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1.
Rupinder Pal Singh Puja Srivastava Achla Sharma N. S. Bains 《Journal of Crop Improvement》2017,31(2):183-191
With continuous outbreaks of stripe rust (Puccinia striiformis f. sp. tritici) epidemics and rapid breakdown of deployed resistance in bread wheat (Triticum aestivum L.) cultivars in North West Plains Zone (NWPZ) in India warrant knowledge and deployment of new and durable sources of resistance to stripe rust. Bread wheat cultivar PBW 343, until recently the most widely cultivated wheat variety in India, is now highly susceptible to stripe rust (score 9 on a 1–9 scale), whereas PBW 621 (score 5.05–5.65) and HD 2967 (score 5.40–6.20) show low levels of resistance. We conducted an experiment, spanning three crop seasons (2013–2014 to 2015–2016), in which parental lines, F1 and F2 populations, F3 and F4 families from two bread wheat crosses, PBW 621/PBW 343 and HD 2967/PBW 343 were generated and evaluated for stripe rust resistance against a virulent pathotype. While the F1 revealed partial dominance, the segregation pattern for stripe rust resistance in F2 and F3 showed transgressive segregation for resistance in both crosses. Chi-square analysis indicated that resistant segregants possessed two genes, one contributed by PBW 621 or HD 2967 (depending on the cross) and the other, unexpectedly but obviously, came from the most susceptible cultivar, PBW 343. Possible genetic mechanisms for this residual resistance and implications for breeding programs are discussed. 相似文献
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Cytologic studies in polyoma virus-infected mouse embryo cells 总被引：6，自引：0，他引：6
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This paper presents the simultaneous measurement of atmospheric concentration of gaseous NH3, SO2 and NO2, and particulate NH 4 + released from the mining activities of coal-mine area, Tirap colliery, Margherita (Assam). Gas samples were collected by impinger method and were analyzed colorimetrically. The vapor-phase concentration of NH3, SO2, and NO2 range between 4.7?C40.03, 1.47?C6.14, and 1.92?C2.40???g/m3. The NH 4 + concentration in PM10 and PM2.5 ranges between 0.02?C0.07 and 0.008?C0.03???g/m3, respectively. Moderately high concentrations of NH3 and SO2 on the first day were due to the coal-burning activity near the sampling site, while the low concentration of NO2 is due to less vehicle density near the sampling point. All the observed concentrations are below than those reported for the urban areas and the prescribed limit fixed by National Ambient Air Quality Standard, India. Study indicates that ammonia is the major neutralizing agent for sulfate and nitrate ions present in the particulate matter during mining activities. 相似文献
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C. A. Martínez K. Khare M. A. Elzo 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(1):54-61
The aim of this paper was to develop statistical models to estimate individual breed composition based on the previously proposed idea of regressing discrete random variables corresponding to counts of reference alleles of biallelic molecular markers located across the genome on the allele frequencies of each marker in the pure (base) breeds. Some of the existing regression‐based methods do not guarantee that estimators of breed composition will lie in the appropriate parameter space, and none of them account for uncertainty about allele frequencies in the pure breeds, that is, uncertainty about the design matrix. To overcome these limitations, we proposed two Bayesian generalized linear models. For each individual, both models assume that the counts of the reference allele at each marker locus follow independent Binomial distributions, use the logit link and pose a Dirichlet prior over the vector of regression coefficients (which corresponds to breed composition). This prior guarantees that point estimators of breed composition such as the posterior mean pertain to the appropriate space. The difference between these models is that model termed BIBI does not account for uncertainty about the design matrix, while model termed BIBI2 accounts for such an uncertainty by assigning independent Beta priors to the entries of this matrix. We implemented these models in a data set from the University of Florida's multibreed Angus‐Brahman population. Posterior means were used as point estimators of breed composition. In addition, the ordinary least squares estimator proposed by Kuehn et al. ( 2011 ) (OLSK) was also computed. BIBI and BIBI2 estimated breed composition more accurately than OLSK, and BIBI2 had a 7.69% improvement in accuracy as compared to BIBI. 相似文献
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The methanol extract of stem barks of Alianthus excelsa was partitioned with chloroform. The chloroform extract showed fungistatic and fungicidal activity against Aspergillus niger, A. fumigatus, Penicillium frequentence, P. notatum and Botrytis cinerea. 相似文献
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Singh Pushpendra Tripathi Manish Kumar Yasir Mohammad Khare Ruchi Tripathi Manoj Kumar Shrivastava Rahul 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):458-466
Plant Foods for Human Nutrition - The severe acute respiratory syndrome is a viral respiratory infection and commonly called as COVID-19, caused by severe acute respiratory syndrome coronavirus-2... 相似文献
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P. Kaushal D. R. Malaviya A. K. Roy Shalini Pathak A. Agrawal Ambica Khare S. A. Siddiqui 《Euphytica》2008,164(1):81-92
One hundred and sixty accessions representing global germplasm of guinea grass (Panicum maximum Jacq.), an important apomictic (aposporous) fodder crop, were subjected to study on reproductive diversity in apomictic seed
development utilizing ovule clearing and flow cytometric seed screen (FCSS). Single seed FCSS of selected 14 tetraploid and
five hexaploid lines demonstrated uncoupling between the three apomixis components, viz. apomeiosis, parthenogenesis and functional
endosperm development, in natural as well as experimental populations, though it differed across ploidy levels and genotypes.
