Selecting high-yield forage sorghum genotypes for ensiling: agronomic traits, fermentation parameters, and nutritional value

This study aimed to evaluate agronomic traits of 18 forage sorghum genotypes (Sorghum bicolor L.) (14 experimental and four commercial ones), and select those most promisor for forage accumulation (Experiment 1). Concomitantly, the study aimed to assess fermentation, chemical composition, and rumen kinetics characteristics of seven of the 18 genotypes, being five experimental with high dry matter yield (DMY) and two commercial ones (Experiment 2). In Experiment 1, the highest DMY was observed in the experimental genotype 6 (25.1 t/ha), while the lowest was found in the commercial one 15 (9.8 t/ha). Tocher grouping analysis revealed six groups of genotypes and great genetic diversity among materials. In Experiment 2, silages displayed a pH value of 3.66, on average, with an aerobic stability of 127.4 h. Silages of experimental genotypes 3, 4, 10, and 14 yielded higher degradable dry matter per area (9.8 t/ha, on average). Genetic diversity identified in this study allows for selecting forage sorghum genotypes with high DMY and appropriate fermentation and nutritional parameters for ensiling. Experimental genotypes 3, 4, 10, and 14 enable producing silages with similar fermentation profiles to the commercial genotypes 16 and 18 but with more digestible nutrients per area.