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231.
Krishna D. Joshi Attiq U. Rehman Ghullam Ullah Mian F. Nazir Mahreen Zahara Jamil Akhtar 《Journal of Crop Improvement》2017,31(4):608-627
We conducted this research because earlier research revealed that Pakistani farmers were growing 8–10-year-old wheat (Triticum aestivum L.) varieties and hence not benefitting from the recent advances in wheat breeding. Participatory varietal selection (PVS) trials were conducted to have farmers validate and include newly released wheat varieties into seed-production stream to speed up replacement of old and obsolete wheat varieties by farmer-preferred new high-yielding varieties. Fourteen new varieties recommended for irrigated and eight for rainfed environments were evaluated in this research involving smallholder farmers in food-deficit districts of Pakistan. Collaborating farmers preferred 10 varieties from the PVS trials, eight of which were germplasm from the International Maize and Wheat Improvement Center (CIMMYT) that yielded on average 5–17% more grain than local checks. Local checks used in the PVS trials in Sindh and Khyber Pakhtunkhwa were old improved varieties. Greater yield advantage from new varieties over local checks was reported from rainfed environments and areas where old local checks were used. The PVS research showed the possibility of ensuring food security of smallholder farmers as new high-yielding varieties gave an additional 0.3 –0.5 tons of grain per ha, sufficient to feed two to three persons per year. Research also revealed that innovative farmers in rainfed regions grew wheat varieties recommended for irrigated regions to identify high-yielding wheat varieties with stable performance. Feedback by farmers to wheat breeding research system was to develop even higher yielding new wheat varieties with diseases resistance to replace old and obsolete varieties to boost food security. 相似文献
232.
Shreya Srivastava Basdeo Kushwaha Jyoti Prakash Manmohan Pandey Suyash Agarwal Ravindra Kumar N. S. Nagpure Mahender Singh Paramananda Das Chaitanya Joshi Joy Krushna Jena 《Fisheries Science》2017,83(2):265-272
Magur Clarias batrachus is an indigenous catfish, commonly found in India, Nepal, Bhutan and Bangladesh. Presently, the populations of magur have declined rapidly in their natural habitat mainly due to overexploitation and habitat degradation. Understanding the population genetic structure of the species has significance in improvement of stocks and in conservation of the species. In the present study, simple sequence repeat (SSR) markers were used to differentiate the populations of magur, collected from three geographic locations. For this, a total of 31,814 SSRs were mined from the de novo assembled pooled of whole genome sequence data of C. batrachus. A bioinformatics pipeline with stringent criteria was applied to analyze the data which resulted in selection of 30,142 microsatellite loci falling in the intergenic region. Out of the 25 loci selected for primer development, 16 loci were successfully amplified and 9 loci were found to be polymorphic in this species. The average observed as well as expected heterozygosity in the loci across different stocks varied from 0.652 to 0.688 and 0.864 to 0.873, respectively. These three populations were further segregated into two clusters based on the NJ genetic distance. The Lucknow population formed one cluster, while the Bhubaneswar and Kolkata populations constituted another cluster. A comparable finding was also deduced from the STRUCTURE analyses. The results revealed significant variation among the populations of C. batrachus under study. 相似文献
233.
Vineeta Joshi M. S. Akhtar Prakash Sharma Sarika Singh Kushwaha Deepjyoti Baruah A. Ciji 《Journal Of Aquatic Food Product Technology》2017,26(7):843-855
Five species of snow trout (Schizothorax spp.) were investigated for their inherent nutritional value. Proximate composition, total fat, total cholesterol, triglyceride, fatty acids (FAs) profile, and mineral profiles were analyzed. Protein percentage in all five fish was found to be the same (P > 0.05), ranging from 15% to 18%. Moisture (75–82%) and lipid (1.5–8%) values were found to differ prominently (P < 0.05) in an inverse manner. Total fat (%), total cholesterol (mg/100 g), and triglyceride (mg/100 g) contents were found in the range of 2.73–6.54, 21.31–25.76, and 298.89–342.22, respectively. The trend of FAs in decreasing order was saturated > mono-unsaturated > polyunsaturated (n–6 > n–3). The sum of n–6 FAs value was higher than that of n–3, and the major n–6 and n–3 long chain polyunsaturated FAs (PUFAs) were arachidonic acid and docosahexaenoic acid, respectively. In most of these fish, the profile of macrominerals was phosphorus > potassium > calcium > sodium > magnesium, while the trend for microminerals was iron > zinc > copper > manganese. The snow trout species with best contribution potential to the daily requirement of n–3 long chain PUFAs was found in S. esocinus and S. niger, calcium and phosphorus in S. plagiostomus, and iron and copper in S. progastus. 相似文献
234.
