家蚕来源肠球菌DNA多态性的RAPD分析   总被引：2，自引：1，他引：1  

王彦文  鲁兴萌  牟志美  V Shyam Kumar 《蚕业科学》2005,31(1):59-63

运用随机扩增多态性DNA(randomamplifiedpolymorphicDNA,RAPD)技术,对从家蚕消化道中分离的表现为生理生化特性多样性的14个肠球菌分离菌株和3个标准菌株进行了DNA多态性研究。应用筛选的8条随机引物,共扩增出625个位点,其中997%为多态性位点,表明供试菌株具有丰富的DNA多态性。对扩增结果进行聚类分析,供试菌株分为Entfaecalis、Entfaecium、Entcasseliflavus、Entavium等4个类群,与其数值鉴定结果呈相同趋势。  相似文献   

Hyperaccumulative Characteristics of Weed Species to Heavy Metals     

Shuhe Wei  Qixing Zhou  Uttam Kumar Saha 《Water, air, and soil pollution》2008,192(1-4):173-181

Phytoremediation, which mainly employs hyperaccumulators to remove heavy metals from contaminated soils, is receiving more attention world-wide. The identification of hyperaccumulators is still a key step for phytoremediation. This research is devoted to identify some plants with hyperaccumulative characteristics from weed species. In a pot culture experiment, the hyperaccumulative characteristics of 13 weed species in 11 families to Cd, Pb, Cu and Zn were examined. The result showed that Taraxacum mongolicum and Rorippa globosa indicated some Cd hyperaccumulative properties. In a sample-analysis experiment conducted in a Pb?Zn mining area, T. mongolicum and R. globosa also displayed the same hyperaccumulative characteristics. However, in a concentration gradient experiment, Cd content in shoot of T. mongolicum was not higher than 100 mg/kg (DW, dry weight), the minimum Cd concentration for a Cd-hyperaccumulator in any treatment. The concentration of Cd in the stems and leaves of R. globosa were greater than 100 mg/kg, under the conditions of the soils spiked with 25 and 50 mg/kg Cd. The Cd accumulation factors and translocation factors in the shoots of R. globosa were higher than 1 too, and the plant biomasses did not decrease significantly (p?<?0.05) compared with the control. Thus, we conclude that only R. globosa showed the whole Cd-hyperaccumulator properties, which is a Cd-hyperaccumulator.  相似文献   

Soil enzymatic activity as affected by long term application of farm yard manure and mineral fertilizer under a rainfed soybean–wheat system in N-W Himalaya   总被引：1，自引：1，他引：0  

Supradip Saha  Ved Prakash  Samaresh Kundu  Narendra Kumar  Banshi Lal Mina 《European Journal of Soil Biology》2008,44(3):309-315

Long-term experimental sites are expected to provide important information regarding soil properties as affected by management practices. This study was designed to examine the effects of continuous fertilization, and manuring on the activities of enzymes involved in mineralization of C, N, and P on a long term (33 years) field trial under sub-temperate conditions in India. Treatments at the site included application of recommended doses of nitrogen and phosphorus (NP), nitrogen and potassium (NK), nitrogen, phosphorus and potassium (NPK), farmyard manure (FYM) with N (N + FYM), FYM with NPK (NPK + FYM) and un-amended control (C). The study was done under rainfed soybean–wheat rotation. Manure application increased soil carbohydrate, dehydrogenase, acid and alkaline phosphatases, cellulase, and protease activity significantly. Urease activity was not influenced by the manure treatment and the activity was highest in controls. Both acid and alkaline phosphatase activities were negatively influenced by chemical fertilizer treatment. Almost all the enzymes studied were significantly correlated with soil C content. The results suggest that application of FYM directly or indirectly influences the enzyme activity and it in turn regulates nutrient transformation.  相似文献   

Towards collection of wild relatives of crop plants in India     

Anjula Pandey  Ajay Kumar Tomer  D. C. Bhandari  S. K. Pareek 《Genetic Resources and Crop Evolution》2008,55(2):187-202

