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Site: http://phys.org/biology-news/

The target is the fearsome fungal disease wheat blast. The pathogen was spotted in Bangladesh in February this year—its first report in Asia. Wheat is the second major food source in Bangladesh, after rice. The blast disease has, so far, caused up to 90% yield losses in more than 15,000 hectares. Scientists fear that the pathogen could spread further to other wheat growing areas in South Asia. The UK and Bangladeshi teams are making raw genetic data for the wheat blast pathogen available on a new website—http://www.wheatblast.net—and inviting others to do the same. Professor Sophien Kamoun, of The Sainsbury Laboratory in Norwich, who is leading the project, said that a wide cultural change is needed for scientists to optimally address new threats to food security. "I have a beef with the way that research is typically done. We need a fundamentally new approach to sharing genetic data for emerging plant diseases," he said. "We need to generate and make data public more rapidly and seek input from a larger crowd because, collectively, we are better able to answer questions." Professor Kamoun, with colleagues at The Genome Analysis Centre and John Innes Centre in Norwich, and with Professor Tofazzal Islam's Team of Bangabndhu Sheikh Mujubur Rahman Agricultural University (BSMRAU) in Bangladesh, is hoping that the wheatblast.net website, together with an accompanying Facebook page, will provide a hub for information, collaboration and comment. They are basing the site on their successful Open Ash Dieback website, which brought scientists together in the fight against ash dieback disease. The blast fungus normally infects rice and over 50 types of grasses. Occasionally, a blast fungus strain would jump from one host to another resulting in a new disease. Such a "host jump" to wheat has happened in Brazil in the 1980s. The wheat blast pathogen is now rife in South America, where it infects up to 3 million hectares and causes serious crop losses. Prof Kamoun and colleagues are working with Professor Tofazzal Islam's team, of the Department of Biotechnology of BSMRAU in Gazipur, Bangladesh. They hope that the genetic data will help determine whether the Bangladeshi wheat-infecting strain has evolved independently from local grass-infecting fungi or was somehow introduced into the country. Professor Tofazzal Islam said "This pathogen causes a destructive disease on rice and it would be disastrous if the same situation arises now in wheat. Genomic and post-genomic research should clarify the origin of the wheat strain and guide measures for disease management. Prompt responses are needed from the scientific community and the government of Bangladesh for addressing this national crisis to ensure increasing wheat production, which is linked with future food and nutritional security of the nation." The group of scientists includes Dr Diane Saunders at The Genome Analysis Centre and John Innes Centre who developed a technique last year, known as Field Pathogenomics. To date, Field Pathogenomics has been applied to track another fungal crop disease - yellow rust. The method generates highly-specific genetic information directly from diseased wheat samples to determine the identity of the pathogen strain that's associated with an epidemic. Application of this method to wheat blast should unmask the pathogen in Bangladesh and contribute to a response plan. The recent wheat blast epidemic in Bangladesh has prompted Professor Nick Talbot, University of Exeter, to post on the wheatblast.net website a set of genetic data generated by his group from worldwide populations of the wheat and rice blast fungus. Prof Talbot said "In an emergency like this one, the community must come together to share data and compare notes. Only then, we will determine the true identity of the pathogen and put in place effective measures in a timely fashion." Professor Neil Hall, Director of The Genome Analysis Centre said: "It is critical in emerging crises like this that scientific data is rapidly generated and made available as soon as possible. Having an open-access site has already galvanized open exchange of information for the ash dieback disease. The scientific community needs to rally behind open science to respond to recurrent threats to global food security." Explore further: Rice blast research reveals details on how a fungus invades plants

The study has been performed to analyze the content of nitrates V and III as well as lead and cadmium in Brassica vegetables, both fresh and after 5-month storage in a cool storeroom. The experimental material consisted of Chinese cabbage, red and white cabbage, savoy cabbage and Brussels sprouts. The content of nitrates in the plant material was determined with the spectrophotometric method based on Griess reaction, whereas concentrations of heavy metals were assayed with the AAS method after dry mineralization. The 5-month storage period was found to decrease (by ca 65±5%) the content of nitrates V in savoy cabbage and Brussels sprouts. In turn, a ca 2-fold increase in the concentration of these compounds was determined in Chinese cabbage, and a similar tendency was observed in white cabbage. Chinese cabbage turned out to be the richest in the analyzed, undesirable elements and compounds, e.g. after storage it was characterized by an exceeded permissible level of nitrates V (750 mg kg-1 f.w.) and by the biggest, ca 10-fold, increase in concentrations of lead and cadmium. Besides, storage was observed to cause a significant increase in the content of nitrates III in the analyzed vegetables, except red cabbage, in which their content was shown to decrease by about 40%. Concentrations of nitrates III and V, Pb2+ and Cd2+ in tissues of the cabbage plants should be monitored regularly in order to prevent their excessive accumulation in the food chain of man. Source

