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801.
Summary Tolerance of crops to soil sodicity as represented by high exchangeable sodium has been examined utilizing data from field and greenhouse studies. A piecewise linear model has been utilized for describing the crop response curves. Salt tolerance indices including the threshold ESP, slope which represents yield decline per unit increase in ESP and the value of ESP at which yield is reduced by 50% are reported for 20 crops. In respect to threshold ESP, Sesbania is the most tolerant of the crops tested followed by rice (transplanted) and wheat. These are the only three crops in which threshold ESP exceeds 15. Genotypic differences for sodicity tolerance have been examined for rice and wheat, with CSR 3 — a natural selection among the rice genotypes — and Kharchia 65 among the wheat genotypes appear to be the most tolerant. The cumulative effect of ionic imbalance and water uptake are found to be the factors governing tolerance differences. The sodicity tolerance indices reported herein represent the relative sodicity tolerance of crops to high exchangeable sodium and could be used in management and crop planning in amended sodic soils and/or management of sodic waters.Principal Scientist (Soil and Water Conservation Engg.) and Senior Scientist (Plant Physiology) respectively 相似文献
802.
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804.
The effect of various space allowances on the pituitary, adrenal and immune responses and on performance was investigated in 72 mature Holstein x Friesian beef bulls. The animals (weighing 403+/-3.5 kg) were blocked by weight and randomly assigned to two groups (familiar, F, and unfamiliar, UF) x three treatments (1.2, 2.7 and 4.2m(2) per bull; n=24 per space allowance), and housed for 83 days in 18 pens (n=4 per pen). Blood samples were collected on days -1, 0, 3, 14, 36 and 77 with respect to mixing and housing on day 0. The bulls were given exogenous adrenocorticotrophic hormone (ACTH) on day 3 and corticotrophin-releasing hormone (CRH) on days 14, 36 and 77. Basal plasma cortisol concentration was not affected (P>0.05) by mixing F and UF bulls. On day 3, basal cortisol was greater (P<0.05) in bulls housed at 1.2 than those at 2.7 and 4.2m(2) space allowances while no effect was observed in ACTH-induced plasma cortisol concentration among treatments. Following CRH administration, there was no effect (P>0.05) of treatment and treatment x time on plasma ACTH concentration. On day 14, interferon-gamma production was lower (P<0.05) in the bulls housed at 4.2 vs. 2.7 m(2) and was intermediate but not significantly different (P>0.05) for those housed at 1.2m(2). Animals housed at either space allowances had significant (P<0.05) neutrophilia, lymphopenia, eosinopenia and decreased haemoglobin on day 3 compared with day 0. The liveweight gain from days 0 to 83 was lower (P<0.05) in bulls housed at 1.2 compared with those at 2.7 and 4.2m(2). Housing bulls at 1.2m(2) space allowance had a detrimental effect on their growth and was associated with an acute rise in plasma cortisol concentration (on day 3) compared with those having space allowances of 2.7 and 4.2m(2)/bull. 相似文献
805.
Particularly in developing countries, forests provide feed for livestock in the form of fodder for stall-feeding and grazing in forest areas. Extraction of fodder resources from forests often leads to forest degradation. An attempt has been made to qualify extend of biomass extraction from forests and to compare forest fodder dependence of households in a number of forest density classes in the mountainous region of Himalayas, in Uttarakhand state in India, according to livestock owners’ perspectives. Information was obtained from a survey of livestock feed and fodder collection and utilization from 316 randomly selected households distributed across four government-defined forest density classes, namely very dense forest, moderately dense forest, open forest and scrub. Households obtained feed and fodder for livestock from three sources, i.e. forest areas, non-forest areas and local markets. Daily feed consumption per adult cattle unit varied according to source, ranging from 9.85 to 14.70 kg from forest areas, 7.40 to 11.14 kg from non-forest areas, and less than 1 kg from local markets. The dependency of households on fodder for livestock differed significantly between households located in each forest density classes. The current forest fodder extraction rate is likely to be unsustainable. Measures identified to reduce the extraction rate include greater use of alternative fodder sources and managing small patches of the natural forests adjoining dependent villages for fodder production through community participation. 相似文献
806.
D. Manohar G. Damodar Rao G. Sreenivasulu B. Senthilkumaran Aparna Dutta Gupta 《Fish physiology and biochemistry》2005,31(2-3):235-239
Vitellogenin (Vtg) is a female specific glycophospholipoprotein which can be induced both in male and female with estradiol
and xeno-estrogens. The basic theme behind the purification of vitellogenin from the fish is to understand the evolutionary
relationship and for the purification and characterization of the Vtg receptor. The male catfish, Clarias gariepinus was administrated with estradiol over a period of time for the synthesis of Vtg and the serum was collected. The Vtg was
purified from the serum using a two step chromatographic technique. The serum was passed on to DEAE-ion exchange column and
the protein was eluted using a salt gradient. The fractions containing the Vtg were pooled and passed onto a gel permeation
chromatography column and the pure protein was obtained. The molecular weight is around 200 kDa on the SDS-PAGE and around
520 kDa on the native gel electrophoresis. 相似文献
807.
