干旱胁迫对塔里木盆地红枣光合特性及水分利用效率的影响

The influence of water stress on photosynthesis characteristics and water use efficiency in Jujube in Tarim Basin

以塔里木盆地滴灌枣园3龄枣树为材料,在红枣的盛果期,利用LI-6400型光合仪对不同水分处理下红枣的光合指标测定与分析。结果表明:不同水分处理下红枣净光合速率(Pn)、蒸腾速率(Tr)的日变化均表现为"单峰"曲线,Pn之间存在极显著差异,而Tr之间差异不显著;不同水分处理下光合有效辐射(PAR)、相对湿度(RH)、大气温度(Ta)、田间CO2浓度(Ca)存在极显著差异;水分利用效率(WUE)存在显著差异。从水分胁迫对红枣叶片光合特性、水分利用效率的影响综合分析,红枣对低水环境有较强的忍耐力,适应在干旱环境中生存,适宜生长的滴灌水量为320m3/667m2左右。

The diurnal variation of photosynthetic characteristics in jujube field in Tarim Basin under water stress was monitored using portable LI - 6400 photosynthesis system at the stage of full fruit. The results showed that the curves of diurnal variation in Pn （net photosynthetic rate） and Tr （transpiration rate） had single peaks; Pn, PAR （photosyn- thetically active radiation）, RH （relative humidity）, Ta （atmospheric temperature） and Ca （C02 concentration in the field） differed significantly amongst four water treatments at 0.01 level; WUE （water use efficlLency） differed significant- ly amongst four water treatments at 0.5 level, whereas there was no difference in Tr. Based on tendency of changes of photosynthesis characteristics and WUE, it was speculated that jujube could adapt to extreme arid condition, dry condi- tion, and the proper water amount of drip irrigation was about 320 m3/667m2.