoms were exhibited on pods of bean and cowpea, faba bean, fruits of pepper and tomato. The extracts of experimentally diseased girasole tubers were active in pectinase and also in caboxymethyl cellulose at pH 6 compared to enzyme activities in healthy tissues. Also, the isolated bacteria increased the total and reducing sugars in infected tissues.

  3. Rapid quantitative assessment of Rhizoctonia tolerance in roots of wheat and barley

    Science.gov (United States)

    Rhizoctonia solani AG8, causal agent of Rhizoctonia root rot and bare patch in dryland cereal production systems of the Pacific Northwest, USA and Australia, reduces yields in a wide range of crops. Disease is not consistently controlled by available management practices, and genetic resistance is d...

  4. Suppression of seed rot and preemergence of chickpea by seed treatments with fluorescent pseudomonads in Iran.

    Science.gov (United States)

    Ahmadzadeh, M; Sharifi-Tehrani, A

    2006-01-01

    Species of Pythium isolated from rotted chickpea seeds and damped-off seedlings and chickpea soils at experimental field of Agriculture faculty of Tehran University in Karaj area that caused seed rot and preemergence damping-off of chickpea were Pyhium ultimum var. ultimum. One of the most important of soilborne fungal pathogens of the chickpea in Iran is seed rot and preemergence damping-off caused by Pythium ultimum Trow. Consequently, growers can expect as much as > 80% reduction in stand and yield if measures are not taken to control Pythium. Currently, most commercial seeds of chickpea are treated with pesticides. Fluorescent pseudomonads applied to seed are known to reduce soilborne diseases of chickpea caused by Pythium spp. In this study rotted chickpea seeds and diseased seedlings and soil samples were collected from experimental field in Karaj. Soils and roots used as sources of bacteria were collected from field. Fluorescent pseudomonads were isolated by plating samples on S1 and King's Medium B (KMB). Bacteria were preserved in 0.1 M MgSO4 for long-term storage; and NAG (containing 2% glucose) slants and plates at 4 degrees C short-term storage. Of 20 fluorescent pseudomonads isolated on S1 medium, 2 isolates selected for next tests. All strains significantly increased emergence as compared to the infested control in greenhouse trial; isolate Pf-4 consistently provided the best protection against Pythium. Seedling emergence from all bacteria seed treatments was statistically lower than the chemical treatments. All strains significantly increased fresh weight of chickpea as compared to the infested control in greenhouse trial. Seed treatment with metalaxyl were statistically better than captan in sterilized soil. In nonsterilized soil collected from the field artificially infested with P. ultimum, all strains significantly increased fresh weight of chickpea as compared to the infested control in greenhouse trial. Seedling emergence from seed treatment

  5. QTLs for Resistance to Major Rice Diseases Exacerbated by Global Warming: Brown Spot, Bacterial Seedling Rot, and Bacterial Grain Rot.

    Science.gov (United States)

    Mizobuchi, Ritsuko; Fukuoka, Shuichi; Tsushima, Seiya; Yano, Masahiro; Sato, Hiroyuki

    2016-12-01

    In rice (Oryza sativa L.), damage from diseases such as brown spot, caused by Bipolaris oryzae, and bacterial seedling rot and bacterial grain rot, caused by Burkholderia glumae, has increased under global warming because the optimal temperature ranges for growth of these pathogens are relatively high (around 30 °C). Therefore, the need for cultivars carrying genes for resistance to these diseases is increasing to ensure sustainable rice production. In contrast to the situation for other important rice diseases such as blast and bacterial blight, no genes for complete resistance to brown spot, bacterial seedling rot or bacterial grain rot have yet been discovered. Thus, rice breeders have to use partial resistance, which is largely influenced by environmental conditions. Recent progress in molecular genetics and improvement of evaluation methods for disease resistance have facilitated detection of quantitative trait loci (QTLs) associated with resistance. In this review, we summarize the results of worldwide screening for cultivars with resistance to brown spot, bacterial seedling rot and bacterial grain rot and we discuss the identification of QTLs conferring resistance to these diseases in order to provide useful information for rice breeding programs. PMID:27178300

  6. Black rings

    International Nuclear Information System (INIS)

    A black ring is a five-dimensional black hole with an event horizon of topology S1 x S2. We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

  7. Genes of resistance to carrot soft rot in Daucus carota germplasm

    International Nuclear Information System (INIS)

    Erwinia carotovora is a casual agent of soft rot in the carrot. This disease causes severe root losses in the crop, mainly during post-harvest storage but also in the field in the late growing season. Of the many cultivars screened in our department between 1988 and 1990, we found none that was resistant. Consequently, we started to look for sources of resistance genes among wild Daucus carota subspecies. Resistant plants were used for callus production, which will constitute the material for in vitro selection. Resistance to Erwinia carotovora is rather rare. Proof of this is research on the potato, which has been conducted for many years and where the only source of resistance that has been found is the wild species Solanumb brevidens. 3 refs

  8. Maize Stalk Rot and Ear Rot in China%中国玉米茎基腐病和穗腐病研究进展

    Institute of Scientific and Technical Information of China (English)

    徐书法; 陈捷; 高增贵; 邹庆道; 纪明山; 刘海南

    2006-01-01

    This review provides a broad overview of etiology, mechanism of pathogenesis and host resistance and IPM strategies involved in maize stalk rot and ear rot diseases in China. Some different viewpoints in the past are discussed in etiology of stalk rot occurring in China. The relation of both diseases is particularly evaluated based on Fusarium polymorphism analysis at the level of soluble protein, serology, isozymes and DNA, which are also further analyzed in accordance with the knowledge obtained by tracing pathogen infection process within the host root and stem tissue and trapping airborne spores nearby corn plants in the field. The recent researches of both diseases are summarized in physiological and biochemical mechanism of host resistance and resistant genetics, as well as IPM measures centered mainly in the application of biological control agents are summarized.%本文综述了我国在玉米茎基腐病和穗腐病病原学、致病性和寄主抗性机制与综合治理的研究进展.深入探讨了以往我国学者关于引起茎基腐病病原学的不同观点.根据2种病害的病原镰孢菌在可溶性蛋白质、血清学、同功酶和DNA等不同水平的多态性分析,镰孢菌在寄主根和茎组织内侵染过程示踪和孢子捕捉试验结果,重点讨论了2种镰孢菌病害在病原学侵染规律方面的相互关系,概述了2种病害寄主抗性生理生化机理、抗性遗传和以生物防治为核心的综合治理措施研究进展.

  9. Root resorption

    DEFF Research Database (Denmark)

    Kjaer, Inger

    2014-01-01

    Introduction: This paper summarizes the different conditions, which have a well-known influence on the resorption of tooth roots, exemplified by trauma and orthodontic treatment. The concept of the paper is to summarize and explain symptoms and signs of importance for avoiding resorption during...... orthodontic treatment. The Hypothesis: The hypothesis in this paper is that three different tissue layers covering the root in the so-called periroot sheet can explain signs and symptoms of importance for avoiding root resorption during orthodontic treatment. These different tissue layers are; outermost......-an ectodermal tissue layer (Malassez′s epithelium), a middle layer-composed by the collagen-mesodermal tissue layer, and an innermost root-close innervation layer. Abnormalities in one of these tissue layers are thought to cause inflammatory processes in the periodontal membrane comparable to inflammatory...

  10. Genetic variation between Phytophthora cactorum isolates differing in their ability to cause crown rot in strawberry

    OpenAIRE

    Eikemo, H; Klemsdal, S.S.; Riisberg, I.; Bonants, P.J.M.; Stensvand, A.; Tronsmo, A.M.

    2004-01-01

    Analysis of 44 isolates of Phytophthora cactorum, isolated from strawberry and other hosts, by AFLP showed that the crown rot pathotype is different from leather rot isolates and from P. cactorum isolated from other hosts. 16 of 23 crown rot isolates, including isolates from Europe, Japan, Australia, and New Zealand, were identical in an analysis based on 96 polymorphic bands from seven primer combinations. Leather rot isolates of strawberry could not be distinguished from isolates from other...

  11. CHARACTERIZATION OF WOOD DECAY BY ROT FUNGI USING COLORIMETRY AND INFRARED SPECTROSCOPY

    OpenAIRE

    Mírian de Almeida Costa; Alexandre Florian da Costa; Tereza Cristina Monteiro Pastore; Jez Willian Batista Braga; Joaquim Carlos Gonçalez

    2011-01-01

    Wood samples of marupá (Simarouba amara) and andiroba (Carapa guianenis) were submitted to Trametes versicolor (white rot) and Gloeophylum trabeum (brown rot) fungi attack. Colorimetry was used to determine the color of the wood before and after wood decaying fungi. To evaluate the changes in chemical compounds levels in the wood samples, the diffuse reflectance medium infrared spectroscopy was used. Both wood were non resistant against white rot fungus, while with brown rot attack andiroba w...

  12. Persistence of Gliocephalotrichum spp. causing fruit rot of rambutan (Nephelium lappaceum L.) in Puerto Rico

    Science.gov (United States)

    Worldwide, fruit rot of rambutan is an important problem that limits the storage, marketing and long-distance transportation of the fruit. A complex of pathogens has been reported to cause fruit rot of rambutan and significant post-harvest economic losses. During 2009 and 2011 rambutan fruit rot was...

  13. Genetic variation between Phytophthora cactorum isolates differing in their ability to cause crown rot in strawberry

    NARCIS (Netherlands)

    Eikemo, H.; Klemsdal, S.S.; Riisberg, I.; Bonants, P.J.M.; Stensvand, A.; Tronsmo, A.M.

    2004-01-01

    Analysis of 44 isolates of Phytophthora cactorum, isolated from strawberry and other hosts, by AFLP showed that the crown rot pathotype is different from leather rot isolates and from P. cactorum isolated from other hosts. 16 of 23 crown rot isolates, including isolates from Europe, Japan, Australia

  14. Microcanonical Quantum Statistics of Schwarzschild Black Holes

    OpenAIRE

    Scharf, G"unter

    1997-01-01

    It is shown that a quantized Schwarzschild black hole, if described by a square root energy spectrum with exponential multiplicity, can be treated as a microcanonical ensemble without problem leading to the expected thermodynamical properties.

  15. Fungicide seed treatment and host resistance for the management of wheat crown rot caused by Fusarium culmorum

    Directory of Open Access Journals (Sweden)

    Shree R Pariyar

    2014-11-01

    Full Text Available Seed treatment of wheat with the fungicide thiabendazole on the development of crown rot caused by Fusarium culmorum was evaluated on six wheat genotypes with different genetic sources of resistance under controlled conditions in a growth chamber. Seed of three susceptible (S cultivars, Seri 82 (Spring bread wheat, Kiziltan 91 (Winter durum Wheat, and Demir 2000 (Winter bread wheat and three moderately resistant (MR wheat lines, 2-49 (Spring bread wheat, Altay 2000 (Winter bread wheat, and Burbot-6 (Winter bread wheat were treated with thiabendazole at concentrations of 25, 50 and 100 g ai per 100 kg seeds. Thiabendazole seed treatment caused a significant (P< 0.05 reduction in severity of crown rot on 4 out of the 6 wheat genotypes. The highest crown score reduction was recorded on S genotypes Seri 82 and Demir 2000. Thiabendazole at 100 g ai per 100 kg seed gave the highest CS reduction on both the S and MR wheat genotypes. Seed coating with thiabendazole did not show any effect on plant height, plant weight, root length and root weight. No phytotoxicity symptoms were observed at any concentration of the fungicide.

  16. Black Consciousness

    Science.gov (United States)

    Hraba, Joseph; Siegman, Jack

    1974-01-01

    Black militancy is treated as an instance of class consciousness with criteria and scales developed to measure black consciousness and "self-placement" into black consciousness. These dimensions are then investigated with respect to the social and symbolic participation in the ideology of the black movement on the part of a sample of black…

  17. Examining African self-consciousness and Black racial identity as predictors of Black men's psychological well-being.

    Science.gov (United States)

    Pierre, Martin R; Mahalik, James R

    2005-02-01

    This study investigated African self-consciousness and Black racial identity as predictors of psychological distress and self-esteem for Black men. One hundred thirty Black men from a college and community sample completed the African Self-Consciousness Scale, the Racial Identity Attitude Scale-B, the Symptom Checklist 90-Revised, and the Coopersmith Self-Esteem Inventory. Canonical correlation analysis found 2 significant roots with the 1st root indicating that Black men whose attitudes reflected Preencounter and Immersion racial identity attitudes and who do not resist against anti-African/Black forces reported greater psychological distress and less esteem. Results from the 2nd root suggested that Black men whose attitudes reflect greater Internalization racial identity attitudes, greater resistance to anti-African/Black forces, and less identification with Blacks reported greater self-esteem. PMID:15727493

  18. Sclerotium Rot of Sponge Gourd Caused by Sclerotium rolfsii

    OpenAIRE

    Yong Hwan Lee; Jinwoo Kim; Jin-Hyeuk Kwon; Hong-Sik Shim

    2012-01-01

    Sclerotium rot of sponge gourd occurred at the experimental field of Gyeongsangnam-do AgriculturalResearch and Extension Services in August 2010. The infected fruits showed water-soaked and rot symptoms.White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. Thesclerotia were globoid in shape, 1−3 mm in size and white to brown in color. The optimum temperature formycelial growth and sclerotia formation on PDA was 30oC and the hyphal width was 4−8 μ...

  19. Automated Root Tracking with "Root System Analyzer"

    Science.gov (United States)

    Schnepf, Andrea; Jin, Meina; Ockert, Charlotte; Bol, Roland; Leitner, Daniel

    2015-04-01

    Crucial factors for plant development are water and nutrient availability in soils. Thus, root architecture is a main aspect of plant productivity and needs to be accurately considered when describing root processes. Images of root architecture contain a huge amount of information, and image analysis helps to recover parameters describing certain root architectural and morphological traits. The majority of imaging systems for root systems are designed for two-dimensional images, such as RootReader2, GiA Roots, SmartRoot, EZ-Rhizo, and Growscreen, but most of them are semi-automated and involve mouse-clicks in each root by the user. "Root System Analyzer" is a new, fully automated approach for recovering root architectural parameters from two-dimensional images of root systems. Individual roots can still be corrected manually in a user interface if required. The algorithm starts with a sequence of segmented two-dimensional images showing the dynamic development of a root system. For each image, morphological operators are used for skeletonization. Based on this, a graph representation of the root system is created. A dynamic root architecture model helps to determine which edges of the graph belong to an individual root. The algorithm elongates each root at the root tip and simulates growth confined within the already existing graph representation. The increment of root elongation is calculated assuming constant growth. For each root, the algorithm finds all possible paths and elongates the root in the direction of the optimal path. In this way, each edge of the graph is assigned to one or more coherent roots. Image sequences of root systems are handled in such a way that the previous image is used as a starting point for the current image. The algorithm is implemented in a set of Matlab m-files. Output of Root System Analyzer is a data structure that includes for each root an identification number, the branching order, the time of emergence, the parent

  20. Root canal

    Science.gov (United States)

    Endodontic therapy ... the root of a tooth. Generally, there is pain and swelling in the area. The infection can ... You may have some pain or soreness after the procedure. An over-the-counter anti-inflammatory drug, such as ibuprofen or naproxen, can help relieve ...

  1. Root hair mutants of barley

    International Nuclear Information System (INIS)

    Barley mutants without root hairs or with short or reduced root hairs were isolated among M2 seeds of 'Lux' barley (Hordeum vulgare L.) after acidified sodium azide mutagenesis. Root hair mutants are investigated intensively in Arabidopsis where about 40 genes are known. A few root hair mutants are known in maize, rice, barley and tomato. Many plants without root hairs grow quite well with good plant nutrition, and mutants have been used for investigations of uptake of strongly bound nutrients like phosphorus, iron, zinc and silicon. Seed of 'Lux' barley (Sejet Plant Breeding, Denmark) were soaked overnight, and then treated with 1.5-millimolarsodium azide in 0.1 molar sodium phosphate buffer, pH 3, for 2.5 hours according to the IAEA Manual on Mutation Breeding (2nd Ed.). After rinsing in tap water and air-drying, the M2 seeds were sown in the field the same day. Spikes, 4-6 per M1 plant, were harvested. The mutation frequency was similar to that obtained with other barley cultivars from which low-phytate mutants were isolated [5]. Seeds were germinated on black filter paper in tap water for 3 or 4 days before scoring for root hair mutants

  2. EVIDENCE FOR CLEAVAGE OF LIGNIN BY A BROWN ROT FUNGUS

    Science.gov (United States)

    Biodegradation by brown-rot fungi is quantitatively one of the most important fates of lignocellulose in nature. It has long been thought that these fungi do not degrade lignin significantly, and that their activities on this abundant aromatic biopolymer are limited to minor oxidative modifications....

  3. Production and degradation of oxalic acid by brown rot fungi

    International Nuclear Information System (INIS)

    Our results show that all of the brown rot fungi tested produce oxalic acid in liquid as well as in semisolid cultures. Gloeophyllum trabeum, which accumulates the lowest amount of oxalic acid during decay of pine holocellulose, showed the highest polysaccharide-depolymerizing activity. Semisolid cultures inoculated with this fungus rapidly converted 14C-labeled oxalic acid to CO2 during cellulose depolymerization. The other brown rot fungi also oxidized 14C-labeled oxalic acid, although less rapidly. In contrast, semisolid cultures inoculated with the white rot fungus Coriolus versicolor did not significantly catabolize the acid and did not depolymerize the holocellulose during decay. Semisolid cultures of G. trabeum amended with desferrioxamine, a specific iron-chelating agent, were unable to lower the degree of polymerization of cellulose or to oxidize 14C-labeled oxalic acid to the extent or at the rate that control cultures did. These results suggest that both iron and oxalic acid are involved in cellulose depolymerization by brown rot fungi

  4. Trichoderma rot on ‘Fallglo’ Tangerine Fruit

    Science.gov (United States)

    In September 2009, brown rot symptoms were observed on ‘Fallglo’ fruit after 7 weeks of storage. Fourteen days prior to harvest, fruit were treated by dipping into one of four different fungicide solutions. Control fruit were dipped in tap water. After harvest, the fruit were degreened with 5 ppm et...

  5. Genome Sequence of Mushroom Soft-Rot Pathogen Janthinobacterium agaricidamnosum.

    Science.gov (United States)

    Graupner, Katharina; Lackner, Gerald; Hertweck, Christian

    2015-01-01

    Janthinobacterium agaricidamnosum causes soft-rot disease of the cultured button mushroom Agaricus bisporus and is thus responsible for agricultural losses. Here, we present the genome sequence of J. agaricidamnosum DSM 9628. The 5.9-Mb genome harbors several secondary metabolite biosynthesis gene clusters, which renders this neglected bacterium a promising source for genome mining approaches. PMID:25883287

  6. Characterisation of erwinias causing blackleg and soft rot in Finland

    OpenAIRE

    Laurila, Jaana; Joutsjoki, Tiina; Lehtinen, Ari; Ahola, Virpi; Hannukkala, Asko; Pirhonen, Minna

    2006-01-01

    Potato stems showing blackleg or wilting were collected during 2003-2004 and the erwinias were isolated based on cavity forming on pectate-containing media followed by anaerobic growth test. Bacteri were also isolated from rotting tubers and from water samples collected from rivers in southern and western Finland.

  7. Phenolic Compound Utilization by the Soft Rot Fungus Lecythophora hoffmannii

    OpenAIRE

    Bugos, Robert C.; Sutherland, John B.; Adler, John H.

    1988-01-01

    Nine phenolic compounds were metabolized by the soft rot fungus Lecythophora hoffmannii via protocatechuic acid and subsequently cleaved by protocatechuate 3,4-dioxygenase as determined by oxygen uptake, substrate depletion, and ring cleavage analysis. Catechol was metabolized by catechol 1,2-dioxygenase. Fungal utilization of these aromatic compounds may be important in the metabolism of wood decay products.

  8. Population Structure of the North American Cranberry Fruit Rot Complex

    Science.gov (United States)

    Cranberry fruit rot is caused by a complex of pathogenic fungi. Variation in the populations within this complex from region to region could delay identification of the causal agents(s) and complicate management strategies. Our objective was to assess genetic variation within the four major fruit ro...

  9. Genome Sequence of Mushroom Soft-Rot Pathogen Janthinobacterium agaricidamnosum

    OpenAIRE

    Graupner, Katharina; Lackner, Gerald; Hertweck, Christian

    2015-01-01

    Janthinobacterium agaricidamnosum causes soft-rot disease of the cultured button mushroom Agaricus bisporus and is thus responsible for agricultural losses. Here, we present the genome sequence of J. agaricidamnosum DSM 9628. The 5.9-Mb genome harbors several secondary metabolite biosynthesis gene clusters, which renders this neglected bacterium a promising source for genome mining approaches.

  10. Calibrating echelle spectrographs with Fabry-Pérot etalons

    Science.gov (United States)

    Bauer, F. F.; Zechmeister, M.; Reiners, A.

    2015-09-01

    Context. Over the past decades hollow-cathode lamps have been calibration standards for spectroscopic measurements. Advancing to cm/s radial velocity precisions with the next generation of instruments requires more suitable calibration sources with more lines and fewer dynamic range problems. Fabry-Pérot interferometers provide a regular and dense grid of lines and homogeneous amplitudes, which makes them good candidates for next-generation calibrators. Aims: We investigate the usefulness of Fabry-Pérot etalons in wavelength calibration, present an algorithm to incorporate the etalon spectrum in the wavelength solution, and examine potential problems. Methods: The quasi-periodic pattern of Fabry-Pérot lines was used along with a hollow-cathode lamp to anchor the numerous spectral features on an absolute scale. We tested our method with the HARPS spectrograph and compared our wavelength solution to the one derived from a laser frequency comb. Results: The combined hollow-cathode lamp/etalon calibration overcomes large distortion (50 m/s) in the wavelength solution of the HARPS data reduction software. The direct comparison to the laser frequency comb shows differences of only 10 m/s at most. Conclusions: Combining hollow-cathode lamps with Fabry-Pérot interferometers can lead to substantial improvements in the wavelength calibration of echelle spectrographs. Etalons can provide economical alternatives to the laser frequency comb, especially for smaller projects.

  11. Detecting cotton boll rot with an electronic nose

    Science.gov (United States)

    South Carolina Boll Rot is an emerging disease of cotton, Gossypium hirsutum L., caused by the opportunistic bacteria, Pantoea agglomerans (Ewing and Fife). Unlike typical fungal diseases, bolls infected with P. agglomerans continue to appear normal externally, complicating early and rapid detectio...

  12. OXIDATION OF PERSISTANT ENVIRONMENTAL POLLUTANTS BY A WHITE ROT FUNGUS

    Science.gov (United States)

    The white rot fungus Phanerochaete chrysosporium degraded DDT [1,1,-bis(4-chlorophenyl)-2,2,2-trichloroethane], 3,4,3',4'-tetrachlorobiphenyl, 2,4,5,2',-4',5'-hexachlorobiphenyl, 2,3,7,8-tetrachlorodibenzo-p-dioxin, lindane (1,2,3,4,5,6-hexachlorocylohexane), and benzo[a]pyrene t...

  13. Control of lettuce bottom rot by isolates of Trichoderma spp

    Directory of Open Access Journals (Sweden)

    Zayame Vegette Pinto

    2014-06-01

    Full Text Available Bottom rot, caused by Rhizoctonia solani AG 1-IB, is an important disease affecting lettuce in Brazil, where its biological control with Trichoderma was not developed yet. The present study was carried out with the aim of selecting Trichoderma isolates to be used in the control of lettuce bottom rot. Forty-six Trichoderma isolates, obtained with baits containing mycelia of the pathogen, were evaluated in experiments carried out in vitro and in vivo in a greenhouse in two steps. In the laboratory, the isolates were evaluated for their capabilities of parasitizing and producing toxic metabolic substances that could inhibit the pathogen mycelial growth. In the first step of the in vivo experiments, the number and the dry weight of lettuce seedlings of the cultivar White Boston were evaluated. In the second step, 12 isolates that were efficient in the first step and showed rapid growth and abundant sporulation in the laboratory were tested for their capability of controlling bottom rot in two repeated experiments, and had their species identified. The majority of the isolates of Trichoderma spp. (76% showed high capacity for parasitism and 50% of them produced toxic metabolites capable of inhibiting 60-100% of R. solani AG1-IB mycelial growth. Twenty-four isolates increased the number and 23 isolates increased the dry weight of lettuce seedlings inoculated with the pathogen in the first step of the in vivo experiments.In both experiments of the second step, two isolates of T. virens, IBLF 04 and IBLF 50, reduced the severity of bottom rot and increased the number and the dry weight of lettuce seedlings inoculated with R. solani AG1-IB. These isolates had shown a high capacity for parasitism and production of toxic metabolic substances, indicating that the in vitro and in vivo steps employed in the present study were efficient in selecting antagonists to be used for the control of lettuce bottom rot.

