【摘要】 研究了冬小麦灌浆期叶水势在喷灌和地面灌溉(对照)条件下的日变化规律,并探讨了其与农田生态因子(冠层空气温度、冠层空气相对湿度)和生理因子(气孔导度、蒸腾速率、细胞间隙CO2浓度和光合速率)之间的关系。结果表明:与对照相比,喷灌条件下叶水势日变化曲线的变化趋势没有改变,但两种灌溉方式下叶水势的大小有显著差异,喷灌条件下冬小麦叶水势明显高于地面灌溉,在一天中8∶00~18∶00期间的不同时刻,两种灌溉方式下叶水势的差异大小表现为:在灌浆前期,喷灌和地面灌溉条件下叶水势的差异以在8∶00时最大;在灌浆中期,差异以12∶00~16∶00期间最大;在灌浆后期,两种灌溉方式下一天中各时刻的差异微小,相对稳定。喷灌条件下冬小麦叶水势日变化的影响因子与地面灌溉条件下相比没有改变:灌浆前期,叶水势日变化均主要受生态因子冠层空气相对湿度、冠层空气温度的影响;灌浆中期,主要受生态因子冠层空气相对湿度、冠层空气温度和生理因子蒸腾速率的影响;灌浆后期,主要受生理因子光合速率的影响。但喷灌条件下各影响因子对叶水势的影响程度较地面灌溉条件下降低,表明喷灌条件下叶水势对影响因子变化的敏感性降低。更多还原

【Abstract】 Using Zhongyou 9507 as experiment material,the diurnal change of leaf water potential of winter wheat during grain filling stage under sprinkler irrigation and surface irrigation conditions was studied,and the relationships between leaf water potential and ecological factors(including canopy air temperature,relative humidity),physiological factors(including stomatic conductance,the transpiration rate,intercellular CO2 concentration,and the photosynthesis rate) were analyzed.The results were as follows: Compared with that under surface irrigation condition,the variability pattern of diurnal curve of leaf water potential under sprinkler irrigation condition was not significantly changed.However,the values of leaf water potential were remarkably higher under sprinkler irrigation than those under surface irrigation condition.In the early and middle grain filling stage,the highest difference of leaf water potential during 8∶00～18∶00 between sprinkler irrigation and surface irrigation conditions appeared on 8∶00 and 12∶00～16∶00,respectively,while in the late grain filling stage,the differences during 8∶00～18∶00 were not significant.Compared with those under surface irrigation condition,the major influencing factors of winter wheat’s leaf water potential under sprinkler irrigation condition were not changed.Stepwise analysis showed that canopy air temperature,relative humidity were the primary influencing factors for the leaf water potential during early grain filling stage,and canopy air temperature,relative humidity,the transpiration rate were the primary influencing factors during middle grain filling stage,while the photosynthesis rate were the primary influencing factor during late grain filling stage.The primary influencing factors’ impacting degree for the leaf water potential declined under sprinkler irrigation compared with surface irrigation,which indicated that the sensitivity of the leaf water potential to the variation of the primary influencing factors decreased.更多还原