Reconstruction of reproductive pathways yielded a total of eight different pathways of seed development, arising by uncoupling/recombination
between apomixis components. Amongst these, two pathways involving modifications in embryo-sac (ES) (presence of two polar
nuclei in aposporous ES that fuse prior to fertilization) and fertilization process (fusion of only one polar nucleus in a
sexual ES) have been reported for the first time. Some of the combinations, such as MI (haploids arising from parthenogenetic development of reduced egg cell), were found viable only in hexaploid background. Germplasm
lines with higher expression of individual components were also identified. These components (including autonomous endosperm
development) were also experimentally partitioned in hexaploid progenies (derived from a tetraploid parent viz. accession
IG 04-164) that showed segregation in their reproductive capacities, and are reported for the first time. Occurrence of several
apomixis recombinants (phenotypic) in guinea grass lines suggested their hybrid origin, favors a multigene model for apomixis,
with their penetrance affected by modifiers and epigenetic mechanisms, in contrast to earlier reports of single locus control.
Implications of partitioning components on apomixis research are discussed. 相似文献
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Pramod Marru Vaibhav Latane C. Puja K. Vikas Pushpendra Kumar Swati Neogi 《Fibers and Polymers》2014,15(9):1935-1940
Accelerated ageing test methodology is valid and widely accepted procedure for estimating the lifetime of isotropic homogeneous polymeric materials. However for non-isotropic and heterogeneous polymeric compounds such as glass reinforced epoxy (GRE) pipes, accelerated ageing test methodology has not been much investigated. Various standards such as ASTM D 3681, ASTM D 5365 are being used to estimate the lifetime of GRE pipes using regression analysis which is time consuming, and requires large number of test specimens and fixtures specific to pipe dimensions. Accelerated ageing test methodology can be a viable method for estimating the lifetime. The research on accelerated test methodology as a vital tool to determine the lifetime of GRE pipes has been limited. The major concern for using accelerated ageing test methodology is primarily due to the degradation kinetics of the anisotropic composite materials which may not be governed by the Arrhenius principle. The present study on the estimation of lifetime of GRE pipes in extreme acidic and alkaline medium reveals that degradation of the composite pipe follows the Arrhenius principle and the degradation mechanism can be described by first order reaction kinetics. The degradation rate, the temperature dependence of the degradation rate and lifetime of the glass reinforced epoxy pipes in extreme acidic and alkaline medium as found in the current study are presented here, along with the morphological study of aged and un-aged GRE pipes. 相似文献
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This study was attempted to assess the extent of toxicity contributed by Na+ and/or Cl? ions individually, besides their possible additive effects under NaCl using physiological and biochemical parameters. Despite the fact that most annual plants accumulate both Na+ and Cl? under saline conditions and each ion deserves equal considerations, most research has been focused on Na+ toxicity. Consequently, Cl? toxicity mechanisms including its accumulation/exclusion in plants are poorly understood. To address these issues, effects of equimolar (100 mM) concentrations of Na+, Cl? and NaCl (EC ≈ 10 dS m?1) were studied on 15-day-old seedlings of two rice cultivars, Panvel-3 (tolerant) and Sahyadri-3 (sensitive), using in vitro cultures. All three treatments induced substantial reductions in germination rate and plant growth with greater impacts under NaCl than Na+ and Cl? separately. Apparently, salt tolerance of Panvel-3 was due to its ability to exclude Na+ and Cl? from its shoots and maintaining low (<1.0) Na+/K+ ratios. Panvel-3 exhibited better vigour and membrane stability indices coupled with lower reactive oxygen species and lipid peroxidation levels, besides stimulated synthesis of proline, glycine betaine and ascorbic acid. Overall, the magnitude of toxicity was observed in NaCl > Na+ > Cl? manner. Though Cl? was relatively less toxic than its countercation, its effect cannot be totally diminished. 相似文献