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351.
This study was conducted for 3 years in silty clay loam (Aquic hapludoll) associated with water tables fluctuating between 0.05 and 0.96 m depths from the surface. Tillage treatments for rice (Oryza sativa L.) were puddling by four passes of rotary puddler (PR), reduced puddling (ReP) for two passes of rotary puddler, conventional puddling (CP) and direct seeding without puddling (DSWP) in four replications. Tillage treatments for wheat (Triticum aestivum L.) were zero tillage (ZT) and conventional tillage (CT) superimposed over the plots of rice tillage treatments. Puddling caused a significant reduction in saturated hydraulic conductivity (Ks), infiltration rate (IR), and specific volume (Rv). The reduction in Ks in the PR plot at 30 days after transplanting was 27 and 46% (3-year average) higher than in the ReP and DSWP plots, respectively, but was statistically at par with that in the CP plot in the surface tilled layer. This indicates that puddling by four passes of rotary puddler and that by conventional method adopted by farmers in those conditions gives the same level of control on percolation rate. Highest rice yield (5607 kg ha−1) was obtained in the PR plot, which was statistically equal to that in the ReP plot. Wheat yield was highest (4020 kg ha−1) in the DSWP plot of rice under CT condition. Total average grain production (rice + wheat) was highest under ReP–CT treatment combination. Results thus show that quality of soil puddle obtained by half the efforts in conventional puddling was sufficient for a significantly high yield of rice with minimum deterioration of soil properties. Similarly, wheat sowing by conventional tillage in such a reduced puddling plots of rice was sufficient for a significantly high yield of wheat. 相似文献
352.
R Agarwal KVH Sastry V Tripathi R Singh R Saxena J Mohan RP Singh 《Reproduction in domestic animals》2013,48(2):278-283
In the present study, the expression profile of luteinizing hormone receptor (LHR) was investigated in the ovary, magnum and uterus and in hierarchcal follicles (F‐1, F‐2, F‐3 and F‐4) of hens subjected to moulting to establish their involvement in moulting and presence in non‐gonadal tissues. Fifty‐two layers (72 weeks) were subjected to moult for a period of 14 days. Four birds were sacrificed each time on 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12 and 14 days of moulting, and samples (ovary, magnum, uterus and hierarchal follicles) were collected aseptically for the quantitative study by real‐time polymerase chain reaction. The ovary, isthmus, uterus and magnum weight reduced significantly during induced moulting. From the 4 DOM, this reduction was drastic and reached approximately 80% of original weight in the case of ovary, isthmus and magnum and approximately 65% of original weight in the case of uterus on 14 DOM. Ovarian yellow follicles decreased gradually from 1 DOM to 4 DOM, after that no normal yellow follicle was observed in moulted bird. The number of atretic follicles increased gradually during the course of induced moulting, reaching the peak at 5 DOM. The LHR mRNA was detected in non‐gonadal tissues like magnum and uterus. The LHR expression was significantly (p < 0.05) down regulated in ovary, magnum and uterus throughout the treatment. These results indicated that LHR may have a role in reproductive tissue regression during moulting. 相似文献
353.
Tomato leaf curl disease is a severe threat to tomato production. Yield losses are generally high in the absence of effective management strategies. The disease is caused by tomato leaf curl virus (ToLCV) and is transmitted by a whitefly vector that is challenging to control. Resistance to ToLCV is absent from most cultivated tomato gene pools, although the use of resistant cultivars would provide a better control option than minimizing the vector population. Unfortunately, resistance sources based on field screening break down when virus pressure is severe. Our previous screening and virus testing of 40 tomato genotypes led to the identification of a highly resistant genotype, Solanum pimpinellifolium AAU2019, as a new source of resistance. In this study, we investigated the inheritance and genetics of resistance to ToLCV in the cross of Pusa Ruby × S. pimpinellifolium AAU2019 in F2 and BC1Ps populations, revealing a monogenic recessive gene (best-fit ratios of resistance: susceptible to be 1:3 and 0:1) responsible for ToLCV resistance in S. pimpinellifolium AAU2019. Hence, S. pimpinellifolium AAU2019 could be considered as a potential donor parent in breeding programmes to develop tomato cultivars with resistance to ToLCV. 相似文献
354.
355.
R. S. Bhatt M. K. Tripathi D. L. Verma S. A. Karim 《Journal of animal physiology and animal nutrition》2009,93(5):568-576
Influence of pre‐weaning live weight on post‐weaning growth performance was assessed on thirty‐nine 15‐day‐old Indian native lambs, randomly fed in three equal groups until 180 days of age. During pre‐weaning phase lambs were maintained under feeding regimen of grazing (C‐0; Control), grazing and ad lib creep mixture supplementation (C‐AL) or grazing, with ad lib creep mixture and milk replacer supplementation (C‐ALMR). Lambs were allowed to suckle respective dam in morning and evening till 90 days of age, and fed ad lib green leaves of Ailanthus excelsa after grazing. After weaning all lambs were maintained on grazing and ad lib finisher concentrates supplementation. Pre‐weaning performance of lambs in terms of weaning weight (17.2 kg), average daily gain (ADG; 154 g) and feed conversion ratio 3.73 was higher (p < 0.01) in C‐ALMR lambs but total gain and ADG were similar among three groups during post‐weaning phase. However, improved pre‐weaning plane of nutrition and growth rate increased (p < 0.01) finishing weight (FW) of lambs in C‐AL, 33 kg and C‐ALMR, 32 kg. Dry matter intake was significantly (p < 0.01) higher in C‐AL and C‐ALMR lambs due to combined effect of feeding. Rumen pH was lowest (p = 0.049) in C‐AL lambs. Rumen ciliate protozoa population (104/ml) decreased in C‐ALMR lambs (4.3) but increased in C‐AL lambs (50.0) more so in C‐0 Lambs (19.8). Concentrate feeding of C‐AL lamb improved nutrient digestibility. Lambs of C‐0 group consumed more DM during post‐weaning phase that improved growth performance, while nutrient digestibility was not affected by pre‐weaning nutrition. Thus, pre‐weaning nutrition has significant influence on FW, however influence of milk replacer feeding on lamb growth need further studies. 相似文献