The effect of method, timing and norms of bentonite application on plant density of soybean seeds

Abstract

The effect of method, timing and rate (100–750 kg $\text{ha}^{-1}$) of bentonite application with $N_{90}P_{60}K_{90}$ on field emergence, plant density and nodulation of soybean cv. ‘Uzbek-6’ was studied on light serozem soils of Kashkadarya region. Bentonite applied at sowing increased field emergence from 84.1 % to 84.8–87.2 %, final plant density by 1.5–6.8 % and nodule number at budding by 10.1–26.6 %. Plant density was closely correlated with bentonite rate (r = 0.925–0.991), field emergence (r = 0.924) and nodule number (r = 0.855). The optimal rate was 400 kg $\text{ha}^{-1}$ at sowing.