WorldWideScience

Sample records for common root rot

  1. Root rots

    Science.gov (United States)

    Kathryn Robbins; Philip M. Wargo

    1989-01-01

    Root rots of central hardwoods are diseases caused by fungi that infect and decay woody roots and sometimes also invade the butt portion of the tree. By killing and decaying roots, root rotting fungi reduce growth, decrease tree vigor, and cause windthrow and death. The most common root diseases of central hardwoods are Armillaria root rot, lnonotus root rot, and...

  2. 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...

  3. 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.

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

    International Nuclear Information System (INIS)

    Arabi, M.I.E.; Jawhar, M.

    2003-01-01

    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

  5. Pythium root rot of common bean: biology and control methods. A review

    Directory of Open Access Journals (Sweden)

    Baudoin, JP.

    2012-01-01

    Full Text Available Pythium root rot constitutes a highly damaging constraint on the common bean, Phaseolus vulgaris L., grown in several areas of Eastern and Central Africa. Here, this food legume is cultivated intensively under poor conditions of crop rotation due to the exiguity of the land in the region. Yield losses of up to 70% in traditional local bean cultivars have been reported in Kenya and Rwanda. In this study, a detailed analysis of the biology and diversity of the Pythium genus was carried out in order to understand the mechanisms leading to the development of the disease. Various control methods for reducing the damage provoked by this disease were analyzed.

  6. QTL analysis of Fusarium root rot resistance in an Andean x Middle American common bean RIL population

    Science.gov (United States)

    Aims Fusarium root rot (FRR) is a soil-borne disease that constrains common bean (Phaseolus vulgaris L.) production. FRR causal pathogens include clade 2 members of the Fusarium solani species complex. Here we characterize common bean reaction to four Fusarium species and identify genomic regions as...

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

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    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.

  8. Wilt, crown, and root rot of common rose mallow (Hibiscus moscheutos) caused by a novel Fusarium sp

    Science.gov (United States)

    A new crown and root rot disease of landscape plantings of the malvaceous ornamental common rose mallow (Hibiscus moscheutos) was first detected in Washington State in 2012. The main objectives of this study were to complete Koch's postulates, document the disease sypmtoms photographically, and iden...

  9. GmPGIP3 enhanced resistance to both take-all and common root rot diseases in transgenic wheat.

    Science.gov (United States)

    Wang, Aiyun; Wei, Xuening; Rong, Wei; Dang, Liang; Du, Li-Pu; Qi, Lin; Xu, Hui-Jun; Shao, Yanjun; Zhang, Zengyan

    2015-05-01

    Take-all (caused by the fungal pathogen Gaeumannomyces graminis var. tritici, Ggt) and common root rot (caused by Bipolaris sorokiniana) are devastating root diseases of wheat (Triticum aestivum L.). Development of resistant wheat cultivars has been a challenge since no resistant wheat accession is available. GmPGIP3, one member of polygalacturonase-inhibiting protein (PGIP) family in soybean (Glycine max), exhibited inhibition activity against fungal endopolygalacturonases (PGs) in vitro. In this study, the GmPGIP3 transgenic wheat plants were generated and used to assess the effectiveness of GmPGIP3 in protecting wheat from the infection of Ggt and B. sorokiniana. Four independent transgenic lines were identified by genomic PCR, Southern blot, and reverse transcription PCR (RT-PCR). The introduced GmPGIP3 was integrated into the genomes of these transgenic lines and could be expressed. The expressing GmPGIP3 protein in these transgenic wheat lines could inhibit the PGs produced by Ggt and B. sorokiniana. The disease response assessments postinoculation showed that the GmPGIP3-expressing transgenic wheat lines displayed significantly enhanced resistance to both take-all and common root rot diseases caused by the infection of Ggt and B. sorokiniana. These data suggested that GmPGIP3 is an attractive gene resource in improving resistance to both take-all and common root rot diseases in wheat.

  10. Potential worldwide distribution of Fusarium dry root rot in common beans based on the optimal environment for disease occurrence.

    Science.gov (United States)

    Macedo, Renan; Sales, Lilian Patrícia; Yoshida, Fernanda; Silva-Abud, Lidianne Lemes; Lobo, Murillo

    2017-01-01

    Root rots are a constraint for staple food crops and a long-lasting food security problem worldwide. In common beans, yield losses originating from root damage are frequently attributed to dry root rot, a disease caused by the Fusarium solani species complex. The aim of this study was to model the current potential distribution of common bean dry root rot on a global scale and to project changes based on future expectations of climate change. Our approach used a spatial proxy of the field disease occurrence, instead of solely the pathogen distribution. We modeled the pathogen environmental requirements in locations where in-situ inoculum density seems ideal for disease manifestation. A dataset of 2,311 soil samples from commercial farms assessed from 2002 to 2015 allowed us to evaluate the environmental conditions associated with the pathogen's optimum inoculum density for disease occurrence, using a lower threshold as a spatial proxy. We encompassed not only the optimal conditions for disease occurrence but also the optimal pathogen's density required for host infection. An intermediate inoculum density of the pathogen was the best disease proxy, suggesting density-dependent mechanisms on host infection. We found a strong convergence on the environmental requirements of both the host and the disease development in tropical areas, mostly in Brazil, Central America, and African countries. Precipitation and temperature variables were important for explaining the disease occurrence (from 17.63% to 43.84%). Climate change will probably move the disease toward cooler regions, which in Brazil are more representative of small-scale farming, although an overall shrink in total area (from 48% to 49% in 2050 and 26% to 41% in 2070) was also predicted. Understanding pathogen distribution and disease risks in an evolutionary context will therefore support breeding for resistance programs and strategies for dry root rot management in common beans.

  11. Potential worldwide distribution of Fusarium dry root rot in common beans based on the optimal environment for disease occurrence.

    Directory of Open Access Journals (Sweden)

    Renan Macedo

    Full Text Available Root rots are a constraint for staple food crops and a long-lasting food security problem worldwide. In common beans, yield losses originating from root damage are frequently attributed to dry root rot, a disease caused by the Fusarium solani species complex. The aim of this study was to model the current potential distribution of common bean dry root rot on a global scale and to project changes based on future expectations of climate change. Our approach used a spatial proxy of the field disease occurrence, instead of solely the pathogen distribution. We modeled the pathogen environmental requirements in locations where in-situ inoculum density seems ideal for disease manifestation. A dataset of 2,311 soil samples from commercial farms assessed from 2002 to 2015 allowed us to evaluate the environmental conditions associated with the pathogen's optimum inoculum density for disease occurrence, using a lower threshold as a spatial proxy. We encompassed not only the optimal conditions for disease occurrence but also the optimal pathogen's density required for host infection. An intermediate inoculum density of the pathogen was the best disease proxy, suggesting density-dependent mechanisms on host infection. We found a strong convergence on the environmental requirements of both the host and the disease development in tropical areas, mostly in Brazil, Central America, and African countries. Precipitation and temperature variables were important for explaining the disease occurrence (from 17.63% to 43.84%. Climate change will probably move the disease toward cooler regions, which in Brazil are more representative of small-scale farming, although an overall shrink in total area (from 48% to 49% in 2050 and 26% to 41% in 2070 was also predicted. Understanding pathogen distribution and disease risks in an evolutionary context will therefore support breeding for resistance programs and strategies for dry root rot management in common beans.

  12. Improvement of resistance to Fusarium root rot through gene ...

    African Journals Online (AJOL)

    Fusarium root rot (FRR), caused by Fusarium solani f.sp. , is one of the most serious root rot diseases of common bean (Phaseolus vulgaris L.) throughout the world. Yield losses of up to 84% have been attributed to the disease. Development and deployment of resistant materials is the most feasible approach to managing ...

  13. Root rot in sugar beet piles at harvest

    Science.gov (United States)

    Sugar beet root rots are not only a concern because of reduced yields, but can also be associated with losses in storage. Our primary sugar beet root rot disease problem in the Amalgamated production area is Rhizoctonia root rot. However, this rot frequently only penetrates a short distance past t...

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

    International Nuclear Information System (INIS)

    Johansson, Mats

    1997-01-01

    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

  15. Laminated Root Rot of Western Conifers

    Science.gov (United States)

    E.E. Nelson; N.E. Martin; R.E. Williams

    1981-01-01

    Laminated root rot is caused by the native fungus Phellinus weirii (Murr.) Gilb. It occurs throughout the Northwestern United States and in southern British Columbia, Canada. The disease has also been reported in Japan and Manchuria. In the United States, the pathogen is most destructive in pure Douglas-fir stands west of the crest of the Cascade Range in Washington...

  16. Rhizoctonia crown and root rot disease nursery

    Science.gov (United States)

    The BSDF cooperative CRR Eastern Evaluation Nursery Rhizoctonia crown and root rot Evaluation Nursery in 2016 was a randomized complete-block design with five replications in 15 feet long, one-row plots (20 in row spacing), at the Saginaw Valley Research and Education Center near Frankenmuth, MI. F...

  17. Response of the Andean diversity panel to root rot in a root rot nursery in Puerto Rico

    Science.gov (United States)

    The Andean Diversity Panel (ADP) was evaluated under low-fertility and root rot conditions in two trials conducted in 2013 and 2015 in Isabela, Puerto Rico. About 246 ADP lines were evaluated in the root rot nursery with root rot and stem diseases caused predominantly by Fusarium solani, which cause...

  18. MANAGEMENT OF ROOT ROT IN AVOCADO TREES

    Directory of Open Access Journals (Sweden)

    SIMONE RODRIGUES DA SILVA

    Full Text Available ABSTRACT Root rot (Phytophthora cinnamomi Rands is one of the most restrictive factors to avocado growing in main producing regions worldwide. In Brazil, scientific reports on the effectiveness of control methods are scarce. The objective of this study was to evaluate the efficiency of gypsum applications and dolomitic limestone to the soil and potassium phosphite sprays in controlling this disease in ‘Hass’ avocado, grown without irrigation. The application of dolomitic limestone or gypsum alone is not effective to recover plants affected by root rot. The application of potassium phosphite, combined or not with dolomitic lime or gypsum enables the partial recovery ‘Hass’ avocado plants affected by the disease.

  19. The influence of root rot incidence on cassava genotype on ...

    African Journals Online (AJOL)

    In Nigeria cassava root rot causes serious yield losses in cassava tuber production every year. However, the influence of root rot incidence on cassava genotype at harvest on consumers' acceptability of the gari produced from it has not been studied. A sensory evaluation was conducted on gari processed from the tuberous ...

  20. Pathological and rhizospherical studies on root-rot disease of ...

    African Journals Online (AJOL)

    AJB SERVER

    2007-02-05

    Feb 5, 2007 ... Rhizoctonia solani root-rot aggressive pathogens to squash on media containing culture of Trichoderma ..... The bacteriology of root region of cat ... (2004): Comparison of the behavior of a transformed hygromycin resistant ...

  1. 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.

  2. Comparing methods for inducing root rot of Rhododendron with Phytophthora cinnamomi and P. plurivora

    Science.gov (United States)

    Root rot, caused by Phytophthora cinnamomi and P. plurivora in containerized Rhododendron, can cause significant losses in the nursery industry. Studies commonly use a 48 h flooding event to stimulate root infection. While flooding rarely occurs in container nurseries, plants may sit in a shallow pu...

  3. 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

  4. Antagonistic Effect of Native Bacillus Isolates against Black Root Rot ...

    African Journals Online (AJOL)

    Faba bean (Vicia faba L.) is one of the most important pulse crops grown in eastern Africa. Black root rot (Fusarium solani) is known to cause great yield losses in faba bean, especially in the highlands of Ethiopia. The objective of this study was to evaluate the biological control ability of native Bacillus species on the basis of ...

  5. Resistance to Fusarium dry root rot disease in cassava accessions

    Directory of Open Access Journals (Sweden)

    Saulo Alves Santos de Oliveira

    2013-10-01

    Full Text Available The objective of this work was to identify sources of resistance to dry root rot induced by Fusarium sp. in cassava accessions. A macroconidial suspension (20 µL of 11 Fusarium sp. isolates was inoculated in cassava roots, from 353 acessions plus seven commercial varieties. Ten days after inoculation, the total area colonized by the pathogen on the root pulp was evaluated by digital image analysis. Cluster analysis revealed the presence of five groups regarding resistance. The root lesion areas ranged from 18.28 to 1,096.07 mm² for the accessions BGM 1518 and BGM 556, respectively. The genotypes BGM 1042, BGM 1552, BGM 1586, BGM 1598, and BGM 1692 present the best agronomical traits.

  6. Fungicides reduce Rhododendron root rot and mortality caused by Phytophthora cinnamomi, but not by P. plurivora

    Science.gov (United States)

    Rhododendron root rot, caused by several Phytophthora species, can cause devastating losses in nursery-grown plants. Most research on chemical control of root rot has focused on Phytophthora cinnamomi. However, it is unknown whether treatments recommended for P. cinnamomi are also effective for othe...

  7. Nonchemical, cultural management strategies to suppress phytophthora root rot in northern highbush blueberry

    Science.gov (United States)

    Phytophthora cinnamomi causes root rot of highbush blueberry and decreases plant growth, yield, and profitability for growers. Fungicides can suppress root rot, but cannot be used in certified organic production systems and fungicide resistance may develop. Alternative, non-chemical, cultural manag...

  8. Pathogenicity and genetic diversity of Fusarium oxysporum causing soybean root rot in northeast China

    Science.gov (United States)

    Soybean is an important edible legume cultivated around the world. However, soybean production is seriously impacted by the widespread occurrence of root rot disease. In this study, genetic diversity and pathogenicity of Fusarium oxysporum associated with root rot of soybean in Heilongjiang province...

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

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    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.

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

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    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.

  11. Efficacy of four plant extracts in the control of root rot disease of ...

    African Journals Online (AJOL)

    Garcinia cola) and neem (Azadirachta indica) extracts in the control of root rot of cowpea caused by Pythium aphanidermatum was carried out in vitro and in the field (in vivo). They were evaluated for their antifungal activity over P.

  12. Suppression of crown and root rot of wheat by the rhizobacterium Paenibacillus polymyxa

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    Lamia LOUNACI

    2017-01-01

    Full Text Available A seedling bioassay was developed for screening a wheat root-associated rhizobacterial strain of Paenibacillus polymyxa for ability to suppress crown and root rot pathogens of wheat. The primary aim was to evaluate the ability of P. polymyxa to suppress Fusarium graminearum, F. culmorum, F. verticillioides and Microdochium nivale, the fungal pathogens responsible for Fusarium crown and root rot and head blight of wheat in Algeria. Bioassays conducted under controlled conditions indicated that seed treatments with P. polymyxa strain SGK2 significantly reduced disease symptoms caused by all four fungal pathogens. Plant growth promotion (increased shoot and root dry weights, however, depended on the pathogen tested. Our results indicate that seed treatments with a biocontrol agent could be an additional strategy for management of wheat crown and root rot pathogens.

  13. Etiology and epidemiology of Pythium root rot in hydroponic crops: current knowledge and perspectives

    Directory of Open Access Journals (Sweden)

    John Clifford Sutton

    2006-09-01

    Full Text Available The etiology and epidemiology of Pythium root rot in hydroponically-grown crops are reviewed with emphasis on knowledge and concepts considered important for managing the disease in commercial greenhouses. Pythium root rot continually threatens the productivity of numerous kinds of crops in hydroponic systems around the world including cucumber, tomato, sweet pepper, spinach, lettuce, nasturtium, arugula, rose, and chrysanthemum. Principal causal agents include Pythium aphanidermatum, Pythium dissotocum, members of Pythium group F, and Pythium ultimum var. ultimum. Perspectives are given of sources of initial inoculum of Pythium spp. in hydroponic systems, of infection and colonization of roots by the pathogens, symptom development and inoculum production in host roots, and inoculum dispersal in nutrient solutions. Recent findings that a specific elicitor produced by P. aphanidermatum may trigger necrosis (browning of the roots and the transition from biotrophic to necrotrophic infection are considered. Effects on root rot epidemics of host factors (disease susceptibility, phenological growth stage, root exudates and phenolic substances, the root environment (rooting media, concentrations of dissolved oxygen and phenolic substances in the nutrient solution, microbial communities and temperature and human interferences (cropping practices and control measures are reviewed. Recent findings on predisposition of roots to Pythium attack by environmental stress factors are highlighted. The commonly minor impact on epidemics of measures to disinfest nutrient solution as it recirculates outside the crop is contrasted with the impact of treatments that suppress Pythium in the roots and root zone of the crop. New discoveries that infection of roots by P. aphanidermatum markedly slows the increase in leaf area and whole-plant carbon gain without significant effect on the efficiency of photosynthesis per unit area of leaf are noted. The platform of

  14. First report of root rot of cowpea caused by Fusarium equiseti in Georgia in the United States

    Science.gov (United States)

    Root rot was observed on cowpea in Tift County, Georgia, in May of 2015. The disease occurred on approximately 10% of cowpea plants in 2 fields (2 ha). Symptoms appeared as sunken reddish brown lesions on roots and stems under the soil line, secondary roots became dark brown and rotted, and infected...

  15. The influence of root rot incidence on cassava genotype on ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-16

    Nov 16, 2009 ... model statistical procedures with the SAS system for windows. Comparisons ... significantly different at probability 0.05%. The results of this ... Due to inefficient harvesting, packaging ... from rot for gari processing. Where there ...

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

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    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.

  17. Phytophthora Root and Crown Rot on Apples in Bulgaria

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    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. root rot disease of five fruit tree seedlings in the nursery

    African Journals Online (AJOL)

    KAMALDEEN

    on them. Our experience in the nursery in Port Harcourt had been that many tree species of the tropical region are susceptible to root rot diseases of fungal origin. The fungal invasion of the succulent root tissues causes the young tree seedlings to dieback; their leaves becomes discoloured, wilted and eventually dead.

  19. Root rot symptoms in sugar beet lines caused by Fusarium oxysporum f. sp. betae

    Science.gov (United States)

    The soil-borne fungus Fusarium oxysporum may cause both Fusarium yellows and Fusarium root rot diseases with severe yield losses in cultivated sugar beet worldwide. These two diseases cause similar foliar symptoms but different root response and have been proposed to be due to two distinct F. oxyspo...

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

    Science.gov (United States)

    Hassan, Naglaa; Shimizu, Masafumi

    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 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

  1. 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.

  2. Attempts to control Fusarium root rot of bean by seed dressing.

    Science.gov (United States)

    Gilardi, G; Baudino, M; Gullino, M L; Garibaldi, A

    2008-01-01

    In summer 2006, a root rot caused by Fusarium oxysporum was observed in commercial farms on common bean (Phaseolus vulgaris) on the cv Billò and Borlotto. A study was undertaken in order to evaluate the efficacy of different biological control agents applied as seed dressing. In the presence of a medium-high disease incidence, among the biocontrol agents tested, Trichoderma harzianum T 22, Bacillus subtilis QST 713, followed by Pseudomonas chlororaphis, provided generally the best control. Their efficacy was also consistent in the different trials. Also the mixture of T. harzianum + T. viride provide a good disease control. Streptomyces griseoviridis and the 3 strains of Fusarim oxysporum, although less effective, provided a partial control of the disease. The fungicide mancozeb provided only a partial disease control.

  3. [Research progress in root rot diseases of Chinese herbal medicine and control strategy by antagonistic microorganisms].

    Science.gov (United States)

    Gao, Fen; Ren, Xiao-xia; Wang, Meng-liang; Qin, Xue-mei

    2015-11-01

    In recent years, root rot diseases of Chinese herbal medicine have been posing grave threat to the development of the traditional Chinese medicine industry. This article presents a review on the occurring situation of the root rot disease, including the occurrence of the disease, the diversity of the pathogens, the regional difference in dominant pathogens,and the complexity of symptoms and a survey of the progress in bio-control of the disease using antagonistic microorganisms. The paper also discusses the existing problems and future prospects in the research.

  4. rDNA-based characterization of a new binucleate Rhizoctonia spp. causing root rot on kale in Brazil

    NARCIS (Netherlands)

    Kuramae, E.E.; Buzeto, A.L.; Nakatani, A.K.; Souza, N.L.

    2007-01-01

    In this paper we present the first report of the occurrence of a binucleate Rhizoctonia spp. causing hypocotyl and root rot in kale in Brazil. Rhizoctonia spp. were isolated from kale (Brassica oleracea var. acephala) with symptoms of hypocotyl and root rot. The isolates, characterized as binucleate

  5. Armillaria root rot of tea in Kenya : characterization of the pathogen and approaches to disease management

    NARCIS (Netherlands)

    Otieno, W.

    2002-01-01

    The rare occurrence of basidiomata and rhizomorphs constrains diagnosis of Armillaria root rot and identification of Armillaria species in Africa. This has had a negative impact on taxonomic research on the genus Armillaria in the continent, where the

  6. Root Rot Disease of Five Fruit Tree Seedlings in the Nursery ...

    African Journals Online (AJOL)

    The incidence of root rot disease in the nursery of Chrysophyllum albidun Dacryodes edulis, persea Americana, Irvingia gabonensis and Annona muricala was assessed. Ten fungal pathogen were isolated using serial dilution and pathogenicity tests were carried out on the 5 fruit trees with the 10 isolated fungi. The 5 fruit ...

  7. Mechanisms of qualitative and quantitative resistance to Aphanomyces root rot in alfalfa

    Science.gov (United States)

    Aphanomyces root rot (ARR), caused by Aphanomyces euteiches, is one of the most important diseases of alfalfa (Medicago sativa) in the United States. Two races of the pathogen are currently recognized. Most modern alfalfa cultivars have high levels of resistance to race 1 but few cultivars have resi...

  8. 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

  9. Plectosphaerella species associated with root and collar rots of horticultural crops in southern Italy

    NARCIS (Netherlands)

    Carlucci, A.; Raimondo, M.L.; Santos, J.; Phillips, A.J.L.

    2012-01-01

    Plectosphaerella cucumerina, most frequently encountered in its Plectosporium state, is well known as a pathogen of several plant species causing fruit, root and collar rot, and collapse. It is considered to pose a serious threat to melon (Cucumis melo) production in Italy. In the present study, an

  10. Seventeen years of research on genetics of resistance to Aphanomyces root rot of pea

    Science.gov (United States)

    Aphanomyces root rot, caused by the oomycete Aphanomyces euteiches, is a major soil borne disease of pea in many countries. Genetic resistance is considered to be a main way to control the disease. Since 2000, INRA has engaged a long-term research program to study genetic resistance to A. euteiches ...

  11. Occurrence of the root-rot pathogen, Fusarium commune, in midwestern and western United States

    Science.gov (United States)

    J. E. Stewart; R. K. Dumroese; N. B. Klopfenstein; M. -S. Kim

    2012-01-01

    Fusarium commune can cause damping-off and root rot of conifer seedlings in forest nurseries. The pathogen is only reported in Oregon, Idaho, and Washington within United States. Fusarium isolates were collected from midwestern and western United States to determine occurrence of this pathogen. DNA sequences of mitochondrial small subunit gene were used to identify F....

  12. A single dominant Ganoderma species is responsible for root rot of ...

    African Journals Online (AJOL)

    Ganoderma root rot is the most serious disease affecting commercially planted Acacia mangium in plantations in Indonesia. Numerous Ganoderma spp. have been recorded from diseased trees of this species and to a lesser extent Eucalyptus, causing confusion regarding the primary cause of the disease. In this study, a ...

  13. Creating prescription maps from satellite imagery for site-specific management of cotton root rot

    Science.gov (United States)

    Cotton root rot is a century-old cotton disease that can now be controlled with Topguard Terra Fungicide. However, as this disease tends to occur in the same general areas within fields year after year, site-specific treatment can be more effective and economical. The objective of this study was to ...

  14. 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...

  15. Site-specific management of cotton root rot using historical remote sensing imagery

    Science.gov (United States)

    Cotton root rot can now be effectively controlled with Topguard Terra Fungicide, but site-specific application of the fungicide can greatly reduce treatment cost as only portions of the field are infested with the disease. The overall goal of this three-year project was to demonstrate how to use his...

  16. Using airborne imagery to monitor cotton root rot infection before and after fungicide treatment

    Science.gov (United States)

    Cotton root rot is a severe soilborne disease that has affected cotton production for over a century. Recent research has shown that a commercial fungicide, flutriafol, has potential for the control of this disease. To effectively and economically control this disease, it is necessary to identify in...

  17. Combining fuzzy set theory and nonlinear stretching enhancement for unsupervised classification of cotton root rot

    Science.gov (United States)

    Cotton root rot is a destructive disease affecting cotton production. Accurate identification of infected areas within fields is useful for cost-effective control of the disease. The uncertainties caused by various infection stages and newly infected plants make it difficult to achieve accurate clas...

  18. Role of mungbean root nodule associated fluorescent Pseudomonas and rhizobia in suppressing the root rotting fungi and root knot nematodes in chickpea (Cicer arietinum L.)

    International Nuclear Information System (INIS)

    Noreen, R.; Shafique, A.; Haque, S.E.; Ali, S.A.

    2016-01-01

    Three isolates each of fluorescent Pseudomonas (NAFP-19, NAFP-31 and NAFP-32) and rhizobia (NFB- 103, NFB-107 and NFB-109) which were originally isolated from root nodules of mungbean (Vigna radiata) showed significant biocontrol activity in the screen house and under field condition, against root rotting fungi viz., Macrophomina phaseolina, Fusarium solani, F. oxysporum and Rhizoctonia solani evaluated on chickpea. Biocontrol potential of these isolates was also evaluated against Meloidogyne incognita, the root knot nematode. Application of Pseudomonas and rhizobial isolates as a soil drench, separately or mixed significantly reduced root rot disease under screen house and field conditions. Nematode penetration in roots was also found significantly less in rhizobia or Pseudomonas treatments used separately or mixed as compared to control. Fluorescent Pseudomonas treated plants produced greater number of nodules per plant than control plants and about equal to rhizobia treated plants, indicating that root nodule associated fluorescent Pseudomonas enhance root nodulation. (author)

  19. 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.

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

    International Nuclear Information System (INIS)

    El-Batal, A.I.; Fathy, R.M.; Ismail, A.A.; Mubark, H.M.; Mahmoud, Y.A.

    2011-01-01

    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

  1. 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.

  2. 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...

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

    OpenAIRE

    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-indus...

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

    Science.gov (United States)

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

    2014-01-01

    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

  5. Spatial Distribution of Root and Crown Rot Fungi Associated With Winter Wheat in the North China Plain and Its Relationship With Climate Variables

    Science.gov (United States)

    Xu, Fei; Yang, Gongqiang; Wang, Junmei; Song, Yuli; Liu, Lulu; Zhao, Kai; Li, Yahong; Han, Zihang

    2018-01-01

    The distribution frequency of pathogenic fungi associated with root and crown rot of winter wheat (Triticum aestivum) from 104 fields in the North China Plain was determined during the period from 2013 to 2016. The four most important species identified were Bipolaris sorokiniana (24.0% from roots; 33.7% from stems), Fusarium pseudograminearum (14.9% from roots; 27.8% from stems), Rhizoctonia cerealis (1.7% from roots; 4.4% from stems), and Gaeumannomyces graminis var. tritici (9.8% from roots; 4.4% from stems). We observed that the recovered species varied with the agronomic zone. Fusarium pseudograminearum was predominant in regions 1 and 3, whereas F. graminearum, F. acuminatum, and R. cerealis were predominant in regions 2 and 4. The incidence of F. pseudograminearum and R. cerealis was significantly different between regions 1 and 4, while no significant association was found in the distribution of the other species and the agronomic zones. A negative correlation between the frequency of occurrence of F. pseudograminearum and mean annual precipitation during 2013–2016 (r = −0.71; P wheat, two or more root and crown rot species were isolated. The coexistence of Fusarium spp. and B. sorokiniana in one field (65.4%) or in individual plants (11.6%) was more common than for the other species combinations. Moreover, this is the first report on the association between F. sinensis and root and crown rot of wheat. Our results would be useful in the framing guidelines for the management of root and crown rot fungi in wheat in different agronomic zones of the North China Plain. PMID:29887840

  6. Pathological and rhizospherical studies on root-rot disease of ...

    African Journals Online (AJOL)

    Isolations from diseased squash roots revealed the presence of Alternaria tenuis, Aspergillus niger, Fusarium oxysporum, F. solani and Rhizoctonia solani. The last two fungi were more frequent than any of the other fungi. Pathogenicity tests proved that squash plants were highly vulnerable to attack by Fusarium solani and ...

  7. The Growth of Root Rot Disease on Pepper Seed Applied by Trichoderma Harzianum Inoculum

    Directory of Open Access Journals (Sweden)

    S. Sofian

    2013-06-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Root rot disease on pepper caused by Phytophthora capsici is one of the most important diseases on pepper. The using of antagonistic fungus of Trichoderma harzianum as a biological control agent of the pathogen is one of the important alternatives in controlling P. capsici without causing negative effects on the environment. The objectives of the research were to study about the ability of T. harzianum inoculum application in inhibiting the development of root-rot disease, influenced the growth of pepper seed, to studythe effective length time application of T. harzianum inoculum in inhibiting the development of root rot disease, and increased the growth of pepper seedlings. This research was arranged in a completely randomized design, with five treatments of length time application of T. harzianum inoculum i.e. control treatment without applicationtime of T. harzianum inoculum (K, application time of T. harzianum inoculum for 0 week (S0, application time of T. harzianum inoculum for 1 week (S1, application time of T. harzianum inoculum for two weeks (S2, application time of T. harzianum inoculum for three weeks (S3, and application time of T. harzianum inoculum for 4 weeks (S4 before planting. Each treatment was repeated15 times. The observed parameterswere disease percentage, the inhibition of antagonistic fungus, disease infection rate, plant height, number of leaves, wet and dry weight of plant, stem and leaves on pepper seed, and P. capsici population density. The result showed that application time of T. harzianum inoculumfor 4 weeks (S4 before planting is the most effective time in inhibiting the development of root rot disease than the other treatment sand also had significant effect on increasing the growth of pepper seed. The antagonism test showed that T. harzianum could inhibit P. capsiciin vitro. This result proves that application time of T. harzianum inoculums

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

    International Nuclear Information System (INIS)

    Hanif, A.; Dawar, S.

    2015-01-01

    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)

  9. 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.

  10. 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

  11. Management of chili pepper root rot and wilt (caused by Phytophthora nicotianae by grafting onto resistant rootstock

    Directory of Open Access Journals (Sweden)

    Mourad SAADOUN

    2013-05-01

    Full Text Available Root rot and plant wilting caused by Phytophthora nicotianae is a severe disease of chili pepper (Capsicum annuum L. in open fields and under greenhouse production in Tunisia. Chili pepper grafting for disease manage- ment is attracting increased interest in recent years. Using the tube grafting technique, different compatible scion/rootstock combinations were obtained with the wild-type pepper SCM334 and the local chili pepper cultivars ‘Beldi’ and ‘Baker’. SCM334 was resistant to P. nicotianae, while the cultivars Beldi and Baker were susceptible. Plant inoculations were performed with P. nicotianae zoospores, and severity of root rot was rated 30 days post- inoculation using a 0 (healthy plant to 5 (dead plant severity score. On SCM334 rootstock and with ‘Beldi’ or ‘Baker’ scions, the intensity of root rot was very low (mean score 0.1–0.2 and plants were healthy. However, with Baker or Beldi rootstocks and SCM334 scions, root rot was severe (mean score 3.1–4.6, leading to high numbers of wilting and dead plants. This severe root rot was similar to that observed on non-grafted plants of ‘Baker’ and ‘Beldi’ inoculated with the pathogen. Under greenhouse conditions, measurements of agronomic characters indicated non-consistent improvement of these features on the scion cultivar when SCM334 was the rootstock. Since plant foliage is not attacked by this pathogen, these results show that susceptible chili pepper scions grafted onto SCM334 rootstocks could be used for root rot management and improvement of pepper yields in P. nicotianae infested soils.

  12. A combination of biocontrol agents improves the management of dry root rot (Macrophomina phaseolina in greengram

    Directory of Open Access Journals (Sweden)

    R. Thilagavathi

    2007-08-01

    Full Text Available The biocontrol agents Trichoderma viride (strains Tv1 and Tv13, Pseudomonas fluorescens (Pf1 and Py15 and Bacillus subtilis (Bs16 were tested individually and in combination for their effectiveness against root rot of greengram caused by Macrophomina phaseolina. As regards the compatibility of the biocontrol agents with each other, T. viride strains were not compatible with B. subtilis (Bs16, but P. fluorescens strains were compatible with B. subtilis and T. viride. Of the biocontrol agents tested in vitro against M. phaseolina, combinations of P. fluorescens+T. viride (Pf1+Tv1, Pf1+Tv13 and Py15+Tv1 inhibited mycelial growth of the pathogen and they also promoted the growth of the greengram seedlings. A combination of Pf1+Tv1 was most effective in reducing root rot incidence under glass-house and field conditions as compared with other single or combined treatments or the untreated control. The activity of the defense-related enzymes peroxidase, polyphenol oxidase and phenyl alanine ammonia lyase was significantly greater in greengram plants treated with a talc based formulation containing Pf1+Tv1 followed by Pf1+Tv13 and Py15+Tv1, than in plants receiving other treatments or the untreated control. Moreover, a combination of Pf1+Tv1 followed by Pf1+Tv13 and Py15+Tv1 significantly increased yield under glass house and field conditions.

  13. The preventive Control of White Root Rot Disease in Small Holder Rubber Plantation Using Botanical, Biological and Chemical Agents

    Directory of Open Access Journals (Sweden)

    Joko Prasetyo

    2014-03-01

    Full Text Available The preventive control of white root rot disease in small holder plantation using botanical, biological, and chemical agents. A field and laboratory experiment were conducted from June 2008 to December 2009 in Panumangan, Tulang Bawang - Lampung. The  field experiment was intended to evaluate the effect of  botanical plants (Alpinia galanga, Sansiviera auranthii, and Marantha arundinacea, biological agents (organic matter and Trichoderma spp., and chemical agents (lime and natural sulphur on the incidence of white root rot disease and population of some soil microbes. The laboratory experiment was conducted  to observe the mechanism of botanical agents  in controlling white root rot disease. In the field experiment, the treatments were applied  in the experimental plot with cassava plant infection as the indicator. The variables  examined were the incidence of  white root rot and population of soil microbes. In the laboratory experiment, culture of R. microporus was grown in PDA containing root exudate of the antagonistic plant (botanical agent. The variable examined was colony diameter of R. microporus growing in the PDA plates. The results of the  field experiment  showed that planting of the botanical agents, and application of Trichoderma spp., as well as natural sulphur, decreased the incidence of white root rot disease. The effectiveness of M. arundinacea and Trichoderma spp. was comparable to natural  sulphur. The laboratory experiment showed only root exudate of  A. galanga and  S. auranthii that were significantly inhibit the growth of R. microporus.

  14. Spatial Distribution of Root and Crown Rot Fungi Associated With Winter Wheat in the North China Plain and Its Relationship With Climate Variables

    Directory of Open Access Journals (Sweden)

    Fei Xu

    2018-05-01

    Full Text Available The distribution frequency of pathogenic fungi associated with root and crown rot of winter wheat (Triticum aestivum from 104 fields in the North China Plain was determined during the period from 2013 to 2016. The four most important species identified were Bipolaris sorokiniana (24.0% from roots; 33.7% from stems, Fusarium pseudograminearum (14.9% from roots; 27.8% from stems, Rhizoctonia cerealis (1.7% from roots; 4.4% from stems, and Gaeumannomyces graminis var. tritici (9.8% from roots; 4.4% from stems. We observed that the recovered species varied with the agronomic zone. Fusarium pseudograminearum was predominant in regions 1 and 3, whereas F. graminearum, F. acuminatum, and R. cerealis were predominant in regions 2 and 4. The incidence of F. pseudograminearum and R. cerealis was significantly different between regions 1 and 4, while no significant association was found in the distribution of the other species and the agronomic zones. A negative correlation between the frequency of occurrence of F. pseudograminearum and mean annual precipitation during 2013–2016 (r = −0.71; P < 0.01 in the North China Plain and a positive correlation between the mean annual precipitation during 2013–2016 and the frequency of occurrence of F. asiaticum (r = 0.74; P < 0.01 were observed. Several Fusarium species were also found with low frequencies of ~2.1%−3.4 % (F. graminearum, F. acuminatum, and F. sinensis and ~0.1%−1.3% (F. equiseti, F. oxysporum, F. proliferatum, F. culmorum, F. avenaceum, and F. asiaticum. In more than 93% of the fields, from the root and crown tissues of wheat, two or more root and crown rot species were isolated. The coexistence of Fusarium spp. and B. sorokiniana in one field (65.4% or in individual plants (11.6% was more common than for the other species combinations. Moreover, this is the first report on the association between F. sinensis and root and crown rot of wheat. Our results would be useful in the framing

  15. Site-specific management of cotton root rot using airborne and satellite imagery and variable rate technology

    Science.gov (United States)

    Cotton root rot is a serious cotton disease that can now be effectively controlled with Topguard Terra Fungicide. However, its recurrence in the same areas year after year makes fungicide application only to infested areas more effective and economical than uniform application. Base on 17 years of r...

  16. Effect of cultural practices and fungicide treatments on the severity of Phytophthora root rot of blueberries grown in Mississippi

    Science.gov (United States)

    Phytophthora root rot is an important disease of blueberries, especially those grown in areas with poor drainage. Reliable cultural and chemical management strategies are needed for control of this disease. Two studies were conducted to evaluate the effects of cultural practices and fungicide treat...

  17. Occurrence of the root-rot pathogen, Fusarium commune, in forest nurseries of the midwestern and western United States

    Science.gov (United States)

    Mee-Sook Kim; Jane E. Stewart; R. Kasten Dumroese; Ned B. Klopfenstein

    2012-01-01

    Fusarium commune can cause damping-off and root rot of conifer seedlings in forest nurseries, and this pathogen has been previously reported from Oregon, Idaho, and Washington, USA. We collected Fusarium isolates from additional nurseries in the midwestern and western USA to more fully determine occurrence of this pathogen. We used DNA sequences of the mitochondrial...

  18. 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

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

    International Nuclear Information System (INIS)

    Nafees, M.; Ahmad, I.; Ahmad, S.; Anwar, R.; Maryyam, A.; Hussnain, R.R.

    2013-01-01

    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)

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

    International Nuclear Information System (INIS)

    Ikram, N.; Dawar, S.; Zaki, M.J.; Abass, Z.

    2010-01-01

    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)

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

    Directory of Open Access Journals (Sweden)

    S. Neuhauser

    2009-05-01

    Full Text Available 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 purifi cation 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 specifi city 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-specifi c primers in combination with the DNA extraction method for soil was high: as little as 100 fg μl-1 R.-subterranea-DNA was suffi cient for a detection in soil samples and plant material. Given that specifi c primers are available, the presented method will also allow quick and large-scale testing for other root pathogens.

  2. Biological control of Fusarium solani f. sp. phaseoli the causal agent of root rot of bean using Bacillus subtilis CA32 and Trichoderma harzianum RU01

    Directory of Open Access Journals (Sweden)

    Saman Abeysinghe

    2007-09-01

    Full Text Available Root rot, caused by Fusarium solani f. sp. phaseoli, is one of the main root diseases impacting production of common bean in Sri Lanka. Rhizobacteria were screened in dual Petri plate assays to select antagonistic strains against F. solani f. sp. phaseoli. B. subtilis CA32 effectively antagonized the pathogen. T. harzianum RU01 also showed the antagonistic activity. The efficacy of the B. subtilis CA32 and the T. harzianum RU01 were tested in greenhouse pot experiments against F. solani f. sp. phaseoli. Seed bacterization with B. subtilis CA32 and T. harzianum RU01 significantly protected bean seedlings from F. solani f. sp. phaseoli compared to the untreated control plants. Plant protection was more pronounced in T. harzianum RU01 treated plants than bacterized plants. Enhanced root growth was observed only T. harzianum RU01 treated plants, suggesting that the biotic modifications of the mycorrhizosphere as a result of colonization with T. harzianum RU01.

  3. Somaclonal variation of sugar beet resistant to pathogenic root rot Fusarium oxysporum var. orthoceras

    Directory of Open Access Journals (Sweden)

    Urazaliev Kairat

    2013-01-01

    Full Text Available Sugar beet (Beta vulgaris L. - one of the most important crop in the world. In Kazakhstan, it is a traditional and major source of domestic sugar. The industry of cultivation and production of sugar beet is one of the priority areas of agricultural development of the country. In this paper, we studied the regeneration ability of different genotypes of sugar beet explants on selective media with the culture filtrate of the pathogen fungus F. oxysporum var. orthoceras. From the roots and shoots of sugar beet the pathogen Fusarium root rot was isolated. Was obtained pure cultures of the isolated pathogen. As a result, of morphological and cultural descriptions, as well as microbiological analysis it was revealed that the isolated pathogen is Fusarium Oxysporum. The results showed the pathogenicity of the fungus. For regeneration in vitro of the sugar beet genotypes resistant to the pathogen the culture media was optimized to the culture filtrate of the fungus F. oxysporum var. orthoceras. The frequency of shoot regeneration, depending on the genotype, was 1,0-12,5 %. On these explants the multiple shoot formations were observed.

  4. Evaluation of biocontrol potential of epiphytic fluorescent pseudomonas as associated with healthy fruits and vegetables against root rot and root knot pathogens of mungbean

    International Nuclear Information System (INIS)

    Habiba, A.; Noreen, R.; Ali, S. A.; Sultana, V.; Ara, J.

    2016-01-01

    Endophytic and rhizospheric fluorescent Pseudomonas have widely been used as biological control agents against soilborne plant pathogens. In this study, fifteen epiphytic fluorescent Pseudomonas isolated from the surfaces of citrus (grapefruit, orange and lemon) melon and tomato fruits were characterized for their in vitro activity against root rotting fungi viz., Macrophomina phaseolina, Fusarium solani, F. oxysporum and Rhizoctonia solani and nematicidal activity against the second stage juveniles of Meloidogyne javanica. Out of fifteen Pseudomonas isolates HAB-16, HAB-1 and HAB-25 inhibited the growth of all the test fungi and showed maximum nematicidal activity against second stage juvenile of M. javanica. Based on their effective in vitro activity nine epiphytic fluorescent Pseudomonas were evaluated for their growth promoting ability and biocontrol activity in screen house on mungbean. Pseudomonas isolates (HAB-13, HAB-2, HAB-4, HAB-1, HAB-14, HAB-9, HAB-7 and HAB-25) used as soil drench greatly reduced the root rot-root knot infection and thereby enhanced plant growth, root nodulation and yield in mungbean. Besides, rhizospheric and endophytic, epiphytic fluorescent Pseudomonas associated with healthy fruits may be used as biocontrol agent against root rotting fungi, besides, using for the mangemnet of postharvest diseases. (author)

  5. Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

    Directory of Open Access Journals (Sweden)

    You-Kun Zheng

    2017-07-01

    Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

  6. Composts containing fluorescent pseudomonads suppress fusarium root and stem rot development on greenhouse cucumber.

    Science.gov (United States)

    Bradley, Geoffrey G; Punja, Zamir K

    2010-11-01

    Three composts (Ball, dairy, and greenhouse) were tested for the ability to suppress the development of Fusarium root and stem rot (caused by Fusarium oxysporum f. sp. radicis-cucumerinum) on greenhouse cucumber. Dairy and greenhouse composts significantly reduced disease severity (P = 0.05), while Ball compost had no effect. Assessment of total culturable microbes in the composts showed a positive relationship between disease suppressive ability and total population levels of pseudomonads. In vitro antagonism assays between compost-isolated bacterial strains and the pathogen showed that strains of Pseudomonas aeruginosa exhibited the greatest antagonism. In growth room trials, strains of P. aeruginosa and nonantagonistic Pseudomonas maculicola, plus 2 biocontrol strains of Pseudomonas fluorescens, were tested for their ability to reduce (i) survival of F. oxysporum, (ii) colonization of plants by the pathogen, and (iii) disease severity. Cucumber seedlings grown in compost receiving P. aeruginosa and P. fluorescens had reduced disease severity index scores after 8 weeks compared with control plants without bacteria. Internal stem colonization by F. oxysporum was significantly reduced by P. aeruginosa. The bacteria colonized plant roots at 1.9 × 10(6) ± 0.73 × 10(6) CFU·(g root tissue)-1 and survival was >107 CFU·(g compost)-1 after 6 weeks. The locus for 2,4-diacetylphloroglucinol production was detected by Southern blot analysis and confirmed by PCR. The production of the antibiotic 2,4-diacetylphloroglucinol in liquid culture by P. aeruginosa was confirmed by thin layer chromatography. These results demonstrate that composts containing antibiotic-producing P. aeruginosa have the potential to suppress diseases caused by Fusarium species.

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

    International Nuclear Information System (INIS)

    Rasha Mohammed Fathy El- Said, R.M.F.

    2012-01-01

    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

  8. Studies on in vitro induction mutation for wheat mutant of resistance to root rot and its resistance mechanism

    International Nuclear Information System (INIS)

    Sun Guangzu

    1992-06-01

    The screening wheat mutant which has the resistance to root rot was completed in 37 varieties by in vitro induction mutation method. The effect of irradiation on in vitro culture of different wheat explants and the effectiveness of screening rude toxin were studied. Two wheat mutants, RB500 and RB501, which have the resistance to root rot, were obtained. Changes of the ultrastructure and defensive enzymes (SOD, ROD and PAL) were investigated by using mutants and parent under the action of rude toxin. The results showed that the rude toxin could induce changes of enzyme activity, isoenzyme pattern and ultrastructure of the mitochondria and chloroplast. These change correspond to their ability of resistance to disease. The mutant under the action of toxin has the ability to increase the defensive enzyme activity and to reduce the damage of cell membrane system that would result in resistance increasing

  9. Wheat protection from root rot caused by fusarium culmorum using silver nanoparticles

    International Nuclear Information System (INIS)

    Rashed, A.O.M.; Mohamed, A.A.R.; Abobakr, M.M.

    2016-01-01

    Nanomaterials have a positive impact on agriculture. Silver nanoparticles were used to enhance seed germination, plant growth, and as antimicrobial agents to control plant diseases. In the present study, the effectiveness of silver nanoparticles on seed germination of wheat, growth parameters, and control of root rot disease caused by Fusarium culmorum were examined. Three different concentrations (10, 20, and 40 mg/l) were used. Exposure to AgNPs had no significant effects on the seed germination at 10 mg/l and 20 mg/l while at 40 mg/l significant effects were observed compared to that in the control (untreated). Germination was highest (86 percent) after exposure to 20 mg/l of AgNPs. AgNPs, at all concentrations tested, had significant effects on the pre-emergence, post-emergence and survival as compared to the control (infected and untreated with AgNPs); the highest effects were observed after exposure to 40 mg/l of AgNPs (15, 10, and 75 percent respectively). Additionally, our results indicate that plant height, fresh weight, and dry weight were significantly increased at 10 mg/l (23.4 cm, 6 g, and 1.45 g), and 20 mg/l (27.3 cm, 7.5 g, and 1.98 g) respectively, compared with that of the control. However, higher concentration (40 mg/l) of AgNPs decreased the growth parameters. (author)

  10. [Antagonism of Trichoderma spp. to fungi caused root rot of Sophora tonkinensis].

    Science.gov (United States)

    Qin, Liu-yan; Jiang, Ni; Tang, Mei-qiong; Miao, Jian-hua; Li, Lin-xuan

    2011-04-01

    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. 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. 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 inhibition indexes were both reached class I. The inhibition index and inhibition rate of K1 was respectively 46.36% and class IV. The Trichoderma spp. could cause S9 mycelium to appear some phenomenon just like fracture, constriction reduced, digestion, etc. which were observed under the microscope. Trichoderma harsianum and Trichoderma viride showed the further develop prospects in the fight against soil-borne disease on Chinese herbal medicines.

