Effect of Nitrogen Fertilization and Cover Crops On Juice, Sugar, and Bagasse of Sweet Sorghum.

Higher yield is required from a sustainable bioenergy cropping systems but efficient use of inputs is equally important. Efforts are needed to optimize production of sweet sorghum for bioenergy use. Sweet sorghum (Sorghum bicolor L. Moench) var EJ7281 was planted and the plots were provided with input combinations of two nitrogen fertilization rates (0 kg ha^-1 and 90 kg ha^-1) and three winter cover crop treatments, viz., annual rye, hairy vetch, and annual rye plus hairy vetch. Juice content of sweet sorghum stalk ranged from 9.58 – 19.45% by weight. The juice yield ranged from 4.63-9.75 m³ ha^-1 while the juice sugar yield ranged between 0.85-1.76 Mg ha^-1. Only rye along with vetch and no fertilizer showed significantly higher juice yield and juice sugar yield than control. The dry bagasse yield ranged between 12.35 and 18.21 Mg ha^-1 with no significant differences in comparison to control. The results suggest that use of rye along with vetch and no fertilizer could be an alternative to minimize inputs for sweet sorghum production and mitigate fertilizer induced greenhouse gas emissions.