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61.
A wild non-progenitor species from wheat (Triticum aestivum L.) tertiary gene pool, Aegilops peregrina (Hack.) Maire & Weiller accession pau3519 (UUSS), was used for introgression of leaf rust (caused by Puccinia triticina) and stripe rust (caused by Puccinia striiformis f. sp. tritici) resistance in bread wheat. The accession was crossed and backcrossed with hexaploid wheat line Chinese Spring PhI to develop two homozygous BC2F6 wheat-Ae. peregrina introgression lines (ILs), viz., IL pau16058 and IL pau16061, through induced homoeologous recombination. Homozygous lines were screened against six Puccinia triticina and two Puccinia striiformis f. sp. tritici pathotypes at the seedling stage and a mixture of prevalent pathotypes of both species at the adult plant stage. IL pau16061 showed resistance to leaf rust only, whereas IL pau16058 was resistant to both leaf and stripe rust pathotypes throughout plant life. Molecular profiling of these ILs with simple sequence repeat (SSR) markers indicated that alien introgressions were mainly terminal and very few were interstitial. Identification of linked markers with advanced genomic technologies will aid in marker-assisted pyramiding of alien genes in cultivated wheat background.  相似文献   
62.
The present study was undertaken to estimate effect of various genetic and non-genetic factors on persistency of milk production and to identify the most appropriate persistency method that fits best in our environment. In the present study, effects of different non-genetic factors, viz. year, season, days to attain peak yield, and genetic group based on the level of exotic inheritance on persistency of milk yield in crossbred cattle were studied. Data comprised of 686 first lactation daily milk yield records of crossbred cattle that were maintained at GADVASU dairy farm over a period of 25 years from 1991 to 2015 were utilized to calculate persistency coefficients by four methods, viz., Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4). Overall least squares means for persistency by Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4) were 0.896?±?0.096, 1.385?±?0.224, 187.207?±?26.398, and 0.621?±?0.098, respectively. Effect of sires was significant (P?<?0.05) on P2 and P4 methods. Effect of genetic group on all four methods was non-significant. Period of calving had significant (P?<?0.01) effect on persistency of milk yield (P2, P3, and P4 methods). Effect of season of calving on persistency of milk yield was found to be significant in all estimates obtained by the four methods. Summer and autumn calvers were most persistent whereas spring and winter calvers were least persistent for (P2, P3, and P4 methods). Persistency of milk yield was significantly (P?<?0.05) affected by days to attain peak yield in P1 and P2 methods. Maximum persistency was obtained in animals attaining peak at 41–57 days of lactation and minimum in <?41 days for Mahadevan method and ratio method. The highest heritability of persistency and minimum value of standard error was estimated as 0.275?±?0.11 for the Mahadevan method followed by the Prasad method (0.197?±?0.10) by half sib correlation method. The maximum coefficient of variation which indicates available variability was estimated as 20.788% for persistency by the Mahadevan method followed by 18.969% for the Prasad method. The highest correlation was also observed between P1 and P3 methods by Spearman’s and Pearson’s correlation for least squares breeding value of the sires. On the basis of heritability, standard error of heritability, and coefficient of variation, it can be concluded that the Mahadevan method followed by the Prasad method suits best to our environment for animals in first lactation as well as they can be utilized for effective selection for higher persistency in crossbred animals of Punjab.  相似文献   
63.
Drought is a severe abiotic stress and the major constraint on wheat (Triticum aestivum L.) productivity world wide. Deciphering the mechanisms of drought tolerance is a challenging task because of the complexity of drought responses, environmental factors and their interactions. The objective of this study was to evaluate the ability of the antioxidative defence system in imparting tolerance against drought‐induced oxidative stress and yield loss in two wheat genotypes, when subjected to long‐term field drought. Drought resulted in an increase in H2O2 accumulation and lipid peroxidation and decrease in ascorbate level in roots and leaves at different plant developmental stages. Drought‐tolerant genotype having higher antioxidative enzymes activities, and ascorbate level was superior to that of sensitive genotype in maintaining lower H2O2 content and lipid peroxidation and higher growth, yield and yield components under water deficit. Various antioxidative enzymes showed positive correlation with ascorbate and negative with H2O2 content. In developing grains, antioxidative defence response was nearly similar among both the genotypes under control condition; however, sensitive genotype failed to modulate the activities of antioxidative enzymes according to the ROS rush under field drought. Poor capacity of the antioxidative defence system in vegetative and reproductive tissues of sensitive genotype seems to be responsible, at least partly, for reduced yield potential under water deficit.  相似文献   
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65.
Plant Foods for Human Nutrition - Mahua (Madhuca longifolia) flowers are boon for the local tribes of India and have been successfully utilized traditionally for the value addition, and are very...  相似文献   
66.
Plant Foods for Human Nutrition - Sweet pepper purees (red, yellow and green) were examined for FTIR (Fourier-transform infrared spectroscopy), chemical, bioactive, color and rheological...  相似文献   
67.
68.
The immunological relationship between the Ludhiana and Hissar strains, and between the Uruli-Kanchan, Bangalore and Jaipur strains of Theileria annulata was studied. Calves were immunised against the Ludhiana strain by the infection-treatment method, against the Uruli-Kanchan strain by the infection-treatment method or by untreated low-grade infection and against the Jaipur strain by untreated low-grade infection. After 45 days, groups of immune calves and susceptible controls were challenged with 10-tick equivalent stabilates. The ensuing host responses, body temperature, swelling of the regional lymph node, appearance of schizonts in the regional lymph node and piroplasms in blood and mortality, were studied. All five strains proved very virulent and produced severe disease in susceptible calves. Immunisation with the Ludhiana, Uruli-Kanchan and Jaipur strains conferred absolute protection against severe homologous challenges. Immunisation with the Ludhiana and Uruli-Kanchan strains conferred substantial protection against heterologous challenges with the Hissar strain, and the Bangalore and Jaipur strains, respectively. Immunisation with the Uruli-Kanchan strain gave less protection against heterologous challenge with the Jaipur strain and vice versa as some of the challenged calves showed slight swelling of the regional lymph node, two had fever, all exhibited a low-grade parasitaemia and four developed anaemia.  相似文献   
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70.
A decrease in net photosynthesis (Pn) in leaves of main shoot with age ( 7 -28 days after opening) at two stages of peanut ( Arachis hypogaea L. var. M-13 ) reproductive growth (70 and 90 DAS) is reported. Pn rate decreased with advance in age of leaves, the decline was rapid during peak period of pod filling (90 DAS). Foliar application with aliphatic alcohols, maintained the chlorophyll content and enhanced PEP carboxylase activity. The present studies suggest that aliphatic alcohols enhance functional capabilities of leaf for a larger duration and hence maintain the supply of photoassimilates to the developing kernels of peanut leading to increased yield.  相似文献   
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