不同地膜残留量对棉花光合特性及生长发育的影响OA

In order to investigate the effects of different residual plastic film on cotton growth,develop-ment,photosynthetic physiological characteristics and yield formation,a small-plot simulation experiment was conducted in the gray desert soil region of Xinjiang,using Xinluzao 53 as the test variety,with 6 plas-tic film residue gradients[0(control),250,500,1 000,1 500,2 000 kg/hm2].The results showed that,compared with the control,the net photosynthetic rate of cotton leaves was significantly reduced when the residual plastic film exceeded 500 kg/hm2(P<0.05),and the SPAD value was significantly reduced in the 1 500 kg/hm2 treatment(P<0.05).Light response characteristics indicated that,compared with the con-trol,the maximum net photosynthetic rate decreased by 28.98%in the 500 kg/hm2 treatment(P<0.05),and the net photosynthetic rate and light saturation point were significantly reduced(P<0.05).The light compensation point and dark respiration rate in the 250 kg/hm2 treatment were significantly higher than those in the control(P<0.05).The control group had the highest seed cotton yield(5 169.62 kg/hm2),while cotton yield was significantly reduced in all residual film treatments(P<0.05).Correlation analysis showed that plant height was significantly positively correlated with SPAD value(P<0.05),stomatal conductance was extremely significantly positively correlated with intercellular CO2 concentration(P<0.01),and yield was positively correlated with plant height,SPAD value,and maximum net photosynthetic rate.Residual plastic mulch affects plant growth by inhibiting the photosynthetic capacity of leaves,there-by leading to a decrease in yield.