戈壁日光温室限根栽培对油桃营养生长和光合特性的影响

Root Restriction Affects Growth and Photosynthetic Characteristics of Nectarine(Prunus persica var.nectarina Maxim.)Grown in Gobi Greenhouse

在河西走廊气候生态条件下,以油桃品种‘中农金辉’为试验材料设计135 L、225 L、360 L、576 L和1440 L(对照)限根体积(root restriction volume,RV)处理(RV135、RV225、RV360、RV576和RV1440),测定油桃树体生长、叶绿素含量、光合气体交换参数及叶绿素荧光参数,探讨限根对油桃营养生长及光合荧光特性的影响。结果表明:(1)与对照RV1440相比,RV135和RV225处理的树体干径和新梢长度均显著减小;RV360处理的树体干径显著减小,新梢长度差异不显著;RV576处理树体干径和新梢长度均差异不显著。(2)与RV1440相比,RV135和RV225处理的叶片叶绿素含量及正午(14:00)的净光合速率、蒸腾速率、气孔导度均显著降低,其胞间二氧化碳浓度显著升高,而RV360和RV576处理以上各光合参数均无显著差异。(3)与RV1440相比,限根处理油桃叶片的OJIP曲线J-I相荧光值大幅降低;正午时分的相对可变荧光差值(ΔVt)在K相小于0,且RV135和RV225的相对可变荧光差值(ΔVt)均显著降低;RV135和RV225处理的叶绿素荧光比活性参数单位反应中心吸收的光量(ABS/RC)和单位反应中心热耗散的能量(DI0/RC)较高,最大光化学效率(Fv/Fm)和PSⅡ电子传递的量子产额(φE0)较低,其综合性能参数PItotal分别比对照RV1440显著降低34.9%和27.1%,而RV360和RV576与对照相比差异不显著。研究发现,适当限根既对戈壁日光温室栽培桃树的营养生长有一定的控制作用,但又不影响其光合作用和经济产量,且其最佳限根体积是360 L,该研究结果为戈壁非耕地日光温室油桃限根栽培提供了理论依据。

Under the climatic and ecological conditions of Hexi Corridor of Gansu Province,using nectarine variety‘Zhongnong Jinhui’as experimental material,we designed the differences of root restriction volume 135 L,225 L,360 L,576 L and control 1440 L(RV135,RV225,RV360,RV576 and RV1440)and investigated the growth,chlorophyll content,photosynthetic gas exchange parameters and fluorescence parameters of nectarine tree grown in Gobi greenhouse.The effects of root restriction on vegetative growth,photosynthetic and fluorescence characteristics of nectarine were studied.The results shown that:(1)compared with the control RV1440,the stem diameter and shoots length of RV135 and RV225 treatments were significantly reduced;the stem diameter of RV360 treatment was decreased significantly,while the shoot length had no significant effects;both parameters of RV576 treatment did not shown significant difference.(2)Compared with RV1440,the chlorophyll content and net photosynthetic rate,transpiration rate and stomatal conductance of RV135 and RV225 were significantly reduced,and the intercellular CO2 concentration was significantly increased at 14:00,however,RV360 and RV576 did not show differences.(3)Compared with RV1440,the J-I phase fluorescence value of OJIP curve of nectarine leaves in root restriction treatments decreased significantly;at 14:00,the relative variable fluorescence difference(ΔVt)was less than 0 in K phase,and the relative variable fluorescence difference(ΔVt)of RV135 and RV225 was decreased significantly.The fluorescence chlorophyll specific activity parameters of RV135 and RV225 were higher in the absorption flux per reaction center(ABS/RC)and the dissipated flux per reaction center(DI0/RC),and were lower in the maximum photochemical efficiency(Fv/Fm)and the quantum yield(φE0)for electron transport(φE0)of PSⅡ.Compared with RV1440,comprehensive performance index PItotal of RV135 and RV225 were decreased by 34.9%and 27.1%,respectively,while the difference between RV135 and RV225 were not significant.It was found that proper root restriction could not only control the vegetative growth of nectarine trees,but also keep their photosynthetic characteristics and economic yield,and the optimal root restriction volume is 360 L,which provided a theoretical basis for root restriction cultivation of nectarine trees in greenhouse in gobi area.