  14. Root diseases, climate change and biomass productivity

    International Nuclear Information System (INIS)

    Tree growth and yield in eastern boreal spruce fir forests are both greatly affected by root and butt rots. These pests are also prevalent in western coniferous species and boreal-sub-boreal forests. Infections are difficult to detect, but reduced growth, tree mortality, wind throw and scaled butt cull contribute to considerable forest gaps. Harvesting and stand tending practices in second growth stands are creating conditions for increased incidence. Tree stress is one of the major factors affecting the spread of root disease. It is expected that climate change will create abnormal stress conditions that will further compound the incidence of root disease. A comparison was made between natural and managed stands, including harvesting and stand practices such as commercial thinning. Studies of Douglas-fir forests in British Columbia were presented, with results indicating that managed forests contain one third to one half less carbon biomass than unmanaged forests. It was concluded that root diseases must be recognized and taken into account in order to refine and improve biomass estimates, prevent overestimation of wood supply models and avoid potential wood fibre losses. 40 refs., 2 figs.

  15. Podridão basal pós-colheita do coco verde no estado do Ceará Post-harvest basal rot of coconut fruits in the State of Ceará, Brazil

    OpenAIRE

    Francisco M. P Viana; FRANCISCO C.O. FREIRE; Beatriz M Barguil; Ricardo E Alves; ANTONIO A. SANTOS; JOSÉ E. CARDOSO; Julio C. Vidal

    2002-01-01

    A new post-harvest disease of coconut (Cocos nucifera) was recently detected in fruits exported to European countries. The main symptoms are the blacking and cracking of basal parts of the fruits. Water oozing may occurs as the infection progresses. The fungus Lasiodiplodia theobromae has been frequently isolated from the lesions. Inoculation tests proved that this pathogen is the causal agent of the coconut fruit basal rot. This is the first occurrence of this post-harvest disease in Brazil.

  16. Black Eye

    Science.gov (United States)

    ... eyesight if not treated. If both eyes are black after a head injury, it could signify a skull fracture or other serious injury. Next Black Eye Symptoms Related Ask an Ophthalmologist Answers How ...

  17. Black tea

    Science.gov (United States)

    ... diuretic to increase urine flow. Some people use black tea for preventing tooth decay and kidney stones. In combination with various other products, black tea is used for weight loss. In foods, ...

  18. Locally Finite Root Supersystems

    OpenAIRE

    YOUSOFZADEH, Malihe

    2013-01-01

    We introduce the notion of locally finite root supersystems as a generalization of both locally finite root systems and generalized root systems. We classify irreducible locally finite root supersystems.

  19. Leptin receptor overlapping transcript (LepROT) gene participates in insulin pathway through FoxO.

    Science.gov (United States)

    Wang, Chuan-Xu; Zhao, Ai-Hua

    2016-08-01

    Leptin receptor overlapping transcript (LepROT) is co-transcribed with the leptin receptor (LepR). However, the function and mechanism of LepROT in insulin pathway is unclear. In this study, we report the function of LepROT in maintaining consistent FoxO transcription. LepROT is constitutively expressed during larval development. 20-Hydroxyecdysone, methoprene, and insulin have no effect on the transcription of LepROT. However, the knockdown of LepROT by dsRNA injection in larvae causes delay of the development of Helicoverpa armigera. Knockdown of LepROT results in the upregulation of FoxO and downregulation of PI3K. The knockdown of LepROT also results in the subcellular translocation of FoxO from cytoplasm to nuclei. By contrast, overexpression of LepROT in the HaEpi cell line inhibits FoxO expression. Results suggest that LepROT participates in insulin signaling. PMID:27106118

  20. Black Holes

    Science.gov (United States)

    Luminet, Jean-Pierre

    1992-09-01

    Foreword to the French edition; Foreword to the English edition; Acknowledgements; Part I. Gravitation and Light: 1. First fruits; 2. Relativity; 3. Curved space-time; Part II. Exquisite Corpses: 4. Chronicle of the twilight years; 5. Ashes and diamonds; 6. Supernovae; 7. Pulsars; 8. Gravitation triumphant; Part III. Light Assassinated: 9. The far horizon; 10. Illuminations; 11. A descent into the maelstrom; 12. Map games; 13. The black hole machine; 14. The quantum black hole; Part IV. Light Regained: 15. Primordial black holes; 16. The zoo of X-ray stars; 17. Giant black holes; 18. Gravitational light; 19. The black hole Universe; Appendices; Bibliography; Name index; Subject index.

  1. Control of Postharvest Fusarium Rot and Trichothecium Rot in Harvested Muskmelon (cv. Yindi) by Harpin

    Institute of Scientific and Technical Information of China (English)

    GE Yong-hong; BI Yang; LI Mei; LI Xuan

    2005-01-01

    Preharvest and postharvest application of Harpin was evaluated for its ability to induce resistance in muskmelon fruit and control rots. Preharvest treatments were 30 mg L-1, 60 mg L-1 Harpin or 1 mg L-1 Imazalil either 1 week or 1 day before harvest.The CK was untreated. Fruit were then inoculated with Fusarium semitectum or Trichothecium roseum 48 h after harvest,and stored at 23 ± 1℃, RH (relative humidity) 50-60% for 4 d. All treatments were effective in reducing the lesion area with 60 mg L-1 Harpin the most effectively. No treatments inhibited infection rate. Postharvest treatment was fruit dips of 30 mg L-1, 60 mg L-1 Harpin, 0.1 mg L-1 Imazalil. Fruit were inoculated with F. semitectum or T. roseum 24, 72, 120 or 168 h after treatment, and stored at 23 ± 1 ℃, RH 50-60% for 4 days. All treatments were effective in reducing the lesion area with 60 mg L-1 Harpin the most effectively. No treatments inhibited the infection rate. Postharvest Harpin treatment induced the peroxidase activity increase, peroxidase activity reached maximum after 8 d and the activation lasted at least 10 d.

  2. Biological control of Black Pod Disease and Seedling Blight of cacao caused by Phytophthora Species using Trichoderma from Aceh Sumatra

    Science.gov (United States)

    The cocoa tree, Theobroma cacao L., suffers large yield losses in Aceh Indonesia to the disease black pod rot, caused by Phytophthora spp. Despite having the largest area under cacao production in Sumatra, farmers in the Aceh region have low overall production because of losses to insect pests and b...

  3. Derivation of Mutants of Erwinia carotovora subsp. betavasculorum Deficient in Export of Pectolytic Enzymes with Potential for Biological Control of Potato Soft Rot

    OpenAIRE

    Costa, José M.; Loper, Joyce E.

    1994-01-01

    Erwinia carotovora subsp. betavasculorum Ecb168 produces an antibiotic(s) that suppresses growth of the related bacterium Erwinia carotovora subsp. carotovora in culture and in wounds of potato tubers. Strain Ecb168 also produces and secretes pectolytic enzymes and causes a vascular necrosis and root rot of sugar beet. Genes (out) involved in secretion of pectolytic enzymes by Ecb168 were localized to two HindIII fragments (8.5 and 10.5 kb) of Ecb168 genomic DNA by hybridization to the cloned...

  4. Pengaruh Penambahan Jamur Pelapuk Putih (White Rot Fungi pada Proses Pengomposan Tandan Kosong Kelapa Sawit

    Directory of Open Access Journals (Sweden)

    Nasrul Nasrul

    2010-12-01

    Full Text Available Composting is nowadays a general treatment method for agriculture waste such as empty fruit bunch. This research article reported the composting process of the empty fruit bunches. The effect of addition of white rot fungi (Phanerochaete Chrysosporium as an activator on composting product was studied. Experiment results indicated that white rot fungi is a good activator to improve degradation process of the empty fruit bunch become an organic fertilizer. White rot fungi has capable to increase composting period become shorter in compare with original composting without addition of white rot fungi. The organic fertilizer product as regulation issued by the Standar Nasional Indonesia (NSI can be achieved in duration of 3 months, while for original process without addition of white rot fungi longer degradation time is necessary. Keyword: Composting, empty fruit bunch, white rot fungi

  5. Fusarium rot of onion and possible use of bioproduct

    Directory of Open Access Journals (Sweden)

    Klokočar-Šmit Zlata

    2008-01-01

    Full Text Available Several species of Fusarium are causal agents of onion rot in field and storage. Most prevalent are F. oxysporum f. sp. cepae and F. solani, and recently F. proliferatum, a toxigenic species. Most frequently isolated fungi in our field experiments were F. solani and F. proliferatum with different pathogenicity. Certain differences in antagonistic activity of Trichoderma asperellum on different isolates of F. proliferatum and F. solani have been found in in vitro study in dual culture, expressed as a slower inhibition of growth of the former, and faster of the latter pathogen. Antagonistic abilities of species from genus Trichoderma (T. asperellum are important, and have already been exploited in formulated biocontrol products in organic and conventional production, in order to prevent soil borne pathogens inducing fusarium wilt and rot. The importance of preventing onion infection by Fusarium spp., possible mycotoxin producers, has been underlined.

  6. Identification of potential protein markers of noble rot infected grapes.

    Science.gov (United States)

    Lorenzini, Marilinda; Millioni, Renato; Franchin, Cinzia; Zapparoli, Giacomo; Arrigoni, Giorgio; Simonato, Barbara

    2015-07-15

    The evaluation of Botrytis cinerea as noble rot on withered grapes is of great importance to predict the wine sensory/organoleptic properties and to manage the winemaking process of Amarone, a passito dry red wine. This report describes the first proteomic analysis of grapes infected by noble rot under withering conditions to identify possible markers of fungal infection. 2-D gel electrophoresis revealed that protein profiles of infected and not infected grape samples are significantly different in terms of number of spots and relative abundance. Protein identification by MS analysis allowed to identify only in infected berries proteins of B. cinerea that represent potential markers of the presence of the fungus in the withered grapes. PMID:25722151

  7. The presence and survival of soft rot (Erwinia) in flower bulb production systems

    OpenAIRE

    Doorn, van, MGLM; Vreeburg, P.J.M.; van, Leeuwen, M.; Dees, R.H.L.

    2011-01-01

    Soft rot is causing increasing damage in the flower bulb industry. Bulbous ornamentals such as Hyacinthus, Dahlia, Iris, Muscari, Freesia and Zantedeschia can be infected. Soft rot in flower bulbs is mainly caused by Dickeya spp. (Dickeya spp.) and Erwinia carotovora subsp. carotovora (Pectobacterium carotovorum spp. carotovorum).To identify and detect these soft rot bacterial species in several bulbous ornamentals, standard PCR methods were used. During the last four years, research was dire...

  8. Soft Rot on Citrus unshiu Caused by Rhizopus oryzae in Korea

    OpenAIRE

    Jin-Hyeuk Kwon; Jinwoo Kim; Jae-Wook Hyun; Yong Hwan Lee; Hong-Sik Shim

    2011-01-01

    Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the c...

  9. Rot detection of wood poles by means of a portable x-ray computed tomographic scanner

    International Nuclear Information System (INIS)

    A portable X-ray computed tomographic (CT) scanner has been applied to rot detection of wood poles for electric power distribution. CT reconstructions clearly drew a rotted part and they well agreed with crosssections of wood poles which were actually cut off after the measurement. The result shows that the CT scanner offers a very useful means for rot detection of utility poles, building columns, statues, etc. (author)

  10. The Effect of Temperature and Relative Humidity on Pawpaw Fruit Rot in South-Western Nigeria

    OpenAIRE

    R.A. Baiyewu; N.A. Amusa

    2005-01-01

    Fungi found associated with fruit rot of pawpaw (Carica papaya L. ) in South-western Nigeria includes Rhizopus nigricans, Aspergilus niger, Fusarium moniliforme, Curvularia lunata and Collectotrichum capsicis. All were pathogenic on the test pawpaw fruits varieties (Isolo, JS22 and Homestead) in this study. The most pathogenic being C. lunata followed by R. nigricans, while the least rot was induced by C. capsicis. Results reveal that optimum temperature for maximum rot, range f...

  11. Involvement of phenolic compounds in the susceptibility of bananas to crown rot. A review.

    OpenAIRE

    Lassois, L.; de Lapeyre de Bellaire, L; Ewané, CA.; Lepoivre, P

    2012-01-01

    Crown rot of bananas, caused by a fungal parasitic complex, is one of the main quality defects of exported bananas. Major variations in the susceptibility of bananas to crown rot have been observed in different production zones. The physiological state of the banana fruit at harvest is said to influence its response to pathogenic attack and thus to modulate its susceptibility to crown rot. The susceptibility of bananas to this disease, however, appears to be influenced by many pre-harvest fac...

  12. Pengaruh Penambahan Jamur Pelapuk Putih (White Rot Fungi) pada Proses Pengomposan Tandan Kosong Kelapa Sawit

    OpenAIRE

    Nasrul Nasrul; Teuku Maimun

    2010-01-01

    Composting is nowadays a general treatment method for agriculture waste such as empty fruit bunch. This research article reported the composting process of the empty fruit bunches. The effect of addition of white rot fungi (Phanerochaete Chrysosporium) as an activator on composting product was studied. Experiment results indicated that white rot fungi is a good activator to improve degradation process of the empty fruit bunch become an organic fertilizer. White rot fungi has capable to increa...

  13. Peaches tree genetic divergence for brown rot reaction

    OpenAIRE

    Américo Wagner Júnior; Keli Cristina Fabiane; Jéssica Scarlet Marth Alves de Oliveira; Juliano Zanela; Idemir Citadin

    2011-01-01

    It was evaluated the genetic divergence in peach genotypes for brown rot reaction. It was evaluated 26 and 29 peach genotypes in the 2009/2010 and 2010/2011 production cycle, respectively. The experiment was carried out at the Laboratório de Fitossanidade, da UTFPR - Campus Dois Vizinhos. The experimental design was entirely randomized, considering each peach genotype a treatment, and it was use three replication of nine fruits. The treatment control use three replication of three peach. The ...

  14. Pathogenicity of and plant immunity to soft rot pectobacteria

    OpenAIRE

    Davidsson, Pär R.; Kariola, Tarja; Niemi, Outi; Palva, E. T.

    2013-01-01

    Soft rot pectobacteria are broad host range enterobacterial pathogens that cause disease on a variety of plant species including the major crop potato. Pectobacteria are aggressive necrotrophs that harbor a large arsenal of plant cell wall-degrading enzymes as their primary virulence determinants. These enzymes together with additional virulence factors are employed to macerate the host tissue and promote host cell death to provide nutrients for the pathogens. In contrast to (hemi)biotrophs s...

  15. Botanicals to Control Soft Rot Bacteria of Potato

    OpenAIRE

    Rahman, M.M.; Khan, A. A.; M. E. Ali; Mian, I. H.; Akanda, A. M.; Abd Hamid, S. B.

    2012-01-01

    Extracts from eleven different plant species such as jute (Corchorus capsularis L.), cheerota (Swertia chiraita Ham.), chatim (Alstonia scholaris L.), mander (Erythrina variegata), bael (Aegle marmelos L.), marigold (Tagetes erecta), onion (Allium cepa), garlic (Allium sativum L.), neem (Azadiracta indica), lime (Citrus aurantifolia), and turmeric (Curcuma longa L.) were tested for antibacterial activity against potato soft rot bacteria, E. carotovora subsp. carotovora (Ecc) P-138, under in v...

  16. Soft Rot of Tomato Caused by Mucor racemosus in Korea

    OpenAIRE

    Kwon, Jin-Hyeuk; Hong, Seung-Beom

    2005-01-01

    A soft rot of fruits caused by Mucor racemosus occurred on cherry tomato collected in Agricultural Products Wholesale Market in Jinju, Korea. The disease infection usually occurred wounded areas after cracking of fruits. At first, the lesions started with water soaked and rapidly softened and diseased lesion gradually expanded. Colonies were white to brownish to gray in color. Sporangia were 32~54 µm in size and globose in shape. Sporangiophores were 8~14 µm in width. Sporangiospores were 5~1...

  17. Enzyme activity in banana fruits rotted by Botryodiplodia theobromae Pat.

    OpenAIRE

    Nityananda Chakraborty; Balen Nandi

    2015-01-01

    Peroxidase and polyphenol oxidase activities in fruits of two cultivars of banana, 'champa' and 'kanthali' rotted by Botryodiplodia theobromae Pat. was studied. The enzymes showed much higher activities in infected than that in uninfected 'tissues. Increase in peroxidase activity was evidently inhibited by cycloheximide. Polyphenol oxidase activity was also inhibited in presence of phenylthiourea and Na-diethyldithiocarbamate more strongly by the former. Increase in activities seemed to be du...

  18. Fusarium rot of onion and possible use of bioproduct

    OpenAIRE

    Klokočar-Šmit Zlata; Lević Jelena; Maširević Stevan; Grozdanović-Varga Jelica; Vasić Mirjana; Aleksić Svjetlana

    2008-01-01

    Several species of Fusarium are causal agents of onion rot in field and storage. Most prevalent are F. oxysporum f. sp. cepae and F. solani, and recently F. proliferatum, a toxigenic species. Most frequently isolated fungi in our field experiments were F. solani and F. proliferatum with different pathogenicity. Certain differences in antagonistic activity of Trichoderma asperellum on different isolates of F. proliferatum and F. solani have been found in in vitro study in dual culture, express...

  19. Korrektur von Rot- bzw. Grünanomalie mittels Farbfilter

    OpenAIRE

    Junger, Barbara

    2009-01-01

    Zielsetzung Farbensehen ist ein physiologisches Vermögen basierend unter anderem auf Pigmentgenen, erzeugten Photopigmenten und deren Absorptionsspektren. Im Falle von Störungen des Rot- und Grüngenes resultiert fehlerhaftes Farbensehen im Sinne von anomaler Trichromasie, Dichromasie oder Blauzapfenmonochromasie. Zur Therapie der anomalen Trichromasie wurden korrigierende Farbfilter (Coloryte) mit Spezialbeschichtung entwickelt, deren Einfluss auf das Farbensehen Gegenstand dieser Studie w...

  20. Environmental Factors and Bioremediation of Xenobiotics Using White Rot Fungi

    OpenAIRE

    Magan, Naresh; Fragoeiro, Silvia; Bastos, Catarina

    2010-01-01

    This review provides background information on the importance of bioremediation approaches. It describes the roles of fungi, specifically white rot fungi, and their extracellular enzymes, laccases, ligninases, and peroxidises, in the degradation of xenobiotic compounds such as single and mixtures of pesticides. We discuss the importance of abiotic factors such as water potential, temperature, and pH stress when considering an environmental screening approach, and examples are provided of the ...

  1. Stabilization of lignin peroxidases in white rot fungi by tryptophan.

    OpenAIRE

    Collins, P. J.; Field, J. A.; Teunissen, P; Dobson, A D

    1997-01-01

    Supplementation of various cultures of white rot fungi with tryptophan was found to have a large stimulatory effect on lignin peroxidase activity levels. This enhancement was greater than that observed in the presence of the lignin peroxidase recycling agent veratryl alcohol. Using reverse transcription-PCR, we found that tryptophan does not act to induce lignin peroxidase expression at the level of gene transcription. Instead, the activity enhancement observed is likely to result from the pr...

  2. Rhizosphere microorganisms potential antagonists fusarium sp. causing root rot of passion fruit (passiflora edulis sims)

    OpenAIRE

    Quiroga-Rojas, Luisa Fernanda; Ruiz-Quiñones, Nataly; Muñoz-Motta, Guerly; Lozano-Tovar, María Denis

    2013-01-01

    The passion fruit crop (Passiflora edulis) is very important for the Colombian economy. Nowadays this crop is affected by damping-off disease caused by Fusarium sp. So, it is necessary to look for alternatives which allow us to control the disease efficiently. The bacteria Azotobacter spp., Azoospirillum spp. and the fungi Trichoderma spp., were evaluated as a Fusarium sp. potential biocontrol in In vitro and In vivo test. The research was carried out in laboratory and nursery. The “dual test...

  3. EFFECTS OF PHYTOPHTHORA ROOT ROT AND METALAXYL TREATMENT ON THE YIELD OF SOME FORAGE BRASSICA SPECIES

    OpenAIRE

    Karakaya, Aziz; KOCH, D.W.; Gray, F. A.

    1995-01-01

    Three forage Brassica species were evaluated for their growth and adaptability to the Rocky Mountain region. Brassicas were grown in fields infested with a Phytophthora disease previoıısly observed on kale (Brassica oleracea var. Acephala) Metalaxyl treatmıent did not affect Brassica yields signifıcantly. Although pest problems were detected, Brassica crops tolerated low temperatures and produced excellent yields ( up to 9.90 Mg/ha). The Phytophthora isolates from Brassica, which were identif...

  4. Impact of Heterobasidion spp. root rot in conifer trees and assessment of stump treatment

    OpenAIRE

    Wang, Liying

    2012-01-01

    In the thesis four studies were conducted to understand the impact of Heterobasidion spp. on Picea abies, Pinus sylvestris, and Larix × eurolepis in southern Sweden, and the efficacy of stump treatment against infection in order to economically assess control measures. The ability of secondary spread of H. parviporum inoculated on Norway spruce stumps created at precommercial thinning (PCT) was investigated. Stumps with a minimum diameter of 2.5 cm were able to transfer infection to adjace...

  5. Nematode Control Related to Fusarium Wilt in Soybean and Root Rot and Zinc Deficiency in Corn

    OpenAIRE

    Minton, N. A.; Parker, M. B.; Sumner, D. R.

    1985-01-01

    Nematode and disease problems of irrigated, double-cropped soybean and corn, and zinc deficiency of corn were investigated. Ethylene dibromide, phenamiphos, and aldicarb were equally effective for controlling nematodes and increasing yields of corn planted minimum-till and soybean planted in a moldboard plow prepared seedbed. The residual effects on yields of nematicides applied to the preceeding crop occurred during 3 years for soybean and 1 year for corn. Fusarium wilt symptoms of soybean t...

  6. Isolation and Characterization of Trichoderma spp. for Antagonistic Activity Against Root Rot and Foliar Pathogens.

    Science.gov (United States)

    Kumar, Krishna; Amaresan, N; Bhagat, S; Madhuri, K; Srivastava, R C

    2012-06-01

    Trichoderma, soil-borne filamentous fungi, are capable of parasitising several plant pathogenic fungi. Twelve isolates of Trichoderma spp. isolated from different locations of South Andaman were characterized for their cultural, morphological and antagonistic activity against soil borne and foliar borne pathogens. The sequencing of these isolates showed seven different species. The isolates revealed differential reaction patterns against the test pathogens viz., Sclerotium rolfsii, Colletotrichum gloeosporioides and C. capsici. However, the isolates, TND1, TWN1, TWC1, TGD1 and TSD1 were most effective in percentage inhibition of mycelial growth of test pathogens. Significant chitinase and β-1,3-glucanase activities of all Trichoderma isolates has been recorded in growth medium. T. viride was found with highest chitinase whereas T. harzianum was recorded with highest β-1,3-glucanase activities. PMID:23729873

  7. Evaluation of native bacteria and manganese phosphite for alternative control of charcoal root rot of soybean.

    Science.gov (United States)

    Simonetti, Ester; Viso, Natalia Pin; Montecchia, Marcela; Zilli, Carla; Balestrasse, Karina; Carmona, Marcelo

    2015-11-01

    Plant growth promoting rhizobacteria (PGPR) are potential agents to control plant pathogens and their combined use with biopesticides such as phosphites may constitute a novel strategy to incorporate in disease management programs. In the present study, 11 bacterial isolates were selected on the basis of their antagonistic activity against Macrophomina phaseolina in dual-culture tests, and their plant growth promoting traits. Selected isolates were characterised on the basis of auxin and siderophore production, phosphate solubilisation and rep-PCR genomic fingerprinting. Two of these isolates, identified as Pseudomonas fluorescens 9 and Bacillus subtilis 54, were further evaluated for their inhibitory capacity against M. phaseolina using in vitro (on soybean seeds) and in vivo (greenhouse assay) tests. Both bacteria were applied individually as well as in combined treatment with manganese phosphite as seed treatments. Damage severity on soybean seeds was significantly reduced, compared with the untreated control, by both bacterial strains; however, the individual application of phosphite showed to be least effective in controlling M. phaseolina. Interestingly, the phosphite treatment improved its performance under greenhouse conditions compared to the results from the in vitro assays. In the greenhouse trials, the greatest reductions in disease severity were achieved when strain P. fluorescens 9 was applied singly or when strain B. subtilis 54 was combined with manganese phosphite, achieving 82% of control in both cases. This work is the first to report the control of M. phaseolina using combined treatment with PGPR and phosphite under greenhouse conditions. PMID:26505310

  8. The Use of Antioxidants to Control Root Rot and Wilt Diseases of Pepper

    OpenAIRE

    Montaser Fawzy ABDEL-MONAIM; Mamdoh Ewis ISMAIL

    2010-01-01

    Ten isolates of Fusarium spp were isolated from pepper plants collected from different locations in New Valley Governorate, Egypt. Fusarium solani isolate FP2 and F. oxysporum isolate FP4 were highly pathogenic isolates but the other isolates moderate or less pathogenic to pepper plants (cv. Anaheim-M). The four antioxidant compounds (coumaric acid, citric acid, propylgalate and salicylic acid each at 100 and 200 ppm) were evaluated for their in vitro and in vivo agonist to Fusarium pathogeni...

