INVESTIGATING THE EFFICACY OF BIOCONTROL AGENTS AGAINST ROOT ROT DISEASES IN TOMATO CROPS

Abstract

This study investigates the efficacy of biocontrol agents (BCAs) against root rot diseases in tomato crops, focusing on Trichoderma harzianum, Bacillus subtilis, and Pseudomonas fluorescens. Laboratory and field trials were conducted to assess pathogen suppression, plant health, and yield improvements. Results from laboratory trials revealed that Trichoderma harzianum exhibited the highest reduction in pathogen populations, with a 65% decrease in Fusarium oxysporum, compared to 50% and 45% for Bacillus subtilis and Pseudomonas fluorescens, respectively. Root health was significantly improved in BCA-treated plants, with Trichoderma harzianum achieving the lowest root rot severity score (1.2). Field trials confirmed these findings, showing that plants treated with BCAs exhibited superior growth, with Trichoderma harzianum plants reaching an average height of 35 cm and yielding 320 g of fruit per plant, compared to 18 cm and 180 g in the control group. Microbial populations in the rhizosphere also increased, particularly with Trichoderma harzianum, indicating a positive impact on soil health. The study concludes that BCAs are a promising sustainable alternative to chemical pesticides for managing root rot diseases in tomato crops. The findings highlight the potential of Trichoderma harzianum as the most effective biocontrol agent, offering significant improvements in pathogen suppression, plant growth, and yield, while promoting beneficial microbial communities in the soil. Further research is needed to optimize BCA application techniques and understand their performance under varying environmental conditions.