Nishikant Gupta Varun Tiwari Mark Everard Melissa Savage Syed Ainul Hussain Michael A. Chadwick Jeyaraj Antony Johnson Asghar Nawab Vinod K. Belwal 《水产资源保护:海洋与淡水生态系统》2020,30(3):601-610
- The Eurasian otter (Lutra lutra), smooth‐coated otter (Lutrogale perspicillata), and Asian small‐clawed otter (Aonyx cinereus) have all been reported previously from the Indian state of Uttarakhand. However, little information is available about their current distribution in a mountainous region that is subject to increasing human‐induced stressors (such as hydropower plants, pollution, sand and boulder mining, destructive fishing techniques, poaching).
- Owing to important roles played by these otters in structuring riverine food webs (particularly taking account of their roles as top carnivores), it is critical that they receive suitable protection in the face of projected temperature rise, change in precipitation patterns, and associated river flows in this Himalayan biodiversity hotspot. This study assesses otter distribution in four rivers of Uttarakhand as a basis for informing future conservation actions.
- Field surveys were conducted (October 2018–January 2019) in reaches of the Kosi, Ramganga, Khoh, and Song rivers, supported by semi‐structured interviews (N = 379) conducted with members of local communities to collect qualitative data on views and perceptions of otter species. In addition, community‐based otter awareness camps were organized for local youths (N = 105), adults (N = 115), and schoolchildren (N = 256 covering 10 schools).
- Habitat suitability maps were created using remote‐sensing data, survey findings, and a geographic information system to provide information about priority reaches of river to be targeted for future conservation efforts.
- This study provides critical interdisciplinary baseline information to guide decision‐makers towards developing a targeted, otter‐specific conservation programme for this important Himalayan biodiversity hotspot.
- The otter conservation education programmes conducted during this study resulted in a proposal to set up a community‐based conservation initiative to monitor and report otter sightings from the area, potentially representing a way forward for achieving simultaneous otter conservation and associated ecosystem benefits for local communities.
808.
Kumar Munish Gupta Gyandeep Muhammed Nuzaiba P. R Karthik Varghese Tincy Srivastava Prem Prakash Bhushan Shashi Shukla Satya Prakash Krishna Gopal Gupta Subodh 《Aquaculture International》2022,30(4):1711-1739
Aquaculture International - The present study assessed the toxic effect of super-paramagnetic iron oxide nanoparticles (SPIONs) on haemato-immunological responses, antioxidant capacity, oxidative... 相似文献
809.
Chetan Rao Shawn Dsouza Trisha Gupta Muralidharan Manoharakrishnan Aaron Savio Lobo 《水产资源保护:海洋与淡水生态系统》2021,31(9):2402-2411
- The impacts of fisheries on several charismatic marine fauna have been a subject of global concern. Sea snakes share the same habitats as many commercially important fish species and often end up as fisheries bycatch.
- Previous studies of bycatch from India have been limited to individual reports of mortality, with little information on the regional community structure of sea snakes. This study was carried out along the Konkan coast, off the central west coast of India, between 2016 and 2018, to determine trends in the bycatch of sea snakes in coastal fisheries.
- In this study, 922 sea snakes were encountered in 916.57 gillnet haul hours and 449.16 trawlers haul hours of fishing, comprising largely of two species: beaked sea snake (Hydrophis schistosus) and spine-bellied sea snake (Hydrophis curtus) (83.05 and 16.94% respectively) which was in stark contrast to a similar study conducted in 2002–03, which recorded a dominance of H. curtus (84%) followed by H. schistosus (14%) in the same region. Both studies, however, indicated higher mortality in H. curtus than in H. schistosus in trawl nets.
- This study highlights the significant impact of non-selective fishing practices on regional assemblages of other marine organisms such as sea snakes from South Asia, which has been relatively understudied, and the potential consequences for local ecosystems.
810.
Nishikant Gupta Mark Everard Prakash Nautiyal Ishaan Kochhar Kuppusamy Sivakumar Jeyaraj Antony Johnson Atul Borgohain 《水产资源保护:海洋与淡水生态系统》2020,30(2):394-401
- Mahseer (Tor) fish species are critical components of locally adapted freshwater food webs across the Indian Himalayan biodiversity hotspot; however, multiple human stressors compounded by climate change have significantly depleted their populations over recent decades.
- Mahseer species are now considered locally vulnerable or endangered in many regions. Hydropower projects in particular have fragmented populations, impairing genetic exchange, obstructing migratory paths, and changing the structure and functioning of riverine habitats, especially of formerly fast‐flowing rivers.
- Worryingly, a literature survey and group discussions reveal that the increasing spread of non‐native fish species further compounds threats to mahseer and overall freshwater ecology. A better understanding of the current distribution, habitat requirement, and dispersal of non‐native fish is therefore essential to manage the growing threats to mahseer in the Indian Himalayan region.