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1.
A field experiment was conducted with a bunched variety of peanut (Arachis hypogaea L.) cv. JL-24 during the summer seasons (March–June) of 1992 and 1993 in the humid tropical canal command area at the University Experimental Farm, Memari (23°1 N, 88°5 E and 21.34 m a.s.l) in West Bengal of eastern India. The soil at the site is of sandy loam (Typic Fluvaquent) texture and the area has a shallow water table. Weekly and seasonal field water balance components of actual evapotranspiration (ETa) including the capillary contribution into root zone were determined. Peanut yield and water productivity were determined for three ratios of irrigation water and cumulative pan evaporation (CPE) of 0.9, 0.7 and 0.5. Mean crop coefficients were determined for each 7-day period of growth and were related to leaf area index and growing degree-days. Average seasonal values of ETa of peanut were 434, 391 and 356 mm for the three treatments, respectively, for 115 days of growth. The total pod yield and WP were significantly higher in 0.9 IW:CPE treatment in the 1992 season. On an average, 0.9 IW:CPE treatment had 7 and 11% higher yields in 1992 and 1993, respectively, over treatments 0.7 and 0.5 IW:CPE. The maximum average Kc of 1.19 occurred about 9 weeks after sowing relative to grass reference ET (ETo).  相似文献   
2.
Rinderpest antibodies were detected by employing the fluorescent antibody test (FAT) and the immunoperoxidase test (IPT) and the results were compared with the counterimmuno electrophoresis test (CIE). FAT was found to be the most sensitive in detecting post-vaccinal antibodies followed by IPT and CIE tests.  相似文献   
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Experiments were carried out during winter–summer (January–June) season to understand the role of seed testa, cotyledons and embryonic axis in imparting dormancy of some groundnut cultivars belonging to different habit groups. Crop was harvested at four maturity stages; 90, 100, 110 and 121 days after emergence (DAE). After drying the pods in shade for 2 days, the germination of seeds with (GST) and without (GSW) testa in rolled germination towels and seeds, and embryonic axes (GEM) in culture media from individual plants of a cultivar was studied. Seed testa played an important role in imparting dormancy followed by the cotyledons, and embryonic axis. However, the nature of dormancy of embryonic axis appeared to be different from that of the testa and cotyledons. Results suggested that the dormancy in groundnut is regulated mainly by testa (a maternal tissue) in the Spanish type, but by cotyledons, and embryonic axis (both zygotic tissue) as well as testa in Virginia types. Thus the genetic control of seed dormancy in groundnut appears to be quantitative in nature.  相似文献   
5.
This paper presents the low stress mechanical properties of plain fabrics woven from cotton, bamboo viscose and cotton-bamboo viscose blended yarns. Three blends (100 % cotton, 50:50 cotton-bamboo and 100 % bamboo) were used to produce three yarn counts (20, 25 and 30 Ne). Each of these yarns was used to make fabrics with different pick densities (50, 60 and 70 picks per inch). It was found that bending rigidity, bending hysteresis, shear rigidity, shear hysteresis and compressibility is lower for bamboo fabrics as compared to those of 100 % cotton fabrics. On the other hand, extensibility, tensile energy and compressional resilience are higher for 100 % bamboo fabrics than 100 % cotton fabrics. Higher pick density increases linearity of load-elongation curve, bending rigidity, shear rigidity and compressional resilience. Shear and bending rigidities show very good correlation with the respective hysteresis values.  相似文献   
6.
Increasing production of wheat from a limited water supply can result from efficient irrigation and nutrient management. A 3‐year field experiment was conducted at the Indian Institute of Soil Science, Bhopal, to study the growth, yield, seasonal evapotranspiration (ET) and water use efficiency (WUE), and the water–yield relationship of wheat in a soybean–wheat cropping system on vertisols. Three levels of irrigation, viz. I0, no post‐sowing irrigation; I1, two irrigations [crown root initiation (CRI) and flowering stage]; and I2, three irrigations (CRI, maximum tillering and flowering stage) and three nutrient management treatments, viz. F0, control (without fertilizer/manure); F1, 100 % NPK (100–21.5–24.9 kg ha?1); and F2, 100 % NPK + farmyard manure (FYM‐10 t ha?1) were tested in a split‐plot design with three replication. It has been established (through anova ) that the year effect was rather negligible and the interaction effects of irrigation and nutrient management on the growth parameters, ET, yield components, yield and WUE were significant. Plant height, progressive leaf area index, dry matter accumulation and crop growth rate were higher in I2F2, and I2F1 and I1F2 were statistically at par. The seasonal ET increased significantly with the increase in water supply in every nutrient treatment and it was highest in I2F2 and lowest in I0F0. The highest grain yield was obtained in I2F2; and a similar yield was recorded in I3F1 and I2F2. This shows a strong interaction effect between irrigation and nutrients. Yield components, viz. number of ears m?2, number of grains ear?1 and 1000‐grain weight were significant. The higher number of ears m?2 containing greater number of grains with relatively heavier weights appeared to have contributed to the higher yield in I1F2, I2F1 and I2F2. The highest WUE obtained in I0F2 did not correspond to the highest yield and maximum ET, but a WUE of 10.43 kg ha?1 mm?1 in the I2F2 combination corresponded with the highest yield and the seasonal ET requirement was 391.8, which was 137 % greater than the water use at maximum WUE. The ET–grain yield relationship was linear, with a lowest regression slope (i.e. marginal WUE) and elasticity of water production (Ewp) in F0 and a considerably higher slope and Ewp in F1 and F2. As the Ewp is positive and close to one in 100 % NPK treatment, the scope of improving WUE and yield with only inorganic fertilizer is very little, and relatively greater scope exists in the integrated management of organic manure and inorganic fertilizer. The results suggest that integrated nutrient management (100 % NPK + FYM) in conjunction with three irrigations maximized yield of wheat with concomitant improvement in ET and WUE under limited water availability.  相似文献   
7.
