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31.
Tropical Animal Health and Production - Variances and genetic parameters (heritability and correlation) were estimated for pre-weaning weights from birth to 6 weeks of age at weekly...  相似文献   
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G. R. Rout    S. Sahoo 《Plant Breeding》2007,126(4):403-409
Copper tolerance of Nicotiana tabacum L. var. Xanthi in vitro was achieved through plant regeneration from leaf explants on Murashige and Skoog's (MS) medium supplemented with 0.5 mg/l BA, 0.1–0.25 mg/l IAA and 60  μ m Cu. Tolerant organogenic calli showed more vigorous growth in medium containing 60  μ m Cu than the non-tolerant calli. Standard growth parameters such as fresh and dry weight of organogenic callus, growth tolerance index (GTI), enzyme activity (peroxidase and catalase) and copper accumulation were used as indicators of copper tolerance. The activities of peroxidase and catalase as well as estimation of protein, total amino acid and chlorophyll were greater in tolerant calli than non-tolerant ones. The GTI in the 4 weeks after the beginning of treatments yielded significant differences among the tolerant and non-tolerant organogenic callus cultures. The accumulation of copper in the tolerant calli increased significantly with an increase in copper concentration in the medium. Shoot bud regeneration was achieved in both tolerant and non-tolerant organogenic calli on MS medium containing 0.5 mg/l BA and 0.1 mg/l IAA. The tolerant regenerated shoots were rooted on half-strength basal MS medium with 60  μ m Cu for selection of tolerant clones. This study may help in the selection and characterization of Cu-tolerant lines of N. tabacum cv. 'Xanthi' for building conservation strategies and also for phytoremediation programmes.  相似文献   
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Genetic Resources and Crop Evolution - Global population growth, climate change, altered precipitation rates and cropping patterns are increasingly challenging plant scientists to improve crop...  相似文献   
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Field experiments were conducted in WTCER research farm, Mendhasal and in the farmer's field at Bishwanathpur, Orissa, India, during two crop years to assess the performance of rice as influenced by drainage at different growth stages. In the first experiment, scented rice variety CR-689-113 was tested with drainage at different growth stages in the main plot and nitrogen levels in the sub plots. In the second experiment, rice variety Swarna was investigated and drainage at different growth stages was provided under the best nitrogen level. The results revealed that drainage at the tillering stage recorded significantly higher grain yield than drainage at all other crop stages. The grain yield of rice was found to be increased by 19–22% when drainage was provided at the tillering stage for an 8–10 day period relative to that of no drainage treatment. However, drainage at the panicle initiation stage recorded the lowest grain yield. Nitrogen at 60 kg ha?1 resulted in higher grain yield. Crop growth rate and nitrogen use efficiency were found to be higher when drainage was given at the tillering stage.  相似文献   
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The persistence of fungicides on two commercial cultivars of potato was determined under field conditions at Punjab Agricultural University, Ludhiana, Punjab. Initial deposits of mancozeb on potato leaves were found to be 26.9 and 38.7 mg kg(-1), following application of ready mixture of fungicide metalaxyl 8% + mancozeb 64% (Ridomil MZ) at the rate of 1260 and 2520 g a.i. ha(-1), whereas metalaxyl residues were found to be 35.1 and 49.5 mg kg(-1), respectively. The residue level of mancozeb in potato leaves 15 days after application at single and double doze were 19.0 and 27.0 mg kg(-1) showing a loss of 29.6 and 30.3%, whereas the values for metalaxyl at single and double doze were 0.40 and 0.80 mg kg(-1) showing a loss of 98.9 and 98.4%, respectively. Residues of mancozeb and metalaxyl were not detected at 0.04 and 0.02 mg kg(-1) level in potato tubers at harvest (PHI = 53 days) at both the dosages, respectively. The persistence and dissipation of mancozeb with the application of Ridomil MZ followed similar trend as in Indofil M-45. The rate of fungicide dissipation increased with time after application in both the potato cultivars 'Kufri Chandramukhi' and 'Chipsona'. No significant difference was observed on initial deposit, persistence and dissipation of the two molecules between the two potato cultivars.  相似文献   
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Interleukin‐10 (IL‐10) is a multifunctional cytokine and plays an important role in diseases. In this study, IL‐10 gene was cloned and characterized from catla (Catla catla), which is a highly commercially important fish species in the Indian subcontinent. The result indicated that the full‐length catla IL‐10 (cIL‐10) gene had five exons and four introns with an open reading frame of 540 nucleotides encoding a polypeptide of 179 amino acids. A phylogenetic analysis of cIL‐10 gene sequence showed that cIL‐10 clustered with freshwater carps group as expected. Quantitative real‐time polymerase chain reaction analysis showed that cIL‐10 was expressed in gill, liver, kidney, intestine, skin and heart and its expression profile was up‐regulated in bacterial infection and LPS treatment. A close relationship of high cIL‐10 expression and low pro‐inflammatory cytokine IL‐1β expression was observed in the treated group of fish, which might reveal the role of cIL‐10 as an anti‐inflammatory cytokine. Mechanism of cIL‐10 induction was investigated by blocking nuclear factor (NF)‐κB ‐signalling with BAY 11‐7082 in catla kidney cell culture. Blocking NF‐κB suppressed IL‐10 induction by LPS, and thus it revealed that cIL‐10 was induced through NF‐κB signalling. These data could be helpful to understand the function of IL‐10 in fish in response to vaccinations, probiotics and various diseases.  相似文献   
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A simple and efficient protocol for direct in vitro shoot multiplication and plant regeneration was established for an important aromatic medicinal plant, Alpinia calcarata. Preinduction of rhizome segments in medium containing 8.8 μM 6-benzylamino purine (BAP) rescued the buds from dormancy in 60% of the cultures. An average of 6.2 shoots were produced from rhizomatous bud explants on Murashige and Skoog (MS) medium supplemented with 5 μM BAP, 10 μM kinetin, and 2.5 μM α-Naphthalene acetic acid (NAA). The mother cultures retained their morphogenetic potential upto four subcultures and a maximum of 1.77-fold increase in shoot multiplication was recorded after the 3rd subculture. Rooting was simultaneously induced during subculture on shoot multiplication medium eliminating an additional step for rooting induction. Rooted plantlets were successfully acclimatized in pots in the greenhouse and subsequently established in the experimental garden without any visible symptoms of wilting and necrosis. The genetic fidelity of regenerated plants was evaluated by adapting to two PCR-based DNA marker techniques, Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) which detected no variability in the in vitro multiplied plantlets of A. calcarata. This efficient method of clonal multiplication may be useful for commercial scale multiplication, and in situ and ex situ conservation of elite germplasm of A. calcarata.  相似文献   
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