  11. Short Rotations in Forest Plantations Accelerate Virulence Evolution in Root-Rot Pathogenic Fungi

    Directory of Open Access Journals (Sweden)

    Jean-Paul Soularue

    2017-06-01

    Full Text Available As disease outbreaks in forest plantations are causing concern worldwide, a clear understanding of the influence of silvicultural practices on the development of epidemics is still lacking. Importantly, silvicultural practices are likely to simultaneously affect epidemiological and evolutionary dynamics of pathogen populations. We propose a genetically explicit and individual-based model of virulence evolution in a root-rot pathogenic fungus spreading across forest landscapes, taking the Armillaria ostoyae–Pinus pinaster pathosystem as reference. We used the model to study the effects of rotation length on the evolution of virulence and the propagation of the fungus within a forest landscape composed of even-aged stands regularly altered by clear-cutting and thinning operations. The life cycle of the fungus modeled combines asexual and sexual reproduction modes, and also includes parasitic and saprotrophic phases. Moreover, the tree susceptibility to the pathogen is primarily determined by the age of the stand. Our simulations indicated that the shortest rotation length accelerated both the evolution of virulence and the development of the epidemics, whatever the genetic variability in the initial fungal population and the asexuality rate of the fungal species

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    Josefa Blaya

    Full Text Available 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.

  14. Antifungal Compound Isolated from Catharanthus roseus L. (Pink for Biological Control of Root Rot Rubber Diseases

    Directory of Open Access Journals (Sweden)

    R. Zahari

    2018-01-01

    Full Text Available Rigidoporus microporus, Ganoderma philippii, and Phellinus noxius are root rot rubber diseases and these fungi should be kept under control with environmentally safe compounds from the plant sources. Thus, an antifungal compound isolated from Catharanthus roseus was screened for its effectiveness in controlling the growth of these fungi. The antifungal compound isolated from C. roseus extract was determined through thin layer chromatography (TLC and nuclear magnetic resonance (NMR analysis. Each C. roseus of the DCM extracts was marked as CRD1, CRD2, CRD3, CRD4, CRD5, CRD6, and CRD7, respectively. TLC results showed that all of the C. roseus extracts peaked with red colour at Rf = 0.61 at 366 nm wavelength, except for CRD7. The CRD4 extract was found to be the most effective against R. microporus and G. philippii with inhibition zones of 3.5 and 1.9 mm, respectively, compared to that of other extracts. These extracts, however, were not effective against P. noxius. The CRD4 extract contained ursolic acid that was detected by NMR analysis and the compound could be developed as a biocontrol agent for controlling R. microporus and G. philippii. Moreover, little or no research has been done to study the effectiveness of C. roseus in controlling these fungi.

  15. Quantifying the Severity of Phytophthora Root Rot Disease in Avocado Trees Using Image Analysis

    Directory of Open Access Journals (Sweden)

    Arachchige Surantha Ashan Salgadoe

    2018-02-01

    Full Text Available Phytophthora root rot (PRR infects the roots of avocado trees, resulting in reduced uptake of water and nutrients, canopy decline, defoliation, and, eventually, tree mortality. Typically, the severity of PRR disease (proportion of canopy decline is assessed by visually comparing the canopy health of infected trees to a standardised set of photographs and a corresponding disease rating. Although this visual method provides some indication of the spatial variability of PRR disease across orchards, the accuracy and repeatability of the ranking is influenced by the experience of the assessor, the visibility of tree canopies, and the timing of the assessment. This study evaluates two image analysis methods that may serve as surrogates to the visual assessment of canopy decline in large avocado orchards. A smartphone camera was used to collect red, green, and blue (RGB colour images of individual trees with varying degrees of canopy decline, with the digital photographs then analysed to derive a canopy porosity percentage using a combination of ‘Canny edge detection’ and ‘Otsu’s’ methods. Coinciding with the on-ground measure of canopy porosity, the canopy reflectance characteristics of the sampled trees measured by high resolution Worldview-3 (WV-3 satellite imagery was also correlated against the observed disease severity rankings. Canopy porosity values (ranging from 20–70% derived from RGB images were found to be significantly different for most disease rankings (p < 0.05 and correlated well (R2 = 0.89 with the differentiation of three disease severity levels identified to be optimal. From the WV-3 imagery, a multivariate stepwise regression of 18 structural and pigment-based vegetation indices found the simplified ratio vegetation index (SRVI to be strongly correlated (R2 = 0.96 with the disease rankings of PRR disease severity, with the differentiation of four levels of severity found to be optimal.

  16. 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)

    Haq, M.I.; Tahir, M.I.; Mahmood, S.

    2012-01-01

    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)

  17. Abscisic Acid as a Dominant Signal in Tomato During Salt Stress Predisposition to Phytophthora Root and Crown Rot

    Directory of Open Access Journals (Sweden)

    Matthew F. Pye

    2018-04-01

    Full Text Available Salt stress predisposes plants to Phytophthora root and crown rot in an abscisic acid (ABA-dependent manner. We used the tomato–Phytophthora capsici interaction to examine zoospore chemoattraction and assessed expression of pathogenesis-related (PR genes regulated by salicylic acid (SA and jasmonic acid (JA following a salt-stress episode. Although salt treatment enhances chemoattraction of tomato roots to zoospores, exudates from salt-stressed roots of ABA-deficient mutants, which do not display the predisposition phenotype, have a similar chemoattraction as exudates from salt-stressed, wild-type roots. This suggests that ABA action during predisposing stress enhances disease through effects on plant responses occurring after initial contact and during ingress by the pathogen. The expression of NCED1 (ABA synthesis and TAS14 (ABA response in roots generally corresponded to previously reported changes in root ABA levels during salt stress onset and recovery in a pattern that was not altered by infection by P. capsici. The PR genes, P4 and PI-2, hallmarks in tomato for SA and JA action, respectively, were induced in non-stressed roots during infection and strongly suppressed in infected roots exposed to salt-stress prior to inoculation. However, there was a similar proportional increase in pathogen colonization observed in salt-stressed plants relative to non-stressed plants in both wild-type and a SA-deficient nahG line. Unlike the other tomato cultivars used in this study that showed a strong predisposition phenotype, the processing tomato cv. ‘Castlemart’ and its JA mutants were not predisposed by salt. Salt stress predisposition to crown and root rot caused by P. capsici appears to be strongly conditioned by ABA-driven mechanisms in tomato, with the stress compromising SA-and JA-mediated defense-related gene expression during P. capsici infection.

  18. Calonectria spp. causing leaf spot, crown and root rot of ornamental plants in Tunisia

    NARCIS (Netherlands)

    Lombard, L.; Polizzi, G.; Guarnaccia, V.; Vitale, A.; Crous, P.W.

    2011-01-01

    Calonectria spp. are important pathogens of ornamental plants in nurseries, especially in the Northern Hemisphere. They are commonly associated with a wide range of disease symptoms of roots, leaves and shoots. During a recent survey in Tunisia, a number of Calonectria spp. were isolated from

  19. Calonectria spp. causing leaf spot, crown and root rot of ornamental plants in Tunisia

    NARCIS (Netherlands)

    Lombard, L.; Polizzi, G.; Guarnaccia, V.; Vitale, A.; Crous, P.W.

    2012-01-01

    Calonectria spp. are important pathogens of ornamental plants in nurseries, especially in the Northern Hemisphere. They are commonly associated with a wide range of disease symptoms of roots, leaves and shoots. During a recent survey in Tunisia, a number of Calonectria spp. were isolated from

  20. Heterobasidion annosum root rot in Picea abies: Variability in aggressiveness and resistance

    Energy Technology Data Exchange (ETDEWEB)

    Swedjemark, G.

    1995-12-31

    In greenhouse experiments 3-4 year-old plants of Picea abies and Pinus sylvestris were inoculated with the root rot fungus Heterobasidion annosum. The growth rates of 25 S and 14 P isolates of the fungus were measured in the sapwood of about 25 rametes each of 98 Norway spruce clones and in 150 seedlings each of Norway spruce and Scots pine. Correlations were determined between fungal sapwood growth and a variety of variables, i.e. the physical stage, growth rhythm, size and condition of the cuttings, provenance and the growth capacity of the clones estimated in field tests. Genetic parameters such as phenotypic and genotypic variance, genotypic coefficient of variance and broad sense heritability were calculated. H. annosum infection incidence was close to 100 % for inoculated Norway spruce clones, and the mortality rate was about 1 %. Fungal growth in sapwood differed significantly among clones and among fungal isolates. The genotypic correlation coefficient was large (30 %) and broad sense heritability was 0.35. This suggests that good selection progress can be achieved in breeding programs. The physical stage (bud-flush, vegetative and post bud-set stage) of the clones contributed significantly to the total variation in fungal growth. The population structure of H. annosum was studied in two 25-year-old, first generation stands of Norway spruce. The stands had been thinned one and seven years earlier, respectively. All stumps and remaining trees were sampled for H. annosum isolates. The isolates were tested with somatic incompatibility to detect single genets and the distribution of genets in the stand was determined. About 70 % of the 7-year-old thinning stumps were colonized by H, annosum, and 50 % of these stumps were colonized by more than one fungal genet. Sixty-three percent of the remaining trees were infected with H. annosum but among them there was only one genet per tree. 104 refs, 12 figs

  1. Evaluation of Trichoderma Isolates for Biological Control of Rhizoctonia Root Rot of Bean in Zanjan

    Directory of Open Access Journals (Sweden)

    M. Khodae

    2016-03-01

    Full Text Available Introduction: Rhizoctonia solani is one of the major pathogens causing root rot in the main bean-growing regions in Zanjan province. Under favorable conditions, yield losses in commercial bean fields due to Rhizoctonia root rot have exceeded 50 percent reduction in pod and seed numbers per plants. In 2012 most isolates of the pathogen from severely infected bean fields in Zanjan were assessed to AG-4. R. solani AG-4 can attack other commercial crops such as potato, alfalfa, barley, tomato, cabbage, etc. which are grown in rotation with bean in the area. Thus, the disease is unlikely to be controlled by crop rotation. Moreover, there is no registered resistant bean cultivar against the disease in Iran. Although soil treatment with fungicides is the only effective control method in the region, according to environmental and side effects of fungicides, alternative approaches such as biocontrol method using Trichoderma species is considered. Materials and Methods: The study was conducted using five isolates of Trichoderma (T12-0, T12-N, T19, T6, T95 received from the Department of Plant Pathology, Ferdowsi University of Mashhad (Dr. H. Rouhani and six isolates of Trichoderma (T36,T125, T131, T93, T89, T25 collected in 2011 from rhizosphere of bean plants in the commercial bean fields of Zanjan province (Table 1. Trichoderma isolates were evaluated for their potential to antagonize in vitro the plant pathogenic fungus R. solani using three different tests. In the first test, each isolate of Trichoderma was grown in a dual culture with R. solani AG-4 strain Rh7 on PDA and incubated at 25˚C. Radii of colony of R. solani were measured after 72 h. In the second test the ability of Trichoderma isolates to produce volatile inhibitors was measured. This experiment was conducted in two conditions involving the same time culturing of Trichoderma and Rhizoctonia and isolating 72 h early growing Trichoderma. For both tests the percentage of inhibition was

  2. Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures.

    Science.gov (United States)

    Chinta, Yufita D; Kano, Kazuki; Widiastuti, Ani; Fukahori, Masaru; Kawasaki, Shizuka; Eguchi, Yumi; Misu, Hideyuki; Odani, Hiromitsu; Zhou, Songying; Narisawa, Kazuhiko; Fujiwara, Kazuki; Shinohara, Makoto; Sato, Tatsuo

    2014-08-01

    Recent reports indicate that organic fertilisers have a suppressive effect on the pathogens of plants grown under hydroponic systems. Furthermore, microorganisms exhibiting antagonistic activity to diseases have been observed in organic hydroponic systems. This study evaluated the effect of corn steep liquor (CSL) on controlling lettuce root rot disease [Fusarium oxysporum f.sp. lactucae (FOL)] in a hydroponic system. The effect of CSL and Otsuka A (a chemical fertiliser) on the inhibition of FOL in terms of mycelial growth inhibition was tested in vivo. Addition of CSL suppressed FOL infection rates. CSL inhibited FOL infection by 26.3-42.5% from 2 days after starting incubation. In comparison, Otsuka A inhibited FOL growth by 5.5-19.4%. In addition, four of 10 bacteria isolated from the nutrient media containing CSL exhibited inhibition zones preventing FOL mycelial growth. We found that CSL suppressed FOL in lettuce via its antifungal and biostimulatory effects. We suggest that activation of beneficial microorganisms present in CSL may be used to decrease lettuce root rot disease and contribute to lettuce root growth. © 2014 Society of Chemical Industry.

  3. 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.

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

    International Nuclear Information System (INIS)

    Nakamura, H.; Ikeda, K.; Arakawa, M.; Matsumoto, N.

    2002-01-01

    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

  5. Impacts of previous crops on Fusarium foot and root rot, and on yields of durum wheat in North West Tunisia

    Directory of Open Access Journals (Sweden)

    Samia CHEKALI

    2016-07-01

    Full Text Available The impacts of ten previous crop rotations (cereals, legumes and fallow on Fusarium foot and root rot of durum wheat were investigated for three cropping seasons in a trial established in 2004 in Northwest Tunisia. Fungi isolated from the roots and stem bases were identified using morphological and molecular methods, and were primarily Fusarium culmorum and F. pseudograminearum. Under low rainfall conditions, the previous crop affected F. pseudograminearum incidence on durum wheat roots but not F. culmorum. Compared to continuous cropping of durum wheat, barley as a previous crop increased disease incidence more than fivefold, while legumes and fallow tended to reduce incidence.  Barley as a previous crop increased wheat disease severity by 47%, compared to other rotations. Grain yield was negatively correlated with the incidence of F. culmorum infection, both in roots and stem bases, and fitted an exponential model (R2 = -0.61 for roots and -0.77 for stem bases, P<0.0001. Fusarium pseudograminearum was also negatively correlated with yield and fitted an exponential model (R2 = -0.53 on roots and -0.71 on stem bases, P < 0.0001 but was not correlated with severity.

  6. Isolation screening and characterisation of local beneficial rhizobacteria based upon their ability to suppress the growth of Fusarium oxysporum f. sp. radicis-lycopersici and tomato foot and root rot

    Science.gov (United States)

    Tomato crown and root rot or tomato foot and root rot (TFRR) is caused by the phytopathogenic fungus Fusarium oxysporum f. sp. radicis-lycopersici (Forl). The disease occurs in both greenhouse and outdoor tomato cultivations and cannot be treated efficiently with the existing fungicides. We conducte...

  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. Development and application of qPCR and RPA genus and species-specific detection of Phytophthora sojae and Phytophthora sansomeana root rot pathogens of soybean

    Science.gov (United States)

    Phytophthora root rot of soybean, caused by Phytophthora sojae is one of the most important diseases in the Midwest US, causing losses of up to 44 million bushels per year. Disease may also be caused by P. sansomeana, however the prevalence and damage caused by this species is not well known, partl...

  9. 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...

  10. 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 - others: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

  11. Relative Efficacy of On-Farm Weeds as Soil-Amendement for Managing Dry Root Rot of Clusterbean in an Arid Environment

    Directory of Open Access Journals (Sweden)

    R. Mawar

    2006-12-01

    Full Text Available The effectiveness of certain on-farm weeds as soil amendments was ascertained against Macrophomina phaseolina, a soil-borne pathogen causing dry root rot of crops grown under rainfed conditions in arid regions. Population changes in M. phaseolina were determined in soils amended separately with residues (1%, w:w of Aerva persica, Celosia argentea, Corchorus depressus, Euphorbia hirta, Heliotropium subulatum and Polycarpaea corymbosa, for a period of 90 days. Significant reductions by 90.4–100% in the population of M. phaseolina were achieved with all the weed residues except P. corymbosa. Celosia and Euphorbia residues completely eradicated viable propagules of M. phaseolina. A strong increase (44–61% in the population of antagonistic actinomycetes was also found in soil amended with Corchorus and Euphorbia. In field tests, soil amended (50 g m2 with Euphorbia, Aerva and Celosia residues significantly reduced dry root rot incidence on clusterbean and also reduced M. phaseolina propagules in the soil. However, dry root rot incidence in Polycarpaea-amended soil (5.8–24.6% was not significantly different from that in non-amended soil (4.3–25.3% in both years of the experiment. P. corymbosa also increased the number of propagules of M. phaseolina in the soil. The results demonstrate that dry root rot of rainfed-cultivated annual crops in arid land can be managed with certain weeds as a soil amendment.

  12. Concentration- and Time-Dependent Effects of Isothiocyanates Produced from Brassicaceae Shoot Tissues on the Pea Root Rot Pathogen Aphanomyces euteiches

    NARCIS (Netherlands)

    Hossain, S.; Bergkvist, G.; Berglund, K.; Glinwood, R.; Kabouw, P.; Martensson, A.; Persson, P.

    2014-01-01

    Isothiocyanates (ITCs) hydrolyzed from glucosinolates (GSLs) in Brassicaceae tissue are toxic to soil organisms. In this study, the effect of aliphatic and aromatic ITCs from hydrated dry Brassicaceae shoot tissues on the mycelium and oospores of the pea root rot pathogen Aphanomyces euteiches was

  13. Biocontrol of Fusarium Crown and Root Rot and Promotion of Growth of Tomato by Paenibacillus Strains Isolated from Soil

    Science.gov (United States)

    Xu, Sheng Jun

    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 the mycelial growth of Fusarium oxysporum f. sp. radicis-lycopersici in vitro. The seven Paenibacillus strains enhanced a range of growth parameters in tomato plants under greenhouse conditions, in comparison with non-inoculated control plants. Notably, treatment of tomato plants with one identified strain, P. polymyxa SC09-21, resulted in 80.0% suppression of fusarium crown and root rot under greenhouse conditions. The plant growth promoting and antifungal activity of P. polymyxa SC09-21 identified in this study highlight its potential suitability as a bioinoculant. PMID:25071385

  14. Endophytic Bacteria Improve Plant Growth, Symbiotic Performance of Chickpea (Cicer arietinum L. and Induce Suppression of Root Rot Caused by Fusarium solani under Salt Stress

    Directory of Open Access Journals (Sweden)

    Dilfuza Egamberdieva

    2017-09-01

    Full Text Available Salinity causes disturbance in symbiotic performance of plants, and increases susceptibility of plants to soil-borne pathogens. Endophytic bacteria are an essential determinant of cross-tolerance to biotic and abiotic stresses in plants. The aim of this study was to isolate non–rhizobial endophytic bacteria from the root nodules of chickpea (Cicer arietinum L., and to assess their ability to improve plant growth and symbiotic performance, and to control root rot in chickpea under saline soil conditions. A total of 40 bacterial isolates from internal root tissues of chickpea grown in salinated soil were isolated. Four bacterial isolates, namely Bacillus cereus NUU1, Achromobacter xylosoxidans NUU2, Bacillus thuringiensis NUU3, and Bacillus subtilis NUU4 colonizing root tissue demonstrated plant beneficial traits and/or antagonistic activity against F. solani and thus were characterized in more detail. The strain B. subtilis NUU4 proved significant plant growth promotion capabilities, improved symbiotic performance of host plant with rhizobia, and promoted yield under saline soil as compared to untreated control plants under field conditions. A combined inoculation of chickpea with M. ciceri IC53 and B. subtilis NUU4 decreased H2O2 concentrations and increased proline contents compared to the un-inoculated plants indicating an alleviation of adverse effects of salt stress. Furthermore, the bacterial isolate was capable to reduce the infection rate of root rot in chickpea caused by F. solani. This is the first report of F. solani causing root rot of chickpea in a salinated soil of Uzbekistan. Our findings demonstrated that the endophytic B. subtilis strain NUU4 provides high potentials as a stimulator for plant growth and as biological control agent of chickpea root rot under saline soil conditions. These multiple relationships could provide promising practical approaches to increase the productivity of legumes under salt stress.

  15. 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.

  16. 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)

    Bokhari, S.S.; Tariq, S.; Ali, S.A.

    2014-01-01

    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)

  17. 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 treated seeds with bioagents in first of November gave the

  18. Study the Reaction of Some Barley Cultivars to Rhizoctonia solani AG-8, the Causal Agent of Root Rot Disease

    Directory of Open Access Journals (Sweden)

    M. Yazdani Kohanstani

    2016-03-01

    Full Text Available Introduction: Barley is one of the important agricultural products, mostly as livestock feed, and secondly for its important role in human nutrition as bread, soups, baby food and etc. It has the second-largest rank of cultivation area and yield of the national grain production and the Isfahan province, with production 5% of total barley yield, has been ranked eighth in 2010. Because its consumption exceed over the production, barley is one of the major imports to the country. In addition to, agronomy operations, plant diseases are important factors in yield loss. Rhizoctonia root rot (caused by soil-inhabiting fungus Rhizoctonia solani is one of the important diseases of cereals include barley over the worldwide cultivation area. Apropriate soil fertility, delaying planting dates, crop rotation with insensitive crops such as legumes, planting resistant varieties and fungicide seed dressing are recommended methods to reduce disease damage. Chemical control of this disease is difficult because of its soil-born the pathogen. Therefore, reducing disease level requires application of other methods especially resistance cultivars. Materials and Methods In this research, the reaction of 8 barley cultivars were examined against root rot disease in greenhouse conditions, in the winter of 2009. Fifteen isolates of the fungus were isolated from infected barley fields in the Isfahan province and their pathogenicity was examined on barley. One isolate with the highest pathogenicity potential was selected and special tests showed that the isolate was Rhizoctonia solani AG-8. The experiment was conducted in a completely randomized design with 4 replications. The test plants were harvested at two times of 4 & 8 weeks after planting. Following parameters were measured: 1- dry weight of plant root and aerial part, 2- disease severity as an index of subcrown internodes infection. Results and discussion Statistical analysis of recorded data showed that there were

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

    Energy Technology Data Exchange (ETDEWEB)

    Borrego-Benjumea, A.I.; Melero-Vara, J.M.; Basallote-Ureba, M.J.

    2015-07-01

    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 incubat. (Author)

  20. 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.

  1. Comparative Methods of Application of Wild Plant Parts on Growth and in the Control of Root Rot Fungi of Leguminous Crops

    International Nuclear Information System (INIS)

    Ikram, N.; Dawae, S.

    2016-01-01

    Present research work was carried out for the management of root rot fungi with wild plant part capsules and pellets formulation in soil. When application of pellets and capsules was carried out with Prosopis juliflora stem, leaves and flowers showed significant reduction in disease incidence and enhancement in growth and physiological parameters. Colonization of Fusarium spp., Macrophomina phaseolina and Rhizoctonia solani was completely suppressed when P. juliflora leaves pellets incorporated in soil. Physiological parameters such as chlorophyll a and b and protein were significantly increased when leaves pellets incorporated in soil at the rate of 1 percent w/w so P. juliflora leaves pellets were most effective in the control of root rot fungi and enhanced the growth of crop plants. (author)

  2. Management of chili pepper root rot and wilt (caused by Phytophthora nicotianae) by grafting onto resistant rootstock

    OpenAIRE

    Mourad SAADOUN; Mohamed Bechir ALLAGUI

    2013-01-01

    Root rot and plant wilting caused by Phytophthora nicotianae is a severe disease of chili pepper (Capsicum annuum L.) in open fields and under greenhouse production in Tunisia. Chili pepper grafting for disease manage- ment is attracting increased interest in recent years. Using the tube grafting technique, different compatible scion/rootstock combinations were obtained with the wild-type pepper SCM334 and the local chili pepper cultivars ‘Beldi’ and ‘Baker’. SCM334 was resistant to P. nicoti...

  3. Construction of 2 intraspecific linkage maps and identification of resistance QTLs for Phytophthora capsici root-rot and foliar-blight diseases of pepper (Capsicum annuum L.).

    Science.gov (United States)

    Ogundiwin, Ebenezer A; Berke, Terry F; Massoudi, Mark; Black, Lowell L; Huestis, Gordon; Choi, Doil; Lee, Sanghyeob; Prince, James P

    2005-08-01

    Two linkage maps of pepper were constructed and used to identify quantitative trait loci (QTLs) conferring resistance to Phytophthora capsici. Inoculations were done with 7 isolates: 3 from Taiwan, 3 from California, and 1 from New Mexico. The first map was constructed from a set of recombinant inbred lines (RILs) of the PSP-11 (susceptible) x PI201234 (resistant) cross; and the second map was from a set of F(2) lines of the Joe E. Parker' (susceptible) x 'Criollo de Morelos 334' (resistant) cross. The RIL map covered 1466.1 cM of the pepper genome, and it consisted of 144 markers -- 91 amplified fragment length polymorphisms (AFLPs), 34 random amplified polymorphic DNA (RAPDs), 15 simple sequence repeats (SSRs), 1 sequence characterized amplified region (SCAR), and 3 morphological markers -- distributed over 17 linkage groups. The morphological markers mapped on this population were erect fruit habit (up), elongated fruit shape (fs(e)), and fasciculate fruit clusters (fa). The F(2) map consisted of 113 markers (51 AFLPs, 45 RAPDs, 14 SSRs, and 3 SCARs) distributed in 16 linkage groups, covering a total of 1089.2 cM of the pepper genome. Resistance to both root rot and foliar blight were evaluated in the RIL population using the 3 Taiwan isolates; the remaining isolates were used for the root-rot test only. Sixteen chromosomal regions of the RIL map contained single QTLs or clusters of resistance QTLs that had an effect on root rot and (or) foliar blight, revealing a complex set of genetics involved in resistance to P. capsici. Five QTLs were detected in the F(2) map that had an effect on resistance to root rot.

  4. Differential responses of vanilla accessions to root rot and colonization by Fusarium oxysporum f. sp. radicis-vanillae.

    Directory of Open Access Journals (Sweden)

    Sayuj eKoyyappurath

    2015-12-01

    Full Text Available 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

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

    Science.gov (United States)

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

  6. Monitoring cotton root rot by synthetic Sentinel-2 NDVI time series using improved spatial and temporal data fusion.

    Science.gov (United States)

    Wu, Mingquan; Yang, Chenghai; Song, Xiaoyu; Hoffmann, Wesley Clint; Huang, Wenjiang; Niu, Zheng; Wang, Changyao; Li, Wang; Yu, Bo

    2018-01-31

    To better understand the progression of cotton root rot within the season, time series monitoring is required. In this study, an improved spatial and temporal data fusion approach (ISTDFA) was employed to combine 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Different Vegetation Index (NDVI) and 10-m Sentinetl-2 NDVI data to generate a synthetic Sentinel-2 NDVI time series for monitoring this disease. Then, the phenology of healthy cotton and infected cotton was modeled using a logistic model. Finally, several phenology parameters, including the onset day of greenness minimum (OGM), growing season length (GLS), onset of greenness increase (OGI), max NDVI value, and integral area of the phenology curve, were calculated. The results showed that ISTDFA could be used to combine time series MODIS and Sentinel-2 NDVI data with a correlation coefficient of 0.893. The logistic model could describe the phenology curves with R-squared values from 0.791 to 0.969. Moreover, the phenology curve of infected cotton showed a significant difference from that of healthy cotton. The max NDVI value, OGM, GSL and the integral area of the phenology curve for infected cotton were reduced by 0.045, 30 days, 22 days, and 18.54%, respectively, compared with those for healthy cotton.

  7. Transcriptome responses of an ungrafted Phytophthora root rot tolerant avocado (Persea americana) rootstock to flooding and Phytophthora cinnamomi.

    Science.gov (United States)

    Reeksting, B J; Olivier, N A; van den Berg, N

    2016-09-22

    Avocado (Persea americana Mill.) is a commercially important fruit crop worldwide. A major limitation to production is the oomycete Phytophthora cinnamomi, which causes root rot leading to branch-dieback and tree death. The decline of orchards infected with P. cinnamomi occurs much faster when exposed to flooding, even if flooding is only transient. Flooding is a multifactorial stress compromised of several individual stresses, making breeding and selection for tolerant varieties challenging. With more plantations occurring in marginal areas, with imperfect irrigation and drainage, understanding the response of avocado to these stresses will be important for the industry. Maintenance of energy production was found to be central in the response to flooding, as seen by up-regulation of transcripts related to glycolysis and induction of transcripts related to ethanolic fermentation. Energy-intensive processes were generally down-regulated, as evidenced by repression of transcripts related to processes such as secondary cell-wall biosynthesis as well as defence-related transcripts. Aquaporins were found to be down-regulated in avocado roots exposed to flooding, indicating reduced water-uptake under these conditions. The transcriptomic response of avocado to flooding and P. cinnamomi was investigated utilizing microarray analysis. Differences in the transcriptome caused by the presence of the pathogen were minor compared to transcriptomic perturbations caused by flooding. The transcriptomic response of avocado to flooding reveals a response to flooding that is conserved in several species. This data could provide key information that could be used to improve selection of stress tolerant rootstocks in the avocado industry.

  8. 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)

    Rafi, H.; Dawar, S.; Zaki, M.J.

    2015-01-01

    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)

  9. Molecular variability among isolates of Fusarium oxysporum associated with root rot disease of Agave tequilana.

    Science.gov (United States)

    Vega-Ramos, Karla L; Uvalle-Bueno, J Xavier; Gómez-Leyva, Juan F

    2013-04-01

    In this study, 115 isolates of Fusarium oxysporum from roots of Agave tequilana Weber cv azul plants and soil in commercial plantations in western Mexico were characterized using morphological and molecular methods. Genetic analyses of monosporic isolates included restriction enzyme analysis of rDNA (ARDRA) using HaeIII and HinfI, and genetic diversity was determined using Box-PCR molecular markers. Box-PCR analysis generated 14 groups. The groups correlated highly with the geographic location of the isolate and sample type. These results demonstrate the usefulness of ARDRA and Box-PCR techniques in the molecular characterization of the Fusarium genus for the discrimination of pathogenic isolates.

  10. Phytophthora cinnamon causing stem canker and root rot of nursery-grown Platanus × acerifolia: first report in the Northern emisphere

    Directory of Open Access Journals (Sweden)

    Massimo PILOTTI

    2014-05-01

    Full Text Available Lethal stem and root cankers were observed in nursery-grown Platanus × acerifolia trees in Rome. Externally, canker lesions appeared as bluish or blackish areas starting from the stem base and extending upward. Inner bark was necrotised. In some cases an irregularly-shaped callus reaction attempted to heal the bark lesions. Black-stained necrosis affected the primary roots and the small branch roots to different degrees. The presence of Ceratocystis platani was excluded in the diseased trees. Phytophthora-like organisms were isolated from the altered tissue. Morphological and ITS-region-based analyses identified the isolates as Phytophthora cinnamomi. A pathogenicity test confirmed P. cinnamomi as the causal agent of the disease here defined as: stem canker and root rot of plane tree. This is the first report of P. cinnamomi in Platanus spp. in the Northern emisphere.

  11. Race Characterization of Phytophthora root rot on Capsicum in Taiwan as a Basis for Anticipatory Resistance Breeding.

    Science.gov (United States)

    Barchenger, Derek W; Sheu, Zong-Ming; Kumar, Sanjeet; Lin, Shih-Wen; Burlakoti, Rishi R; Bosland, Paul W

    2018-02-27

    Peppers (Capsicum sp.) are an increasingly important crop because of their use as a vegetable, spice, and food colorant. The oomycete Phytophthora capsici is one of the most devastating pathogens to pepper production worldwide, causing more than $100 million in losses annually. Developing cultivars resistant to P. capsici is challenging because of the many physiological races that exist and new races that are continuously evolving. This problem is confounded by the lack of a universal system of race characterization. As a basis to develop a global anticipatory breeding program, New Mexico Recombinant Inbred Lines (NMRILs) functioned as a host differential for Phytophthora root rot to characterize the race structure of P. capsici populations in Taiwan. Using the NMRILs, 24 new races were identified, illustrating the utility and usefulness of the NMRILs for anticipatory breeding. Virulence of P. capsici was observed to be geographically specific and in two virulence clusters. Interestingly, all but two isolates collected in 2016 were the A2 mating type, which is a shift from the predominantly A1 mating type isolates collected prior to 2008. The NMRILs host differential provides an approach for scientists to work together on a global scale when breeding for resistance as well as on a local level for regional gene deployment. Additionally, we propose that the current race numbering system, which has no biological meaning, be supplemented with the virulence phenotype, based on the susceptible NMRILs to a given isolate. This work provides insights into the population dynamics of P. capsici and interactions within the highly complex Capsicum-Phytophthora pathosystem, and offers a basis for similar research in other crops.

  12. 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.

  13. The role of defoliation and root rot pathogen infection in driving the mode of drought-related physiological decline in Scots pine (Pinus sylvestris L.).

    Science.gov (United States)

    Aguadé, D; Poyatos, R; Gómez, M; Oliva, J; Martínez-Vilalta, J

    2015-03-01

    Drought-related tree die-off episodes have been observed in all vegetated continents. Despite much research effort, however, the multiple interactions between carbon starvation, hydraulic failure and biotic agents in driving tree mortality under field conditions are still not well understood. We analysed the seasonal variability of non-structural carbohydrates (NSCs) in four organs (leaves, branches, trunk and roots), the vulnerability to embolism in roots and branches, native embolism (percentage loss of hydraulic conductivity (PLC)) in branches and the presence of root rot pathogens in defoliated and non-defoliated individuals in a declining Scots pine (Pinus sylvestris L.) population in the NE Iberian Peninsula in 2012, which included a particularly dry and warm summer. No differences were observed between defoliated and non-defoliated pines in hydraulic parameters, except for a higher vulnerability to embolism at pressures below -2 MPa in roots of defoliated pines. No differences were found between defoliation classes in branch PLC. Total NSC (TNSC, soluble sugars plus starch) values decreased during drought, particularly in leaves. Defoliation reduced TNSC levels across tree organs, especially just before (June) and during (August) drought. Root rot infection by the fungal pathogen Onnia P. Karst spp. was detected but it did not appear to be associated to tree defoliation. However, Onnia infection was associated with reduced leaf-specific hydraulic conductivity and sapwood depth, and thus contributed to hydraulic impairment, especially in defoliated pines. Infection was also associated with virtually depleted root starch reserves during and after drought in defoliated pines. Moreover, defoliated and infected trees tended to show lower basal area increment. Overall, our results show the intertwined nature of physiological mechanisms leading to drought-induced mortality and the inherent difficulty of isolating their contribution under field conditions. © The

  14. Evaluation of the biocontrol efficacy of a Serratia marcescens strain indigenous to tea rhizosphere for the management of root rot disease in tea.

    Directory of Open Access Journals (Sweden)

    Gargee Dhar Purkayastha

    Full Text Available The aim of the present study is to evaluate plant growth promoting and biocontrol efficacy of a Serratia marcescens strain ETR17 isolated from tea rhizosphere for the effective management of root rot disease in tea. Isolated bacterial culture ETR17 showed significant level of in vitro antagonism against nine different foliar and root pathogens of tea. The phenotypic and molecular characterization of ETR17 revealed the identity of the bacterium as Serratia marcescens. The bacterium was found to produce several hydrolytic enzymes like chitinase, protease, lipase, cellulase and plant growth promoting metabolites like IAA and siderophore. Scanning electron microscopic studies on the interaction zone between pathogen and antagonistic bacterial isolate revealed severe deformities in the fungal mycelia. Spectral analyses (LC-ESI-MS, UV-VIS spectrophotometry and HPLC and TLC indicated the presence of the antibiotics pyrrolnitrin and prodigiosin in the extracellular bacterial culture extracts. Biofilm formation by ETR17 on polystyrene surface was also observed. In vivo application of talc-based formulations prepared with the isolate ETR17 in tea plantlets under green house conditions revealed effective reduction of root-rot disease as well as plant growth promotion to a considerable extent. Viability studies with the ETR17 talc formulation showed the survivability of the isolate up to six months at room temperature. The sustenance of ETR17 (concentration of 8-9x108 cfu g-1 in the soil after the application of talc formulation was recorded by ELISA. Safety studies revealed that ETR17 did not produce hemolysin as observed in pathogenic Serratia strains. The biocontrol strain reported in this study can be used for field application in order to minimize the use of chemical fungicides for disease control in tea gardens.

  15. Evaluation of the biocontrol efficacy of a Serratia marcescens strain indigenous to tea rhizosphere for the management of root rot disease in tea.

    Science.gov (United States)

    Dhar Purkayastha, Gargee; Mangar, Preeti; Saha, Aniruddha; Saha, Dipanwita

    2018-01-01

    The aim of the present study is to evaluate plant growth promoting and biocontrol efficacy of a Serratia marcescens strain ETR17 isolated from tea rhizosphere for the effective management of root rot disease in tea. Isolated bacterial culture ETR17 showed significant level of in vitro antagonism against nine different foliar and root pathogens of tea. The phenotypic and molecular characterization of ETR17 revealed the identity of the bacterium as Serratia marcescens. The bacterium was found to produce several hydrolytic enzymes like chitinase, protease, lipase, cellulase and plant growth promoting metabolites like IAA and siderophore. Scanning electron microscopic studies on the interaction zone between pathogen and antagonistic bacterial isolate revealed severe deformities in the fungal mycelia. Spectral analyses (LC-ESI-MS, UV-VIS spectrophotometry and HPLC) and TLC indicated the presence of the antibiotics pyrrolnitrin and prodigiosin in the extracellular bacterial culture extracts. Biofilm formation by ETR17 on polystyrene surface was also observed. In vivo application of talc-based formulations prepared with the isolate ETR17 in tea plantlets under green house conditions revealed effective reduction of root-rot disease as well as plant growth promotion to a considerable extent. Viability studies with the ETR17 talc formulation showed the survivability of the isolate up to six months at room temperature. The sustenance of ETR17 (concentration of 8-9x108 cfu g-1) in the soil after the application of talc formulation was recorded by ELISA. Safety studies revealed that ETR17 did not produce hemolysin as observed in pathogenic Serratia strains. The biocontrol strain reported in this study can be used for field application in order to minimize the use of chemical fungicides for disease control in tea gardens.

  16. Burkholderia ginsengiterrae sp. nov. and Burkholderia panaciterrae sp. nov., antagonistic bacteria against root rot pathogen Cylindrocarpon destructans, isolated from ginseng soil.

    Science.gov (United States)

    Farh, Mohamed El-Agamy; Kim, Yeon-Ju; Van An, Hoang; Sukweenadhi, Johan; Singh, Priyanka; Huq, Md Amdadul; Yang, Deok-Chun

    2015-04-01

    Strain DCY85(T) and DCY85-1(T), isolated from rhizosphere of ginseng, were rod-shaped, Gram-reaction-negative, strictly aerobic, catalase positive and oxidase negative. 16S rRNA gene sequence analysis revealed that strain DCY85(T) as well as DCY85-1(T) belonged to the genus Burkholderia and were closely related to Burkholderia fungorum KACC 12023(T) (98.1 and 98.0 % similarity, respectively). The major polar lipids of strain DCY85(T) and DCY85-1(T) were phosphatidylethanolamine, one unidentified aminolipid and two unidentified phospholipids. The major fatty acids of both strains are C16:0, C18:1 ω7c and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c). The predominant isoprenoid quinone of each strain DCY85(T) and DCY85-1(T) was ubiquinone (Q-8) and the G+C content of their genomic DNA was 66.0 and 59.4 mol%, respectively, which fulfill the characteristic range of the genus Burkholderia. The polyamine content of both DCY85(T) and DCY85-1(T) was putrescine. Although both DCY85(T) and DCY85-1(T) have highly similar 16S rRNA and identical RecA and gyrB sequences, they show differences in phenotypic and chemotaxonomic characteristics. DNA-DNA hybridization results proved the consideration of both strains as two different species. Based on the results from our polyphasic characterization, strain DCY85(T) and DCY85-1(T) are considered novel Burkholderia species for which the name Burkholderia ginsengiterrae sp. nov and Burkholderia panaciterrae sp. nov are, respectively, proposed. An emended description of those strains is also proposed. DCY85(T) and DCY85-1(T) showed antagonistic activity against the common root rot pathogen of ginseng, Cylindrocarpon destructans. The proposed type strains are DCY85(T) (KCTC 42054(T) = JCM 19888(T)) and DCY85-1(T) (KCTC 42055(T) = JCM 19889(T)).

  17. Draft genome sequence of Bacillus velezensis 2A-2B strain: a rhizospheric inhabitant of Sporobolus airoides (Torr.) Torr., with antifungal activity against root rot causing phytopathogens.

    Science.gov (United States)

    Martínez-Raudales, Inés; De La Cruz-Rodríguez, Yumiko; Alvarado-Gutiérrez, Alejandro; Vega-Arreguín, Julio; Fraire-Mayorga, Ahuitz; Alvarado-Rodríguez, Miguel; Balderas-Hernández, Victor; Fraire-Velázquez, Saúl

    2017-01-01

    A Bacillus velezensis strain from the rhizosphere of Sporobolus airoides (Torr.) Torr . , a grass in central-north México, was isolated during a biocontrol of phytopathogens scrutiny study. The 2A-2B strain exhibited at least 60% of growth inhibition of virulent isolates of phytopathogens causing root rot. These phytopathogens include Phytophthora capsici , Fusarium solani , Fusarium oxysporum and Rhizoctonia solani . Furthermore, the 2A-2B strain is an indolacetic acid producer, and a plant inducer of PR1, which is an induced systemic resistance related gene in chili pepper plantlets. Whole genome sequencing was performed to generate a draft genome assembly of 3.953 MB with 46.36% of GC content, and a N50 of 294,737. The genome contains 3713 protein coding genes and 89 RNA genes. Moreover, comparative genome analysis revealed that the 2A-2B strain had the greatest identity (98.4%) with Bacillus velezensis.

  18. Managing Phytophthora crown and root rot on tomato by pre-plant treatments with biocontrol agents, resistance inducers, organic and mineral fertilizers under nursery conditions

    Directory of Open Access Journals (Sweden)

    Giovanna GILARDI

    2014-09-01

    Full Text Available Five trials were carried out under greenhouse conditions to test the efficacy of spray programmes based on biocontrol agents, phosphite-based fertilizers and a chemical inducer of resistance (acibenzolar-S-methyl, phosethyl-Al to control crown and root rot of tomato incited by Phytophthora nicotianae. The best disease control, under high disease pressure resulting from artificial inoculation, was obtained with three pre-plant leaf sprays at 7 d intervals with acibenzolar-S-methyl and with two mineral phosphite-based fertilizers. The disease reduction achieved was similar to that obtained with a single application of azoxystrobin and metalaxyl-M. Phosetyl-Al and the biocontrol agents Glomus spp. + Bacillus megaterium + Trichoderma, B. subtilis QST713, B. velezensis IT45 and the mixture T. asperellum ICC012 + T. gamsii ICC080 provided a partial disease control. Brassica carinata pellets did not control the disease.

  19. Controlling the root and stem rot of cucumber, caused by Pythium aphanidermatum, using resistance cultivars and grafting onto the cucurbit rootstocks

    Directory of Open Access Journals (Sweden)

    Fatemeh Rostami

    2015-02-01

    Full Text Available Cucumber damping off caused by Pythium aphanidermatum is the most important root and stem rot that limits greenhouse cultivations. In this study, relative susceptibility of grafting commercial cucumber cultivars including Alpha, Caspian 340, Storm 5910, Shalim 616, Delta scar, Janette 810, Festibal C5, Royal, Negyn, Soltan and Fadia on two Cucurbita rootstocks were evaluated against P. aphanidermatum . Disease severity, survival and seedling growth were used for the evaluation. The results showed significant differences between the studied cultivars (p≤0.01. Caspian 340 and Alpha with 15.7% and 100% disease severity had more and less tolerant to P. aphanidermatum, respectively. Cucurbita maxima rootstock was more resistant than Cucurbita pepo to P. aphanidermatum. C. pepo had less compatibility with the cucumber and showed little resistance to the pathogen. The study revealed that grafting Caspian340 on the resistant cucurbit rootstock i.e. Cucurbita maxima could be used as disease control strategies in greenhouses.

  20. 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)

    Otsyula, R.M.; Nderitu, J.H.

    1999-01-01

    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

  1. Applications of volatile compounds acquired from Muscodor heveae against white root rot disease in rubber trees (Hevea brasiliensis Müll. Arg.) and relevant allelopathy effects.

    Science.gov (United States)

    Siri-Udom, Sakuntala; Suwannarach, Nakarin; Lumyong, Saisamorn

    The bioactive compounds of the volatile metabolite-producing endophytic fungus, Muscodor heveae, were examined by the process of biofumigation for the purposes of controlling white root rot disease in rubber trees (Hevea brasiliensis Müll. Arg.). Volatile organic compounds (VOCs) of M. heveae possess antimicrobial activity against Rigidoporus microporus in vitro with 100 % growth inhibition. The synthetic volatile compounds test confirmed that the major component, 3-methylbutan-1-ol, and the minor compounds, 3-methylbutyl acetate and 2-methylpropanoic acid, inhibited root and shoot growth in the tested plants 3-methylbutan-1-ol showed ED 50 value and MIQ value on seed germination of ruzi grass, Arabidopsis thaliana Col-0 and tomato at 10, 5 and 5 μL -1 airspace, respectively. In vivo tests were carried out under greenhouse conditions using M. heveae inoculum fumigated soil that had been inoculated with R. microporus inoculum. After which, all seven treatments were compared. Significant differences were observed with a disease score at 150 d after treatment. Biofumigation by M. heveae showed great suppression of the disease. Biocontrol treatments; RMH40 (40 g kg -1 M. heveae inoculum) and RMH80 (80 g kg -1 M. heveae inoculum) were not found to be significantly different when compared with fungicide treatment (RT) and the non-infected control, but results were found to be significantly different from R. microporus infested (R) treatment. RMH40 and RMH80 revealed a low disease scores with a high survival rate of rubber tree seedling at 100 %, while R treatment showed the highest disease score of 4.8 ± 0.5 with a survival rate of rubber tree seedling at 25 %. The infected roots, appearing as a white colour. We have concluded that the bioactive VOCs of M. heveae would be an alternative method for the control of white root rot disease in rubber trees. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  2. Root Exudation in Common Ragweed (Ambrosia Artemisiifolia L.)

    Czech Academy of Sciences Publication Activity Database

    Figala, J.; Hohnová, Barbora; Moravcová, Dana; Lvončík, S.; Lojková, L.; Formánek, P.

    2016-01-01

    Roč. 5, č. 5 (2016), s. 1034-1037 ISSN 2278-1862 Institutional support: RVO:68081715 Keywords : ambrosia artemisiifolia * root exudates * amino acids * aliphatic organic acids * allelopathy Subject RIV: CB - Analytical Chemistry, Separation

  3. 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)

    Wagichunge, A.G.R; Owino, P.O; Waudo, S.W; Seif, A.A

    1999-01-01

    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

  4. 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.

  5. Measuring of -1,3 Glucanase Activity in Trichoderma Virens Isolates and Selection of the Best Isolates for Biological Control of Cucumber Root Rot

    Directory of Open Access Journals (Sweden)

    Fatemeh Zavvari

    2013-02-01

    Full Text Available In this study four isolates of  Trichoderma virens (T.virens 414, T.virens 414.8, T.virens 304 and  T.virens 404.4 were compared based on extra cellular β-1,3 glucanase production and biological control of root rot cucumber (Phytophthora drerchsleri in laboratory and green house experiments.The in vitro potential of those isolates were evaluated against  P.drechsleri  through production of volatile and dual culture. The pH (3, 5, 7, 8, 9 and temperature effects(5, 15, 20, 25, 30, 40˚C on Trichoderma mycelial growth were also evaluated. Colony growth rate of thease isolates were also studied in water agar culture medium containing carboxy methyle cellulose (CMC and showed direct correlation with β-1,3 glucanase secretion. According to results T. virens 304 and T. virens 414.8  were the best isolates in biocontrol of . drechsleri. Result also showed direct correlation between β-1,3 glucanase secretion and inhibition growth of phytophthora  mycelium and reduction of phytophthora infection.

