Abstract:

To clarify the change trend and law of main agronomic characters of soybean varieties approved in different years in Inner Mongolia Autonomous Region, and promote soybean breeding, the main agronomic characters, quality and yield of soybean varieties approved by Inner Mongolia Autonomous Region from 2002 to 2020 were comprehensively analyzed. The number of main stem nodes showed an upward trend as a whole, the number of growth days showed no significant change as a whole, and the plant height, the number of effective branches per plant and 100-kernel weight showed a downward trend as a whole. The content of crude protein increased slightly, while the content of crude fat decreased. Among the approved soybean varieties, there were 8 high protein soybean varieties, accounting for 7.08% of the total approved number, and 42 high oil soybean varieties, accounting for 37.17% of the total approved number. The yield of soybean varieties approved from 2002 to 2020 showed a gradual upward trend, and the yield of ‘Xingdou 7’ reached the highest of 3531.0 kg/hm² in 2019. Correlation analysis showed that there were complex correlations among the characters, and the yield was positively correlated with the number of growth days; the yield had a significantly positive correlation with the plant height and crude fat content, and the correlation coefficients were 0.298 and 0.274, respectively. The yield had a very significantly positive correlation with 100-kernel weight and the number of main stem nodes, and the correlation coefficients were 0.494 and 0.414, respectively. The yield was negatively correlated with the effective branch number per plant, and significantly negatively correlated with the crude protein content, and the correlation coefficients were 0.189 and 0.414, respectively. The increase of 100-kernel weight is the key factor to increase the yield of soybean in Inner Mongolia Autonomous Region. Therefore, in the process of soybean breeding, attention should be paid to the combination of parents with high 100-kernel weight and moderate number of main stem nodes and the selection of individual plant of future generation. At the same time, attention should also be paid to quality and resistance, so as to select new soybean varieties with high yield, high quality, multi-resistance and wide adaptability in Inner Mongolia Autonomous Region.

Key words: soybean, approved varieties, agronomic characters, quality, yield