Mineralization of Chlormequat chloride (CCC) by different microbial pesticides using different media in grapes

Abstract

Modern agriculture along with different chemical pesticides uses diverse array plant growth regulators which accumulate in fruits and demonstrated residue effect. The Chlormequat Chloride (CCC) belongs to quaternary ammonium growth regulator. This study deals with degradation effect of different fungal and bacterial biopesticides viz. Trichoderma viride, Trichoderma harzianum, Beauveria bassiana, Verticillium lecanii, Penicillium notatum, Bacillus megaterium, Pseudomonas fluorescens, Pseudomonas putida & Bacillus subtilis on solid and liquid media enriched with different concentrations of Chlormequat Chloride. Two fungal biopesticides Trichoderma harzianum and Trichoderma viride significantly indicated growth of 12.20 mm/day 11.48 mm/day average linear growth rates after 3 days of inoculation. These were found to be fast growing biofungicide on Potato dextrose agar and Potato dextrose broth enriched with 2500 mg/l CCC was best growth medium, which was confirmed by increased fresh spore biomass 2.3g/100 & 2.8g/100 ml medium and dry spore biomass 1.25 g & 1.65 g respectively as compared with different growth media. Additionally Bacillus subtilis with 6.366 mm/day & Pseudomonas fluorescens with 1.266 mm/day average colony diameter growth on nutrient agar enriched with 2500 ppm CCC were found to be the fast growing biocontrol agents and it was confirmed by optical density 3.120 and 2.365 respectively, at 560 nm. Remarkable growth of Trichoderma sp., Pseudomonas sp. and Bacillus with CCC indicates that apart from chemical or natural processes microbial degradation proved to be best alternative for seriously pertaining food safety issue.