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1.
Water scarcity is a major constraint limiting grain legume production particularly in the arid and semi‐arid tropics. Different climate models have predicted changes in rainfall distribution and frequent drought spells for the future. Although drought impedes the productivity of grain legumes at all growth stages, its occurrence during reproductive and grain development stages (terminal drought) is more critical and usually results in significant loss in grain yield. However, the extent of yield loss depends on the duration and intensity of the stress. A reduction in the rate of net photosynthesis, and poor grain set and grain development are the principal reasons for terminal drought‐induced loss in grain yield. Insight into the impact and resistance mechanism of terminal drought is required for effective crop improvement programmes aiming to improve resistance to terminal drought in grain legumes. In this article, the impact of terminal drought on leaf development and senescence, light harvesting and carbon fixation, and grain development and grain composition is discussed. The mechanisms of resistance, management options, and innovative breeding and functional genomics strategies to improve resistance to terminal drought in grain legumes are also discussed.  相似文献   
2.
Angiography of normal and diseased feet in cattle was carried out. In osteomyelitis of distal phalanx there was a narrowing of the digital artery with diminished vascular supply to the affected digit. An area of bone necrosis was found to be avascular. With overgrown hooves, narrowing of both the medial and lateral digital arteries with ill-defined laminar vessels was seen. The vascular pattern in cattle with cork screw claws was characterized by a dilated tortuous digital artery and a crowded arterial network resulting in increased vascular supply in the affected claw. Abrupt stricture of common digital artery, a crowded vascular network in the area of the middle phalanx and filling defects of terminal arches were demonstrated in animals with exostosis  相似文献   
3.
R. K. Singh  P. Gogoi 《林业研究》2012,23(2):339-344
Arbuscular mycorrhizal (AM) technology is a soil-based fertilization practice for sustainable crop productivity. We evaluated six indigenous Arbuscular mycorrhizal fungi (AMF) strains for their symbiotic response with Piper longum (long pepper), a non-timber forest product holding promise as a commercial crop for its medicinal fruits and roots. Piper saplings were raised in a 10 cm thick sand and soil mix inoculated with various AMF. Under field conditions, plants inoculated with AMF demonstrated better survival (≥80%) than non mycorrhizal plants (58%). Almost all the studied AMF strains increased the plant growth, biomass and nutrient content (N and P) over the uninoculated control. Mycorrhizal inoculation with four AMF species, viz: Glomus fasciculatum, G. clarum, G. etunicatum and G. versiforme greatly enhanced long pepper growth both in the nursery and field conditions.  相似文献   
4.
Locally available low-cost material viz. sand from the Kaliani river of Kanaighat area of Golaghat district Assam, India, was collected. The sand was fractionated and the different fractions were characterized by classical chemical analysis, powder XRD, SEM-EDXA, DTA-TGA, and by FT-IR. The chemical analysis of the size fraction of a 600–850-μm range gave more than 90% silica. This fractionated portion was modified by coating with iron oxide. Coating was carried out on the washed and separated sand by repeated treatment of Fe(NO3)3 at 110 and 600 °C, respectively. From FESEM analysis, formation of iron oxide coating over sand surface is clearly observed. The coated sand was used to remove toxic fluoride ion from the drinking water. Iron oxide-coated sand shows highly improved fluoride removal capacity compared to raw sand. The defluoridation capacity of coated sands rose up to 89% from 7% in uncoated raw sand. The effects of different parameters like adsorbent dose, contact time, temperature, initial fluoride concentration, and pH and the effects of different anions present in water along with arsenic on defluoridation capacity of the material were studied in a batch mode.  相似文献   
5.
