Response of biomass, grain production, and sugar content of four sorghum plant varieties (Sorghum bicolor (L.) Moench) to different plant densities

Abstract

Sorghum (Sorghum bicolor (L.) Moench) is a potential plant for food, livestock feed, biofuel, sugar, alcohol, and other bioindustry products. Sorghum could be adaptable to grow and expand in marginal areas of the world. Varieties of sorghum have their specific morpho-agronomic characters. It would be significant to compare the performance of multiple sorghum varieties to identify a suitable one for the intended use. The increase in biomass plant production could be caused by cultivation factors, such as an increased planting density. This study aims to determine the response of four different sorghum varieties to the treatment of the plant density on the biomass, grain production, and sugar content of stem juice. This research was conducted using two factors: sorghum variety ("Super 1,""Keler,""Lepeng,"and "Rio") and the plant density (two, four, and six plants per hole or 106,667; 213,333; and 320,000 plants ha-1, respectively). The results of the study showed that all four sorghum varieties tested could be used as biomass resources. The highest plant dry biomass was gained from six plants per hole with 44.0 t ha-1, whereas the lowest one was two plants per hole with 30.4 t ha-1. "Super 1"was a superior variety due to the significant highest sugar content of the stem juice (13.9°Brix) and grain production. "Lepeng"variety was the lowest in both sugar content (8°Brix) and grain production, whereas "Keler"and "Rio"varieties contained sugar in between 8.5 and 10.8°Brix of the stem juice.