Nutritional evaluation of the plant and silage of different sorghum hybrids (Sorghum bicolor, L. Moench)

The experiment was conducted with the purpose to evaluate the nutritional value of the plant and silage of different sorghum hybrids: AGX-213, AG-2002, AGX-217 e AG-2005E. The AG-2005E hybrid was the most precocious with 125 days between sowing and harvesting, while the AGX-213 was the latest with 151 days. The plants of the forage hybrids AG-2002 and AGX-213 were taller and showed higher dry matter production than the double purpose hybrids AGX-217 and AG-2005E. The AG-2005E hybrid plant showed higher particle percentage (58.4%) and lower percentages of stem (20.1%) and leaves (21.5%), while the forage hybrids AGX-213 and AG-2002 showed higher stem percentage, 45.1 and 56.8%, respectively. The plant dry matter contents did not change with silage fermentation. No differences were observed among the silages of the sorghum hybrids for the content of neutral detergent fiber, lignin and total ash in ADF. The AG-2005E silage presented lower values of acid detergent fiber (28.96%) and cellulose (24.19%) and higher content of dry matter (35.50%) in comparison with the other hybrids. No differences were observed among the silages of sorghum hybrids for organic matter, in vitro organic matter digestibility and digestible energy concentration. The percentage of TDN was higher for the double purpose hybrids AG-2005E (62.20%) and AGX-217 (60.05%) than for the forage hybrids AGX-213 (56.77%) and AG-2002 (56.40%).