Comparison of dry matter accumulation and N, P, K uptake and distribution in different organs and yield on hybrid cotton and conventional cotton

Dry matter accumulation, N, P, K uptake and distribution, and yield of hybrid cotton (Yu za 35) and conventional cotton (CRI 41) was studied under field condition. Fertilizer application rate was set at N 225 kg/ha, P2O5 90 kg/ha and K2O 135 kg/ha, and a randomized complete block design was used with three replicates. The results indicated that the patterns of accumulation of dry matter and N, P, K at different growth period for hybrid cotton were similar to conventional cotton, but accumulation quantity of dry matter and N, P, K in hybrid cotton was higher than that in conventional cotton. Accumulation rates of dry matter and N, P, K in hybrid cotton at later growth period was higher than that in conventional cotton indicating that hybrid cotton had more obvious heterosis in growth. The results also indicated that the distribution rate of dry matter and N, P, K to reproductive organs was continuously increased with the growth of cotton, and the distribution rates in hybrid cotton was higher than that of conventional cotton. When lint yield of hybrid cotton was 1778.23 kg/ha, the absorption quantity of N, P2O5 and K2O was 242.92, 82.12 and 247.76 kg/ha, respectively, and the uptake proportion of N, P2O5 and K2O was1:0.34:1.02. When lint yield of conventional cotton was 1377.21 kg/ha, the absorption quantity of N, P2O5 and K2O was 195.42, 65.64 and 194.09 kg/ha, respectively, and the uptake proportion of N, P2O5 and K2O was1:0.34:0.99.