Blair M.W.,National University of Colombia | Blair M.W.,Cornell University | Hurtado N.,National University of Colombia | Sharma P.,Agricultural University
Molecular Ecology Resources

Common bean is an important and diverse crop legume with several wild relatives that are all part of the Phaseoleae tribe of tropical crop legumes. Sequence databases have been a good source of sequences to mine for simple sequence repeats (SSRs). The objective of this research was to evaluate 14 sequence collections from common bean for SSRs and to evaluate the diversity of the polymorphic microsatellites derived from these collections. SSRs were found in 10 of the GenBank sequence collections with an average of 11.3% of sequences containing microsatellite motifs. The most common motifs were based on tri- and dinucleotides. In a marker development programme, primers were designed for 125 microsatellites which were tested on a panel of 18 common bean genotypes. The markers were named as part of the bean microsatellite-database (BMd) series, and the average polymorphism information content was 0.404 for polymorphic markers and predicted well the genepool structure of common beans and the status of the wild and cultivated accessions that were included in the study. Therefore, the BMd series of microsatellites is useful for multiple studies of genetic relatedness and as anchor markers in future mapping of wide crosses in the species. © 2012 Blackwell Publishing Ltd. Source

Acharya M.K.,Agricultural University | Kumar A.,Agricultural University
Indian Journal of Agricultural Biochemistry

Crude and different solvent (EtOAc, n-BuOH and MeOH) fractions of Cassia fistula Linn. were evaluated for their effectiveness for inhibition of conidial germination of Alternaria brassicae. MeOH fraction was most effective with a minimum inhibitory concentration of 290μg/ml. The subsequent bioassay guided fractionation and isolation of bioactive compounds of methanolic leaf extract of Cassia fistula was done on open column liquid chromatography. CSFs II and IV were effective at 2.5% dilution (16.5 and 14.75 μg/ml), whereas CSFs III, V, VI, VII and VIII were effective at 5% dilution (29.75-33 μg/ml). Methanolic crude extract and CSF I of Cassia fistula exhibited antifungal activity against A. brassicae by direct bioautography. The effect of CSFs of Cassia fistula was observed on development of Alternaria blight using detached-leaf inoculation method. Only CSF I at concentration of 80μg/ml (10% dilution) completely inhibited lesion development of A. brassicae on detached leaves of Indian mustard. TLC bioautography with A. brassicae and diagnosis with Godin reagent indicated the presence of bioactive saponins in CSF I of Cassia fistula. © 2015, Indian Society of Agricultural Biochemists. All rights reserved. Source

Intergeneric hybridization in seven diverse durum wheat genotypes was carried out using two composite varieties of Himalayan maize, viz., Bajaura Makka and Early Composite, and a wild grass, Imperata cylindrica, as pollen sources. Observations related to various haploid induction parameters put forth I. cylindrica as significantly better pollen source for haploid induction in durum wheat over maize in terms of pseudoseed formation (46.93%), embryo formation (38.06%), haploid regeneration (40.42%) and haploid formation efficiency (7.44%). The line x tester analysis revealed that both male and female genotypes had significant effects on all haploid induction parameters except haploid formation frequency in later. Among the pollen sources, I. cylindrica emerged as best combiner based on GCA values when compared with the two Himalayan maize composites. Durum wheat genotype, A-9-30-1 was recognized as the best general combiner followed by PDW 314. The present investigation proposed durum wheat × I. cylindrica as a superior technique over maize-mediated system, and its large-scale use can open a new horizon in the sphere of durum wheat doubled haploidy breeding programme. © 2015 Blackwell Verlag GmbH. Source

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