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101.
The present study was conducted to study the genetic architecture of grain micronutrients (Zn, Fe and β-carotene contents), grain protein content and four yield traits in a spring wheat reference set comprising 246 genotypes. Phenotypic data on these traits recorded at two locations and the genotyping data for 17,937 SNP markers (obtained through outsourcing) were used for genome wide association study, which gave following results after Bonferroni correction using four methods: (1) single locus single trait analysis gave 136 marker-trait associations; (2) multi-locus mixed model gave 587 MTAs; (3) multi-trait mixed model gave 28 MTAs and (4) matrix-variate linear mixed model gave 33 MTAs. As many as 73 epistatic interactions were also detected. Keeping all the results in mind, nine most important MTAs were selected for biofortification. These markers were associated with three traits (GPC, GFeC and GYPP). These MTAs can be used in wheat improvement programs either using marker-assisted recurrent selection or pseudo-backcrossing method.  相似文献   
102.
Spermatogonial stem cells transplantation provides a unique approach for studying spermatogenesis. Initially developed in mice, this technique has now been extended in farm animals and provides an alternative means to preserve valuable male germ line and to produce transgenic animals. The aim of this study was to enrich type A spermatogonial cells amongst the isolated cells from goat testis, to cryopreserve these enriched populations of cells and their subsequent transplantation in unrelated recipient goats under ultrasound guidance. The cells were isolated enzymatically and enriched by differential plating and separation on discontinuous percoll gradient. Ultrasound guided injection of trypan blue dye into rete testis resulted in 20–30% filling of the seminiferous tubules. Prior to transplantation, the cells were labelled with a fluorescent dye to trace donor cells in recipient seminiferous tubules after transplantation. The fluorescent‐labelled cells were observed up to 12 weeks after transplantation.  相似文献   
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The effect of six phosphate-solubilizing fungi (PSF, two strains of Aspergillus awamori, and four of Penicillium citrinum) isolated from rhizosphere of various crops, was observed on the growth and seed production of chickpea plants (Cicer arietinum L. cv. GPF2) in pot experiments. The phosphate (P) solubilizing activity of PSF in liquid varied from 38 to 760 μg ml?1 for tricalcium phosphate (TCP) and 28–248 μg ml?1 for mussoorie rock phosphate (MRP). All PSF isolates were biocompatible and produced growth-promoting hormone, Indole acetic acid (IAA), varying in concentration from 2.5 to 9.8 μg ml?1. Of the various pot experiments carried out in green house, maximum stimulatory effect on chickpea plants growth was observed by inoculation of two A. awamori strains. This treatment resulted in 7–12% increase in shoot height, nearly three-fold increase in seed number and two-fold increase in seeds weight as compared to the control (un-inoculated) plants. Inoculation of four strains of P. citrinum exhibited lesser stimulatory effect. It showed 7% increase in shoot height, two-fold increase in seed number and 87% increase in seeds weight as compared to the control plants. However, a consortium of all the six fungal isolates showed no stimulatory effect on chickpea plants growth.  相似文献   
105.
Different stages of an Indian major carp, Cirrhina mrigala (Hamilton), i.e. hatchling, fry and fingerling, were fed diets supplemented with 3,5,3′-triiodothyronine (T3) at doses of 0, 1, 5 and 10 mg kg?1 diet for 60 days, and then reared on a hormone-free diet for 120 days to study the growth performance of fish during the treatment period (TP) and post-treatment period (PTP). Oral administration of T3 at all the stages resulted in a significantly higher specific growth rate (SGR) and better food conversion ratio (FCR) in comparison to the control group (P<0.05). However, the growth response of C. mrigala towards T3 administration appeared to be stage-specific. At the end of the experimental period of 180days (60days TP+120days PTP), the optimum dosage of T3 appeared to be 5.0 mg kg?1 diet for both hatchlings and fry, and 1.0 mg kg?1 diet for fingerlings, resulting in 62.08%, 30.22% and 13.33% higher weights than in the control group, respectively. The cost of hormone for production of 1 kg of fish was lowest in the case of hatchlings (Rs 0.54), followed by fry (Rs 7.00) and fingerlings (Rs 16.07). Hence, based on the degree of growth response of the fish towards T3 administration in addition to its economics, only incorporation of T3 in the diet of hatchlings appeared to be economical.  相似文献   
106.
Interspecific hybrids were developed between Trifolium alexandrinum cultivar Wardan × Trifolium vesiculosum and T. alexandrinum cultivar BL1 × T. vesiculosum through embryo rescue, as the crosses failed to set seed under natural conditions. Trifolium vesiculosum was used as a donor/male parent in this study as it is reported to possess tolerance to stem rot and high forage yield. Fertilization in crossed florets of the crosses was manifested from the recovery of swollen ovaries (< 7.80%) and confirmed from the presence of one degenerated ovule in most (> 93.00%) of the swollen ovaries. The hybrid embryos at various developmental stages (heart, torpedo and cotyledonary) were rescued at a frequency of 2.56% from Wardan × T. vesiculosum and 6.12% from BL1 × T. vesiculosum. Differentiation occurred only in the cotyledonary stage embryos, resulting in 17 putative interspecific hybrid plantlets. The assessment of plantlet hybridity through SSR markers (for the alleles inherited from the donor parent), micromorphological leaf traits (leaf texture and stomata) and morphological characters (plant height, leaflet length and width) confirmed production of two interspecific hybrids designated as AV1 and BV3 representing both the crosses. AV1 displayed moderate resistance and BV3 was resistant to stem rot.  相似文献   
107.
The review summarizes and evaluates recent information about the effects of anthelmintics onHaemonchus contortus. The topic is discussed under the headings effects of drugs on the absorptive surfaces, effects of drugs on metabolism, effects of drugs on the neuromuscular system, effects of drugs on developmental stages, anthelmintic efficacy, and resistant strains. Possible future lines of work are suggested in the conclusions.  相似文献   
108.
A survey was conducted in 10 districts of Northern India to record the copper deficiency in soil, fodder and serum samples. Significant deficiency of copper was observed in soil, fodder and serum samples of heifers. The copper deficient animals were listless, showed depigmentation of skin, stiff gait and were anaemic and diahorric. The purpose of the study was to evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes, vitamin and immune function which are affected by the deficiency of copper, so as to identify the parameters which can be of diagnostic importance in copper deficiency. Forty hypocuperemic heifers were selected from these areas and were randomly divided into two groups A and B. The heifers in group A were provided with mineral mixture containing copper sulphate and in group B without copper sulphate. Significant improvement (P<0.01) was observed in the haemoglobin (Hb), total leukocyte count (TLC) and total erythrocyte count (TEC) level at the 30th day of treatment in the animals of group A. Significant (P<0.01) improvement in serum. Ceruloplasmin (Cp) level was observed within 30 days of treatment, while significant (P<0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group A animals. Regarding hormones significant improvement was observed in T(3) and T(4), in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (P<0.01) improvement within 30th days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (P<0.01) improved in group A within 60 days of treatment. Similarly significant improvement in superoxide dismutase activity in RBC was observed at the 30th day, and WBC and whole blood at 60th day in group A animals. Significant improvement in liver Cu level was observed at the 30th day of treatment, while in group B the liver Cu was significantly (P<0.01) depleted at the 60th day of experimentation. Additional Cu supplementation improved growth performance significantly in group A.  相似文献   
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