Effects of reducing chemical fertilizer and applying organic fertilizer on the photosynthetic characteristics,yield,and soil fertility of Capsicum an-nuum L.

LIU Yongpeng; DONG Xiaoyu; QIN Suyan; ZHAO Yueqiang; LIU Tian; LIU Wei; ZHU Xinhong; YANG Fan; YAO Qiuju

doi:10.16861/j.cnki.zggc.2024.0616

Abstract：In order to solve the problem of heavy application of chemical fertilizers and light application of organic fertil-izers in the main production areas of Capsicum annuum L.,the effects of reducing chemical fertilizers and applying organic fertilizers on the growth,photosynthetic characteristics,yield,and soil fertility of Capsicum annuum L.were studied.Using Sanying No.9 as the experimental material,a field experiment was conducted with an increase of 200 kg and 400 kg of organic fertilizer as the basis,and two gradients of reducing fertilizer application by 15％and 30％were set,respectively.The results showed that in terms of growth indicators,the T3 treatment(increasing the application of 400 kg organic fertil-izer and reducing the application of 15％chemical fertilizer)had the most significant increase in plant height,stem thick-ness,expansion,branch number,maximum leaf area,circumference,length,and width of Capsicum annuum L.compared with the control.The SPAD value and nitrogen content in the leaves were also highest under T3 treatment,which increased by 27.23％and 29.04％,respectively,compared to CK(blank fertilization).In terms of fruit and yield indica-tors,T3 treatment had the highest average fresh and dry mass per fruit,the least number of flower skin fruits,and the highest yield,with an increase of 15.18％compared to T1(conventional fertilization).In terms of soil fertility,T3 treatment was the most effective in increasing soil organic matter content and pH,and was most beneficial for improving the accumula-tion of available nutrients in the soil from the growth period to the fruiting period.In summary,increasing the application of 400 kg organic fertilizer and applying 63.75 kg(15％reduction)of chemical fertilizer.are most beneficial for the growth in Capsicum annuum L.and accumulation of organic matter,as well as increasing soil organic matter content and coordinating soil nutrient balance.It is recommended to promote their application in production.