  9. Role of Bradyrhizobium japonicum and Trichoderma spp. in the control of root rot disease of soybean

    Directory of Open Access Journals (Sweden)

    Syed Ehteshamul-Haque

    2014-08-01

    Full Text Available Seed treatment of soybean with Bndyrhizobium japonicum, Trichoderma harzianum, T. viride, T. hamatum, T. koningii and T. pseudokoningii significantly controlled the infection of 30-day-old seedlingsby Maerophomina phaseolina, Rhizoctonia solani and Fusarium spp. In 60-day-old plants Trichoderma spp.. and B. japonicum inhibited the grouth of R. solani and Fusarium spp., whereas the use of B. japonicum (TAL-102 with T. harzianum. T. viride, T. koningii and T. pseudokoningii controlled the infection by M. phaseolina. Greater grain yield was recorded when B. japonium (TAI-102 was used with T. hamatum.

  10. Identification of Rhizoctonia solani isolates from sugar beet roots by analyzing the ITS region of ribosomal DNA

    Directory of Open Access Journals (Sweden)

    Stojšin Vera B.

    2007-01-01

    Full Text Available Rhizoctonia solani (Kühn is one of the most important sugar beet pathogens Rhizoctonia solani anastomosis groups (AGs 2-2 and 4 are proven to be the most common pathogenic strains on sugar beet. AG 2-2 (intraspecific groups IIIB and IV can cause root and crown rot while damping-off of seedlings is most frequently attributed to AG 4. Four isolates of R. solani from sugar beet roots showing characteristic crown and root rot symptoms, collected from different localities in Vojvodina Province, were chosen and compared to the well-characterized R. solani isolate R9, AG 2-2 IV, from the USA. All Vojvodinian isolates showed medium level of pathogenicity and were able to cause crown and root rot symptoms on inoculated sugar beet roots. Based on anastomosis reaction, isolates from Vojvodina did not belong to the AG 2-2 group. Sequencing of the ITS (internal transcribed spacer region of ribosomal DNA was performed on the Vojvodinian isolates from R9 in order to determine their relatedness. Sequence analysis showed that these isolates were different than R9 and were closely related (99-100% sequence homology to anastomosis group 4, subgroup HG II.

  11. Eradicant and curative treatments of hexanal against peach brown rot

    Directory of Open Access Journals (Sweden)

    Juliana Silveira Baggio

    2014-02-01

    Full Text Available Brown rot, caused by Monilinia spp. , is one of the most important peach (Prunuspersica (L. Batsch diseases and the main cause of postharvest losses. Currently, alternative methods for postharvest disease control, such as the use of volatiles, are under investigation. The objective of this study was to determine the effects of hexanal on the in vitro development of Monilinia fructicola and M. laxa and on monocyclic components of brown rot on peaches. To evaluate the effect on pathogen development in vitro, a single dose of 215 µL of liquid hexanal was placed on glass jars in closed plastic containers (4.3 L at the moment of fungi transfer, 24 or 48 h after transferring to Petri dishes. After hexanal application, the Petri dishes were kept inside the containers that were closed for 24 h at 20 ºC. Mycelial growth was measured seven days after hexanal removal. For in vivo assays, inoculated fruits were kept in closed plastic containers, and hexanal was applied at the moment of fruit inoculation or 24 hours thereafter. The monocyclic components infection frequency, expressed as brown rot incidence, lesion diameter and lesion sporulation, were assessed daily for seven days. Overall, hexanal was more effective in inhibiting mycelial growth when applied at the moment of pathogen transfer. Hexanal did not prevent pathogen infection, but reduced lesion diameter and completely inhibited spore production on the fruit for both treatments. Hexanal provides a promising alternative for chemical control and can be used in postharvest handling systems.

  12. ISOLATION AND IDENTIFICATION OF BACTERIAL CAUSING SOFT ROT DESEASE ON STRAWBERRY FRUIT (Fragaria x ananassa)

    OpenAIRE

    Made Mega Yuliasari; Retno Kawuri; Meitini Wahyuni Proborini

    2015-01-01

    Soft rot on strawberry fruit was found in strawberry (F. x ananassa) plantation in Candi Kuning, Bedugul, Bali. Soft rot on strawberry fruit can be caused by microorganism i.e. bacteria. Objectives of the research were to isolate pathogen causing soft rot on strawberry fruit with plating method and to identify bacteria causing soft rot by using Kit MicrogenTM GNA+B-ID System and Bergey’s Manual of Determinative Bacteriology reference (Holt et al., 1994). Results showed there were five isolate...

  13. Detection of potato brown rot and ring rot by electronic nose: from laboratory to real scale.

    Science.gov (United States)

    Biondi, E; Blasioli, S; Galeone, A; Spinelli, F; Cellini, A; Lucchese, C; Braschi, I

    2014-11-01

    A commercial electronic nose (e-nose) equipped with a metal oxide sensor array was trained to recognize volatile compounds emitted by potatoes experimentally infected with Ralstonia solanacearum or Clavibacter michiganensis subsp. sepedonicus, which are bacterial agents of potato brown and ring rot, respectively. Two sampling procedures for volatile compounds were tested on pooled tubers sealed in 0.5-1 L jars at room temperature (laboratory conditions): an enrichment unit containing different adsorbent materials (namely, Tenax(®) TA, Carbotrap, Tenax(®) GR, and Carboxen 569) directly coupled with the e-nose (active sampling) and a Radiello(™) cartridge (passive sampling) containing a generic Carbograph fiber. Tenax(®) TA resulted the most suitable adsorbent material for active sampling. Linear discriminant analysis (LDA) correctly classified 57.4 and 81.3% total samples as healthy or diseased, when using active and passive sampling, respectively. These results suggested the use of passive sampling to discriminate healthy from diseased tubers under intermediate and real scale conditions. 80 and 90% total samples were correctly classified by LDA under intermediate (100 tubers stored at 4°C in net bag passively sampled) and real scale conditions (tubers stored at 4°C in 1.25 t bags passively sampled). Principal component analysis (PCA) of sensorial analysis data under laboratory conditions highlighted a strict relationship between the disease severity and the responses of the e-nose sensors, whose sensitivity threshold was linked to the presence of at least one tuber per sample showing medium disease symptoms. At intermediate and real scale conditions, data distribution agreed with disease incidence (percentage of diseased tubers), owing to the low storage temperature and volatile compounds unconfinement conditions adopted. PMID:25127615

  14. Black Culture

    Directory of Open Access Journals (Sweden)

    Angela Khristin Brown

    2013-07-01

    Full Text Available The migration of blacks in North America through slavery became united.  The population of blacks past downs a tradition of artist through art to native born citizens. The art tradition involved telling stories to each generation in black families. The black culture elevated by tradition created hope to determine their personal freedom to escape from poverty of enslavement and to establish a way of life through tradition. A way of personal freedoms was through getting a good education that lead to a better foundation and a better way of life. 

  15. Afrokoko Roots

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Give us a little background information about Afrokoko Roots.How long have you been performing together?It's an international Afrobeat outfit that I founded in Beijing three years ago.I founded it in order to show Chinese people that Africa is beyond what they see and hear on TV.For the purpose of cultural exchange,I hope it can help the Chinese learn about African culture,music,fashion,history and much more.Our band features two dancers,two backup singers,two percussionists,four brass players,a keyboard player,a guitar player and a drummer- and me as the lead vocal,drummer and dancer,which makes for live performances that are equally exciting sonically as they are visually.We have been traveling around,and so far,we have toured and performed in many Chinese cities such as Dalian (Liaoning Province),Hohhot (Inner Mongolia Autonomous Region) and Haikou (Hainan Province).

  16. Carbon Dioxide and Methane Formation in Norway Spruce Stems Infected by White-Rot Fungi

    Directory of Open Access Journals (Sweden)

    Ari M. Hietala

    2015-09-01

    Full Text Available Globally, billions of tons of carbon sequestered in trees are annually recycled back to the atmosphere through wood decomposition by microbes. In Norway, every fifth Norway spruce shows at final harvest infection by pathogenic white-rot fungi in the genera Heterobasidion and Armillaria. As these fungi can mineralize all components of wood, we predicted that they have a significant carbon footprint. Gas samples taken from infected stems were analyzed for CO2 and CH4 concentrations, and wood samples from different parts of the decay columns were incubated under hypoxic (4% O2 and anoxic laboratory conditions. In spring and summer the stem concentrations of CO2 were generally two times higher in trees with heartwood decay than in healthy trees. For most of the healthy trees and trees with heartwood decay, mean stem concentrations of CH4 were comparable to ambient air, and only some Armillaria infected trees showed moderately elevated CH4. Consistently, low CH4 production potentials were recorded in the laboratory experiment. Up-scaling of CO2 efflux due to wood decay in living trees suggests that the balance between carbon sequestration and emission may be substantially influenced in stands with high frequency of advanced root and stem heartwood decay.

  17. Are black holes totally black?

    CERN Document Server

    Grib, A A

    2014-01-01

    Geodesic completeness needs existence near the horizon of the black hole of "white hole" geodesics coming from the region inside of the horizon. Here we give the classification of all such geodesics with the energies $E/m \\le 1$ for the Schwarzschild and Kerr's black hole. The collisions of particles moving along the "white hole" geodesics with those moving along "black hole" geodesics are considered. Formulas for the increase of the energy of collision in the centre of mass frame are obtained and the possibility of observation of high energy particles arriving from the black hole to the Earth is discussed.

  18. Developmental and metabolic plasticity of white-skinned grape berries in response to botrytis cinerea during noble rot

    OpenAIRE

    Blanco-Ulate, B; Amrine, KCH; Collins, TS; Rivero, RM; Vicente, AR; Morales-Cruz, A; Doyle, CL; Ye, Z.; Allen, G.; Heymann, H; Ebeler, SE; Cantu, D.

    2015-01-01

    © 2015 American Society of Plant Biologists. All rights reserved. Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for ...

  19. First report of brown rot on apple fruit caused by Monilinia fructicola in the United States

    Science.gov (United States)

    Brown rot, caused by Monilinia fructicola (G. Wint.) Honey, is the most devastating disease of stone fruits in North America resulting in significant economic losses. The fungus has been recently reported to cause pre and postharvest brown rot on apple fruit in Germany, Italy, and Serbia. However, M...

  20. Temporal changes in wood crystalline cellulose during degradation by brown rot fungi

    DEFF Research Database (Denmark)

    Howell, Caitlin; Hastrup, Anne Christine Steenkjær; Goodell, Barry;

    2009-01-01

    The degradation of wood by brown rot fungi has been studied intensely for many years in order to facilitate the preservation of in-service wood. In this work we used X-ray diffraction to examine changes in wood cellulose crystallinity caused by the brown rot fungi Gloeophyllum trabeum, Coniophora...

  1. First report of Calonectria hongkongensis causing fruit rot of rambutan (Nephelium lappaceum L.)

    Science.gov (United States)

    Fruit rot is a major pre- and post-harvest disease problem in rambutan orchards. In 2011, fruit rot was observed at the USDA-TARS orchards in Mayaguez, Puerto Rico. Infected fruit were collected and tissue sections (1 mm2) were superficially sterilized with 70% ethanol and 0.5% sodium hypochlorite. ...

  2. The persistence of Gliocephalotrichum bulbilium and G. simplex causing fruit rot of rambutan in Puerto Rico

    Science.gov (United States)

    Fruit rot of rambutan (Nephelium lappaceum L.) is a pre and post-harvest disease problem that affects fruit quality. Significant post-harvest losses have occurred worldwide and several pathogens have been identified in Malaysia, Costa Rica, Hawaii, Thailand, and Puerto Rico. In 2011, fruit rot was o...

  3. Sorghum pathology and biotechnology - A fungal disease perspective: Part II. Anthracnose, stalk rot, and downy mildew

    Science.gov (United States)

    Foliar diseases and stalk rots are among the most damaging diseases of sorghum in terms of lost production potential, thus commanding considerable research time and expenditure. This review will focus on anthracnose, a fungal disease that causes both foliar symptoms and stalk rots along with the st...

  4. The effect of long term storage on bacterial soft rot resistance in potato

    Science.gov (United States)

    Bacterial soft rot is a serious disease in potato (Solanum tuberosum L.), causing rapid tuber tissue maceration and, consequently, marketable yield loss. Soft rot bacteria, especially Pectobacterium carotovorum subsp. carotovorum (Pbc), are favored by moist conditions, which are prevalent in large p...

  5. Control of speck rot in apple fruit caused by Phacidiopycnis washingtonensis with pre- and postharvest fungicides

    Science.gov (United States)

    Speck rot caused by Phacidiopycnis washingtonensis is a recently reported postharvest fruit rot disease of apple. Infection of apple fruit by the fungus occurs in the orchard, but symptoms develop during storage. In this study, selected pre- and postharvest fungicides were evaluated for control of s...

  6. Preharvest applications of fungicides for control of Sphaeropsis rot in stored apples

    Science.gov (United States)

    Sphaeropsis rot caused by Sphaeropsis pyriputrescens is a recently reported postharvest fruit rot disease of apple in Washington State and causes significant economic losses. Infection of apple fruit by the fungus occurs in the orchard, but decay symptoms develop during storage or in the market. The...

  7. Effect of actigard and other new fungicides on phytophthora fruit rot of watermelon

    Science.gov (United States)

    Fruit rot, caused by Phytophthora capsici is an emerging disease in most watermelon producing regions of Southeast U.S. Between 2003 and 2008, we observed many watermelon farms in Georgia, South Carolina, and North Carolina, where growers did not harvest the crop due to severe fruit rot. The Natio...

  8. Effect of Cultural Practices and Fungicides on Phytophthora Fruit Rot of Watermelon in the Carolinas

    Science.gov (United States)

    Phytophthora fruit rot, caused by Phytophthora capsici, is an important and emerging disease of watermelon (Citrullus lanatus) in the Southeastern U.S. To develop strategies to manage Phytophthora fruit rot, we evaluated the effects of two cultural practices (raised bare ground and plastic mulched ...

  9. Response of sugar beet recombinant inbred lines to post-harvest rot fungi

    Science.gov (United States)

    Sugar beet is commonly stored in outdoor piles prior to processing. During this storage period the crop is subject to multiple post-harvest rots. Resistance to three post harvest rots was identified in two sugar beet germplasm in the 1970s, but there has been little work done on host resistance to p...

  10. Response of sugar beet (Beta vulgaris) recombinant inbred lines to post-harvest rot fungi

    Science.gov (United States)

    Sugar beet (Beta vulgaris) is commonly stored in outdoor piles prior to processing for food and animal feed. During this storage period the crop is subject to multiple post-harvest rots. Resistance to three post harvest rots was identified in two sugar beet germplasm in the 1970s, but there has been...

  11. Evaluation of Pseudomonas syringae Strain ESC11 for Biocontrol of Crown Rot and Anthracnose of Banana

    Science.gov (United States)

    Pseudomonas syringae strain ESC11, and 250 'g/ml each of thiabendazole (TBZ) and imazalil reduced crown rot of banana caused by a Fusarium sp. by 0-88% and 73-88%, respectively, in laboratory experiments. ESC11 alone did not significantly reduce rot, mold, or anthracnose in most field trials. TBZ an...

  12. Serpula lacrymans, The Dry Rot Fungus and Tolerance Towards Copper-Based Wood Preservatives

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Jensen, Bo; Clausen, Carol;

    2005-01-01

    brown-rot fungi is thought to be due in part to oxalic acid production and accumulation. Oxalic acid has been implicated in copper tolerance by the formation of copper oxalate crystals. Twelve isolates of the dry rot fungus, S. lacrymans and four other brown rot species were evaluated for weight loss on...

  13. Infection of apple fruit by Sphaeropsis pyriputrescens in the orchard in relation to Sphaeropsis rot in storage

    Science.gov (United States)

    Sphaeropsis rot, caused by Sphaeropsis pyriputrescens, is a recently recognized postharvest fruit rot disease of apple in the United States. The objectives of this study were to determine the timing of apple fruit infection in the orchard in relation to development of Sphaeropsis rot in storage and ...

  14. ISOLATION AND IDENTIFICATION OF BACTERIAL CAUSING SOFT ROT DESEASE ON STRAWBERRY FRUIT (Fragaria x ananassa

    Directory of Open Access Journals (Sweden)

    Made Mega Yuliasari

    2015-03-01

    Full Text Available Soft rot on strawberry fruit was found in strawberry (F. x ananassa plantation in Candi Kuning, Bedugul, Bali. Soft rot on strawberry fruit can be caused by microorganism i.e. bacteria. Objectives of the research were to isolate pathogen causing soft rot on strawberry fruit with plating method and to identify bacteria causing soft rot by using Kit MicrogenTM GNA+B-ID System and Bergey’s Manual of Determinative Bacteriology reference (Holt et al., 1994. Results showed there were five isolates of bacteria (IB-1, IB-2, IB-3, IB-4, and IB-5. Positive result of Postulat Koch showed that bacteria causing soft rot on strawberry is IB-1. Identification that was done by using Kit MicrogenTM GNA+B-ID System and Bergey’s Manual of Determinative Bacteriology reference (Holt et al., 1994, showed that the isolate IB-1 is Weeksella.

  15. Black market

    International Nuclear Information System (INIS)

    One way for states and subnational groups to acquire material, knowledge and equipment necessary to build a nuclear weapon or device are illegal transactions. These were singular in the past and did not cause the development of a nuclear black market. But all necessary components of a functioning black market exist. Therefore the further spread and extension of the use of nuclear power would enhance the threat of a nuclear black market, if the trade and use of specific nuclear material is not abandoned worldwide. (orig.)

  16. Re-imagining South Africa: Black Consciousness, radical Christianity and the New Left, 1967 – 1977

    OpenAIRE

    Macqueen, Ian Martin

    2011-01-01

    This thesis places Black Consciousness in comparative perspective with progressive politics in South Africa in the late 1960s and the 1970s. It argues that the dominant scholarly focus on Black Consciousness, which is passed over as a ‘stage’ in the Black struggle against white supremacy, insufficiently historicises the deeper roots, and the wider resonances and ideological contestations of the Black Consciousness movement. As they refined their political discourse, Black Consciousness activi...

  17. Bacteriophages of Soft Rot Enterobacteriaceae-a minireview.

    Science.gov (United States)

    Czajkowski, Robert

    2016-01-01

    Soft rot Enterobacteriaceae (Pectobacterium spp. and Dickeya spp., formerly pectinolytic Erwinia spp.) are ubiquitous necrotrophic bacterial pathogens that infect a large number of different plant species worldwide, including economically important crops. Despite the fact that these bacteria have been studied for more than 50 years, little is known of their corresponding predators: bacteriophages, both lytic and lysogenic. The aim of this minireview is to critically summarize recent ecological, biological and molecular research on bacteriophages infecting Pectobacterium spp. and Dickeya spp. with the main focus on current and future perspectives in that field. PMID:26626879

  18. Enzyme activity in banana fruits rotted by Botryodiplodia theobromae Pat.

    Directory of Open Access Journals (Sweden)

    Nityananda Chakraborty

    2015-06-01

    Full Text Available Peroxidase and polyphenol oxidase activities in fruits of two cultivars of banana, 'champa' and 'kanthali' rotted by Botryodiplodia theobromae Pat. was studied. The enzymes showed much higher activities in infected than that in uninfected 'tissues. Increase in peroxidase activity was evidently inhibited by cycloheximide. Polyphenol oxidase activity was also inhibited in presence of phenylthiourea and Na-diethyldithiocarbamate more strongly by the former. Increase in activities seemed to be due to increased sytheses of the enzymes. In an in vitro culture, the fungus exhibited some peroxidase but no polyphenoloxidase activity.

  19. Transformation optics with Fabry-Pérot resonances.

    Science.gov (United States)

    Sadeghi, M M; Li, Sucheng; Xu, Lin; Hou, Bo; Chen, Huanyang

    2015-01-01

    Transformation optics is a powerful tool to design various novel devices, such as invisibility cloak. Fantastic effects from this technique are usually accompanied with singular mappings, resulting in challenging implementations and narrow bands of working frequencies. Here in this article, Fabry-Pérot resonances in materials of extreme anisotropy are used to design various transformation optical devices that are not only easy to realize but also work well for a set of resonant frequencies (multiple frequencies). As an example, a prototype of a cylindrical concentrator is fabricated for microwaves. PMID:25726924

  20. Effect of irradiation on the potato tubers rotting during storage

    International Nuclear Information System (INIS)

    The potato tubers subjected to irradiation in autumn were found dry and soft rotting more numerous than non-irradiated ones for the whole period of storage and especially in April and May. The above mentioned phenomenon brought about a little quicker elimination of tubers naturally infected by pectinolytic bacteria. Susceptibility of both kinds of tubers was similar to Fusarium sulphureum introduced under a cover tissue. The irradiation of potato tubers in autumn 1986 led to the appearance of some hard tubers with brown ring spots in spring 1987

  1. X-ray computed tomography uncovers root-root interactions: quantifying spatial relationships between interacting root systems in three dimensions

    Directory of Open Access Journals (Sweden)

    Alexander Martin Paya

    2015-04-01

    Full Text Available Research in the field of plant biology has recently demonstrated that inter- and intra-specific interactions belowground can dramatically alter root growth. Our aim was to answer questions related to the effect of inter- vs. intra-specific interactions on the growth and utilization of undisturbed space by fine roots within three dimensions (3D using micro X-ray computed tomography. To achieve this, Populus tremuloides (quaking aspen and Picea mariana (black spruce seedlings were planted into containers as either solitary individuals, or inter-/intra-specific pairs, allowed to grow for two months, and 3D metrics developed in order to quantify their use of belowground space. In both aspen and spruce, inter-specific root interactions produced a shift in the vertical distribution of the root system volume, and deepened the average position of root tips when compared to intra-specifically growing seedlings. Inter-specific interactions also increased the minimum distance between root tips belonging to the same root system. There was no effect of belowground interactions on the radial distribution of roots, or the directionality of lateral root growth for either species. In conclusion, we found that significant differences were observed more often when comparing controls (solitary individuals and paired seedlings (inter- or intra-specific, than when comparing inter- and intra-specifically growing seedlings. This would indicate that competition between neighboring seedlings was more responsible for shifting fine root growth in both species than was neighbor identity. However, significant inter- vs. intra-specific differences were observed, which further emphasizes the importance of biological interactions in competition studies.

