半干旱区黑膜覆盖对马铃薯光合特性及产量的影响

摘要

为探讨黑膜覆盖对马铃薯光合过程和产量的影响,以品种“新大坪”为试材进行试验,对比分析黑膜覆盖(PM)处理与裸地对照(CK)下马铃薯净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)、水分利用效率(WUE)及产量等变化特征.结果表明:PM处理下叶片净光合速率和气孔导度在分枝期、花序形成期及开花期均较CK增大,但不同生育期增幅差异显著,其中净光合速率在分枝期增幅最大,为63％,而气孔导度最大增幅出现在花序形成期,为38％,开花期二者增幅均最小.胞间CO2浓度PM处理在分枝期较CK降低12％,而花序形成期、开花期较CK分别提高1％、6％.蒸腾速率PM处理在分枝期、开花期较CK分别提高44％、19％,而花序形成期则下降4％.3个生育期叶片水分利用效率PM处理均高于CK,其中花序形成期提升显著.与CK相比,PM处理下的叶片光补偿点(LCP)、光饱和点(LSP)及最大净光合速率(Pmax)均有所降低,而表观量子效率(AQE)、暗呼吸速率(Rd)和产量均有所升高,其中马铃薯产量提升近3倍,增产效果明显.说明在黄土高原半干旱区,通过采用黑膜覆盖来影响马铃薯光合过程,能够显著提高马铃薯产量.%To explore the effects of black plastic film mulching on photosynthetic process and yield of potato,a field experiment of pota to named ‘ Xindaping’ was carried out.The change characteristics of net photosynthetic rate (Pn),stomatal conductance (Gs),intercellular CO2 concentration (Ci),transpiration rate (Tr),water use efficiency (WUE) and yield were comparatively analyzed between black plastic film mulching (PM) treatment and traditional planting (CK).The results show that the values of Pn and Gs under PM treatment were higher than CK at branching,inflorescence formation and flowering stages,but the increasing rates of them were significantly different.The increase of Pn under PM treatment at branching stage was more than that at other stages,and Pn at branching stage increased up to 63％,while Gs was most sensitive to PM treatment at inflorescence formation stage,and the increase of Gs was up to 38％.Meanwhile,the increase of Pn and Gs at flowering stage was smallest.Compared with CK,Ci under PM treatment at branching stage decreased by 12％,while that at inflorescence formation and flowering stages increased by 1％ and 6％,respectively.The difference of Tr between PM and CK treatments was about 44％ at branching stage,19％ at flowing stage and-4％ at inflorescence forma tion stage,respectively.The leaf water use efficiency under PM treatment increased than that of CK at branching stage,inflorescence formation stage and flowering stage,especially the increase at branching stage was significant.Compared with CK,the leaf saturation point,light compensation point and maximum net photosynthesis rate under PM treatment decreased,while the apparent quantum effi ciency,dark respiration rate and yield increased,and the yield of potato increased up to approximately 3 times,which demonstrated that the black plastic film mulching could affect photosynthetic process of potato in semi-arid region of Loess Plateau,and it could significantly increase potato yield.