Abstract:

The aims are to investigate the relationship between major agronomic traits and biological yield of sweet sorghum, select sweet sorghum materials with excellent overall performance, and provide a theoretical basis for sweet sorghum breeding in the future. The main agronomic traits and biological yield of 24 sweet sorghum cross combinations were subjected to grey correlation degree analysis, correlation analysis, path analysis and principal component analysis. The results showed that the variation coefficient of main spike length and grain number per spike was large; and the grey correlation degree results showed that the correlation degree between sugar brix and biological yield was the largest. Correlation analysis showed that plant height and stalk length, main spike length and 1000-grain weight had highly significantly positive correlations. The path analysis results showed that the direct effects of main panicle length, stem length, 1000-grain weight, juice extraction rate and sugar brix on the biological yield of sweet sorghum were positive. Principal component analysis showed that the seven traits of plant height, stalk length, grain number per spike, sugar brix, juice extraction rate, main spike length, and biological yield were more influential to the overall performance of the varieties. Therefore, in the selection of sweet sorghum hybrids, we should focus on sugar brix, stem thickness and stalk length, while take into account the height of the plant, number of grains per spike, length of the main spike, juice extraction rate, and 1000-grain weight.

Key words: sweet sorghum, agronomic traits, grey correlation degree analysis, path analysis, principal component analysis