Alternaria leaf spot of Ailanthus excelsa is generally considered as minor disease in India. Recently, severe disease outbreaks were recorded in the nursery of the Forest Research Institute, Dehradun, progeny trial at Jhumpa, Haryana, and in a nearby farm field. Leaf symptoms included small circular, brown, necrotic spots with a chlorotic halo. With severe infections, leaf spots coalesced and resulted in leaf blight. A small‐spored Alternaria with concatenated conidia was isolated consistently from the leaf samples with spot symptoms. Sequence analyses of the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) and the translation elongation factor 1‐alpha (tef‐1α) gene region of two fungal isolates confirmed the species as A. alternata. In detached leaf assays, both isolates produced symptoms similar to those observed on the nursery/field‐grown plants. To validate the detached leaf assay result, pathogenicity was also demonstrated on whole plants in a glasshouse. Koch's postulates were fulfilled by re‐isolating A. alternata from the inoculated leaves. This work is the first to confirm that A. alternata is associated with leaf spot and blight disease of A. excelsa in India. 相似文献
235.
Estimates of mercury emissions from individual sources and source categories are needed to understand relationships between the emissions and resulting deposition and to evaluate possible approaches to reducing those emissions. We have developed geographically-resolved estimates of annual average mercury emission rates from current anthropogenic sources in the 48 contiguous United States. These estimates were made by applying emission factors to individual facility operating data and to county-wide source activity levels. We apportioned the emissions to an Eulerian modeling grid system using point source coordinates and the fractions of county areas in each grid cell. Point sources account for about 89% of the 48-state total mercury emissions of 146.4 Mg/yr. Most of the emissions in the inventory are from combustion of mercury-containing fossil fuels and municipal waste, located primarily in the mid-Atlantic and Great Lakes states as well as in the Southeast. The major uncertainties in the emission estimates are caused by uncertainties in the emission factors used to develop the estimates. This uncertainty is likely a result of variability in the mercury content of the combusted materials and in the removal of mercury by air pollution control devices. The greatest research need to reduce uncertainties in mercury emission estimates is additional measurements to improve emission factors. 相似文献
236.
Pushpesh Joshi Mangesh P. Jadhav Kenta Shirasawa Arati Yadawad Ramesh S. Bhat 《Plant Breeding》2020,139(1):148-155
With an objective of developing the induced mutants for superior productivity and resistance to foliar diseases in peanut, two introgression lines (IL-3 and IL-4) derived from ABK genomes of peanut were subjected to gamma and sodium azide mutagenesis. Evaluation of M1, M2 and M3 generations could identify foliar disease resistant and productive mutants. Large-scale evaluation of M4 mutants during the rainy season of 2017 confirmed the superiority of 12 mutants over the respective parents and the best check (GPBD 4). The selected mutants were resistant to leaf spots (early and late) and rust diseases, and significantly more productive than the parents and GPBD 4. ddRAD-Sequencing of these mutants identified the single nucleotide polymorphisms (SNPs) when compared to their parents. The genes harbouring these structural mutations were also identified. However, no copy number variations (CNVs) were observed between the mutants and the parents. The selected mutants carried resistant-type alleles at the marker loci linked to foliar disease resistance. These promising mutants (M8) are currently under initial trials of variety development for commercial release. 相似文献
237.
238.
