盐胁迫下水氮处理对小桐子生理特性的影响

Effects of water-nitrogen addition on Jatropha curcas L. physiological characteristics under salt stress

为研究盐胁迫条件下不同水氮处理对小桐子幼树生理特性的影响,采用3个灌水水平(灌水处理的每次灌水量分别为T1:3.2 L/株、T2:5.4 L/株、T3:9.6 L/株),4个施氮水平(NZ:0 g,NL:10 g,NM:30 g,NH:50 g),共12个处理,6次重复,进行温室小区试验.结果表明:盐胁迫下适当增加灌水量可以有效提高小桐子的净光合速率;在盐胁迫且不施氮条件下,与T1相比T2和T3能促进小桐子的光合特性、叶水势增加;适宜的土壤水氮调控有助于增加小桐子的光合作用;在盐胁迫与灌水量相同处理条件下,与NZ相比,NL,NM,NH下的小桐子的光合作用显著,且叶水势减小.与T3NH比,T3NM的净光合速率、蒸腾速率、气孔导度、叶水势分别显著提高4.98%,6.01%,9.14%,22.97%.在盐胁迫下,有利于小桐子生理特性的最优处理是T3NM.

In order to study the effects of different water-nitrogen treatments on the physiological characteristics of Jatropha curcas saplings under salt stress, three levels of irrigation were used（Irrigation volume per irrigation was T1： 3.2 L/plant, T2： 5.4 L/plant, T3： 9.6 L/plant）, and 4 nitrogen application levels（NZ： 0 g, NL： 10 g, NM： 30 g, NH： 50 g）were subjected to a greenhouse plot test. The results show that appropriately adding irrigation volume under salt stress can effectively increase the net photosynthetic rate of Jatropha curcas. Under salt stress and without nitrogen application, T2 and T3 can promote the net photosynthetic rate, transpiration rate and stomata of Jatropha curcas. Conductivity, stomatal and leaf-water potentials increase, T3 increases photosynthetic rate compared with T1 and T2. Appropriate soil water-nitrogen regulation help to increase photosynthesis of Jatropha curcas. Under the same conditions of salt stress and irrigation, by comparison with NZ, the net photosynthetic rate, transpiration rate and stomatal conductance of Jatropha curcas under NL, NM and NH increase, and the leaf-water potential decreases. Compared with T3NH, the photosynthetic rate, transpiration rate, stomatal conductance and leaf-water potential of T3NM increase significantly by 5.15%, 5.86%, 8.81%, and 23.25%, respectively. In summary, under salt stress, the optimal treatment for the physiological characteristics of Jatropha curcas is T3NM.