排序方式: 共有19条查询结果,搜索用时 15 毫秒
11.
12.
Rashmi Upreti Joshi Ashok Kumar Singh Vijay Pratap Singh Ratna Rai Pushpesh Joshi 《Plant Breeding》2023,142(3):269-283
Global production of bananais adversely affected by abiotic stresses, namely, drought, salinity and low temperature which cause changes in morphology, anatomy, physiology and biochemical metabolism in plant. Different banana cultivars respond differently when grown in subtropical regions due to changes in temperature mainly at the time of flowering and fruiting. The subtropical regions persist cold in winter which become a major constraint for proper growth and development of banana. Only few cultivars are identified for cold tolerance. The cold tolerance is a complex phenomenon, involving numbers of interrelated metabolic pathways. With the onset of cold, growth decrease through alteration in the synthesis of metabolites which are regulated by expression of genes and their interactions. Recently, complete genome sequencing, mutation and transgenesis provided deep insight into the complex mechanism of cold tolerance in banana. In this review, efforts are made to compile the findings and to interpret the better application of technologies in understanding the cold tolerance which may assist in banana breeding. 相似文献
13.
Continuous upstream water development in the South Indian Krishna Basin has resulted in declining water availability downstream. Upstream water use is not adjusted to reflect rainfall fluctuations, and downstream farmers of the Nagarjuna Sagar irrigation project in the state of Andhra Pradesh are increasingly vulnerable to water supply shocks. Understanding the adaptive capacity of irrigated command areas to fluctuating water conditions is critical. This paper documents the wide range of adjustments adopted by managers and farmers in Nagarjuna Sagar during a period of fluctuating water availability (2000-2007). Primary and secondary data indicate managerial adjustments such as rotational and timely water supplies to meet critical water demands of standing crops. Farmers responded to changing conditions through: (a) crop diversification, (b) shifting calendars, (c) conjunctive use, (d) suspending cultivation, (e) sale of livestock, (f) out-migration, and (g) tampering with the irrigation system. Adaptive strategies are more diverse in the tail-end than in the head-end of the canal network and local adjustments are often uncoordinated and may degrade the resource base. A better understanding of the practices induced by changes in water availability is needed to refine current water allocation and management in large surface irrigation projects. Crop diversification, deficit irrigation in low-flow years, and conjunctive use are some of the practices to be promoted in a conducive agricultural environment. 相似文献
14.
Bangar Pooja Tyagi Neetu Tiwari Bhavana Kumar Sanjay Barman Paramananda Kumari Ratna Gaikwad Ambika Bhat K. V. Chaudhury Ashok 《Journal of Crop Science and Biotechnology》2021,24(2):153-165
Journal of Crop Science and Biotechnology - Mungbean [Vigna radiata (L.) R. Wilczek var. radiata] is vital grain legume having nutritional and socio-economic importance, especially in the... 相似文献
15.
Subramaniam Gopalakrishnan R. Mahender Kumar Pagidi Humayun V. Srinivas B. Ratna Kumari R. Vijayabharathi Amit Singh K. Surekha Ch. Padmavathi N. Somashekar P. Raghuveer Rao P. C. Latha L. V. Subba Rao V. R. Babu B. C. Viraktamath V. Vinod Goud N. Loganandhan Biksham Gujja Om Rupela 《Paddy and Water Environment》2014,12(1):79-87
Field experiments were conducted at DRR farm located at ICRISAT, Patancheru, in sandy clay loam soils during four seasons, Kharif 2008, Rabi 2008–2009, Kharif 2009 and Rabi 2009–2010, to investigate growth parameters, water-saving potential, root characteristics, chemical, biological, and microbial properties of rhizosphere soil, and grain yield of rice (Oryza sativa L.) by comparing the plants grown with system of rice intensification (SRI) methods, with organic or organic + inorganic fertilization, against current recommended best management practices (BMP). All the growth parameters including plant height, effective tillers (10–45 %), panicle length, dry matter, root dry weight (24–57 %), and root volume (10–66 %) were found to be significantly higher with in SRI-organic + inorganic over BMP. With SRI-organic fertilization, growth parameters showed inconsistent results; however, root dry weight (3–77 %) and root volume (31–162 %) were found significantly superior compared to BMP. Grain yield was found significantly higher in SRI-organic + inorganic (12–23 and 4–35 % in the Kharif and Rabi seasons, respectively), while with SRI-organic management, yield was found higher (4–34 %) only in the Rabi seasons compared to BMP. An average of 31 and 37 % of irrigation water were saved during Kharif and Rabi seasons, respectively, with both SRI methods of rice cultivation compared to BMP. Further, total nitrogen, organic carbon%, soil dehydrogenase, microbial biomass carbon, total bacteria, fungi, and actinomycetes were found higher in the two SRI plots in comparison to BMP. It is concluded that SRI practices create favorable conditions for beneficial soil microbes to prosper, save irrigation water, and increase grain yield. 相似文献
16.