Genetic analysis of river,swamp and hybrid buffaloes of north‐east India throw new light on phylogeography of water buffalo (Bubalus bubalis)
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B.P. Mishra P.K. Dubey B. Prakash P. Kathiravan S. Goyal D.K. Sadana G.C. Das R.N. Goswami V. Bhasin B.K. Joshi R.S. Kataria 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):454-466
This study analysed buffaloes from north‐east India and compared their nuclear and mitochondrial DNA variations with buffaloes of mainland India, China, Mediterranean and South‐East Asia. Microsatellite genotypes of 338 buffaloes including 210 from six north‐east Indian buffalo populations and three mainland Indian breeds were analysed to evaluate their genetic structure and evolutionary relationships. Phylogenetic analysis and multidimensional scaling plot of pairwise FST revealed the clustering of all swamp‐type buffaloes of north‐east India with Lower Assamese (significantly hybrid type) buffaloes in one plane and all the mainland river buffaloes in another plane while the upper Assamese buffaloes being distinct from both these clusters. Analysis of mtDNA D‐loop region of 530‐bp length was performed on 345 sequences belonging to 23 buffalo populations from various geographical regions to establish the phylogeography of Indian water buffalo. The swamp buffaloes of north‐east India clustered with both the lineages of Chinese swamp buffalo. Multidimensional scaling display of pairwise FST derived from mitochondrial DNA data showed clustering of upper Assamese, Chilika and Mediterranean buffaloes distinctly from all the other Indian buffalo populations. Median‐joining network analysis further confirmed the distinctness and ancestral nature of these buffaloes. The study revealed north‐east region of India forming part of the wider hybrid zone of water buffalo that may probably extend from north‐east India to South‐East Asia. 相似文献
239.
In order to update the available information on the main current and future constraints on wheat production and human capacity
development, a survey covering nineteen developing countries, including major wheat producers, was conducted prior to the
2006 International Symposium on Increasing Wheat Yield Potential in Ciudad Obregon, Mexico. The results emphasize the substantial
yield losses associated with a number of critical abiotic, biotic and socioeconomic constraints, and indicate their global
prevalence. The most important constraints on wheat production are heat (affecting up to 57% of the entire wheat area in surveyed
countries), competition with weeds, and diseases (both affecting up to 55% of wheat area). Of the socioeconomic constraints
listed and evaluated by respondents, access to mechanization and availability of credit were the most often highlighted. The
most-reported infrastructural constraints were insufficient resources for field station operations. When evaluating the importance
of research partnerships to achieve national wheat program goals, respondents from all 19 countries assigned the highest importance
to partnerships with international agricultural research centers. The most desired outputs from these include development
and exchange of germplasm and assistance in capacity building and knowledge sharing. These findings confirm the anticipated
constraints and needs over the next 10–20 years and affirm the importance of international agricultural research centers in
providing support to address them. 相似文献
240.
India is the second largest producer of wheat in the world, with production hovering around 68–75 million tons for past few
years. The latest estimated demand for wheat production for the year 2020 is approximately 87.5 million tons, or about 13 million
tons more than the record production of 75 million tons harvested in crop season 1999–2000. Since 2000, India has struggled
to match that record production figure and thus faces a critical challenge in maintaining food security in the face of its
growing population. The current major challenges facing future wheat production in India are increasing heat stress; dwindling
water supplies for irrigation; a growing threat of new virulence of diseases such as wheat rusts (yellow, brown, and black)
and leaf blight; continuous adoption of rice-wheat systems on around 11 million hectares; changes in urbanization patterns,
and demand for better quality wheat. In addition, the threat posed by the new stem rust race Ug99 can not be underestimated.
The wide gap (around 2.5 t/ha) between the potential and harvested yield in the eastern Gangetic Plains also cries out for
solutions. Addressing issues related to different stresses will require harnessing genes discovered in landraces and wild
relatives following conventional as well as non-conventional approaches. For effective technology delivery in areas that suffer
from poor linkages with farmers, participatory research needs to be strengthened. The future germplasm requirements from a
dependable collaborator such as CIMMYT are largely being dictated by the above factors. 相似文献