  2. Evaluación de estrés hídrico en plantas de fresa a raíz desnuda Evaluation of water stress on bare-root strawberry plants

    Directory of Open Access Journals (Sweden)

    César Gutiérrez Vaca

    Full Text Available En el estudio realizado se determinó el tiempo disponible antes de aplicar riego vía goteo, después de plantar fresa a raíz desnuda en suelo acolchado con humedad a punto de marchitamiento permanente, sin poner en riesgo de muerte a la planta. Con el propósito de diseñar una trasplantadora para plantas a raíz desnuda que opere sobre suelos secos acolchados. Se analizaron 4 tratamientos de riego; se regó una hora antes del trasplante, al momento del trasplante, 1 y 2 horas después del trasplante. El experimento se llevó a cabo en noviembre de 2007 en la comunidad "El Copal", municipio de Irapuato, Guanajuato, México; donde la altura sobre el nivel del mar es de 1 720 m; el suelo de la región es de textura arcillo-limoso cuya humedad de punto de marchitamiento permanente es alrededor de 18%. El plástico utilizado fue de color blanco al exterior, negro al interior con 30 µm de espesor. Se determinó que es viable aplicar el riego al momento de realizar el trasplante y hasta dos horas después sin exponer la integridad de la planta, con 95% de certidumbre. Se concluye que es posible realizar el trasplante mecanizado de plantas de fresa a raíz desnuda sobre suelo acolchado seco al ambiente, lo que permitirá que la trasplantadora en cuestión pueda operar.This study determined the time available before irrigating, after planting bare-root strawberry plants in soil cushioned with moisture before rotting permanently, without risking the plant's life. This, in order to design a grafting device for bare-root plants that runs on dry cushioned soils.Four irrigation treatments were analyzed; one was applied an hour before transplanting, another when transplanting, and 1 and 2 hours afterwards. The experiment was carried out in November 2007 in the town of "El Copal", in the municipality of Irapuato, Guanajuato, Mexico; the location's height is 1 720 masl; the soil is silty clay loam and the rotting point humidity is around 18%. The plastic

  3. Growth Inhibition of Cocoa Pod Rot Fungus Phytophthora palmivora byPseudomonas fluorescence and Bacillus subtilis bacteria

    Directory of Open Access Journals (Sweden)

    Sakti Widyanta Pratama

    2013-08-01

    Full Text Available Black pod disease caused by Phytophthora palmivorafungus is one of the important diseases on cocoa crop. Pod rot is the most important disease because it may cause loss of cocoa pod. Until now, the fungal pathogen of cocoa black pod disease is still a crucial problem and there is no fungicide that is really effective against the disease. One alternative to control the cocoa black pod disease is by using biological agents as biofungicide, including utilizing Pseudomonas fluorescenceand Bacillus subtilis bacteria. The research was done by isolation of P. palmivora from infected pods of Kaliwining Experimental Station to obtain pure cultures of fungus and by multiplication of P. fluorescence and B. subtilis. Antagonist test was performed by inoculating P. palmivora into a petri dish in a distance of 3 cm from the edge. P. fluorescenceand B. Subtilis were inoculated into petridishes in three days after the fungal treatment. Control was inoculated with isolate of P. palmivora only. Fungal growth was measured everyday by measuring radius of fungal colonies first time 24 hours after inoculation. Growth of Phytophthora palmivora in the two treatmens were used to calculate the percentage of inhibition. The results of this study indicated that P. fluorescence and B. subtiliswere able to inhibit fungal growth of P. palmivora. Both bacterial antagonists had the same effectiveness in inhibiting the growth of P. palmivora fungus based on the percentage of inhibition and effectiveness criteria. Based on the results of translucent zones indicated that B. subtiliswas more powerfull in inhibiting growth of P. Palmivora compared to P. fluorescence. Key words: Black pod disease of cocoa, biological control, Phytophthora palmivora, Pseudomonas fluorescence, Bacillus subtilis

  4. Black tea

    Science.gov (United States)

    ... product containing black tea extract plus green tea extract, asparagus, guarana, kidney bean, and mate along with a combination of kidney bean pods, garcinia, and chromium yeast for 12 weeks does not reduce body weight ...

  5. Electrical Imaging of Roots and Trunks

    Science.gov (United States)

    Al Hagrey, S.; Werban, U.; Meissner, R.; Ismaeil, A.; Rabbel, W.

    2005-05-01

    We applied geoelectric and GPR techniques to analyze problems of botanical structures and even processes, e.g., mapping root zones, internal structure of trunks, and water uptake by roots. The dielectric nature of root zones and trunks is generally a consequence of relatively high moisture content. The electric method, applied to root zones, can discriminate between old, thick, isolated roots (high resistivity) and the network of young, active, and hydraulically conductive zones (low resistivity). Both types of roots show low radar velocity and a strong attenuation caused by the dominant effect of moisture (high dielectric constant) on the electromagnetic wave propagation. Single root branches could be observed in radargrams by their reflection and diffraction parabolas. We have perfected the inversion method for perfect and imperfect cylindrical objects, such as trunks, and developed a new multielectrodes (needle or gel) ring array for fast applications on living trees and discs. Using synthetic models we tested the technique successfully and analyzed it as a function of total electrode number and configuration. Measurements at a trunk show a well established inverse relationship between the imaged resistivity and the moisture content determined from cores. The central resistivity maximum of healthy trees strongly decreases toward the rim. This agrees with the moisture decrease to the outside where active sap flow processes take place. Branching, growth anomalies (new or old shoots) and meteorological effects (sunshine and wind direction) lead to deviations of the concentric electric structure. The strongest anomalies are related to infections causing wet, rotting spots or cavities. The heartwood resistivity is highest in olive and oak trunks, intermediate in young fruit trees and lowest in cork oak trunks that are considered to be anomalously wet. Compared to acoustic tomography our electric technique shows a better resolution in imaging internal ring structures

  6. Neuropharmacological properties of Trichosanthes dioica root

    Institute of Scientific and Technical Information of China (English)

    Sanjib Bhattacharya; Pallab Kanti Haldar

    2013-01-01

    AIM:Trichosanthes dioica Roxb.(Cucurbitaceae),commonly known as pointed gourd in English,is a dioecious climber grown widely in the Indian subcontinent.Traditionally,this plant has been used in India for several medicinal purposes.The present study aimed to evaluate certain neuropharmacological properties of the hydroalcoholic extract of T.dioica root (TDA) in experimental animal models.METHODS:TDA (at 100 and 200 mg.kg-1 body weight,p.o.) was evaluated for anti-noeiceptive activity by the acetic acid-induced writhing and tail flick methods.Locomotor depressant activity was measured by means of an actophotometer.Skeletal muscle relaxant effects were evaluated by using a rots-rod apparatus,and the sedative potentiating property by a phenobarbitone-induced sleep potentiation study.RESULTS:The results of the present study revealed significant (P < 0.001) and dose dependent anti-nociceptive,locomotor depressant,muscle relaxant,and sedative potentiating effects of TDA,demonstrating its depressant action on the central nervous system (CNS).CONCLUSION:From the present study,it can be concluded that T.dioica root possessed prominent anti-nociceptive,as well as depressant,action on the CNS,as manifested by these important neuropharmacological properties in mice.

  7. Root canal irrigants

    OpenAIRE

    Kandaswamy Deivanayagam; Venkateshbabu Nagendrababu

    2010-01-01

    Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

  8. Monilinia species causing brown rot of peach in China.

    Directory of Open Access Journals (Sweden)

    Meng-Jun Hu

    Full Text Available In this study, 145 peaches and nectarines displaying typical brown rot symptoms were collected from multiple provinces in China. A subsample of 26 single-spore isolates were characterized phylogenetically and morphologically to ascertain species. Phylogenetic analysis of internal transcribed spacer (ITS regions 1 and 2, glyceraldehyde-3-phosphate dehydrogenase (G3PDH, β-tubulin (TUB2 revealed the presence of three distinct Monilinia species. These species included Monilinia fructicola, Monilia mumecola, and a previously undescribed species designated Monilia yunnanensis sp. nov. While M. fructicola is a well-documented pathogen of Prunus persica in China, M. mumecola had primarily only been isolated from mume fruit in Japan. Koch's postulates for M. mumecola and M. yunnanensis were fulfilled confirming pathogenicity of the two species on peach. Phylogenetic analysis of ITS, G3PDH, and TUB2 sequences indicated that M. yunnanensis is most closely related to M. fructigena, a species widely prevalent in Europe. Interestingly, there were considerable differences in the exon/intron structure of the cytochrome b (Cyt b gene between the two species. Morphological characteristics, including spore size, colony morphology, lesion growth rate, and sporulation, support the phylogenetic evidence suggesting the designation of M. yunnanensis as a new species. A new multiplex PCR method was developed to facilitate the detection of M. yunnanensis and differentiation of Monilinia spp. causing brown rot of peach in China.

  9. Peaches tree genetic divergence for brown rot reaction

    Directory of Open Access Journals (Sweden)

    Américo Wagner Júnior

    2011-10-01

    Full Text Available It was evaluated the genetic divergence in peach genotypes for brown rot reaction. It was evaluated 26 and 29 peach genotypes in the 2009/2010 and 2010/2011 production cycle, respectively. The experiment was carried out at the Laboratório de Fitossanidade, da UTFPR - Campus Dois Vizinhos. The experimental design was entirely randomized, considering each peach genotype a treatment, and it was use three replication of nine fruits. The treatment control use three replication of three peach. The fruit epidermis were inoculated individually with 0.15 mL of M. fructicola conidial suspension (1.0 x 10(5 spores mL-1. In the control treatment was sprayed with 0.15 mL of distilled water. The fruits were examined 72 and 120 hours after inoculation, and the incidence and severity disease were evaluated. These results allowed realized study for genetic divergence, used as dissimilarity measure the Generalized Mahalanobis distance. Cluster analysis using Tocher´s optimization method and distances in the plan were applied. There was smallest genetic divergence among peach trees evaluated for brown rot, what can difficult to obtain resistance in the genotypes.

  10. Efficient xylose fermentation by the brown rot fungus Neolentinus lepideus.

    Science.gov (United States)

    Okamoto, Kenji; Kanawaku, Ryuichi; Masumoto, Masaru; Yanase, Hideshi

    2012-02-10

    The efficient production of bioethanol on an industrial scale requires the use of renewable lignocellulosic biomass as a starting material. A limiting factor in developing efficient processes is identifying microorganisms that are able to effectively ferment xylose, the major pentose sugar found in hemicellulose, and break down carbohydrate polymers without pre-treatment steps. Here, a basidiomycete brown rot fungus was isolated as a new biocatalyst with unprecedented fermentability, as it was capable of converting not only the 6-carbon sugars constituting cellulose, but also the major 5-carbon sugar xylose in hemicelluloses, to ethanol. The fungus was identified as Neolentinus lepideus and was capable of assimilating and fermenting xylose to ethanol in yields of 0.30, 0.33, and 0.34 g of ethanol per g of xylose consumed under aerobic, oxygen-limited, and anaerobic conditions, respectively. A small amount of xylitol was detected as the major by-product of xylose metabolism. N. lepideus produced ethanol from glucose, mannose, galactose, cellobiose, maltose, and lactose with yields ranging from 0.34 to 0.38 g ethanol per g sugar consumed, and also exhibited relatively favorable conversion of non-pretreated starch, xylan, and wheat bran. These results suggest that N. lepideus is a promising candidate for cost-effective and environmentally friendly ethanol production from lignocellulosic biomass. To our knowledge, this is the first report on efficient ethanol fermentation from various carbohydrates, including xylose, by a naturally occurring brown rot fungus. PMID:22226194

  11. Pharmacognostic and phytochemical investigation of root of Solanum nigrum Linn.: An ethnomedicinally important herb

    OpenAIRE

    Chandrashekhar Yuvaraj Jagtap; Pradeep Kumar Prajapati; Harisha Chinnappa Rudrappa; Shukla, Vinay J.

    2013-01-01

    Background: Roots of Solanum nigrum Linn. (Solanaceae), commonly known as black night shade (Kakamachi), is traditionally used in the treatment of worms and abdominal pain. Until date no scientific evaluation has been reported on its roots. Aim: The present study deals with the microscopical, histochemical, physicochemical, fluorescence analysis, preliminary phytochemical and chromatographic study of roots of S. nigrum L. Materials and Methods: Thin sections of fresh root were used for the mi...

  12. Resistance of Brassica rapa L. and B. napus L. to black rot and leaf spot pathogens

    OpenAIRE

    IGNATOV A.N.; A.M. Artemyeva; Yu.V. Chesnokov; POLITYKO V.A.; E.V. Matveeva; A.A. Oraevskiy; Schaad, N. W.

    2011-01-01

    Изучали географическое и таксономическое распределение расоспецифической устойчивости к фитопатогенным ксантомонадам среди образцов Brassica rapa и B. napus. Выявлено, что устойчивые к расе 4 Xanthomonas campestris Pam. (Dow.) (Xcc) подвиды B. rapa в основном сконцентрированы в Центральной Азии и Японии. Впервые обнаружены доноры комплексной устойчивости B. rapa ко всем исследованным расам патогена и источники устойчивости к расам Xcc 1 и Xcc 3 среди образцов B. rapa и B. napus....

  13. Maize Cob Rot in Kenya and Its Association with Stalk Borer Damage

    International Nuclear Information System (INIS)

    Cob rots are a major cause of crop loss in areas such as western Kenya that experience prolonged rainfall during the period of crop maturation. Cob rot fungi cause spoilage of the grain and some of them produce mycotoxins which can pose a health risk to humans and animals consuming foods prepared from contaminate grain. survey conducted in western Kenya in 1998 showed that cob rot incidence exceeded 20%. In the following year when rainfall was greater around the harvest period, cob rot fungi affected 68% of cobs. in 1998 stalk borer larvae (mainly Busseola fusca) damaged 20% of the cobs and there was a strong correlation (R= 0.87) between cob rot incidence and borer damage. In 1999 almost half of the cobs sampled showed evidence of borer damage. The result indicate that the high cob rot incidence in this pert of Kenya is due to stalk bore damage, which predisposes the cobs to fungal infection, and that management of the borer would greatly decrease cob rot incidence

  14. Incidência de podridões do colmo, grãos ardidos e rendimento de grãos em híbridos de milho submetidos ao aumento na densidade de plantas Incidence of stalk rot, rot grains and grain yield of maize hybrids submitted to the increase in plant density

    Directory of Open Access Journals (Sweden)

    Ricardo Trezzi Casa

    2007-12-01

    contrasting tolerance to crowding. The experiment was carried out in Lages-SC, during the crop seasons of 2002/03 and 2003/04, in an area of no-tillage and monoculture, having a mixture of black oat and vetch as the preceding winter crop. The experimental design was a randomized block with split plot arrangement and three replications per treatment. Two hybrids were evaluated in the main plots: Speed (a single-cross hybrid tolerant to crowding and AG 303 (a double-cross hybrid intolerant to crowding. Each hybrid was submitted to five plant densities in the split-plots: 25, 50, 75, 100 and 125 thousand plants per ha. The increase in plant density enhanced linearly the occurrence of stalk rot and rot grains for both hybrids and crop seasons. The fungus Colletotrichum graminicola was detected with great frequency in the stalk rot, regardless of hybrid and crop season, followed by Fusarium graminearum, F. verticillioides and Stenocarpella sp. The predominant fungi in rot grains were F. verticillioides, F. graminearum and Penicillium spp. The grain yield of AG 303 was less responsive to the increment in plant density. No association between the higher grain yield of the single-cross hybrid Speed at dense stands and the lower incidence of stalk rot and rot grains was detected.

  15. Effect of Seed Treatments and Root Pathogens on Seedling Establishment and Yield of Alfalfa, Birdsfoot Trefoil and Sweetclover

    OpenAIRE

    Sheau-Fang Hwang; Heping Wang; Gossen, Bruce D.; George D. Turnbull; Ronald J. Howard; Strelkov, Stephen E.

    2006-01-01

    Soil-borne fungal pathogens can reduce stand density in alfalfa (Medicago sativa), birdsfoot trefoil (Lotus corniculatus) and yellow sweetclover (Melilotus officinalis) by reducing seedling establishment and subsequent stand longevity. Fungicide seed treatments containing metalaxyl and fludioxonil were examined in inoculated greenhouse and field tests to determine their efficacy against seedling blight and root rot caused by Fusarium avenaceum and Rhizoctonia solani. Inoculation increased dis...

  16. Control of Ralstonia Solanacearum The Causal Agent of Brown Rot in Potato Using Essential Oils

    International Nuclear Information System (INIS)

    Five essential oils, namely peppermint (Mentha piperita L.), caraway (Carium carvum L.), fennel (Foeniculum vulgare Mill.), lemongrass (Cymbopogon citratus Staph.) and thyme (Thymus vulgaris), were used separately against Ralstonia solanacearum; the causal agent of brown rot in potato. The most two effective oils (peppermint and thyme) were used in vitro and in vivo after testing their effects on potato tubers buds germination. Peppermint inhibited buds germination but thyme have no effects on buds germination. In vivo, the control of brown rot using thyme oil in glass house experiment reduced the percentage of brown rot infection to 30.6% and reduced the severity of disease from 5 to 3.

  17. Distribution and prevalence of crown rot pathogens affecting wheat crops in southern Chile

    OpenAIRE

    Ernesto Moya-Elizondo; Nolberto Arismendi; María Paz Castro; Herman Doussoulin

    2015-01-01

    Crown rot pathogens are associated with higher losses for wheat crop farmers, but information about the distribution and prevalence of these pathogens in Chile is inadequate. Distribution and prevalence of wheat (Triticum aestivum L.) crown rot pathogens were examined in a survey of 48 commercial fields from December 2011 to February 2012 in southern Chile. These fields were located between Collipulli (37°56'00" S; 72°26'39" W) and Purranque (40°50'30" S; 73°22'03" W). Severity of crown rot d...

  18. Touchdowns and Honor Societies: Expanding the Focus of Black Male Excellence

    Science.gov (United States)

    Morris, Jerome E.; Adeyemo, Adeoye O.

    2012-01-01

    The athletic/academic paradox for black males is historically rooted in rank-and-file notions of black people primarily as workers rather than thinkers. Policymakers, educators, and administrators should think more deeply about how societal perceptions of black males as "natural" athletes, rather than intelligent students adversely influences how…

  19. Crescimento radicular, extração de nutrientes e produção de grãos de genótipos de milho em diferentes quantidades de palha de aveia-preta em plantio direto Root growth, nutrient extraction and grain yield of corn genotypes under different amounts of black oat crop residues under no-tillage

    Directory of Open Access Journals (Sweden)

    João Carlos de Moraes Sá

    2010-08-01

    Full Text Available A manutenção da palha na superfície do solo atua principalmente na proteção contra o impacto das gotas de chuva, reduzindo a desagregação, o escorrimento superficial, o transporte de sedimentos e, consequentemente, a erosão. Essa proteção pode ter efeitos significativos nos atributos da planta de milho. O objetivo deste trabalho foi avaliar o efeito da quantidade de palha de aveia-preta em plantio direto no crescimento radicular, na extração de nutrientes e na produção de grãos de genótipos de milho. O experimento foi conduzido em um Latossolo Vermelho distrófico típico, em delineamento experimental de blocos ao acaso em parcelas subdivididas, com três repetições. A parcela principal foi representada pela quantidade de palha na superfície do solo (0, sem palha; 5,0; e 10,0 Mg ha-1, e a subparcela, constituída por 13 genótipos de milho. A quantidade de palha alterou significativamente o comprimento radicular e a altura de requeima. Todavia, a interação entre palha e genótipo alterou significativamente as variáveis estudadas. O sistema radicular das plantas de milho foi beneficiado por doses adicionais de palha tanto na camada superficial (0-20 cm como na subsuperficial (50-100 cm do solo. O aumento na quantidade de palha na superfície do solo resultou na maior extração total de N, P e K e não alterou a extração total dos elementos Ca, Mg e S pela planta de milho.Crop residues on the soil surface act mainly as protection against raindrop impact, reducing aggregate disruption, runoff, sediment transport and consequently, erosion. This protection can have significant effects on the corn plant characteristics. The objective of this study was to evaluate the effect of the amount of black oat residues on no-tillage root development, nutrient uptake and grain yield of corn genotypes. The experiment was conducted in an Oxisol, in a randomized block design in split plots with three replications. The main plot was

  20. Development of sugarcane mutants with resistance to red rot, water-logging and delayed or non-flowering through induced mutations

    International Nuclear Information System (INIS)

    Three varieties of sugarcane, 'Isd-2/54', 'Nagarbari' and 'Latarijaba', were irradiated with 20, 30 and 40 Gy gamma rays to induce variation for resistance to red rot disease. The MV2 population was screened for disease resistance by planting infected canes in between the treated material, and selected plants were further propagated. Among the 2,954 MV3 hills, inoculated with red rot spore suspension, 37 resistant and 151 moderately resistant plants were isolated. Selection was carried out in the MV4 to MV7 propagation. Seven MV7 selected variants were tested for yield at two locations. Of these, four promising variants were selected on the basis of cane yield, Brix index and disease resistance. In another experiment, four varieties of sugarcane, 'Isd-2/54', 'Isd-16', 'Nagarbari' and 'Latarijaba' were irradiated with 20,40 and 60 Gy gamma rays. Approximately, 10,000 MV3 canes were planted in a low-lying field, and subjected to water-logging stress. MV5 and MV6 populations were inoculated with red rot spore- suspension under waterlogged conditions. Five MV5 variants were selected on the basis of greenness of the leaves, growth of the canes, number of nodes bearing adventitious roots, Brix index, cane yield and disease reactions, and grown as MV6 propagation. Three selected variants, SCM-12, SCM-14 and SCM-15, were tolerant to waterlogged conditions in MV6. Two additional varieties, 'I-291/87' and 'I-525/85' were treated with 20, 30 and 40 Gy gamma rays to select for delayed/non-flowering types. Four variants were selected in MV3 for delayed flowering; one mutant, SCM-28 flowered three months later than the parent 'I-291/87'. (author)

  1. Engineering photonic Floquet Hamiltonians through Fabry-Pérot resonators

    Science.gov (United States)

    Sommer, Ariel; Simon, Jonathan

    2016-03-01

    In this paper we analyze an optical Fabry-Pérot resonator as a time-periodic driving of the (2D) optical field repeatedly traversing the resonator, uncovering that resonator twist produces a synthetic magnetic field applied to the light within the resonator, while mirror aberrations produce relativistic dynamics, anharmonic trapping and spacetime curvature. We develop a Floquet formalism to compute the effective Hamiltonian for the 2D field, generalizing the idea that the intra-cavity optical field corresponds to an ensemble of non-interacting, massive, harmonically trapped particles. This work illuminates the extraordinary potential of optical resonators for exploring the physics of quantum fluids in gauge fields and exotic space-times.

  2. Using Square Roots

    Science.gov (United States)

    Wilson, William Wynne

    1976-01-01

    This article describes techniques which enable the user of a comparatively simple calculator to perform calculations of cube roots, nth roots, trigonometric, and inverse trigonometric functions, logarithms, and exponentials. (DT)

  3. A new method to provide resistance to bacterial soft rot in plants

    OpenAIRE

    Bouwmeester, K.; Govers, F.

    2014-01-01

    The invention relates to a method for providing plants, preferably potato plants, with resistance to blackleg or soft rot caused by Pectobacterium carotovorum by providing them with a gene encoding the LecRK-I.9 protein.

  4. Biodegradation of hazardous waste using white rot fungus: Project planning and concept development document

    International Nuclear Information System (INIS)

    The white rot fungus Phanerochaete chrysosporium has been shown to effectively degrade pollutants such as trichlorophenol, polychlorinated biphenyls (PCBs), dioxins and other halogenated aromatic compounds. These refractory organic compounds and many others have been identified in the tank waste, groundwater and soil of various US Department of Energy (DOE) sites. The treatment of these refractory organic compounds has been identified as a high priority for DOE's Research, Development, Demonstration, Testing, and Evaluation (RDDT ampersand E) waste treatment programs. Unlike many bacteria, the white rot fungus P. chrysosporium is capable of degrading these types of refractory organics and may be valuable for the treatment of wastes containing multiple pollutants. The objectives of this project are to identify DOE waste problems amenable to white rot fungus treatment and to develop and demonstrate white rot fungus treatment process for these hazardous organic compounds. 32 refs., 6 figs., 7 tabs

  5. CHARACTERIZATION OF WOOD DECAY BY ROT FUNGI USING COLORIMETRY AND INFRARED SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Mírian de Almeida Costa

    2011-09-01

    Full Text Available Wood samples of marupá (Simarouba amara and andiroba (Carapa guianenis were submitted to Trametes versicolor (white rot and Gloeophylum trabeum (brown rot fungi attack. Colorimetry was used to determine the color of the wood before and after wood decaying fungi. To evaluate the changes in chemical compounds levels in the wood samples, the diffuse reflectance medium infrared spectroscopy was used. Both wood were non resistant against white rot fungus, while with brown rot attack andiroba was resistant and marupá was not. After Gloeophyllum trabeum attack both woods changed to a darken color, and after Trametes versicolor attack andiroba changed to a lighter color and marupá darkened slightly, The analysis showed a reduction in the peak intensity of cellulose, hemicellulose and lignin, for both species, after Trametes versicolor attack and a reduction in the peak intensity of cellulose after Gloeophyllum trabeum attack.

