蓄水坑灌不同灌水上下限对苹果树叶片蒸腾日变化的影响

Effects of Different Irrigation Upper and Lower Limits on the Diurnal Variation of Transpiration of Apple Tree Leaves under Water Storage Pit Irrigation

在田间试验条件下,以10a生矮化型红富士长富二号苹果树为材料,对不同灌水上下限条件(蓄水坑灌处理T1:田间持水量的80%与60%、T2:田间持水量的90%与70%、T3:田间持水量的100%与80%;地面灌溉对照处理CK:田间持水量的80%与60%)叶片蒸腾及其影响因素的日变化进行研究,并分析叶片水分利用效率对不同灌水上下限的响应。结果表明:不同处理苹果树叶片蒸腾速率日变化特征基本一致,均为单峰曲线且峰值都出现在13∶00,日平均叶片蒸腾速率大小排序为T3>T2>CK>T1;叶片蒸腾速率主要受土壤含水率、气孔导度、胞间CO2浓度、大气温度、叶面温度的影响。叶片水分利用效率日变化呈先降低后升高的趋势,日平均叶片水分利用效率大小排序为T1>T2>T3>CK,且T1与T2、T3、CK都有显著性差异。综合对比知,T1的节水效果最显著。

Under field conditions,the experiment,with 10 years growth of dwarfing ChangfuⅡtype Red Fuji apple trees treated as materials,the effect of different irrigation upper and lower limits,including water storage pit irrigation treatment T1,80%and 60%of field water capacity,T2,90%and 70%of field water capacity,T3,100%and 80%of field water capacity,and control treatment of ground irrigation,CK,80%and 60%of field water capacity,on the diurnal variation of transpiration and its influencing factors of apple tree leaves were studied,and the response of leaf water use efficiency to different upper and lower irrigation levels was analyzed.The results show that:the diurnal variation of transpiration rate of apple leaves under different treatments is basically consistent,both of which are unimodal curves and the peak values appear at 13∶00.The average daily transpiration rate is ranked as T3>T2>CK>T1.Leaf transpiration rate is mainly affected by soil moisture content,stomatal conductance,intercellular CO2 concentration,atmospheric temperature and leaf surface temperature.The diurnal variation of water use efficiency of leaves shows a trend of first decreasing and then increasing.The average daily water use efficiency of leaves is ranked as T1>T2>T3>CK,and there are significant differences between T1,T2,T3 and CK.According to the comprehensive comparison,T1 has the most significant water-saving effect.