Evaluating Herbicides Bio-efficacy on Yield, Quality Parameters of Sweet Sorghum and Their Residual Effects on Soil Microbial Diversity

An experiment was carried out at Instructional Farm, Department of Agronomy, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat). The aim of the research is to evaluate herbicides bio-efficacy on yield, quality parameters of sweet sorghum and their residual effects on soil microbial diversity. The higher grain yield and fodder yield (kg ha-l), reducing, non-reducing sugars and total sugar in juice were recorded under weed-free plot (T9), which was statistically at par with the treatments IC & HW at 15 and 30 das (T8), PE application of atrazine 50 WP 500 g/ha fb mesotrione + atrazine 44.97 SC (premix) 875 g/ha at 30 DAS, (T7) and PE application of atrazine 50 WP 500 g/ha + IC & HW (T1). Before sowing, no significant differences in microbial population were observed. At 20 days after herbicide application, the weedy check plot (T10) had the highest microbial population, similar to weed-free and manual weeding treatments. Herbicide-treated plots had lower microbial populations. At harvest, the highest microbial population was found in atrazine 50 WP 500 g/ha (PE) followed by tembotrione 42 SC 100 g/ha (PoE) which remained statistically at par with the rest of herbicidal treatments.