The frequency, size and rate of development of cracks influence the transport of water, nutrients and gases in the soil profile and plant growth processes in Vertisols. Despite their importance, studies on characterising cracks in Vertisols of India are limited. This study attempts to evaluate the influence of different tillage practices, nutrient management and cropping systems on cracking behaviour of a Vertisol in central India. The length, depth, width, area and volume of cracks were recorded after the harvest of the wet season crops, i.e. soybean (Glycine max L.) and rice (Oryza sativa L.) from three ongoing tillage experiments with three different cropping systems, i.e. soybean–wheat (Triticum aestivum L.), soybean–linseed (Linum usitatissimum L.) and rice–wheat. The results revealed that all the crack parameters were significantly negatively correlated with the water content of the 0–15 cm soil layer and, crack width and crack volume were significantly positively correlated with the bulk density of the 0–15 cm soil layer. Gravimetric water content and bulk density of the 0–15 cm soil layer together explained 79% variation in the crack volume. The crack volume was significantly negatively correlated (r=0.86,P=0.01) with the root length density of the previous soybean crop. Rice grown under puddled condition significantly enhanced different crack parameters viz., length, depth, width, surface area and volume of the cracks over nonpuddled direct seeded rice. Sub-soiling practised in soybean under the soybean–linseed system significantly reduced the width, depth, length and surface area of cracks by 12.5, 10, 5 and 12%, respectively, over conventional tillage. No tillage practised in soybean under soybean–wheat system resulted in significant increase in width, depth and volume of the cracks but decrease in length and surface area of cracks over conventional tillage and mould board tillage practice. Application of manure reduced the magnitude of different crack parameters in soybean–linseed cropping system. Thus cracking in Vertisols can be favourably managed by the selection of proper tillage practice, cropping system and organic manure amendments.  相似文献   
8.
Natural adhesives in the feet of different arthropods and vertebrates show strong adhesion as well as excellent reusability. Whereas the hierarchical structures on the surface are known to have a substantial effect on adhesion, the role of subsurface structures such as the network of microchannels has not been studied. Inspired by these bioadhesives, we generated elastomeric layers with embedded air- or oil-filled microchannels. These adhesives showed remarkable enhancement of adhesion ( approximately 30 times), which results from the crack-arresting properties of the microchannels, together with the surface stresses caused by the capillary force. The importance of the thickness of the adhesive layer, channel diameter, interchannel spacing, and vertical position within the adhesive has been examined for developing an optimal design of this microfluidic adhesive.  相似文献   
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Here we studied the antiproliferative activity of theaflavins in cervical carcinoma HeLa cells by investigating their effects on cellular microtubules and purified goat brain tubulin. Theaflavins inhibited proliferation of HeLa cells with IC(50) value of 110 ± 2.1 μg/mL (p = < 0.01), caused cell cycle arrest at G(2)/M phase and induced apoptosis with alteration of expression of pro- and antiapoptotic proteins. Along with these antiproliferative activities, theaflavins act as microtubule depolymerizers. Theaflavins disrupted the microtubule network accompanied by alteration of cellular morphology and also decreased the polymeric tubulin mass of the cells. The polymerization of cold treated depolymerized microtubules in HeLa cells was prevented in the presence of theaflavins. In vitro polymerization of purified tubulin into microtubules was also inhibited by theaflavins with an IC(50) value of 78 ± 2.43 μg/mL (P < 0.01). Thus, disruption of cellular microtubule network of HeLa cells through microtubule depolymerization may be one of the possible mechanisms of antiproliferative activity of theaflavins.  相似文献   
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