施钾对夏花生产量、品质及光温生理特性的影响OA北大核心CSTPCD

[Objective]The effects of different potassium levels on the yield and quality of summer peanuts at the maturity stage,the dynamics of potassium accumulation at the growth stage,physiological characteristics of light and temperature,and root morphology were explored to provide a scientific basis for rational application of potassium in peanut.[Method]A field experiment was conducted in Wen County,Henan Province,from 2021 to 2022.The peanut cultivar of Yuhua 22 was used as test material,and 5 potassium fertilizer treatments was set,including 0(K0),45(K45),90(K90),135(K135)and 180(K180)kg·hm-2.The yield and quality indexes of summer peanut pods were determined at the maturity stage.Leaf SPAD value,canopy photosynthetically active radiation and canopy temperature were measured at the seedling stage,flowering-pegging stage,pod-setting stage and pod-filling stage,respectively.The potassium accumulation in plants and root morphology were analyzed too.[Result]With the increase of potassium application rate,the pod yield of peanut in 2 years could be fitted by"linear + platforms trends"and"quadratic equation with one variable",respectively,and the appropriate potassium application rate was 164 and 135 kg·hm-2,respectively.Potassium application increased yield by 17%on average.The content of crude protein,oil and amino acid in grain at maturity showed a trend of"first increasing and then stabilizing"with the increase of potassium application.Compared with no potassium application,the average increase of crude protein,oil and amino acid contents in grain under potassium application was 7.85%,3.98%and 13.97%,respectively.The Logistic equation was applied to the nonlinear regression fitting of potassium accumulation in summer peanuts.The results showed that potassium application mainly increased the maximum accumulation rate(Vmax)and average accumulation rate(Vmean),delayed the occurrence of peak absorption(Tmax),and prolonged the rapid accumulation period(Δt)and active accumulation period(Taas)to promote the sustainable and rapid growth of summer peanuts.In addition,the maximum,minimum and mean canopy temperatures decreased significantly with increasing potassium application at all fertility stages.Compared with K0,135 kg hm-2 treatment significantly increased the leaf SPAD value and canopy photosynthetically active radiation(APAR)and component(FPAR)of peanut and had a positive effect on root morphology.The utilization efficiency of potassium fertilizer decreased gradually with the increase of potassium application.[Conclusion]Reasonable application of potassium could significantly improve the yield and quality of summer peanut,promote the accumulation and utilization of potassium,and significantly improve the physiological properties of light and temperature during the growth period.The recommended potassium application amount of summer peanuts under this test condition was 135-160 kg·hm-2.