Abstract:

The purpose of this paper is to clarify the correlations between different varieties, planting densities, nitrogen application rates and sowing modes and the biological characters and yield of waxy sorghum. The L₉ (3⁴) orthogonal experiment method was adopted in the study. The results showed that the effects of waxy sorghum varieties on biological characters were quite different. As the planting density increased, the plant height increased, while the number of grains per ear and the single ear weight decreased. The planting density had no obvious influence on the number of leaves, stem diameter, ear length and 1000-grain weight. Waxy sorghum with nitrogen application rate of 255 kg/hm² had the best ear length, number of grains per ear, single ear weight and 1000-grain weight. Different planting modes had little effect on biological characters. The plant height, leaf number, number of grains per ear and single ear weight were positively correlated with the yield, while stem diameter, ear length and 1000-grain weight were negatively correlated with the yield. Variety is the main factor affecting the yield, followed by planting density and planting mode. The yield of the combination A₂B₃C₁D₂ was the highest, reaching 12257.28 kg/hm², followed by that of the combination A₂B₁C₂D₃, reaching 11553.91 kg/hm². The yield difference of different varieties reached a very significant level, the yield difference of different planting densities reached a significant level, and the yield difference of different nitrogen application rates and planting modes were not significant, so the optimal combination was A₂B₃C₁D₂ or A₂B₁C₂D₃. This study provides a scientific basis for high-yield and high-quality planting technology of waxy sorghum.

Key words: waxy sorghum, planting density, nitrogen application rate, sowing mode, biological character, yield