Abstract:

In order to guide the production of mixed silage of corn and soybean intercropping and select suitable soybean varieties, 17 soybean varieties were tested with corn variety ‘Zheng hong 6’ by observing the changes in yield and moisture content of mixed silage during a certain symbiotic period to determine the appropriate harvest time. Grey correlation analysis was used to explore the correlation between 8 indicators of soybean and hay yield, as well as to comprehensively evaluate the performance of soybean varieties. It was found that when the symbiotic period between corn and soybean was 103 days, the mixed hay yield of all corn-soybean combinations reached its peak and the moisture content decreased to below 70%. The top 3 traits that were highly correlated with soybean hay yield were plant height (0.761), reproductive growth period (0.752), and full growth period (0.734), and the top 3 varieties in comprehensive evaluation were ‘Nan chun dou 50’ (0.820), ‘Qi huang 34’ (0.807), and ‘Hua chun 6’ (0.741). For the purpose of mixed silage production, it is advisable to choose tall and late-maturing soybean varieties, especially those with a longer reproductive growth period. The highest hay yield can be obtained by harvesting the mixed silage at a symbiotic period of 103 days in this region.

Key words: corn-soybean intercropping, suitable harvesting period for silage, agronomic traits of soybean, variety evaluation, grey correlation analysis