Evaluating the promise of Trichoderma and Anabaena based biofilms as multifunctional agents in Macrophomina phaseolina-infected cotton crop

The influence of biofilmed formulations composed of Trichoderma viride and Anabaena torulosa as matrices was investigated in Macrophomina phaseolina (Tassi) Goid.-infected cotton crop, in terms of plant growth and biocontrol parameters. Trichoderma based biofilms were developed with Azotobacter chroococcum, Pseudomonas fluorescens and Bacillus subtilis, while A. torulosa biofilms were prepared using B. subtilis and T. viride as components. Scanning electron microscopy revealed significant colonisation of biofilms on the root surface, which could be correlated with lowest mortality of 5.67%, recorded using T. viride-B. subtilis biofilm. An increase of 4-7% in polyphenol oxidase enzyme activity was recorded in all biofilm-treated samples, particularly those in which B. subtilis was present. The highest value of 1360.22 mu g microbial biomass carbon g(-1) soil was recorded in Anabaena-B. subtilis biofilm treatment. Significantly higher values of plant and soil nutrient parameters in treatments in which biofilms were used vis-a-vis individual cultures reveal their promise. Such novel biofilmed biofertilizers with multiple useful traits can be beneficial options for effective nutrient and pest management of cotton crop.