Effects of Single-seed Sowing on Root Growth, Root-shoot Ratio, and Yield inPeanut ( Arachis hypogaca L.)

Abstract

Peanut cultivar Huayu 22 was used to study the differences between single-seed sowing and double-seed sowing modes on root growth, root and shoot relationship, and yield under corresponding planting density. The two single-seed sowing treatments were 195 000 holes per hectare(S1) and 225 000 holes per hectare(S2), respectively with the double-seed sowing(150 000holes per hectare) as control. During the growth period, dry weights, length, volume and absorption area of the root under three treatments increased and reached the maximum at 40–50 days after flowering, and then decreased. The average root diameter decreased and reached the minimum at 50–60 days after flowering, and then increased. The dry weight of aboveground part and pod increased while the root-shoot ratio decreased continuously. S1 and S2 treatments could improve dry weight of the seedlings,the length, the volume, the absorption area of the roots and the root-shoot ratio, and reduce average root diameter during the whole growth period, especially at the late growth period. Additionally, S1 treatment saved 35% sowing seeds and improved peanut yield by 7.98%–8.38%. These results indicated that single-seed sowing could improve peanut yield through guaranteeing relatively stronger root growth predominance, regulating root-shoot ratio, and increasing the productivity potential for each seedling.