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11.
12.
By enacting the Forest Rights Act 2006, the Government of India aimed to protect the rights of the forest dwellers; at the same time, it sought to involve the forest dwellers in protecting the forests. But the forest dwellers are critical of this Act, on the ground that it does not consider tribal customary laws, which are essential to protect both the forests and the rights of the forest dwellers. This paper examines the perceptions and attitudes of the dwellers of village forest and encroachers towards biodiversity conservation under the rights enshrined in the Forest Rights Act 2006. A survey was conducted in190 households in four village forests and two encroached villages under reserved forests of Sonitpur and Golaghat districts of Assam in Northeast India. The majority of the respondents were found to have positive attitudes towards environmental issues in general and protection of biodiversity loss in particular. Village-type, residents’ occupation, caste, source of fuel for cooking, educational qualifications and size of land holding were found to be significantly associated with attitudes towards biodiversity conservation. It is concluded that conducting an environmental education program and rights-holders’ monitoring system on the impact of their use of forest resources will support conservation of biodiversity.  相似文献   
13.
A study was conducted to demonstrate the comparative efficiency of acid phosphatase generated by plants or fungi towards the hydrolysis of different organic P compounds present in soil. The results revealed that acid phosphatases were most efficient in the hydrolysis of glycerophosphate followed by lecithin and phytin. The P release increased with increase in enzyme concentration. Acid phosphatase generated from fungal sources showed three times greater efficiency in the hydrolysis of phytin, two times greater efficiency in hydrolysis of lecithin than plant phosphatase. Both sources were at par in hydrolyzing glycerophosphate. The results suggest that acid phosphatase generated from plant and fungal sources is different and microbial acid phosphatase to be more efficient than that from plant sources.  相似文献   
14.
A comparison of intra‐ and extracellular acid phosphatase, alkaline phosphatase and phytase activity in six fungi is reported. A strong linear relationship between intra versus extracellular fungal acid phosphatase (R2 = 0.94), alkaline phosphatase (R2 = 0.96), and phytase (R2 = 0.97) is observed. Three‐fourth of acid phosphatase were generally present inside the fungal cells and only 25 % were released extracellularly after a three weeks period. Phytase shows the reverse trend where thirty nine times higher extracellular phytase activity was noticed than present inside the fungal cells. The extracellular enzymes are found 60 % more efficient in the hydrolysis of phytin than their intracellular counterpart but they are at par in the hydrolysis of glycerophosphate. The results clearly demonstrated that phytase types of phosphatases mostly occur outside the fungal cells whereas most of the acid phosphatase and alkaline phosphatase are located inside the cells.<?show $6#>  相似文献   
15.
The rice brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the major pests of rice across Asia. Host-plant resistance is the most ecologically acceptable means to manage this pest. A rice breeding line RP2068-18-3-5 (RP2068) derived from the land race Velluthacheera is reported to be resistant to BPH populations across India. We identified a new R gene [Bph33(t)] in this line using advanced generation RILs derived from TN1 × RP2068 cross through phenotyping at two locations and linkage analysis with 99 polymorphic SSR markers. QTL analysis through IciMapping identified at least two major QTL on chromosome 1 influencing seedling damage score in seed box screening, honey dew excretion by adults and nymphal survival. Since no BPH R gene has been reported on chromosome 1, we designate this locus as a new gene Bph33(t) which accounted for over 20% of phenotypic variance. Scanning the region for candidate gene suggested two likely candidates a leucine rich repeat (LRR) gene and a heat shock protein (HSP) coding gene. Expression profiling of the two genes in the two contrasting parents and RILs showed induction of the HSP gene (LOC_Os01g42190.1) at 6 h after infestation while LRR gene did not show such induction. It is likely that the HSP represented Bph33(t).  相似文献   
16.
A field experiment was conducted during the two consecutive kharif seasons of 2011 and 2012 on sandy-loam lateritic soil of Indian subtropics to investigate the impact of integrated nutrient management (INM) on crop productivity, nutrient use efficiency of applied nutrients and soil fertility in restoring sustainability with hybrid rice cultivation. Application of 50% recommended dose of fertilizer (RDF) + 50% recommended dose of nitrogen (RDN) through mustard oil cake (MOC) or 75% RDF + 25% RDN through MOC + biofertilizer recorded significantly higher grain and biomass yields, greater NPK removal and higher partial factor productivity of applied nutrient (PFPN) than those of the crop having 100% RDF, 100% RDN through MOC and 25% RDF + 75% RDN through MOC, which showed very poor performance. The former treatments also improved organic carbon and available NPK contents in soil in spite of greater removal of NPK by the crop. Results of study suggested integrated use of 50% RDF + 50% RDN through MOC or 75% RDF + 25% RDN through MOC + biofertilizer for increasing hybrid rice productivity, PFPN and improving soil fertility for sustainability.  相似文献   
17.
