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241.
Introgression of Resistance to Shattering in Brassica napus from Brassica juncea through Non-Homologous Recombination 总被引:3,自引:0,他引:3
Genetic information conffering non- shattering of siliques has been introgressed in rapeseed (Brassica napus) following; interspecific hybridization between Brassica juncea and B. napus. A reconstituted B. napus plant with complete non-dehiscence of its fruits was isolated in the BC-, generation. This plant had normal meiosis and formed 19 bivalents. Its seed fertility, however, was low (23 percent). It is suggested that the gene(s) for shattering-resistance were incorporated into a B. oleracea chromosome following allosyndetic; chromosome pairing and. segmental exchange between B. nigra and B. oleracea chromosomes in the initial interspecific AABC hybrid. 相似文献
242.
Cytoplasmic male, steriles of Brassica campestris ssp. oleifera var. brown sarson were obtained m BO generation progenies Following the repeated back-crossing of the synthetic alloploid B. oxyrrhina (2n = 18, OO) ×B. campestris. (2n = 20, AA). Alloplasmic B. campestris plants resemble B. campestris in morphology and growth pattern and do not exhibit any trait of B. oxyrrhina, However, the leave; arc mildly chlorophyll deficient in the earlier stages and turn green at late stages In the development. The reproductive parts do not show and abnormalities except that the anthers are smaller and slenderer that the normal ones and are non dehiscent, containing only sterile pollen. 相似文献
243.
A study was conducted to investigate the effects of three chemical ameliorants, namely, cycocel, limewash and potassium chloride, on stomatal frequency, leaf water potential and relative water content in brinjal ( Solanum melongena L.) plants under moisture stress conditions. Moisture stress imposed at three stages decreased stomatal frequency, the length and breadth of stomata, leaf water potential and relative water content. Of the chemical ameliorants investigated, potassium chloride performed best in terms of stomatal behaviour and leaf water potential, whereas cycocel proved best in the case of relative water content. 相似文献
244.
Interactive effect of NaCl salinity and putrescine on shoot growth, ion (Na+ , K+ and CI− ) concentration in leaf, stem and inflorescence and yield of rice (Oryza sativa L. var. GR-3) were studied. When rice plants were subjected to salt stress (12 dS/m) the extension growth and dry weight of shoot system as well as total leaf area and chlorophyll content were found markedly reduced. Analysis of leaf, stem and inflorescence of salt-stressed plants showed higher concentration of Na+ and Cl ions and lower concentration of K+ ion compared to the control. Salinization also caused a considerable fall in grain yield.
Foliar application of putrescine (10−5 M) significantly increased the growth and yield of salt-stressed plants. Putrescine treatment decreased the influx of Na+ and Cl− ions and increased the K+ level in all the tissues of salinized plants examined. Putrescine also increased the chlorophyll content in salt-stressed plants. These results suggest that exogenous application of putrescine can be used successfully to ameliorate the stress injuries caused by NaCl salinity in rice plants to a considerable extent. 相似文献
Foliar application of putrescine (10
245.
246.
Sinha D Prakash B Neog BN Baruah KK Sarmah S Rajkhowa C 《Tropical animal health and production》2011,43(2):383-387
The aim of the study was to determine the effect of feeding feed blocks containing varying proportion of urea-treated paddy
straw (UTPS) on dry matter (DM) intake (DMI), nutrient utilization and N balance in Mithun. For the purpose, four adult male
Mithun (279.5 ± 8.2 kg) were selected and offered four experimental rations viz. R1 (Napier fodder + concentrate at 60:40), R2 (UTPS + concentrate at 50:50), R3 (UTPS + concentrate at 60:40) and R4 (UTPS + concentrate at 70:30) in 4 × 4 Latin square design. The DMI % of body weight was 2.59, 2.96, 2.85 and 2.77 and the
DMI g kg−1 W0.75 was 107, 123, 118 and 115 in Mithun fed R1, R2, R3 and R4, respectively. The mean DMI was (P < 0.01) higher in animals fed R2 and R3 than R1 and R4, whereas the water intake was (P < 0.01) higher in Mithun fed R2, R3 and R4 than R1. The digestibility of DM, organic matter, crude protein, crude fibre, neutral detergent fibre and cellulose were (P < 0.05) higher in animals fed R2, R3 and R4 than R1. A positive N balance was observed in all the experimental animals, with higher (P < 0.05) values among the animals offered R2, R3 and R4 than R1. The digestible crude protein and total digestible nutrient intakes were higher (P < 0.05) in Mithun fed R2 and R3 than R1 and R4. It is concluded that the UTPS can be incorporated up to 70% to formulate the complete feed/feed block and can be used for
feeding of Mithun under complete confinement system. 相似文献
247.