  6. A novel, multiplexed, probe-based quantitative PCR assay for the soybean root- and stem-rot pathogen, Phytophthora sojae, utilizes its transposable element.

    Science.gov (United States)

    Haudenshield, James S; Song, Jeong Y; Hartman, Glen L

    2017-01-01

    Phytophthora root rot of soybean [Glycine max (L.) Merr.] is caused by the oomycete Phytophthora sojae (Kaufm. & Gerd.). P. sojae has a narrow host range, consisting primarily of soybean, and it is a serious pathogen worldwide. It exists in root and stem tissues as mycelium, wherein it can form oospores which subsequently germinate to release motile, infectious zoospores. Molecular assays detecting DNA of P. sojae are useful in disease diagnostics, and for determining the presence of the organism in host tissues, soils, and runoff or ponded water from potentially infested fields. Such assays as published have utilized ITS sequences from the nuclear ribosomal RNA genes in conventional PCR or dye-binding quantitative PCR (Q-PCR) but are not amenable to multiplexing, and some of these assays did not utilize control strategies for type I or type II errors. In this study, we describe primers and a bifunctional probe with specificity to a gypsy-like retroelement in the P. sojae genome to create a fluorogenic 5'-exonuclease linear hydrolysis assay, with a multiplexed internal control reaction detecting an exogenous target to validate negative calls, and with uracil-deglycosylase-mediated protection against carryover contamination. The assay specifically detected 13 different P. sojae isolates, and excluded 17 other Phytophthora species along with 20 non-Phytophthora fungal and oomycete species pathogenic on soybean. A diagnostic limit of detection of 34 fg total P. sojae DNA was observed in serial dilutions, equivalent to 0.3 genome, and a practical detection sensitivity of four zoospores per sample was achieved, despite losses during DNA extraction.

  7. 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.

  8. 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

  9. Characterization of Fusarium isolates from asparagus fields in southwestern Ontario and influence of soil organic amendments on Fusarium crown and root rot.

    Science.gov (United States)

    Borrego-Benjumea, Ana; Basallote-Ureba, María J; Melero-Vara, José M; Abbasi, Pervaiz A

    2014-04-01

    Fusarium crown and root rot (FCRR) of asparagus has a complex etiology with several soilborne Fusarium spp. as causal agents. Ninety-three Fusarium isolates, obtained from plant and soil samples collected from commercial asparagus fields in southwestern Ontario with a history of FCRR, were identified as Fusarium oxysporum (65.5%), F. proliferatum (18.3%), F. solani (6.4%), F. acuminatum (6.4%), and F. redolens (3.2%) based on morphological or cultural characteristics and polymerase chain reaction (PCR) analysis with species-specific primers. The intersimple-sequence repeat PCR analysis of the field isolates revealed considerable variability among the isolates belonging to different Fusarium spp. In the in vitro pathogenicity screening tests, 50% of the field isolates were pathogenic to asparagus, and 22% of the isolates caused the most severe symptoms on asparagus. The management of FCRR with soil organic amendments of pelleted poultry manure (PPM), olive residue compost, and fish emulsion was evaluated in a greenhouse using three asparagus cultivars of different susceptibility in soils infested with two of the pathogenic isolates (F. oxysporum Fo-1.5 and F. solani Fs-1.12). Lower FCRR symptom severity and higher plant weights were observed for most treatments on 'Jersey Giant' and 'Grande' but not on 'Mary Washington'. On all three cultivars, 1% PPM consistently reduced FCRR severity by 42 to 96% and increased plant weights by 77 to 152% compared with the Fusarium control treatment. Populations of Fusarium and total bacteria were enumerated after 1, 3, 7, and 14 days of soil amendment. In amended soils, the population of Fusarium spp. gradually decreased while the population of total culturable bacteria increased. These results indicate that soil organic amendments, especially PPM, can decrease disease severity and promote plant growth, possibly by decreasing pathogen population and enhancing bacterial activity in the soil.

  10. Mapping of a Novel Race Specific Resistance Gene to Phytophthora Root Rot of Pepper (Capsicum annuum) Using Bulked Segregant Analysis Combined with Specific Length Amplified Fragment Sequencing Strategy.

    Science.gov (United States)

    Xu, Xiaomei; Chao, Juan; Cheng, Xueli; Wang, Rui; Sun, Baojuan; Wang, Hengming; Luo, Shaobo; Xu, Xiaowan; Wu, Tingquan; Li, Ying

    2016-01-01

    Phytophthora root rot caused by Phytophthora capsici (P. capsici) is a serious limitation to pepper production in Southern China, with high temperature and humidity. Mapping PRR resistance genes can provide linked DNA markers for breeding PRR resistant varieties by molecular marker-assisted selection (MAS). Two BC1 populations and an F2 population derived from a cross between P. capsici-resistant accession, Criollo de Morelos 334 (CM334) and P. capsici-susceptible accession, New Mexico Capsicum Accession 10399 (NMCA10399) were used to investigate the genetic characteristics of PRR resistance. PRR resistance to isolate Byl4 (race 3) was controlled by a single dominant gene, PhR10, that was mapped to an interval of 16.39Mb at the end of the long arm of chromosome 10. Integration of bulked segregant analysis (BSA) and Specific Length Amplified Fragment sequencing (SLAF-seq) provided an efficient genetic mapping strategy. Ten polymorphic Simple Sequence Repeat (SSR) markers were found within this region and used to screen the genotypes of 636 BC1 plants, delimiting PhR10 to a 2.57 Mb interval between markers P52-11-21 (1.5 cM away) and P52-11-41 (1.1 cM). A total of 163 genes were annotated within this region and 31 were predicted to be associated with disease resistance. PhR10 is a novel race specific gene for PRR, and this paper describes linked SSR markers suitable for marker-assisted selection of PRR resistant varieties, also laying a foundation for cloning the resistance gene.

  11. Mapping of a Novel Race Specific Resistance Gene to Phytophthora Root Rot of Pepper (Capsicum annuum Using Bulked Segregant Analysis Combined with Specific Length Amplified Fragment Sequencing Strategy.

    Directory of Open Access Journals (Sweden)

    Xiaomei Xu

    Full Text Available Phytophthora root rot caused by Phytophthora capsici (P. capsici is a serious limitation to pepper production in Southern China, with high temperature and humidity. Mapping PRR resistance genes can provide linked DNA markers for breeding PRR resistant varieties by molecular marker-assisted selection (MAS. Two BC1 populations and an F2 population derived from a cross between P. capsici-resistant accession, Criollo de Morelos 334 (CM334 and P. capsici-susceptible accession, New Mexico Capsicum Accession 10399 (NMCA10399 were used to investigate the genetic characteristics of PRR resistance. PRR resistance to isolate Byl4 (race 3 was controlled by a single dominant gene, PhR10, that was mapped to an interval of 16.39Mb at the end of the long arm of chromosome 10. Integration of bulked segregant analysis (BSA and Specific Length Amplified Fragment sequencing (SLAF-seq provided an efficient genetic mapping strategy. Ten polymorphic Simple Sequence Repeat (SSR markers were found within this region and used to screen the genotypes of 636 BC1 plants, delimiting PhR10 to a 2.57 Mb interval between markers P52-11-21 (1.5 cM away and P52-11-41 (1.1 cM. A total of 163 genes were annotated within this region and 31 were predicted to be associated with disease resistance. PhR10 is a novel race specific gene for PRR, and this paper describes linked SSR markers suitable for marker-assisted selection of PRR resistant varieties, also laying a foundation for cloning the resistance gene.

  12. 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)

    Ikram, N.; Dawar, S.

    2015-01-01

    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)

  13. Detection and characterization of broad-spectrum antipathogen activity of novel rhizobacterial isolates and suppression of Fusarium crown and root rot disease of tomato.

    Science.gov (United States)

    Zhang, L; Khabbaz, S E; Wang, A; Li, H; Abbasi, P A

    2015-03-01

    To detect and characterize broad-spectrum antipathogen activity of indigenous bacterial isolates obtained from potato soil and soya bean leaves for their potential to be developed as biofungicides to control soilborne diseases such as Fusarium crown and root rot of tomato (FCRR) caused by Fusarium oxysporum f. sp. radicis-lycopersici (Forl). Thirteen bacterial isolates (Bacillus amyloliquefaciens (four isolates), Paenibacillus polymyxa (three isolates), Pseudomonas chlororaphis (two isolates), Pseudomonas fluorescens (two isolates), Bacillus subtilis (one isolate) and Pseudomonas sp. (one isolate)) or their volatiles showed antagonistic activity against most of the 10 plant pathogens in plate assays. Cell-free culture filtrates (CF) of five isolates or 1-butanol extracts of CFs also inhibited the growth of most pathogen mycelia in plate assays. PCR analysis confirmed the presence of most antibiotic biosynthetic genes such as phlD, phzFA, prnD and pltC in most Pseudomonas isolates and bmyB, bacA, ituD, srfAA and fenD in most Bacillus isolates. These bacterial isolates varied in the production of hydrogen cyanide (HCN), siderophores, β-1,3-glucanases, chitinases, proteases, indole-3-acetic acid, salicylic acid, and for nitrogen fixation and phosphate solubilization. Gas chromatography-mass spectrometry analysis identified 10 volatile compounds from 10 isolates and 18 compounds from 1-butanol extracts of CFs of five isolates. Application of irradiated peat formulation of six isolates to tomato roots prior to transplanting in a Forl-infested potting mix and field soil provided protection of tomato plants from FCRR disease and enhanced plant growth under greenhouse conditions. Five of the 13 indigenous bacterial isolates were antagonistic to eight plant pathogens, both in vitro and in vivo. Antagonistic and plant-growth promotion activities of these isolates might be related to the production of several types of antibiotics, lytic enzymes, phytohormones, secondary

  14. Bilaterally symmetric axes with rhizoids composed the rooting structure of the common ancestor of vascular plants.

    Science.gov (United States)

    Hetherington, Alexander J; Dolan, Liam

    2018-02-05

    There are two general types of rooting systems in extant land plants: gametophyte rhizoids and sporophyte root axes. These structures carry out the rooting function in the free-living stage of almost all land plant gametophytes and sporophytes, respectively. Extant vascular plants develop a dominant, free-living sporophyte on which roots form, with the exception of a small number of taxa that have secondarily lost roots. However, fossil evidence indicates that early vascular plants did not develop sporophyte roots. We propose that the common ancestor of vascular plants developed a unique rooting system-rhizoidal sporophyte axes. Here we present a synthesis and reinterpretation of the rootless sporophytes of Horneophyton lignieri , Aglaophyton majus , Rhynia gwynne-vaughanii and Nothia aphylla preserved in the Rhynie chert. We show that the sporophyte rooting structures of all four plants comprised regions of plagiotropic (horizontal) axes that developed unicellular rhizoids on their underside. These regions of axes with rhizoids developed bilateral symmetry making them distinct from the other regions which were radially symmetrical. We hypothesize that rhizoidal sporophyte axes constituted the rooting structures in the common ancestor of vascular plants because the phylogenetic positions of these plants span the origin of the vascular lineage.This article is part of a discussion meeting issue 'The Rhynie cherts: our earliest terrestrial ecosystem revisited'. © 2017 The Authors.

  15. Neurobiological roots of language in primate audition: common computational properties.

    Science.gov (United States)

    Bornkessel-Schlesewsky, Ina; Schlesewsky, Matthias; Small, Steven L; Rauschecker, Josef P

    2015-03-01

    Here, we present a new perspective on an old question: how does the neurobiology of human language relate to brain systems in nonhuman primates? We argue that higher-order language combinatorics, including sentence and discourse processing, can be situated in a unified, cross-species dorsal-ventral streams architecture for higher auditory processing, and that the functions of the dorsal and ventral streams in higher-order language processing can be grounded in their respective computational properties in primate audition. This view challenges an assumption, common in the cognitive sciences, that a nonhuman primate model forms an inherently inadequate basis for modeling higher-level language functions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Metabolite Profiling of Root Exudates of Common Bean under Phosphorus Deficiency

    Directory of Open Access Journals (Sweden)

    Keitaro Tawaraya

    2014-07-01

    Full Text Available Root exudates improve the nutrient acquisition of plants and affect rhizosphere microbial communities. The plant nutrient status affects the composition of root exudates. The purpose of this study was to examine common bean (Phaseolus vulgaris L. root exudates under phosphorus (P deficiency using a metabolite profiling technique. Common bean plants were grown in a culture solution at P concentrations of 0 (P0, 1 (P1 and 8 (P8 mg P L−1 for 1, 10 and 20 days after transplanting (DAT. Root exudates were collected, and their metabolites were determined by capillary electrophoresis time-of-flight mass spectrometry (CE-TOF MS. The shoot P concentration and dry weight of common bean plants grown at P0 were lower than those grown at P8. One hundred and fifty-nine, 203 and 212 metabolites were identified in the root exudates, and 16% (26/159, 13% (26/203 and 9% (20/212 of metabolites showed a P0/P8 ratio higher than 2.0 at 1, 10 and 20 DAT, respectively. The relative peak areas of several metabolites, including organic acids and amino acids, in root exudates were higher at P0 than at P8. These results suggest that more than 10% of primary and secondary metabolites are induced to exude from roots of common bean by P deficiency.

  17. 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

    2015-07-06

    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.

  18. Evaluation of microbial products for the control of zucchini foot and root rot caused by Fusarium solani f. sp. cucurbitae race 1

    Directory of Open Access Journals (Sweden)

    Roberta ROBERTI

    2012-09-01

    for an effective management of zucchini Fusarium foot and root rot through rhizosphere competence and several mechanisms exerted by their microbial ingredients.

  19. Studies on storage rot of cocoyam

    African Journals Online (AJOL)

    uc network

    42(3): 2059-2068. Eze, C.S (1984). Studies on storage rot of cocoyam (Colocasia esculenta (L.) Schott) at Nsukka. MSc. Dissertation, Dept of Botany, Univ of Nigeria, Nsukka. 73pp. Loyonga, S. N and Nzietchueng S. (1987). Cocoyam and African food crisi. In: Tropical Root Crops: Root crops and the African food crisis Terry ...

  20. Medical Terminology: Using Some Common Prefixes, Suffixes, and Roots. Health Occupations Education Module.

    Science.gov (United States)

    Temple Univ., Philadelphia, PA. Div. of Vocational Education.

    This module on medical terminology (using common prefixes, suffixes, and root words) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to the module topic, a list of resources needed, and three learning…

  1. Evidence for the endophytic colonization of Phaseolus vulgaris (common bean) roots by the diazotroph Herbaspirillum seropedicae.

    Science.gov (United States)

    Schmidt, M A; Souza, E M; Baura, V; Wassem, R; Yates, M G; Pedrosa, F O; Monteiro, R A

    2011-03-01

    Herbaspirillum seropedicae is an endophytic diazotrophic bacterium, which associates with important agricultural plants. In the present study, we have investigated the attachment to and internal colonization of Phaseolus vulgaris roots by the H. seropedicae wild-type strain SMR1 and by a strain of H. seropedicae expressing a red fluorescent protein (DsRed) to track the bacterium in the plant tissues. Two-day-old P. vulgaris roots were incubated at 30°C for 15 min with 6 x 10(8) CFU/mL H. seropedicae SMR1 or RAM4. Three days after inoculation, 4 x 10(4) cells of endophytic H. seropedicae SMR1 were recovered per gram of fresh root, and 9 days after inoculation the number of endophytes increased to 4 x 10(6) CFU/g. The identity of the recovered bacteria was confirmed by amplification and sequencing of the 16SrRNA gene. Furthermore, confocal microscopy of P. vulgaris roots inoculated with H. seropedicae RAM4 showed that the bacterial cells were attached to the root surface 15 min after inoculation; fluorescent bacteria were visible in the internal tissues after 24 h and were found in the central cylinder after 72 h, showing that H. seropedicae RAM4 is capable of colonizing the roots of the dicotyledon P. vulgaris. Determination of dry weight of common bean inoculated with H. seropedicae SMR1 suggested that this bacterium has a negative effect on the growth of P. vulgaris.

  2. Effect of composts on microbial dynamics and activity, dry root rot severity and seed yield of cowpea in the Indian arid region

    Directory of Open Access Journals (Sweden)

    Meenu BAREJA

    2011-01-01

    Full Text Available Nutrient-deficient sandy soil, having poor moisture retention, favors  Macrophomina phaseolina, a soil-borne plant pathogen, occurring in severe form on many important crops grown in the Indian arid region. In a 2-year field experiment, five composts (4 ton/ha prepared from residues of Calotropis procera, Prosopis juliflora, Azadirachta indica, Acacia nilotica, and on-farm weeds were tested on cowpea (Vigna unguiculata to determine their effectiveness in limiting the  severity of charcoal rot caused by M. phaseolina in relation to the microbial population dynamics, microbial activity and the seed yield of cowpea.  In general, compost-amended plots retained 8.9% higher moisture than unamended plots. The microbial population increased in amended plots during the crop season. Populations of total fungi and actinomycetes were heighest in Calotropis compost-amended soil, while total bacteria were maximum in weed- compost amended soil. Microbial activity in amended plots was  26.3% higher than in unamended plots. Among trace elements,  uptake of Zn, Mn, Fe and Cu was  heighest  in plants grown in weed-compost amended soil followed by A. nilotica compost-amended soil. Soil amendment with the composts significantly reduced  plant mortality due to charcoal rot. The lowest mortality was recorded in plants amended with A. nilotica compost (5.5% followed by P. juliflora compost (5.8, while the  highest plant mortality (11.5% from charcoal rot occurred in the unamended control on the basis of the pooled average of two years. There was a significant inverse correlation between microbial activity and charcoal rot incidence in cowpea at 20 days after planting. Composts also had a beneficial effect on yield, with a 28.3% increase in seed yield in P. juliflora compost-amended plots. These results suggest that in resource-deficient farming , certain on-farm wastes can be effectively utilized for managing soil-borne pathogens, as well as  for

  3. Root Canal Stripping: Malpractice or Common Procedural Accident-An Ethical Dilemma in Endodontics.

    Science.gov (United States)

    Ciobanu, Ionela Elisabeta; Rusu, Darian; Stratul, Stefan-Ioan; Didilescu, Andreea Cristina; Cristache, Corina Marilena

    2016-01-01

    Root canal stripping is defined as an oblong, vertical perforation that appears especially in the middle section of curved root canals during endodontic treatments with nickel-titanium (Ni-Ti) instruments. Its occurrence may drastically affect the outcome of the treatment, transforming a common otherwise efficient endodontic procedure into a complication such as tooth extraction. In order to discuss the ethical and legal consequences, two cases of dental strip perforations are herewith presented. Due to the existence of risk factors for dental strip perforation, experience of the clinician and the use of magnification and modern imagistic methods (CBCT) may avoid or reduce the frequency of this type of accidents. Under correct working circumstances, dental stripping should not be regarded as a malpractice but as a procedural accident. However, the patient must always be informed, before and during the endodontic procedure, about the event and the possible complications that may occur.

  4. Studies on black stain root disease in ponderosa pine. pp. 236-240. M. Garbelotto & P. Gonthier (Editors). Proceedings 12th International Conference on Root and Butt Rots of Forest Trees.

    Science.gov (United States)

    W. J. Otrosina; J. T. Kliejunas; S. S. Sung; S. Smith; D. R. Cluck

    2008-01-01

    Black stain root disease of ponderosa pine, caused by Lepfographium wageneri var. ponderosum (Harrington & Cobb) Harrington & Cobb, is increasing on many eastside pine stands in northeastern California. The disease is spread from tree to tree via root contacts and grafts but new infections are likely vectored by root...

  5. Variability of root traits in common bean genotypes at different levels of phosphorus supply and ontogenetic stages

    Directory of Open Access Journals (Sweden)

    Roberto dos Santos Trindade

    2014-08-01

    Full Text Available Selection of common bean (Phaseolus vulgaris L. cultivars with enhanced root growth would be a strategy for increasing P uptake and grain yield in tropical soils, but the strong plasticity of root traits may compromise their inclusion in breeding programs. The aim of this study was to evaluate the magnitude of the genotypic variability of root traits in common bean plants at two ontogenetic stages and two soil P levels. Twenty-four common bean genotypes, comprising the four growth habits that exist in the species and two wild genotypes, were grown in 4 kg pots at two levels of applied P (20 and 80 mg kg-1 and harvested at the stages of pod setting and early pod filling. Root area and root length were measured by digital image analysis. Significant genotype × P level and genotype × harvest interactions in analysis of variance indicate that the genotypic variation of root traits depended on soil nutrient availability and the stage at which evaluation was made. Genotypes differed for taproot mass, basal and lateral root mass, root area and root length at both P levels and growth stages; differences in specific root area and length were small. Genotypes with growth habits II (upright indeterminate and III (prostrate indeterminate showed better adaptation to limited P supply than genotypes of groups I (determinate and IV (indeterminate climbing. Between the two harvests, genotypes of groups II and III increased the mass of basal and lateral roots by 40 and 50 %, respectively, whereas genotypes of groups I and IV by only 7 and 19 %. Values of the genotypic coefficient of determination, which estimates the proportion of phenotypic variance resulting from genetic effects, were higher at early pod filling than at pod setting. Correlations between shoot mass and root mass, which could indicate indirect selection of root systems via aboveground biomass, were higher at early pod filling than at pod setting. The results indicate that selection for root

  6. 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)

    Yamakawa, K.; Yasui, H.; Mochizuki, T.; Hida, K.; Komochi, S.

    1987-01-01

    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

  7. Genetic analysis reveals efficient sexual spore dispersal at a fine spatial scale in Armillaria ostoyae, the causal agent of root-rot disease in conifers

    OpenAIRE

    Capedevielle, Xavier; Lung, Brigitte; Labbé, Frédéric; Dutech, Cyril; Lung-Escarmant, Brigitte

    2017-01-01

    Armillaria ostoyae (sometimes named A. solidipes) is a fungal species causing root diseases in numerous coniferous forests of the northern hemisphere. The importance of sexual spores for the establishment of new disease centers remains unclear, particularly in the large maritime pine plantations of southwestern France. An analysis of the genetic diversity of a local fungal population distributed over 500 ha in this French forest showed genetic recombination between genotypes to be frequent, c...

  8. Combined effect of soil amendment with oil cakes and seed priming in the control of root rot fungi of leguminous and non-leguminous crops

    International Nuclear Information System (INIS)

    Rafi, H.; Dawar, S.; Tariq, M.

    2016-01-01

    Organic amendments of soil help in proper aeration, rising of temperature and water holding capacity which results in better uptake of nutrients with root system gets extensive establishment. In this study, effects of soil amendment with oil seed cakes including mustard (Brassica campestris L.), cotton (Gossypium hirsutum L.), almond (Prunus amygdalus L.) and black seed (Nigella sativa L.) cakes at the rate of 0.1 and 1% w/w and priming of seeds with Acacia nilotica (L.) Willd. ex Delile and Sapindus mukorossi (L.) leaves extracts and microbial antagonists (Trichoderma harzianum and Rhizobium melilotii) was observed on the growth of plants and in the suppression of root infecting fungi. The results obtained showed that combined effect of bio-priming of seeds with T. harzianum spore suspension and amendment of soil with mustard cake at the rate of 1% was found to be most effective for the growth of leguminous and non-leguminous crop plants (peanut, chickpea, okra and sunflower) and for the reduction of root infecting fungi like Macrophomina phaseolina, Fusarium spp followed by R. meliloti primed seeds in combination with cotton, almond and black seed cakes amendment respectively as compared to control (non treated seeds and soil). (author)

  9. CERN and ESA’s common roots to fly into space

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    ESA has named a space ferry after Edoardo Amaldi, one of the founding fathers of CERN but also of ESRO, the ancestor of ESA. Although they have developed in different ways, the three large European scientific organisations – CERN, ESO and ESA – have common roots. A webcast on the day of the launch of the spaceship from Kourou (French Guiana) will celebrate this fact with historic recollections and the participation of members of the Amaldi family.   The ESA’s Automated Transfer Vehicle (ATV) number three will fly a document which has a very clear title: “Edoardo Amaldi, an ESA pioneer”. Given the fact that Edoardo Amaldi was also one of the founding fathers of CERN and that CERN gave birth to ESO, the idea to mark the event with a common action came quite naturally. The live webcast will take place on 23 March at 3 p.m. with the participation of Ugo Amaldi, CERN physicist and son of Edoardo Amaldi, Arturo Russo, historian and author with John...

  10. 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.

  11. Heterobasidion annosum root and butt rot of Norway spruce, Picea abies: Colonization by the fungus and its impact on tree growth

    Energy Technology Data Exchange (ETDEWEB)

    Bendz-Hellgren, M. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    1997-12-31

    Diameter growth losses associated with decay were quantified on a nationwide scale, and volume growth losses were measured in two stands. Diameter growth losses were 8-10% during a 5-year period in the nationwide study and 23% in one of the stands, whereas in the other stand, no volume losses could be attributed to decay. The effects of stump moisture content, temperature and time elapsed between felling and inoculation on the establishment of H. annosum spore infections in stumps were investigated among stumps resulting from thinnings and clear-cuttings. Furthermore, inoculations with H. annosum conidia were made between 0 hours and 4 weeks after thinning. The incidence of stump infections was lower on clear-cut areas than in thinned stands, but high enough to warrant stump treatment on clear-cuttings. A positive relation was found between heartwood moisture content and the proportion of heartwood infected, whereas the opposite relation was found for sapwood. The establishment of new conidiospore infections decreased with time, and it appeared that stumps were no longer susceptible to infection after 3 weeks had elapsed since felling. Roots of stumps and trees on forest land or former arable land were inoculated with H. annosum treated sawdust. The growth rate of H. annosum in roots of stumps was 25 cm/year, corresponding to 2.5 to 3 times the growth rate in tree roots. Previous land use did not affect the fungal rate of spread. Also, the average initial spread rate of H. annosum in naturally infected Norway spruce stems was estimated at 30 cm/year 156 refs, 9 figs

  12. Common cause failure: enhancing defenses against root cause and coupling factor

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Poorva; Kim, Sok Chul [KINS, Daejeon (Korea, Republic of)

    2016-10-15

    A Common Cause Failure(CCF) event refers to a specific class of dependent events that result from co-existence of two main factors: Susceptibility of components to fail or become unavailable due to particular root cause of failure, and coupling factor coupling mechanism) that creates the condition for multiple components getting affected. PSA (Probabilistic Safety Assessment) operating experience of Nuclear Power Plants have demonstrated that dependent events such as CCF events are major contributor to risk during operation. From cost-benefit consideration, putting significant design modifications in place to prevent CCF would not be desirable in terms of risk management regulatory effectiveness and efficiency. The aim of this study was to propose feasible defenses against CCF from cost benefit consideration to enhance the safety. This study provides the CDM and CFDM of EDG. Defenses employed against cause and coupling factor can be easily employed in operation and maintenance programme of NPP and are not an additional cost burden. Such enhancement of defense against the CCF can give a modest improvement in CDF. This approach is specifically helpful in plants that are already under operation and significant modifications are not economically feasible.

  13. Physiological minimum temperatures for root growth in seven common European broad-leaved tree species.

    Science.gov (United States)

    Schenker, Gabriela; Lenz, Armando; Körner, Christian; Hoch, Günter

    2014-03-01

    Temperature is the most important factor driving the cold edge distribution limit of temperate trees. Here, we identified the minimum temperatures for root growth in seven broad-leaved tree species, compared them with the species' natural elevational limits and identified morphological changes in roots produced near their physiological cold limit. Seedlings were exposed to a vertical soil-temperature gradient from 20 to 2 °C along the rooting zone for 18 weeks. In all species, the bulk of roots was produced at temperatures above 5 °C. However, the absolute minimum temperatures for root growth differed among species between 2.3 and 4.2 °C, with those species that reach their natural distribution limits at higher elevations also tending to have lower thermal limits for root tissue formation. In all investigated species, the roots produced at temperatures close to the thermal limit were pale, thick, unbranched and of reduced mechanical strength. Across species, the specific root length (m g(-1) root) was reduced by, on average, 60% at temperatures below 7 °C. A significant correlation of minimum temperatures for root growth with the natural high elevation limits of the investigated species indicates species-specific thermal requirements for basic physiological processes. Although these limits are not necessarily directly causative for the upper distribution limit of a species, they seem to belong to a syndrome of adaptive processes for life at low temperatures. The anatomical changes at the cold limit likely hint at the mechanisms impeding meristematic activity at low temperatures.

  14. Genetic analysis reveals efficient sexual spore dispersal at a fine spatial scale in Armillaria ostoyae, the causal agent of root-rot disease in conifers.

    Science.gov (United States)

    Dutech, Cyril; Labbé, Frédéric; Capdevielle, Xavier; Lung-Escarmant, Brigitte

    Armillaria ostoyae (sometimes named Armillaria solidipes) is a fungal species causing root diseases in numerous coniferous forests of the northern hemisphere. The importance of sexual spores for the establishment of new disease centres remains unclear, particularly in the large maritime pine plantations of southwestern France. An analysis of the genetic diversity of a local fungal population distributed over 500 ha in this French forest showed genetic recombination between genotypes to be frequent, consistent with regular sexual reproduction within the population. The estimated spatial genetic structure displayed a significant pattern of isolation by distance, consistent with the dispersal of sexual spores mostly at the spatial scale studied. Using these genetic data, we inferred an effective density of reproductive individuals of 0.1-0.3 individuals/ha, and a second moment of parent-progeny dispersal distance of 130-800 m, compatible with the main models of fungal spore dispersal. These results contrast with those obtained for studies of A. ostoyae over larger spatial scales, suggesting that inferences about mean spore dispersal may be best performed at fine spatial scales (i.e. a few kilometres) for most fungal species. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  15. Antifungal Effects Of Botanical Leaf Extracts On Tuber Rots Of Yam ...

    African Journals Online (AJOL)

    The fungicidal effects of dry and fresh leaf extracts of Axardirachta indica (L) and Ocimum grattissimum on the rot of yam tubers were investigated. Fusaruim oxysporium, Rhjzopus stolonifer, Botryodiplodia theobromae and Aspergillus Niger (root pathogens) were isolated from the rotted yam. Both dry and fresh leaf extracts ...

  16. Evidence for the endophytic colonization of Phaseolus vulgaris(common bean roots by the diazotroph Herbaspirillum seropedicae

    Directory of Open Access Journals (Sweden)

    M.A. Schmidt

    2011-03-01

    Full Text Available Herbaspirillum seropedicae is an endophytic diazotrophic bacterium, which associates with important agricultural plants. In the present study, we have investigated the attachment to and internal colonization of Phaseolus vulgaris roots by the H. seropedicae wild-type strain SMR1 and by a strain of H. seropedicae expressing a red fluorescent protein (DsRed to track the bacterium in the plant tissues. Two-day-old P. vulgaris roots were incubated at 30°C for 15 min with 6 x 10(8 CFU/mL H. seropedicae SMR1 or RAM4. Three days after inoculation, 4 x 10(4 cells of endophytic H. seropedicae SMR1 were recovered per gram of fresh root, and 9 days after inoculation the number of endophytes increased to 4 x 10(6 CFU/g. The identity of the recovered bacteria was confirmed by amplification and sequencing of the 16SrRNA gene. Furthermore, confocal microscopy of P. vulgaris roots inoculated with H. seropedicae RAM4 showed that the bacterial cells were attached to the root surface 15 min after inoculation; fluorescent bacteria were visible in the internal tissues after 24 h and were found in the central cylinder after 72 h, showing that H. seropedicae RAM4 is capable of colonizing the roots of the dicotyledon P. vulgaris. Determination of dry weight of common bean inoculated with H. seropedicae SMR1 suggested that this bacterium has a negative effect on the growth of P. vulgaris.

  17. 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

  18. Isolation of symlandine from the roots of common comfrey (Symphytum officinale) using countercurrent chromatography.

    Science.gov (United States)

    Kim, N C; Oberlies, N H; Brine, D R; Handy, R W; Wani, M C; Wall, M E

    2001-02-01

    Three pyrrolizidine alkaloids, symlandine, symphytine, and echimidine (1-3), were isolated from the roots of Symphytum officinale using a one-step countercurrent chromatography procedure. The structures of 1-3 were confirmed by several spectroscopic techniques including 2D NMR methods. This is the first description of the separation of symlandine (1) from its stereoisomer, symphytine (2).

  19. Hairy root transgene expression analysis of a secretory peroxidase (PvPOX1) from common bean infected by Fusarium wilt.

    Science.gov (United States)

    Xue, Renfeng; Wu, Xingbo; Wang, Yingjie; Zhuang, Yan; Chen, Jian; Wu, Jing; Ge, Weide; Wang, Lanfen; Wang, Shumin; Blair, Matthew W

    2017-07-01

    Plant peroxidases (POXs) are one of the most important redox enzymes in the defense responses. However, the large number of different plant POX genes makes it necessary to carefully confirm the function of each paralogous POX gene in specific tissues and disease interactions. Fusarium wilt is a devastating disease of common bean caused by Fusarium oxysporum f. sp. phaseoli. In this study, we evaluated a peroxidase gene, PvPOX1, from a resistant common bean genotype, CAAS260205 and provided direct evidence for PvPOX1's role in resistance by transforming the resistant allele into a susceptible common bean genotype, BRB130, via hairy root transformation using Agrobacterium rhizogenes. Analysis of PvPOX1 gene over-expressing hairy roots showed it increased resistance to Fusarium wilt both in the roots and the rest of transgenic plants. Meanwhile, the PvPOX1 expressive level, the peroxidase activity and hydrogen peroxide (H 2 O 2 ) accumulation were also enhanced in the interaction. The result showed that the PvPOX1 gene played an essential role in Fusarium wilt resistance through the occurrence of reactive oxygen species (ROS) induced hypersensitive response. Therefore, PvPOX1 expression was proven to be a valuable gene for further analysis which can strengthen host defense response against Fusarium wilt through a ROS activated resistance mechanism. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Thickening of the cauda equina roots: a common finding in Krabbe disease

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Misun; Rodriguez, David [Department of Radiology of University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Zuccoli, Giulio; Panigrahy, Ashok [Section of Neuroradiology, Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Poe, Michele D.; Escolar, Maria L. [Department of Pediatrics at Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, PA (United States)

    2016-10-15

    Evaluation of Krabbe disease burden and eligibility for hematopoietic stem cell transplantation are often based on neuroimaging findings using the modified Loes scoring system, which encompasses central but not peripheral nervous system changes. We show that quantitative evaluation of thickened cauda equina nerve roots may improve the evaluation of Krabbe disease and therapeutic guidance. Lumbar spine MRI scans of patients obtained between March 2013 and September 2013 were retrospectively evaluated and compared to those of controls. Quantitative evaluation of cauda equina roots was performed on the axial plane obtained approximately 5 mm below the conus medullaris. The largest nerves in the right and left anterior quadrants of the spinal canal were acquired. Fifteen symptomatic patients with Krabbe disease (5-44 months old) and eleven age-matched controls were evaluated. The average areas (mm{sup 2}) of anterior right and left nerves were 1.40 and 1.23, respectively, for patients and 0.61 and 0.60 for controls (differences: 0.79 and 0.63; p < 0.001). Cauda equina nerve root thickening is associated with Krabbe disease in both treated and untreated patients. Adding lumbar spine MRI to the current neurodiagnostic protocols, which fails to account for peripheral nerve abnormalities, will likely facilitate the diagnosis of Krabbe disease. (orig.)

  1. 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.

  2. Impact of management strategies in the basal rot, charcoal rots epidemiology and Phaseolus vulgaris L. yield.

    Directory of Open Access Journals (Sweden)

    Ulacio Osorio Dilcia

    2013-02-01

    Full Text Available The effect of chemical, physical, biologycal and cultural strategies individually or combinated were evaluated in the epidemiology of the basal rot (Sclerotium rolfsii, charcoal rot (Macrophomina phaseolina and the Phaseolus vulgaris cv Tacarigua yield at Barinas state from Venezuela. In the experiment, Tebuconazole (Teb was applicated at seed (1 L/Ton and at soil, a los 30 y 60 days after of the sow (1 L/ha; Trichoderma harzianum (Tri was applicated at seed (15 g for each 1.5 k and to 15, 30, 45 y 60 days after of the sow (30 g/10 L of water. On the other hand, soil was solarizated (Sol during 15 days and calcium nitrate (Ca (60 g/10 L of water was applicated each 15 days until 60 days of growth of cultivated plants. Basal rot was registered as far as 42 days after of the sow, showing less of 5.3% in Teb y the combination SolTeb. The hightest incidence of this disease was observed in the treatment Tri with 28.5%, being highter that control (14.5%. Last to 42 days predominated the charcoal rot in the rest of the plants for a total of 100% of incidente in everything the treatments. Nevertheless, Teb showed the hightest yield with 555 k/ha, being different estatistically at treatment TriCa, which showed the lowest yield with 31 k/ha, however, the roots not formed nodules nitrogen uptake in these replications with the fungicide and Ca. It is concluded that S. rolfsii was sensible at action of some of the treatments; but not M. phaseolina; nevertheless, the plants were capables to produce seeds health apparently in treatments in which observed less severity of charcoal rot.

  3. Identification of microRNAs in Response to Drought in Common Wild Rice (Oryza rufipogon Griff.) Shoots and Roots.

    Science.gov (United States)

    Zhang, Jing-Wen; Long, Yan; Xue, Man-de; Xiao, Xing-Guo; Pei, Xin-Wu

    2017-01-01

    Drought is the most important factor that limits rice production in drought-prone environments. Plant microRNAs (miRNAs) are involved in biotic and abiotic stress responses. Common wild rice (Oryza rufipogon Griff.) contains abundant drought-resistant genes, which provide an opportunity to explore these excellent resources as contributors to improve rice resistance, productivity, and quality. In this study, we constructed four small RNA libraries, called CL and CR from PEG6000-free samples and DL and DR from PEG6000-treated samples, where 'R' indicates the root tissue and 'L' indicates the shoot tissue. A total of 200 miRNAs were identified to be differentially expressed under the drought-treated conditions (16% PEG6000 for 24 h), and the changes in the miRNA expression profile of the shoot were distinct from those of the root. At the miRNA level, 77 known miRNAs, which belong to 23 families, including 40 up-regulated and 37 down-regulated in the shoot, and 85 known miRNAs in 46 families, including 65 up-regulated and 20 down-regulated in the root, were identified as differentially expressed. In addition, we predicted 26 new miRNA candidates from the shoot and 43 from the root that were differentially expressed during the drought stress. The quantitative real-time PCR analysis results were consistent with high-throughput sequencing data. Moreover, 88 miRNAs that were differentially-expressed were predicted to match with 197 targets for drought-stress. Our results suggest that the miRNAs of O. rufipogon are responsive to drought stress. The differentially expressed miRNAs that are tissue-specific under drought conditions could play different roles in the regulation of the auxin pathway, the flowering pathway, the drought pathway, and lateral root formation. Thus, the present study provides an account of tissue-specific miRNAs that are involved in the drought adaption of O. rufipogon.

  4. Evaluation and Selection of Common Bean (Phaseolus Vulgaris L.) Genotypes for Root Traits Associated with Phosphorus (P) Acquisition Efficiency and the Use of {sup 32}P Isotope in Studies on P Uptake by Root Hairs

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, M. A.; Jochua, C. [Agricultural Research Institute of Mozambique (IIAM), Maputo (Mozambique); Lynch, J. P. [Pennsylvania State University, University Park, PA (United States)

    2013-11-15

    Low phosphorus (P) availability is one of the main edaphic constraints limiting crop production and productivity in most of the tropical agro-ecosystems. Several root traits are known to be associated with P acquisition efficiency in low P soils. These root traits include root hairs. Computer modeling, laboratory and field studies show the depletion of {sup 32}P-phosphate around roots and that the depletion zone is influenced by the length and density of root hairs. We conducted a study involving a series of experiments with the objective of evaluating the variability of root traits associated with P uptake efficiency among common bean (Phaseolus vulgaris L.) genotypes, and to understand the mechanisms of long root hairs leading to the increase in P uptake in common bean. The study included (a) the screening of common bean genotypes in the laboratory and in the field for root traits, and (b) the use of radioactive phosphorus ({sup 32}P) in the experiments conducted in the greenhouse. For laboratory screening, seedlings were germinated in paper rolls in a growth media for 3 days before evaluation for basal root whorl number (BRWN), basal root number (BRN), basal root growth angle (BRGA) and root hair length (RHL). Common bean genotypes were planted in the field with low P for 45 days after planting (DAP) before evaluation. For the {sup 32}P study four contrasting genotypes for root hairs were grown for 28 DAP in the greenhouse using 15-20 liter pots filled with a mixture of sand and vermiculate as the growth media. The radioactive P was incorporated in the growth medium in the form of alumina-P fertilizer. Normal phosphorus (non-radioactive {sup 31}P) was included in the nutrient solution in the form of calcium phosphate, Ca{sub 3}(PO{sub 4}){sub 2}, and supplied through irrigation. Screened genotypes exhibited different root traits associated with P uptake efficiency, and that a given genotype can have one or more root traits responsible for it P uptake efficiency

  5. Characterizing butt-rot fungi on USA-affiliated islands in the western Pacific

    Science.gov (United States)

    Phil Cannon; Ned B. Klopfenstein; Robert L. Schlub; Mee-Sook Kim; Yuko Ota; Norio Sahashi; Roland J. Quitugua; John W. Hanna; Amy L. Ross-Davis; J. D. Sweeney

    2014-01-01

    Ganoderma and Phellinus are genera that commonly cause tree butt-rot on USA-affiliated islands of the western Pacific. These fungal genera can be quite prevalent, especially in older mangrove stands. Although the majority of infections caused by these fungi lead to severe rotting of the heartwood, they typically do not directly kill the living tissues of the sapwood,...

  6. Common neural structures activated by epidural and transcutaneous lumbar spinal cord stimulation: Elicitation of posterior root-muscle reflexes.

    Directory of Open Access Journals (Sweden)

    Ursula S Hofstoetter

    Full Text Available Epidural electrical stimulation of the lumbar spinal cord is currently regaining momentum as a neuromodulation intervention in spinal cord injury (SCI to modify dysregulated sensorimotor functions and augment residual motor capacity. There is ample evidence that it engages spinal circuits through the electrical stimulation of large-to-medium diameter afferent fibers within lumbar and upper sacral posterior roots. Recent pilot studies suggested that the surface electrode-based method of transcutaneous spinal cord stimulation (SCS may produce similar neuromodulatory effects as caused by epidural SCS. Neurophysiological and computer modeling studies proposed that this noninvasive technique stimulates posterior-root fibers as well, likely activating similar input structures to the spinal cord as epidural stimulation. Here, we add a yet missing piece of evidence substantiating this assumption. We conducted in-depth analyses and direct comparisons of the electromyographic (EMG characteristics of short-latency responses in multiple leg muscles to both stimulation techniques derived from ten individuals with SCI each. Post-activation depression of responses evoked by paired pulses applied either epidurally or transcutaneously confirmed the reflex nature of the responses. The muscle responses to both techniques had the same latencies, EMG peak-to-peak amplitudes, and waveforms, except for smaller responses with shorter onset latencies in the triceps surae muscle group and shorter offsets of the responses in the biceps femoris muscle during epidural stimulation. Responses obtained in three subjects tested with both methods at different time points had near-identical waveforms per muscle group as well as same onset latencies. The present results strongly corroborate the activation of common neural input structures to the lumbar spinal cord-predominantly primary afferent fibers within multiple posterior roots-by both techniques and add to unraveling the

  7. Field Efficiency Trial of 72% Streptomycin against Konjac Bacterial Soft Rot

    Institute of Scientific and Technical Information of China (English)

    Huang; Yongsheng; Li; Xiaojun; Zhu; Shijin; Ma; Yongsheng; Wang; Li

    2014-01-01

    72% Streptomycin soluble powder was used to control konjac bacterial soft rot in the study. The control efficiency and yield of different treatments were investigated,and the benefit was analyzed. The control scheme against konjac bacterial soft rot was as follows: spraying 72% atreptomycinon twice on rotation fields after all the seedlings were strong and uniform,or irrigating roots with 72% atreptomycinon once and spraying twice on continuous cropping fields.

  8. The moment magnitude M w and the energy magnitude M e: common roots and differences

    Science.gov (United States)

    Bormann, Peter; di Giacomo, Domenico

    2011-04-01

    Starting from the classical empirical magnitude-energy relationships, in this article, the derivation of the modern scales for moment magnitude M w and energy magnitude M e is outlined and critically discussed. The formulas for M w and M e calculation are presented in a way that reveals, besides the contributions of the physically defined measurement parameters seismic moment M 0 and radiated seismic energy E S, the role of the constants in the classical Gutenberg-Richter magnitude-energy relationship. Further, it is shown that M w and M e are linked via the parameter Θ = log( E S/ M 0), and the formula for M e can be written as M e = M w + (Θ + 4.7)/1.5. This relationship directly links M e with M w via their common scaling to classical magnitudes and, at the same time, highlights the reason why M w and M e can significantly differ. In fact, Θ is assumed to be constant when calculating M w. However, variations over three to four orders of magnitude in stress drop Δ σ (as well as related variations in rupture velocity V R and seismic wave radiation efficiency η R) are responsible for the large variability of actual Θ values of earthquakes. As a result, for the same earthquake, M e may sometimes differ by more than one magnitude unit from M w. Such a difference is highly relevant when assessing the actual damage potential associated with a given earthquake, because it expresses rather different static and dynamic source properties. While M w is most appropriate for estimating the earthquake size (i.e., the product of rupture area times average displacement) and thus the potential tsunami hazard posed by strong and great earthquakes in marine environs, M e is more suitable than M w for assessing the potential hazard of damage due to strong ground shaking, i.e., the earthquake strength. Therefore, whenever possible, these two magnitudes should be both independently determined and jointly considered. Usually, only M w is taken as a unified magnitude in many

  9. Purification and characterization of an alkaline phosphatase induced by phosphorus starvation in common bean (Phaseolus vulgaris L.) roots

    Energy Technology Data Exchange (ETDEWEB)

    Morales, L.; Gutierrez, N.; Maya, V.; Parra, C.; Martinez B, E.; Coello, P., E-mail: pcoello@servidor.unam.mx [UNAM, Facultad de Quimica, Departamento de Bioquimica, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2012-07-01

    Two phosphatase isoforms from roots of the common bean (Phaseolus vulgaris L.) showed an increase in activity in response to phosphate deficiency. One of them (APIII) was chosen for further purification through ionic exchange chromatography and preparative electrophoresis. The estimated molecular mass of APIII was 35 kDa by both SDS-Page and gel filtration analyses, suggesting a monomeric form of the active enzyme. The phosphatase was classified as an alkaline phosphatase based on the requirement of ph 8 for optimum catalysis. It not only exhibited broad substrate specificity, with the most activity against pyrophosphate, but also effectively catalyzed the hydrolysis of polyphosphate, glucose-1-phosphate and phospho enol-pyruvate. Activity was completely inhibited by molybdate, vanadate and phosphate but was only partially inhibited by fluoride. Although divalent cations were not essential for the pyro phosphatase activity of this enzyme, the hydrolysis of pyro phosphatase increased substantially in the presence of Mg{sup 2+}.

  10. Purification and characterization of an alkaline phosphatase induced by phosphorus starvation in common bean (Phaseolus vulgaris L.) roots

    International Nuclear Information System (INIS)

    Morales, L.; Gutierrez, N.; Maya, V.; Parra, C.; Martinez B, E.; Coello, P.

    2012-01-01

    Two phosphatase isoforms from roots of the common bean (Phaseolus vulgaris L.) showed an increase in activity in response to phosphate deficiency. One of them (APIII) was chosen for further purification through ionic exchange chromatography and preparative electrophoresis. The estimated molecular mass of APIII was 35 kDa by both SDS-Page and gel filtration analyses, suggesting a monomeric form of the active enzyme. The phosphatase was classified as an alkaline phosphatase based on the requirement of ph 8 for optimum catalysis. It not only exhibited broad substrate specificity, with the most activity against pyrophosphate, but also effectively catalyzed the hydrolysis of polyphosphate, glucose-1-phosphate and phospho enol-pyruvate. Activity was completely inhibited by molybdate, vanadate and phosphate but was only partially inhibited by fluoride. Although divalent cations were not essential for the pyro phosphatase activity of this enzyme, the hydrolysis of pyro phosphatase increased substantially in the presence of Mg 2+ .