A total of 373 species of wild relatives of crop plants representing 120 genera and 48 families were collected from different phytogeographical regions of India during a mission mode sub-project on Sustainable Management of Plant Biodiversity under National Agricultural Technology Project during 1999–2005. Significant diversity representing endemic/rare/endangered species has been discussed in this paper. The information on phytogeographical distribution, life form, economic types and assessment of threat has also been included. Thrust areas for future target collections and conservation have been discussed to serve as reference for management of genetic resources.  相似文献   

Plant growth-promoting rhizobacteria: strategies to improve abiotic stresses under sustainable agriculture     

A. Kumar  J. S. Patel  P. W. Ramteke 《Journal of plant nutrition》2019,42(11-12):1402-1415

The abiotic stresses like drought, heavy metal and salts directly or indirectly influence the global environmental pollution and decrease the agricultural productivity. The stress tolerant plant growth promoting rhizobacteria (PGPR) play an important role against the abiotic stresses in terms of enhancing the efficacy of soil, plant growth promotion (PGP). Stress tolerance PGPRs have certain specific PGP properties such as hormones synthesis, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, Indole-3-acetic acid (IAA) production, Abscisic acid (ABA) synthesis, enzymes production, nitrogen fixation, phosphorus (P) and Potassium (K) solubilization, as results which protect various crops during such stress conditions and consequently enhance crop sustainability. Efficient PGPRs isolated from various stress conditions have certainly, more useful against that particular stress. This article highlighted the isolation of various stresses tolerant PGPRs from varieties of crops under different stress conditions and their effect on varieties of crops to enhance their plant growth promotion.  相似文献   

Conservation agriculture based sustainable intensification of basmati rice-wheat system in North-West India     

Hanuman Sahay Jat  Pardeep Kumar  Jhabar Mal Sutaliya  Satish Kumar  Yadvinder Singh 《Archives of Agronomy and Soil Science》2019,65(10):1370-1386

Continuous mono-cropping of rice-wheat (RW) system with conventional tillage (CT) based management practices have led to decline in soil health, groundwater table and farmers profit in north-west India. A medium-term (4 years) farmer’s participatory strategic research trial of basmati RW system was conducted to evaluate the effects of conservation agriculture (CA) based management practices on crop yields, water productivity, profitability and soil quality. Six treatments were compared varied in the cropping system, tillage, crop establishment and residue management. CA-based management under zero-till direct seeded rice-wheat-mungbean recorded 36% higher system yield than conventional till rice-wheat system (14.91 Mg ha^?1). CA-based rice-wheat system and rice-wheat-mungbean system saved ~35% irrigation water compared to conventional RW system (2168 mm ha^?1). Total water productivity (WP_I+R) was improved by 67% with CA-based rice-wheat-mungbean system (0.90 kg grain m^?3) over the conventional system. On system basis, 42% higher net return was recorded with CA-based rice-wheat-mungbean system compared to conventional system (USD 2570 ha^?1). Mungbean integration in basmati RW system contributed 29% share in system net returns across the treatments. Soil chemical and biological properties were improved by ~40% and 150%, respectively, with CA-based management system.  相似文献   

Chemical fractions and response of cauliflower (Brassica oleracea var. botrytis) to soil applied boron     

Rajeev Padbhushan  Jajati Mandal  Sunil Kumar  Amarjeet Kumar 《Journal of plant nutrition》2019,42(5):491-500

The present study was conducted with an objective to estimate the distribution of boron (B) application in various soil fractions and their plant response for assessing the availability in the soil. Two soils (alluvial and red soil) and five levels of B (0, 0.5, 1, 2 and 3?mg B kg^?1 soil) were applied in the pot experiment, and pots were sown with cauliflower (Sabour Agrim) arranged in a completely randomized block design (CRD) with three replications. Result showed that the curd yield of cauliflower increased significantly upto 2?mg B kg^?1 soil irrespective of soils. The percent yield increase was 14.78 and 15.01 in alluvial and red soil over the control, respectively. The initial total B content was 35.88 (alluvial soil) and 15.51 (red soil) mg·kg^?1. The mean content of Fraction I, II, III, IV and V in alluvial soil was 1.11, 1.54, 0.65, 1.49, and 95.18% and in red soil was 2.68, 4.47, 6.62, 2.50, and 83.59% of the total soil B, respectively. For changes in amount of B fractions due to B applications there was significant effect on all the fractions except Fraction II. The increase in apparent B uptake was 0.43?mg B kg^?1 in alluvial soil and 0.25?mg B kg^?1 in red soil over the control (0?mg B kg^?1 soil). Regression equation of yield and B fractions showed the relationship between first four fractions to the yield. Residual fraction was found to be collinear during calculation. Overall the study predicted the bioavailability and dynamics of B in the two distinct soils.  相似文献   

