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Bibek Yumnam Yadvendradev V. Jhala Qamar Qureshi Jesus E. Maldonado Rajesh Gopal Swati Saini Y. Srinivas Robert C. Fleischer 《PloS one》2014,9(11)
Even with global support for tiger (Panthera tigris) conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km2 of forest habitat was found to be only 21,290 km2. After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (F
ST) between populations were better explained by modeled linkage costs (r>0.5, p<0.05) compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should provide legal status to corridors, use smart green infrastructure to mitigate development impacts, and restore habitats where connectivity has been lost. 相似文献
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V. Johnson M. Singh V. S. Saini V. R. Sista N. K. Yadav 《World journal of microbiology & biotechnology》1992,8(4):382-384
Maximum lipid production (66% w/w dry wt) inRhodotorula glutinis IIP-30 utilizing glucose in a fed-batch fermentation under N-limiting conditions at 30°C, was at pH 4. At pH 3, 5 and 6, the lipid contents were 12%, 48% and 44%, respectively. There was only a small change in the fatty acid profile over the pH range examined, although the ergosterol content decreased by a third as the pH increased. 相似文献
5.
Eight of 104 fast-growing strains of Rhizobium sp. ( Sesbania ) tested possessed a hydrogen recycling system. Depression of uptake hydrogenase occurred in poor as well as in rich carbon media. A statistically significant increase (> 22%) in total plant nitrogen content and dry matter yield was observed by the inoculation of hup + strains over hup - strains. 相似文献
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A linear relationship was obtained between the logarithm of count rate and absorber’s (Aluminum foil and leaf) effective thickness in the range of 4.25 to 18.00 mg cm?2. Also relative water content (RWC) and absorber effective thickness was linearly related (Y = ?89.80 + + 15.84 X, and r = 0.99). From these relationships it was possible to determine the RWC of a rice leaf simply by measuring the radiation intensity of fresh, fully turgid and completely dry leaf by beta ray gauge technique without the added necessity of determining the mass of the leaf. 相似文献
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Glabrachalcone, a new chromenochalcone has been isolated along with a known chromenochalcone from an ethanolic extract of the seed oil of Pongamia glabra. The structure of glabrachalcone has been established as 2′-hydroxy-2,4,5-trimethoxy-6″,6″-dimethylchromeno(4′,3′:2″,3″)chalcone on the basis of spectral evidence and was confirmed by synthesis. 相似文献
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G. R. Saini 《Plant and Soil》1971,34(1):159-164
Summary A drainage experiment with a tank model was conducted in the laboratory to evaluate the effect of gypsum and limestone on
water movement and salt removal from recently flooded coastal alluvial soils. Equipotential lines, out-flow rates and the
amount of sodium and chloride ions removed indicated that gypsum was a superior amendment to limestone.
Contribution from Research Station, Canada Department of Agriculture, Fredericton, New Brunswick, Canada. 相似文献
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The origin of serum alkaline phosphatase in the rat 总被引:1,自引:0,他引:1
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Total peroxidase, NADH-peroxidase, ascorbate peroxidase, superoxide dismutase, and catalase activities were measured in tobacco (Nicotiana tabacum) leaves and in regenerating and nonregenerating protoplasts isolated from the same tissue and cultured for 2 weeks. The specific ranges of H2O2 concentration at which the enzymes scavenging the active forms of oxygen may efficiently operate and the activities of those enzymes were determined in an extract from tobacco leaves and in dividing and nondividing tobacco mesophyll protoplasts. The overall H2O2-scavenging enzyme activities were similar in both protoplast populations during the 2 to 3 d of culture. After 3 d, the regenerating protoplasts started to divide and both the antioxidant enzyme activities and the total peroxidase activity increased; in contrast, the viability and the H2O2-scavenging enzyme activities in nonregenerating protoplasts dramatically decreased. Surprisingly, the regenerative potentiality in dividing protoplasts was specifically correlated with a higher NADH-peroxidase activity, which resulted in a net H2O2 accumulation in the cells. Light, which causes the accumulation of active forms of oxygen in photosynthetic organelles, also stimulated catalase and ascorbate peroxidase activities in dividing protoplasts. We suggest that the localization of H2O2 rather than its absolute concentration might be responsible for oxidative stress and that controlled amounts of H2O2 are necessary to allow proper cell-wall reconstitution and the consequent cell division. 相似文献