  11. Effect of phosphate and the arbuscular mycorrhizal fungus Glomus intraradices on disease severity of root rot of peas ( Pisum sativum ) caused by Aphanomyces euteiches

    DEFF Research Database (Denmark)

    Bødker, Lars; Kjøller, Rasmus; Rosendahl, Søren

    1998-01-01

    The effects of inorganic phosphate levels and the presence of arbuscular mycorrhiza on disease severity of Aphanomyces euteiches in pea roots were studied. Disease severity on roots and epicotyl as well as the oospore number within infected root tissue were correlated with the phosphorus (P) level...... to measure the activity of the pathogen in roots. The enzyme activity increased with disease severity and disease incidence, except in plants supplemented with P at the highest level, where a peak in activity was seen 12 days after inoculation with the pathogen, followed by a decrease in activity...

  12. The bean rhizosphere Pseudomonas aeruginosa strain RZ9 strongly reduces Fusarium culmorum growth and infectiveness of plant roots

    Energy Technology Data Exchange (ETDEWEB)

    Haddoudi, I.; Sendi, Y.; Batnini, M.; Romdhane, S.B.; Mhadhbi, H.; Mrabet, M.

    2017-07-01

    A faba bean rhizospheric Pseudomonas aeruginosa isolate RZ9 was used for studying its antifungal activity and protecting effects of faba bean and common bean against the root pathogen Fusarium culmorum strain MZB47. The dual culture tests showed that RZ9 inhibits MZB47 in vitro growth by 56%. When mixing RZ9 cell suspension with MZB47 macroconidia at equal proportion, the macroconidia viability was reduced with 70%. Pathogenicity tests conducted in sterile conditions showed that MZB47 caused an intense root rotting in faba bean ‘Aquadulce’ plantlets and a slight level in common bean ‘Coco blanc’. This was associated to significant decreases in plant growth only in ‘Aquadulce’, reducing shoot dry weight (DW) by 82% and root DW by 70%. In soil samples, MZB47 caused severe root rotting and induced significant decreases in shoot DW (up to 51%) and root DW (up to 60%) for both beans. It was associated to a decrease in nodule number by 73% and 52% for faba bean and common bean, respectively. Biocontrol assays revealed that the inoculation of RZ9 to MZB47-treated plantlets enhanced shoot DWs (25% and 110%) and root DWs (29% and 67%), in faba bean and common bean, respectively. Moreover, root rotting levels decreased and nodule number increased in treated compared to untreated plantlets. Collected data highlighted the disease severity of F. culmorum and demonstrated the potential of using RZ9 in controlling Fusaria root diseases in beans. Thereby, the current study represents the first report on the biocontrol effectiveness of P. aeruginosa against F. culmorum in beans.

  13. The bean rhizosphere Pseudomonas aeruginosa strain RZ9 strongly reduces Fusarium culmorum growth and infectiveness of plant roots

    Directory of Open Access Journals (Sweden)

    Imen Haddoudi

    2017-07-01

    Full Text Available A faba bean rhizospheric Pseudomonas aeruginosa isolate RZ9 was used for studying its antifungal activity and protecting effects of faba bean and common bean against the root pathogen Fusarium culmorum strain MZB47. The dual culture tests showed that RZ9 inhibits MZB47 in vitro growth by 56%. When mixing RZ9 cell suspension with MZB47 macroconidia at equal proportion, the macroconidia viability was reduced with 70%. Pathogenicity tests conducted in sterile conditions showed that MZB47 caused an intense root rotting in faba bean ‘Aquadulce’ plantlets and a slight level in common bean ‘Coco blanc’. This was associated to significant decreases in plant growth only in ‘Aquadulce’, reducing shoot dry weight (DW by 82% and root DW by 70%. In soil samples, MZB47 caused severe root rotting and induced significant decreases in shoot DW (up to 51% and root DW (up to 60% for both beans. It was associated to a decrease in nodule number by 73% and 52% for faba bean and common bean, respectively. Biocontrol assays revealed that the inoculation of RZ9 to MZB47-treated plantlets enhanced shoot DWs (25% and 110% and root DWs (29% and 67%, in faba bean and common bean, respectively. Moreover, root rotting levels decreased and nodule number increased in treated compared to untreated plantlets. Collected data highlighted the disease severity of F. culmorum and demonstrated the potential of using RZ9 in controlling Fusaria root diseases in beans. Thereby, the current study represents the first report on the biocontrol effectiveness of P. aeruginosa against F. culmorum in beans.

  14. Estimating the absorptive root area in Norway spruce by using the common direct and indirect earth impedance methods

    Czech Academy of Sciences Publication Activity Database

    Čermák, J.; Cudlín, Pavel; Gebauer, R.; Borja, I.; Martinková, M.; Staněk, Z.; Koller, J.; Neruda, J.; Nadezhdina, N.

    2013-01-01

    Roč. 372, 1-2 (2013), s. 401-415 ISSN 0032-079X R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŠk OC10023 Institutional support: RVO:67179843 Keywords : Active absorptive fine root area index * Fine root surface * Modified earth impedance * Picea abies * Root research methods Subject RIV: EH - Ecology, Behaviour Impact factor: 3.235, year: 2013

  15. Common and distinguishing features of the bacterial and fungal communities in biological soil crusts and shrub root zone soils

    Science.gov (United States)

    Steven, Blaire; Gallegos-Graves, La Verne; Yeager, Chris; Belnap, Jayne; Kuske, Cheryl R.

    2013-01-01

    Soil microbial communities in dryland ecosystems play important roles as root associates of the widely spaced plants and as the dominant members of biological soil crusts (biocrusts) colonizing the plant interspaces. We employed rRNA gene sequencing (bacterial 16S/fungal large subunit) and shotgun metagenomic sequencing to compare the microbial communities inhabiting the root zones of the dominant shrub, Larrea tridentata (creosote bush), and the interspace biocrusts in a Mojave desert shrubland within the Nevada Free Air CO2 Enrichment (FACE) experiment. Most of the numerically abundant bacteria and fungi were present in both the biocrusts and root zones, although the proportional abundance of those members differed significantly between habitats. Biocrust bacteria were predominantly Cyanobacteria while root zones harbored significantly more Actinobacteria and Proteobacteria. Pezizomycetes fungi dominated the biocrusts while Dothideomycetes were highest in root zones. Functional gene abundances in metagenome sequence datasets reflected the taxonomic differences noted in the 16S rRNA datasets. For example, functional categories related to photosynthesis, circadian clock proteins, and heterocyst-associated genes were enriched in the biocrusts, where populations of Cyanobacteria were larger. Genes related to potassium metabolism were also more abundant in the biocrusts, suggesting differences in nutrient cycling between biocrusts and root zones. Finally, ten years of elevated atmospheric CO2 did not result in large shifts in taxonomic composition of the bacterial or fungal communities or the functional gene inventories in the shotgun metagenomes.

  16. Characterizing forest root‐ and butt‐rot fungi in Yap, Palau, Pohnpei, Kosrae, Guam and Saipan [Chapter III

    Science.gov (United States)

    Phil Cannon; Ned B. Klopfenstein; Mee-Sook Kim; Yuko Ota; Norio Sahashi; Robert L. Schlub; Roger Brown; Sara M. Ashiglar; Amy L. Ross-Davis; John W. Hanna

    2014-01-01

    Ganoderma and Phellinus are two common fungal genera causing butt-rot on trees growing on USA-affiliated islands of the western Pacific. Although these fungi can be quite prevalent, especially in some older mangrove stands, it appears that the majority of infections caused by these fungi leads to severe rotting of the heartwood but do not kill the living...

  17. Opportunities for addressing laminated root rot caused by Phellinus sulphuracens in Washington's forests: A Report from the Washington State Academy of Sciences in cooperation with the Washington State Department of Natural Resources

    Science.gov (United States)

    R. James Cook; Robert L. Edmonds; Ned B. Klopfenstein; Willis Littke; Geral McDonald; Daniel Omdahl; Karen Ripley; Charles G. Shaw; Rona Sturrock; Paul Zambino

    2013-01-01

    This report from the Washington State Academy of Sciences (WSAS) is in response to a request from the Washington State Department of Natural Resources (DNR) to "identify approaches and opportunities ripe for research on understanding and managing root diseases of Douglas-fir." Similar to the process used by the National Research Council, the WSAS upon...

  18. Common symbiosis genes CERBERUS and NSP1 provide additional insight into the establishment of arbuscular mycorrhizal and root nodule symbioses in Lotus japonicus.

    Science.gov (United States)

    Nagae, Miwa; Takeda, Naoya; Kawaguchi, Masayoshi

    2014-01-01

    Arbuscular mycorrhizal symbiosis (AMS) and root nodule symbiosis (RNS) share several common symbiotic components, and many of the common symbiosis mutants block the entry of symbionts into the roots. We recently reported that CERBERUS (an E3 ubiquitin ligase) and NSP1 (a GRAS family transcription factor), required for RNS, also modulate AMS development in Lotus japonicus. The novel common symbiosis mutants, cerberus and nsp1, have low colonization of arbuscular mycorrhiza (AM) fungi, caused by a defect in internal hyphal elongation and by a decreased fungal entry into the roots, respectively. Here, we showed that CERBERUS was induced at the sites of symbiotic fungal or bacterial infection. NSP1 has been implicated in a strigolactone biosynthesis gene DWARF27 expression. Nevertheless, in nsp1, DWARF27 was induced by inoculation with AM fungi, implying the existence of a NSP1-independent regulatory mechanism of strigolactone biosynthesis during AMS establishment. These results support functional analysis of CERBERUS and NSP1, and also contribute to elucidation of common mechanisms in AMS and RNS.

  19. Cytotoxicity evaluation of a copaiba oil-based root canal sealer compared to three commonly used sealers in endodontics

    Science.gov (United States)

    Garrido, Angela Delfina Bittencourt; de Cara, Sueli Patricia Harumi Miyagi; Marques, Marcia Martins; Sponchiado, Emílio Carlos; Garcia, Lucas da Fonseca Roberti; de Sousa-Neto, Manoel Damião

    2015-01-01

    Background: The constant development of new root canal sealers has allowed the solution of a large number of clinical cases in endodontics, however, cytotoxicity of such sealers must be tested before their validation as filling materials. The aim of this study was to evaluate the cytotoxic effect of a new Copaiba oil-based root canal sealer (Biosealer [BS]) on osteoblast-like Osteo-1 cells. Materials and Methods: The experimental groups were formed according to the culture medium conditioned with the tested sealers, as follows: Control group (CG) (culture medium without conditioning); Sealer 26 (S26) - culture medium + S26; Endofill (EF) - culture medium + EF; AH Plus (AHP) - culture medium + AHP; and BS - culture medium + BS (Copaiba oil-based sealer). The conditioned culture medium was placed in contact with 2 × 104 cells cultivated on 60 mm diameter Petri dishes for 24 h. Then, hemocytometer count was performed to evaluate cellular viability, using Trypan Blue assay. The normal distribution of data was tested by the Kolmogorov-Smirnov test and the values obtained for cellular viability were statistically analyzed (1-way ANOVA, Tukey's test - P 0.05). Conclusion: The Copaiba oil-based root canal sealer presented promising results in terms of cytotoxicity which indicated its usefulness as a root canal sealer. PMID:25878676

  20. Cytotoxicity evaluation of a copaiba oil-based root canal sealer compared to three commonly used sealers in endodontics

    Directory of Open Access Journals (Sweden)

    Angela Delfina Bittencourt Garrido

    2015-01-01

    Full Text Available Background: The constant development of new root canal sealers has allowed the solution of a large number of clinical cases in endodontics, however, cytotoxicity of such sealers must be tested before their validation as filling materials. The aim of this study was to evaluate the cytotoxic effect of a new Copaiba oil-based root canal sealer (Biosealer [BS] on osteoblast-like Osteo-1 cells. Materials and Methods: The experimental groups were formed according to the culture medium conditioned with the tested sealers, as follows: Control group (CG (culture medium without conditioning; Sealer 26 (S26 - culture medium + S26; Endofill (EF - culture medium + EF; AH Plus (AHP - culture medium + AHP; and BS - culture medium + BS (Copaiba oil-based sealer. The conditioned culture medium was placed in contact with 2 × 10 4 cells cultivated on 60 mm diameter Petri dishes for 24 h. Then, hemocytometer count was performed to evaluate cellular viability, using Trypan Blue assay. The normal distribution of data was tested by the Kolmogorov-Smirnov test and the values obtained for cellular viability were statistically analyzed (1-way ANOVA, Tukey′s test - P 0.05. Conclusion: The Copaiba oil-based root canal sealer presented promising results in terms of cytotoxicity which indicated its usefulness as a root canal sealer.

  1. BIOMODIFICATION OF KENAF USING WHITE ROT FUNGI

    OpenAIRE

    Rasmina Halis,; Hui Rus Tan,; Zaidon Ashaari,; Rozi Mohamed

    2012-01-01

    White rot fungi can be used as a pretreatment of biomass to degrade lignin. It also alters the structure of the lignocellulosic matter, thus increasing its accessibility to enzymes able to convert polysaccharides into simple sugars. This study compares the ability of two species of white rot fungi, Pycnoporous sanguineus and Oxyporus latemarginatus FRIM 31, to degrade lignin in kenaf chips. The white rot fungi were originally isolated from the tropical forest in Malaysia. Kenaf chips were fir...

  2. De novo Transcriptome Assembly of Common Wild Rice (Oryza rufipogon Griff.) and Discovery of Drought-Response Genes in Root Tissue Based on Transcriptomic Data.

    Science.gov (United States)

    Tian, Xin-Jie; Long, Yan; Wang, Jiao; Zhang, Jing-Wen; Wang, Yan-Yan; Li, Wei-Min; Peng, Yu-Fa; Yuan, Qian-Hua; Pei, Xin-Wu

    2015-01-01

    The perennial O. rufipogon (common wild rice), which is considered to be the ancestor of Asian cultivated rice species, contains many useful genetic resources, including drought resistance genes. However, few studies have identified the drought resistance and tissue-specific genes in common wild rice. In this study, transcriptome sequencing libraries were constructed, including drought-treated roots (DR) and control leaves (CL) and roots (CR). Using Illumina sequencing technology, we generated 16.75 million bases of high-quality sequence data for common wild rice and conducted de novo assembly and annotation of genes without prior genome information. These reads were assembled into 119,332 unigenes with an average length of 715 bp. A total of 88,813 distinct sequences (74.42% of unigenes) significantly matched known genes in the NCBI NT database. Differentially expressed gene (DEG) analysis showed that 3617 genes were up-regulated and 4171 genes were down-regulated in the CR library compared with the CL library. Among the DEGs, 535 genes were expressed in roots but not in shoots. A similar comparison between the DR and CR libraries showed that 1393 genes were up-regulated and 315 genes were down-regulated in the DR library compared with the CR library. Finally, 37 genes that were specifically expressed in roots were screened after comparing the DEGs identified in the above-described analyses. This study provides a transcriptome sequence resource for common wild rice plants and establishes a digital gene expression profile of wild rice plants under drought conditions using the assembled transcriptome data as a reference. Several tissue-specific and drought-stress-related candidate genes were identified, representing a fully characterized transcriptome and providing a valuable resource for genetic and genomic studies in plants.

  3. 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

  4. Fusarium basal rot in the Netherlands

    NARCIS (Netherlands)

    Visser, de C.L.M.; Broek, van den R.C.F.M.; Brink, van den L.

    2006-01-01

    Fusarium basal rot of onion, caused by Fusarium oxysporum f.sp. cepae, is a steadily increasing problem in The Netherlands. Financial losses for Dutch farmers confronted with Fusarium basal rot is substantial, due to yield reduction and high storage costs. This paper describes the development and

  5. 7 CFR 29.6039 - Stem rot.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6039 Stem rot. The deterioration of an uncured or frozen stem resulting from bacterial action. Although stem rot results from bacterial action, it is inactive in cured tobacco...

  6. Gene-based SSR markers for common bean (Phaseolus vulgaris L.) derived from root and leaf tissue ESTs: an integration of the BMc series.

    Science.gov (United States)

    Blair, Matthew W; Hurtado, Natalia; Chavarro, Carolina M; Muñoz-Torres, Monica C; Giraldo, Martha C; Pedraza, Fabio; Tomkins, Jeff; Wing, Rod

    2011-03-22

    Sequencing of cDNA libraries for the development of expressed sequence tags (ESTs) as well as for the discovery of simple sequence repeats (SSRs) has been a common method of developing microsatellites or SSR-based markers. In this research, our objective was to further sequence and develop common bean microsatellites from leaf and root cDNA libraries derived from the Andean gene pool accession G19833 and the Mesoamerican gene pool accession DOR364, mapping parents of a commonly used reference map. The root libraries were made from high and low phosphorus treated plants. A total of 3,123 EST sequences from leaf and root cDNA libraries were screened and used for direct simple sequence repeat discovery. From these EST sequences we found 184 microsatellites; the majority containing tri-nucleotide motifs, many of which were GC rich (ACC, AGC and AGG in particular). Di-nucleotide motif microsatellites were about half as common as the tri-nucleotide motif microsatellites but most of these were AGn microsatellites with a moderate number of ATn microsatellites in root ESTs followed by few ACn and no GCn microsatellites. Out of the 184 new SSR loci, 120 new microsatellite markers were developed in the BMc (Bean Microsatellites from cDNAs) series and these were evaluated for their capacity to distinguish bean diversity in a germplasm panel of 18 genotypes. We developed a database with images of the microsatellites and their polymorphism information content (PIC), which averaged 0.310 for polymorphic markers. The present study produced information about microsatellite frequency in root and leaf tissues of two important genotypes for common bean genomics: namely G19833, the Andean genotype selected for whole genome shotgun sequencing from race Peru, and DOR364 a race Mesoamerica subgroup 2 genotype that is a small-red seeded, released variety in Central America. Both race Peru and Mesoamerica subgroup 2 (small red beans) have been understudied in comparison to race Nueva

  7. Seedling root targets

    Science.gov (United States)

    Diane L. Haase

    2011-01-01

    Roots are critical to seedling performance after outplanting. Although root quality is not as quick and simple to measure as shoot quality, target root characteristics should be included in any seedling quality assessment program. This paper provides a brief review of root characteristics most commonly targeted for operational seedling production. These are: root mass...

  8. Spatial Heterogeneity of SOM Concentrations Associated with White-rot Versus Brown-rot Wood Decay.

    Science.gov (United States)

    Bai, Zhen; Ma, Qiang; Dai, Yucheng; Yuan, Haisheng; Ye, Ji; Yu, Wantai

    2017-10-23

    White- and brown-rot fungal decay via distinct pathways imparts characteristic molecular imprints on decomposing wood. However, the effect that a specific wood-rotting type of fungus has on proximal soil organic matter (SOM) accumulation remains unexplored. We investigated the potential influence of white- and brown-rot fungi-decayed Abies nephrolepis logs on forest SOM stocks (i.e., soil total carbon (C) and nitrogen (N)) and the concentrations of amino sugars (microbial necromass) at different depths and horizontal distances from decaying woody debris. The brown-rot fungal wood decay resulted in higher concentrations of soil C and N and a greater increase in microbial necromass (i.e., 1.3- to 1.7-fold greater) than the white-rot fungal wood decay. The white-rot sets were accompanied by significant differences in the proportions of the bacterial residue index (muramic acid%) with soil depth; however, the brown-rot-associated soils showed complementary shifts, primarily in fungal necromass, across horizontal distances. Soil C and N concentrations were significantly correlated with fungal rather than bacterial necromass in the brown-rot systems. Our findings confirmed that the brown-rot fungi-dominated degradation of lignocellulosic residues resulted in a greater SOM buildup than the white-rot fungi-dominated degradation.

  9. Grapevine bunch rots: impacts on wine composition, quality, and potential procedures for the removal of wine faults.

    Science.gov (United States)

    Steel, Christopher C; Blackman, John W; Schmidtke, Leigh M

    2013-06-05

    Bunch rot of grape berries causes economic loss to grape and wine production worldwide. The organisms responsible are largely filamentous fungi, the most common of these being Botrytis cinerea (gray mold); however, there are a range of other fungi responsible for the rotting of grapes such as Aspergillus spp., Penicillium spp., and fungi found in subtropical climates (e.g., Colletotrichum spp. (ripe rot) and Greeneria uvicola (bitter rot)). A further group more commonly associated with diseases of the vegetative tissues of the vine can also infect grape berries (e.g., Botryosphaeriaceae, Phomopsis viticola ). The impact these fungi have on wine quality is poorly understood as are remedial practices in the winery to minimize wine faults. Compounds found in bunch rot affected grapes and wine are typically described as having mushroom, earthy odors and include geosmin, 2-methylisoborneol, 1-octen-3-ol, 2-octen-1-ol, fenchol, and fenchone. This review examines the current state of knowledge about bunch rot of grapes and how this plant disease complex affects wine chemistry. Current wine industry practices to minimize wine faults and gaps in our understanding of how grape bunch rot diseases affect wine production and quality are also identified.

  10. Biology, diagnosis and management of Heterobasidion Root Disease of southern pines

    Science.gov (United States)

    Tyler J. Dreaden; Jason A.  Smith; Michelle M. Cram; David R   Coyle

    2016-01-01

    Heterobasidion root disease (previously called annosum, annosus, or Fomes root disease / root rot) is one of the most economically damaging forest diseases in the Northern Hemisphere. Heterobasidion root disease (HRD) in the southeastern U.S. is caused by the pathogen Heterobasidion irregulare, which infects loblolly, longleaf, pitch, shortleaf, slash, Virginia, and...

  11. Pathogenesis and Treatment of Bovine Foot Rot.

    Science.gov (United States)

    Van Metre, David C

    2017-07-01

    Bovine foot rot (BFR) is an infectious disease of the interdigital skin and subcutaneous tissues of beef and dairy cattle that occurs under a variety of management and environmental settings. The anaerobic, gram-negative bacteria Fusobacterium necrophorum, Porphyromonas levii, and Prevotella intermedia are commonly isolated from lesions. A multitude of host, agent, and environmental factors contribute to the development of BFR. Initiation of systemic antimicrobial therapy early in the course of disease commonly leads to resolution. Delays in treatment may result in extension of infection into deeper bone, synovial structures, or ligamentous structures, and the prognosis for recovery is reduced. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Representing the root water uptake process in the Common Land Model for better simulating the energy and water vapour fluxes in a Central Asian desert ecosystem

    NARCIS (Netherlands)

    Li, Longhui; van der Tol, C.; Chen, Xuelong; Jing, C.; Su, Zhongbo; Luo, G.; Tian, Xin

    2013-01-01

    The ability of roots to take up water depends on both root distribution and root water uptake efficiency. The former can be experimentally measured, while the latter is extremely difficult to determine. Yet a correct representation of root water uptake process in land surface models (LSMs) is

  13. 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. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. RHIZOBACTERIA AS BIOCONTROL AGENTS OF ROOT ROT DISEASE ON SHALLOT

    Directory of Open Access Journals (Sweden)

    Nunik Iriyanti Ramadhan

    2015-01-01

    Full Text Available Shallot is a high-economic value commodity, but so far the supply is still lower than the demand. One of the production problem is “moler” disease of shallot (MDS caused by Fusarium oxysporum f.sp. cepae (FOCe. The aim of this research was to study the potentiality of shallot rhizobacteria (SRB from various soil ordo to inhibit (MDS. This research was held in the Laboratory of Biology and Soil Health and Greenhouse at UNS. This research was carried out by exploring rhizobacteria of shallot planted on Entisols, Andisols, and Vertisols. Rhizobacteria exploration results were tested for their ability to control Fusarium oxysporum f.sp.cepae (FOCe. Inhibitory ability test of SRB to FOCe was carried out in vitro and on shallot in the greenhouse. The green house research used a Completely Randomized Design (CDR with two factors. The first factor was rhizobacteria combination and the second factor was various soil ordo (Andisols, Entisols, and Vertisols. Each treatment was replicated three times. It was obtained three rhizobacteria isolates from Vertisols (B15: 70%, Andisols (B12:45,55%, and Entisols (B10:46,67% being the highest inhibition results to FOCe. The combination of rhizobacteria B12 and B10 provided the lowest intensity.

  15. antagonistic effect of native bacillus isolates against black root rot

    African Journals Online (AJOL)

    ACSS

    A number of fungi and bacteria are known to be very effective .... Round. Convex. Smooth. Wrinkled. Slow. BS024. Irregular and spreading. Flat. Wavy .... Antibiotic effect of bacterial antagonist ..... antagonistic Bacillus and Trichoderma isolates ...

  16. Serpula lacrymans, the dry rot fungus and tolerance towards copper-based wood preservatives

    Science.gov (United States)

    Anne Christine Steenkjaer Hastrup; Frederick Green; Carol Clausen; Bo Jensen

    2005-01-01

    Serpula lacrymans (Wulfen : Fries) Schröter, the dry rot fungus, is considered the most economically important wood decay fungus in temperate regions of the world i.e. northern Europe, Japan and Australia. Previously copper based wood preservatives were the most commonly used preservatives for pressure treatment of wood for building constructions. Because of a...

  17. Foot Rot of Ulluco Caused by Pythium aphanidermatum

    OpenAIRE

    Keisuke, TOMIOKA; Toyozo, SATO; Tateo, NAKANISHI; National Agricultural Research Center for Western Region; National Institute of Agrobiological Sciences; National Agricultural Research Center for Western Region

    2002-01-01

    Severe rot of stem bases caused by Pythium aphanidermatum was found on ulluco (Ullucus tuberosus) grown in Kagawa Prefecture, Japan, in September 1999. The name "foot rot of ulluco" is proposed for this new disease.

  18. Neuro-Genetics of Reward Deficiency Syndrome (RDS) as the Root Cause of “Addiction Transfer”: A New Phenomenon Common after Bariatric Surgery

    Science.gov (United States)

    Blum, Kenneth; Bailey, John; Gonzalez, Anthony M; Oscar-Berman, Marlene; Liu, Yijun; Giordano, John; Braverman, Eric; Gold, Mark

    2012-01-01

    Now after many years of successful bariatric (weight-loss) surgeries directed at the obesity epidemic clinicians are reporting that some patients are replacing compulsive overeating with newly acquired compulsive disorders such as alcoholism, gambling, drugs, and other addictions like compulsive shopping and exercise. This review article explores evidence from psychiatric genetic animal and human studies that link compulsive overeating and other compulsive disorders to explain the phenomenon of addiction transfer. Possibly due to neurochemical similarities, overeating and obesity may act as protective factors reducing drug reward and addictive behaviors. In animal models of addiction withdrawal from sugar induces imbalances in the neurotransmitters, acetylcholine and dopamine, similar to opiate withdrawal. Many human neuroimaging studies have supported the concept of linking food craving to drug craving behavior. Previously our laboratory coined the term Reward Deficiency Syndrome (RDS) for common genetic determinants in predicting addictive disorders and reported that the predictive value for future RDS behaviors in subjects carrying the DRD2 Taq A1 allele was 74%. While poly genes play a role in RDS, we have also inferred that disruptions in dopamine function may predispose certain individuals to addictive behaviors and obesity. It is now known that family history of alcoholism is a significant obesity risk factor. Therefore, we hypothesize here that RDS is the root cause of substituting food addiction for other dependencies and potentially explains this recently described Phenomenon (addiction transfer) common after bariatric surgery. PMID:23483116

  19. Biodegrading effects of some rot fungi on Pinus caribaea wood

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-16

    May 16, 2008 ... species of white-rot fungi; Corioliopsis polyzona and Pleurotus squarrosulus, and two species of brown- rot fungi; Lentinus ... The results indicated that biodegradation by rot fungi differs in intensity according to the fungus ..... wood of coast red wood Sequoia Sempervirens (D. Don). For. Prod. J. 33(5): 15-20 ...

  20. RESISTANCE TO POST-HARVEST MICROBIAL ROT IN YAM ...

    African Journals Online (AJOL)

    ACSS

    for resistance to internal rot, with Olordor and Kplondzo recording the lowest internal microbial rot, suggesting their potential in .... material. Dried maize stocks were then used to cover the pile of tubers. There were four .... effort in breeding for host plant resistance. Also, ... rot in Dioscorea species under all storage methods.

  1. Variation and inheritance of iron reductase activity in the roots of common bean (Phaseolus vulgaris L.) and association with seed iron accumulation QTL.

    Science.gov (United States)

    Blair, Matthew W; Knewtson, Sharon Jb; Astudillo, Carolina; Li, Chee-Ming; Fernandez, Andrea C; Grusak, Michael A

    2010-10-05

    Iron deficiency anemia is a global problem which often affects women and children of developing countries. Strategy I plants, such as common bean (Phaseolus vulgaris L.) take up iron through a process that involves an iron reduction mechanism in their roots; this reduction is required to convert ferric iron to ferrous iron. Root absorbed iron is critical for the iron nutrition of the plant, and for the delivery of iron to the shoot and ultimately the seeds. The objectives of this study were to determine the variability and inheritance for iron reductase activity in a range of genotypes and in a low × high seed iron cross (DOR364 x G19833), to identify quantitative trait loci (QTL) for this trait, and to assess possible associations with seed iron levels. The experiments were carried out with hydroponically grown plants provided different amounts of iron varying between 0 and 20 μM Fe(III)-EDDHA. The parents, DOR364 and G19833, plus 13 other cultivated or wild beans, were found to differ in iron reductase activity. Based on these initial experiments, two growth conditions (iron limited and iron sufficient) were selected as treatments for evaluating the DOR364 × G19833 recombinant inbred lines. A single major QTL was found for iron reductase activity under iron-limited conditions (1 μM Fe) on linkage group b02 and another major QTL was found under iron sufficient conditions (15 μM Fe) on linkage group b11. Associations between the b11 QTL were found with several QTL for seed iron. Genes conditioning iron reductase activity in iron sufficient bean plants appear to be associated with genes contributing to seed iron accumulation. Markers for bean iron reductase (FRO) homologues were found with in silico mapping based on common bean synteny with soybean and Medicago truncatula on b06 and b07; however, neither locus aligned with the QTL for iron reductase activity. In summary, the QTL for iron reductase activity under iron limited conditions may be useful in

  2. Variation and inheritance of iron reductase activity in the roots of common bean (Phaseolus vulgaris L. and association with seed iron accumulation QTL

    Directory of Open Access Journals (Sweden)

    Fernandez Andrea C

    2010-10-01

    Full Text Available Abstract Background Iron deficiency anemia is a global problem which often affects women and children of developing countries. Strategy I plants, such as common bean (Phaseolus vulgaris L. take up iron through a process that involves an iron reduction mechanism in their roots; this reduction is required to convert ferric iron to ferrous iron. Root absorbed iron is critical for the iron nutrition of the plant, and for the delivery of iron to the shoot and ultimately the seeds. The objectives of this study were to determine the variability and inheritance for iron reductase activity in a range of genotypes and in a low × high seed iron cross (DOR364 × G19833, to identify quantitative trait loci (QTL for this trait, and to assess possible associations with seed iron levels. Results The experiments were carried out with hydroponically grown plants provided different amounts of iron varying between 0 and 20 μM Fe(III-EDDHA. The parents, DOR364 and G19833, plus 13 other cultivated or wild beans, were found to differ in iron reductase activity. Based on these initial experiments, two growth conditions (iron limited and iron sufficient were selected as treatments for evaluating the DOR364 × G19833 recombinant inbred lines. A single major QTL was found for iron reductase activity under iron-limited conditions (1 μM Fe on linkage group b02 and another major QTL was found under iron sufficient conditions (15 μM Fe on linkage group b11. Associations between the b11 QTL were found with several QTL for seed iron. Conclusions Genes conditioning iron reductase activity in iron sufficient bean plants appear to be associated with genes contributing to seed iron accumulation. Markers for bean iron reductase (FRO homologues were found with in silico mapping based on common bean synteny with soybean and Medicago truncatula on b06 and b07; however, neither locus aligned with the QTL for iron reductase activity. In summary, the QTL for iron reductase activity

  3. 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

  4. 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 ...

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

    Science.gov (United States)

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

    2014-01-01

    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...

  6. 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.

  7. Associations of planting date, drought stress, and insects with Fusarium ear rot and fumonisin B1 contamination in California maize.

    Science.gov (United States)

    Parsons, M W; Munkvold, G P

    2010-05-01

    Fusarium ear rot, caused by Fusarium verticillioides, is one of the most common diseases of maize, causing yield and quality reductions and contamination of grain by fumonisins and other mycotoxins. Drought stress and various insects have been implicated as factors affecting disease severity. Field studies were conducted to evaluate the interactions and relative influences of drought stress, insect infestation, and planting date upon Fusarium ear rot severity and fumonisin B1 contamination. Three hybrids varying in partial resistance to Fusarium ear rot were sown on three planting dates and subjected to four irrigation regimes to induce differing levels of drought stress. A foliar-spray insecticide treatment was imposed to induce differing levels of insect injury. Populations of thrips (Frankliniella spp.), damage by corn earworm (Helicoverpa zeae), Fusarium ear rot symptoms, and fumonisin B1 levels were assessed. There were significant effects of hybrid, planting date, insecticide treatment, and drought stress on Fusarium ear rot symptoms and fumonisin B1 contamination, and these factors also had significant interacting effects. The most influential factors were hybrid and insecticide treatment, but their effects were influenced by planting date and drought stress. The more resistant hybrids and the insecticide-treated plots consistently had lower Fusarium ear rot severity and fumonisin B1 contamination. Later planting dates typically had higher thrips populations, more Fusarium ear rot, and higher levels of fumonisin B1. Insect activity was significantly correlated with disease severity and fumonisin contamination, and the correlations were strongest for thrips. The results of this study confirm the influence of thrips on Fusarium ear rot severity in California, USA, and also establish a strong association between thrips and fumonisin B1 levels.

  8. Conjoined lumbosacral nerve roots

    International Nuclear Information System (INIS)

    Kyoshima, Kazumitsu; Nishiura, Iwao; Koyama, Tsunemaro

    1986-01-01

    Several kinds of the lumbosacral nerve root anomalies have already been recognized, and the conjoined nerve roots is the most common among them. It does not make symptoms by itself, but if there is a causation of neural entrapment, for example, disc herniation, lateral recessus stenosis, spondylolisthesis, etc., so called ''biradicular syndrome'' should occur. Anomalies of the lumbosacral nerve roots, if not properly recognized, may lead to injury of these nerves during operation of the lumbar spine. Recently, the chance of finding these anomalous roots has been increased more and more with the use of metrizamide myelography and metrizamide CT, because of the improvement of the opacification of nerve roots. We describe the findings of the anomalous roots as revealed by these two methods. They demonstrate two nerve roots running parallel and the asymmetrical wide root sleeve. Under such circumstances, it is important to distinguish the anomalous roots from the normal ventral and dorsal roots. (author)

  9. Paraphoma crown rot of pyrethrum (Tanacetum cinerariifolium)

    NARCIS (Netherlands)

    Moslemi, Azin; Ades, Peter Kevin; Groom, Tim; Crous, Pedro; Nicolas, Marc Edward; Taylor, Paul William James

    2016-01-01

    Pyrethrum (Tanacetum cinerariifolium) is commercially cultivated for the extraction of natural pyrethrin insecticides from the oil glands inside seeds. Yield-decline has caused significant yield losses in Tasmania during the last decade. A new pathogen of pyrethrum causing crown rot and reduced

  10. BIOMODIFICATION OF KENAF USING WHITE ROT FUNGI

    Directory of Open Access Journals (Sweden)

    Rasmina Halis,

    2012-01-01

    Full Text Available White rot fungi can be used as a pretreatment of biomass to degrade lignin. It also alters the structure of the lignocellulosic matter, thus increasing its accessibility to enzymes able to convert polysaccharides into simple sugars. This study compares the ability of two species of white rot fungi, Pycnoporous sanguineus and Oxyporus latemarginatus FRIM 31, to degrade lignin in kenaf chips. The white rot fungi were originally isolated from the tropical forest in Malaysia. Kenaf chips were first inoculated with each fungus separately using corn steep liquor as a fungal growth promoter. The kenaf chips were inoculated with white rot fungus for a period of 1, 2, 4, 8 and 16 weeks, after which they were observed under the scanning electron microscope (SEM. Chemical analyses were conducted following TAPPI Standard Methods and Fourier Transmission Infra Red (FTIR. SEM observations showed evidence of fungal colonization. When calculating weight loss, both P. sanguineus and O. latemarginatus FRIM 31 showed the greatest reduction. Amounts by mass of cellulose, hemicelluloses, extractives, and lignin in the treated kenaf chips all were lowered. The results show that O. latemarginatus FRIM 31 had a greater ability to degrade lignin when compared to P. sanguineus.

  11. Selection of Common Bean Lines, Recombinant Inbred Lines and Commercial Genotypes Tolerant to Low Phosphorus Availability in an Acrisol Soil on the Basis of Root Traits and Grain Yield

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A.; Gomez, L. A.; Morales, A. [Instituto de Suelos, MINAG (Cuba); others, and

    2013-11-15

    Common bean (Phaseolus vulgaris L.) is the most important food legume for human consumption worldwide and especially in Latin America and Africa, but low soil phosphorus (P) availability limits grain production in these areas. For these reason eighty five recombinant inbred lines (RILs) of BAT 477 x DOR 364 and twenty commercial bean genotypes were sown in plots in an Acrisol soil with low P availability to evaluate nine root traits and grain yield. The study was carried out in Pinar del Rio province in Cuba between November 2006 and February 2009. The plots received basal fertilization (N and K) and P fertilization between 15 and 90 kg P{sub 2}O{sub 5} ha{sup -1}. Ten plants were sampled from each plot at R{sub 6} pod fill to evaluate root traits and shoot biomass, and at R{sub 9} physiological maturity to estimate grain yield. The 85 RILs showed great variability for root traits, grain yield and P stress tolerance calculated as relative grain yield. The commercial bean lines also showed large diversity in yield parameters. Principal Component Analysis showed that there were high and significant correlations between root traits (basal root number, primary root depth, adventitious root length and adventitious root number) and grain yield parameters (grain yield at 15 P level and relative grain yields). Adventitious root traits showed the greatest correlation with yield under low P. Promising RILs included 75.1.1, 60.1.1, 38.1.1, 14.1.1 and 38.1.1 and promising commercial bean lines included ICA Pijao, BAT 482, ICA 23, BAT 24 and BAT 832. (author)

  12. CONTROL OF POSTHARVEST TOMATO ROT BY SPORE SUSPENSION AND ANTIFUNGAL METABOLITES OF TRICHODERMA HARZIANUM

    Directory of Open Access Journals (Sweden)

    Momein H. El-Katatny

    2012-06-01

    Full Text Available 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 pathogens albeit at different degrees. Their culture filtrate inhibited pathogen spore germination possibly due to the released extracellular diffusible metabolite(s. Besides, aberrant morphology of conidia was observed with deformation of hyphal tips. Furthermore, the resulting mycelia appeared desiccated with coagulated protoplasm leading to complete collapse of protoplasm in presence of T. harzianum culture filtrate. Application of T. harzianum spores to tomato fruits decreased disease severity significantly with the most profound effect at higher spore concentrations (108 cells per ml. Similarly, culture filtrate of T. harzianum prevented pathogen spore germination on the surface of tomato fruits leading to decreased incidence of rot symptoms at high culture filtrate concentrations. This work provides strong evidence that T. harzianum is a competent antagonist and its spore suspension and culture filtrate can be used efficiently to control postharvest tomato rot.

  13. Distribution of cranberry fruit-rotting fungi in new jersey and evidence for nonspecific host resistance.

    Science.gov (United States)

    Stiles, C M; Oudemans, P V

    1999-03-01

    ABSTRACT A survey was conducted over a 3-year period to determine the frequencies and distributions of fruit-rotting fungi in New Jersey cranberry beds. In the first 2 years of the study, Physalospora vaccinii and Glomerella cingulata were the most prevalent and widespread field-rotting fungi. In the third year, the frequency of G. cingulata declined markedly. Other species such as Coleophoma empetri, Phyllosticta vaccinii, and Phomopsis vaccinii were isolated at high frequencies from a limited number of locations. Storage-rotting fungi including Allantophomopsis cytisporea and A. lycopodina were isolated at low frequencies, but were widely distributed within the growing region. On sound fruit, a somewhat different profile emerged. Fungi such as Phyllosticta elongata, Alternaria spp., and Physalospora vaccinii were commonly isolated. In comparisons among different cranberry cultivars, no differences in the fungal profiles were seen. This was interpreted to indicate that if differences in fruit-rot resistance exist, they are likely to be general forms of resistance rather than fungal species-specific mechanisms.

  14. Soft rot erwiniae: from genes to genomes.

    Science.gov (United States)

    Toth, Ian K; Bell, Kenneth S; Holeva, Maria C; Birch, Paul R J

    2003-01-01

    SUMMARY The soft rot erwiniae, Erwinia carotovora ssp. atroseptica (Eca), E. carotovora ssp. carotovora (Ecc) and E. chrysanthemi (Ech) are major bacterial pathogens of potato and other crops world-wide. We currently understand much about how these bacteria attack plants and protect themselves against plant defences. However, the processes underlying the establishment of infection, differences in host range and their ability to survive when not causing disease, largely remain a mystery. This review will focus on our current knowledge of pathogenesis in these organisms and discuss how modern genomic approaches, including complete genome sequencing of Eca and Ech, may open the door to a new understanding of the potential subtlety and complexity of soft rot erwiniae and their interactions with plants. The soft rot erwiniae are members of the Enterobacteriaceae, along with other plant pathogens such as Erwinia amylovora and human pathogens such as Escherichia coli, Salmonella spp. and Yersinia spp. Although the genus name Erwinia is most often used to describe the group, an alternative genus name Pectobacterium was recently proposed for the soft rot species. Ech mainly affects crops and other plants in tropical and subtropical regions and has a wide host range that includes potato and the important model host African violet (Saintpaulia ionantha). Ecc affects crops and other plants in subtropical and temperate regions and has probably the widest host range, which also includes potato. Eca, on the other hand, has a host range limited almost exclusively to potato in temperate regions only. Disease symptoms: Soft rot erwiniae cause general tissue maceration, termed soft rot disease, through the production of plant cell wall degrading enzymes. Environmental factors such as temperature, low oxygen concentration and free water play an essential role in disease development. On potato, and possibly other plants, disease symptoms may differ, e.g. blackleg disease is associated

  15. Linking fungal communities in roots, rhizosphere, and soil to the health status of Pisum sativum

    DEFF Research Database (Denmark)

    Xu, Lihui; Ravnskov, Sabine; Larsen, John

    2012-01-01

    the three fields identified a number of OTUs that were more abundant in healthy roots. Pathogens such as Fusarium oxysporum were abundant in diseased roots in some fields. Patterns of disease and causal agents of root rot were different among the three fields, which were also reflected in fungal communities...

  16. 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.

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

    Science.gov (United States)

    D'Souza, T M; Boominathan, K; Reddy, C A

    1996-01-01

    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 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. PMID:8837429

  18. Integrated management of foot rot of lentil using biocontrol agents under field condition.

    Science.gov (United States)

    Hannan, M A; Hasan, M M; Hossain, I; Rahman, S M E; Ismail, Alhazmi Mohammed; Oh, Deog-Hwan

    2012-07-01

    The efficacy of cowdung, Bangladesh Institute of Nuclear Agriculture (BINA)-biofertilizer, and Bangladesh Agricultural University (BAU)-biofungicide, alone or in combination, was evaluated for controlling foot rot disease of lentil. The results exhibited that BINA-biofertilizer and BAUbiofungicide (peat soil-based Rhizobium leguminosarum and black gram bran-based Trichoderma harzianum) are compatible and have combined effects in controlling the pathogenic fungi Fusarium oxysporum and Sclerotium rolfsii, which cause the root rot of lentil. Cowdung mixing with soil (at 5 t/ha) during final land preparation and seed coating with BINA-biofertilizer and BAU-biofungicide (at 2.5% of seed weight) before sowing recorded 81.50% field emergence of lentil, which showed up to 19.85% higher field emergence over the control. Post-emergence deaths of plants due to foot rot disease were significantly reduced after combined seed treatment with BINA-biofertilizer and BAU-biofungicide. Among the treatments used, only BAU-biofungicide as the seed treating agent resulted in higher plant stand (84.82%). Use of BINA-biofertilizer and BAU-biofungicide as seed treating biocontrol agents and application of cowdung in the soil as an organic source of nutrient resulted in higher shoot and root lengths, and dry shoot and root weights of lentil. BINA-biofertilizer significantly increased the number of nodules per plant and nodules weight of lentil. Seeds treating with BAUbiofungicide and BINA-biofertilizer and soil amendment with cowdung increased the biomass production of lentil up to 75.56% over the control.

  19. 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.

  20. Study of effective application of 2,4-D on corn in order to control of red root Pig weed and common lambs quarters, by using of 14 C labeled Herbicide Tracer technique

    International Nuclear Information System (INIS)

    Ahari Mostafavi, H.; Fathollahi, H.; Naserian, B.; Rafiee, H.; Matlobi, M.; Bahaee, M.

    2003-01-01

    One of the suitable way to control the perennial weeds in the corn production is the application of selective herbicides. In order to study the best application time of 2,4-D to control red root weed and common lambs quarters an experiments was carried out at the Nuclear Research Center for agriculture and medicine in Karaj (2001-2002). Based on our research study, different growth stages of corn and two weeds were produced under the activity of 0.05-0.12μCi (in each 10 ml of solution), through the ad axial surface. The plants were harvested 48 hours after the treatment and divided into inoculated leaf, plant above and under the inoculated leaf. This study shows that 2-3 leaf stages of corn is the best application time of selective control of red root pig weed and common lambs quarters

  1. Evaluation of host resistance to Botrytis bunch rot in Vitis spp. and its correlation with Botrytis leaf spot

    Science.gov (United States)

    Botrytis cinerea, the causal agent of Botrytis bunch rot and gray mold, is the number one postharvest disease of fresh grapes in the United States. Fungicide applications are used to manage the disease, but fungicide-resistant isolates are common and postharvest losses occur annually. Host resistanc...

  2. Managing heart rot in live trees for wildlife habitat in young-growth forests of coastal Alaska

    Science.gov (United States)

    Paul E. Hennon; Robin L. Mulvey

    2014-01-01

    Stem decays of living trees, known also as heart rots, are essential elements of wildlife habitat, especially for cavity-nesting birds and mammals. Stem decays are common features of old-growth forests of coastal Alaska, but are generally absent in young, managed forests. We offer several strategies for maintaining or restoring fungal stem decay in these managed...

  3. Weevil - red rot associations in eastern white pine

    Science.gov (United States)

    Myron D. Ostrander; Clifford H. Foster

    1957-01-01

    The presence of red rot (Fomes pini) in pruned white pine stands has often been attributed to the act of pruning. This assumption may well be true for heavily stocked stands where thinning has been neglected and pruning scars are slow to heal. The question then arises: How do we account for the red rot often found in vigorous unpruned white pine stands? Evidence...

  4. Fungi associated with base rot disease of aloe vera (Aloe ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Dec 17, 2008 ... full base rot disease after 6 days of inoculation. Key words: Fungi, base rot, Aloe vera. INTRODUCTION. Aloe barbadensis Miller, popularly called Aloe vera is a phanerogame angiosperm which belongs to the family. Liliaceae. The plant is a perennial drought resistant succulent plant (Figure 1). Aloe vera is ...

  5. ( Azadirachta Indica ) Leaf Extracts on the Rot Fungus ( Fusarium ...