A 30-day acclimation trial was conducted using Tor putitora to elucidate its thermal tolerance, oxygen consumption, haemato-biochemical variables and selected enzymatic activities at five acclimation temperatures (AT). Juveniles of T. putitora were randomly distributed among five treatment groups (20, 23, 26, 29 and 32 ± 0.5 °C). There was a significant curvilinear increase in critical thermal maxima (CTmax) (y = ?0.0693x 2 + 1.7927x + 34.628, R 2 = 0.996) and lethal thermal maxima (LTmax) (y = ?0.1493x 2 + 2.3407x + 35.092, R 2 = 0.991) with increasing AT. The oxygen consumption rate increased significantly with increasing AT. The Q 10 values were 1.16 between 20 and 23 °C, 3.09 between 23 and 26 °C, 1.31 between 26 and 29 °C and 1.76 between 29 and 32 °C of AT. The acclimation response ratios were ranged between 0.37 and 0.59. Catalase, superoxide dismutase and ATPase activities were increased linearly in liver, gill and kidney, while brain acetylcholine esterase activity decreased linearly with increasing AT. Blood glucose remained unchanged up to AT of 26 °C and increased significantly at AT of 29 and 32 °C. Haemoglobin content was increased linearly with increasing AT. The highest WBC count was observed at 20 °C, and no significant changes found till AT of 26 °C and significantly decreased at 32 °C. Total serum protein and globulin were significantly decreased with increasing AT. Highest values were observed at 20 °C and remained consistent till 26 °C, then decreased significantly. There was no significant change in A/G ratio through the AT 20–29 °C and increased significantly at 32 °C. The increase in CTmax, LTmax and oxygen consumption rate with increasing AT may suggest that the thermal tolerance of T. putitora is dependent on its prior thermal exposure history, and it could adapt to higher AT by altering its haemato-biochemical variables.  相似文献   
18.
【目的】探讨柠檬酸铜对肉鸡生产性能、血脂指标和组织胆固醇含量的影响。【方法】采用单因子设计,将420只7日龄AA肉鸡随机分为7组,每组设3个重复,每个重复20只,公母各半。Ⅰ(对照)~Ⅶ组日粮分别添加0,50,100,150,200,250和300mg/kg柠檬酸铜,49日龄空腹称体质量,计算采食量、日增质量和料肉比。每组取6只鸡,采集血样、肝脏和胸腿肌,测定血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)、极低密度脂蛋白(VLDL-C)和高密度脂蛋白(HDL-C)及肝脏、胸腿肌胆固醇含量。【结果】与Ⅰ组(对照)相比,Ⅳ~Ⅶ组肉鸡日增质量及日采食量均显著增加(P<0.05),料肉比显著降低(P<0.05);血清TC、TG、LDL-C、VLDL-C显著降低(P<0.05),HDL-C显著升高(P<0.05);胸腿肌、肝脏中的胆固醇含量显著降低(P<0.05);Ⅰ、Ⅱ、Ⅲ及Ⅳ、Ⅴ、Ⅵ、Ⅶ组间,以上指标差异均不显著(P>0.05)。【结论】日粮中添加150~300mg/kg柠檬酸铜,具有提高肉鸡生产性能、降低肉鸡血脂和组织胆固醇含量的效果。  相似文献   
19.
Rice, with its wide geographic distribution extending from 50°N to 35°S, is expected to be the most vulnerable cultivated crop to future changing climates. Among the different abiotic stresses, extreme temperatures coinciding with critical developmental stages, increasingly frequent floods and drought spells, and worsening sea water inundation are some of the major threats to sustainable rice productivity. Following the successful implementation of molecular marker‐assisted backcrossing to introgress large‐effect QTL for submergence tolerance in rice mega varieties, rice breeding for drought, salinity and, recently, heat tolerance is employing the same approach. Although tolerance for combined submergence and salinity has been achieved, developing rice varieties with multiple tolerance for other abiotic and biotic stresses and finding the appropriate agronomic package to exploit their performance remain a challenge. The major bottleneck is the lack of unidentified large‐effect QTL for other abiotic stresses that are strongly influenced by genotype × environment (G × E) interaction. Rapid advances in the use of molecular tools, including a plethora of SNP markers, are expected to facilitate the development of major abiotic stress‐tolerant rice. In response to the actual farmer field situation, progress achieved in understanding and developing independent abiotic stress tolerance is being exploited to combine tolerances (for example, heat and drought; salinity and submergence) to address emerging environmental problems across a wide range of rice ecosystems.  相似文献   
20.
Peste des petits ruminants is a highly contagious viral disease of small ruminants making its diagnosis difficult from the similar symptoms of Rinderpest. Computer based prediction algorithms was applied to identify antigenic determinants on the nucleocapsid (N) protein of PPRV. Specificity and antigenicity of each peptide was evaluated by solid phase ELISA. Six specific peptide sequences were evaluated in multiple antigenic peptide (MAP) form and immune response was evaluated by supplementing universal T-helper epitope human IL-1beta peptide (VQGEESNDK, amino acids 163-171). Out of the six peptides 19mer sequence corresponding to 454-472 region of N protein of PPRV was found to be highly immunogenic and specific to PPRV. Evaluation of overlapping peptides differing in length for this 452-472 region, showed minimum length of 14 amino acid residues were required for the stable affinity binding of antigen-antibody. The results of immunization and indirect ELISA indicated the presence of T-helper epitope at the N-terminal end and linear B epitope at the C-terminal region of 454-472 19mer of nucleocapsid peptide of PPRV-nucleocapsid protein. The antipeptide antibodies developed against this region showed specificity to PPRV antigen differentiating it from RPV when used in indirect ELISA and western blot analysis.  相似文献   
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