Schnur JM Ratna BR Selinger JV Singh A Jyothi G Easwaran KR 《Science (New York, N.Y.)》1994,264(5161):945-947
Molecular self-assembly is of key importance for the rational design of advanced materials. To investigate the causal relation between molecular structure and the consequent self-assembled microstructure, self-assembled tubules of diacetylenic lipids were studied. Circular-dichroism studies give experimental evidence that the formation of tubules is driven by chiral molecular packing, in agreement with recent theories of tubules. On the basis of these results, a molecular mechanism for the formation of tubules is proposed. 相似文献
17.
Md. Akhtaruzzaman Khan Ratna Begum Rasmus Nielsen Ayoe Hoff 《Journal of the World Aquaculture Society》2021,52(1):57-72
The optimal use of resources in aquaculture is important, especially in developing countries, to obtain the highest possible outcome from the production process to support food security and poverty alleviation. Thus, within this study, the risk, efficiency, and input‐use variation in aquaculture farms in Bangladesh is investigated using a flexible stochastic frontier model with a risk and an inefficiency function. The results reveal that feed, labor, and capital have positive and significant impacts on production. In addition, an increased fingerling density and a larger farm increase the risk, whereas the use of feed and the capital invested have the opposite effect. Access to extension services has a positive effect and increases farm efficiency. An investigation of the farm size–productivity inverse relationship reveals that this phenomenon is not applicable to Bangladesh aquaculture. In general, efficient farmers are large‐scale farmers, who use a lower stocking density but a higher feeding intensity, resulting in a higher yield. On average, farmers use less labor and feed than what is optimal. To increase efficiency and reduce risk, it is recommended that more technical knowledge on optimal input use, extension service, and capital is made available to aquaculture farmers. 相似文献
18.
Yadav Ritesh Kumar Gurung Rita Dhakal Rajeev Adhikari Achyut Raj Gautam Subash Ghimire Krishna Hari Sthapit Bhuwon Ratna 《Journal of Crop Science and Biotechnology》2019,22(5):403-414
Journal of Crop Science and Biotechnology - Drawing upon consequentially growing food insecurity in mid-hills attributed to poor adoption levels inter alia inflicted by narrow range of locally... 相似文献
19.
Application of 2,4-D and 2,4,5-T at concentrations ranging from 5 to 20 mg l?1 to 5-year-old ‘Pant Lemon-1’ (Citrus limon Burm) trees reduced the vegetative growth in terms of height, spread, shoot length, number and size of the leaves in the autumn flush. Various NAA treatments (5–20 mg l?1), however, enhanced growth, but not to the extent that was observed after GA3 treatments. Application of GA3 at 10–40 mg l?1 significantly enhanced all aspects of growth, and the effects were most pronounced at 20 and 40 mg l?1. Nutritional status of the leaves showed a slight variation in relation to vegetative growth under various treatments.Some 2,4-D- and 2,4,5-T-treatments increased the fruit yield over the control, which could suggest mobilization of foods even at the expense of reduced vegetative growth. On the other hand, NAA, particularly at 10 mg l?1, increased both vegetative growth and yield, suggesting that the transport of the photosynthates from the leaves to the fruits was not at the expense of new growth extension. Due to excessive growth enhancement under higher concentrations of GA3 (20 and 40 mg l?1), comparatively fewer nutrients were translocated to the fruit “sinks”, thereby resulting in a non-significant decrease in yield. 相似文献