    African Journals Online (AJOL)

    The storage lifespan of kola nuts is challenged by the problem of decay of nuts in storage as a result of the attack by the rot fungus (Fusarium spp). The effect of the neem leaf (Azadirachta indica) extracts on the rot fungus was investigated in order to aid extended kola nuts storage. The aqueous and ethanolic leaf extracts of ...

  6. Diagnostic of dry rot in living trees

    International Nuclear Information System (INIS)

    Schaetzler, H.P.

    1978-01-01

    The γ-desorption method has been used in the early diagnosis of dry rot in trees. The attenuation of a 60 keV γ-beam ( 241 Am) has been measured on eleven healthy spruce disks. It is seen that early diagnostic of rotten trees is limited by natural density variation of the wood itself, but for a 95% confidence level that the wood is diseased, a tree must have an average of less than 0.59 g./cm 3 . (Auth/C.F.)

  7. Ectomycorrhizal Communities on the Roots of Two Beech (Fagus sylvatica) Populations from Contrasting Climates Differ in Nitrogen Acquisition in a Common Environment.

    Science.gov (United States)

    Leberecht, Martin; Dannenmann, Michael; Gschwendtner, Silvia; Bilela, Silvija; Meier, Rudolf; Simon, Judy; Rennenberg, Heinz; Schloter, Michael; Polle, Andrea

    2015-09-01

    Beech (Fagus sylvatica), a dominant forest species in Central Europe, competes for nitrogen with soil microbes and suffers from N limitation under dry conditions. We hypothesized that ectomycorrhizal communities and the free-living rhizosphere microbes from beech trees from sites with two contrasting climatic conditions exhibit differences in N acquisition that contribute to differences in host N uptake and are related to differences in host belowground carbon allocation. To test these hypotheses, young trees from the natural regeneration of two genetically similar populations, one from dryer conditions (located in an area with a southwest exposure [SW trees]) and the other from a cooler, moist climate (located in an area with a northeast exposure [NE trees]), were transplanted into a homogeneous substrate in the same environment and labeled with (13)CO2 and (15)NH4 (+). Free-living rhizosphere microbes were characterized by marker genes for the N cycle, but no differences between the rhizospheres of SW or NE trees were found. Lower (15)N enrichment was found in the ectomycorrhizal communities of the NE tree communities than the SW tree communities, whereas no significant differences in (15)N enrichment were observed for nonmycorrhizal root tips of SW and NE trees. Neither the ectomycorrhizal communities nor the nonmycorrhizal root tips originating from NE and SW trees showed differences in (13)C signatures. Because the level of (15)N accumulation in fine roots and the amount transferred to leaves were lower in NE trees than SW trees, our data support the suggestion that the ectomycorrhizal community influences N transfer to its host and demonstrate that the fungal community from the dry condition was more efficient in N acquisition when environmental constraints were relieved. These findings highlight the importance of adapted ectomycorrhizal communities for forest nutrition in a changing climate. Copyright © 2015, American Society for Microbiology. All Rights

  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. 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 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.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.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.

  10. RUNTIME DICTIONARIES FOR ROOT

    CERN Document Server

    Wind, David Kofoed

    2013-01-01

    ROOT is the LHC physicists' common tool for data analysis; almost all data is stored using ROOT's I/O system. This system benefits from a custom description of types (a so-called dictionary) that is optimised for the I/O. Until now, the dictionary cannot be provided at run-time; it needs to be prepared in a separate prerequisite step. This project will move the generation of the dictionary to run-time, making use of ROOT 6's new just-in-time compiler. It allows a more dynamic and natural access to ROOT's I/O features especially for user code.

  11. Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

    Science.gov (United States)

    Rahman, M. M.; Ali, M. E.; 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 isolates E-45 and E-65 significantly inhibited the in vitro growth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genus Bacillus and the isolate E-45 as Lactobacillus sp. The stronger antagonistic activity against Ecc P-138 was found in E-65 in vitro screening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5%) antagonistic effect of E-65 was observed in the Granola and the lowest (32.7%) of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers. PMID:22645446

  12. Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

    Directory of Open Access Journals (Sweden)

    M. M. Rahman

    2012-01-01

    Full Text Available 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 isolates E-45 and E-65 significantly inhibited the in vitro growth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genus Bacillus and the isolate E-45 as Lactobacillus sp. The stronger antagonistic activity against Ecc P-138 was found in E-65 in vitro screening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5% antagonistic effect of E-65 was observed in the Granola and the lowest (32.7% of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

  13. Antibacterial Effect of Potassium Tetraborate Tetrahydrate against Soft Rot Disease Agent Pectobacterium carotovorum in Tomato

    Directory of Open Access Journals (Sweden)

    Firas A. Ahmed

    2017-09-01

    Full Text Available Soft rot caused by Pectobacterium carotovorum is one of most common bacterial diseases occurring in fruits and vegetables worldwide, yet consumer-acceptable options for post-harvest disease management are still insufficient. We evaluated the effect of potassium tetraborate tetrahydrate (B4K2O7.4H2O (PTB on the growth of P. carotovorum using strain BA17 as a representative of high virulence. Complete inhibition of bacterial growth was achieved by treatment with PTB at 100 mM both at pH 9.2 and after adjustment to pH 7.0. Bactericidal activity was quantified and validated by counting fluorescently labeled live and dead bacterial cells using flow cytometry, and reconfirmed using qPCR with high-affinity photoreactive DNA binding dye propidium monoazide (PMA. The results of flow cytometry, qPCR, and culturing confirmed that bacterial cells were killed following exposure to PTB at 100 mM. Bacterial cell membranes were damaged following a 5-min treatment and extrusion of cytoplasmic material from bacterial cells was observed using electronic transmission microscopy. Soft rot incidence on inoculated tomato fruit was significantly reduced by dipping infected fruits in PTB at 100 mM for 5 min and no lesions developed following a 10-min treatment. PTB does not pose a hazard to human health and is an effective alternative to other bactericides and antibiotics for controlling soft rot disease of tomato caused by P. carotovorum.

  14. Energy balance associated with the degradation of lignocellulosic material by white-rot and brown-rot fungi.

    Science.gov (United States)

    Derrien, Delphine; Bédu, Hélène; Buée, Marc; Kohler, Annegret; Goodell, Barry; Gelhaye, Eric

    2017-04-01

    Forest soils cover about 30% of terrestrial area and comprise between 50 and 80% of the global stock of soil organic carbon (SOC). The major precursor for this forest SOC is lignocellulosic material, which is made of polysaccharides and lignin. Lignin has traditionally been considered as a recalcitrant polymer that hinders access to the much more labile structural polysaccharides. This view appears to be partly incorrect from a microbiology perspective yet, as substrate alteration depends on the metabolic potential of decomposers. In forest ecosystems the wood-rotting Basidiomycota fungi have developed two different strategies to attack the structure of lignin and gain access to structural polysaccharides. White-rot fungi degrade all components of plant cell walls, including lignin, using enzymatic systems. Brown-rot fungi do not remove lignin. They generate oxygen-derived free radicals, such as the hydroxyl radical produced by the Fenton reaction, that disrupt the lignin polymer and depolymerize polysaccharides which then diffuse out to where the enzymes are located The objective of this study was to develop a model to investigate whether the lignin relative persistence could be related to the energetic advantage of brown-rot degradative pathway in comparison to white-rot degradative pathway. The model simulates the changes in substrate composition over time, and determines the energy gained from the conversion of the lost substrate into CO2. The energy cost for the production of enzymes involved in substrate alteration is assessed using information derived from genome and secretome analysis. For brown-rot fungus specifically, the energy cost related to the production of OH radicals is also included. The model was run, using data from the literature on populous wood degradation by Trametes versicolor, a white-rot fungus, and Gloeophyllum trabeum, a brown-rot fungus. It demonstrates that the brown-rot fungus (Gloeophyllum trabeum) was more efficient than the white-rot

  15. Production and optimization of ligninolytic enzymes by white rot ...

    African Journals Online (AJOL)

    Production and optimization of ligninolytic enzymes by white rot fungus Schizophyllum ... size and nutritional factors (carbon and nitrogen ratio, mediators and metal ions). ... scale production of these enzymes for diverse industrial applications.

  16. Biodegrading effects of some rot fungi on Pinus caribaea wood ...

    African Journals Online (AJOL)

    morelet) in Ijaiye Forest Reserve, 38 km northwest of Ibadan, Nigeria. The wood samples were inoculated separately with two species of white-rot fungi; Corioliopsis polyzona and Pleurotus squarrosulus, and two species of brownrot fungi; ...

  17. Red rot resistant transgenic sugarcane developed through expression of β-1,3-glucanase gene.

    Directory of Open Access Journals (Sweden)

    Shivani Nayyar

    Full Text Available Sugarcane (Saccharum spp. is a commercially important crop, vulnerable to fungal disease red rot caused by Colletotrichum falcatum Went. The pathogen attacks sucrose accumulating parenchyma cells of cane stalk leading to severe losses in cane yield and sugar recovery. We report development of red rot resistant transgenic sugarcane through expression of β-1,3-glucanase gene from Trichoderma spp. The transgene integration and its expression were confirmed by quantitative reverse transcription-PCR in first clonal generation raised from T0 plants revealing up to 4.4-fold higher expression, in comparison to non-transgenic sugarcane. Bioassay of transgenic plants with two virulent C. falcatum pathotypes, Cf 08 and Cf 09 causing red rot disease demonstrated that some plants were resistant to Cf 08 and moderately resistant to Cf 09. The electron micrographs of sucrose storing stalk parenchyma cells from these plants displayed characteristic sucrose-filled cells inhibiting Cf 08 hyphae and lysis of Cf 09 hyphae; in contrast, the cells of susceptible plants were sucrose depleted and prone to both the pathotypes. The transgene expression was up-regulated (up to 2.0-fold in leaves and 5.0-fold in roots after infection, as compared to before infection in resistant plants. The transgene was successfully transmitted to second clonal generation raised from resistant transgenic plants. β-1,3-glucanase protein structural model revealed that active sites Glutamate 628 and Aspartate 569 of the catalytic domain acted as proton donor and nucleophile having role in cleaving β-1,3-glycosidic bonds and pathogen hyphal lysis.

  18. 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...

  19. DEGRADATION OF TEXTILE DYES BY WHITE ROT BASIDIOMYCETES

    OpenAIRE

    B.P. PARMAR, P.N. MERVANA B.R.M. VYAS*

    2014-01-01

    ABSTRACT: Dyes released by the textile industries pose a threat to environmental quality. Ligninolytic white-rot basidiomycetes can effectively degrade colored effluents and conventional dyes. White-rot fungi produce various isoforms of extracellular oxidases including laccase, Mn peroxidase and lignin peroxidase (LiP), which are involved in the degradation of lignin in their natural lignocellulosic substrates.  The textile industry, by far the most avid user of synthetic dyes, is in need...

  20. Streptosporangium sonchi sp. nov. and Streptosporangium kronopolitis sp. nov., two novel actinobacteria isolated from a root of common sowthistle (Sonchus oleraceus L.) and a millipede (Kronopolites svenhedind Verhoeff).

    Science.gov (United States)

    Ma, Zhaoxu; Liu, Hui; Liu, Chongxi; He, Hairong; Zhao, Junwei; Wang, Xin; Li, Jiansong; Wang, Xiangjing; Xiang, Wensheng

    2015-06-01

    Two novel actinobacteria, designated strains NEAU-QS7(T) and NEAU-ML10(T), were isolated from a root of Sonchus oleraceus L. and a Kronopolites svenhedind Verhoeff specimen, respectively, collected from Wuchang, Heilongjiang Province, China. A polyphasic study was carried out to establish the taxonomic positions of these strains. The two strains were observed to form abundant aerial hyphae that differentiated into spherical spore vesicles. The phylogenetic analysis based on the 16S rRNA gene sequences of strains NEAU-QS7(T) and NEAU-ML10(T) showed that the two novel isolates exhibited 99.7 % 16S rRNA gene sequence similarity with each other and that they are most closely related to Streptosporangium shengliense NEAU-GH7(T) (99.1, 99.0 %) and Streptosporangium longisporum DSM 43180(T) (99.1, 99.0 %). However, the DNA-DNA hybridization value between strains NEAU-QS7(T) and NEAU-ML10(T) was 46.5 %, and the values between the two strains and their closest phylogenetic relatives were also below 70 %. With reference to phenotypic characteristics, phylogenetic data and DNA-DNA hybridization results, the two strains can be distinguished from each other and their closest phylogenetic relatives. Thus, strains NEAU-QS7(T) and NEAU-ML10(T) represent two novel species of the genus Streptosporangium, for which the names Streptosporangium sonchi sp. nov. and Streptosporangium kronopolitis sp. nov. are proposed. The type strains are NEAU-QS7(T) (=CGMCC 4.7142(T) =DSM 46717(T)) and NEAU-ML10(T) (=CGMCC 4.7153(T) =DSM 46720(T)), respectively.

  1. Comparative studies on thermochemical characterization of corn stover pretreated by white-rot and brown-rot fungi.

    Science.gov (United States)

    Zeng, Yelin; Yang, Xuewei; Yu, Hongbo; Zhang, Xiaoyu; Ma, Fuying

    2011-09-28

    The effects of white-rot and brown-rot fungal pretreatment on the chemical composition and thermochemical conversion of corn stover were investigated. Fungus-pretreated corn stover was analyzed by Fourier transform infrared spectroscopy and X-ray diffraction analysis to characterize the changes in chemical composition. Differences in thermochemical conversion of corn stover after fungal pretreatment were investigated using thermogravimetric and pyrolysis analysis. The results indicated that the white-rot fungus Irpex lacteus CD2 has great lignin-degrading ability, whereas the brown-rot fungus Fomitopsis sp. IMER2 preferentially degrades the amorphous regions of the cellulose. The biopretreatment favors thermal decomposition of corn stover. The weight loss of IMER2-treated acid detergent fiber became greater, and the oil yield increased from 32.7 to 50.8%. After CD2 biopretreatment, 58% weight loss of acid detergent lignin was achieved and the oil yield increased from 16.8 to 26.8%.

  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. Response of cultivars of malanga (Xanthosoma sagittifolium (L. Schott to dry rot

    Directory of Open Access Journals (Sweden)

    Ernesto Espinosa Cuéllar

    2017-01-01

    Full Text Available Malanga (Xanthosoma sagittifolium (L. Schott is an important food crop for over 400 million people in the tropics and subtropics. In order to determine the response of different varieties of malanga Xanthosoma to dry rot, a series of experiments were conducted in the period between 2012 and 2014. The experiments were performed on loamy Soil at the National Research Institute in Tropical Crops and Roots (INIVIT. We determined the incidence and severity of damage, yields and percent of losses at harvest. The lowest values of incidence and the highest total return was achieved in clons ‘INIVIT MX-95-2’, ‘INIVIT MX-95-1’ and ‘INIVIT MX-2007’. Clones of malanga Xanthosoma belonging to the group purple, showed lower incidence that of white and yellow groups. These results will allow selecting cultivars of malanga with greater resistance to the dry rot and with this to diminish the losses in the harvest.

  4. 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....

  5. An USH2A founder mutation is the major cause of Usher syndrome type 2 in Canadians of French origin and confirms common roots of Quebecois and Acadians

    Science.gov (United States)

    Ebermann, Inga; Koenekoop, Robert K; Lopez, Irma; Bou-Khzam, Lara; Pigeon, Renée; Bolz, Hanno J

    2009-01-01

    Congenital hearing loss affects approximately one child in 1000. About 10% of the deaf population have Usher syndrome (USH). In USH, hearing loss is complicated by retinal degeneration with onset in the first (USH1) or second (USH2) decade. In most populations, diagnostic testing is hampered by a multitude of mutations in nine genes. We have recently shown that in French Canadians from Quebec, USH1 largely results from a single USH1C founder mutation, c.216G>A (‘Acadian allele'). The genetic basis of USH2 in Canadians of French descent, however, has remained elusive. Here, we have investigated nine USH2 families from Quebec and New Brunswick (the former Acadia) by haplotype analyses of the USH2A locus and sequencing of the three known USH2 genes. Seven USH2A mutations were identified in eight patients. One of them, c.4338_4339delCT, accounts for 10 out of 18 disease alleles (55.6%). This mutation has previously been reported in an Acadian USH2 family, and it was found in homozygous state in the three Acadians of our sample. As in the case of c.216G>A (USH1C), a common haplotype is associated with c.4338_4339delCT. With a limited number of molecular tests, it will now be possible in these populations to estimate whether children with congenital hearing impairment of different degrees will develop retinal disease – with important clinical and therapeutic implications. USH2 is the second example that reveals a significant genetic overlap between Quebecois and Acadians: in contrast to current understanding, other genetic disorders present in both populations are likely based on common founder mutations as well. PMID:18665195

  6. An USH2A founder mutation is the major cause of Usher syndrome type 2 in Canadians of French origin and confirms common roots of Quebecois and Acadians.

    Science.gov (United States)

    Ebermann, Inga; Koenekoop, Robert K; Lopez, Irma; Bou-Khzam, Lara; Pigeon, Renée; Bolz, Hanno J

    2009-01-01

    Congenital hearing loss affects approximately one child in 1000. About 10% of the deaf population have Usher syndrome (USH). In USH, hearing loss is complicated by retinal degeneration with onset in the first (USH1) or second (USH2) decade. In most populations, diagnostic testing is hampered by a multitude of mutations in nine genes. We have recently shown that in French Canadians from Quebec, USH1 largely results from a single USH1C founder mutation, c.216G>A ('Acadian allele'). The genetic basis of USH2 in Canadians of French descent, however, has remained elusive. Here, we have investigated nine USH2 families from Quebec and New Brunswick (the former Acadia) by haplotype analyses of the USH2A locus and sequencing of the three known USH2 genes. Seven USH2A mutations were identified in eight patients. One of them, c.4338_4339delCT, accounts for 10 out of 18 disease alleles (55.6%). This mutation has previously been reported in an Acadian USH2 family, and it was found in homozygous state in the three Acadians of our sample. As in the case of c.216G>A (USH1C), a common haplotype is associated with c.4338_4339delCT. With a limited number of molecular tests, it will now be possible in these populations to estimate whether children with congenital hearing impairment of different degrees will develop retinal disease - with important clinical and therapeutic implications. USH2 is the second example that reveals a significant genetic overlap between Quebecois and Acadians: in contrast to current understanding, other genetic disorders present in both populations are likely based on common founder mutations as well.

  7. High-throughput sequencing of black pepper root transcriptome

    Science.gov (United States)

    2012-01-01

    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. PMID:22984782

  8. 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.

  9. Evaluation of antimicrobial effect of azadirachtin plant extract (Soluneem ™ on commonly found root canal pathogenic microorganisms (viz. Enterococcus faecalis in primary teeth: A microbiological study

    Directory of Open Access Journals (Sweden)

    Shanal Shah

    2016-01-01

    Full Text Available Aim: The aim of this study is to evaluate the antimicrobial activity of Soluneem ™ when used as an irrigating solution along with other commonly used irrigating solution sodium hypochlorite (NaOCl against Enterococcus faecalis. Materials and Methods: Microorganism used in this study was E. faecalis (Microbial Type Culture Collection 439. Test substance used was Soluneem ™, which was obtained from Vittal Mallya Scientific Research Foundation (VMSRF, Bengaluru. This study was conducted in a microbiology laboratory (Biocare Research India Pvt., Ltd. Laboratory, Ahmedabad, Gujarat to evaluate the antimicrobial effect of Soluneem ™ (Azadirachtin on E. faecalis. Antimicrobial activity testing was performed using the macrobroth dilution method according to the Clinical Laboratory Standards Institute guidelines. All determinations were performed thrice. Results: Minimum bactericidal concentration (MBC was seen as 2.6% for Soluneem ™ while the same was seen at 0.1% for NaOCl. Independent sample t-test was carried out to compare the MBC of Soluneem ™ and NaOCl, which showed that there was no statistically significant difference between them, i.e., 2.6% Soluneem ™ was as effective as 0.1% NaOCl. Conclusion: Soluneem ™ showed antimicrobial activity against E. faecalis at various concentrations. It was also found that the efficacy of Soluneem ™ at 2.6% concentration and above was relatively similar to that of gold standard irrigating solution (NaOCl on inhibition of E. faecalis.

  10. Evaluation of antimicrobial effect of azadirachtin plant extract (Soluneem (™)) on commonly found root canal pathogenic microorganisms (viz. Enterococcus faecalis) in primary teeth: A microbiological study.

    Science.gov (United States)

    Shah, Shanal; Venkataraghavan, Karthik; Choudhary, Prashant; Mohammad, Shameer; Trivedi, Krishna; Shah, Shalin G

    2016-01-01

    The aim of this study is to evaluate the antimicrobial activity of Soluneem ™ when used as an irrigating solution along with other commonly used irrigating solution sodium hypochlorite (NaOCl) against Enterococcus faecalis. Microorganism used in this study was E. faecalis (Microbial Type Culture Collection 439). Test substance used was Soluneem ™, which was obtained from Vittal Mallya Scientific Research Foundation (VMSRF), Bengaluru. This study was conducted in a microbiology laboratory (Biocare Research India Pvt., Ltd. Laboratory, Ahmedabad, Gujarat) to evaluate the antimicrobial effect of Soluneem ™ (Azadirachtin) on E. faecalis. Antimicrobial activity testing was performed using the macrobroth dilution method according to the Clinical Laboratory Standards Institute guidelines. All determinations were performed thrice. Minimum bactericidal concentration (MBC) was seen as 2.6% for Soluneem ™ while the same was seen at 0.1% for NaOCl. Independent sample t-test was carried out to compare the MBC of Soluneem ™ and NaOCl, which showed that there was no statistically significant difference between them, i.e., 2.6% Soluneem ™ was as effective as 0.1% NaOCl. Soluneem ™ showed antimicrobial activity against E. faecalis at various concentrations. It was also found that the efficacy of Soluneem ™ at 2.6% concentration and above was relatively similar to that of gold standard irrigating solution (NaOCl) on inhibition of E. faecalis.

  11. Use of an exchange method to estimate the association and dissociation rate constants of cadmium complexes formed with low-molecular-weight organic acids commonly exuded by plant roots.

    Science.gov (United States)

    Schneider, André; Nguyen, Christophe

    2011-01-01

    Organic acids released from plant roots can form complexes with cadmium (Cd) in the soil solution and influence metal bioavailability not only due to the nature and concentration of the complexes but also due to their lability. The lability of a complex influences its ability to buffer changes in the concentration of free ions (Cd); it depends on the association (, m mol s) and dissociation (, s) rate constants. A resin exchange method was used to estimate and (m mol s), which is the conditional estimate of depending on the calcium (Ca) concentration in solution. The constants were estimated for oxalate, citrate, and malate, three low-molecular-weight organic acids commonly exuded by plant roots and expected to strongly influence Cd uptake by plants. For all three organic acids, the and estimates were around 2.5 10 m mol s and 1.3 × 10 s, respectively. Based on the literature, these values indicate that the Cd- low-molecular-weight organic acids complexes formed between Cd and low-molecular-weight organic acids may be less labile than complexes formed with soil soluble organic matter but more labile than those formed with aminopolycarboxylic chelates. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Reaction of Cauliflower Genotypes to Black Rot of Crucifers

    Directory of Open Access Journals (Sweden)

    Lincon Rafael da Silva

    2015-06-01

    Full Text Available This study aimed to evaluate six cauliflower genotypes regarding their resistance to black rot and their production performance. To do so, it was conducted two field experiments in Ipameri, Goiás, Brazil, in 2012 and 2013. It was used a randomized block design, with four replications (total of 24 plots. Each plot consisted of three planting lines 2.5 m long (six plants/line, spaced 1.0 m apart, for a total area of 7.5 m². Evaluations of black rot severity were performed at 45 days after transplanting, this is, 75 days after sowing (DAS, and yield evaluations at 90 to 105 DAS. The Verona 184 genotype was the most resistant to black rot, showing 1.87 and 2.25% of leaf area covered by black rot symptom (LACBRS in 2012 and 2013. However, it was not among the most productive materials. The yield of the genotypes varied between 15.14 and 25.83 t/ha in both years, Lisvera F1 (21.78 and 24.60 t/ha and Cindy (19.95 and 23.56 t/ha being the most productive. However, Lisvera F1 showed 6.37 and 9.37% of LACBRS and Cindy showed 14.25 and 14.87% of LACBRS in 2012 and 2013, being both considered as tolerant to black rot.

  13. Aggressive root pathogen Phellinus noxius and implications for western Pacific Islands

    Science.gov (United States)

    Sara M. Ashiglar; Phil G. Cannon; Ned B. Klopfenstein

    2015-01-01

    Phellinus noxius is an aggressive root rot pathogen affecting tropical and subtropical forests. Causing much damage in tropical Asia, Africa, Taiwan, Japan and the Pacific Islands, its wide host range encompasses more than 200 plant species representing 59 families (Ann et al. 2002). It can devastate agricultural plantations of tea, rubber, cocoa, avocados,...

  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. First report of Fusarium proliferatum causing dry rot in Michigan commercial potato (Solanum tuberosum) production

    Science.gov (United States)

    Fusarium dry rot of potato is a postharvest disease caused by several Fusarium spp. and is of worldwide importance. Thirteen Fusarium spp. have been implicated in fungal dry rots of potatoes worldwide. Among them, 11 species have been reported causing potato dry rot of seed tubers in the northern Un...

  16. Fusarium spp. causing dry rot of seed potato tubers in Michigan and their sensitivity to fungicides

    Science.gov (United States)

    Fusarium dry rot of potato (Solanum tuberosum L.) is a postharvest disease that can be caused by several Fusarium spp. A survey was conducted to establish the composition of Fusarium species causing dry rot of seed tubers in Michigan. A total of 370 dry rot symptomatic tubers were collected in 2009 ...

  17. 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...

  18. Root patterning

    NARCIS (Netherlands)

    Scheres, Ben; Laskowski, Marta

    2016-01-01

    The mechanisms that pattern lateral root primordial are essential for the elaboration of root system architecture, a trait of key importance for future crop breeding. But which are most important: periodic or local cues? In this issue of Journal of Experimental Botany (pages 1411-1420), Kircher

  19. On the trail of the common roots

    Directory of Open Access Journals (Sweden)

    Francesca Puddu

    2009-01-01

    Full Text Available Discussione di un'esperienza didattica svolta nell’ambito di un progetto di TwinningQuest, che prevede l'uso di WebQuest in progetti di gemellaggio tra scuole di differenti nazioni per supportare, coordinare e integrare il lavoro delle classi coinvolte.

  20. Salmonella enterica suppresses Pectobacterium carotovorum subsp. carotovorum population and soft rot progression by acidifying the microaerophilic environment.

    Science.gov (United States)

    Kwan, Grace; Charkowski, Amy O; Barak, Jeri D

    2013-02-12

    and human hosts. Their populations are higher on plants cocolonized with the common bacterial soft rot pathogen Pectobacterium carotovorum subsp. carotovorum, turning edible plants into a risk factor for human disease. We inoculated leaves with P. carotovorum subsp. carotovorum and S. enterica or E. coli O157:H7 to study the interactions between these bacteria. While P. carotovorum subsp. carotovorum enhanced the growth of both S. enterica and E. coli O157:H7, these human pathogens affected P. carotovorum subsp. carotovorum fundamentally differently. S. enterica reduced P. carotovorum subsp. carotovorum growth and acidified the environment, leading to less soft rot on leaves; E. coli O157:H7 had no such effects. As soft rot signals a food safety risk, the reduction of soft rot symptoms in the presence of S. enterica may lead consumers to eat healthy-looking but S. enterica-contaminated produce.

  1. Bacterial Infection Potato Tuber Soft Rot Disease Detection Based on Electronic Nose

    Directory of Open Access Journals (Sweden)

    Chang Zhiyong

    2017-11-01

    Full Text Available Soft rot is a severe bacterial disease of potatoes, and soft rot infection can cause significant economic losses during the storage period of potatoes. In this study, potato soft rot was selected as the research object, and a type of potato tuber soft rot disease early detection method based on the electronic nose technology was proposed. An optimized bionic electronic nose gas chamber and a scientific and reasonable sampling device were designed to detect a change in volatile substances of the infected soft rot disease of potato tuber. The infection of soft rot disease in potato tuber samples was detected and identified by using the RBF NN algorithm and SVM algorithm. The results revealed that the proposed bionic electronic nose system can be utilized for early detection of potato tuber soft rot disease. Through comparison and analysis, the recognition rate using the SVM algorithm reached up to 89.7%, and the results were superior to the RBF NN algorithm.

  2. 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...

  3. Inflorescence rot disease of date palm caused by Fusarium ...

    African Journals Online (AJOL)

    Date palm is one of the important income sources for many farmers in different parts of several countries, including Iraq, Iran, Saudi Arabia, North Africa etc. Inflorescence rot is a serious disease of date palm which limits its yield. The identification of the causal organism is a key step to tackling this disease, and such studies ...

  4. Huanglongbing increases Diplodia Stem End Rot in Citrus sinensis

    Science.gov (United States)

    Huanglongbing (HLB), one of the most devastating diseases of citrus is caused by the a-Proteobacteria Candidatus Liberibacter. Diplodia natalensis Pole-Evans is a fungal pathogen which has been known to cause a postharvest stem-end rot of citrus, the pathogen infects citrus fruit under the calyx, an...

  5. 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...

  6. Botanicals to Control Soft Rot Bacteria of Potato

    Directory of Open Access Journals (Sweden)

    M. M. Rahman

    2012-01-01

    Full Text Available 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 vitro and storage conditions. Previously, Ecc P-138 was identified as the most aggressive soft rot bacterium in Bangladeshi potatoes. Of the 11 different plant extracts, only extracts from dried jute leaves and cheerota significantly inhibited growth of Ecc P-138 in vitro. Finally, both plant extracts were tested to control the soft rot disease of potato tuber under storage conditions. In a 22-week storage condition, the treated potatoes were significantly more protected against the soft rot infection than those of untreated samples in terms of infection rate and weight loss. The jute leaf extracts showed more pronounced inhibitory effects on Ecc-138 growth both in in vitro and storage experiments.

  7. Fungi associated with base rot disease of aloe vera ( Aloe ...

    African Journals Online (AJOL)

    Fungi associated with base rot disease of Aloe vera (syn. Aloe barbadensis) were investigated in Niger Delta Area of Nigeria. Fungi and their percentage frequency were Aspergillus verocosa 28.03%, Fusarium oxysporium 24.24%, Plectosphaerella cucumerina 16.67%, Mammeria ehinobotryoides 15.91% and Torula ...

  8. Management of Potato Soft Rot by Gamma Irradiation

    International Nuclear Information System (INIS)

    Abd El-Ghany, H.; Moussa, Z.; Abd El-Rahman, A.F.; Salem, E.A.

    2017-01-01

    This investigation aims to apply a safe practice to minimize potato losses due to soft rot disease of tubers kept under ambient temperature. In this regard, gamma irradiation was used to extend keeping quality through its effect on soft rot bacteria. Eight bacterial isolates were recovered on Logan’s medium from kitchen kept tubers with symptoms of soft rot disease. Five isolates were found pathogenic and tentatively identified as Pectobacterium atrosepticum and Pectobacterium carotovorum sub sp. brasiliense on the basis of the usual bacteriological methods. A molecular method using 16SrDNA sequence analysis for verification of the identity of two isolates was made. The two bacterial isolates, Pectobacterium atrosepticum and Pectobacterium carotovorum sub sp. brasiliense, were irradiated by different doses of gamma rays. Complete inhibition occurred at doses 2.5 and 2.0 KGy for high densities (Approximately 4.0x10"9 CFU/ml) of P. atrosepticum and P. carotovorum sub sp. brasiliense, respectively. The D10 value of gamma irradiation was 0.24 KGy for P. atrosepticum and 0.20 KGy for P. carotovorum subsp. brasiliense. Irradiation of artificially infected tubers with soft rot bacteria using the two mentioned D10 doses for the two bacterial species increased the shelf life of tubers kept under ambient temperature. The internal chemical quality of tubers was shown to be improved by keeping the tubers under ambient temperature after irradiation by the two D10 doses 0.24 and 0.20 KGy

  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...... processes provoked by trauma and orthodontic pressure. Inflammatory reactions are followed by resorptive processes in the periroot sheet and along the root surface. Evaluation of the Hypothesis: Different morphologies in the dentition are signs of abnormal epithelium or an abnormal mesodermal layer. It has...

  10. Rice-Infecting Pseudomonas Genomes Are Highly Accessorized and Harbor Multiple Putative Virulence Mechanisms to Cause Sheath Brown Rot

    Science.gov (United States)

    Quibod, Ian Lorenzo; Grande, Genelou; Oreiro, Eula Gems; Borja, Frances Nikki; Dossa, Gerbert Sylvestre; Mauleon, Ramil; Cruz, Casiana Vera; Oliva, Ricardo

    2015-01-01

    Sheath rot complex and seed discoloration in rice involve a number of pathogenic bacteria that cannot be associated with distinctive symptoms. These pathogens can easily travel on asymptomatic seeds and therefore represent a threat to rice cropping systems. Among the rice-infecting Pseudomonas, P. fuscovaginae has been associated with sheath brown rot disease in several rice growing areas around the world. The appearance of a similar Pseudomonas population, which here we named P. fuscovaginae-like, represents a perfect opportunity to understand common genomic features that can explain the infection mechanism in rice. We showed that the novel population is indeed closely related to P. fuscovaginae. A comparative genomics approach on eight rice-infecting Pseudomonas revealed heterogeneous genomes and a high number of strain-specific genes. The genomes of P. fuscovaginae-like harbor four secretion systems (Type I, II, III, and VI) and other important pathogenicity machinery that could probably facilitate rice colonization. We identified 123 core secreted proteins, most of which have strong signatures of positive selection suggesting functional adaptation. Transcript accumulation of putative pathogenicity-related genes during rice colonization revealed a concerted virulence mechanism. The study suggests that rice-infecting Pseudomonas causing sheath brown rot are intrinsically diverse and maintain a variable set of metabolic capabilities as a potential strategy to occupy a range of environments. PMID:26422147

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

    Directory of Open Access Journals (Sweden)

    Ivana Puglisi

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

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

    Science.gov (United States)

    Puglisi, Ivana; De Patrizio, Alessandro; Schena, Leonardo; Jung, Thomas; Evoli, Maria; Pane, Antonella; Van Hoa, Nguyen; Van Tri, Mai; Wright, Sandra; Ramstedt, Mauritz; Olsson, Christer; Faedda, Roberto; Magnano di San Lio, Gaetano; Cacciola, Santa Olga

    2017-01-01

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

  13. Removal of root filling materials.

    LENUS (Irish Health Repository)

    Duncan, H.F. Chong, B.S.

    2011-05-01

    Safe, successful and effective removal of root filling materials is an integral component of non-surgical root canal re-treatment. Access to the root canal system must be achieved in order to negotiate to the canal terminus so that deficiencies in the original treatment can be rectified. Since a range of materials have been advocated for filling root canals, different techniques are required for their removal. The management of commonly encountered root filling materials during non-surgical re-treatment, including the clinical procedures necessary for removal and the associated risks, are reviewed. As gutta-percha is the most widely used and accepted root filling material, there is a greater emphasis on its removal in this review.

  14. Ethylene: a regulator of root architectural responses to soil phosphorus availability

    NARCIS (Netherlands)

    Borch, K.; Bouma, T.J.; Lynch, J.P.; Brown, K.M.

    1999-01-01

    The involvement of ethylene in root architectural responses to phosphorus availability was investigated in common bean (Phaseolus vulgaris L,) plants grown with sufficient and deficient phosphorus. Although phosphorus deficiency reduced root mass and lateral root number, main root length was

  15. Biological Control of White Rot in Garlic Using Burkholderia pyrrocinia CAB08106-4

    Directory of Open Access Journals (Sweden)

    Kwang Seop Han

    2013-03-01

    Full Text Available White rot caused by Sclerotium cepivorum was reported to be severe soil-born disease on garlic. Disease progress of white rot of garlic (Allium sativum L. was investigated during the growing season of 2009 to 2011 at Taean and Seosan areas. The white rot disease on bulb began to occur from late April and peaked in late May. The antifungal bacteria, Burkholderia pyrrocinia CAB08106-4 was tested in field bioassay for suppression of white rot disease. As a result of the nucleotide sequence of the gene 16S rRNA, CAB008106-4 strain used in this study has been identified as B. pyrrocinia. B. pyrrocinia CAB080106-4 isolate suppressed the white rot with 69.6% control efficacy in field test. These results suggested that B. pyrrocinia CAB08106-4 isolate could be an effective biological control agent against white rot of garlic.

  16. Removal of phenanthrene in contaminated soil by combination of alfalfa, white-rot fungus, and earthworms.

    Science.gov (United States)

    Deng, Shuguang; Zeng, Defang

    2017-03-01

    The aim of this study was to investigate the removal of phenanthrene by combination of alfalfa, white-rot fungus, and earthworms in soil. A 60-day experiment was conducted. Inoculation with earthworms and/or white-rot fungus increased alfalfa biomass and phenanthrene accumulation in alfalfa. However, inoculations of alfalfa and white-rot fungus can significantly decrease the accumulation of phenanthrene in earthworms. The removal rates for phenanthrene in soil were 33, 48, 66, 74, 85, and 93% under treatments control, only earthworms, only alfalfa, earthworms + alfalfa, alfalfa + white-rot fungus, and alfalfa + earthworms + white-rot fungus, respectively. The present study demonstrated that the combination of alfalfa, earthworms, and white-rot fungus is an effective way to remove phenanthrene in the soil. The removal is mainly via stimulating both microbial development and soil enzyme activity.

  17. Following basal stem rot in young oil palm plantings.

    Science.gov (United States)

    Panchal, G; Bridge, P D

    2005-01-01

    The PCR primer GanET has previously been shown to be suitable for the specific amplification of DNA from Ganoderma boninense. A DNA extraction and PCR method has been developed that allows for the amplification of the G. boninense DNA from environmental samples of oil palm tissue. The GanET primer reaction was used in conjunction with a palm-sampling programme to investigate the possible infection of young palms through cut frond base surfaces. Ganoderma DNA was detected in frond base material at a greater frequency than would be expected by comparison with current infection levels. Comparisons are made between the height of the frond base infected, the number of frond bases infected, and subsequent development of basal stem rot. The preliminary results suggest that the development of basal stem rot may be more likely to occur when young lower frond bases are infected.

  18. Association of Pectolytic Fluorescent PSeudomonas with Postharvest Rots of Onion

    Directory of Open Access Journals (Sweden)

    H.H. El-Hendawy

    2004-12-01

    Full Text Available Five isolates of pectolytic fluorescent pseudomonads were obtained from a rotted onion bulb and identified as Pseudomonas marginalis. At both 4 and 25oC, all isolates caused soft rot to detached plant parts of onion and to carrot, celery, cucumber, pepper, spinach, tomato and turnip (but not garlic. They did not however cause any symptoms in living plants of these same species. These results suggest that the onion isolates are a postharvest pathogen which is not destructive in the field but becomes a threat to fresh vegetables stored at low-temperature. Analysis of cellulosolytic and pectic enzymes revealed that pectic lyases, but not polygalacturonases, pectin methyl esterases and cellulases were produced in culture by each isolate.

  19. 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.

  20. Fungal hydroquinones contribute to brown rot of wood

    Science.gov (United States)

    Melissa R. Suzuki; Christopher G. Hunt; Carl J. Houtman; Zachary D. Dalebroux; Kenneth E. Hammel

    2006-01-01

    The fungi that cause brown rot of wood initiate lignocellulose breakdown with an extracellular Fenton system in which Fe2+ and H2O2 react to produce hydroxyl radicals (•OH), which then oxidize and cleave the wood holocellulose. One such fungus, Gloeophyllum trabeum, drives Fenton chemistry on defined media by reducing Fe3+ and O2 with two extracellular hydroquinones,...

  1. Cellulose Degradation by Cellulose-Clearing and Non-Cellulose-Clearing Brown-Rot Fungi

    OpenAIRE

    Highley, Terry L.

    1980-01-01

    Cellulose degradation by four cellulose-clearing brown-rot fungi in the Coniophoraceae—Coniophora prasinoides, C. puteana, Leucogyrophana arizonica, and L. olivascens—is compared with that of a non-cellulose-clearing brown-rot fungus, Poria placenta. The cellulose- and the non-cellulose-clearing brown-rot fungi apparently employ similar mechanisms to depolymerize cellulose; most likely a nonenzymatic mechanism is involved.

  2. Induction of somaclonal variation and mutations in sugarcane calli for selecting mutants with resistance to red-rot and tolerance to water-logged conditions

    International Nuclear Information System (INIS)

    Shaikh, M.A.Q.; Begum, S.; Samad, M.A.; Shmsuzzaman, K.M.

    1997-01-01

    Immature leaves of cv. 'Isd-16' of sugarcane were cultured on modified MS medium supplemented with 3.0 mg/l 2,4-D for callus induction. The calli were transferred to MS medium supplemented with 5.0 mg/l IAA and 2.0 mg/l KIN for shoot regeneration. The shoots were rooted on MS medium supplemented with 5.0 mg/1NAA and 70 g/l sucrose. The regenerated plants were screened against red-rot disease and water-logged condition in a field. Of the 368 plants inoculated with red-rot pathogen, only one was moderately resistant and two were moderately susceptible. In another set of 500 R 1 plants, six clones were tolerant to water-logged condition. Four week-old callus cultures were irradiated with doses of 2, 3, 4, 5, 6, 7, 8 and 10 Gy gamma-rays. Survival of calli decreased with increase in radiation dose and ranged from 58 to 91%. Regenerated shoots were obtained from all irradiated calli except those treated with 8 and 10 Gy. Shoot regeneration from the irradiated calli ranged from 8 to 50%, and gave 768 R 1 plants. The highest regeneration of plants was obtained from calli treated with 3 Gy. These plants are being grown in a field for screening against red-rot and water-logged conditions. (author). 10 refs, 2 tabs

  3. Induction of somaclonal variation and mutations in sugarcane calli for selecting mutants with resistance to red-rot and tolerance to water-logged conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, M A.Q.; Begum, S; Samad, M A; Shmsuzzaman, K M [Bangladesh Inst. of Nuclear Agriculture, Mymensingh (Bangladesh)

    1997-07-01

    Immature leaves of cv. `Isd-16` of sugarcane were cultured on modified MS medium supplemented with 3.0 mg/l 2,4-D for callus induction. The calli were transferred to MS medium supplemented with 5.0 mg/l IAA and 2.0 mg/l KIN for shoot regeneration. The shoots were rooted on MS medium supplemented with 5.0 mg/1NAA and 70 g/l sucrose. The regenerated plants were screened against red-rot disease and water-logged condition in a field. Of the 368 plants inoculated with red-rot pathogen, only one was moderately resistant and two were moderately susceptible. In another set of 500 R{sub 1} plants, six clones were tolerant to water-logged condition. Four week-old callus cultures were irradiated with doses of 2, 3, 4, 5, 6, 7, 8 and 10 Gy gamma-rays. Survival of calli decreased with increase in radiation dose and ranged from 58 to 91%. Regenerated shoots were obtained from all irradiated calli except those treated with 8 and 10 Gy. Shoot regeneration from the irradiated calli ranged from 8 to 50%, and gave 768 R{sub 1} plants. The highest regeneration of plants was obtained from calli treated with 3 Gy. These plants are being grown in a field for screening against red-rot and water-logged conditions. (author). 10 refs, 2 tabs.

  4. Root (Botany)

    Science.gov (United States)

    Robert R. Ziemer

    1981-01-01

    Plant roots can contribute significantly to the stability of steep slopes. They can anchor through the soil mass into fractures in bedrock, can cross zones of weakness to more stable soil, and can provide interlocking long fibrous binders within a weak soil mass. In deep soil, anchoring to bedrock becomes negligible, and lateral reinforcement predominates

  5. Quorum sensing signaling molecules produced by reference and emerging soft-rot bacteria (Dickeya and Pectobacterium spp..

    Directory of Open Access Journals (Sweden)

    Alexandre Crépin

    Full Text Available Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates.Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase.Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the mechanisms of communication via the diffusible molecules

  6. Quorum Sensing Signaling Molecules Produced by Reference and Emerging Soft-Rot Bacteria (Dickeya and Pectobacterium spp.)

    Science.gov (United States)

    Crépin, Alexandre; Barbey, Corinne; Beury-Cirou, Amélie; Hélias, Valérie; Taupin, Laure; Reverchon, Sylvie; Nasser, William; Faure, Denis; Dufour, Alain; Orange, Nicole; Feuilloley, Marc; Heurlier, Karin; Burini, Jean-François; Latour, Xavier

    2012-01-01

    Background Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. Methodology/Principal Findings Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. Conclusions/Significance Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the

  7. Research on basal stem rot (BSR) of ornamental palms caused by basidiospores from Ganoderma boninense.

    Science.gov (United States)

    Lim, H P; Fong, Y K

    2005-01-01

    Basidiospores were isolated from the fruiting bodies of Ganoderma infecting oil palms from an estate in Johor and from ornamental palms (including oil palms) from Singapore. The spores were then germinated to obtain homokaryotic mycelia. Based on clamp connection formation in paired hyphal fusions, tester strains were identified from the homokaryons isolated. Compatibility tests were then carried out using these testers to determine the relatedness of the homokaryotic Ganoderma isolates, both from Johor and from Singapore. Results from the compatibility tests showed that Ganoderma from both locations belong to the same species, while the Ganoderma isolates from Singapore share some common alleles. The pathogenicity tests carried out on Chrysalidocarpus lutescens seedlings using inoculum growing on rubber wood blocks showed that dikaryotic mycelia can cause basal stem rot infection.

  8. 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

  9. Root diseases, climate change and biomass productivity

    International Nuclear Information System (INIS)

    Warren, G.R.; Cruickshank, M.

    2004-01-01

    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.

  10. Screening of resistance genes to fusarium root rot and fusarium wilt ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-10

    May 10, 2010 ... sequence for UBC 194 primer is: 5'-AGGACGTGCC-3'. The marker was amplified in 15 µL reaction volume containing 0.8 mM dNTPs,. 0.067 mM of primer, 2.6 mM MgSO4, 100 mM KCl, 100 mM. (NH4)2SO4, 200 mM Tris HCl (pH 8.75), 1% Triton X-100, 1 mg/ml. BSA and , 0.2 units of Taq polymerase with ...

  11. Antifungal effect of some plant extracts against factors wheat root rot

    Science.gov (United States)

    Atmaca, Sevim; Şimşek, Şeyda; Denek, Yunus Emre

    2017-04-01

    Methanol leaf extracts of Humulus lupulus L. and Achillea millefolium L. were evaluated for antifungal activity against economically important phytopathogenic fungi including Fusarium culmorum (W. G. Smith) Sacc. The final concentrations of the methanol extracts obtained from the plants were added to the Potato Dextrose Agar (PDA) at 1%, 2%, 4% and 8% doses. Mycelial disks of pathogens (6 mm in diameter) removed from the margins of a 7 days old culture were transferred to PDA media containing the plant extracts at tested concentrations. Four replicates were used per treatment. For each plant extract and concentration, inhibition of radial growth compared with the untreated control was calculated after 7 days of incubation at 24±1°C, in the dark. Extracts H. lupulus and A. millefolium inhibited the mycelial growth of F. culmorum of mycelial growth of 8% dose of the pathogens by 92.77% and 69.83%, respectively. It has been observed that the antifungal effect of the extracts increases with dose increase. As a result, at least micelle growth and the highest percent inhibition rate were obtained at 8% dose of the extract H. lupulus. H. lupulus extract can be used as a biological preparation.

  12. 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.

  13. Molecular characterization of a novel thermostable laccase PPLCC2 from the brown rot fungus Postia placenta MAD-698-R

    Directory of Open Access Journals (Sweden)

    Hongde An

    2015-11-01

    Conclusions: This is the first identified thermo activated and thermostable laccase in brown rot fungi. This investigation will contribute to understanding the roles played by laccases in brown rot fungi.

