间作隔根对花生和棉花叶片光合特性的影响

Effect of Different Root Isolation Methods on the Photosynthesis Characteristics of Peanut and Cotton Leaves

为明确地上与地下部种间相互作用对作物光合特性的影响,通过设置三种不同隔根方式,研究不同根系分隔、不同边行对花生及棉花功能叶片SPAD值、净光合速率、气孔导度、胞间CO2浓度和蒸腾速率的影响。结果表明:花生/棉花间作降低了花生功能叶片叶绿素含量,且越靠近棉花行降低越多。在生育后期,与单作相比,间作花生的叶绿素含量降低4.62%~7.71%,尼龙网隔根与塑料布隔根处理较无隔根处理分别降低4.36%、3.24%;花生/棉花间作增加了棉花功能叶片SPAD值,越靠近花生行增加越多,隔根降低了棉花叶片叶绿素SPAD值。与单作相比,间作花生的净光合速率降低了5.39%~10.12%,尼龙网与塑料布隔根处理的花生净光合速率与无隔根处理相比分别降低1.18%~5.00%、1.02%~3.36%,各处理表现为单作花生(hd)>花生间作不隔根(w)>间作塑料布隔根(s)>间作尼龙网隔根(n)。各处理内部各行随着遮荫程度的减小,净光合速率增加,表现为边1行<边2行<边3行。间作增加了棉花功能叶净光合速率、气孔导度、蒸腾速率,降低了胞间CO2浓度,间作棉花的净光合速率较单作增加24.42%~51.93%。塑料布隔根处理消除了花生和棉花根系的相互作用,间作棉花的净光合速率略有降低,但仍高于单作,与不隔根处理相比降低了14.67%~17.55%,各处理表现为间作不隔根(w)>间作尼龙网隔根(n)>间作塑料布隔根(s)>单作棉花(md)。间作不同隔根处理间具有明显的边行优势,表现为边1行>边2行,且根系间的相互作用有利于提高作物的光合能力。

In order to determine the effect of the interaction between above and underground species on the photosynthesis characteristics of crops,three different isolation methods were set up to study the effects of different root isolation and different side rows on SPAD values,net photosynthesis rate,stomatal conductance,intercellular CO2 concentration and transpiration rate of functional leaves of peanut and cotton.The results showed that the leaf chlorophyll content of peanut function leaves was significantly reduced through intercropping pattern,and the closer to cotton line,the greater reduction was detected.In the later growth stage,the chlorophyll content of peanutwas decreased by 4.62%~7.71%comparing with monocultured peanut,and the SPAD value of peanut leaves of mesh barrier and plastic sheet barrier was 4.36%,3.24%lower than the treatment without root barrier,respectively.The intercropping increased SPAD value of cotton functional leaves,and the closer to the peanut line,the greater the induction was detected,the root barrier reduced the SPAD value of cotton leaves.The net photosynthesis rate of intercropped peanut were decreased by 5.39%~10.12%comparing with monocultured peanut,and the net photosynthesis rate of peanuts treated with plastic sheet barrier were decreased by 1.18%~5.00%,1.02%~3.36%comparing with the treatment without root barrier.Each treatment was characterized by monocultured peanut(hd)>intercropped peanut without root barrier(w)>intercropped peanut with plastic sheet root barrier(s)>intercropped peanut with nylon mesh root barrier(n).With the reduction of shading,the net photosynthesis rate was increased,displayed as side 1<side 2<side 3.The net photosynthesis rate,stomatal conductance,transpiration rate of cotton function leaves was increased,and the intercellular CO2 concentration of cotton function leaf was reduced.The net photosynthesis rate of cotton was increased by 24.42%~51.93%.Plastic sheet barrier eliminated underground interaction,the net photosynthesis rate of cotton function leaf was slightly reduced,but was still higher than that of control,which was reduced by 14.67%~17.55%compared with the treatment without root barrier.Each treatment was characterized by intercropped cotton without root barrier(w)>intercropped cotton with nylon mesh root barrier(n)>intercropped cotton with plastic sheet root barrier(s)>monocultured cotton(md).There was an obvious marginal superiority about different root treatments,displayed as side 2>side 1.Meanwhile,the interaction between the root systems was beneficial to improve the photosynthesis of the crop.