  6. Ultrastructural changes of compressed lumbar ventral nerve roots following decompression

    International Nuclear Information System (INIS)

    To study whether there will be permanent lumbar nerve rot scanning or degeneration secondary to continuous compression followed by decompression on the nerve roots, which can account for postlaminectomy leg weakness or back pain. The study was performed at the Department of Anatomy, Faulty of Medicine, king Abdulaziz University, Jeddah, Kingdom of Saudi Arabia during 2003-2005. Twenty-six adult male New Zealand rabbits were used in the present study. The ventral roots of the left fourth lumbar nerve were clamped for 2 weeks then decompression was allowed by removal of the clips. The left ventral roots of the fourth lumbar nerve were excised for electron microscopic study. One week after nerve root decompression, the ventral root peripheral to the site of compression showed signs of Wallerian degeneration together with signs of regeneration. Schwann cells and myelinated nerve fibers showed severe degenerative changes. Two weeks after decompression, the endoneurium of the ventral root showed extensive edema with an increase in the regenerating myelinated and unmyentilated nerve fibers, and fibroblasts proliferation. Three weeks after decompression, the endoneurium showed an increase in the regenerating myelinated and unmyelinated nerve fibers with diminution of the endoneurial edema, and number of macrophages and an increase in collagen fibrils. Five and 6 weeks after decompression, the endoneurium showed marked diminution of the edema, macrophages, mast cells and fibroblasts. The enoneurium was filed of myelinated and unmyelinated nerve fibers and collagen fibrils. Decompression of the compressed roots of a spinal nerve is followed by regeneration of the nerve fibers and nerve and nerve recovery without endoneurial scarring. (author)

  7. Fischer Black

    OpenAIRE

    Robert C. Merton; Myron S. Scholes

    2013-01-01

    ReprintThis article was originally published by Wiley for the American Finance Association (Merton RC, Scholes MS. 1995. Fischer Black. J. Finance 50(5):1359–70). It is reprinted with permission from John Wiley and Sons © 1995. Reference formatting was updated to facilitate linking.

  8. WHY ROOTING FAILS.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ,M.

    2007-07-30

    I explore the origins of the unphysical predictions from rooted staggered fermion algorithms. Before rooting, the exact chiral symmetry of staggered fermions is a flavored symmetry among the four 'tastes.' The rooting procedure averages over tastes of different chiralities. This averaging forbids the appearance of the correct 't Hooft vertex for the target theory.

  9. Root canal irrigation

    NARCIS (Netherlands)

    L. van der Sluis; C. Boutsioukis; L.M. Jiang; R. Macedo; B. Verhaagen; M. Versluis

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  10. The Root Canal Biofilm

    NARCIS (Netherlands)

    Sluis, van der L.W.M.; Boutsioukis, C.; Jiang, L.M.; Macedo, R.; Verhaagen, B.; Versluis, M.; Chávez de Paz, E.; Sedgley, C.M.; Kishen, A.

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  11. Hendersonia Creberrima, the cause of soft brown rot of mango in South Africa

    International Nuclear Information System (INIS)

    A soft brown rot of mangoes in South Africa, is especially severe in export fruit kept in cold storage for prolonged periods. At present mangoes can be exported most economically by sea. This involves storage at 110C for approximately 21 days. Unfortunately, these appear to be ideal conditions for the development of soft brown rot. Losses as high as 80% were recorded. The South African fungus agrees in morphology and cultural characters with Hendersonia Creberrima

  12. Prospects for Inhibition of lignin degrading enzymes to control ganoderma white rot of oil palm

    OpenAIRE

    Paterson, R. R. M.; Meon, Sariah; Abidin, M. A. Zainal; Lima, Nelson

    2008-01-01

    Oil palm (OP) is prone to a rot by the fungus Ganoderma which may be capable of being controlled by enzyme inhibitors. Palm oil is used in the production of vegetable oil for foods, cosmetics, pharmaceuticals and, most recently, biodiesel. However, the fundamental process of the disease as “white rot” has been ignored by researchers. White rot fungi are capable of degrading lignin ultimately to carbon dioxide and water: Celluloses become available as nutrients for the fungus. One potential co...

  13. Pectobacterium carotovorum subsp. carotovorum – the causal agent of broccoli soft rot in Serbia

    OpenAIRE

    Katarina Gašić; Veljko Gavrilović; Nenad Dolovac; Nenad Trkulja; Svetlana Živković; Danijela Ristić; Aleksa Obradović

    2014-01-01

    Soft rot symptoms were observed on broccoli plants in several commercial fields in the western part of Serbia. Six strains of bacteria were isolated from diseased tissues and identified as Pectobacterium carotovorum subsp. carotovorum using conventional bacteriological and molecular methods. All strains were non-fluorescent, gram-negative, facultative anaerobes, oxidase-negative and catalase-positive, causing soft rot on potato and carrot slices and did not...

  14. The role of secretion systems and small molecules in soft-rot enterobacteriaceae pathogenicity

    OpenAIRE

    Charkowski, Amy; Blanco, Carlos; Condemine, Guy; Expert, Dominique; Franza, Thierry; Hayes, Christopher; Hugouvieux-Cotte-Pattat, Nicole; Lopez Solanilla, Emilia; Low, David; Moleleki, Lucy; Pirhonen, Minna; Pitman, Andrew; Perna, Nicole; Reverchon, Sylvie; Rodriguez Palenzuela, Pablo

    2012-01-01

    Soft-rot Enterobacteriaceae (SRE), which belong to the genera Pectobacterium and Dickeya, consist mainly of broad host-range pathogens that cause wilt, rot, and blackleg diseases on a wide range of plants. They are found in plants, insects, soil, and water in agricultural regions worldwide. SRE encode all six known protein secretion systems present in gram-negative bacteria, and these systems are involved in attacking host plants and competing bacteria. They also produce and detect multiple t...

  15. Interrelationship of the soft rot phytopathogens in the Pectobacterium genus and Caenorhabditis elegans

    OpenAIRE

    Fang, Xin

    2012-01-01

    Bacterial soft rot is one of the most serious diseases affecting potatoes in fields and storages worldwide. Soft rot on potatoes and other crops are caused mainly by Pectobacterium atrosepticum, Pectobacterium carotovorum and several Dickeya species. The disease spreads via many ways and insects are suggested to be important agents in the epidemiology. Evolutionary and geological evidences suggest soil nematodes play essential roles in ecological processes including nutrients cycling, decompo...

  16. Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

    OpenAIRE

    Rahman, M.M.; M. E. Ali; Khan, A. A.; Akanda, A. M.; Uddin, Md. Kamal; Hashim, U.; Abd Hamid, S. B.

    2012-01-01

    A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacterium Erwinia carotovora subsp. carotovora (Ecc) were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was tested in vitro against the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two iso...

  17. Lettuce genotype resistance to "soft rot" caused by Pectobacterium carotovorum subsp. carotovorum

    OpenAIRE

    Kátia Cilene da Silva Felix; Willams José de Oliveira; Rosa de Lima Ramos Mariano; Elineide Barbosa de Souza

    2014-01-01

    Soft rot, caused by Pectobacterium carotovorum subsp. carotovorum (Pcc), is the main bacterial disease affecting lettuce (Lactuca sativa L.) crops in Brazil and leads to significant yield losses. This study aimed to assess the reaction of lettuce genotypes to soft rot induced by a virulent isolate and the stability of the resistance to three isolates varying in virulence. Using a descriptive ordinal scale ranging from 1 to 9 a classification system was defined: class 1 = resistant (R): severi...

  18. Zwalczanie zgnilizny powodowanej przez grzyby z rodzaju Penicillium [Control of Penicillium apple rot

    Directory of Open Access Journals (Sweden)

    H. Borecka

    2015-06-01

    Full Text Available Control of Pezicula spp. fungi reduced Penicillium apple rot. The Penicillium apple rot process began slowly under the modified atmosphere of 5% CO2 and 3% O2. The lower concentration of Benlate – 0.05% did not influence this fungicide's effectiveness, The lower concentration– 0.05% of Topsin M decreased the effectiveness of this fungicide. The resistant strains of Penicillium spp. to benzimidazole fungicides under laboratory conditions were obtained.

  19. Selection of Yeasts Antagonists as Biocontrol Agent of Mango Fruit Rot caused by Botryodiplodia theobromae

    OpenAIRE

    DWI SUGIPRIHATINI; SURYO WIYONO; WIDODO

    2011-01-01

    Fruit rot caused by Botryodiplodia theobromae is one of the most important post harvest disease of mango in Indonesia. Study on biological control on the disease is required to develop environmentally-sound control technology. The research objectives were to study the potency of yeasts in controlling post harvest mango disease i.e. fruit rot caused by B. theobromae and mechanism involve in the biocontrol. Total yeast isolates used for screening were twenty one, four from collection of Plant ...

  20. CONTROL OF POSTHARVEST TOMATO ROT BY SPORE SUSPENSION AND ANTIFUNGAL METABOLITES OF TRICHODERMA HARZIANUM

    OpenAIRE

    El-Katatny, Momein H.; Abeer S. Emam

    2012-01-01

    Rot of cherry tomato (Lycopersicon esculentum) fruits caused by several fungal pathogens is a detrimental disease leading to substantial yield loses worldwide. Alternaria isolates were the most common fungal species isolated from healthy or rotten fruits. Trichoderma harzianum spore suspension and culture filtrate were tested for their antagonistic activity on controlling tomato fruit rot. T. harzianum isolates suppressed or interfered with the growth of different postharvest tomato fungal pa...

  1. Biological Control of Apple Ring Rot on Fruit by Bacillus amyloliquefaciens 9001

    OpenAIRE

    LI Yan; Han, Li-Rong; Zhang, Yuanyuan; Fu, Xuechi; Chen, Xinyi; Zhang, Lixia; Mei, Ruhong; Wang, Qi

    2013-01-01

    Apple ring rot disease, caused by Botryosphaeria dothidea (Moug. ex. Fr) Ces. et de Not., is one of the most important diseases on apple fruits. In this study, strain 9001 isolated from healthy apple fruits from an infested orchard was evaluated for its biocontrol activity against apple ring rot in vitro and in vivo. Strain 9001 showed obvious antagonistic activity to B. dothidea YL-1 when plated on potato dextrose agar. Soaking healthy apples in the bacterial suspensions of strain 9001 prior...

  2. Development stage-dependent susceptibility of cocoa fruit to pod rot caused by Phytophthora megakarya.

    OpenAIRE

    Takam Soh, P.; Ndoumbè-Nkeng, M.; Sache, Ivan; Ndong Nguema, E.P.; Gwet, H.; Chadoeuf, Joel

    2013-01-01

    Pod rot causes up to 30 % losses in world cocoa production. In order to predict the risk evolution of disease, it is important to take into consideration the developmental stage of fruits. In fact, it has been shown that the risk of attack by pod rot depends amongst others on the developmental stage of fruits. We proposed here to estimate the susceptibility at different stages. Susceptibility of fruit to disease was investigated at three fruit developmental stages (cherelle, young pod and adu...

  3. Distribution and prevalence of crown rot pathogens affecting wheat crops in southern Chile

    Directory of Open Access Journals (Sweden)

    Ernesto Moya-Elizondo

    2015-03-01

    Full Text Available Crown rot pathogens are associated with higher losses for wheat crop farmers, but information about the distribution and prevalence of these pathogens in Chile is inadequate. Distribution and prevalence of wheat (Triticum aestivum L. crown rot pathogens were examined in a survey of 48 commercial fields from December 2011 to February 2012 in southern Chile. These fields were located between Collipulli (37°56'00" S; 72°26'39" W and Purranque (40°50'30" S; 73°22'03" W. Severity of crown rot disease was determined through visual assessment of the first internode of 20 tillers obtained from each field. Incidence of crown rot pathogens per field was determined by plating the 20 tillers on Petri plates with 20% potato dextrose agar amended with lactic acid (aPDA medium. Resulting fungal colonies from monoxenic culture were identified by morphological or molecular-assisted identification. Severity of crown rot varied between 11.3% and 80% for individual fields. Culture plate analysis showed 72.2% of stems were infected with some fungus. Fusarium avenaceum, F. graminearum, and F. culmorum, pathogens associated with Fusarium crown rot disease were isolated from 13.5% of tillers. Gaeumannomyces graminis, causal agent of take-all disease in cereals, was isolated from 11.1% of culms. Phaeosphaeria sp., an endophyte and possibly a non-pathogenic fungus, was isolated from 13.9% of tillers. Pathogenic fungi such as Rhizoctonia spp. and Microdochium nivale, other saprophyte, and several unidentified non-sporulating fungi were isolated at frequencies lower than 3% of the total. Fusarium crown rot and take-all were the most prevalent and distributed crown rot diseases present in wheat crops in southern Chile.

  4. Sources of genetic resistance in maize to Fusarium stalk rot andtheir variations at molecular level

    OpenAIRE

    QURESHI, SAJJAD HUSSAIN; Qayyum, Abdul; FIERS, WILL

    2015-01-01

    Identifying the resistant genotypes is one of the vital strategies to control Fusarium stalk rot disease in maize. Fifty accessions of maize germplasm were evaluated for resistance to stalk rot caused by Fusarium verticillioides at the Maize and Millet Research Institute, Yousafwala, Pakistan, during the spring and autumn of 2010, and their genetic variations were also studied at the molecular level to avoid environmental effects in the Department of Medicinal Chemistry, University of Minneso...

  5. Evaluation of fungicide programs for management of Botrytis bunch rot of grapes: 2009 field trial

    OpenAIRE

    Janousek, Christopher N; Bay, Ian S.; Herche, Ryan W; Gubler, W D

    2009-01-01

    Botrytis bunch rot is an important grapevine disease in California. Twenty eight fungicide programs were evaluated for control of bunch rot in a field experiment in a Chardonnay (clone 4) vineyard in the Carneros region of Napa Valley, California during 2009. Four fungicide applications were made from bloom to harvest with the final application made just prior to heavy rainfall. Disease was rated three weeks following the final application. Disease developed rapidly during the month of Octobe...

  6. Evaluation of fungicide programs for management of Botrytis bunch rot of grapes: 2010 field trial

    OpenAIRE

    Bay, Ian S.; Eynard, James; Gubler, W D

    2010-01-01

    Bunch rot of grapes is caused by Botrytis cinerea, a fast-growing pathogen infecting numerous crops of commercial value. Bunch rot can potentially lead to a reduction in the yield and quality of table, raisin, and wine grapes, with high economic losses in some locations or years (Flaherty et al. 1992). Botrytis overwinters as sclerotia in mummified berries on the ground or on canes. The disease can first appear as shoot blight following frequent spring rains; flowers can become infected durin...

  7. Losses due to lenticel rot are an increasing concern for Kern County potato growers

    OpenAIRE

    Farrar, Jim; Nunez, Joe; Davis, R. M.

    2009-01-01

    In recent years, lenticel rot of potato tubers, caused by the bacterium Erwinia carotovora subsp. carotovora, has become an economically important postharvest disease for Kern County growers. Disease symptoms are sunken and rotted tissue surrounding tuber lenticels, which develop after harvest and packing. In the field, the bacterium also causes Erwinia early dying, characterized by wilt and progressive necrosis of leaves, eventually resulting in potato plant death. This study confirms Erwini...

  8. Polycyclic aromatic hydrocarbon degradation by the white rot fungus Bjerkandera sp. strain BOS55.

    OpenAIRE

    Kotterman, M.J.J.

    1998-01-01

    Outline of this thesisIn this thesis the conditions for optimal PAH oxidation by the white rot fungus Bjerkandera sp. strain BOS55 were evaluated. In Chapter 2, culture conditions like aeration and cosubstrate concentrations, which influenced the oxidation of the PAH compound anthracene and the ligninolytic indicator dye Poly R-478 by the white rot fungus, were studied. Two parameters were identified as the most important PAH oxidation rate-limiting factors: the hydrogen peroxide production r...

  9. Experimental and Numerical Characterization of a Hybrid Fabry-Pérot Cavity for Temperature Sensing

    Directory of Open Access Journals (Sweden)

    Aitor Lopez-Aldaba

    2015-04-01

    Full Text Available A hybrid Fabry-Pérot cavity sensing head based on a four-bridge microstructured fiber is characterized for temperature sensing. The characterization of this cavity is performed numerically and experimentally in the L-band. The sensing head output signal presents a linear variation with temperature changes, showing a sensitivity of 12.5 pm/°C. Moreover, this Fabry-Pérot cavity exhibits good sensitivity to polarization changes and high stability over time.

  10. Potato brown rot incidence and severity under different management and amendment regimes in different soil types

    OpenAIRE

    Messiha, N.A.S.; Bruggen, van, C.; Diepeningen, van, A.D.; Vos; Termorshuizen, A.J.; Tjou-Tam-Sin, N.N.A.; Janse, J.D.

    2007-01-01

    Ralstonia solanacearum race 3 biovar 2, the causative agent of potato brown rot (bacterial wilt), is an economically important disease in tropical, subtropical and temperate regions of the world. In view of previous reports on suppression of the disease by organic amendments, and the expansion of organic agriculture, it was timely to compare the effects of organic and conventional management and various amendments on brown rot development in different soils (type: sand or clay; origin: Egypt ...

  11. Evaluation of the bioremediation ability of the isolated white rot fungus on the textile effluents

    OpenAIRE

    Indira Priyadarsini* R; V Bhuvaneswari; K. Suresh Kumar

    2012-01-01

    Every one contributes to the environmental pollution by theiractivities either directly or indirectly and it is our moral responsibility to uncover a solution in order to come out of it also. Hence an attempt was made to isolate a white rot fungus with better remediation ability. The white rot fungus was isolated from decay wood sample and identified as Trametes hirsuta by molecular identification methods. The assessment of the bioremediation ability of the isolated organism was done with fou...

  12. Zwalczanie zgnilizny powodowanej przez grzyby z rodzaju Penicillium [Control of Penicillium apple rot

    OpenAIRE

    H. Borecka

    2015-01-01

    Control of Pezicula spp. fungi reduced Penicillium apple rot. The Penicillium apple rot process began slowly under the modified atmosphere of 5% CO2 and 3% O2. The lower concentration of Benlate – 0.05% did not influence this fungicide's effectiveness, The lower concentration– 0.05% of Topsin M decreased the effectiveness of this fungicide. The resistant strains of Penicillium spp. to benzimidazole fungicides under laboratory conditions were obtained.

  13. Optimization of Laccase Production using White Rot Fungi and Agriculture Wastes in Solid State Fermentation

    OpenAIRE

    Hendro Risdianto; Elis Sofianti; Sri Harjati Suhardi; Tjandra Setiadi

    2012-01-01

    Laccase has been produced in a solid state fermentation (SSF) using white rot fungi and various lignocellulosic based substrates. White rot fungi used were Marasmius sp, Trametes hirsuta, Trametes versicolor and Phanerochaete crysosporium. The solid substrates employed in this research were collected from agriculture waste which were empty fruit bunches (EFB), rice straw, corn cob, and rice husk. The objective of this research was to determine the most promising fungus, the best solid substra...

  14. Soft rot decay capabilities and interactions of fungi and bacteria from fumigated utility poles

    International Nuclear Information System (INIS)

    The objectives were to (1) identify microfungi and bacterial associates isolated from fumigated southern pine poles from EPRI project RP 1471-72, (2) study the soft-rot capabilities of predominant fungi, and (3) study interactions among microorganisms in relation to wood decay. Methods for identification followed standard techniques using morphological and physiological criteria. Soft-rot by microfungi alone and with bacteria was determined as weight loss and anatomical examination of wood blocks using light microscopy and limited electron microscopy. Acinetobacter calcoaceticus was the predominant bacterium. Twenty-one species of microfungi were identified including four new species. A book entitled IDENTIFICATION MANUAL FOR FUNGI FROM UTILITY POLES IN THE EASTERN UNITED STATES was published. An improved soft-rot test was devised. Fifty-one of 84 species (60%) of microfungi from poles tested were soft-rot positive; that is much greater than previously reported. Three types of anatomical damage of wood of pine or birch caused by soft-rot fungi were described. Interaction tests showed that, in some cases, there was a strong synergism between bacteria and fungi in causing weight loss, but results were inconsistent. Although soft rot is often most apparent under conditions of very high moisture, intermediate moisture levels appear to be optimal, as with basidiomycete decayers

  15. Multilocus phylogeny reveals an association of agriculturally important Fusarium solani species complex (FSSC) 11, and clinically important FSSC 5 and FSSC 3 + 4 with soybean roots in the north central United States.

    Science.gov (United States)

    Chitrampalam, P; Nelson, B

    2016-02-01

    The Fusarium solani species complex (FSSC) includes important root pathogens of soybean in the United States, but the evolutionary lineages associated with soybean root rot are unknown. A multilocus phylogeny based on 93 isolates from soybean and pea roots from North Dakota and Minnesota revealed that root rot was associated with three known phylogenetic species, FSSC 3 + 4 (=Fusarium falciforme) (3 % of isolates), FSSC 5 (60 %), FSSC 11 (34 %), and one unknown species, FSSC X (2 %). Of these species FSSC 5 and FSSC 3 + 4 are clinically important while FSSC 11 is a plant pathogen. Isolates from FSSC 11 were pathogenic on soybean, dry bean, pea and lentil, and did not grow at 37 °C. However, isolates from FSSC 5 were weakly to non-pathogenic, but grew at 37 °C. Isolates from both FSSC 5 and FSSC 11 were highly resistant to fludioxonil in vitro. This is the first study revealing the pathogenic robustness of FSSC 11 in causing root rot among Fabaceae crops and also the association of clinically important members of the FSSC with roots of a widely grown field crop in the United States. PMID:26671414

  16. Efeitos de substratos e recipientes utilizados na produção das mudas sobre a arquitetura do sistema radicular de árvores de cácia-negra Effect of nursery substrata and containers on root system architecture of black wattles trees

    Directory of Open Access Journals (Sweden)

    Carmen Silvia Vieira Janeiro Neves

    2005-12-01

    Full Text Available O objetivo deste trabalho foi caracterizar a arquitetura do sistema radicular de árvores de acácia-negra (Acacia mearnsii aos três anos após o plantio, em razão da combinação de oito tipos de recipientes e seis misturas de substratos usados na produção das mudas, levando-se em consideração atributos químicos e físicos do solo. As árvores foram plantadas no município de Cristal (RS, em solo Podzólico Vermelho Escuro, que apresentou alta densidade, baixo pH e excesso de alumínio. O tratamento que teve maior desenvolvimento radicular foi o fertil-pot, com substrato constituído por solo adubado, que diferiu estatisticamente dos tratamentos tubete redondo, com solo adubado + casca de acácia esgotada + vermiculita; paper pot, com solo adubado e laminado acondicionado em caixas de madeira, com solo adubado. O desenvolvimento e arquitetura das raízes no campo foram afetado pelo recipiente, mas não pelo substrato utilizado na fase de viveiro.The objective of this study was to characterize the architecture of the root system of black wattle trees (Acacia mearnsii, three years after planting, in relation to eight types of containers and six substrata used in the nursery, considering chemical and physical conditions of the soil. The experiment was carried out in Cristal (RS, in a Podzolic Dark Red soil. The soil presented high density, low pH and excess of aluminum. The treatment that induced larger root development was fertil-pot with fertilized soil, which differed significantly from the treatments round plug, with fertilized soil + acacia exhausted bark + vermiculite; paper pot, with fertilized soil and laminated in wood box, with fertilized soil. The development and the architecture of the roots in the field was affected by the container but not by the substrata used in the nursery.

  17. Effect of Population Dynamics of Pseudomonas cepacia and Paecilomyces lilacinus on Colonization of Polyfoam Rooting Cubes by Rhizoctonia solani

    OpenAIRE

    Cartwright, D. Kelly; Benson, D. M.

    1994-01-01

    Suspensions of Pseudomonas cepacia (strain 5.5B) and Paecilomyces lilacinus (isolate 6.2F) were applied to polyfoam rooting cubes for control of stem rot of poinsettia caused by Rhizoctonia solani. The populations of antagonists and colonization of rooting cubes by R. solani were monitored during a 3-week period. Colonization of cubes by R. solani was reduced in cubes treated with P. cepacia, but the population of P. cepacia decreased by as much as 97% during the test period. Increased coloni...