Behera SP Mishra N Vilcek S Rajukumar K Nema RK Prakash A Kalaiyarasu S Dubey SC 《Comparative immunology, microbiology and infectious diseases》2011,34(2):189-196
Previous studies have shown that bovine viral diarrhoea virus type 1 (BVDV-1) subtype b is predominantly circulating in Indian cattle. During testing for exotic pestiviruses between 2007 and 2010, BVDV-2 was identified by real time RT-PCR in two of 1446 cattle blood samples originating from thirteen states of India. The genetic analysis of the isolated virus in 5′ UTR, Npro, entire structural genes (C, Erns, E1 and E2), nonstructural genes NS2-3 besides 3′ UTR demonstrated that the nucleotide and amino acid sequences showed highest similarity with BVDV-2. The entire 5′ and 3′ UTR consisted of 387 and 204 nucleotides, respectively, and an eight nucleotide repeat motif was found twice within the variable part of 3′ UTR that may be considered as a characteristic of BVDV-2. The phylogenetic analysis revealed that the cattle isolate and earlier reported goat BVDV-2 isolate fall into separate clades within BVDV-2a subtype. Antigenic typing with monoclonal antibodies verified the cattle isolate also as BVDV-2. In addition, cross-neutralization tests using antisera raised against Indian BVDV strains circulating in ruminants (cattle, sheep, goat and yak) displayed significant antigenic differences only between BVDV-1 and BVDV-2 strains. This is the first identification of BVDV-2 in Indian cattle that may have important implications for immunization strategies and molecular epidemiology of BVD. 相似文献
248.
Yogendra Prakash Singh Purnima Dhall R. M. Mathur R. K. Jain Vasanta vadde Thakur Virendra Kumar Rita Kumar Anil Kumar 《Water, air, and soil pollution》2011,218(1-4):693-701
Wastewaters from pulp and paper mills are highly toxic and around 250 xenobiotic compounds have been reported in the effluents. Tannic acid degrading bacterium, Enterobacter sp. was isolated from soil by tannic acid enrichment. This isolate was used for bioremediation of pulp and paper mill effluents. Parameters like temperature, agitation, inoculum size and treatment duration were optimized by using Qualiteck-4 software. Reduction in lignin 73% and colour up to 82% was also observed. Encouraging results were observed is reduction of COD, BOD with 16-h retention time in batch culture. 相似文献
249.
L. T. Khemani G. A. Momin P. S. Prakasa Rao P. D. Safai Prem Prakash 《Water, air, and soil pollution》1987,34(2):183-189
Chemical analysis of fog water collected by impaction in a pre-cooled chamber in Delhi has shown high concentrations of major ions. The dominant ions measured were Na+, K+, Ca+2, and Mg+2. The concentrations of acidic ions, SO4 ?2 and NO3 ?, were low. The pH values in the fog water were highly alkaline and varied from 6.4 to 7.6. The high concentrations of soil-oriented components, especially Ca+2, were more than sufficient to neutralize the small acidity in the fog water and were responsible for maintaining high alkaline pH. The pH values of fog water did not attain the low values in India (Delhi), as found in other polluted environments of Europe and the northeast United States. 相似文献
250.
Singh Mahendra Babanna Sridhar K. Kumar Dhiraj Dwivedi Ragunandhan P. Dev Inder Kumar Anil Tewari Rama Kant Chaturvedi Om Prakash Dagar Jagdish Chandra 《Agroforestry Systems》2021,95(5):977-993
Agroforestry Systems - This article presents a methodology for the valuation of agroforestry with respect to fuelwood supply for cooking and its opportunity cost. The share of fuelwood consumption... 相似文献