  14. Evaluating Genetic Association between Fusarium and Pythium ...

    African Journals Online (AJOL)

    Resistance to Fusarium root rot (Fusarium solani f.s.p phaseoli) has been reported in common bean (Phaseolus vulgaris L.) sources and is usually associated with Pythium root rot resistance. Pythium root rot (Pythium ultimum var ultimum) resistance is controlled by a single dominant gene, marked by a SCAR marker ...

  15. Fungi in neotropical epiphyte roots.

    Science.gov (United States)

    Bermudes, D; Benzing, D H

    1989-01-01

    Roots of thirty-eight Ecuadoran vascular epiphytes, representing eleven angiosperm families, were examined for the presence of symbiotic microorganisms. Most orchid roots contained fungal endophytes like those that regularly infect terrestrial counterparts. Hyphae were also common in and on nonorchid roots, but assignments of these relationships to known mycorrhizal morphologies was not possible in all cases. Evidence of vesicular-arbuscular mycorrhizae (VAM) existed in a number of subjects while in Ericaceae and Campanulaceae a fungal association similar to the demateaceous surface fungi (DSF) described for alpine and prarie plants was usually present. Some associations were characterized by multicellular propagules on root surfaces. The significance of these findings and the factors likely to influence occurrence and consequences of root-fungus mutualisms in tropical forest canopies are discussed. Facts and considerations that could aid future inquiry on these systems are provided.

  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. 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.

  18. Potential of bulb-associated bacteria for biocontrol of hyacinth soft rot caused by Dickeya zeae

    NARCIS (Netherlands)

    Jafra, S.; Przysowa, J.; Gwizdek-Wisniewska, A.; Wolf, van der J.M.

    2009-01-01

    Dickeya zeae is a pectinolytic bacterium responsible for soft rot disease in flower bulb crops. In this study, the possibility of controlling soft rot disease in hyacinth by using antagonistic bacteria isolated from hyacinth bulbs was explored. Bacterial isolates with potential for biocontrol were

  19. Effect of irradiation and insect pest control on rots and sensory ...

    African Journals Online (AJOL)

    The coffee bean weevil, Araecerus fasciculatus Degeer (Coleoptera: Curculionidae) is associated with rots in stored yam tubers. The current study was designed to assess the effect of irradiation and other insect pest control strategies on rots and sensory quality of stored yams. 450 tubers each of two varieties of white yam ...

  20. First report of Fusarium redolens causing crown rot of wheat (Triticum spp.) in Turkey

    Science.gov (United States)

    Fusarium crown rot, caused by a complex of Fusarium spp., is a yield-limiting disease of wheat world-wide, especially in dry Mediterranean climates. In order to identify Fusarium species associated with crown rot of wheat, a survey was conducted in summer 2013 in the major wheat growing regions of T...

  1. Studies on the epidemiology of spear rot in oil palm (Elaeis guineensis Jacq.) in Suriname

    NARCIS (Netherlands)

    Lande, van de H.L.

    1993-01-01

    The epidemiology of spear rot, an infectious disease of unknown etiology, was studied over 10 years at three government-owned oil palm plantations in Suriname. As with other and similar diseases, amarelecimento fatal in Brazil and pudrición del cogollo in Latin America, which too show rot

  2. Enzymatic oxalic acid regulation correlated with wood degradation in four brown-rot fungi

    Science.gov (United States)

    Anne Christine Steenkjær Hastrup; Frederick Green III; Patricia K. Lebow; Bo Jensen

    2012-01-01

    Oxalic acid is a key component in the initiation of brown-rot decay and it has been suggested that it plays multiple roles during the degradation process. Oxalic acid is accumulated to varying degrees among brown-rot fungi; however, details on active regulation are scarce. The accumulation of oxalic acid was measured in this study from wood degraded by the four brown-...

  3. Copper tolerance of brown-rot fungi : time course of oxalic acid production

    Science.gov (United States)

    Frederick Green; Carol A. Clausen

    2003-01-01

    The increase in the use of non-arsenical copper-based wood preservatives in response to environmental concerns has been accompanied by interest in copper-tolerant decay fungi. Oxalic acid production by brown-rot fungi has been proposed as one mechanism of copper tolerance. Fifteen brown-rot fungi representing the genera Postia, Wolfiporia, Meruliporia, Gloeophyllum,...

  4. Biocontrol of charcoal-rot of sorghum by actinomycetes isolated from ...

    African Journals Online (AJOL)

    use

    2011-12-12

    Dec 12, 2011 ... Streptomyces but with different species in BLAST analysis. This study indicates that the selected actinomycetes have the potential for PGP and control of charcoal-rot disease in sorghum. Key words: Antagonistic actinomycetes, biocontrol, charcoal-rot, Macrophomina phaseolina. INTRODUCTION.

  5. First report of Colletotrichum fructicola and C. queenslandicum causing fruit rot of rambutan (Nephelium lappaceum L.)

    Science.gov (United States)

    In rambutan production, fruit rot is the main pre- and post-harvest disease of concern. In a 2008-2013 fruit disease survey, fruit rot was observed in eight orchards in Puerto Rico. Infected fruit were collected and 1 mm2 tissue sections were surface disinfested with 70% ethanol followed by 0.5% sod...

  6. First Report of Calonectria hongkongensis Causing Fruit Rot of Rambutan (Nephelium lappaceum)

    NARCIS (Netherlands)

    Serrato-Diaz, L.M.; Latoni-Brailowsky, E.I.; Rivera-Vargas, L.I.; Goenaga, R.J.; Crous, P.W.; French-Monar, R.D.

    2013-01-01

    Fruit rot of rambutan is a pre- and post-harvest disease problem of rambutan orchards. In 2011, fruit rot was observed at USDA-ARS orchards in Mayaguez, Puerto Rico. Infected fruit were collected and 1 mm2 tissue sections were surface disinfested with 70% ethanol followed by 0.5% sodium

  7. 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. ...

  8. 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...

  9. Improving cost-effectiveness of brown rot control: the value of bio-economic modelling

    NARCIS (Netherlands)

    Breukers, A.; Werf, van der W.; Mourits, M.C.M.; Oude Lansink, A.G.J.M.

    2007-01-01

    Since 1995, the Dutch potato production chain has been hit by several outbreaks of brown rot, a quarantine disease caused by Ralstonia solanacearum race 3, biovar 2. To avoid establishment of brown rot in the potato production chain and avert the consequences on potato export, the Dutch government

  10. Fungicide rotation schemes for managing Phytophthora fruit rot of watermelon across southeastern United States

    Science.gov (United States)

    Southeastern states produce about 50% of the watermelons in the United States (U.S.) where conditions are optimal for development of Phytophthora fruit rot prevail. Phytophthora fruit rot significantly limits watermelon production by causing serious yield losses to growers before and after harvest. ...

  11. Resistance to post-harvest microbial rot in yam: Integration of ...

    African Journals Online (AJOL)

    Post-harvest microbial rot is an important disease that causes severe losses in yam (Dioscorea spp.) storage. Rot from microbial infection of healthy yam tubers reduces their table quality and renders them unappealing to consumers. A study was carried out at Bimbilla in the Nanumba North District of Ghana to evaluate ...

  12. First report of in-vitro fludioxonil-resistant isolates of Fusarium spp. causing potato dry rot in Michigan

    Science.gov (United States)

    Fusarium dry rot of potato (Solanum tuberosum) is a postharvest disease caused by several Fusarium species and is of worldwide importance. Measures for controlling dry rot in storage are limited. Dry rot has been managed primarily by reducing tuber bruising, providing conditions for rapid wound heal...

  13. 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

    -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 wood...

  14. Moniliophthora roreri, causal agent of cacao frosty pod rot.

    Science.gov (United States)

    Bailey, Bryan A; Evans, Harry C; Phillips-Mora, Wilbert; Ali, Shahin S; Meinhardt, Lyndel W

    2017-12-01

    Taxonomy: Moniliophthora roreri (Cif.) H.C. Evans et al. ; Phylum Basidiomycota; Class Agaricomycetes; Order Agaricales; Family Marasmiaceae; Genus Moniliophthora. Biology: Moniliophthora roreri attacks Theobroma and Herrania species causing frosty pod rot. Theobroma cacao (cacao) is the host of major economic concern. Moniliophthora roreri is a hemibiotroph with a long biotrophic phase (45-90 days). Spore masses, of apparent asexual origin, are produced on the pod surface after initiation of the necrotrophic phase. Spores are spread by wind, rain and human activity. Symptoms of the biotrophic phase can include necrotic flecks and, in some cases, pod malformation, but pods otherwise remain asymptomatic. Relationship to Moniliophthora perniciosa: Moniliophthora roreri and Moniliophthora perniciosa, causal agent of witches' broom disease of cacao, are closely related. Their genomes are similar, including many of the genes they carry which are considered to be important in the disease process. Moniliophthora perniciosa, also a hemibiotroph, has a typical basidiomycete lifestyle and morphology, forming clamp connections and producing mushrooms. Basidiospores infect meristematic tissues including flower cushions, stem tips and pods. Moniliophthora roreri does not form clamp connections or mushrooms and infects pods only. Both pathogens are limited to the Western Hemisphere and are a threat to cacao production around the world. Agronomic importance: Disease losses caused by frosty pod rot can reach 90% and result in field abandonment. Moniliophthora roreri remains in the invasive phase in the Western Hemisphere, not having reached Brazil, some islands within the Caribbean and a few specific regions within otherwise invaded countries. The disease can be managed by a combination of cultural (for example, maintenance of tree height and removal of infected pods) and chemical methods. These methods benefit from regional application, but can be cost prohibitive. Breeding for

  15. 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. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

    International Nuclear Information System (INIS)

    Weber, Z.; Fiszer, W.

    1991-01-01

    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

  17. Role of Rot in bacterial autolysis regulation of Staphylococcus aureus NCTC8325.

    Science.gov (United States)

    Chu, Xinmin; Xia, Rui; He, Nianan; Fang, Yuting

    2013-09-01

    Autolysis is an important process in cell wall turnover in Staphylococcus aureus, performed by several peptidoglycan hydrolases or so-called autolysins and controlled by many regulators. Rot is a global regulator that regulates numerous virulence genes, including genes encoding lipase, hemolysins, proteases and genes related to cell surface adhesion. The aim of our study was to determine whether Rot has the ability to regulate autolysis. We compared Triton-X-100-induced autolysis of S. aureus NCTC8325 and its rot knock-out mutant. We found that the rot mutant showed increased autolysis rates. By examining the transcript level of several autolysins and some known regulators responsible for regulating autolysis using real-time RT-PCR assays, we found that transcription of two autolysins (lytM, lytN) and one regulatory operon (lrgAB) was changed in the rot mutant. An in vitro approach was undertaken to determine which of these genes are directly controlled by Rot. Rot proteins were overproduced in Escherichia coli and purified. Gel mobility shift DNA binding assays were used and showed that in-vitro-purified Rot can directly bind to the promoter region of lytM, lytN, lrgA and lytS. We also tested biofilm formation of the rot mutant, and it showed enhancement in biofilm formation. Taken together, our results reveal that Rot affects autolysis by directly regulating autolysins LytM and LytN, and, via a regulatory system, LrgAB. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  18. Sclerotinia Rot on Basil Caused by Sclerotinia sclerotiorum in Korea

    Directory of Open Access Journals (Sweden)

    Soo Sang Hahm

    2017-03-01

    Full Text Available During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia (30–100 µm diameter formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and 5–50 µm diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

  19. Probing genetic diversity to characterize red rot resistance in sugarcane

    Energy Technology Data Exchange (ETDEWEB)

    Mumtaz, A S; Dure-e-Nayab,; Iqbal, M J; Shinwari, Z.K., E-mail: asmumtaz@qau.edu.pk

    2011-10-15

    Genetic diversity was assessed in a set of twelve sugarcane genotypes using Random Amplified Polymorphic DNA (RAPD). A total of thirty-two oligo-primers were employed, sixteen of them revealed amplification at 149 loci, out of which 136 were polymorphic. The genotype SPSG-26 showed the highest number of polymorphic loci, followed by CSSG-668 and HSF-242. Pairwise genetic similarity ranged from 67.2% to 83.3%. The UPGMA cluster analysis resolved most of the accessions in two groups. The clustering pattern did not place all resistant varieties in one or related group which depict diverse resistance source in the present set of sugarcane varieties. Ten primers revealed genotype specific bands among which four primers (K07, H02, K10 and F01) produced multiple genotype specific bands that aid genotype identification especially those with red rot resistance. The present study not only provided information on the genetic diversity among the genotypes but also revealed the potential of RAPD-PCR markers for genotype identification and therefore could be utilized in marker assisted selection for red rot resistance in sugarcane. (author)

  20. RootJS: Node.js Bindings for ROOT 6

    Science.gov (United States)

    Beffart, Theo; Früh, Maximilian; Haas, Christoph; Rajgopal, Sachin; Schwabe, Jonas; Wolff, Christoph; Szuba, Marek

    2017-10-01

    We present rootJS, an interface making it possible to seamlessly integrate ROOT 6 into applications written for Node.js, the JavaScript runtime platform increasingly commonly used to create high-performance Web applications. ROOT features can be called both directly from Node.js code and by JIT-compiling C++ macros. All rootJS methods are invoked asynchronously and support callback functions, allowing non-blocking operation of Node.js applications using them. Last but not least, our bindings have been designed to platform-independent and should therefore work on all systems supporting both ROOT 6 and Node.js. Thanks to rootJS it is now possible to create ROOT-aware Web applications taking full advantage of the high performance and extensive capabilities of Node.js. Examples include platforms for the quality assurance of acquired, reconstructed or simulated data, book-keeping and e-log systems, and even Web browser-based data visualisation and analysis.

  1. Draft Genome Sequence of Bacillus velezensis 3A-25B, a Strain with Biocontrol Activity against Fungal and Oomycete Root Plant Phytopathogens, Isolated from Grassland Soil.

    Science.gov (United States)

    Martínez-Raudales, Inés; De La Cruz-Rodríguez, Yumiko; Vega-Arreguín, Julio; Alvarado-Gutiérrez, Alejandro; Fraire-Mayorga, Atzin; Alvarado-Rodríguez, Miguel; Balderas-Hernández, Victor; Gómez-Soto, José Manuel; Fraire-Velázquez, Saúl

    2017-09-28

    Here, we present the draft genome of Bacillus velezensis 3A-25B, which totaled 4.01 Mb with 36 contigs, 3,948 genes, and a GC content of 46.34%. This strain, which demonstrates biocontrol activity against root rot causal phytopathogens in horticultural crops and friendly interactions in roots of pepper plantlets, was obtained from grassland soil in Zacatecas Province, Mexico. Copyright © 2017 Martínez-Raudales et al.

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

    International Nuclear Information System (INIS)

    Ajanga, S.I.

    2002-01-01

    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

  3. Simultaneous Detection of Brown Rot- and Soft Rot-Causing Bacterial Pathogens from Potato Tubers Through Multiplex PCR.

    Science.gov (United States)

    Ranjan, R K; Singh, Dinesh; Baranwal, V K

    2016-11-01

    Ralstonia solanacearum (Smith) Yabuuchi et al. and Erwinia carotovora subsp. carotovora (Jones) Bergey et al. (Pectobacterium carotovorum subsp. carotovorum) are the two major bacterial pathogens of potato causing brown rot (wilt) and soft rot diseases, respectively, in the field and during storage. Reliable and early detection of these pathogens are keys to avoid occurrence of these diseases in potato crops and reduce yield loss. In the present study, multiplex polymerase chain reaction (PCR) protocol was developed for simultaneous detection of R. solanacearum and E. carotovora subsp. carotovora from potato tubers. A set of oligos targeting the pectatelyase (pel) gene of E. carotovora subsp. carotovora and the universal primers based on 16S r RNA gene of R. solanacearum were used. The standardized multiplex PCR protocol could detect R. solanacearum and E. carotovora subsp. carotovora up to 0.01 and 1.0 ng of genomic DNA, respectively. The protocol was further validated on 96 stored potato tuber samples, collected from different potato-growing states of India, viz. Uttarakhand, Odisha, Meghalaya and Delhi. 53.1 % tuber samples were positive for R. solanacearum, and 15.1 % of samples were positive for E. carotovora subsp. carotovora, and both the pathogens were positive in 26.0 % samples when BIO-PCR was used. This method offers sensitive, specific, reliable and fast detection of two major bacterial pathogens from potato tubers simultaneously, particularly pathogen-free seed certification in large scale.

  4. Root coverage with bridge flap

    Directory of Open Access Journals (Sweden)

    Pushpendra Kumar Verma

    2013-01-01

    Full Text Available Gingival recession in anterior teeth is a common concern due to esthetic reasons or root sensitivity. Gingival recession, especially in multiple anterior teeth, is of huge concern due to esthetic reasons. Various mucogingival surgeries are available for root coverage. This case report presents a new bridge flap technique, which allows the dentist not only to cover the previously denuded root surfaces but also to increase the zone of attached gingiva at a single step. In this case, a coronally advanced flap along with vestibular deepening technique was used as root coverage procedure for the treatment of multiple recession-type defect. Here, vestibular deepening technique is used to increase the width of the attached gingiva. The predictability of this procedure results in an esthetically healthy periodontium, along with gain in keratinized tissue and good patient′s acceptance.

  5. Structure of Rot, a global regulator of virulence genes in Staphylococcus aureus.

    Science.gov (United States)

    Zhu, Yuwei; Fan, Xiaojiao; Zhang, Xu; Jiang, Xuguang; Niu, Liwen; Teng, Maikun; Li, Xu

    2014-09-01

    Staphylococcus aureus is a highly versatile pathogen that can infect human tissue by producing a large arsenal of virulence factors that are tightly regulated by a complex regulatory network. Rot, which shares sequence similarity with SarA homologues, is a global regulator that regulates numerous virulence genes. However, the recognition model of Rot for the promoter region of target genes and the putative regulation mechanism remain elusive. In this study, the 1.77 Å resolution X-ray crystal structure of Rot is reported. The structure reveals that two Rot molecules form a compact homodimer, each of which contains a typical helix-turn-helix module and a β-hairpin motif connected by a flexible loop. Fluorescence polarization results indicate that Rot preferentially recognizes AT-rich dsDNA with ~30-base-pair nucleotides and that the conserved positively charged residues on the winged-helix motif are vital for binding to the AT-rich dsDNA. It is proposed that the DNA-recognition model of Rot may be similar to that of SarA, SarR and SarS, in which the helix-turn-helix motifs of each monomer interact with the major grooves of target dsDNA and the winged motifs contact the minor grooves. Interestingly, the structure shows that Rot adopts a novel dimerization model that differs from that of other SarA homologues. As expected, perturbation of the dimer interface abolishes the dsDNA-binding ability of Rot, suggesting that Rot functions as a dimer. In addition, the results have been further confirmed in vivo by measuring the transcriptional regulation of α-toxin, a major virulence factor produced by most S. aureus strains.

  6. A Genome-Wide Association Study Reveals Genes Associated with Fusarium Ear Rot Resistance in a Maize Core Diversity Panel

    Science.gov (United States)

    Zila, Charles T.; Samayoa, L. Fernando; Santiago, Rogelio; Butrón, Ana; Holland, James B.

    2013-01-01

    Fusarium ear rot is a common disease of maize that affects food and feed quality globally. Resistance to the disease is highly quantitative, and maize breeders have difficulty incorporating polygenic resistance alleles from unadapted donor sources into elite breeding populations without having a negative impact on agronomic performance. Identification of specific allele variants contributing to improved resistance may be useful to breeders by allowing selection of resistance alleles in coupling phase linkage with favorable agronomic characteristics. We report the results of a genome-wide association study to detect allele variants associated with increased resistance to Fusarium ear rot in a maize core diversity panel of 267 inbred lines evaluated in two sets of environments. We performed association tests with 47,445 single-nucleotide polymorphisms (SNPs) while controlling for background genomic relationships with a mixed model and identified three marker loci significantly associated with disease resistance in at least one subset of environments. Each associated SNP locus had relatively small additive effects on disease resistance (±1.1% on a 0–100% scale), but nevertheless were associated with 3 to 12% of the genotypic variation within or across environment subsets. Two of three identified SNPs colocalized with genes that have been implicated with programmed cell death. An analysis of associated allele frequencies within the major maize subpopulations revealed enrichment for resistance alleles in the tropical/subtropical and popcorn subpopulations compared with other temperate breeding pools. PMID:24048647

  7. Neofusicoccum luteum associated with leaf necrosis and fruit rot of olives in New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    V. Sergeeva

    2009-09-01

    Full Text Available Neofusicoccum luteum is reported for the first time from olives (Olea europaea, causing fruit rot and leaf necrosis. Affected fruits initially became brown with pycnidia developing on the surface, later drying out and becoming mummified. The fungus was shown to be pathogenic on both fruits and leaves. The association of Botryosphaeriaceae with rotting olive fruits in Mediterranean regions and in New South Wales, Australia indicates that these fungi play a significant role in fruit rots of olives and deserve greater attention.

  8. Control of Ralstonia Solanacearum The Causal Agent of Brown Rot in Potato Using Essential Oils

    International Nuclear Information System (INIS)

    Salem, E.A.

    2011-01-01

    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.

  9. Internal Rot Detection with the Use of Low-Frequency Flaw Detector

    Science.gov (United States)

    Proskórnicki, Marek; Ligus, Grzegorz

    2014-12-01

    The issue of rot detection in standing timber or stocked wood is very important in forest management. Rot flaw detection used for that purpose is represented by invasive and non-invasive devices. Non-invasive devices are very accurate, but due to the cost and complicated operation they have not been applied on a large scale in forest management. Taking into account the practical needs of foresters a prototype of low-frequency flaw was developed. The principle of its operation is based on the difference in acoustic wave propagation in sound wood and wood with rot.

  10. How to study deep roots - and why it matters

    OpenAIRE

    Maeght, Jean-Luc; Rewald, B.; Pierret, Alain

    2013-01-01

    The drivers underlying the development of deep root systems, whether genetic or environmental, are poorly understood but evidence has accumulated that deep rooting could be a more widespread and important trait among plants than commonly anticipated from their share of root biomass. Even though a distinct classification of "deep roots" is missing to date, deep roots provide important functions for individual plants such as nutrient and water uptake but can also shape plant communities by hydr...

  11. Plasmonic coaxial Fabry-Pérot nanocavity color filter

    Science.gov (United States)

    Si, G. Y.; Leong, E. S. P.; Danner, A. J.; Teng, J. H.

    2010-08-01

    Plamonic coaxial structures have drawn considerable attetion recently because of their unique properties. They exhibit different mechanisms of extraordinary optical transmission observed from subwavelength holes and they can support localized Fabry-Pérot plasmon modes. In this work, we experimentally demonstrate color filters based on coaxial structures fabricated in optically thick metallic films. Using nanogaps with different apertures from 160 nm down to only 40 nm, we show varying color outputs when the annular aperture arrays are illuminated with a broadband light source. Effective color-filter function is demonstrated in the optical regime. Different color outputs are observed and optical spectra are measured. In such structures, it is the propagating mode playing an important role rather than the evanescent. Resonances depend strongly on ring apertures, enabling devices with tunability of output colors using simple geometry control.

  12. Saturnispora bothae sp. nov., isolated from rotting wood.

    Science.gov (United States)

    Morais, Camila G; Lara, Carla A; Borelli, Beatriz M; Cadete, Raquel M; Moreira, Juliana D; Lachance, Marc-André; Rosa, Carlos A

    2016-10-01

    Two strains representing a novel species of the genus Saturnispora were isolated from rotting wood samples collected in an Atlantic Rainforest site in Brazil. Analyses of the sequences of the D1/D2 domains of the rRNA gene showed that this novel species belongs to a subclade in the Saturnispora clade formed by Saturnispora sanitii, Saturnispora sekii, Saturnispora silvae and Saturnisporasuwanaritii. The novel species differed in D1/D2 sequences by 60 or more nucleotide substitutions from these species. The strains produced asci with one to four hemispherical ascospores. A novel species named Saturnispora bothae sp. nov. is proposed to accommodate these isolates. The type strain is UFMG-CM-Y292T (=CBS 13484T). The MycoBank number is MB 817127.

  13. First report of alfalfa (Medicago sativa L.) seed rot, seedling root rot, and damping off caused by Pythium spp. in Sudanese soil

    Science.gov (United States)

    Alfalfa is an important forage crop in Sudan but has relatively low biomass yields. In September 2016 soil samples were collected from three commercial alfalfa production fields near Khartoum, Sudan with poor seedling establishment and rapid stand decline. Soil samples from each field were evaluated...

  14. Control of yam tuber rot with leaf extracts of Xylopia aethiopica and ...

    African Journals Online (AJOL)

    JOHN

    Investigation was carried out to test the potency of some plant extracts for the control of yam tuber rot caused by Fusarium ... The extracts of suppressed the growth of these fungi in culture ..... Methodolgy for analysis of Vegetable drug. Practical.

  15. Biodegradation of hazardous waste using white rot fungus: Project planning and concept development document

    International Nuclear Information System (INIS)

    Luey, J.; Brouns, T.M.; Elliott, M.L.

    1990-11-01

    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

  16. Assessment of Sugarcane Germplasm ( Saccharum spp. complex Against Red Rot Pathogen Colletotrichum Falcatum

    Directory of Open Access Journals (Sweden)

    Atul Singh

    2017-08-01

    Full Text Available ABSTRACT Red rot, caused by Colletotrichum falcatum Went is the most important disease of sugarcane in India inflicting substantial loss to both cane industry and cane growers. To keep in view the importance of red rot disease of sugarcane, 117 accession of sugarcane germplasm including different Saccharum species and Indian and foreign commercial hybrids were tested against red rot with Cf 07, Cf 08 & Cf 09 (national pathotypes by plug method of inoculation. Out of 117, 6 were found resistant and 12 were moderately resistant against red rot and rest were moderately susceptible/susceptible/highly susceptible. Theses resistance and moderately resistant accession can be further utilize to produce resistance varieties against the most devastating pathogen of sugarcane.

  17. 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.

  18. Development of sugarcane mutants with resistance to red rot, water-logging and delayed or non-flowering through induced mutations

    International Nuclear Information System (INIS)

    Majid, M.A.; Shamsuzzaman, K.M.; Howlider, M.A.R.; Islam, M.M.

    2001-01-01

    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 MV 2 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 MV 3 hills, inoculated with red rot spore suspension, 37 resistant and 151 moderately resistant plants were isolated. Selection was carried out in the MV 4 to MV 7 propagation. Seven MV 7 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 MV 3 canes were planted in a low-lying field, and subjected to water-logging stress. MV 5 and MV 6 populations were inoculated with red rot spore- suspension under waterlogged conditions. Five MV 5 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 MV 6 propagation. Three selected variants, SCM-12, SCM-14 and SCM-15, were tolerant to waterlogged conditions in MV 6 . 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 MV 3 for delayed flowering; one mutant, SCM-28 flowered three months later than the parent 'I-291/87'. (author)

  19. Combined effects of biocontrol agents and soil amendments on soil microbial populations, plant growth and incidence of charcoal rot of cowpea and wilt of cumin

    Directory of Open Access Journals (Sweden)

    Vijeta SINGH

    2012-09-01

    Full Text Available Field experiments were conducted for 2 years to determine the effectiveness of combined use of two biocontrol agents, Bacillus firmus and Aspergillus versicolor for control of Macrophomina phaseolina induced charcoal rot of cowpea and Fusarium oxysporum f. sp. cumini induced wilt of cumin. The lowest level of plant mortality (3‒4% due to charcoal rot of cowpea was recorded when bacterium coated seeds were sown in radish compost amended soil compared to the non-amended soil (13.8‒20.5%, but this was not significantly better than some other treatments. Cowpea roots from B. firmus coated seeds had better nodulation than any of the individual A. versicolor treatments. Although B. firmus coated seeds + A. versicolor + farmyard manure resulted in maximum nodulation this was not significantly different to B. firmus seed coating. Root colonization by the combined biocontrol agent treatments was better than the individual biocontrol agent treatments. Combining A. versicolor with farmyard manure supported the maximum populations of total fungi and actinomycetes. In both winter seasons, the lowest incidence of wilt (1.0‒5.2% on cumin was recorded when A. versicolor was amended with neem compost compared to the non-amended soil (5.7‒10.5%. Maximum colonization of A. versicolor on roots was observed in B. firmus + A. versicolor + farmyard manure amended plots. During both years, the treatment combination of A. versicolor in neem compost amended plots resulted in maximum populations of fungi, bacteria and A. versicolor in the soil, which was greater than in the non-amended soil. Significant increases in disease control were not recorded after single or repeated delivery of A. versicolor. These results suggest that combining B. firmus as seed coatings with A. versicolor as soil applications gives improved control of M. phaseolina and Fusarium induced diseases on legume and seed spice crops in arid soils.

  20. 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.

  1. Rapid polyether cleavage via extracellular one-electron oxidation by a brown-rot basidiomycete

    OpenAIRE

    Kerem, Zohar; Bao, Wuli; Hammel, Kenneth E.

    1998-01-01

    Fungi that cause brown rot of wood are essential biomass recyclers and also the principal agents of decay in wooden structures, but the extracellular mechanisms by which they degrade lignocellulose remain unknown. To test the hypothesis that brown-rot fungi use extracellular free radical oxidants as biodegradative tools, Gloeophyllum trabeum was examined for its ability to depolymerize an environmentally recalcitrant polyether, poly(ethylene oxide) (PEO), that cannot penetrate cell membranes....

  2. Effectiveness of Neutral Electrolyzed Water on Incidence of Fungal Rot on Tomato Fruits ( Solanum lycopersicum L.).

    Science.gov (United States)

    Vásquez-López, Alfonso; Villarreal-Barajas, Tania; Rodríguez-Ortiz, Gerardo

    2016-10-01

    We assessed the effect of neutral electrolyzed water (NEW) on the incidence of rot on tomato ( Solanum lycopersicum L.) fruits inoculated with Fusarium oxysporum , Galactomyces geotrichum , and Alternaria sp. at sites with lesions. The inoculated fruits were treated with NEW at 10, 30, and 60 mg liter -1 active chlorine, with copper oxychloride fungicide, and with sterile distilled water (control) for 3, 5, and 10 min. In the experiment with F. oxysporum , 50 to 80% of the control fruits and 50 to 60% of the fruits treated with the fungicide exhibited symptoms of rot at the inoculated sites. The lowest incidence recorded was 30% for fruits treated with NEW at 60 mg liter -1 active chlorine with an immersion time of 5 min. In the experiment with G. geotrichum , incidence of rot on control fruits was 70 to 90%, and for treatment with fungicide rot incidence was 50 to 90%. NEW at 60 mg liter -1 active chlorine significantly reduced incidence of symptomatic fruit: only 30% of the inoculated fruits washed for 5 min had damage from rot. In the experiment with Alternaria sp., 60 to 90% of the fruits in the control group and 60 to 70% of the fruits in the fungicide group were symptomatic. The lowest incidence was recorded for the treatment in which the fruits were submerged in NEW with 60 mg liter -1 active chlorine for 3 min. In this group, 40 to 50% of the fruits exhibited symptoms of rot. These results were obtained 8 days after inoculation. NEW, with 60 mg liter -1 active chlorine, significantly reduced incidence of rot symptoms on fruits inoculated with one of the experimental fungi relative to the control (P ≤ 0.05). NEW at 60 mg liter -1 is effective in the control of fungal rot in tomatoes.

  3. Hendersonia Creberrima, the cause of soft brown rot of mango in South Africa

    International Nuclear Information System (INIS)

    Brodrick, H.T.; Van der westhuizen, G.C.A.

    1976-01-01

    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 11 0 C 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

  4. A system for predicting the amount of Phellinus (Fomes) igniarius rot in trembling aspen stands

    Science.gov (United States)

    Robert L. Anderson; Arthur L. Jr. Schipper

    1978-01-01

    The occurrence of Phellinus (Fomes) igniarius white trunk rot in 45- to 50-year-old trembling aspen stands can be predicted by applying a constant to the stand basal area with P. igniarius conks to estimate the total basal area with P. igniarius rot. Future decay projections can be made by reapplying the basal area of hidden decay for each 6 years projected. This paper...

  5. Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)

    Science.gov (United States)

    Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R.

    2018-01-01

    Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea. PMID:29444142

  6. Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum).

    Science.gov (United States)

    Šišić, Adnan; Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R

    2018-01-01

    Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.

  7. Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum.

    Directory of Open Access Journals (Sweden)

    Adnan Šišić

    Full Text Available Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.

  8. A statistical approach to root system classification.

    Directory of Open Access Journals (Sweden)

    Gernot eBodner

    2013-08-01

    Full Text Available Plant root systems have a key role in ecology and agronomy. In spite of fast increase in root studies, still there is no classification that allows distinguishing among distinctive characteristics within the diversity of rooting strategies. Our hypothesis is that a multivariate approach for plant functional type identification in ecology can be applied to the classification of root systems. We demonstrate that combining principal component and cluster analysis yields a meaningful classification of rooting types based on morphological traits. The classification method presented is based on a data-defined statistical procedure without a priori decision on the classifiers. Biplot inspection is used to determine key traits and to ensure stability in cluster based grouping. The classification method is exemplified with simulated root architectures and morphological field data. Simulated root architectures showed that morphological attributes with spatial distribution parameters capture most distinctive features within root system diversity. While developmental type (tap vs. shoot-borne systems is a strong, but coarse classifier, topological traits provide the most detailed differentiation among distinctive groups. Adequacy of commonly available morphologic traits for classification is supported by field data. Three rooting types emerged from measured data, distinguished by diameter/weight, density and spatial distribution respectively. Similarity of root systems within distinctive groups was the joint result of phylogenetic relation and environmental as well as human selection pressure. We concluded that the data-define classification is appropriate for integration of knowledge obtained with different root measurement methods and at various scales. Currently root morphology is the most promising basis for classification due to widely used common measurement protocols. To capture details of root diversity efforts in architectural measurement

  9. Soft rot decay capabilities and interactions of fungi and bacteria from fumigated utility poles

    International Nuclear Information System (INIS)

    Wang, C.J.K.; Worrall, J.J.

    1992-11-01

    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

  10. ROOT Reference Documentation

    CERN Document Server

    Fuakye, Eric Gyabeng

    2017-01-01

    A ROOT Reference Documentation has been implemented to generate all the lists of libraries needed for each ROOT class. Doxygen has no option to generate or add the lists of libraries for each ROOT class. Therefore shell scripting and a basic C++ program was employed to import the lists of libraries needed by each ROOT class.

  11. Comparative Examination of the Olive Mill Wastewater Biodegradation Process by Various Wood-Rot Macrofungi

    Science.gov (United States)

    Koutrotsios, Georgios; Zervakis, Georgios I.

    2014-01-01

    Olive mill wastewater (OMW) constitutes a major cause of environmental pollution in olive-oil producing regions. Sixty wood-rot macrofungi assigned in 43 species were evaluated for their efficacy to colonize solidified OMW media at initially established optimal growth temperatures. Subsequently eight strains of the following species were qualified: Abortiporus biennis, Ganoderma carnosum, Hapalopilus croceus, Hericium erinaceus, Irpex lacteus, Phanerochaete chrysosporium, Pleurotus djamor, and P. pulmonarius. Fungal growth in OMW (25%v/v in water) resulted in marked reduction of total phenolic content, which was significantly correlated with the effluent's decolorization. A. biennis was the best performing strain (it decreased phenolics by 92% and color by 64%) followed by P. djamor and I. lacteus. Increase of plant seeds germination was less pronounced evidencing that phenolics are only partly responsible for OMW's phytotoxicity. Laccase production was highly correlated with all three biodegradation parameters for H. croceus, Ph. chrysosporium, and Pleurotus spp., and so were manganese-independent and manganese dependent peroxidases for A. biennis and I. lacteus. Monitoring of enzymes with respect to biomass production indicated that Pleurotus spp., H. croceus, and Ph. chrysosporium shared common patterns for all three activities. Moreover, generation of enzymes at the early biodegradation stages enhanced the efficiency of OMW treatment. PMID:24987685

  12. Comparative Examination of the Olive Mill Wastewater Biodegradation Process by Various Wood-Rot Macrofungi

    Directory of Open Access Journals (Sweden)

    Georgios Koutrotsios

    2014-01-01

    Full Text Available Olive mill wastewater (OMW constitutes a major cause of environmental pollution in olive-oil producing regions. Sixty wood-rot macrofungi assigned in 43 species were evaluated for their efficacy to colonize solidified OMW media at initially established optimal growth temperatures. Subsequently eight strains of the following species were qualified: Abortiporus biennis, Ganoderma carnosum, Hapalopilus croceus, Hericium erinaceus, Irpex lacteus, Phanerochaete chrysosporium, Pleurotus djamor, and P. pulmonarius. Fungal growth in OMW (25%v/v in water resulted in marked reduction of total phenolic content, which was significantly correlated with the effluent’s decolorization. A. biennis was the best performing strain (it decreased phenolics by 92% and color by 64% followed by P. djamor and I. lacteus. Increase of plant seeds germination was less pronounced evidencing that phenolics are only partly responsible for OMW’s phytotoxicity. Laccase production was highly correlated with all three biodegradation parameters for H. croceus, Ph. chrysosporium, and Pleurotus spp., and so were manganese-independent and manganese dependent peroxidases for A. biennis and I. lacteus. Monitoring of enzymes with respect to biomass production indicated that Pleurotus spp., H. croceus, and Ph. chrysosporium shared common patterns for all three activities. Moreover, generation of enzymes at the early biodegradation stages enhanced the efficiency of OMW treatment.

  13. Fusarium proliferatum - Causal agent of garlic bulb rot in Spain: Genetic variability and mycotoxin production.

    Science.gov (United States)

    Gálvez, Laura; Urbaniak, Monika; Waśkiewicz, Agnieszka; Stępień, Łukasz; Palmero, Daniel

    2017-10-01

    Fusarium proliferatum is a world-wide occurring fungal pathogen affecting several crops included garlic bulbs. In Spain, this is the most frequent pathogenic fungus associated with garlic rot during storage. Moreover, F. proliferatum is an important mycotoxigenic species, producing a broad range of toxins, which may pose a risk for food safety. The aim of this study is to assess the intraspecific variability of the garlic pathogen in Spain implied by analyses of translation elongation factor (tef-1α) and FUM1 gene sequences as well as the differences in growth rates. Phylogenetic characterization has been complemented with the characterization of mating type alleles as well as the species potential as a toxin producer. Phylogenetic trees based on the sequence of the translation elongation factor and FUM1 genes from seventy nine isolates from garlic revealed a considerable intraspecific variability as well as high level of diversity in growth speed. Based on the MAT alleles amplified by PCR, F. proliferatum isolates were separated into different groups on both trees. All isolates collected from garlic in Spain proved to be fumonisin B 1 , B 2 , and B 3 producers. Quantitative analyses of fumonisins, beauvericin and moniliformin (common secondary metabolites of F. proliferatum) showed no correlation with phylogenetic analysis neither mycelial growth. This pathogen presents a high intraspecific variability within the same geographical region and host, which is necessary to be considered in the management of the disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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 out region of E. carotovora subsp. carotovora and by complementation of Out- mutants of E. carotovora subsp. carotovora. Out- mutants of Ecb168, which did not secrete pectate lyase into the culture medium, were obtained when deletions internal to either HindIII fragment were introduced into the genome of Ecb168 through marker exchange mutagenesis. Out- mutants of Ecb168 were complemented to the Out+ phenotype by introduction of the corresponding cloned HindIII fragment. Out- mutants of Ecb168 were less virulent than the Out+ parental strain on potato tubers. Strain Ecb168 and Out- derivatives inhibited the growth of E. carotovora subsp. carotovora in culture, indicating that the uncharacterized antibiotic(s) responsible for antagonism was exported through an out-independent mechanism. Strain Ecb168 and Out- derivatives reduced the establishment of large populations of E. carotovora subsp. carotovora in wounds of potato tubers and suppressed tuber soft rot caused by E. carotovora subsp. carotovora. PMID:16349316

  15. Study on the Occurrence and Epidemic Model of Rape Sclerotinia Stem Rot of ‘Zheyou 50’

    OpenAIRE

    Xu Sen-fu; Wang Hui-fu; Yu Shanhong; Wang En-guo

    2013-01-01

    In order to investigate invading and epidemic rules of rape sclerotinia stem rot of ‘Zheyou 50’ and promote the development of brassica campestris industry, this paper studied the outbreak regularity and epidemic model of rape sclerotinia stem rot according to field investigation and infection. The result showed that machinery direct seeding rape was good for the occurrence of sclerotinia stem rot for the reason of late seeding and high density. The period from water damage appeared to wiltin...

  16. Development of TRatioPlot in ROOT

    CERN Document Server

    Gessinger-Befurt, Paul

    2016-01-01

    The ROOT data analysis and visualization framework is a software package which is widely used in physics, especially in high energy physics. A common visualization which has so far been lacking a direct implementation is the ratio plot, as well as a few similar types of plots. The scope and goal of the summer student project at CERN was to implement a class in ROOT itself, that can take care of the most common types of calculations, and produces high quality visuals.

  17. 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...

  18. Root exudates from grafted-root watermelon showed a certain contribution in inhibiting Fusarium oxysporum f. sp. niveum.

    Directory of Open Access Journals (Sweden)

    Ning Ling

    Full Text Available Grafting watermelon onto bottle gourd rootstock is commonly used method to generate resistance to Fusarium oxysporum f. sp. niveum (FON, but knowledge of the effect of the root exudates of grafted watermelon on this soil-borne pathogen in rhizosphere remains limited. To investigate the root exudate profiles of the own-root bottle gourd, grafted-root watermelon and own-root watermelon, recirculating hydroponic culture system was developed to continuously trap these root exudates. Both conidial germination and growth of FON were significantly decreased in the presence of root exudates from the grafted-root watermelon compared with the own-root watermelon. HPLC analysis revealed that the composition of the root exudates released by the grafted-root watermelon differed not only from the own-root watermelon but also from the bottle gourd rootstock plants. We identified salicylic acid in all 3 root exudates, chlorogenic acid and caffeic acid in root exudates from own-root bottle gourd and grafted-root watermelon but not own-root watermelon, and abundant cinnamic acid only in own-root watermelon root exudates. The chlorogenic and caffeic acid were candidates for potentiating the enhanced resistance of the grafted watermelon to FON, therefore we tested the effects of the two compounds on the conidial germination and growth of FON. Both phenolic acids inhibited FON conidial germination and growth in a dose-dependent manner, and FON was much more susceptible to chlorogenic acid than to caffeic acid. In conclusion, the key factor in attaining the resistance to Fusarium wilt is grafting on the non-host root stock, however, the root exudates profile also showed some contribution in inhibiting FON. These results will help to better clarify the disease resistance mechanisms of grafted-root watermelon based on plant-microbe communication and will guide the improvement of strategies against Fusarium-mediated wilt of watermelon plants.

  19. 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

  20. Differences in crystalline cellulose modification due to degradation by brown and white rot fungi.

    Science.gov (United States)

    Hastrup, Anne Christine Steenkjær; Howell, Caitlin; Larsen, Flemming Hofmann; Sathitsuksanoh, Noppadon; Goodell, Barry; Jellison, Jody

    2012-10-01

    Wood-decaying basidiomycetes are some of the most effective bioconverters of lignocellulose in nature, however the way they alter wood crystalline cellulose on a molecular level is still not well understood. To address this, we examined and compared changes in wood undergoing decay by two species of brown rot fungi, Gloeophyllum trabeum and Meruliporia incrassata, and two species of white rot fungi, Irpex lacteus and Pycnoporus sanguineus, using X-ray diffraction (XRD) and (13)C solid-state nuclear magnetic resonance (NMR) spectroscopy. The overall percent crystallinity in wood undergoing decay by M. incrassata, G. trabeum, and I. lacteus appeared to decrease according to the stage of decay, while in wood decayed by P. sanguineus the crystallinity was found to increase during some stages of degradation. This result is suggested to be potentially due to the different decay strategies employed by these fungi. The average spacing between the 200 cellulose crystal planes was significantly decreased in wood degraded by brown rot, whereas changes observed in wood degraded by the two white rot fungi examined varied according to the selectivity for lignin. The conclusions were supported by a quantitative analysis of the structural components in the wood before and during decay confirming the distinct differences observed for brown and white rot fungi. The results from this study were consistent with differences in degradation methods previously reported among fungal species, specifically more non-enzymatic degradation in brown rot versus more enzymatic degradation in white rot. Copyright © 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  1. Interactions of Salmonella enterica Serovar Typhimurium and Pectobacterium carotovorum within a Tomato Soft Rot.

    Science.gov (United States)

    George, Andrée S; Cox, Clayton E; Desai, Prerak; Porwollik, Steffen; Chu, Weiping; de Moraes, Marcos H; McClelland, Michael; Brandl, Maria T; Teplitski, Max

    2018-03-01

    Salmonella spp. are remarkably adaptable pathogens, and this adaptability allows these bacteria to thrive in a variety of environments and hosts. The mechanisms with which these pathogens establish within a niche amid the native microbiota remain poorly understood. Here, we aimed to uncover the mechanisms that enable Salmonella enterica serovar Typhimurium strain ATCC 14028 to benefit from the degradation of plant tissue by a soft rot plant pathogen, Pectobacterium carotovorum The hypothesis that in the soft rot, the liberation of starch (not utilized by P. carotovorum ) makes this polymer available to Salmonella spp., thus allowing it to colonize soft rots, was tested first and proven null. To identify the functions involved in Salmonella soft rot colonization, we carried out transposon insertion sequencing coupled with the phenotypic characterization of the mutants. The data indicate that Salmonella spp. experience a metabolic shift in response to the changes in the environment brought on by Pectobacterium spp. and likely coordinated by the csrBC small regulatory RNA. While csrBC and flhD appear to be of importance in the soft rot, the global two-component system encoded by barA sirA (which controls csrBC and flhDC under laboratory conditions) does not appear to be necessary for the observed phenotype. Motility and the synthesis of nucleotides and amino acids play critical roles in the growth of Salmonella spp. in the soft rot. IMPORTANCE Outbreaks of produce-associated illness continue to be a food safety concern. Earlier studies demonstrated that the presence of phytopathogens on produce was a significant risk factor associated with increased Salmonella carriage on fruits and vegetables. Here, we genetically characterize some of the requirements for interactions between Salmonella and phytobacteria that allow Salmonella spp. to establish a niche within an alternate host (tomato). Pathways necessary for nucleotide synthesis, amino acid synthesis, and motility

  2. Variations in the Root Form and Root Canal Morphology of Permanent Mandibular First Molars in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Roshan Peiris

    2015-01-01

    Full Text Available The present study was conducted to determine the number of roots and morphology of the root canal system of permanent mandibular first molars (M1 in a Sri Lankan population. Sample of 529 M1 teeth was used. The number of roots was examined and the lengths of the mesial and distal roots were measured to the nearest 0.01 mm. Vacuum injection protocol was used to inject China ink into the root canal system, making it transparent. Root canal morphology was recorded using Vertucci’s classification. Presence of furcation canals, position of lateral canals, intercanal communications, level of bifurcation, and convergence of the root canal system were recorded. M1 showed three roots in 4.1% of the sample. Commonest root canal morphology of the mesial root was type IV and the distal root was type I. The level of bifurcation of the root canals was commonly observed in the cervical one-third of the root while convergence was observed in the apical one-third in both roots. Prevalence of three rooted mandibular first molars is less than 5%. Mesial root showed the most variable canal morphology. Prevalence of furcation canals was 1.5% while that of middle mesial canals was 0.2%.

  3. Newer Root Canal Irrigants in Horizon: A Review

    Directory of Open Access Journals (Sweden)

    Sushma Jaju

    2011-01-01

    Full Text Available Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

  4. Rooting out Defense Mechanisms in Wheat against Plant Parasitic Nematodes

    Science.gov (United States)

    Root-lesion nematodes (Pratylenchus spp.) are soil borne pathogens of many important agricultural crops including wheat. Pratylenchus invade root cells and feed using a stylet, resulting in cell death. Common signs of Pratylenchus damage are root lesions, girdling, and lack of lateral branching. ...

