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371.
V. K. Mishra S. K. Jha D. K. Sharma T. Damodaran Y. P. Singh 《Arid Land Research and Management》2017,31(3):253-268
An attempt has been made in the field conditions to evaluate the effect of atmospheric temperature rise on yield, ionic ratio (Na:K), and accumulation of antioxidative pigments in wheat in different growth stages under different soils. Five planting windows (PW) were classified, based on date of wheat sowing where the average temperature difference between a particular PW and PW-I varied from 1.33–4.24°C. Plant leaf area and root length density showed decreasing trend with increasing temperature. A low flag leaf water potential (?1.14?MPa) in sodic soil and high solute potential (?1.34?MPa) in saline-sodic soil was observed under PW-V, where high temperature difference (4.24°C) was recorded. The Na:K ratio was found to be highest in both straw and grain which were 1.802 and 1.126%, respectively, under saline-sodic conditions in PW-V. Proline and malondialdehyde concentration was highest under sodic conditions which varied between 2.82–2.95?mg?g?1 fresh weight (FW) and 18.38–30.18 nmol g?1 FW, respectively, under maximum temperature difference. An increase in temperature (>1°C) significantly reduced grain yield (>10%) that was negatively correlated with Na+ (r?=??0.78) but positively with K+ (r?=?+0.62) concentrations under saline-sodic conditions, however under sodic conditions, it was positively correlated with K+ (r?=?+0.63) concentration. Therefore, looking in to the climate change scenario, shifting planting window of wheat sowing may be helpful in mitigating the negative effects of heat and salt stress on wheat crop. 相似文献
372.
Ashok Mishra B. Behera A. K. Pal S. K. Mohanty B. S. Rath 《Communications in Soil Science and Plant Analysis》2017,48(12):1417-1427
Field experiments were conducted to assess the effect of nutrients management practices on yield and rainwater use efficiency of green gram (Vigna radiata), and soil fertility under moist sub-humid Alfisols at Phulbani, India, during 2005–2008. Ten treatment combinations of lime @ 10% and 20% of lime requirement (LR) @ 8.3 t ha?1, farmyard manure (FYM) @ 5 t ha?1, green leaf manure @ 5 t ha?1, and nitrogen, phosphorus, and potassium (N–P–K) (20–40–20 kg ha?1) were tested. The analysis of variance indicated that treatments differed significantly from each other in influencing yield and rainwater use efficiency. Application of lime @ 20% LR + FYM @ 5 t/ha + 40 kg P + 20 kg K ha?1 was superior with maximum mean yield of 531 kg ha?1, while lime @ 10% LR + FYM @ 5 t ha?1 + 40 kg P + 20 kg K ha?1 was the second best with 405 kg ha?1 and maintained maximum soil fertility of nutrients. The superior treatment gave maximum sustainability yield index of 67.5%, rainwater use efficiency of 0.49 kg ha?1 mm?1, improved soil pH, electrical conductivity, and soil nutrients over years. 相似文献
373.
Rajni Sinha U. S. Jaiswal M. Feza Ahmad Praveen Kumar Mishra Suparna Sinha 《Journal of plant nutrition》2017,40(13):1805-1815
Information about the nutritional status of a plant is a basic prerequisite for its adequate nutrition and is crucial to achieve high-yield productivity. Assessing the annual amount of nutrient that a tree needs to absorb in order to successfully complete a vegetative and reproductive growth is a fundamental step for developing rational fertilization in orchards. We are unaware of any report describing macro- and micronutrient dynamics in fruit at different growth stages of mango. Seven cultivars of mango (Dashehari, Langra, Mahmood Bahar, Menka, Sabri, Sundar Langra and Zardalu) were selected for the study. Different macronutrients such as nitrogen, phosphorus, potassium, calcium and magnesium (N,P, K, Ca, and Mg) and micronutrients such as iron, manganese, zinc and copper (Fe, Mn, Zn, and Cu) were analyzed at four growth stages, namelymarble stage, prestone formation stage, stone hardening stage and harvest stage. There was a significant variation in nutrient content of fruits throughout the developmental stages irrespective of cultivars. There was no definite trend of nutrient variation among cultivars but in general, most of the nutrients like N, P, K, Mg, Mn, Zn, and Cu were the highest at the marble stage, and Ca and Fe at the stone hardening stage. 相似文献
374.
Macrobrachium gangeticum (Bate) are commercially valuable prawns that are broadly distributed in the Ganga river that flows from northern to eastern India. We studied embryonic development from cleavage (blastomeres), segmentation, formation of optic vesicle, eye pigment development to larva formation, as these data are largely unknown in this species. We conducted this study using mature M. gangeticum broodstock placed in freshwater tanks. Just after spawning, females were kept in separate aerated tanks, where fecundity was estimated from the total number of eggs. Thereafter, egg samples from berried females were used to study their embryonic stages. The correlation coefficient between size and prawn weight, egg weight, egg number, body weight and egg mass of different sizes of prawns was analysed. Our results show that an increase in prawn size led to an increase in egg weight and egg number while decreases in body weight:egg mass ratio was noticed. Further results indicate that an increase in prawn weight had a positive impact on egg weight and egg number. The embryo development stages were used in this study as a tool to evaluate the development process of the prawn in a hatchery environment. 相似文献
375.