Synergistic effect of bio-inoculants on yield,nodulation and nutrient uptake of chickpea (Cicer arietinum L) under rainfed conditions     

Vivek Sharma  Sandeep Sharma  Sapana Sharma  Vijay Kumar 《Journal of plant nutrition》2019,42(4):374-383

The use of efficient bio-inoculants in chickpea is the best way to increase crop productivity under rainfed conditions. To assess the combined effect of bio-inoculants on crop yield, field experiments were conducted during Rabi seasons at Research Station, Punjab Agricultural University, Ballowal Saunkhri, Punjab, India. The application of different bio-inoculants significantly improved number of pods, grain and straw yield of chickpea over the un-inoculated treatment. The combined application of Rhizobium + PSB?+?AM fungi?+?azotobactor inoculums as seed treatment with 75% of recommended phosphorus produced highest grain yield. The nodule count, nodule weight, per cent root colonization of AM fungi and different enzymes activities in soil were also highest in combined bio-inoculants treatment. The present study concluded that combined application of bio-inoculants (Rhizobium, PSB, AM fungi and azotobactor) can save 25% of recommended phosphorus by sustaining the crop yield and improving the soil health.  相似文献   

Zinc fertilization in rice-wheat cropping system under upland calcareous soil     

Ranjan Laik  Santosh Kumar Singh  Vipin Kumar  S. P. Singh  Arvind Shukla  Nidhi 《Journal of plant nutrition》2019,42(3):296-306

Zinc (Zn) fertilization is important for Zn crop biofortification as well as increasing yields, thus proper Zn recommendations for soil application is needed for Zn deficient soils. The effectiveness of Zn applications was evaluated in different combinations of rates (2.5, 5.0, 7.5, and 10.0?kg?ha^?1 per year) and frequencies (initial, alternate, and every year) in rice (Oriza sativa L.) – wheat (Triticum aestivum L.) cropping system in a Zn-deficient upland calcareous soil in the fourth year. Zn applications to rice at 7.5 and 10?kg?ha^?1 of alternate year and 5.0 to 10?kg?ha^?1 of every year had the highest rice equivalent yield as compared to no-Zn treatment. Hence, Zn application to rice at 7.5?kg?ha^?1 at alternate years is the lowest rate at which highest rice equivalent yield of rice-wheat cropping system can be obtained.  相似文献   

Micropropagation protocol for Salvadora oleoides     

Ravindra Kumar  Raoof Ahmad Najar  Kunj Bihari Gupta  Ram Gopal Saini 《林业研究》2019,(1):87-93

Salvadora oleoides Decne. is a pharmaceutically important plant. Owing to poor seed formation, viability and, germination, and to anthropogenic disturbances, this species is on the verge of extinction. A reproducible micropropagation protocol to increase the population through tissue culture has been standardized and the results are reported here. Callus tissues were initiated from young leaves and stem explants. Leaf calluses proliferated with 1.5 mg/L BAP and 0.9 mg/L 2, 4-D with additives and continuous slow proliferation up to 15 weeks on 0.5 mg/L BAP and additives with 200 mg/L activated charcoal.Direct shoot initiation took place from stem node explants after 12 days; 4–5 shoots per node were produced in 30 days. Shoot clumps elongated and grew further on MS media supplemented with 2 mg/L BAP, 0.2 mg/L NAA and additives, which generated 20–23 shoots. The elongated shoots induced tap roots with 4 mg/L NAA and200 mg/L activated charcoal in 12 days. In vitro raised plants produced secondary roots when transferred to pots containing vermiculite maintained at 28–35 ℃. The plantlets successfully acclimatised in pots containing soil in natural conditions.  相似文献