  18. Gamma irradiation induced mutation for the improvement of Josapine pineapple against bacterial heart rot disease and improved fruit quality

    International Nuclear Information System (INIS)

    Bacteria heart rot disease, caused by Erwinia chrysanthemi, is one of the most serious diseases of the susceptible cultivars of pineapple in Malaysia, namely, Josapine, Sarawak, Gandul and N36. Using acute irradiation of gamma-rays and in vitro cultured meristems, the selection of resistant mutant to bacterial heart rot disease with improved fruit quality has been carried out using radiation-induced mutagenesis of the most popular variety, Josapine. Meristem explants were irradiated with a series of gamma-ray doses of 0, 20, 40, 60, 80, 100, 120, 140 and 160Gy and radiosensitivity was investigated based on shoot formation and survival rate. The lethal dose required for 50% (LD50) and 100% (LD100) of meristem tissues for shoot formation was 40Gy and 83Gy respectively. On the other hand, the lethal dose required for 50% (LD50) and 100% (LD100) for survival rate was 77Gy and 147Gy respectively. Shoots derived from irradiated meristem explants at 10, 20, 30 and 40Gy were sub-cultured up to M1V5 to minimize chimerism. Multiplication of irradiated shoots was carried out in Temporary Immersion Bioreactor System using MS liquid media supplemented with 2.5mg/l benzyl aminopurine (BA). Rooting was promoted on MS media supplemented with 2mg/l indole-3-butyric acid (IBA) and rooted plantlets were hardened in the nursery for 2 months. Preliminary screening of 20,000 irradiated plants in the nursery indicated 60% with smooth leaves, besides vigorous growth. Selected mutant plantlets were field planted in hot spot until fruiting. At lower doses of 10 and 20Gy, there were no potential resistant mutant plants with significant improvement in total sugar content and fruit weight observed. However, at higher doses of 30 and 40Gy, 11 and 5 resistant plants with significant increase in both total sugar content and fruit weight were recorded, respectively. Molecular analysis using AFLP was conducted to identify markers for the selected characters. (author)

  19. Use of plant growth-promoting rhizobacteria (PGPR and soil organic amendments for the management of root diseases complex of uridbean

    Directory of Open Access Journals (Sweden)

    I. A. Siddiqui

    2013-12-01

    Full Text Available Efficacy of two strains of Pseudomonas aeruginosa (Pa-5 and IE-2 and Bacillus subtilis isolate alone or in conjunction with neem cake or Datura fastuosa was tested for the management of three soilbrne root-infecting fungi including Macrophomina phaseolina, Fusarium solani and Rhizoctonia solani and the root-knot nematode, Meloidogyne javanica on uridbean. Biocontrol bacteria used in combination with either neem cake or D.fastuosa gave better control of the root-rot and root-knot infection with the enhancement of growth of uridbean compared to the use ofeither component alone. Neem cake l% w/w mixed with P.aeruginosa strain IE-2 caused greatest inhibition of the root-knot development due to M.javanica, P.aeruginosa and B.subtilis used with organic amendment also increased Bradyrhizobium-nodules in the root system.

  20. Agronomical and molecular factors influencing bananas (Musa acuminata, AAA, cv ‘Grande-Naine’) susceptibility to crown rot disease

    OpenAIRE

    Lassois, Ludivine

    2009-01-01

    Crown rot affects export bananas in all producing countries and is considered to be one of the main export banana post-harvest disease. Variations are observed in the expression of crown rot symptoms. An original approach of the disease is proposed and consists on presenting the fruit quality potential at harvest as a key factor in crown rot development. This potential develops during growth of bananas in the field and depends on a physiological and a parasitical component. The...

  1. Revised Phylogeny and Novel Horizontally Acquired Virulence Determinants of the Model Soft Rot Phytopathogen Pectobacterium wasabiae SCC3193

    OpenAIRE

    Johanna Nykyri; Outi Niemi; Patrik Koskinen; Jussi Nokso-Koivisto; Miia Pasanen; Martin Broberg; Ilja Plyusnin; Petri Törönen; Liisa Holm; Minna Pirhonen; E Tapio Palva

    2012-01-01

    Soft rot disease is economically one of the most devastating bacterial diseases affecting plants worldwide. In this study, we present novel insights into the phylogeny and virulence of the soft rot model Pectobacterium sp. SCC3193, which was isolated from a diseased potato stem in Finland in the early 1980s. Genomic approaches, including proteome and genome comparisons of all sequenced soft rot bacteria, revealed that SCC3193, previously included in the species Pectobacterium carotovorum, can...

  2. The brown rot fungi of fruit crops (Monilinia spp.), with special reference to Monilinia fructigena (Aderh. & Ruhl.) Honey

    OpenAIRE

    Leeuwen, van

    2000-01-01

    The brown rot fungi of fruit crops ( Monilinia spp.) cause blossom blight, twig blight, and fruit rot in rosaceous fruit crops in the temperate regions of the world. Three species are distinguished, of which M. fructicola and M. laxa are predominant in stone fruit culture, whereas M. fructigena is in pome fruits. This thesis deals partly with taxonomy and identification of the brown rot fungi, and with the epidemiology of M. fructigena in pome fruits.M. fructicola is considered as a quarantin...

  3. Greenhouse evaluation of rhizobia as biocontrol agent of root-infecting fungi in okra

    Directory of Open Access Journals (Sweden)

    I. A. Siddiqui

    2013-12-01

    Full Text Available Nine rhizobial strains isolated from the root nodules of Cicer arietinum, Vigna radiata, V. mungo, Samania saman, Sesbania sesban, Leucinia sp., Prosopis cineraria and Medicago sativa were used to study their effects on root-infecting fungi viz., Macrophomina phaseolina, Fusarium solani and Rhizoctonia solani. In dual culture plate assay, strains of Bradyrhizobium sp., and R. meliloti were found to inhibit radial growth of M. phaseolina, F. solani and R. solani producing zones of inhibition. Bradyrhizobium sp., and R. meliloti either used as seed dressing or as soil drench significantly suppressed root-rot infection caused by M. phaseolina, F. solani and R. solani in okra, a non-1eguminous crop under greenhouse conditions. Biomass of plants was also higher in the presence of rhizobia.

  4. Enhanced bioprocessing of lignocellulose: Wood-rot fungal saccharification and fermentation of corn fiber to ethanol

    Science.gov (United States)

    Shrestha, Prachand

    This research aims at developing a biorefinery platform to convert corn-ethanol coproduct, corn fiber, into fermentable sugars at a lower temperature with minimal use of chemicals. White-rot (Phanerochaete chrysosporium), brown-rot (Gloeophyllum trabeum) and soft-rot (Trichoderma reesei) fungi were used in this research to biologically break down cellulosic and hemicellulosic components of corn fiber into fermentable sugars. Laboratory-scale simultaneous saccharification and fermentation (SSF) process proceeded by in-situ cellulolytic enzyme induction enhanced overall enzymatic hydrolysis of hemi/cellulose from corn fiber into simple sugars (mono-, di-, tri-saccharides). The yeast fermentation of hydrolyzate yielded 7.1, 8.6 and 4.1 g ethanol per 100 g corn fiber when saccharified with the white-, brown-, and soft-rot fungi, respectively. The highest corn-to-ethanol yield (8.6 g ethanol/100 g corn fiber) was equivalent to 42 % of the theoretical ethanol yield from starch and cellulose in corn fiber. Cellulase, xylanase and amylase activities of these fungi were also investigated over a week long solid-substrate fermentation of corn fiber. G. trabeum had the highest activities for starch (160 mg glucose/mg protein.min) and on day three of solid-substrate fermentation. P. chrysosporium had the highest activity for xylan (119 mg xylose/mg protein.min) on day five and carboxymethyl cellulose (35 mg glucose/mg protein.min) on day three of solid-substrate fermentation. T. reesei showed the highest activity for Sigma cell 20 (54.8 mg glucose/mg protein.min) on day 5 of solid-substrate fermentation. The effect of different pretreatments on SSF of corn fiber by fungal processes was examined. Corn fiber was treated at 30 °C for 2 h with alkali [2% NaOH (w/w)], alkaline peroxide [2% NaOH (w/w) and 1% H2O 2 (w/w)], and by steaming at 100 °C for 2 h. Mild pretreatment resulted in improved ethanol yields for brown- and soft-rot SSF, while white-rot and Spezyme CP SSFs showed

  5. Grass Roots: African Origins of an American Art

    OpenAIRE

    E. N. Anderson

    2010-01-01

    Review of Grass Roots: African Origins of an American Art. Dale Rosengarten, Theodore Rosengarten, and Enid Schildkrout, eds. 2008. Museum for African Art, New York. Distributed by University of Washington Press, Seattle. Pp. 269, copiously illustrated in black-and-white and color. ISBN (cloth) 978-0-945802-50-1, (paper) 978-0-945802-51-8.

  6. Genetic association among root morphology, root quality and root yield in ashwagandha (Withania somnifera)

    OpenAIRE

    Kumar Ramesh R.; Reddy Anjaneya Prasanna L.; Subbaiah Chinna J.; Kumar Niranjana A.; Prasad Nagendra H.N.; Bhukya Balakishan

    2011-01-01

    Ashwagandha (Withania somnifera) is a dryland medicinal crop and roots are used as valuable drug in traditional systems of medicine. Morphological variants (morphotypes) and the parental populations were evaluated for root - morphometric, quality and yield traits to study genetic association among them. Root morphometric traits (root length, root diameter, number of secondary roots/ plant) and crude fiber content exhibited strong association among them and ...

  7. Gamma Irradiation-Induced Mutation for the Improvement of Josapine Pineapple Against Bacterial Heart Rot Disease and Improved Fruit Quality

    International Nuclear Information System (INIS)

    incubated at 23oC with a 16-hour photoperiod. Rooting of shoots was promoted on MS media with 2 mg/l of Indole-3-butyric acid (IBA). Rooted plantlets measuring 10 to 12.5cm were transplanted to soil-mix in plastic trays for hardening. Mutation of regenerated plants was investigated two months after acclimatization. Preliminary screening of 20,000 irradiated plants in the nursery was first undertaken to select for potential mutants with desired characters, and 60% of the irradiated plants were observed to have smooth leaves and vigorous growth. Hardened irradiated plants with smooth leaves measuring 17.5 to 20cm were field planted in hot spot until fruiting. Potential mutants were selected based on desired characters such as a) resistance to bacterial heart rot disease, b) single crown, c) cylindrical fruit shape with big fruit size and weight, and d) high sugar content. At 10 and 20Gy, there were no potential resistant mutants with a significantly improved total sugar content and fruit weight. However, at higher doses of 30 and 40Gy, 11 and five resistant plants with significant increase in total sugar content and fruit weight were recorded, respectively. (author)

  8. How can we harness quantitative genetic variation in crop root systems for agricultural improvement?

    Science.gov (United States)

    Topp, Christopher N; Bray, Adam L; Ellis, Nathanael A; Liu, Zhengbin

    2016-03-01

    Root systems are a black box obscuring a comprehensive understanding of plant function, from the ecosystem scale down to the individual. In particular, a lack of knowledge about the genetic mechanisms and environmental effects that condition root system growth hinders our ability to develop the next generation of crop plants for improved agricultural productivity and sustainability. We discuss how the methods and metrics we use to quantify root systems can affect our ability to understand them, how we can bridge knowledge gaps and accelerate the derivation of structure-function relationships for roots, and why a detailed mechanistic understanding of root growth and function will be important for future agricultural gains. PMID:26911925

  9. Root canal irrigants

    Directory of Open Access Journals (Sweden)

    Kandaswamy Deivanayagam

    2010-01-01

    Full Text Available Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are discussed. We performed a Medline search for English-language papers published untill July 2010. The keywords used were ′root canal irrigants′ and ′endodontic irrigants.′ The reference lists of each article were manually checked for additional articles of relevance.

  10. FTIR and XPS analysis of the changes in bamboo chemical structure decayed by white-rot and brown-rot fungi

    International Nuclear Information System (INIS)

    In order to investigate different types of decay mechanisms in bamboo (Phyllostachys edulis), the chemical structure and microstructure of bamboo samples decayed by P. chrysosporium (White-rot) and G. trabeum (Brown-rot) for 12 weeks were studied. The analysis methods include fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron spectroscopy (SEM). By using the SEM method, it was found that attacks to parenchyma cells and places near the inner skin of bamboo were the most frequent and the vessels were the primary paths for the spread of mycelium in the bamboo. FTIR and XPS results showed that the crystallinity (I1425/I896) of bamboo decreased after being decayed by these two fungi and the crystalline cellulose in bamboo was degraded. The white-rot P. chrysosporium had stronger degradability on lignin compared to hemicellulose and cellulose in bamboo. And the brown-rot G. trabeum had preferential degradability on hemicellulose fraction over cellulose and lignin. Oxidation and hydrolysis surface reactions occurred during the process of decay, but the reaction rates for cellulose and lignin were different.

  11. FTIR and XPS analysis of the changes in bamboo chemical structure decayed by white-rot and brown-rot fungi

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Guoqi [College of Engineering and Technology, Northeast Forestry University, Harbin 150040 (China); Wang, Lihai, E-mail: xu12nefu@sina.cn [College of Engineering and Technology, Northeast Forestry University, Harbin 150040 (China); Liu, Junliang [Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091 (China); Wu, Jinzhuo [College of Engineering and Technology, Northeast Forestry University, Harbin 150040 (China)

    2013-09-01

    In order to investigate different types of decay mechanisms in bamboo (Phyllostachys edulis), the chemical structure and microstructure of bamboo samples decayed by P. chrysosporium (White-rot) and G. trabeum (Brown-rot) for 12 weeks were studied. The analysis methods include fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron spectroscopy (SEM). By using the SEM method, it was found that attacks to parenchyma cells and places near the inner skin of bamboo were the most frequent and the vessels were the primary paths for the spread of mycelium in the bamboo. FTIR and XPS results showed that the crystallinity (I1425/I896) of bamboo decreased after being decayed by these two fungi and the crystalline cellulose in bamboo was degraded. The white-rot P. chrysosporium had stronger degradability on lignin compared to hemicellulose and cellulose in bamboo. And the brown-rot G. trabeum had preferential degradability on hemicellulose fraction over cellulose and lignin. Oxidation and hydrolysis surface reactions occurred during the process of decay, but the reaction rates for cellulose and lignin were different.

  12. Some new and noteworthy diseases of poplars in India. [Botryodiplodia sett-rot; Alternaria tip blight; Cladosporium leaf spot; Fusarium pink incrustation

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.

    1983-09-01

    Four new diseases of poplars namely Botryodiplodia sett-rott, Alternaria tip blight, Cladosporium leaf spot and Fusarium pink incrustation are described in this paper. Botryodiplodia palmarum causes sett-rott of poplars both at pre-sprouting and post-sprouting stage. The pathogen also causes mortality of poplar plants in the field within 4-6 weeks after planting. Alternaria stage of Pleuspora infectoria has been found as the cause of blackening and dying of growing tips and young leaves of a Populus sp. and P. deltoides in nurseries. Cladosporium humile has been recorded as the cause of brown spot followed by crumpling and premature shedding of leaves in P. ciliata, P. nigra and P. alba. The cause of Fusarium incrustation disease on P. cilata has been identified as Fusarium sp. of Gibbosum group. Pathogenicity of Botryodiplodia palmarum and Alternaria stage of Pleospora infectoria was confirmed by artificial inoculations. Brief descriptions of Alternaria, Cladosporium and Fusarium are also given. The paper also gives a short account of some noteworthy diseases recorded on poplars namely Ganoderma root rot, foliage ruts and stem cankers. Ganoderma root-rot is found to reach alarming proportions in closely spaced poplar plantations. Melampsora ciliata, an indigenous rust, is found to attack mainly clones of P. deltoides, P. yunnanensis, P. trichocarpa, P. alba and some cultivars of P. x euramericana in nurseries. A brief account of three types of stem cankers i.e. cankers due to pink disease fungus, Corticium salmonicolor, sun-scaled cankers and cankers associated with slime flux on various clones of P. deltoides is also given.

  13. First report of black-foot disease, caused by Cylindrocarpon destructans, on ornamental marigold (Tagetes minuta) in Iran

    OpenAIRE

    Jamali Samad; Nasimi Zohreh

    2014-01-01

    The ornamental Tagetes minuta is a herbaceous plant of the Asteraceae family. T. minuta, a species native to southern South America, is used as a condiment, as a refreshing beverage, and for medicinal purposes. In 2011, disease symptoms of yellowing, root and foot rot, drying of leaves, and plant death were observed in an ornamental marigold (T. minuta) greenhouse in Fars province. The infected plants were collected and transferred to a laboratory. Samples were washed, cut into small pieces, ...

  14. Incorporation of plant materials in the control of root pathogens in muskmelon

    Directory of Open Access Journals (Sweden)

    Andréa Mirne de Macêdo Dantas

    2013-12-01

    Full Text Available The effect of plant materials[Sunn Hemp (Crotalaria juncea, Castor Bean (Ricinus communis L., Cassava (Manihot esculenta Crantz and Neem (Azadirachta indica] and the times of incorporation of these materials in regards to the incidence of root rot in melon was evaluated in Ceará state, Brazil. The experiment was conducted in a commercial area with a history of root pathogens in cucurbitaceae. The randomized block design was used, in a 5 x 3 factorial arrangement with four repetitions. The treatments consisted of a combination of four plant materials (sunn hemp, castor beans, cassava and neem and a control with no soil incorporation of plant material and three times of incorporation (28, 21, and 14 days before the transplanting of the seedlings. Lower incidence of root rot was observed in practically all of the treatments where materials were incorporated at different times, with variation between the materials, corresponding with the time of incorporation, in relation to the soil without plant material. The pathogens isolated from the symptomatic muskmelon plants were Fusarium solani, Macrophomina phaseolina, Monosporascus cannonballus and Rhizoctonia solani, F. solani being encountered most frequently.

  15. Production of Ligninolytic Enzymes by White-Rot Fungus Datronia sp. KAPI0039 and Their Application for Reactive Dye Removal

    Directory of Open Access Journals (Sweden)

    Pilanee Vaithanomsat

    2010-01-01

    Full Text Available This study focused on decolorization of 2 reactive dyes; Reactive Blue 19 (RBBR and Reactive Black 5 (RB5, by selected white-rot fungus Datronia sp. KAPI0039. The effects of reactive dye concentration, fungal inoculum size as well as pH were studied. Samples were periodically collected for the measurement of color unit, Laccase (Lac, Manganese Peroxidase (MnP, and Lignin Peroxidase (LiP activity. Eighty-six percent of 1,000 mg L−1 RBBR decolorization was achieved by 2% (w/v Datronia sp. KAPI0039 at pH 5. The highest Lac activity (759.81 UL−1 was detected in the optimal condition. For RB5, Datronia sp. KAPI0039 efficiently performed (88.01% decolorization at 2% (w/v fungal inoculum size for the reduction of 600 mg L−1 RB5 under pH 5. The highest Lac activity (178.57 UL−1 was detected, whereas the activity of MnP and LiP was absent during this hour. The result, therefore, indicated that Datronia sp. KAPI0039 was obviously able to breakdown both reactive dyes, and Lac was considered as a major lignin-degradation enzyme in this reaction.

  16. Roots and routes

    DEFF Research Database (Denmark)

    Christensen, Ann-Dorte; Jensen, Sune Qvotrup

    2011-01-01

    arguing that there is a dynamic interplay between roots and routes in people's lives. The empirical point of departure is narratives about roots and routes by ethnic minorities settled in Aalborg East, an underprivileged neighbourhood in northern Denmark. One of the main findings is a gap between the...... somewhat paradoxical finding is that it appears to be more difficult for transnational migrants to maintain their roots in the country of origin when they go back than it was to establish new roots in the host country...

  17. Roots of Dehn twists

    OpenAIRE

    McCullough, Darryl; Rajeevsarathy, Kashyap

    2009-01-01

    D. Margalit and S. Schleimer found examples of roots of the Dehn twist about a nonseparating curve in a closed orientable surface, that is, homeomorphisms whose nth power is isotopic to the Dehn twist. Our main theorem gives elementary number-theoretic conditions that describe the values of n for which an nth root exists, given the genus of the surface. Among its applications, we show that n must be odd, that the Margalit-Schleimer roots achieve the maximum value of n among the roots for a gi...

  18. Developmental and Metabolic Plasticity of White-Skinned Grape Berries in Response to Botrytis cinerea during Noble Rot.

    Science.gov (United States)

    Blanco-Ulate, Barbara; Amrine, Katherine C H; Collins, Thomas S; Rivero, Rosa M; Vicente, Ariel R; Morales-Cruz, Abraham; Doyle, Carolyn L; Ye, Zirou; Allen, Greg; Heymann, Hildegarde; Ebeler, Susan E; Cantu, Dario

    2015-12-01

    Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines. PMID:26450706

  19. Developmental and Metabolic Plasticity of White-Skinned Grape Berries in Response to Botrytis cinerea during Noble Rot1[OPEN

    Science.gov (United States)

    Collins, Thomas S.; Vicente, Ariel R.; Doyle, Carolyn L.; Ye, Zirou; Allen, Greg; Heymann, Hildegarde

    2015-01-01

    Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines. PMID:26450706

  20. Draft Genome Sequences of Dickeya sp. Isolates B16 (NIB Z 2098) and S1 (NIB Z 2099) Causing Soft Rot of Phalaenopsis Orchids.

    Science.gov (United States)

    Alič, Špela; Naglič, Tina; Llop, Pablo; Toplak, Nataša; Koren, Simon; Ravnikar, Maja; Dreo, Tanja

    2015-01-01

    The genus Dickeya contains bacteria causing soft rot of economically important crops and ornamental plants. Here, we report the draft genome sequences of two Dickeya sp. isolates from rotted leaves of Phalaenopsis orchids. PMID:26358590

  1. Draft Genome Sequences of Dickeya sp. Isolates B16 (NIB Z 2098) and S1 (NIB Z 2099) Causing Soft Rot of Phalaenopsis Orchids

    OpenAIRE

    Alič, Špela; Naglič, Tina; Llop, Pablo; Toplak, Nataša; Koren, Simon; Ravnikar, Maja; Dreo, Tanja

    2015-01-01

    The genus Dickeya contains bacteria causing soft rot of economically important crops and ornamental plants. Here, we report the draft genome sequences of two Dickeya sp. isolates from rotted leaves of Phalaenopsis orchids.

  2. Diversity of symbiotic root endophytes of the Helotiales in ericaceous plants and the grass, Deschampsia flexuosa

    OpenAIRE

    Zijlstra, J.D.; Hof, van 't, G.; Baar, J.; Verkley, G.J.M.; Summerbell, R.C; Paradi, I.; Braakhekke, W.G.; Berendse, F.

    2005-01-01

    In a study of fungi growing in various root-associated habitats in and around Picea mariana, black spruce, in northern Ontario, Canada, an examination was made of the degree to which differences in growth sites within an area of a few square kilometers might influence the structure of root-associated filamentous microfungal populations. Picea mariana roots were collected at four strongly differing boreal forest sites: an undisturbed forest site with deep litter and humus layers; a recently re...

  3. Environmental Impact of Using Phlebiopsis gigantea in Stump Treatment Against Heterobasidion annosum sensu lato and Screening Root Endophytes to Identify Other Novel Control Agents

    OpenAIRE

    Terhonen, Eeva-Liisa

    2015-01-01

    Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) cover large areas in boreal regions with significant economic importance to Finnish forest industry. Approximately 15% of the spruce trees felled in Finland are rotten and thus commercially less valuable. The majority of this conifer wood decay is due to the root and butt rot pathogen Heterobasidion annosum sensu lato. Extensive logging of conifer forests has changed the environment into favouring this pathogen in stands where it o...

  4. Impact of cover crop in pre-plant of apple orchards: relationship between crop health, root inhabiting fungi and rhizospheric bacteria

    OpenAIRE

    Manici, L.; Kelderer, M; Caputo, F.; F. Nicoletti; De Luca Picione , F.; Topp , A.R

    2015-01-01

    Manici, L. M., Kelderer, M., Caputo, F., Nicoletti, F., De Luca Picione, F. and Topp A. R. 2015. Replant disease of fruit tree orchards has a multifactorial etiology, mainly due to the decline in soil biodiversity along with an increase in root rot pathogens, which can be principally countered with appropriate cropping practices. Therefore, a study on the impact of cover crops on plant health of young fruit trees in long-term orchards was performed. Bioassays were performed over two conse...

