EFFECTS OF SOWING DATES AND PLANTING DENSITY TO GROWTH AND YIELD OF CUC BONG SOYBEAN IN VO NHAI DISTRICT, THAI NGUYEN PROVINCE

Abstract

The experiment was conducted in the Spring of 2019 in Thai Nguyen, including two independent experiments: the effects of sowing dates and the effect of planting densityto the growth and yield of Cuc bong soybean in Vo Nhai district, Thai Nguyen province. The research results showed that, in the sowing dates experiment, the sowing date 01/3 had a positive effect to tree height, number of first grade branches, leaf area index and yield compared to the other formulas. In this sowing date, theoretical yield reached 33.45 quintals/ha and actual yield was 25.98 quintals/ha, higher than the other sowing dates. In the planting density experiment, at the planting density of 20 plants/m², the number of first grade branches, the total number of pods, weight of thousand seeds were higher than the thick planting density (40 plants/m²), but the theoretical yield and the actual yield were low. At the density of 30 plants/m², the theoretical yield was 36.65 quintal/ha and actual yield was 20.27 quintal/ha, much higher than that of the other planting density.