Trichoderma sp as a Biological Control Agent in the Postharvest Treatment of Mango Stem-End Rot

Stem-end rot caused by Botryodiploidia theobromae is one of the most economically important diseases of mango. Currently the disease is controlled by fungicides. Due to the residual effect and biosafety issues to the health and environment caused by fungicides, this study was initiated to investigate the potential use of fungal antagonist (Trichoderma sp.) against B. theobromae and its effectiveness as compared to fungicides. The mango cuultivar 'Sala' was used in this study. Treatments applied were propiconazole sprayed at 500 ppm and three different spore concentrations at 1x10(3), 1x10(6) and 1x10(8) conidia/ml of Trichoderma sp. with and without inoculation of B. theobromae. The severity of the disease was determined at 0, 2, 4, 6 and 8 days post inoculation based on disease lesion. When B. theobromae inoculated on mango, spore concentration of Trichoderma 1x10(6) and 1x10(8) conidia/ml showed good potential to control stem-end rot but control levels was not as high as using propiconazole. All the fruits without inoculation with B. theobromae did not develop any disease symptom until day 4 for all treatments. Treating the mangoes by spraying with three different spore concentrations of Trichoderma sp. and 500 ppm propiconazole did not have significant effect as compared to untreated (control) mango. Disease started to develop at day 6 for fruit sprayed with all the three concentrations. All treatments including control showed that the percentage of lesion had a value ranging from 0-2%. This study revealed that fungal antagonist of Trichoderma sp. with spore concentration of 1x10(8) and 1x10(6) conidia/ml has the potential for postharvest disease control and thus needs further evaluation.