  5. Comparing lignocellulose physiochemistry after decomposition by brown rot fungi with distinct evolutionary origins.

    Science.gov (United States)

    Kaffenberger, Justin T; Schilling, Jonathan S

    2015-12-01

    Among wood-degrading fungi, lineages holding taxa that selectively metabolize carbohydrates without significant lignin removal (brown rot) are polyphyletic, having evolved multiple times from lignin-removing white rot fungi. Given the qualitative nature of the 'brown rot' classifier, we aimed to quantify and compare the temporal sequence of carbohydrate removal among brown rot clades. Lignocellulose deconstruction was compared among fungi using distinct plant substrates (angiosperm, conifer, grass). Specifically, aspen, pine and corn stalk were harvested over a 16-week time series from microcosms containing Gloeophyllum trabeum, Fomitopsis pinicola, Ossicaulis lignatilis, Fistulina hepatica, Serpula lacrymans, Wolfiporia cocos or Dacryopinax sp. After quantifying plant mass loss, a thorough compositional analysis was complemented by a saccharification test to determine wood cell wall accessibility. Mass loss and accessibility varied depending on fungal decomposer and substrate, and trajectories of loss for hemicellulosic components and cellulose differed among plant tissue types. At any given stage of decomposition, however, lignocellulose accessibility and the fraction remaining of carbohydrates and lignin within a plant tissue type were generally the same, regardless of fungal isolate. This suggests that the sequence of plant component removal at this typical scale of characterization is shared among these brown rot lineages, despite their diverse genomes and secretomes. PMID:25181619

  6. Pre-breeding in sugarcane (Saccharum sp. hybrids for red rot resistance and economic traits

    Directory of Open Access Journals (Sweden)

    C. Babu

    2010-07-01

    Full Text Available The present investigation is concerned with the development of genetic stocks for resistance to red rot disease caused byColletotrichum falcatum Went and other important economic traits. This was studied with progenies obtained from 39crosses involving 45 parental clones of interspecific and intervarietal origin. The progenies were subjected for screeningagainst red rot under controlled condition testing (CCT method. The pattern of inheritance of red rot resistance showedin general that, crosses involving resistant parents tend to have more number of resistant progenies than from crosses involvingsusceptible parents. Out of 39 crosses investigated for race specific resistance as a qualitative trait, 18 crosses showed a simpleMendelian segregation of monogenic nature. Parent progeny regression analysis suggested that about 50% of thevariation in the population could be attributed to additive genetic variance (horizontal resistance. Two crosses involvingsusceptible parents viz., 971235 (S x Co 1148 (S and Co 88028 (S x Co 775 (S contributed 28-30% resistantprogenies. These transgressive segregants are likely to be stable in their resistance due to additive genetic action andcould be used as donor parents in red rot resistance breeding programmes for imparting race non-specific resistance. Thepresent investigation has also identified some specific cross combinations for yield, quality and red rot resistance forfurther exploitation in breeding programme.

  7. Involvement of phenolic compounds in the susceptibility of bananas to crown rot. A review

    Directory of Open Access Journals (Sweden)

    Lassois, L.

    2012-01-01

    Full Text Available Crown rot of bananas, caused by a fungal parasitic complex, is one of the main quality defects of exported bananas. Major variations in the susceptibility of bananas to crown rot have been observed in different production zones. The physiological state of the banana fruit at harvest is said to influence its response to pathogenic attack and thus to modulate its susceptibility to crown rot. The susceptibility of bananas to this disease, however, appears to be influenced by many pre-harvest factors, although the underlying defense mechanisms have not been clearly identified. A recent report based on molecular analyses suggests that phenolic compounds might be involved in the different variations in the susceptibility of bananas to crown rot. Results of other earlier studies point to an involvement of phenolic compounds in the defensive reactions of banana plants against various pathogens. The present paper reviews the current state of knowledge on the variations in the susceptibility of bananas to crown rot and takes stock of what is known about phenolic compounds in relation to their potential involvement in the defense mechanisms of the banana plant.

  8. Behavior of hybrid corn crop as second rot incidence in West Region Paraná

    Directory of Open Access Journals (Sweden)

    Jean Sérgio Rosset

    2013-09-01

    Full Text Available The objective of this study was to evaluate the incidence and influence of stalk rot and ear in cultivation of hybrid corn second crop in west region Paraná. The experiment was conducted in randomized block design with six transgenic corn hybrids (DKB 330PRO, P4285HX, P3646HX, 30F53HX, P3340HX and P3161HX with four replications at spacing of 0.90 m between rows and 0.20 m between plants. The characteristics evaluated were: number of healthy and symptomatic plants, number of ears healthy and symptomatic and total number of spikes. After harvest, we assessed the length of ears healthy and symptomatic, bulk grain ears healthy and symptomatic, thousand grain weight of ears healthy and symptomatic, and grain mass per spike weighted, thousand grain weight and weighted productivity. The hybrid P3646HX showed 100% of plants with stem base rot (Colletotrichum graminicola and soft rot cob (Erwinia chrysanthemi pv. Zeae and 100% of ears with symptoms of soft rot, followed by hybrid 30F53HX, DKB 330PRO with 34.9 and 29.1% of ears with symptoms of soft rot respectively. The hybrid DKB330PRO showed healthy spikes and patients with superior size, resulting in less interference in the grain yield. The hybrid P3340 productivity was higher, with 7952 kg ha-1 , followed by hybrid 30F53HX and DKB330PRO. A positive correlation between agronomic characteristics and grain yield.

  9. Radionic nonuniform black strings

    Science.gov (United States)

    Tamaki, Takashi; Kanno, Sugumi; Soda, Jiro

    2004-01-01

    Nonuniform black strings in the two-brane system are investigated using the effective action approach. It is shown that the radion acts as a nontrivial hair of the black strings. From the brane point of view, the black string appears as the deformed dilatonic black hole which becomes a dilatonic black hole in the single brane limit and reduces to the Reissner-Nordström black hole in the close limit of two-branes. The stability of solutions is demonstrated using catastrophe theory. From the bulk point of view, the black strings are proved to be nonuniform. Nevertheless, the zeroth law of black hole thermodynamics still holds.

  10. Interactions between cranberries and fungi: the proposed function of organic acids in virulence suppression of fruit rot fungi

    Science.gov (United States)

    Cranberry fruit are a rich source of bioactive compounds that may function as constitutive or inducible barriers against rot-inducing fungi. The content and composition of these compounds change as the season progresses. Several necrotrophic fungi cause cranberry fruit rot disease complex. These fun...

  11. PCR assays for diagnosis of postharvest fruit rots and early detection of Phacidiopycnis washingtonensis and Sphaeropsis pyriputrescens in apple fruit

    Science.gov (United States)

    Speck rot caused by Phacidiopycnis washingtonensis and Sphaeropsis rot caused by Sphaeropsis pyriputrescens are two recently reported postharvest diseases of apple. Fruit infection by the pathogens occurs in the orchard, but symptoms develop after harvest and are similar to that of gray mold caused...

  12. First report of Lasiodiplodia theobromae causing inflorescence blight and fruit rot of longan (Dimocarpus longan L.) in Puerto Rico

    Science.gov (United States)

    Longan is a tropical fruit tree in the Sapindaceae family. During a disease survey from 2008 to 2010, fruit rot and inflorescence blight (rotting of the rachis, rachilla and flowers) were observed at the USDA-ARS Research Farm in Isabela, Puerto Rico. Tissue sections (1 mm2) of diseased inflorescenc...

  13. Chitosan and oligochitosan enhance ginger (Zingiber officinale Roscoe) resistance to rhizome rot caused by Fusarium oxysporum in storage

    Science.gov (United States)

    The ability of chitosan and oligochitosan to enhance the resistance of ginger (Zingiber officinale) to rhizome rot, caused by Fusarium oxysporum, in storage was investigated. Both chitosan and oligochitosan at 1 and 5 g/L significantly inhibited rhizome rot, relative to the untreated control, with...

  14. PCR assays for diagnosis of postharvest fruit rots and early detection of Phacidiopycnis washingtonensis and Sphaeropsis pyriputrescens in apple fruit

    Science.gov (United States)

    Speck rot caused by Phacidiopycnis washingtonensis and Sphaeropsis rot caused by Sphaeropsis pyriputrescens are two recently reported postharvest diseases of apple. Infection of fruit by the pathogens occurs in the orchard, but symptoms develop after harvest and are similar to that of gray mold caus...

  15. Use of Pseudomonas aeruginosa in the control od root-knot disease complex in tomato: the effects of different inoculum levels of Meloidogyne javanica and Rhizoctonia solani

    Directory of Open Access Journals (Sweden)

    I. A. Siddiqui

    2013-12-01

    Full Text Available The potential impact of Pseudomons aeruginosa strain IE-6 as a biological control agent against Meloidogyne javanica at four inoculum densities (0, 250, 500 and 1000 eggs/plant and Rhizoctonia solani at three inoeulum levels (0, 1 and 3 ml culture suspension/kg of soil was examined on tomato in the greenhouse experiments. The biocontrol bacterium suppressed root infection caused by R. solani and M. javanica on tomato in both sterilized and non-sterilized soils. Root-rot infection increased with the increase in pathogen(s concentration. P. aeruginosa showed better biocontrol effects at low population levels of M.javanica and R. solani than at higher population densities of the pathogen(s. Root-rot disease severity was more pronounced in sterilized soil compared to the non-sterilized one. Soil infested with high population densities ofR. solani (3 ml /kg of soil and M. javanica (2000 eggs/pot resulted in complete mortality of tomato seedlings in sterilized soil, whereas some plants were found to survive in non-stenlized soil. There seems to be a correlation between population density of M. javanica and root colonization by R. solani. Root colonization by other three root-infecting fungi including Macrophomina phaseolina, Fusarium oxysporum and Fusarium solani was also lower in the presence of P. aeruginosa in non-sterilized soil. P. aeruginosa enhanced plant growth in both types of soil.

  16. Chromatic roots and hamiltonian paths

    DEFF Research Database (Denmark)

    Thomassen, Carsten

    2000-01-01

    We present a new connection between colorings and hamiltonian paths: If the chromatic polynomial of a graph has a noninteger root less than or equal to t(n) = 2/3 + 1/3 (3)root (26 + 6 root (33)) + 1/3 (3)root (26 - 6 root (33)) = 1.29559.... then the graph has no hamiltonian path. This result is...

  17. Evaluation of the bioremediation ability of the isolated white rot fungus on the textile effluents

    Directory of Open Access Journals (Sweden)

    Indira Priyadarsini* R

    2012-08-01

    Full Text Available Every one contributes to the environmental pollution by theiractivities either directly or indirectly and it is our moral responsibility to uncover a solution in order to come out of it also. Hence an attempt was made to isolate a white rot fungus with better remediation ability. The white rot fungus was isolated from decay wood sample and identified as Trametes hirsuta by molecular identification methods. The assessment of the bioremediation ability of the isolated organism was done with four textile effluent samples and the physico-chemical parameters namely colour, pH, TSS, TDS, COD, BOD, Total Hardness, level of Calcium, Magnesium, Chloride and Sulphate were evaluated. The change in the initial pH values of the four textile effluents after treatment with the isolated organism was not significant. All the other parameters were found to be reduced from their respective initial level after treatment with the isolated white rot fungus.

  18. ISOLATION AND IDENTIFICATION OF BACTERIAL CAUSED SOFT ROT DISEASE ON CARROT (Daucus carota L. LOCAL VARIETY IN BALI

    Directory of Open Access Journals (Sweden)

    Ni Wayan Desi Bintari

    2015-03-01

    Full Text Available Soft rot bacteria infection in carrot tuber (D. carota L. causes severe economic losses. Soft rot disease can be caused by various bacteria belonging to Enterobacteriaceae. This study aimed to isolate and identify bacteria as causal agent of soft rot disease in local carrot variety in Bali. Samples were collected at Badung Tradisional Market, Denpasar, Bali. Isolation was carried out by serial dilution method (Platting Method. Eight bacteria (BL1, BL2, BL3, BL4, BL5, BL6, BL7 and BL8 were isolated from soft rot tuber. BL6 isolate showed positive result in Postulat Koch test that caused soft rot on carrot tuber. The result of identification by Microgen™ GnA+B-ID System and identification book Bergeys’s Manual of Determinative Bacteriology Ninth Edition (Holt et al., 1994, BL6 was identified as Citrobacter.

  19. Using the Resistograph®to distinguish different types of wood rot on living silver fir in Molise (Italy

    Directory of Open Access Journals (Sweden)

    Lasserre B

    2010-10-01

    Full Text Available he study was performed in two silver-fir forests (Abies alba Mill. located in Alto Molise, Province of Isernia: Collemeluccio, near Pescolanciano and Abeti Soprani near Capracotta. The aim of this work was to distinguish different types of wood rot on living silver fir individuals by using the Resistograph® (IML-RESI E400, a device that allows to estimate the variation of wood density by measuring the resistance to micro-perforation. The occurrence of different types of wood rot (white rot and brown rot in living trees was pointed out and discriminated by the device. In the detected deteriorated zones, fungal pathogens and decomposers were isolated and identified, causing either white (Phellinus hartigii, Ganoderma adspersum, Heterobasidion abietinum and Armillaria ostoyae or brown rot (Fomitopsis pinicola.

  20. [Kinetics model for batch culture of white rot fungus].

    Science.gov (United States)

    Xiong, Xiao-ping; Wen, Xiang-hua; Xu, Kang-ning; Bian, Bing-hui

    2008-02-01

    In order to understand ligninolytic enzymes production process during culture of white rot fungus, accordingly to direct the design of fermentation process, a kinetics model was built for the batch culture of Phanerochaete chrysosporium. The parameters in the model were calibrated based on the experimental data from free and immobilized culture separately. The difference between each variable's values calculated based on kinetics model and experimental data is within 15%. Comparing parameters for the free and the immobilized culture, it is found that maximum biomass concentrations are both 1.78 g/L; growth rate ratio of immobilized culture (0.6683 d(-1)) is larger than that of free culture (0.5144 d(-1)); very little glucose is consumed for biomass growth in free culture while in immobilized culture much glucose is used and ammonium nitrogen is consumed at a greater rate. Ligninolytic enzymes production process is non-growth related; fungal pellets can produce MnP (231 U/L) in free culture with a production rate of 115.8 U x (g x d)(-1) before peak and 26.1 U x (g x d)(-1) after peak, thus fed-batch is a possible mode to improve MnP production and fermentation efficiency. MnP (410 U/L) and LiP (721 U/L) can be produced in immobilized culture, but MnP and LiP production rate decrease from 80.1 U x (g x d)(-1) and 248.9 U x (g x d)(-1) to 6.04 U x (g x d)(-1) and 0 U x (g x d)(-1), respectively, indicating a proper feed moment is before the enzymes peak during fed-batch culture. PMID:18613526

  1. Pathogenicity of and plant immunity to soft rot pectobacteria

    Directory of Open Access Journals (Sweden)

    Pär Roland Davidsson

    2013-06-01

    Full Text Available Soft rot Pectobacteria are broad host range enterobacterial pathogens that cause disease on a variety of plant species including the major crop potato. Pectobacteria are aggressive necrotrophs that harbor a large arsenal of plant cell wall degrading enzymes as their primary virulence determinants. These enzymes together with additional virulence factors are employed to macerate the host tissue and promote host cell death to provide nutrients for the pathogens. In contrast to (hemibiotrophs such as Pseudomonas, type three secretion systems (T3SS and T3 effectors do not appear central to pathogenesis of Pectobacteria. Indeed, recent genomic analysis of several Pectobacterium species including the emerging pathogen Pectobacterium wasabiae has shown that many strains lack the entire T3SS as well as the T3 effectors. Instead, this analysis has indicated the presence of novel virulence determinants. Resistance to broad host range Pectobacteria is complex and does not appear to involve single resistance genes. Instead, activation of plant innate immunity systems including both SA and JA/ET mediated defenses appears to play a central role in attenuation of Pectobacterium virulence. These defenses are triggered by detection of pathogen-associated molecular patterns (PAMPs or recognition of modified-self such as damage-associated molecular patterns (DAMPs and result in enhancement of basal immunity (Pattern-triggered immunity, PTI. In particular plant cell-wall fragments released by the action of the degradative enzymes secreted by Pectobacteria are major players in enhanced immunity towards these pathogens. Most notably bacterial pectin degrading enzymes release oligogalacturonide (OG fragments recognized as DAMPs activating innate immune responses. Recent progress in understanding OG recognition and signaling allows novel genetic screens for OG-insensitive mutants and will provide new insights into plant defense strategies against necrotrophs such as

  2. Toxicity of graphene oxide to white rot fungus Phanerochaete chrysosporium.

    Science.gov (United States)

    Xie, Jingru; Ming, Zhu; Li, Hongliang; Yang, Hua; Yu, Baowei; Wu, Ruihan; Liu, Xiaoyang; Bai, Yitong; Yang, Sheng-Tao

    2016-05-01

    With the wide production and applications of graphene and its derivatives, their toxicity to the environment has received much attention nowadays. In this study, we investigated the toxicity of graphene oxide (GO) to white rot fungus (Phanerochaete chrysosporium). GO was prepared by modified Hummers method and well characterized before use. P. chrysosporium was exposed to GO at the concentrations of 0-4 mg/mL for 7 d. The fresh and dry weights, pH values of culture media, structures, ultrastructures, IR spectra and activities of the decomposition of pollutants were measured to reveal the hazards of GO to P. chrysosporium. Our results indicated that low concentrations of GO stimulated the growth of P. chrysosporium. The exposure to GO induced more acidic pH values of the culture media after 7 d. GO induced the disruption of the fiber structure of P. chrysosporium, while at 4 mg/mL some very long and thick fibers were formed. Such changes were reflected in the scanning electron microscopy investigations, where the disruption of fibers was observed. In the ultrastructural investigations, the shape of P. chrysosporium cells changed and more vesicles were found upon the exposure to GO. The infrared spectroscopy analyses suggested that the chemical compositions of mycelia were not changed qualitatively. Beyond the toxicity, GO did not alter the activities of P. chrysosporium at low concentrations, but led to the complete loss of activity at high concentrations. The implication to the ecological safety of graphene is discussed. PMID:26950023

  3. Evidence from Serpula lacrymans that 2,5-dimethoxyhydroquinone Is a lignocellulolytic agent of divergent brown rot basidiomycetes.

    Science.gov (United States)

    Korripally, Premsagar; Timokhin, Vitaliy I; Houtman, Carl J; Mozuch, Michael D; Hammel, Kenneth E

    2013-04-01

    Basidiomycetes that cause brown rot of wood are essential biomass recyclers in coniferous forest ecosystems and a major cause of failure in wooden structures. Recent work indicates that distinct lineages of brown rot fungi have arisen independently from ligninolytic white rot ancestors via loss of lignocellulolytic enzymes. Brown rot thus proceeds without significant lignin removal, apparently beginning instead with oxidative attack on wood polymers by Fenton reagent produced when fungal hydroquinones or catechols reduce Fe(3+) in colonized wood. Since there is little evidence that white rot fungi produce these metabolites, one question is the extent to which independent lineages of brown rot fungi may have evolved different Fe(3+) reductants. Recently, the catechol variegatic acid was proposed to drive Fenton chemistry in Serpula lacrymans, a brown rot member of the Boletales (D. C. Eastwood et al., Science 333:762-765, 2011). We found no variegatic acid in wood undergoing decay by S. lacrymans. We found also that variegatic acid failed to reduce in vitro the Fe(3+) oxalate chelates that predominate in brown-rotting wood and that it did not drive Fenton chemistry in vitro under physiological conditions. Instead, the decaying wood contained physiologically significant levels of 2,5-dimethoxyhydroquinone, a reductant with a demonstrated biodegradative role when wood is attacked by certain brown rot fungi in two other divergent lineages, the Gloeophyllales and Polyporales. Our results suggest that the pathway for 2,5-dimethoxyhydroquinone biosynthesis may have been present in ancestral white rot basidiomycetes but do not rule out the possibility that it appeared multiple times via convergent evolution. PMID:23377930

  4. Black hole evaporation in an expanding universe

    International Nuclear Information System (INIS)

    We calculate the quantum radiation power of black holes which are asymptotic to the Einstein-de Sitter universe at spatial and null infinities. We consider two limiting mass accretion scenarios, no accretion and significant accretion. We find that the radiation power strongly depends on not only the asymptotic condition but also the mass accretion scenario. For the no accretion case, we consider the Einstein-Straus solution, where a black hole of constant mass resides in the dust Friedmann universe. We find negative cosmological correction besides the expected redshift factor. This is given in terms of the cubic root of ratio in size of the black hole to the cosmological horizon, so that it is currently of order 10-5(M/106Mo-dot)1/3(t/14Gyr)-1/3 but could have been significant at the formation epoch of primordial black holes. Due to the cosmological effects, this black hole has not settled down to an equilibrium state. This cosmological correction may be interpreted in an analogy with the radiation from a moving mirror in a flat spacetime. For the significant accretion case, we consider the Sultana-Dyer solution, where a black hole tends to increase its mass in proportion to the cosmological scale factor. In this model, we find that the radiation power is apparently the same as the Hawking radiation from the Schwarzschild black hole of which mass is that of the growing mass at each moment. Hence, the energy loss rate decreases and tends to vanish as time proceeds. Consequently, the energy loss due to evaporation is insignificant compared to huge mass accretion onto the black hole. Based on this model, we propose a definition of quasi-equilibrium temperature for general conformal stationary black holes

  5. Functional Genomics of Lignocellulose Degradation in the Basidiomycete White Rot Schizophyllum commune

    Energy Technology Data Exchange (ETDEWEB)

    Ohm, Robin A. [Joint Genome Inst., Walnut Creek, CA (United States); Tegelaar, Martin [Utrecht Univ. (Netherlands); Henrissat, Bernard [Univ. of Marseille (France); Brewer, Heather M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Purvine, Samuel O. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Baker, Scott [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wosten, Han A. B. [Utrecht Univ. (Netherlands); Grigoriev, Igor V. [Joint Genome Inst., Walnut Creek, CA (United States); Lugones, Luis G. [Utrecht Univ. (Netherlands)

    2013-03-01

    White and brown rot fungi are among the most important wood decayers in nature. Although more than 50 genomes of Basidiomycete white and brown rots have been sequenced by the Joint Genome Institute, there is still a lot to learn about how these fungi degrade the tough polymers present in wood. In particular, very little is known about how these fungi regulate the expression of genes involved in lignocellulose degradation. Here, we used transcriptomics, proteomics, and promoter analysis in an effort to gain insight into the process of lignocellulose degradation.

  6. Report of postharvest rot of kiwifruit in Korea caused by Sclerotinia sclerotiorum.

    Science.gov (United States)

    Lee, Jung Han; Kwon, Young Ho; Kwack, Yong-Bum; Kwak, Youn-Sig

    2015-08-01

    In May 2014, sclerotinia rot symptoms caused by Sclerotinia sclerotiorum were observed on stored kiwifruit in Jinju, South Korea. The symptoms appeared as soft, water-soaked lesions on fruit covered with a white mycelium. The morphological characteristics and the internal transcribed spacer sequences of rRNA of the pathogen isolated from the sclerotinia rot showed it to be S. sclerotiorum. This was confirmed by performing a pathogenicity test with pure cultures of S. sclerotiorum and by reisolating S. sclerotiorum from artificially inoculated kiwifruits. Our results should help promote a better understanding of the diseases that affect kiwifruit and improve practices for postharvest disease control in the kiwifruit industry. PMID:25996522

  7. Analysis of pectate lyases produced by soft rot bacteria associated with spoilage of vegetables.

    OpenAIRE

    Liao, C.H.

    1989-01-01

    Isoelectric focusing (IEF) profiles of pectate lyases (PLs) produced by five different groups of soft rot bacteria were analyzed by using the combined techniques of thin-layer polyacrylamide gel IEF and agarose-pectate overlay activity staining. Four strains of soft rot Erwinia spp. produced three or more PL isozymes. All of eight Pseudomonas viridiflava strains examined produced one single PL with a pI of 9.7. All 10 of Pseudomonas fluorescens strains produced two PLs; the major one had a pI...

