Microbial treatments enhance nutritional quality and in-vitro dry matter digestibility of maize (Zea mays L.) stover

Abstract

Low nutritional value, poor voluntary intake and digestibility limit the utilization of maize stover in livestock feeding. Different microbial treatments (Trichoderma harzianum, Trichoderma viride, Saccharomyces cerevisae and Pseudomonas fluorescens) were evaluated for improving the quality and digestibility of 24 genotypes of maize stover. Treatment of maize stover with P. fluorescens and S. cerevisiae resulted in increase of CP content (11.82% and 10.56%) compared to control (8.54%). Out of four microbial strains T. viride has a positive effect on enhancing the total carbohydrate content, where maize stover (Vivek) exhibited significantly highest increase in total carbohydrate content (21.81%). Treatment of maize stover with T. harzianum reduced the NDF content to 65% in African Tall while treatment with P. fluorescens reduced it to 65.8% in Palam Shankar Makka in comparison to control (69 and 67.2%, respectively). Reduction in lignin content of maize stover (3.00% in PMG-52-1) was observed after treatment with T. viride in comparison to control (7.20%). Treatment of maize stover with T. viride and P. fluorescens was most effective in reducing the total phenolic content of PMG-97 and PMG-95 and African Tall genotypes of maize stovers, respectively. Treatment with T. harzianum and P. fluorescens reduced total tannins contents most effectively in Palam Shankar Makka and PMG-93-1, respectively. P. fluorescens followed by S. cerevisiae treatment resulted in a decrease in silica content of maize stover to the extent of 0.87% and 0.6% in maize stover of PMG-95 genotype, compared to control (1.8%). Digestibility of maize stover improved with all biological treatments, the highest significant increase (69.2%) was observed with T. harzianum treatment compared to control (52.1%). The results of the study revealed that T. viride is the most promising fungi for improving the quality and digestibility of maize stover of different genotypes, followed by T. harzianum. The bacteria P. fluorescens was found to be equally efficient in improving the quality and digestibility of maize stover. The genotype x treatment interaction was found to be significant for all the traits indicating that the microbes could efficiently enhance different quality traits in maize stover.