Effects of single-seed sowing on dry matter accumulation and root,canopy structure of peanut
In order to clarify the mechanism of yield increase of single seed precision sowing,two sowing types of single-seed sowing(SS)and double-seed sowing(DS,as control)were set with Huayu 22 under field conditions,dry matter accumulation,leaf area index,canopy structure,and root characteristics of peanut at different growth stage were compared.The results showed that there was no significant difference in dry matter weight of single plant and population between SS and DS in the early growth stage of peanut,but SS was significantly higher than DS in the middle and late growth stage,and the leaf area index of SS was significantly higher than that of DS in the pod setting stage.As to different canopy structures at pod setting stage,the leaf area index of upper,middle and lower canopy layers of SS were 23.03%,9.34%and 86.43%higher than those of DS,respectively.The dry weight of leaf and stem per single plant and population canopy of SS was significantly higher than that of DS,in addition the proportion of dry weights of leaves and stems in the lower part of SS was higher.The total root dry weight,root length,root surface area and root volume per plant and popula-tion of SS were higher than those of DS,and the proportion of middle and lower layer roots were higher.The results of cor-relation analysis showed that there was a significant positive correlation between root dry weight and leaf dry weight in the middle,lower layer,and stem dry weight in the lower layer.In conclusion,compared with double-seed sowing,the stronger development of the middle and lower parts of the canopy and the deeper root distribution of single seed precision sowing are the important reasons for its yield increase of peanut.It is an effective way to reduce cost and increase yield for peanut for promote root development and stronger canopy by single seed precision sowing.