  5. Association mapping in sunflower for sclerotinia head rot resistance

    Directory of Open Access Journals (Sweden)

    Fusari Corina M

    2012-06-01

    Full Text Available Abstract Background Sclerotinia Head Rot (SHR is one of the most damaging diseases of sunflower in Europe, Argentina, and USA, causing average yield reductions of 10 to 20 %, but leading to total production loss under favorable environmental conditions for the pathogen. Association Mapping (AM is a promising choice for Quantitative Trait Locus (QTL mapping, as it detects relationships between phenotypic variation and gene polymorphisms in existing germplasm without development of mapping populations. This article reports the identification of QTL for resistance to SHR based on candidate gene AM. Results A collection of 94 sunflower inbred lines were tested for SHR under field conditions using assisted inoculation with the fungal pathogen Sclerotinia sclerotiorum. Given that no biological mechanisms or biochemical pathways have been clearly identified for SHR, 43 candidate genes were selected based on previous transcript profiling studies in sunflower and Brassica napus infected with S. sclerotiorum. Associations among SHR incidence and haplotype polymorphisms in 16 candidate genes were tested using Mixed Linear Models (MLM that account for population structure and kinship relationships. This approach allowed detection of a significant association between the candidate gene HaRIC_B and SHR incidence (P  Conclusions These results suggest that AM will be useful in dissecting other complex traits in sunflower, thus providing a valuable tool to assist in crop breeding.

  6. Common Courses for Common Purposes:

    DEFF Research Database (Denmark)

    Schaub Jr, Gary John

    2014-01-01

    (PME)? I suggest three alternative paths that increased cooperation in PME at the level of the command and staff course could take: a Nordic Defence College, standardized national command and staff courses, and a core curriculum of common courses for common purposes. I conclude with a discussion of how...

  7. QCI Common

    Energy Technology Data Exchange (ETDEWEB)

    2016-11-18

    There are many common software patterns and utilities for the ORNL Quantum Computing Institute that can and should be shared across projects. Otherwise we find duplication of code which adds unwanted complexity. This is a software product seeks to alleviate this by providing common utilities such as object factories, graph data structures, parameter input mechanisms, etc., for other software products within the ORNL Quantum Computing Institute. This work enables pure basic research, has no export controlled utilities, and has no real commercial value.

  8. 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.

  9. Ultrastructural changes of compressed lumbar ventral nerve roots following decompression

    International Nuclear Information System (INIS)

    El-Barrany, Wagih G.; Hamdy, Raid M.; Al-Hayani, Abdulmonem A.; Jalalah, Sawsan M.; Al-Sayyad, Mohammad J.

    2006-01-01

    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)

  10. 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.

  11. Genetic analysis of partial resistance to basal stem rot (Sclerotinia sclerotiorum in sunflower

    Directory of Open Access Journals (Sweden)

    Amouzadeh Masoumeh

    2013-01-01

    Full Text Available Basal stem rot, caused by Sclerotinia sclerotiorum (Lib. de Bary, is one of the major diseases of sunflower (Helianthus annuus L. in the world. Quantitative trait loci (QTLs implicated in partial resistance to basal stem rot disease were identified using 99 recombinant inbred lines (RILs from the cross between sunflower parental lines PAC2 and RHA266. The study was undertaken in a completely randomized design with three replications under controlled conditions. The RILs and their parental lines were inoculated with a moderately aggressive isolate of S. sclerotiorum (SSKH41. Resistance to disease was evaluated by measuring the percentage of necrosis area three days after inoculation. QTLs were mapped using an updated high-density SSR and SNP linkage map. ANOVA showed significant differences among sunflower lines for resistance to basal stem rot (P≤0.05. The frequency distribution of lines for susceptibility to disease showed a continuous pattern. Composite interval mapping analysis revealed 5 QTLs for percentage of necrotic area, localized on linkage groups 1, 3, 8, 10 and 17. The sign of additive effect was positive in 5 QTLs, suggesting that the additive allele for partial resistance to basal stem rot came from the paternal line (RHA266. The phenotypic variance explained by QTLs (R2 ranged from 0.5 to 3.16%. Identified genes (HUCL02246_1, GST and POD, and SSR markers (ORS338, and SSL3 encompassing the QTLs for partial resistance to basal stem rot could be good candidates for marker assisted selection.

  12. Stem rots of oil palm caused by Ganoderma boninense: pathogen biology and epidemiology.

    Science.gov (United States)

    Pilotti, C A

    2005-01-01

    Oil palm (Elaeis guineensis Jacq.) has been grown in Papua New Guinea since the early 1960s. The most important disease of oil palm in PNG is a stem rot of the palm base. This is the same disease that constitutes a major threat to sustainable oil palm production in SE Asia. Investigations into the causal pathogen have revealed that the stem rots in PNG are caused predominantly by the basidiomycete Ganoderma boninense, with a minor pathogen identified as G. tornatum G. tornatum was found to have a broad host range whereas G. boninense appears to be restricted to palms. The population structure of G. boninense was investigated using inter-fertility studies between isolates collected from basal stem rots on oil palm. Although the G. boninense field populations are predominantly comprised of distinct individuals, a number of isolates were found that share single mating alleles. This indicates that out-crossing had occurred over several generations in the resident or wild population of G. boninense prior to colonization of oil palm. No direct hereditary relationship between isolates on neighbouring diseased palms was found, although an indirect link between isolates causing upper stem rot and basal stem rot was detected.

  13. Variation in oxalate and oxalate decarboxylase production by six species of brown and white rot fungi

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Oliver, Jason; Howell, Caitlin

      Oxalic acid (C2O4H2), the strongest of the organic acids is produced by both brown and white rot decay fungi and has been connected to various aspects of brown- and white rot decay including the Fenton reaction (Green and Highley, 1997; Munir et al.,2001). Oxalic acid is secreted into the wood...... cell lumen where it quickly dissociates into hydrogen ions and oxalate, resulting in a pH decrease of the environment, and oxalate-cation complexes. Generally, brown rot fungi accumulate larger quantities of oxalic acid in the wood than white rot fungi. The amount of oxalic acid has been shown to vary...... of formic acid and CO2 (Makela et al., 2002). So far only a few species of brown rot fungi have been shown to accumulate this enzyme (Micales, 1995, Howell and Jellison, 2006).   The purpose of this study was to investigate the variation in the levels of soluble oxalate and total oxalate, in correlation...

  14. Comparative transcriptome profiling of the early infection of wheat roots by Gaeumannomyces graminis var. tritici.

    Directory of Open Access Journals (Sweden)

    Lirong Yang

    Full Text Available Take-all, which is caused by the fungal pathogen, Gaeumannomyces graminis var. tritici (Ggt, is an important soil-borne root rot disease of wheat occurring worldwide. However, the genetic basis of Ggt pathogenicity remains unclear. In this study, transcriptome sequencing for Ggt in axenic culture and Ggt-infected wheat roots was performed using Illumina paired-end sequencing. Approximately 2.62 and 7.76 Gb of clean reads were obtained, and 87% and 63% of the total reads were mapped to the Ggt genome for RNA extracted from Ggt in culture and infected roots, respectively. A total of 3,258 differentially expressed genes (DEGs were identified with 2,107 (65% being 2-fold up-regulated and 1,151 (35% being 2-fold down-regulated between Ggt in culture and Ggt in infected wheat roots. Annotation of these DEGs revealed that many were associated with possible Ggt pathogenicity factors, such as genes for guanine nucleotide-binding protein alpha-2 subunit, cellulase, pectinase, xylanase, glucosidase, aspartic protease and gentisate 1, 2-dioxygenase. Twelve DEGs were analyzed for expression by qRT-PCR, and could be generally divided into those with high expression only early in infection, only late in infection and those that gradually increasing expression over time as root rot developed. This indicates that these possible pathogenicity factors may play roles during different stages of the interaction, such as signaling, plant cell wall degradation and responses to plant defense compounds. This is the first study to compare the transcriptomes of Ggt growing saprophytically in axenic cultures to it growing parasitically in infected wheat roots. As a result, new candidate pathogenicity factors have been identified, which can be further examined by gene knock-outs and other methods to assess their true role in the ability of Ggt to infect roots.

  15. Biomechanical aspects of external root resorption in orthodontic therapy

    OpenAIRE

    Abuabara, Allan

    2007-01-01

    External apical root resorption is a common phenomenon associated with orthodontic treatment. The factors relevant to root resorption can be divided into biological and mechanical factors. Some mechanical and biological factors might be associated with an increased or decreased risk of root resorption during orthodontic treatment. For mechanical factors, the extensive tooth movement, root torque and intrusive forces, movement type, orthodontic force magnitude, duration and type of force a...

  16. Why rooting fails

    OpenAIRE

    Creutz, Michael

    2007-01-01

    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.

  17. Detection, identification and differentiation of Pectobacterium and Dickeya species causing potato blackleg and tuber soft rot: a review

    NARCIS (Netherlands)

    Czajkowski, R.L.; Pérombelon, M.C.M.; Jafra, S.; Lojkowska, E.; Potrykus, M.; Wolf, van der J.M.; Sledz, W.

    2015-01-01

    The soft rot Enterobacteriaceae (SRE) Pectobacterium and Dickeya species (formerly classified as pectinolytic Erwinia spp.) cause important diseases on potato and other arable and horticultural crops. They may affect the growing potato plant causing blackleg and are responsible for tuber soft rot in

  18. Mucor rot - An emerging postharvest disease of mandarin fruit caused by Mucor piriformis and other Mucor spp. in California

    Science.gov (United States)

    In recent years, an emerging, undescribed postharvest fruit rot disease was observed on mandarin fruit after extended storage in California. We collected decayed mandarin fruit from three citrus packinghouses in the Central Valley of California in 2015 and identified this disease as Mucor rot caused...

  19. 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...

  20. Effect of combinations of gamma irradiation, hot water, Sodium chloride, and Acetic acid treatments on potato-dry rot

    International Nuclear Information System (INIS)

    El-Zayat, M.M.; Farahat, A.A.; Saad, N.H.; Shaarawy, N.S.M.

    1992-01-01

    Gamma irradiation increased the severity of dry rot in potato tubers when they were inoculated with any of 4 species of Fusarium, previously isolated either from irradiated or unirradiated tubers. Treating either irradiated or unirradiated tubers with warm water or sodium chloride solutions following inoculation with F. roseum also increased the severity of dry rot to some extent

  1. Rooting gene trees without outgroups: EP rooting.

    Science.gov (United States)

    Sinsheimer, Janet S; Little, Roderick J A; Lake, James A

    2012-01-01

    Gene sequences are routinely used to determine the topologies of unrooted phylogenetic trees, but many of the most important questions in evolution require knowing both the topologies and the roots of trees. However, general algorithms for calculating rooted trees from gene and genomic sequences in the absence of gene paralogs are few. Using the principles of evolutionary parsimony (EP) (Lake JA. 1987a. A rate-independent technique for analysis of nucleic acid sequences: evolutionary parsimony. Mol Biol Evol. 4:167-181) and its extensions (Cavender, J. 1989. Mechanized derivation of linear invariants. Mol Biol Evol. 6:301-316; Nguyen T, Speed TP. 1992. A derivation of all linear invariants for a nonbalanced transversion model. J Mol Evol. 35:60-76), we explicitly enumerate all linear invariants that solely contain rooting information and derive algorithms for rooting gene trees directly from gene and genomic sequences. These new EP linear rooting invariants allow one to determine rooted trees, even in the complete absence of outgroups and gene paralogs. EP rooting invariants are explicitly derived for three taxon trees, and rules for their extension to four or more taxa are provided. The method is demonstrated using 18S ribosomal DNA to illustrate how the new animal phylogeny (Aguinaldo AMA et al. 1997. Evidence for a clade of nematodes, arthropods, and other moulting animals. Nature 387:489-493; Lake JA. 1990. Origin of the metazoa. Proc Natl Acad Sci USA 87:763-766) may be rooted directly from sequences, even when they are short and paralogs are unavailable. These results are consistent with the current root (Philippe H et al. 2011. Acoelomorph flatworms are deuterostomes related to Xenoturbella. Nature 470:255-260).

  2. Creative Commons

    DEFF Research Database (Denmark)

    Jensen, Lone

    2006-01-01

    En Creative Commons licens giver en forfatter mulighed for at udbyde sit værk i en alternativ licensløsning, som befinder sig på forskellige trin på en skala mellem yderpunkterne "All rights reserved" og "No rights reserved". Derved opnås licensen "Some rights reserved"......En Creative Commons licens giver en forfatter mulighed for at udbyde sit værk i en alternativ licensløsning, som befinder sig på forskellige trin på en skala mellem yderpunkterne "All rights reserved" og "No rights reserved". Derved opnås licensen "Some rights reserved"...

  3. Science commons

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    SCP: Creative Commons licensing for open access publishing, Open Access Law journal-author agreements for converting journals to open access, and the Scholar's Copyright Addendum Engine for retaining rights to self-archive in meaningful formats and locations for future re-use. More than 250 science and technology journals already publish under Creative Commons licensing while 35 law journals utilize the Open Access Law agreements. The Addendum Engine is a new tool created in partnership with SPARC and U.S. universities. View John Wilbanks's biography

  4. Molecular Basis of Resistance to Fusarium Ear Rot in Maize

    Directory of Open Access Journals (Sweden)

    Alessandra Lanubile

    2017-10-01

    Full Text Available The impact of climate change has been identified as an emerging issue for food security and safety, and the increased incidence of mycotoxin contamination in maize over the last two decades is considered a potential emerging hazard. Disease control by chemical and agronomic approaches is often ineffective and increases the cost of production; for this reason the exploitation of genetic resistance is the most sustainable method for reducing contamination. The review focuses on the significant advances that have been made in the development of transcriptomic, genetic and genomic information for maize, Fusarium verticillioides molds, and their interactions, over recent years. Findings from transcriptomic studies have been used to outline a specific model for the intracellular signaling cascade occurring in maize cells against F. verticillioides infection. Several recognition receptors, such as receptor-like kinases and R genes, are involved in pathogen perception, and trigger down-stream signaling networks mediated by mitogen-associated protein kinases. These signals could be orchestrated primarily by hormones, including salicylic acid, auxin, abscisic acid, ethylene, and jasmonic acid, in association with calcium signaling, targeting multiple transcription factors that in turn promote the down-stream activation of defensive response genes, such as those related to detoxification processes, phenylpropanoid, and oxylipin metabolic pathways. At the genetic and genomic levels, several quantitative trait loci (QTL and single-nucleotide polymorphism markers for resistance to Fusarium ear rot deriving from QTL mapping and genome-wide association studies are described, indicating the complexity of this polygenic trait. All these findings will contribute to identifying candidate genes for resistance and to applying genomic technologies for selecting resistant maize genotypes and speeding up a strategy of breeding to contrast disease, through plants

  5. The common operational picture as collective sensemaking

    NARCIS (Netherlands)

    Wolbers, J.J.; Boersma, F.K.

    2013-01-01

    The common operational picture is used to overcome coordination and information management problems during emergency response. Increasingly, this approach is incorporated in more advanced information systems. This is rooted in an 'information warehouse' perspective, which implies information can be

  6. An overview of management of root fractures.

    Science.gov (United States)

    Prithviraj, D R; Bhalla, H K; Vashisht, R; Regish, K M; Suresh, P

    2014-01-01

    Crown or root fractures are the most commonly encountered emergencies in the dental clinic. Root fractures occur in fewer than eight percent of the traumatic injuries to permanent teeth. They are broadly classified as horizontal and vertical root fractures. Correct diagnosis of root fractures is essential to ensure a proper treatment plan and hence, the best possible prognosis. Indication of the type of treatment to be used depends primarily on the level of the fracture line. Therefore, a clinician must also have a thorough knowledge of the various treatment approaches to devise a treatment plan accordingly. Various treatment strategies have been proposed, each with their own advantages and disadvantages. Hence, this literature review presents an overview of the various types of root fractures and their management.

  7. Long-term control of root growth

    Science.gov (United States)

    Burton, Frederick G.; Cataldo, Dominic A.; Cline, John F.; Skiens, W. Eugene

    1992-05-26

    A method and system for long-term control of root growth without killing the plants bearing those roots involves incorporating a 2,6-dinitroaniline in a polymer and disposing the polymer in an area in which root control is desired. This results in controlled release of the substituted aniline herbicide over a period of many years. Herbicides of this class have the property of preventing root elongation without translocating into other parts of the plant. The herbicide may be encapsulated in the polymer or mixed with it. The polymer-herbicide mixture may be formed into pellets, sheets, pipe gaskets, pipes for carrying water, or various other forms. The invention may be applied to other protection of buried hazardous wastes, protection of underground pipes, prevention of root intrusion beneath slabs, the dwarfing of trees or shrubs and other applications. The preferred herbicide is 4-difluoromethyl-N,N-dipropyl-2,6-dinitro-aniline, commonly known as trifluralin.

  8. Efficacy of gaseous ozone to counteract postharvest table grape sour rot.

    Science.gov (United States)

    Pinto, L; Caputo, L; Quintieri, L; de Candia, S; Baruzzi, F

    2017-09-01

    This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m -3 ) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Common approach to common interests

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-06-01

    In referring to issues confronting the energy field in this region and options to be exercised in the future, I would like to mention the fundamental condition of the utmost importance. That can be summed up as follows: any subject in energy area can never be solved by one country alone, given the geographical and geopolitical characteristics intrinsically possessed by energy. So, a regional approach is needed and it is especially necessary for the main players in the region to jointly address problems common to them. Though it may be a matter to be pursued in the distant future, I am personally dreaming a 'Common Energy Market for Northeast Asia,' in which member countries' interests are adjusted so that the market can be integrated and the region can become a most economically efficient market, thus formulating an effective power to encounter the outside. It should be noted that Europe needed forty years to integrate its market as the unified common market. It is necessary for us to follow a number of steps over the period to eventually materialize our common market concept, too. Now is the time for us to take a first step to lay the foundation for our descendants to enjoy prosperity from such a common market.

  10. Host Specialization in the Charcoal Rot Fungus, Macrophomina phaseolina.

    Science.gov (United States)

    Su, G; Suh, S O; Schneider, R W; Russin, J S

    2001-02-01

    ABSTRACT To investigate host specialization in Macrophomina phaseolina, the fungus was isolated from soybean, corn, sorghum, and cotton root tissue and soil from fields cropped continuously to these species for 15 years in St. Joseph, LA. Chlorate phenotype of each isolate was determined after growing on a minimal medium containing 120 mM potassium chlorate. Consistent differences in chlorate sensitivity were detected among isolates from different hosts and from soil versus root. To further explore genetic differentiation among fungal isolates from each host, these isolates were examined by restriction fragment length polymorphism and random amplified polymorphic DNA (RAPD) analysis. No variations were observed among isolates in restriction patterns of DNA fragments amplified by polymerase chain reaction covering the internal transcribed spacer region, 5.8S rRNA and part of 25S rRNA, suggesting that M. phaseolina constitutes a single species. Ten random primers were used to amplify the total DNA of 45 isolates, and banding patterns resulting from RAPD analysis were compared with the neighbor-joining method. Isolates from a given host were genetically similar to each other but distinctly different from those from other hosts. Chlorate-sensitive isolates were distinct from chlorate-resistant isolates within a given host. In greenhouse tests, soybean, sorghum, corn, and cotton were grown separately in soil infested with individual isolates of M. phaseolina that were chosen based on their host of origin and chlorate phenotype. Root colonization and plant weight were measured after harvesting. More colonization of corn roots occurred when corn was grown in soil containing corn isolates compared with isolates from other hosts. However, there was no host specialization in isolates from soybean, sorghum, or cotton. More root colonization in soybean occurred with chlorate-sensitive than with chlorate-resistant isolates.

  11. Molecular mapping of QTLs for resistance to Gibberella ear rot, in corn, caused by Fusarium graminearum.

    Science.gov (United States)

    Ali, M Liakat; Taylor, Jeff H; Jie, Liu; Sun, Genlou; William, Manilal; Kasha, Ken J; Reid, Lana M; Pauls, K Peter

    2005-06-01

    Gibberella ear rot, caused by the fungus Fusarium graminearum Schwabe, is a serious disease of corn (Zea mays) grown in northern climates. Infected corn is lower yielding and contains toxins that are dangerous to livestock and humans. Resistance to ear rot in corn is quantitative, specific to the mode of fungal entry (silk channels or kernel wounds), and highly influenced by the environment. Evaluations of ear rot resistance are complex and subjective; and they need to be repeated over several years. All of these factors have hampered attempts to develop F. graminearum resistant corn varieties. The aim of this study was to identify molecular markers linked to the genes for resistance to Gibberella ear rot. A recombinant inbred (RI) population, produced from a cross between a Gibberella ear rot resistant line (CO387) and a susceptible line (CG62), was field-inoculated and scored for Gibberella ear rot symptoms in the F4, F6, and F7 generations. The distributions of disease scores were continuous, indicating that resistance is probably conditioned by multiple loci. A molecular linkage map, based on segregation in the F5 RI population, contained 162 markers distributed over 10 linkage groups and had a total length of 2237 cM with an average distance between markers of 13.8 cM. Composite interval mapping identified 11 quantitative trait loci (QTLs) for Gibberella ear rot resistance following silk inoculation and 18 QTLs following kernel inoculation in 4 environments that accounted for 6.7%-35% of the total phenotypic variation. Only 2 QTLs (on linkage group 7) were detected in more than 1 test for silk resistance, and only 1 QTL (on linkage group 5) was detected in more than 1 test for kernel resistance, confirming the strong influence of the environment on these traits. The majority of the favorable alleles were derived from the resistant parent (CO387). The germplasm and markers for QTLs with significant phenotypic effects may be useful for marker-assisted selection

  12. White-rot fungi in phenols, dyes and other xenobiotics treatment – a brief review

    Directory of Open Access Journals (Sweden)

    B. Zelić

    2010-01-01

    Full Text Available Bioremediation is an attractive technology that utilizes the metabolic potential of microorganisms in order to clean up the environmental pollutants to the less hazardous or non-hazardous forms with less input of chemicals, energy and time. White-rot fungi are unique organisms that show the capacities of degrading and mineralizing lignin as well as organic, highly toxic and recalcitrant compounds. The key enzymes of their metabolism are extracellular lignolytic enzymes that enable fungi to tolerate a relatively high concentration of toxic substrates. This paper gives a brief review of many aspects concerning the application of white-rot fungi with the purpose of the industrial contaminants removal.

  13. Evaluation of some garlic (Allium Sativum L.) mutants resistant to white rot disease by RAPD analysis

    International Nuclear Information System (INIS)

    Nabulsi, I.; Al-Safadi, B.; Mir ali, N.; Arabi, M.I.E.

    2002-01-01

    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)

  14. Effect of inoculation with arbuscular mycorrhizas on rooting, weaning and subsequent growth of micropropagated Malus (L. Moench

    Directory of Open Access Journals (Sweden)

    Marjatta Uosukainen

    1994-05-01

    Full Text Available The importance of different rooting methods and the effects of arbuscular mycorrhizal (AMF inoculation on the rooting rate, weaning survival and subsequent growth of microcuttings of Malus rootstock YP and the Finnish crab apple cultivars Hanna and Marjatta were studied in four experiments conducted at the Laukaa Research and Elite Plant Unit, Finland. Sucrose in the in vitro rooting medium gave the best support to weaning survival in comparision with glucose and fructose. Directly rooted microcuttings had a higher survival rate than in vitro rooted microcuttings. AMF inoculation did not improve the rooting rate in direct rooting. However, the Glomus hoi strain V98 caused severe rotting of microcuttings and thus lowered the rooting rate of cv. Hanna, AMF inoculation increased the mean shoot height of established plants, particularly inoculation with G. hoi V98, G. claroideum V43a or G. fistulosum V128. This effect, however, varied considerably in different host-fungus combinations. Some AMF strains, e.g. G. hoi V1O4, caused strong growth retardation. After the rooting and weaning stage, many uninoculated plants lapsed into arrest of growth. This phenomenon was less frequent in AMF inoculated plants. Optimal timing of AMF inoculation and nutritional level of rooting and weaning substrate are discussed.

  15. Induction and catabolite repression of cellulase and xylanase synthesis in the selected white-rot basidiomycetes

    Directory of Open Access Journals (Sweden)

    Aza Kobakhidze

    2016-09-01

    Full Text Available This paper reports regulation of endoglucanase (EC 3.2.1.4 and xylanase (EC 3.2.1.8 production in submerged cultivation of four white-rot basidiomycetes. Among carbon sources tested, the Avicel-based medium provided the highest levels of both hydrolases activities in all fungal cultures. However, the maximum endoglucanase and xylanase activities of the tested basidiomycetes varied from 3.9 U/ml and 7.4 U/ml in Fomes fomentarius to 34.2 U/ml and 29.5 U/ml in Pseudotrametes gibbosa, respectively (P. gibbosa specific cellulase and xylanase activities achieved 8.55 and 7.38 U/mg, respectively. Replacement of Avicel in the medium with carboxymethyl cellulose or xylan significantly lowered the enzyme yield of the tested fungi. Moreover, xylan did not ensure high xylanase activity of these fungi. Lignocellulosic substrates used as a carbon source provided poorer productivity (the specific CMCase activity was 1.12–3.62 U/mg and the specific xylanase activity was 1.95–3.32 U/mg. Expression of endoglucanase and xylanase synthesis in Panus lecometei and P. gibbosa was inducible; supplementation of the glycerol-containing medium with Avicel accompanied with a sharp increase of the fungal specific CMCase and xylanase activities from 0.02–0.04 U/mg to 1.30–8.55 U/mg. Supplementation of the Avicel-induced cultures with glucose or glycerol caused a catabolite repression of the cellulase and xylanase formation by P. gibbosa and P. lecometei. The enzyme synthesis resumed only after depletion of easily metabolizable carbon source, glucose or glycerol, from the medium. The data received suggest that in the tested fungi endoglucanase and xylanase synthesis is under control by a common regulatory mechanism.

  16. Identification and Differentiation of Monilinia Species Causing Brown Rot of Pome and Stone Fruit using High-Resolution Melting (HRM) Analysis.

    Science.gov (United States)

    Papavasileiou, Antonios; Madesis, Panagiotis B; Karaoglanidis, George S

    2016-09-01

    Brown rot is a devastating disease of stone fruit caused by Monilinia spp. Among these species, Monilinia fructicola is a quarantine pathogen in Europe but has recently been detected in several European countries. Identification of brown rot agents relies on morphological differences or use of molecular methods requiring fungal isolation. The current study was initiated to develop and validate a high-resolution melting (HRM) method for the identification of the Monilinia spp. and for the detection of M. fructicola among other brown rot pathogens. Based on the sequence of the cytb intron from M. laxa, M. fructicola, M. fructigena, M. mumecola, M. linhartiana, and M. yunnanensis isolates originating from several countries, a pair of universal primers for species identification and a pair of primers specific to M. fructicola were designed. The specificity of the primers was verified to ensure against cross-reaction with other fungal species. The melting curve analysis using the universal primers generated six different HRM curve profiles, each one specific for each species. Τhe HRM analysis primers specific to M. fructicola amplified a 120-bp region with a distinct melt profile corresponding to the presence of M. fructicola, regardless of the presence of other species. HRM analysis can be a useful tool for rapid identification and differentiation of the six Monilinia spp. using a single primer pair. This novel assay has the potential for simultaneous identification and differentiation of the closely related Monilinia spp. as well as for the differentiation of M. fructicola from other common pathogens or saprophytes that may occur on the diseased fruit.

  17. Making the Common Good Common

    Science.gov (United States)

    Chase, Barbara

    2011-01-01

    How are independent schools to be useful to the wider world? Beyond their common commitment to educate their students for meaningful lives in service of the greater good, can they educate a broader constituency and, thus, share their resources and skills more broadly? Their answers to this question will be shaped by their independence. Any…

  18. 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.

  19. Action of plant root exudates in bioremediations: a review

    Directory of Open Access Journals (Sweden)

    Peter Dundek

    2011-01-01

    Full Text Available This work presents a summary of literature dealing with the use of plant root exudates in bioremediations. Bioremediation using plants (phytoremediation or rhizoremediation and associate rhizosphere to decontaminate polluted soil is a method based on the catabolic potential of root-associated microorganisms, which are supported by the organic substrates released from roots. These substrates are called “root exudates”. Root exudates support metabolism of pollutants-decomposing microorganisms in the rhizosphere, and affect sorption / desorption of pollutants. Awareness of exudation rates is necessary for testing soil decontamination. Commonly, water-soluble root exudates of different plants are studied for their qualitative composition which should be related to total carbon of exuded water-soluble compounds. This paper presents the determined rate of plant root exudation and the amount of root exudates carbon used to form artificial rhizosphere.

  20. 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 ...

  1. Polycyclic aromatic hydrocarbon degradation by the white rot fungus Bjerkandera sp. strain BOS55

    NARCIS (Netherlands)

    Kotterman, M.

    1998-01-01

    Outline of this thesis
    In 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,

  2. Chemical and biological control of Sclerotinia stem rot in the soybean crop

    Directory of Open Access Journals (Sweden)

    Ciro Hideki Sumida

    2015-05-01

    Full Text Available It was evaluated the effect of fungicides and the microbial control agent Trichoderma harzianum on the inhibition of the carpogenic and ascospore germination of Sclerotinia sclerotiorum. This study also evaluated the chemical, fungicidal and microbial control of white mold or Sclerotinia stem rot of soybean in the field. Three experiments were conducted, as follows: 1 inhibition of carpogenic germination of sclerotia, 2 inhibition of ascospore germination, and 3 control of Sclerotinia stem rot in a soybean crop under field conditions. The treatments evaluated were fluazinam, procymidone, iprodione, thiophanate-methyl, carbendazim, benzalkonium chloride + fluazinam, and T. harzianum. Procymidone resulted in an inhibition of 13.5% and benzalkonium chloride in an inhibition of 13.9% in an ascospore germination test. Fluazinam and procymidone were the most effective in reducing the production of ascospores/apothecium, representing 65.6% and 82.4% of inhibition. Procymidone and fluazinam if combined or not with benzalkonium chloride were the most effective in controlling sclerotinia stem rot under field conditions when applied at the onset of flowering and 15 days later. In the 2009-10 harvest, these two fungicides reduced the incidence of Sclerotinia stem rot by 73.1 and 71.6% and in the 2010-11 harvest by 75.7 and 77.6%, respectively.

  3. Interaction between N-fertilizer and water availability on borer-rot complex in sugarcane

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo da Rocha Pannuti

    2015-03-01

    Full Text Available This study aimed to evaluate the effects of nitrogen availability in fertigation and rainfed management, as well as their interactions with the incidence of and damage caused by D. saccharalis and red rot in sugarcane. The experiment consisted of four treatments (0 and 150 kg ha–1 of N-fertilizer with irrigation; 0 and 150 kg ha–1 of N-fertilizer in rainfed management in a randomized complete block design with four replications. The evaluated parameters were the number of holes and internodes with red rot per meter of cultivation, stalk yield and sugar content. In the laboratory (T = 25 ± 2 °C; R.H. = 70 ± 10%: 12:12-L:D, we evaluated the attractiveness and consumption of fragments of stalks from the different treatments for fourth instar larvae through choice and no-choice tests in a randomized complete block design with ten replications. Nitrogen fertilization via irrigation has favorable effects on borer-rot complex and leads to higher gains in stalk and sugar yields when compared to rainfed management. The increments of stalk and sugar yields due to nitrogen fertilization compensates for the increase in borer-rot complex infestation. In laboratory tests, D. saccharalis larvae were similarly attracted to all treatments regardless of the doses of N-fertilizer or the water regimes evaluated. However, fragments of sugarcane stalks produced with nitrogen fertilization were consumed more by D. saccharalis in both water regimes.

  4. Differential stress-induced regulation of two quinone reductases in the brown rot Basidiomycete Gloeophyllum trabeum

    Science.gov (United States)

    Roni Cohen; Melissa R. Suzuki; Kenneth E. Hammel

    2004-01-01

    Quinone reductases (QRDs) have two important functions in the basidiomycete Gloeophyllum trabeum, which causes brown rot of wood. First, a QRD is required to generate biodegradative hydroxyl radicals via redox cycling between two G. trabeum extracellular metabolites, 2,5-dimethoxyhydroquinone (2,5-DMHQ) and 2,5-dimethoxy-1,4-benzoquinone (2,5- DMBQ). Second, because 2,...

  5. Characterisation of Alternaria species-groups associated with core rot of apples in South Africa

    DEFF Research Database (Denmark)

    Serdani, M.; Kang, J.C.; Andersen, Birgitte

    2002-01-01

    Alternaria core rot of red apple cultivars is a serious post-harvest disease in South Africa. Thirty isolates of Alternaria spp. previously isolated from apple, together with reference isolates of A. alternata and A. infectoria, were characterised and grouped according to their sporulation patter...

  6. Biochemical response and host-pathogen relation of stalk rot fungi ...

    African Journals Online (AJOL)

    Stalk rot is a destructive disease in maize caused by Fusarium and Macrophomina species. A study was carried out to understand the mode of infection, host biochemical response and comparison of inoculation techniques in Fusarium verticillioides and Macrophomina phaseolina in maize. In seed inoculation experiment, ...

  7. Modification of wheat straw lignin by solid state fermentation with white-rot fungi

    NARCIS (Netherlands)

    Dinis, M.J.; Bezerra, R.M.F.; Nunes, F.; Dias, A.A.; Guedes, C.; Ferreira, L.M.M.; Cone, J.W.; Marques, G.S.M.; Barros, A.R.N.; Rodrigues, M.A.M.

    2009-01-01

    The potential of crude enzyme extracts, obtained from solid state cultivation of four white-rot fungi (Trametes versicolor, Bjerkandera adusta, Ganoderma applanatum and Phlebia rufa), was exploited to modify wheat straw cell wall. At different fermentation times, manganese-dependent peroxidase

  8. Rapid polyether cleavage via extracellular one-electron oxidation by a brown-rot basidiomycete.

    Science.gov (United States)

    Kerem, Z; Bao, W; Hammel, K E

    1998-09-01

    Fungi that cause brown rot of wood are essential biomass recyclers and also the principal agents of decay in wooden structures, but the extracellular mechanisms by which they degrade lignocellulose remain unknown. To test the hypothesis that brown-rot fungi use extracellular free radical oxidants as biodegradative tools, Gloeophyllum trabeum was examined for its ability to depolymerize an environmentally recalcitrant polyether, poly(ethylene oxide) (PEO), that cannot penetrate cell membranes. Analyses of degraded PEOs by gel permeation chromatography showed that the fungus cleaved PEO rapidly by an endo route. 13C NMR analyses of unlabeled and perdeuterated PEOs recovered from G. trabeum cultures showed that a major route for depolymerization was oxidative C---C bond cleavage, a reaction diagnostic for hydrogen abstraction from a PEO methylene group by a radical oxidant. Fenton reagent (Fe(II)/H2O2) oxidized PEO by the same route in vitro and therefore might account for PEO biodegradation if it is produced by the fungus, but the data do not rule out involvement of less reactive radicals. The reactivity and extrahyphal location of this PEO-degrading system suggest that its natural function is to participate in the brown rot of wood and that it may enable brown-rot fungi to degrade recalcitrant organopollutants.

  9. Association of Verde plant bug, Creontiades signatus (Hemiptera: Miridae), with cotton boll rot

    Science.gov (United States)

    Cotton along the Gulf Coast of south Texas has experienced loss from cotton boll rot especially during the last 10 to 15 years, and stink bugs and plant bugs (Hemiptera: Pentatomidae and Miridae) that feed on cotton bolls have been suspected in introducing the disease. A replicated grower field surv...

  10. First report of frosty pod rot caused by Moniliophthora roreri on cacao in Bolivia

    Science.gov (United States)

    Frosty pod rot (FPR) is a devastating cacao disease caused by the basidiomycete Moniliophthora roreri (Aime and Phillips-Mora, 2005). The disease is confined to 13 countries in Central and South America and constitutes a permanent threat for cacao cultivation worldwide. In July 2012, FPR was detect...

  11. Evaluation of watermelon varieties for tolerance to powdery mildew and Phytophthora fruit rot, 2014

    Science.gov (United States)

    This experiment was conducted at the U.S. Vegetable Laboratory farm in Charleston, SC. The soil was Yonges loamy fine sand. This study was undertaken to determine the performance of seeded and seedless commercial watermelon varieties for tolerance to powdery mildew (PM) and Phytophthora fruit rot as...

  12. Biodiversity of Fusarium species causing ear rot of maize in Germany

    NARCIS (Netherlands)

    Görtz, A.; Oerke, E.C.; Steiner, U.; Waalwijk, C.; Vries, de P.M.; Dehne, H.W.

    2008-01-01

    In Germany, maize is one of the most important agriculture commodities, a major component in animal feed as well as an essential substrate producing biogas. Maize car rot poses a major impact worldwide as it is caused by several Fusarium spp., most of which have the ability to produce mycotoxins.

  13. First report of anthracnose fruit rot of blueberry caused by Colletotrichum fioriniae in New Jersey

    Science.gov (United States)

    Anthracnose fruit rot is the most important disease of blueberry in New Jersey. Most fungicide applications in New Jersey and other blueberry growing regions is for the control of this disease. The causal agent of this disease has been reported to be Colletotrichum acutatum and other species in the ...

  14. Biocontrol with Trichoderma species for the management of postharvest crown rot of banana

    Directory of Open Access Journals (Sweden)

    G. Sangeetha

    2009-09-01

    Full Text Available Lasiodiplodia theobromae and Colletotrichum musae cause the postharvest crown rot disease complex of banana. In vitro experiments evaluated the effect of twelve isolates of Trichoderma spp. from the soil of organic banana orchards (‘native isolates’ and eight isolates of Trichoderma spp. from culture collections (‘introduced isolates’ on the two pathogens. The native and introduced Trichoderma spp. had varied antagonistic effects against the two pathogens. Eight Trichoderma spp. isolates effective in the in vitro assays were evaluated singly on fruits both at room temperature and in cold storage. Single antagonists did not satisfactorily control crown rot on the fruits as compared with the fungicide carbendazim. However, two isolates of T. viride, one of T. harzianum and one of T. koningii performed well when applied singly, and these were selected for evaluation in isolate mixtures. There was very little antagonism between these isolates. Of 11 two-way, three-way and four-way mixtures of these isolates, the four-way and a three-way mixtures reduced crown rot incidence, both at room temperature and in cold storage, giving better control than carbendazim. The study identified consortia of compatible Trichoderma antagonists with superior biocontrol potential for the management of the postharvest crown rot complex of banana.

  15. Lignin degrading system of white-rot fungi and its exploitation for dye decolorization

    Czech Academy of Sciences Publication Activity Database

    Shah, V.; Nerud, František

    2002-01-01

    Roč. 48, - (2002), s. 857-870 ISSN 0008-4166 R&D Projects: GA ČR GA526/01/0915 Institutional research plan: CEZ:AV0Z5020903 Keywords : lignin degradation * white-rot fungi * laccase Subject RIV: EE - Microbiology, Virology Impact factor: 1.080, year: 2002

  16. Irpex lacteus, a white-rot fungus with biotechnological potential — review

    Czech Academy of Sciences Publication Activity Database

    Novotný, Čeněk; Cajthaml, Tomáš; Svobodová, Kateřina; Šušla, Martin; Šašek, Václav

    2009-01-01

    Roč. 5, č. 5 (2009), s. 375-390 ISSN 0015-5632 R&D Projects: GA AV ČR IAAX00200901 Institutional research plan: CEZ:AV0Z50200510 Keywords : White-rot fungi * degradation * irpex lacteus Subject RIV: EE - Microbiology, Virology Impact factor: 0.978, year: 2009

  17. FOOT ROT DISEASE IDENTIFICATION FOR VELLAIKODI VARIETY OF BETELVINE PLANTS USING DIGITAL IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    J. Vijayakumar

    2012-11-01

    Full Text Available Betelvine plants are infected variety of diseases in the complete plantation without any premature warning of the diseases. The aim of this paper is to detection of foot rot disease in the vellaikodi variety of betelvine plants using digital image processing techniques. The digital images of the uninfected or normal betelvine leaves and the digital images of the infected in foot rot diseased betelvine leaves at different stages are collected from different Betelvine plants using a high resolution digital camera and collected betelvine images are stored with JPEG format. The digital images of the betelvine leaves analyses are done using the image processing toolbox in MATLAB which gives the normal patterns of the digital images. Using RGB encoding process, the RGB components of the betelvine leaves are separated. The mean and median values for all sample leaves are computed and calculated values are stored in the system. The mean and median values of test leaves are computed and compared with the stored values. As the result of this comparison, it is identified whether test leaves are affected by foot rot disease or not. Finally this analysis helps to recognize the foot rot disease can be identified before it spreads to entire crop.

  18. 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...

  19. Status of maize stalk rot complex in western belts of Nepal and its integrated management

    Directory of Open Access Journals (Sweden)

    Subash Subedi

    2016-12-01

    Full Text Available Maize stalk rot complex is becoming a serious threat for maize growing areas of Nepal. A field monitoring for maize stalk rot complex was done during crop season (August, 2016 covering 10 farmers field each of Surkhet, Banke, Dang, Chitwan and Nawalparasi districts. Maize crop showed highly susceptible reaction to the disease at western belts of Dang and susceptible reaction was marked in Chitwan and Nawalparasi districts while the disease effect was mild at Banke and Surkhet district. Most of the plant diseases managed successfully through the application of bio-control agents, host resistance, chemicals and other different cultural control methods. The result of field experiment conducted at Dang showed that all the treatments had significant (P≤0.05 effect on percent disease index (PDI and crop yield over farmers practice to control maize stalk rot. The higher percent disease control (52.36% and yield increase (40.29% were recorded from the plot sprayed with streptocyclin @ 2 g L-1 and insecticide (cypermethrin + chloropyrifos @ 2.5 ml L-1 of water during knee height and subsequent spray after 15 days interval as compared to farmers practice. Out of 30 genotypes, Rampur composit, Arun 2, Rampur 34, RamS03F08, TLBRS07F16 and Rampur 24 were found resistant against stalk rot complex with higher yield at Rampur Chitwan.

  20. Rhizoctonia solani as a component in the bottom rot complex of glasshouse lettuce

    NARCIS (Netherlands)

    Kooistra, T.

    1983-01-01

    The basal parts of maturing glasshouse lettuce can be attacked by several soil fungi, which cause bottom rot. Until recently quintozene was generally applied against this disease complex. The study of the causal fungi - especially Rhizoctonia solani - and their control was

  1. Effect of bunch rot on the sensory characteristics of the Gewürztraminer wine

    Directory of Open Access Journals (Sweden)

    Julio Meneguzzo

    2008-06-01

    Significance and impact of the study: In viticultural regions characterized by rainy and hot summers many pathogens have appropriate conditions to develop. In this way, to make quality wines it is very important to control grape rot diseases in the vineyards and to avoid grapes infected with pathogens related to these diseases during vinification.

  2. Isolation and identification of bacteria causing blackleg and soft rot of potato

    Science.gov (United States)

    Both Dickeya and Pectobacterium spp. are important causal agents of blackleg and soft rot of potato. To understand the outbreak of blackleg in the Northeastern U.S. in 2015, samples were collected from symptomatic plants, dormant tubers, and surface water in 2016 and 2017. Diseased plant samples wer...

  3. Genetic Architecture of Charcoal Rot (Macrophomina phaseolina) Resistance in Soybean Revealed Using a Diverse Panel

    Science.gov (United States)

    Charcoal rot disease caused by Macrophomina phaseolina is responsible for significant yield losses in soybean production. Among the methodologies available for controlling this disease, breeding for resistance is the most promising. Progress in breeding efforts has been slow due to the insufficient ...

  4. Draft genome sequence of the white-rot fungus Obba rivulosa 3A-2

    Science.gov (United States)

    Otto Miettinen; Robert Riley; Kerrie Barry; Daniel Cullen; Ronald P. de Vries; Matthieu Hainaut; Annele Hatakka; Bernard Henrissat; Kristiina Hilden; Rita Kuo; Kurt LaButti; Anna Lipzen; Miia R. Makela; Laura Sandor; Joseph W. Spatafora; Igor V. Grigoriev; David S. Hibbett

    2016-01-01

    We report here the first genome sequence of the white-rot fungus Obba rivulsa (Polyporales, Basidiomycota), a polypore known for its lignin-decomposing ability. The genome is based on the homokaryon 3A-2 originating in Finland. The genome is typical in size and carbohydrate active enzyme (CAZy) content for wood-decomposing basidiomycetes.

  5. Draft genome sequence of a monokaryotic model brown-rot fungus Postia (Rhodonia) placenta SB12

    Science.gov (United States)

    Jill Gaskell; Phil Kersten; Luis F. Larrondo; Paulo Canessa; Diego Martinez; David Hibbett; Monika Schmoll; Christian P. Kubicek; Angel T. Martinez; Jagjit Yadav; Emma Master; Jon Karl Magnuson; Debbie Yaver; Randy Berka; Kathleen Lail; Cindy Chen; Kurt LaButti; Matt Nolan; Anna Lipzen; Andrea Aerts; Robert Riley; Kerrie Barry; Bernard Henrissat; Robert Blanchette; Igor V. Grigoriev; Dan Cullen

    2017-01-01

    We report the genome of Postia (Rhodonia) placenta MAD-SB12, a homokaryotic wood decay fungus (Basidiomycota, Polyporales). Intensively studied as a representative brown rot decayer, the gene complement is consistent with the rapid depolymerization of cellulose but not lignin.

  6. Filamentous fungi associated with natural infection of noble rot on withered grapes.

    Science.gov (United States)

    Lorenzini, M; Simonato, B; Favati, F; Bernardi, P; Sbarbati, A; Zapparoli, G

    2018-05-02

    The effects of noble rot infection of grapes on the characteristics of different types of wine, including Italian passito wine, are well known. Nevertheless, there is still little information on filamentous fungi associated with noble-rotten grapes. In this study, withered Garganega grapes for passito wine production, naturally infected by noble rot, were analyzed and compared to sound grapes. Skin morphology and fungal population on berry surfaces were analyzed. Scanning electron microscopy analysis revealed microcracks, germination conidia and branched hyphae on noble-rotten berries. Penicillium, Aureobasidium and Cladosporium were the most frequent genera present. Analysis of single berries displayed higher heterogeneity of epiphytic fungi in those infected by noble-rot than in sound berries. Penicillium adametzoides, Cladosporium cladospoirioides and Coniochaeta polymorpha were recovered. These, to the best of our knowledge, had never been previously isolated from withered grapes and, for C. polymorpha, from grapevine. This study provided novel data on noble rot mycobiota and suggests that fungi that co-habit with B. cinerea could have an important role on grape and wine quality. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Molecular phylogeny of Laetiporus and other brown rot polypore genera in North America

    Science.gov (United States)

    Daniel L. Lindner; Mark T. Banik

    2008-01-01

    Phylogenetic relationships were investigated among North American species of Laetiporus, Leptoporus, Phaeolus, Pycnoporellus, and Wolfiporia using ITS, nuclear large subunit and mitochondrial small subunit rDNA sequences. Members of these genera have poroid hymenophores, simple septate hyphae and cause brown rots in a variety of...

  8. 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.

  9. Chemical Eradication of the Ring Rot Bacterium Clavibacter michiganensis subsp. sepedonicus on Potato Storage Crates

    NARCIS (Netherlands)

    Stevens, L.H.; Lamers, J.G.; Zouwen, van der P.S.; Mendes, O.; Berg, van den W.; Tjou-Tam-Sin, N.N.A.; Jilesen, C.J.T.J.; Spoorenberg, P.M.; Wolf, van der J.M.