Rice is a major agricultural crop and accounts for 40 % of the total food grain production of India. A field experiment was conducted for two successive seasons (December–June, 2012–13 and December–June, 2013–14) to assess the efficiency of rice varieties for methane (CH4) emission in relation to atmospheric carbon fixation, partitioning of carbon, and storage in the soil. Six high yielding rice varieties, Bahadur, Cauvery, Dinanath, Joymoti, Kanaklata, and Swarnabh were grown under irrigated condition. Results of the present investigation depicted differences in photosynthetic rate among the varieties accompanied by differential ability for plant biomass partitioning between the shoots and the roots. Stomatal frequency of flag leaf at panicle initiation stage was found to have strong influence on photosynthesis. Low CH4-emitting rice varieties, Bahadur and Dinanath, were found to have lower size of the xylem vessels than the high CH4-emitting rice varieties, Joymoti and Kanaklata, and found to influence the CH4 flux. Soil organic carbon storage of 0.505 Mg C ha?1 y?1 in the plough layer of soil (0–15 cm) confirmed that irrigated rice ecosystem is an effective sink of carbon. These findings suggest that selection of suitable rice varieties with higher photosynthetic efficiency and lower emission of CH4 can be a suitable biological mitigation of this greenhouse gas. Although an inverse relationship of CH4 with carbon dioxide (CO2) efflux was observed, irrigated rice ecosystem has a good potential to store substantial amount of carbon in the soil.  相似文献   
6.
Journal of Plant Diseases and Protection - Black pepper-associated endophytic Pseudomonas putida BP25 displayed volatile-mediated antagonism against rice blast fungus Magnaporthe oryzae 1637. The...  相似文献   
7.
The three-spot cichlid Amphilophus trimaculatus (Günther) is an ornamental fish known to be invasive but has not been assessed for India. The present study confirmed this non-native species’ identity using conventional and molecular methods, as well as its occurrence in the River Cauvery, the first for this species in a lotic environment outside its native range. Gut content analysis indicated a diet of predominantly insects. The river's water quality and habitat were conducive for the species’ growth and reproduction. Using the Aquatic Species Invasiveness Screening Kit, A. trimaculatus was ranked as posing a “high” risk of being invasive in the River Cauvery, with climate match analysis showing 58% similarity with the species’ native range. Vector and pathway analysis found that A. trimaculatus was introduced to India via the aquarium trade, although consignment origin remains unknown, and the most likely means of entry into the river and its tributaries was the species’ escaping from holding facilities. Subsequent dispersal and impact of the species on native fauna are discussed. The study's outcomes demonstrate the importance of using risk analysis protocols to inform management of non-native species in India, with suggestions provided for immediate and long-term measures for the species’ management.  相似文献   
8.
A series of poly(acrylonitrile-co-methylacrylate) copolymers (PAN) with varying molecular weight were synthesized by radical copolymerization using α-α′-azobisisobutyronitrile (AIBN) as initiator. These copolymers were dissolved at different concentrations in DMF and electrospun at Minimum electrospinning voltage (MEV) to correlate electrical energy required to perform the mechanical work during the spinning of the fibers. The diameters of the resultant fibers were correlated with the Berry number and average number of entanglements per chain of the spinning solution. It was observed that number of entanglements per chain, which represents the capacity of the polymer system to store elastic energy, could correlate well with the ultimate diameter of the fiber. Interestingly, the diameters of the nanofibers were found to increase linearly with increase in number of entanglements per chain with two distinct regions having transition of the slope at number of entanglement value of 3.5.  相似文献   
9.
10.
Castor (Ricinus communis L.) is an economically important plant for production of industrial oil as well as used as primary food plant for rearing of eri silkworm, Samia ricini (Donovan). The biomass yield of eight selected castor accessions were studied to find out a promising castor genotype in terms of growth and biomass yield, nutrient status, disease and pest resistant together with eri silkworm rearing performance. Among the selected accessions, Ac03 and Ac04 yielded an average of 344.70 g (±88.05) and 334.50 g (±60.62) of leaf biomass/plant respectively (mean 324.62 g; n = 8) and the yield was stable over the years (2007-10). However, in late winter, leaf blight and leaf spot disease were reported in all the castor accessions together with the infestation of hairy caterpillar (4.00-5.33%). The silkworm rearing performances were also better in Ac03 in terms of shell weight (0.50 ± 0.07 g; mean 0.42 g; n = 8), shell ratio (15.5%) and effective rate of rearing i.e. ERR (85.67). ERR of eri silkworm was influenced by biochemical compositions of leaves of different castor accessions. The weight of larvae and cocoons were significantly influenced by nitrogen and crude protein content of the foliages. Altogether, Ac03 and Ac04 castor genotypes were found to be better in terms of agronomical and yield attributing traits together with silkworm rearing performance.  相似文献   
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