High temperature (HT) significantly affects crop physiological traits and reduces productivity in plants. To increase yields as well as survival of crops under HT, developing heat-tolerant plants is one of the main targets in crop breeding programs. The present study attempted to investigate the linkage of the heat tolerance between the seedling and reproductive growth stages of tomato cultivars ’Dafnis‘ and ’Minichal.’ This research was undertaken to evaluate heat tolerance under two experimental designs such as screening at seedling stage and screening from reproductive traits in greenhouses. Survival rate and physiological responses in seedlings of tomatoes with 4-5 true leaves were estimated under HT (40 °C, RH 70%, day/night, respectively) and under two control and HT greenhouse conditions (day time 28 °C and 40 °C, respectively). Heat stress significantly affected physiological–chemical (photosynthesis, electrolyte conductivity, proline) and vegetative parameters (plant height, shoot fresh weight, root fresh weight) in all tomato seedlings. The findings revealed that regardless of tomato cultivars the photosynthesis, chlorophyll, total proline and electrical conductivity parameters were varied in seedlings during the heat stress period. The heat tolerance rate of tomatoes in the seedling stage might not always be associated with reproductive parameters. HT reduced fruit parameters such as fruit weight (31.9%), fruit length (14.1%), fruit diameter (19.1%), and fruit hardness (9.1%) compared to NT under HT in heat-susceptible tomato cultivar ‘Dafnis’, while in heat-tolerant cultivar ‘Minichal’ fruit length (7.1%) and fruit diameter (12.1%) was decreased by the effects of HT, but on the contrary fruit weight (3.6%) and fruit hardness (8.3%) were increased. In conclusion, screening and selection for tomatoes should be evaluated at the vegetative and reproductive stages with consideration of reproductive parameters.
26 October 2017 in International Journal of Scientific Reports
Background: Physico-chemical change is described in case of seasonal variation. The plant became grazed in different seasonings; nitrogen, phosphorus and potassium are estimated. The aim of paper is the nutrient uptake of Desmodium triflorum due to the change in season.Methods: The sample is collected as four month interval period the grass is tolerate as low pH. N-1.67–2.04%, P- 0.34–0.61% and K-1.46–4.15%. Results: Soil had lowest concentrations of nitrogen (0.096%), phosphorus (0.004%), and potassium (0.027%) in the rainy season. The highest concentration of nitrogen (0.22%) occurred in summer season, phosphorus (0.005%) in winter and summer seasons, and potassium (0.073%) in the winter season. The carbon/nitrogen (C/N) ratio was highest (15.22:1) in summer and lowest (13.96:1) in the rainy season.Conclusions: Present study will be valuable in evaluation and management of the middle land pastures in Nepal.