    2017-01-01

    Four commercially available disinfection products were tested for their efficacy against Clavibacter michiganensis subsp. sepedonicus (Cms), causative agent of bacterial ring rot, on wooden potato storage crates. Each of these products represented a different class of biocide, i.e. organic acids

  10. [Calcitonin as an alternative treatment for root resorption].

    Science.gov (United States)

    Pierce, A; Berg, J O; Lindskog, S

    1989-01-01

    Inflammatory root resorption is a common finding following trauma and will cause eventual destruction of the tooth root if left untreated. This study examined the effects of intrapulpal application of calcitonin, a hormone known to inhibit osteoclastic bone resorption, on experimental inflammatory root resorption induced in monkeys. Results were histologically evaluated using a morphometric technique and revealed that calcitonin was an effective medicament for the treatment of inflammatory root resorption. It was concluded that this hormone could be a useful therapeutic adjunct in difficult cases of external root resorption.

  11. Endoscopic root canal treatment.

    Science.gov (United States)

    Moshonov, Joshua; Michaeli, Eli; Nahlieli, Oded

    2009-10-01

    To describe an innovative endoscopic technique for root canal treatment. Root canal treatment was performed on 12 patients (15 teeth), using a newly developed endoscope (Sialotechnology), which combines an endoscope, irrigation, and a surgical microinstrument channel. Endoscopic root canal treatment of all 15 teeth was successful with complete resolution of all symptoms (6-month follow-up). The novel endoscope used in this study accurately identified all microstructures and simplified root canal treatment. The endoscope may be considered for use not only for preoperative observation and diagnosis but also for active endodontic treatment.

  12. Benefits of flooding-induced aquatic adventitious roots depend on the duration of submergence: linking plant performance to root functioning.

    Science.gov (United States)

    Zhang, Qian; Huber, Heidrun; Beljaars, Simone J M; Birnbaum, Diana; de Best, Sander; de Kroon, Hans; Visser, Eric J W

    2017-07-01

    Temporal flooding is a common environmental stress for terrestrial plants. Aquatic adventitious roots (aquatic roots) are commonly formed in flooding-tolerant plant species and are generally assumed to be beneficial for plant growth by supporting water and nutrient uptake during partial flooding. However, the actual contribution of these roots to plant performance under flooding has hardly been quantified. As the investment into aquatic root development in terms of carbohydrates may be costly, these costs may - depending on the specific environmental conditions - offset the beneficial effects of aquatic roots. This study tested the hypothesis that the balance between potential costs and benefits depends on the duration of flooding, as the benefits are expected to outweigh the costs in long-term but not in short-term flooding. The contribution of aquatic roots to plant performance was tested in Solanum dulcamara during 1-4 weeks of partial submergence and by experimentally manipulating root production. Nutrient uptake by aquatic roots, transpiration and photosynthesis were measured in plants differing in aquatic root development to assess the specific function of these roots. As predicted, flooded plants benefited from the presence of aquatic roots. The results showed that this was probably due to the contribution of roots to resource uptake. However, these beneficial effects were only present in long-term but not in short-term flooding. This relationship could be explained by the correlation between nutrient uptake and the flooding duration-dependent size of the aquatic root system. The results indicate that aquatic root formation is likely to be selected for in habitats characterized by long-term flooding. This study also revealed only limited costs associated with adventitious root formation, which may explain the maintenance of the ability to produce aquatic roots in habitats characterized by very rare or short flooding events. © The Author 2017. Published by

  13. Phylogenetic patterns of tragedy of commons in intraspecific root competition

    Czech Academy of Sciences Publication Activity Database

    Smyčka, J.; Herben, Tomáš

    2017-01-01

    Roč. 417, 1-2 (2017), s. 87-97 ISSN 0032-079X R&D Projects: GA ČR(CZ) GA16-19245S Institutional support: RVO:67985939 Keywords : evolutionary game theory * self/non-self-recognition * phenotypic plasticity Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 3.052, year: 2016

  14. Occurrence, characterization and management of fruit rot of immature cucumber fruits under arid greenhouse conditions

    Directory of Open Access Journals (Sweden)

    ABDULLAH M AL-SADI

    2012-01-01

    Full Text Available A study was undertaken to characterize and manage pathogens associated with fruit rot of immature cucumber fruits in greenhouses in Oman. A survey over 5 growing seasons from 2008 to 2010 in 99 different greenhouses in Oman showed that the disease is prevalent in 91 (92% greenhouses and results in losses of 10 to 60% (avg. 33% of immature fruits per plant. Incidence of the disease was not found to be affected by growing seasons, which could be attributed to the limited fluctuations in ambient temperatures in greenhouses. Isolations from diseased cucumber fruits yielded Alternaria alternata (isolation frequency = 52%, Fusarium equiseti (40%, Cladosporium tenuissium (27%, Botrytis cinerea (6%, Fusarium solani (6%, Corynespora cassiicola (3%, Aspergillus spp. (2%, Curvularia sp. (1% and Bipolaris sp. (1%. With the exception of Curvularia and Bipolaris species, all other fungi were pathogenic on cucumber fruits, with Fusarium equiseti being the most aggressive, followed by Corynespora cassiicola, Botrytis cinerea and Alternaria alternata. Cladosporium and Aspergillus spp. were found to be weakly pathogenic. Comparing the efficacy of foliar and soil applications of carbendazim fungicide on fruit rot of cucumber showed that foliar applications significantly reduced fruit rot and increased cucumber yield when compared to soil application or to control (P < 0.01. This appears to be the first report of the association of Corynespora cassiicola and Fusarium equiseti with fruit rot of immature greenhouse cucumbers. This is also the first report in Oman for the association of Cladosporium tenuissimum with fruit rot of immature cucumbers. Findings are discussed in terms of factors affecting disease control in greenhouses using carbendazim.

  15. Effects of bunch rot (Botrytis cinerea) and powdery mildew (Erysiphe necator) fungal diseases on wine aroma

    Science.gov (United States)

    Lopez Pinar, Angela; Rauhut, Doris; Ruehl, Ernst; Buettner, Andrea

    2017-03-01

    This study aimed to characterize the effects of bunch rot and powdery mildew on the primary quality parameter of wine, the aroma. The influence of these fungal diseases was studied by comparative Aroma Extract Dilution Analyses (AEDA) and sensory tests. The effect of bunch rot was investigated on three grape varieties, namely White Riesling, Red Riesling and Gewürztraminer and that of powdery mildew on the hybrid Gm 8622-3; thereby, samples were selected that showed pronounced cases of infection to elaborate potential currently unknown effects. Both infections revealed aromatic differences induced by these fungi. The sensory changes were not associated with one specific compound only, but were due to quantitative variations of diverse substances. Bunch rot predominantly induced an increase in the intensities of peach-like/fruity, floral and liquor-like/toasty aroma notes. These effects were found to be related to variations in aroma substance composition as monitored via AEDA, mainly an increase in the FD factors of lactones and a general moderate increase of esters and alcohols. On the other hand, powdery mildew decreased the vanilla-like character of the wine while the remaining sensory attributes were rather unaffected. Correspondingly, FD factors of the main aroma constituents were either the same or only slightly modified by this disease. Moreover, bunch rot influenced the aroma profiles of the three varieties studied to a different degree. In hedonic evaluation, bunch rot-affected samples were rated as being more pleasant in comparison to their healthy controls in all three varieties while the powdery mildew-affected sample was rated as being less pleasant than its healthy control.

  16. Scholarly context not found: one in five articles suffers from reference rot.

    Directory of Open Access Journals (Sweden)

    Martin Klein

    Full Text Available The emergence of the web has fundamentally affected most aspects of information communication, including scholarly communication. The immediacy that characterizes publishing information to the web, as well as accessing it, allows for a dramatic increase in the speed of dissemination of scholarly knowledge. But, the transition from a paper-based to a web-based scholarly communication system also poses challenges. In this paper, we focus on reference rot, the combination of link rot and content drift to which references to web resources included in Science, Technology, and Medicine (STM articles are subject. We investigate the extent to which reference rot impacts the ability to revisit the web context that surrounds STM articles some time after their publication. We do so on the basis of a vast collection of articles from three corpora that span publication years 1997 to 2012. For over one million references to web resources extracted from over 3.5 million articles, we determine whether the HTTP URI is still responsive on the live web and whether web archives contain an archived snapshot representative of the state the referenced resource had at the time it was referenced. We observe that the fraction of articles containing references to web resources is growing steadily over time. We find one out of five STM articles suffering from reference rot, meaning it is impossible to revisit the web context that surrounds them some time after their publication. When only considering STM articles that contain references to web resources, this fraction increases to seven out of ten. We suggest that, in order to safeguard the long-term integrity of the web-based scholarly record, robust solutions to combat the reference rot problem are required. In conclusion, we provide a brief insight into the directions that are explored with this regard in the context of the Hiberlink project.

  17. The association of Tarsonemus mites (Acari: Heterostigmata) with different apple developmental stages and apple core rot diseases

    OpenAIRE

    Ueckermann, Edward Albert; Van der Walt, Lené; Spotts, Robert A.; Smit, Francois J.; Jensen, Tamaryn; McLeod, Adéle

    2011-01-01

    Information on the role of mites in the genus Tarsonemus Canestrini and Fanzago, 1876 in the epidemiology of apple core rots (wet and dry) is limited. The aims of this study were to (1) assess the effect of different apple developmental stages (buds, blossoms, 4-cm diameter fruit, mature fruit and mummies) on the relative abundance of Tasonemus mites, (2) determine if there is a tendency of Tarsonemus mites to be associated with wet core rot (WCR) and dry core rot (DCR) apples, and (3) evalua...

  18. Involvement of phenazines and biosurfactants in biocontrol of Pythium myriotylum root rot on cocoyam by Pseudomonas sp. CMR12A

    Science.gov (United States)

    Pseudomonas sp. CMR12a was isolated from the rhizosphere of the tropical tuber crop cocoyam and produces both phenazines and cyclic lipopeptide (CLP) biosurfactants. CMR12a was shown to be an efficient biocontrol agent of P. myriotylum on cocoyam. To assess the importance of phenazine and biosurfact...

  19. Irrational Square Roots

    Science.gov (United States)

    Misiurewicz, Michal

    2013-01-01

    If students are presented the standard proof of irrationality of [square root]2, can they generalize it to a proof of the irrationality of "[square root]p", "p" a prime if, instead of considering divisibility by "p", they cling to the notions of even and odd used in the standard proof?

  20. Genotype x environment interactions in Angus, Brahman, and reciprocal-cross cows and their calves grazing common bermudagrass, endophyte-infected tall fescue pastures, or both forages.

    Science.gov (United States)

    Brown, M A; Brown, A H; Jackson, W G; Miesner, J R

    2000-03-01

    Reproductive and preweaning data on 190 Angus (A x A), Brahman (B x B), and reciprocal-cross cows (A x B and B x A) and 434 two- and three-breed-cross calves managed on common bermudagrass (BG), endophyte-infected tall fescue (E+), or a combination of both forages (ROT) were used to evaluate the interaction of forage type with individual and maternal heterosis and maternal and grandmaternal breed effects. Cows were born from 1988 to 1991, and calves sired by 13 Polled Hereford bulls were born from 1995 to 1997. Heterosis for calving rate was larger on E+ than on BG or ROT (P < .05), whereas maternal effects were larger on BG than on ROT (P < .10). Maternal heterosis for birth weight was negative on BG (P < .11) but positive on E+ and ROT (P < .10). Grandmaternal effects were evident on BG (P < .10) and E+ (P < .01) but not on ROT. Forage effects were generally substantial for 205-d weight, calf weaning hip height, and calf weaning weight:height ratio; BG was highest, ROT was intermediate, and E+ was lowest. Maternal heterosis for these traits was generally greater on E+ than on BG (P < .10). Grandmaternal effects for 205-d weight, hip height, and weight:height ratio were not important on any forage. Heterosis for weaning weight per cow exposed was substantial on all forages (P < .01) and was significantly greater on E+ (P < .01) than on BG or ROT, but maternal effects were not significant. Thus, we observed more advantage to Brahman-cross cows over purebreds on E+ than on BG. We also observed that moving cows and calves from E+ to BG in the summer will alleviate some, but not all, of the deleterious effects of E+ on calf growth, although it may be more beneficial for reproductive traits in purebred cows.

  1. 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...

  2. Scaling root processes based on plant functional traits (Invited)

    Science.gov (United States)

    Eissenstat, D. M.; McCormack, M. L.; Gaines, K.; Adams, T.

    2013-12-01

    There are great challenges to scaling root processes as variation across species and variation of a particular species over different spatial and temporal scales is poorly understood. We have examined tree species variation using multispecies plantings, often referred to by ecologists as 'common gardens'. Choosing species with wide variation in growth rate, root morphology (diameter, branching intensity) and root chemistry (root N and Ca concentration), we found that variation in root lifespan was well correlated with plant functional traits across 12 species. There was also evidence that localized liquid N addition could increase root lifespan and localized water addition diminished root lifespan over untreated controls, with effects strongest in the species of finest root diameter. In an adjacent forest, we have also seen tree species variation in apparent depth of rooting using water isotopes. In particular species of wood anatomy that was ring porous (e.g. oaks) typically had the deepest rooting depth, whereas those that had either diffuse-porous sapwood (maples) or tracheid sapwood (pines) were shallower rooted. These differences in rooting depth were related to sap flux of trees during and immediately after periods of drought. The extent that the patterns observed in central Pennsylvania are modulated by environment or indicative of other plant species will be discussed.

  3. 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.

  4. Genomic Regions Influencing Seminal Root Traits in Barley.

    Science.gov (United States)

    Robinson, Hannah; Hickey, Lee; Richard, Cecile; Mace, Emma; Kelly, Alison; Borrell, Andrew; Franckowiak, Jerome; Fox, Glen

    2016-03-01

    Water availability is a major limiting factor for crop production, making drought adaptation and its many component traits a desirable attribute of plant cultivars. Previous studies in cereal crops indicate that root traits expressed at early plant developmental stages, such as seminal root angle and root number, are associated with water extraction at different depths. Here, we conducted the first study to map seminal root traits in barley ( L.). Using a recently developed high-throughput phenotyping method, a panel of 30 barley genotypes and a doubled-haploid (DH) population (ND24260 × 'Flagship') comprising 330 lines genotyped with diversity array technology (DArT) markers were evaluated for seminal root angle (deviation from vertical) and root number under controlled environmental conditions. A high degree of phenotypic variation was observed in the panel of 30 genotypes: 13.5 to 82.2 and 3.6 to 6.9° for root angle and root number, respectively. A similar range was observed in the DH population: 16.4 to 70.5 and 3.6 to 6.5° for root angle and number, respectively. Seven quantitative trait loci (QTL) for seminal root traits (root angle, two QTL; root number, five QTL) were detected in the DH population. A major QTL influencing both root angle and root number (/) was positioned on chromosome 5HL. Across-species analysis identified 10 common genes underlying root trait QTL in barley, wheat ( L.), and sorghum [ (L.) Moench]. Here, we provide insight into seminal root phenotypes and provide a first look at the genetics controlling these traits in barley. Copyright © 2016 Crop Science Society of America.

  5. Genomic Regions Influencing Seminal Root Traits in Barley

    Directory of Open Access Journals (Sweden)

    Hannah Robinson

    2016-03-01

    Full Text Available Water availability is a major limiting factor for crop production, making drought adaptation and its many component traits a desirable attribute of plant cultivars. Previous studies in cereal crops indicate that root traits expressed at early plant developmental stages, such as seminal root angle and root number, are associated with water extraction at different depths. Here, we conducted the first study to map seminal root traits in barley ( L.. Using a recently developed high-throughput phenotyping method, a panel of 30 barley genotypes and a doubled-haploid (DH population (ND24260 × ‘Flagship’ comprising 330 lines genotyped with diversity array technology (DArT markers were evaluated for seminal root angle (deviation from vertical and root number under controlled environmental conditions. A high degree of phenotypic variation was observed in the panel of 30 genotypes: 13.5 to 82.2 and 3.6 to 6.9° for root angle and root number, respectively. A similar range was observed in the DH population: 16.4 to 70.5 and 3.6 to 6.5° for root angle and number, respectively. Seven quantitative trait loci (QTL for seminal root traits (root angle, two QTL; root number, five QTL were detected in the DH population. A major QTL influencing both root angle and root number (/ was positioned on chromosome 5HL. Across-species analysis identified 10 common genes underlying root trait QTL in barley, wheat ( L., and sorghum [ (L. Moench]. Here, we provide insight into seminal root phenotypes and provide a first look at the genetics controlling these traits in barley.

  6. Growth kinetics and efficacy as parameters for ranking and selecting biocontrol agents that reduce pink rot in stored potatoes

    Science.gov (United States)

    Increased production of organic agricultural products and the relative ineffectiveness of traditional control measures support development of new biocontrol technologies for use against pink rot infections in storage. The microbiota of 84 different agricultural soils was individually transferred to...

  7. NODC Standard Format Pathology Data Sets (1973-1975): Fin Rot (F006) Data (NODC Accession 0014147)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Fin Rot (F006) dataset contains data from examinations of the biological condition of diseased fishes. For tow samples collected, data include: total number of...

  8. 3D Ground Penetrating Radar to Detect Tree Roots and Estimate Root Biomass in the Field

    Directory of Open Access Journals (Sweden)

    Shiping Zhu

    2014-06-01

    Full Text Available The objectives of this study were to detect coarse tree root and to estimate root biomass in the field by using an advanced 3D Ground Penetrating Radar (3D GPR system. This study obtained full-resolution 3D imaging results of tree root system using 500 MHz and 800 MHz bow-tie antennas, respectively. The measurement site included two larch trees, and one of them was excavated after GPR measurements. In this paper, a searching algorithm, based on the continuity of pixel intensity along the root in 3D space, is proposed, and two coarse roots whose diameters are more than 5 cm were detected and delineated correctly. Based on the detection results and the measured root biomass, a linear regression model is proposed to estimate the total root biomass in different depth ranges, and the total error was less than 10%. Additionally, based on the detected root samples, a new index named “magnitude width” is proposed to estimate the root diameter that has good correlation with root diameter compared with other common GPR indexes. This index also provides direct measurement of the root diameter with 13%–16% error, providing reasonable and practical root diameter estimation especially in the field.

  9. Gnomoniopsis castanea is the main agent of chestnut nut rot in Switzerland

    Directory of Open Access Journals (Sweden)

    Francesca G. DENNERT

    2015-09-01

    Full Text Available Nuts of sweet chestnut have been an important food source for the alpine population in Switzerland since the Middle Ages and are still valued today for the preparation of traditional food commodities. Nut quality is reduced by insect damage and by various pathogenic fungi. In the last few years, producers and consumers perceived an increase of brown nut rot; while the nut rot agent Gnomoniopsis castanea was reported locally in southern Switzerland, its presence has not been investigated over large areas until now. This study assessed the incidence of brown nut rot and identified the causal agent present in Switzerland. Fully ripened nuts were collected from the main sweet chestnut growing areas of Switzerland. A filamentous fungus morphologically identified as G. castanea was isolated from 10 to 91% of the sampled nuts, despite only 3 to 21% of the sampled nuts showing brown rot symptoms. This fungus was isolated from symptomatic chestnuts as well as from apparently healthy chestnuts. Our results suggest a possible endophytic lifestyle in ripened nuts as well as in branches, leaves and unripe nuts as previously found. Species identity of 45 isolates was confirmed by EF-1alpha, beta-tubulin and ITS sequencing. Concatenation of β-tubulin and calmodulin sequences showed that several haplotypes were present at each sampling locality. No other nut rot pathogens could be isolated in this study, suggesting that G. castanea is the main causal agent of nut rot in Switzerland. The presence of this species is reported for the first time in a site in northern Switzerland. Further studies are needed to assess the influence of meteorological conditions and chestnut varieties on the incidence of G. castanea in order to provide prevention strategies for chestnut growers. Normal 0 21 false false false FR-CH X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso

  10. Gene cloning and heterologous expression of pyranose 2-oxidase from the brown-rot fungus, Gloeophyllum trabeum

    Science.gov (United States)

    Diane Dietrich; Casey Crooks

    2009-01-01

    A pyranose 2-oxidase gene from the brown-rot basidiomycete Gloeophyllum trabeum was isolated using homology-based degenerate PCR. The gene structure was determined and compared to that of several pyranose 2-oxidases cloned from white-rot fungi. The G. trabeum pyranose 2-oxidase gene consists of 16 coding exons with canonical promoter CAAT and TATA elements in the 5’UTR...

  11. Root phenology at Harvard Forest and beyond

    Science.gov (United States)

    Abramoff, R. Z.; Finzi, A.

    2013-12-01

    Roots are hidden from view and heterogeneously distributed making them difficult to study in situ. As a result, the causes and timing of root production are not well understood. Researchers have long assumed that above and belowground phenology is synchronous; for example, most parameterizations of belowground carbon allocation in terrestrial biosphere models are based on allometry and represent a fixed fraction of net C uptake. However, using results from metaanalysis as well as empirical data from oak and hemlock stands at Harvard Forest, we show that synchronous root and shoot growth is the exception rather than the rule. We collected root and shoot phenology measurements from studies across four biomes (boreal, temperate, Mediterranean, and subtropical). General patterns of root phenology varied widely with 1-5 production peaks in a growing season. Surprisingly, in 9 out of the 15 studies, the first root production peak was not the largest peak. In the majority of cases maximum shoot production occurred before root production (Offset>0 in 32 out of 47 plant sample means). The number of days offset between maximum root and shoot growth was negatively correlated with median annual temperature and therefore differs significantly across biomes (ANOVA, F3,43=9.47, pGrowth form (woody or herbaceous) also influenced the relative timing of root and shoot growth. Woody plants had a larger range of days between root and shoot growth peaks as well as a greater number of growth peaks. To explore the range of phenological relationships within woody plants in the temperate biome, we focused on above and belowground phenology in two common northeastern tree species, Quercus rubra and Tsuga canadensis. Greenness index, rate of stem growth, root production and nonstructural carbohydrate content were measured beginning in April 2012 through August 2013 at the Harvard Forest in Petersham, MA, USA. Greenness and stem growth were highest in late May and early June with one clear

  12. The Cultivation of Antagonistic Bacteria in Irradiated Sludge for Biological Control of Soft Rot Erwinias : Screening of Antagonistic Bacteria for biological Control of Soft Rot Erwinias

    International Nuclear Information System (INIS)

    Sermkiattipong, Ng.; Sangsuk, L; Rattanapiriyakul, P; Dejsirilert, S.; Thaveechai, N.

    1998-01-01

    Pure cultures of 57 bacterial isolates for antagonistic activity screening were isolated from three areas of soft rot infested vegetable soil and 58 isolates were obtained from commercial seed compost and seed compost product of Division of Soil and Water Conservation, Department of Land Development. A total of 115 bacterial isolates were evaluated for antagonizing activity against Erwinia carotovora subsp. atroceptica in vitro. Out of them, 18 isolates were antagonists by showing zone of inhibition ranging from 1 to 17 mm by diameter. Most of antagonistic bacteria were identified as Bacillus spp. whereas only one isolate was Pseudomonas vesicularis

  13. White-rot fungal response to fresh and photolytically-weathered pyrogenic organic matter

    Science.gov (United States)

    Gibson, C. D.; Berry, T. D.; Wang, R.; Bird, J. A.; Filley, T. R.

    2013-12-01

    Pyrogenic organic matter (PyOM or biochar) is the product of the incomplete combustion of biomass. A better understanding of the microbial-mediated degradation of PyOM is critical to assess its role in soil C sequestration and to serve as an agricultural amendment. Recent studies have shown that PyOM additions can prime native soil C but results have been inconsistent, with studies reporting no effect, an increase, or decrease in C mineralization. This study investigated the ability of saprotrophic white-rot fungus, Trametes versicolor, to decompose an unaltered 'fresh' PyOM and a photo-oxidized PyOM. In addition, we measured PyOM-induced priming effects on the mineralization of malt extract agar media (MEA). Enriched (13C) Pinus banksiana-derived PyOM, produced at 450oC under N2, was added fresh and after 4 weeks exposure to 254 nm light to MEA. Vials containing the various types of media were then monitored for CO2 evolution and oxidative enzyme activity. We found that MEA C respired was stimulated (positive priming) by photolyzed PyOM and was inhibited with fresh PyOM addition (negative priming) relative to controls. Vetryl alcohol addition, a laccase production stimulant, resulted in less activity in the presence of PyOM compared with a control, indicating PyOM may disrupt enzyme induction processes. Loss of PyOM-13CO2 was 0.2% (× 0.001) for fresh PyOM and 1.2% (×0.001) for photolyzed PyOM C during 10 weeks averaged across media treatments. While MEA C mineralization decreased after fresh PyOM addition, both oxidative (laccase and manganese peroxidase) and hydrolytic (β glucosidase) enzyme production increased with fresh PyOM in the absence of veratryl alcohol. However, there was a decrease in its presence. These results suggest that the physiological response of this common wood decay fungus to PyOM is complex and responsive to enzymatic triggers but that PyOM itself can act to promote or suppress overall litter or soil decay by fungi.

  14. Annosus Root disease of Western Conifers (FIDL)

    Science.gov (United States)

    Craig L. Schmitt; John R. Parmeter; John T. Kliejunas

    2000-01-01

    Annosus root disease is found on all western conifer species but is of most concern on true firs, hemlocks, and pines. Incense cedar, coast redwood and sequoia are sometimes infected in California. Western juniper is infected throughout its range. Annosus is common and causes extensive decay in old-growth western and mountain hemlock stands. Many mixed conifer stands...

  15. Some pitfalls in unit root testing

    NARCIS (Netherlands)

    Bakker, B.B.; Koning, Ruud H.

    1991-01-01

    Testing for unit roots is now common practice for economists. The most popular procedure is the approach developed by Dickey and Fuller (1979, 1981), which only requires running appropriately specified regressions. However, application of the Dickey-Fuller procedure requires that the disturbance

  16. Bullying in nursing: roots, rationales, and remedies.

    Science.gov (United States)

    Szutenbach, Mary Pat

    2013-01-01

    Bullying and incivility are sadly, far too common in today's healthcare workplaces. This article reviews early to current literature, identifies types of bullying, offers four root causes, and suggests responses to impact these causes using Gibbs' Reflective Cycle, biblical Scripture, and an allegory "How to Swim with Sharks."

  17. Grass Rooting the System

    Science.gov (United States)

    Perlman, Janice E.

    1976-01-01

    Suggests a taxonomy of the grass roots movement and gives a general descriptive over view of the 60 groups studied with respect to origin, constituency, size, funding, issues, and ideology. (Author/AM)

  18. 3-D Printed Fabry–Pérot Resonator Antenna with Paraboloid-Shape Superstrate for Wide Gain Bandwidth

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2017-11-01

    Full Text Available A three-dimensional (3-D printed Fabry–Pérot resonator antenna (FPRA, which designed with a paraboloid-shape superstrate for wide gain bandwidth is proposed. In comparison with the commonly-adopted planar superstrate, the paraboloid-shape superstrate is able to provide multiple resonant heights and thus satisfy the resonant condition of the FPRA in a wide frequency band. A FPRA working at 6 GHz is designed, fabricated, and tested. Considering the fabrication difficulty caused by its complex structure, the prototype antenna was fabricated by using the 3-D printing technology, i.e., all components of the prototype antenna were printed with photopolymer resin and then treated by the surface metallization process. Measurement results agree well with the simulation results, and show the 3-D printed FPRA has a |S11| < −10 dB impedance bandwidth of 12.4%, and a gain of 16.8 dBi at its working frequency of 6 GHz. Moreover, in comparison with the planar superstrate adopted in traditional FPRAs, the paraboloid-shape superstrate of the proposed FPRA significantly improves the 3-dB gain bandwidth from 6% to 22.2%.

  19. Pectobacterium carotovorum subsp. carotovorum – the Causal Agent of Calla Soft Rot in Serbia and Montenegro

    Directory of Open Access Journals (Sweden)

    Milan Ivanović

    2009-01-01

    Full Text Available Bacterial strains were isolated from above- and underground parts of diseased calla plants originating from different localities in Serbia and one locality in Montenegro. They were characterized by studying their pathogenic, cultural, biochemical and physiologicalcharacteristics. All investigated strains caused soft rot of calla leaf stalks, potato slices and aloe leaves, and induced hypersensitive reaction on tobacco. Bacteriological properties of the strains indicated that symptoms on calla plants were caused by Gram-negative, nonfluorescent, oxidase negative, catalase positive and facultatively anaerobic bacterium belonging to the genus Pectobacterium. The investigated strains grew at 37ºC and in 5% NaCl, utilised lactose and trechalose, and produced neither indol nor lecitinase. These results, as well as the characteristic growth on Logan’s differential medium indicated that soft rot of tuber and stem base of calla plants was caused by Pectobacterium carotovorum subsp. carotovorum. This is the first report of this pathogen affecting calla plants in Serbia.

  20. Fungi associated with fruit crown rot in organic banana (Musa spp. L. in Piura, Peru

    Directory of Open Access Journals (Sweden)

    René Aguilar Anccota

    2013-05-01

    Full Text Available The department of Piura is the principal banana-producing zone in Peru, sharing 87% of exportations. In this zone, one of the most important postharvest diseases is crown rot. The economic loses attributed to this disease are estimated to be between 25 and 30% of organic bananas exported. The objective of this study was to identify the causal agents associated with this disease. Samples taken refrigerated fruit from the areas of Querecotillo, Salitral and Mallares were taken and selected after the fact. Thielaviopsis paradoxa, Lasiodiplodia theobromae, Colletotrichum musae and Fusarium verticilloides. In order to demonstrate the pathogenicity of the isolated species, inoculations were given in the area of the crown of the fruit on healthy bananas. These fungi caused symptoms of infection in different proportions, concluding that crown rot is a disease with a complex etiology.

  1. 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...... planes in all degraded samples after roughly 20% weight loss, as well as a decrease in the average observed relative peak width at 2¿ = 22.2°. These results may indicate a disruption of the outer most semi-crystalline cellulose chains comprising the wood microfibril. X-ray diffraction analysis of wood...... subjected to biological attack by fungi may provide insight into degradative processes and wood cellulose structure....

  2. Biological Control Of The Egyptian Brown Rot In Potato (Solanum Tuberosum L.)

    International Nuclear Information System (INIS)

    Salem, E.A.; Askora, A. M.

    2012-01-01

    Pseudomonas fluorescence, P. aeruginosa, Bacillus subtillus and streptomyces spp. Were used in control of Ralstonia solanacearum, the casual agent of brown rot in potato. In vitro, antagonistic activities showed that streptomyces spp. was the most antagonistic followed by P. fluorescence, Bacillus subtilus and P. aeruginosa respectively. Also, in vivo, biological control of R. solanacearum showed that Streptomyces spp. was found to reduce the percentage of brown rot infection to 5% followed by P. fluorescence, Bacillus subtilus and P. aeruginosa reducing the percentage of infection to 15 , 25 and 40%, respectively. Also, the disease severity when using Streptomyces spp. and P. fluorescence was reduced from 5 to 1 and reduced from 5 to 2 when using Bacillus subtilus and P. aeruginosa.

  3. 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

    2015-08-03

    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. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Microbial detoxification of waste rubber material by wood-rotting fungi.

    Science.gov (United States)

    Bredberg, Katarina; Andersson, B Erik; Landfors, Eva; Holst, Olle

    2002-07-01

    The extensive use of rubber products, mainly tires, and the difficulties to recycle those products, has resulted in world wide environmental problems. Microbial devulcanisation is a promising way to increase the recycling of rubber materials. One obstacle is that several microorganisms tested for devulcanisation are sensitive to rubber additives. A way to overcome this might be to detoxify the rubber material with fungi prior to the devulcanisation. In this study, 15 species of white-rot and brown-rot fungi have been screened with regard to their capacity to degrade an aromatic model compound in the presence of ground waste tire rubber. The most effective fungus, Resinicium bicolor, was used for detoxification of rubber material. Increase in growth of the desulfurising bacterium Thiobacillus ferrooxidans in presence of the rubber treated with Resinicium bicolor compared to untreated rubber demonstrated that detoxification with fungi is possible.

  5. Rooting an Android Device

    Science.gov (United States)

    2015-09-01

    1. Overview The purpose of this document is to demonstrate how to gain administrative privileges on an Android device. The term “rooting” is...is applicable for the Samsung Galaxy S3 as well as many other Android devices, but there are several steps involved in rooting an Android device (as...root access has been granted. 4. Conclusion This document serves as a tutorial on how to grant user administrative privilege to an Android device by

  6. Imaging mass spectrometry and genome mining reveal highly antifungal virulence factor of mushroom soft rot pathogen.

    Science.gov (United States)

    Graupner, Katharina; Scherlach, Kirstin; Bretschneider, Tom; Lackner, Gerald; Roth, Martin; Gross, Harald; Hertweck, Christian

    2012-12-21

    Caught in the act: imaging mass spectrometry of a button mushroom infected with the soft rot pathogen Janthinobacterium agaricidamnosum in conjunction with genome mining revealed jagaricin as a highly antifungal virulence factor that is not produced under standard cultivation conditions. The structure of jagaricin was rigorously elucidated by a combination of physicochemical analyses, chemical derivatization, and bioinformatics. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Atrazine dissipation in a biobed system inoculated with immobilized white-rot fungi

    OpenAIRE

    Elgueta, Sebastian; Santos, Cledir; Santos, C.; Lima, Nelson; Diez, M. C.

    2016-01-01

    Due to the environmental concerns about the herbicide atrazine accumulation in food products and water reservoirs, there is a need to develop safe and economical methods for its dissipation. The main aim of this study was to evaluate the atrazine dissipation in a biobed system inoculated with immobilized white-rot fungi in a pelletized support (PS). All fungal isolates evaluated were efficient in colonizing the surface and inner parts of the PS and without differences observed in the coloniza...

  8. Treatment of micropollutants in municipal wastewater using white-rot fungi

    OpenAIRE

    Margot, Jonas; Vargas, Micaela; Contijoch, Andreu; Barry, David Andrew; Holliger, Christof

    2014-01-01

    Treatment of micropollutants such as pharmaceuticals and pesticides in municipal wastewater is challenging due to their very low concentrations (ng/l to µg/l), their relatively low biodegradability, and their different physico-chemical characteristics. One potential way to improve micropollutant biodegradation in wastewater treatment plant (WWTP) effluent is by using microorganisms such as white-rot fungi that produce powerful unspecific oxidative exo-enzymes (laccase, peroxidase) that are ab...

  9. Degradation of Phenanthrene by a chilean white rot fungus Anthracophyllum discolor

    International Nuclear Information System (INIS)

    Acevedo, F.; Cuevas, R.; Rubilar, O.; Tortella, G.; Diez, M. C.

    2009-01-01

    Anthracophyllum discolor, a white rot fungus of southern Chile, has been an efficient degrader of clorophenols and azo dyes. This fungus produces ligninolytic enzymes being manganese peroxidase (Mn)) the major one produced. The main purpose of this study was to evaluate the effect of phenanthrene concentration of ligninolytic activity of A. Discolor measured by poly R-478 decolorazation, and to evaluate the potential of this fungus for degrading phenanthrene in liquid media. (Author)

  10. White-rot fungi in phenols, dyes and other xenobiotics treatment – a brief review

    OpenAIRE

    Tišma, Marina; Zelić, B.; Vasić-Rački, Đurđa

    2010-01-01

    Bioremediation is an attractive technology that utilizes the metabolic potential of microorganisms in order to clean up the environmental pollutants to the less hazardous or non-hazardous forms with less input of chemicals, energy and time. White-rot fungi are unique organisms that show the capacities of degrading and mineralizing lignin as well as organic, highly toxic and recalcitrant compounds. The key enzymes of their metabolism are extracellular lignolytic enzymes that enable fungi to to...

  11. Control of Fusarium verticillioides, cause of ear rot of maize, by Pseudomonas fluorescens.

    Science.gov (United States)

    Nayaka, Siddaiah Chandra; Shankar, Arakere C Udaya; Reddy, Munagala S; Niranjana, Siddapura R; Prakash, Harishchandra S; Shetty, Hunthrike S; Mortensen, Carmen N

    2009-07-01

    Maize is one of the staple food crops grown in India. Fusarium verticillioides (Sacc.) Nirenberg is the most important fungal pathogen of maize, associated with diseases such as ear rot and kernel rot. Apart from the disease, it is capable of producing fumonisins, which have elicited considerable attention over the past decade owing to their association with animal disease syndromes. Hence, the present study was conducted to evaluate ecofriendly approaches by using a maize rhizosphere isolate of Pseudomonas fluorescens (Trev.) Mig. and its formulation to control ear rot disease and fumonisin accumulation, and also to study the capacity to promote growth and yield of maize. In vitro assays were conducted to test the efficacy of P. fluorescens as a seed treatment on seed germination, seedling vigour and also the incidence of F. verticillioides in different maize cultivars. The field trials included both seed treatment and foliar spray. For all the experiments, P. fluorescens was formulated using corn starch, wheat bran and talc powder. In each case there were three different treatments of P. fluorescens, a non-treated control and chemical control. Pure culture and the formulations, in comparison with the control, increased plant growth and vigour as measured by seed germination, seedling vigour, plant height, 1000 seed weight and yield. P. fluorescens pure culture used as seed treatment and as spray treatment enhanced the growth parameters and reduced the incidence of F. verticillioides and the level of fumonisins to a maximum extent compared with the other treatments. The study demonstrates the potential role of P. fluorescens and its formulations in ear rot disease management. The biocontrol potential of this isolate is more suited for fumonisin reduction in maize kernels intended for human and animal feed. (c) 2009 Society of Chemical Industry.

  12. Lignin as a facilitator, not a barrier, during saccharification by brown rot fungi

    Energy Technology Data Exchange (ETDEWEB)

    Schilling, Jonathan S. [Univ. of Minnesota, Minneapolis, MN (United States); Tschirner, Ulrike [Univ. of Minnesota, Minneapolis, MN (United States); Blanchette, Robert A [Univ. of Minnesota, Minneapolis, MN (United States); Filley, Timothy [Purdue Univ., West Lafayette, IN (United States)

    2012-11-28

    This research focused on the biology of a group of wood-degrading fungi that cause brown rot in wood, with particular attention to the potential to mimic this biological approach ex situ for bioprocessing lignocellulosic biomass. Supported by the long-standing theory that these fungi use a two-step oxidative/enzymatic approach during brown rot, our team’s objectives were as follows: 1) to determine the discrete timing of lignin modifications, 2) to correlate these alterations with biocatalyst efficiency and ingress into plant cell walls, and 3) to reproduce modifications prior to saccharification for efficient bioprocessing. The core findings of our research were that 1) lignin modifications occur nearly coincident with enzyme secretion during brown rot and 2) there is no specificity to the benefit that a brown rot pretreatment has on the efficacy of cellulases – it is a general enhancement best predicted by chemical changes to lignin and side-chain hemicellulose sugars. In our work, this meant we could attain and predict broad improvements in saccharification using commercial cellulase cocktails, in some cases more than three-fold of that in untreated biomass. This project was completed with minimal variance from the original project management plan (PMP), resulting in fourteen presentations and posters, four peer-reviewed publications, and one additional publication now in review. The publications have been valuable to other scientists working toward similar goals and have been cited in thirteen peer-reviewed publications written by others since 2010. We are working with ADM to advance application options for industry, building on the lessons learned during this DOE award period.

  13. Degradation of Phenanthrene by a chilean white rot fungus Anthracophyllum discolor

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, F.; Cuevas, R.; Rubilar, O.; Tortella, G.; Diez, M. C.

    2009-07-01

    Anthracophyllum discolor, a white rot fungus of southern Chile, has been an efficient degrader of clorophenols and azo dyes. This fungus produces ligninolytic enzymes being manganese peroxidase (Mn) the major one produced. The main purpose of this study was to evaluate the effect of phenanthrene concentration of ligninolytic activity of A. Discolor measured by poly R-478 decolorazation, and to evaluate the potential of this fungus for degrading phenanthrene in liquid media. (Author)

  14. Adaptive significance of root grafting in trees

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.; Jones, R.

    1988-12-31

    Root grafting has long been observed in forest trees but the adaptive significance of this trait has not been fully explained. Various authors have proposed that root grafting between trees contributes to mechanical support by linking adjacent root systems. Keeley proposes that this trait would be of greatest advantage in swamps where soils provide poor mechanical support. He provides as evidence a greenhouse study of Nyssa sylvatica Marsh in which seedlings of swamp provenance formed between-individual root grafts more frequently than upland provenance seedlings. In agreement with this within-species study, Keeley observed that arid zone species rarely exhibit grafts. Keeley also demonstrated that vines graft less commonly than trees, and herbs never do. Since the need for mechanical support coincides with this trend, these data seem to support his model. In this paper, the authors explore the mechanisms and ecological significance of root grafting, leading to predictions of root grafting incidence. Some observations support and some contradict the mechanical support hypothesis.

  15. Root caries: a survey of Queensland dentists.

    Science.gov (United States)

    Garton, B J; Ford, P J

    2013-08-01

    Root caries stands to be a significant burden for Australia's ageing population. The objective of this study was to describe Queensland dental practitioners' perceptions of root caries prevalence, presentation and predisposing factors as well as diagnosis and recording practices. Using the Queensland Dental Board register, all 2,515 dentists and dental specialists practising in Queensland were invited to participate in a questionnaire-based postal survey. Of the 660 responses received, 638 were included for final analysis. Use of diagnostic measures such as surface elasticity and contour were reported frequently. A majority of respondents (77%) reported not recording root caries in a way that could be distinguished from coronal caries. Dietary analysis was the most commonly reported adjunctive aid for risk assessment. Recommendations for use of remineralizing agents were frequently reported (home use 90%; in office use 71%). Salivary impairment was reported to be an important risk factor for root caries by 93% of respondents, but only 18% reported performing salivary analysis. A large proportion of respondents (32%) considered patients with diabetes to be of low or no risk of root caries. While the Queensland dental practitioners who participated in this survey demonstrated an awareness of root caries and its predisposing factors, clinical risk assessment particularly for patients with diabetes should be further examined. © 2013 John Wiley & Sons A/S.

  16. Effect of climate on the distribution of Fusarium spp. causing crown rot of wheat in the Pacific Northwest of the United States.

    Science.gov (United States)

    Poole, Grant J; Smiley, Richard W; Walker, Carl; Huggins, David; Rupp, Richard; Abatzoglou, John; Garland-Campbell, Kimberly; Paulitz, Timothy C

    2013-11-01

    Fusarium crown rot (FCR) is one of the most widespread root and crown diseases of wheat in the Pacific Northwest (PNW) of the United States. Our objectives were to characterize crown rot severity and distribution throughout the PNW by conducting a survey of 210 fields covering the diverse dryland wheat-producing areas of Washington and Oregon and to utilize a factor analysis statistical approach to determine the effects of climate and geography on species distribution and disease severity. Climatic variables were based on 30-year averages and 2008 and 2009 separately (the 2 years of the survey). Mean annual temperature, mean temperature in the coldest month, mean temperature in the warmest month, mean annual precipitation, snowfall, elevation, soil type, and cropping intensity were highly intercorrelated. The factor analysis of the climate variables resulted in the development of two latent factors that could be used as predictor variables in logistic regression models for the presence or absence of Fusarium spp. and of FCR disease scores. Isolates of Fusarium spp. were recovered from 99% of 105 fields sampled in 2008 and 97% of fields in 2009. There were differences between years for responses of FCR and nodes scores, and isolations of Fusarium pseudograminearum with more significant results in 2008, due to warmer drier weather. Results of the factor analysis showed that the distribution of F. pseudograminearum occurred in a greater frequency in areas of the PNW at lower elevations with lower moisture and higher temperatures in 2008, whereas F. culmorum occurred in greater frequency in areas at higher elevations with moderate to high moisture and cooler temperatures consistently across both years. Disease scores increased with increasing levels of factors 1 (primarily temperature) and 2 (primarily precipitation). Both the frequency of pathogen species and disease scores were influenced by the year, indicating that soilborne pathogens are responsive to short

  17. effects of different concentrations of auxins on rooting and root

    African Journals Online (AJOL)

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    ABSTRACT: The effect of auxins and their different concentrations on rooting and root ... primary root length and the longest primary root was recorded with the ... ceuticals, lubricants, foods, electrical insulators, .... stem cuttings of jojoba treated with IBA and NAA, .... increasing cell division and enlargement at each.

  18. Potential of bulb-associated bacteria for biocontrol of hyacinth soft rot caused by Dickeya zeae.

    Science.gov (United States)

    Jafra, S; Przysowa, J; Gwizdek-Wiśniewska, A; van der Wolf, J M

    2009-01-01

    Dickeya zeae is a pectinolytic bacterium responsible for soft rot disease in flower bulb crops. In this study, the possibility of controlling soft rot disease in hyacinth by using antagonistic bacteria isolated from hyacinth bulbs was explored. Bacterial isolates with potential for biocontrol were selected on the basis of antibiosis against D. zeae, siderophore production, and the N-acyl homoserine lactones (AHLs)-inactivation. In in vitro assays, 35 out of 565 hyacinth-associated bacterial isolates produced antimicrobial substances against D. zeae, whereas 20 degraded AHLs, and 35 produced siderophores. Isolates of interest were identified by 16S rDNA sequence analysis and reaction in BIOLOG tests. Twenty-six isolates that differed in characteristics were selected for pathogenicity testing on hyacinth cultivars, Pink Pearl and Carnegie. Two strains identified as Rahnella aquatilis and one as Erwinia persicinus significantly reduced tissue maceration caused by D. zeae 2019 on hyacinth bulbs, but not on leaves. Hyacinth bulbs harbour bacteria belonging to different taxonomic groups that are antagonistic to D. zeae, and some can attenuate decay of bulb tissue. Selected hyacinth-associated bacterial isolates have potential for control of soft rot disease caused by D. zeae in hyacinth bulb production.

  19. Molecular Detection of Monilinia fructigena as Causal Agent of Brown Rot on Quince

    Directory of Open Access Journals (Sweden)

    Jovana Hrustić

    2012-01-01

    Full Text Available Species of the genus Monilinia are important causal agents of fruit rot on pome and stone fruits in Serbia. The pathogen is very harmful, especially on small properties and cottage plantations where intensive control measures are not applied. Quince is importanthost for the pathogens of this genus. During spring 2010, intensive occurrence of mummified fruits overwintering on branches of the quince was observed. The pathogen was isolated using standard phytopathological methods. Pathogenicity of eight obtained isolates was tested by artificial inoculation of injured apple fruits. Identification was performed according to pathogenic, morphological and ecological properties, and was confirmed by Multiplex polimeraze chain reaction, PCR. All the isolates studied caused brown rot on inoculated apple fruits. The isolates form light yellow colonies with lobate margins,with single-celled, transparent, elliptical or oval conidia in chains, regardless temperature or light presence. Sclerotia are observed in 14 days old cultures. The highest growth rate of most of the isolates is at 27°C and in dark. Based on studied pathogenic, morphological and ecological characteristics, it was found that the Monilinia fructigena is causal agent of brown rot of quince. Using specific primers (MO368-5, MO368-8R, MO368-10R, Laxa-R2for detection of Monilinia species in Multiplex PCR reaction, the expected fragment 402 bp in size was amplified, which confirmed that the studied isolates belonged to the speciesM. fructigena.

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

    Directory of Open Access Journals (Sweden)

    Soo-Sang Hahm

    2014-03-01

    Full Text Available 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 sporangia were sub-globose, brownish and 6-10 μm in size. Sporangia were globose, blackish and 87-116 μm in size. Sporangiospores were irregularly oval and sub-globose, brownish 4-8 μm in size. On the basis of mycological characteristics, analyzing sequences of internal transcribed spacer region of ribosomal DNA, and pathogenicity test on host plants, the causal fungus was identified as R. oryzae. This is the first report of Rhizopus soft rot on lily caused by R. oryzae in Korea.