Influence of intercropping sweet sorghum with climbing bean on forage yield and quality

Abstract

Sweet sorghum (Sorghum bicolor L.) is an important silage crop and has an increasing popularity because of the need for relatively smaller quantities of water per unit dry matter production compared to maize. Regarding to high feed costs of protein supplementations, legumes can be used in livestock nutrition for their high protein content and, thus, providing cost savings. Since legumes have low dry matter yield, acceptable forage yield and quality can be obtained from intercropping cereals and legumes, compared to their sole crops. In this study, sweet sorghum (Sorghum bicolor L.) and climbing bean (Phaseolus vulgaris L.) intercropped in different sowing densities and pure sweet sorghum crops were evaluated to the best intercropping system with respect to yield and quality of fodder. Sweet sorghum was sown alone (18.0 seeds/m2) and intercropped with climbing bean as follows: 18.0 seeds/m2 of sweet sorghum and 3.7 seeds/m2 of climbing bean, 18.0 seeds/m2 of sweet sorghum and 5.0 seeds/m2 of climbing bean and 18.0 seeds/m2 of sweet sorghum and 7.5 seeds/m2 of climbing bean. The highest dry matter yield was produced by 18.0 plants/m2 of sweet sorghum and 7.5 plants/m2 of climbing bean (20.7 t/ha), and the lowest by solo sweet sorghum (18.2 t/ha). Intercropping of sweet sorghum with climbing bean reduced neutral detergent fiber content, which in turn, results in increased forage digestibility. Based on forage yield and quality, this study showed that among all intercropped forages, of 18.0 plants/m2 of sweet sorghum and 7.5 plants/m2 of climbing bean treatment were better performing than other intercrops.

Keywords

• sweet sorghum
• bean
• yield
• crude protein
• calcium