  8. Occurrence of Fruit Rot of Melon Caused by Sclerotium rolfsii in Korea

    OpenAIRE

    Kwon, Jin-Hyeuk; Chi, Tran Thi Phuong; Park, Chang-Seuk

    2009-01-01

    In 2007 to 2008, a fruit rot of Melon (Cucumis melo L.) caused by Sclerotium rolfsii occurred sporadically in a farmer's vinyl house in Jinju City. The symptoms started with watersoaking lesion and progressed into the rotting of the surface of fruit. White mycelial mats appeared on the lesion at the surface of the fruit and a number of sclerotia formed on the fruit near the soil line. The sclerotia were globoid in shape, 1~3 mm in size, and white to brown in color. The hyphal width was measur...

  9. The susceptibility of bananas to crown rot disease is influenced by geographical and seasonal effects

    OpenAIRE

    Ewane, Cécile Annie; Lassois, Ludivine; Lepoivre, Philippe; Brostaux, Yves; de Lapeyre de Bellaire, Luc

    2013-01-01

    Crown rot of banana fruits is caused by a complex of fungal pathogens, the most common of which is Colletotrichum musae, and is one of the main quality defects of exported bananas. Susceptibility of banana fruits to crown rot is influenced by many pre-harvest factors. The aim of this study was to improve on the methodology for the evaluation of fruit susceptibility and to verify whether cultivation areas in Cameroon as well as seasonal variations have an influence on the susceptibility to cro...

  10. Evaluation of some garlic (Allium Sativum L.) mutants resistant to white rot disease by RAPD analysis

    International Nuclear Information System (INIS)

    Random amplified polymorphic DNA (RAPD) analysis was used to evaluate genetic diversity among eight garlic mutants resistant to white rot disease (Sclerotium cepivorum) and two controls. Twelve of 13 synthetic random primers were found to identify polymorphism in amplification products. Mutants characterised with moderate resistance to white rot were closely related to the control using cluster and correlation analyses. On the other hand, highly resistant mutants were quite distant from the control with low correlation coefficients. The banding patterns produced by primer OPB-15 (GGAAGGGTGTT) with highly resistant mutants may be used as genetic markers for early selection of resistant plants. (author)

  11. Analysis of Fusarium avenaceum Metabolites Produced during Wet Apple Core Rot

    DEFF Research Database (Denmark)

    Sørensen, Jens Laurids; Phipps, Richard Kerry; Nielsen, Kristian Fog;

    2009-01-01

    Wet apple core rot (wACR) is a well-known disease of susceptible apple cultivars such as Gloster, Jona Gold, and Fuji. Investigations in apple orchards in Slovenia identified Fusarium avenaceum, a known producer of several mycotoxins, as the predominant causal agent of this disease. A LC-MS/MS me......Wet apple core rot (wACR) is a well-known disease of susceptible apple cultivars such as Gloster, Jona Gold, and Fuji. Investigations in apple orchards in Slovenia identified Fusarium avenaceum, a known producer of several mycotoxins, as the predominant causal agent of this disease. A LC...

  12. ROOT User Workshop 2013

    CERN Document Server

    2013-01-01

    Since almost two decades, ROOT has established itself as the framework for HENP data processing and analysis. The LHC upgrade program and the new experiments being designed at CERN and elsewhere will pose even more formidable challenges in terms of data complexity and size. The new parallel and heterogeneous computing architectures that are either announced or already available will call for a deep rethinking of the code and the data structures to be exploited efficiently. This workshop, following from a successful series of such events, will allow you to learn in detail about the new ROOT 6 and will help shape the future evolution of ROOT.

  13. Black Silicon Solar Cells with Black Ribbons

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io;

    2016-01-01

    We present the combination of mask-less reactive ion etch (RIE) texturing and blackened interconnecting ribbons as a method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon made by mask-less reactive ion etching has total, average...... range 15.7-16.3%. The KOH-textured reference cell had an efficiency of 17.9%. The combination of black Si and black interconnecting ribbons may result in aesthetic, all-black panels based on conventional, front-contacted silicon solar cells....... reflectance below 0.5% across a 156x156 mm2 silicon (Si) wafer. Black interconnecting ribbons were realized by oxidizing copper resulting in reflectance below 3% in the visible wavelength range. Screen-printed Si solar cells were realized on 156x156 mm2 black Si substrates with resulting efficiencies in the...

  14. Arbitrary Dimensional Schwarzschild-FRW Black Holes

    OpenAIRE

    Gao, Chang Jun

    2004-01-01

    The metric of arbitrary dimensional Schwarzschild black hole in the background of Friedman-Robertson-Walker universe is presented in the cosmic coordinates system. In particular, the arbitrary dimensional Schwarzschild-de Sitter metric is rewritten in the Schwarzschild coordinates system and basing on which the even more generalized higher dimensional Schwarzschild-de Sitter metric with another extra dimensions is found. The generalized solution shows that the cosmological constant may roots ...

  15. Noncommutative black holes

    International Nuclear Information System (INIS)

    We study noncommutative black holes, by using a diffeomorphism between the Schwarzschild black hole and the Kantowski-Sachs cosmological model, which is generalized to noncommutative minisuperspace. Through the use of the Feynman-Hibbs procedure we are able to study the thermodynamics of the black hole, in particular, we calculate Hawking's temperature and entropy for the 'noncommutative' Schwarzschild black hole

  16. Black Entrepreneurship in America.

    Science.gov (United States)

    Green, Shelley; Pryde, Paul

    The economic condition of black Americans is discussed, proceeding from the assumption that black economic progress does not depend on a renewed struggle for unobtained civil rights, but rather on the creative response of black Americans to economic opportunity and problems. In the long run, black economic development must rely on the…

  17. Quantitative measurements of root water uptake and root hydraulic conductivities

    Science.gov (United States)

    Zarebanadkouki, Mohsen; Javaux, Mathieu; Meunier, Felicien; Couvreur, Valentin; Carminati, Andrea

    2016-04-01

    How is root water uptake distributed along the root system and what root properties control this distribution? Here we present a method to: 1) measure root water uptake and 2) inversely estimate the root hydraulic conductivities. The experimental method consists in using neutron radiography to trace deuterated water (D2O) in soil and roots. The method was applied to lupines grown aluminium containers filled with a sandy soil. When the lupines were 4 weeks old, D2O was locally injected in a selected soil regions and its transport was monitored in soil and roots using time-series neutron radiography. By image processing, we quantified the concentration of D2O in soil and roots. We simulated the transport of D2O into roots using a diffusion-convection numerical model. The diffusivity of the roots tissue was inversely estimated by simulating the transport of D2O into the roots during night. The convective fluxes (i.e. root water uptake) were inversely estimating by fitting the experiments during day, when plants were transpiring, and assuming that root diffusivity did not change. The results showed that root water uptake was not uniform along the roots. Water uptake was higher at the proximal parts of the lateral roots and it decreased by a factor of 10 towards the distal parts. We used the data of water fluxes to inversely estimate the profile of hydraulic conductivities along the roots of transpiring plants growing in soil. The water fluxes in the lupine roots were simulated using the Hydraulic Tree Model by Doussan et al. (1998). The fitting parameters to be adjusted were the radial and axial hydraulic conductivities of the roots. The results showed that by using the root architectural model of Doussan et al. (1998) and detailed information of water fluxes into different root segments we could estimate the profile of hydraulic conductivities along the roots. We also found that: 1) in a tap-rooted plant like lupine water is mostly taken up by lateral roots; (2) water

  18. Genetic association among root morphology, root quality and root yield in ashwagandha (Withania somnifera

    Directory of Open Access Journals (Sweden)

    Kumar Ramesh R.

    2011-01-01

    Full Text Available Ashwagandha (Withania somnifera is a dryland medicinal crop and roots are used as valuable drug in traditional systems of medicine. Morphological variants (morphotypes and the parental populations were evaluated for root - morphometric, quality and yield traits to study genetic association among them. Root morphometric traits (root length, root diameter, number of secondary roots/ plant and crude fiber content exhibited strong association among them and showed significant positive genotypic correlation with yield. Starch-fiber ratio (SFR, determinant of brittle root texture showed strong negative association with root yield. The total alkaloid content had positive genotypic correlation with root yield. So genetic upgradation should aim at optimum balance between two divergent groups of traits i.e. root yield traits (root morphometric traits and crude fiber content and root textural quality traits (starch content and SFR to develop superior genotypes with better yield and quality.

  19. Black Travesty

    Directory of Open Access Journals (Sweden)

    Angela Khristin Brown

    2013-01-01

    Full Text Available Quincy Troupe is a visionary poet who is always reaching out to walk and dance words upon a single page. Quincy uses his imagination through dialog with certain looks of rhythm of words which bounce off the page of unforgotton sound. Quincy prances accross word that burst from childhood dreams that make you smile. Perhaps there is an explanation to why he creates hope to the deturbed voices in our head. It is through language that he decodes similes, metaphores and apostrophes out of clarity that trace our roots to our dark past which is from the eye of the beholder. Quincy's words bounce back at us with words of wisdom from the voice that humms in our head. Quincy maps his experience into beautiful shcemes of imprisoned thought. Quincy has mirrored a managerie of space on a blank page using pain and agony to slowly develop an illusion for movement. Quincy's sentex is the blues in space that echoes in the air in spoken tongues. It is from dreams we pulsate life through shared idioms of time. When we can identify in how sorrow has touched our lives, we believe in fear itself will keep us alive. Fear is an invisible ploom we live through rituals from desire. It is from this madness we imagine love is far deeper than fear itself. 

  20. Decolorization of reactive brilliant red K-2BP by white rot fungus under sterile and non-sterile conditions

    Institute of Scientific and Technical Information of China (English)

    GAO Da-wen; WEN Xiang-hua; QIAN Yi

    2006-01-01

    Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is treated under sterile conditions. A feasible study was made for using white rot fungus Phanerochaete chrysosporium to degrade reactive brilliant red K-2BP dye under non-sterile conditions. The results showed that there was no decolorizing effect under non-sterile condition if white rot fungus was incubated under non-sterile condition, and the decolorization was always near to 0% during decolorizing test for 3 d; in the meantime, a lot of yeast funguses were found in liquid medium when white rot fungus was incubated under non-sterile conditions; however, if white rot fungus was incubated under sterile condition firstly, its decolorization was above 90% under non-sterile condition, which was similar to that of sterile condition. So we point out that the treating process for wastewater with dyes should be divided into two stages. The first stage is that white rot fungus should be incubated under sterile conditions, and the second stage is that reactive brilliant red K-2BP is decolorized under non-sterile conditions. The method not only save the operation cost which decolorizing reactive brilliant red K-2BP under sterile condition, but also provide the feasibility for using white rot fungus to degrade wastewater with dyes under non-sterile conditions.

  1. Biocontrol of Fusarium Crown and Root Rot and Promotion of Growth of Tomato by Paenibacillus Strains Isolated from Soil

    OpenAIRE

    Xu, Sheng Jun; Kim, Byung Sup

    2014-01-01

    In this study, bacterial strains were isolated from soils from 30 locations of Samcheok, Gangwon province. Of the isolated strains, seven showed potential plant growth promoting and antagonistic activities. Based on cultural and morphological characterization, and 16S rRNA gene sequencing, these strains were identified as Paenibacillus species. All seven strains produced ammonia, cellulase, hydrocyanic acid, indole-3-acetic acid, protease, phosphatase, and siderophores. They also inhibited th...

  2. Root-rot diseases of the rubber tree in the Ivory Coast : 1. Severity, dynamics, and characterization of epidemics

    OpenAIRE

    Nandris, Daniel; Nicole, Michel; Geiger, Jean-Paul

    1988-01-01

    Une enquête épidémiologique a été menée pendant 6 ans dans une jeune plantation d'hévéa (#Hevea brasiliensis$ Willd. ex A. Juss) afin d'étudier et de prévoir le développement des champignons agents de pourridié, #Rigidoporus lignosus$ (Klotzsch) Imazeki et #Phellinus noxius$ (Corner) G. Cunn. Pendant cette période, la contamination et la mortalité de ces arbres ont été systématiquement prises en compte tous les 6 mois. Durant la première année, on a assisté à une explosion de la maladie se tr...

  3. Transferring Sclerotinia stalk rot resistance genes from wild Helianthus species into cultivated sunflower

    Science.gov (United States)

    Replicated field tests of 313 progeny families screened for stalk rot resistance at Carrington, ND in 2009 showed good introgression of resistance genes. These materials were planted again in 2010 for a second year of field evaluation, as well as the new families with seed increased in 2009. In 2010...

  4. Identifying quantitative trait loci for resistance to Sclerotinia head rot in two USDA sunflower germplasms

    Science.gov (United States)

    One hundred and twenty-three F2:3 and F2:4 families derived from a cross between HA 441 and RHA 439, both showing partial tolerance to Sclerotinia head rot, were used for the current study. A genetic map with180 TRAP, 32 SSR, 11 ZVG INDEL, and 2 morphological markers was constructed. The map has 19 ...

  5. Treatment of olive mill waste waters by white-rot fungi and radicals-generating reactions

    Czech Academy of Sciences Publication Activity Database

    Nerud, František; Zervakis, G.; Baldrian, Petr; Ehaliotis, C.; Ntougias, S.; Merhautová, Věra

    Chania, 2005, s. 1-4. [European Bioremediation Conference /3./. Chania (GR), 04.07.2005-07.07.2005] R&D Projects: GA MŠk ME 686 Institutional research plan: CEZ:AV0Z50200510 Keywords : white-rot fungi * decolorization Subject RIV: EE - Microbiology, Virology

  6. Improving ruminal degradability of oil palm fronds using white rot fungi

    NARCIS (Netherlands)

    Rahman, M.M.; Lourenco, M.; Hassim, H.A.; Baars, J.J.P.; Sonnenberg, A.S.M.; Cone, J.W.; Boever, de J.L.; Fievez, V.

    2011-01-01

    The use of oil palm fronds (OPF) in livestock production is limited as up to 0.20 of their dry biomass is lignin. White rot fungi (WRF) are very effective basidiomycetes for biological pre-treatment as they degrade lignin extensively. Ten WRF were screened for their potential to increase OPF digesti

  7. Resident bacteria of plums and their potential for controlling brown rot after harvest

    Science.gov (United States)

    Fruit microflora has been the richest source of antagonists against fruit decays and the active ingredient in all currently available commercial biocontrol products. A comprehensive evaluation of plum bacteria for biocontrol activity against Monilinia fructicola, causing brown rot of stone fruit, w...

  8. Characterization of Basidiomycetes associated with wood rot of citrus in southern Italy.

    Science.gov (United States)

    Roccotelli, Angela; Schena, Leonardo; Sanzani, Simona M; Cacciola, Santa O; Mosca, Saveria; Faedda, Roberto; Ippolito, Antonio; di San Lio, Gaetano Magnano

    2014-08-01

    The characterization of Basidiomycetes associated with wood rots in commercial citrus orchards in southern Italy revealed that both white and brown rot fungi are implicated in this disease. Fomitiporia mediterranea was the most prevalent species causing a white rot, followed by Fomitopsis sp. which, by contrast, was associated with brown rot wood decay. Furthermore, Phellinus spp. and other nonidentified basidiomycetous fungi showing genetic affinity with the genera Phellinus and Coniophora were occasionally isolated. Artificial inoculations on lemon (Citrus limon) branches showed a faster wood colonization by Fomitopsis sp. compared with F. mediterranea, indicating that the former species as a potentially serious pathogen of citrus trees. The analysis of F. mediterranea internal transcribed spacer (ITS) sequences revealed a high level of genetic variability, with 13 genotypes which were both homozygous (6 genotypes) and heterozygous (7 genotypes). The presence of heterozygous genomes based on ITS sequences has never been reported before for F. mediterranea. This, together with the high frequency of basidiomata on infected wood, unambiguously confirms the outcrossing nature of reproduction in F. mediterranea and the primary role of basidiospores in the dissemination of inoculum. Similarly, high genetic variability was observed analyzing Fomitopsis sp. Because basidiomata of this fungus have not been observed on citrus trees, it can be hypothesized that basidiospores are produced on alternative host plants. PMID:24502208

  9. Short read sequencing for Genomic Analysis of the brown rot fungus Fibroporia radiculosa

    Science.gov (United States)

    The practical capability of short read sequencing for whole genome gene prediction was investigated for Fibroporia radiculosa, a copper-tolerant basidiomycete fungus that causes brown rot decay of wood. Illumina GAIIX reads from a single run of a paired-end library (75 nt read length, 300 bp insert...

  10. Control of brown rot of stone fruits by brief heated water immersion treatments

    Science.gov (United States)

    The effectiveness of brief (30 or 60 s) immersion in water at 24, 50, 55, 60, 65, or 70 ºC was evaluated for the control of brown rot, caused by Monilinia fructicola, on California-grown peaches, nectarines, and plums. Inoculated fruits were treated and either stored at 20 ºC for 5 days or at 0 ºC f...

  11. Culturable bacteria from plum fruit surfaces and their potential for controlling brown rot after harvest

    Science.gov (United States)

    Fruit microflora has been the richest source of antagonists against fruit decays and the active ingredient in all currently available commercial biocontrol products. A comprehensive evaluation of plum bacteria for biocontrol activity against Monilinia fructicola, causing brown rot of stone fruit, w...

  12. Incidence and Severity of Maize Ear Rots and Factors Responsible for Their Occurrence in Uganda

    Science.gov (United States)

    Bigirwa, G.; Kaaya, A. N.; Sseruwu, G.; Adipala, E.; Okanya, S.

    Eleven major maize growing districts of Uganda were surveyed for three consecutive seasons between 2002 and 2003 to establish maize ear rot incidence and severity. Sternocarpella maydis and Fusarium species particularly F. graminearum and F. verticillioides were the identified maize ear rot causing fungi. Incidence of S. maydis ranged from 2.5 to 32.5% while that of Fusarium sp. was in the range of 1.9 and 15.3%. In districts of higher altitude (above 1,800 m above sea level) F. graminearum dominated in all seasons while in districts with an altitude between 900 and 1,500 m above sea level, S. maydis was the major cause of ear rots. This observation was attributed to differences in temperature, altitude and rainfall. There was a strong positive correlation (p = 0.001) between incidence and severity for S. maydis and a weak one for Fusarium sp. because the latter would rarely infect the entire cob unlike the former. All farmers expressed concern about the quality of maize due to ear rots and sort out infected grain after harvest. However, varied uses of infected grain were noted. For example, in Kapchorwa district 82% of the respondents indicated that the infected grain is used for making local brew because the moulds give it a good taste and aroma, while in Kamuli and Masaka districts, 36% use it as animal feed ingredient. This indicates that people and animals could be ingesting mycotoxins unknowingly thus the need for sensitization programmes.

  13. HORMONAL ACTIVITIES OF NOVEL BROMINATED FLAME RETARDANTS AND THEIR BIODEGRADATION BY WHITE ROT FUNGI

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Svobodová, Kateřina; Cajthaml, Tomáš

    2012-01-01

    Roč. 11, č. 3 (2012), s. 233-233. ISSN 1843-3707. [ Environmental Microbiology and Biotechnology. 10.04.2012-12.04.2012, Bologna] R&D Projects: GA TA ČR TA01020804 Institutional research plan: CEZ:AV0Z50200510 Keywords : white rot fungi Subject RIV: EE - Microbiology, Virology

  14. First report of Gliocephalotrichum bulbilium and G. simplex causing fruit rot of rambutan in Puerto Rico

    Science.gov (United States)

    Worldwide, significant post-harvest disease losses of rambutan (Nephelium lappaceum L.) have been reported and several pathogens have been associated with fruit rot. Even though rambutan was introduced to Puerto Rico in 1927, it was not until 1998 that commercial farms were established in the wester...

  15. Phylogenetic, morphological and pathogenic characterization of Alternaria species associated with fruit rots of blueberry in California

    Science.gov (United States)

    Fruit rot caused by Alternaria spp. is one of the most important factors affecting the postharvest quality and shelf life of blueberry fruits. Alternaria spp. isolates were collected from decayed fruits of blueberry in the Central Valley of California during 2012 and 2013. The aims of this study wer...

  16. Organics and mineral fertilizers and biological control on the incidence of stalk rot and corn yield

    Directory of Open Access Journals (Sweden)

    Elena Blume

    2014-06-01

    Full Text Available The expansion of area under maize (Zea mays L. and the use of no tillage have favored the incidence of stalk rot on this crop. The study aimed to evaluate the organic fertilizers and the treatment of corn seeds with Trichoderma spp. on the production of dry matter (DM of shoot, incidence of stalk rot and corn yield. The experiment consisted in a factorial with split-plot in strips, on the randomized block design with four replicates, and the fertilization treatments (pig slurry; swine deep bedding; cattle slurry; mineral fertilizer; control treatment were applied to the plots and the seeds treatment (with and without Trichoderma spp. in the subplots. At the flowering stage, three corn plants per subplot were collected for the assessment of DM production. At physiological maturity stage, the incidence of stalk rot was assessed, and the ears of corn harvested for productivity assessment. The organic and mineral fertilizers increased the production of DM and productivity of corn. Trichoderma spp. increased the production of DM of corn, but had no reflection on productivity. The incidence of stalk rot in corn was higher in treatments with organic and mineral fertilization. Organic fertilizers increase dry matter production of shoot and corn yield, and Trichoderma spp. provides an increase in dry matter production of shoot.

  17. Draft Genome Sequence of a Virulent Pectobacterium carotovorum subsp. brasiliense Isolate Causing Soft Rot of Cucumber.

    Science.gov (United States)

    Onkendi, Edward M; Ramesh, Aadi Moolam; Kwenda, Stanford; Naidoo, Sanushka; Moleleki, Lucy

    2016-01-01

    Pectobacterium carotovorum subsp. brasiliense causes soft rot and blackleg diseases on potatoes, ornamentals, and other crops of economic importance. Here, we report a draft genome sequence of a highly virulent P. carotovorum subsp. brasiliense strain, PcbHPI01, isolated from a cucumber in South Africa. PMID:26744374

  18. CONTROL OF BACTERIAL SOFT ROT AND FOODBORNE HUMAN PATHOGENS ON FRESH FRUITS AND VEGETABLES

    Science.gov (United States)

    Production and sale of fresh fruits and vegetables in the U.S. has increased very sharply over the two decades. This chapter will address two most important problems now facing the fresh produce industry; one is to reduce the losses caused by bacterial soft rot and the other to reduce the safety ri...

  19. Genome Sequence of the Banana Pathogen Dickeya zeae Strain MS1, Which Causes Bacterial Soft Rot

    OpenAIRE

    Zhang, Jing-Xin; Lin, Bi-Run; Shen, Hui-Fang; Pu, Xiao-Ming

    2013-01-01

    We report a draft genome sequence of Dickeya zeae strain MS1, which is the causative agent of banana soft rot in China, and we show several of its specific properties compared with those of other D. zeae strains. Genome sequencing provides a tool for understanding the genomic determination of the pathogenicity and phylogeny placement of this pathogen.

  20. Incidence and Severity of Maize Ear Rots and Factors Responsible for Their Occurrence in Uganda

    Directory of Open Access Journals (Sweden)

    G. Bigirwa

    2007-01-01

    Full Text Available Eleven major maize growing districts of Uganda were surveyed for three consecutive seasons between 2002 and 2003 to establish maize ear rot incidence and severity. Sternocarpella maydis and Fusarium species particularly F. graminearum and F. verticillioides were the identified maize ear rot causing fungi. Incidence of S. maydis ranged from 2.5 to 32.5% while that of Fusarium sp. was in the range of 1.9 and 15.3%. In districts of higher altitude (above 1,800 m above sea level F. graminearum dominated in all seasons while in districts with an altitude between 900 and 1,500 m above sea level, S. maydis was the major cause of ear rots. This observation was attributed to differences in temperature, altitude and rainfall. There was a strong positive correlation (p = 0.001 between incidence and severity for S. maydis and a weak one for Fusarium sp. because the latter would rarely infect the entire cob unlike the former. All farmers expressed concern about the quality of maize due to ear rots and sort out infected grain after harvest. However, varied uses of infected grain were noted. For example, in Kapchorwa district 82% of the respondents indicated that the infected grain is used for making local brew because the moulds give it a good taste and aroma, while in Kamuli and Masaka districts, 36% use it as animal feed ingredient. This indicates that people and animals could be ingesting mycotoxins unknowingly thus the need for sensitization programmes.