Effects of Lime and Leaf Surface Inhibitor on Photosynthetic Characteristics and Yield of Peanut in Light Cadmium-Contaminated Soil
To explore the green cultivation technology of peanut in mildly cadmium polluted land,lime and leaf surface inhibitor were used as control measures to study their effects on photosynthetic characteris-tics,yield and cadmium content of peanut seeds.The field test was carried out with peanut variety Xiang-hua2008 as the material,and a control and 5 treatments were set as following:2,250 kg/ha lime base(L),spray foliar surface control agent 1(L1),spray foliar surface control agent 2(L2),combined application of lime+foliar surface control agent 1(L+L1),combined application of lime+foliar surface control agent 2(L+L2).The photosynthetic parameters,fluorescence parameters and chlorophyll content of peanut were de-termined in the main growth stages,and the yield and cadmium content of peanut kernel were determined in the pod-filling stage.The results showed as following:① Photosynthetic parameters:basal application of lime,leaf surface inhibitor 1 and their combined application could enhance the photosynthetic performance of peanut(Pn,Tr and Gs increased)at flowering-pegging and pod-bearing stage,but decreased at pod-filling stage;The photosynthetic parameters(Pn,Tr,Gs)of leaf surface inhibitor 2 and its combination treatment were lower than those of control at flowering-pegging stage,but increased slightly at pod-bearing stage.Ci of each treatment was lower than that of control at pod-bearing stage and pod-filling stage.② Fluorescence parame-ters:the Fo and Fm levels of base lime and leaf surface inhibitor 1 were higher than those of the control,and Fv,Fv/Fo and Fv/Fm levels were higher than those of the control at pod-bearing stage and pod-filling stage.The pa-rameters of foliar control agent 1 were higher in seedling stage and pod-filling stage than that of control.The Fm,Fv,Fv/Fo and Fv/Fm of foliar control agent 2 and its combination treatment were lower than the control at seedling stage,flowering-pegging stage and pod-filling stage.③ The SPAD value of all treatments was higher than that of the control group except the pod-bearing stage,but the difference was not significant.④ Pod yield:base application of lime,foliar control agent 1 and its combination treatment increased peanut yield,while foliar control agent 2 and its combination treatment reduced peanut yield compared with the control.⑤ Correlation a-nalysis showed that Pn,Gs,Ci at flowering-pegging stage,Fv/Fo and Fv/Fm at pod-filling stage were signifi-cantly positively correlated with yield.⑥ Cadmium content of seed kernel showed that all treatments could re-duce cadmium content of peanut seed kernel,and reached the national green food standard.In conclusion,lime base application,foliar control agent 1 spraying and their combined application can optimize plant photosynthetic performance,reduce cadmium content in seeds and increase peanut yield,and can be used as green control meas-ures for peanut in mildly cadmium polluted land,especially lime base application exhibited the best result.
万方数据
维普
