ASSOCIATION OF Colletotrichum gloeosporioides WITH PREMATURE FRUIT DROPPING OF MANGO (Mangifera indica L.) AND ITS IN VITRO CONTROL USING SELECTED PLANT EXTRACTS, PHYTOHOMONES AND FUNGICIDES

Abstract

The present study was performed to determine the pathogenic cause of mango fruit drop and its in-vitro control through the application of plant extracts, phytohormones, and chemical fungicides. The prematurely fallen fruits at the pin-head stage, pea stage and marble stage were taken for pathogen isolation. Colletotrichum gloeosporioides was identified as the pathogenic cause and several isolates were established. Based on consistent mycelial growth in PDA culture media, one isolate was chosen for in-vitro management study using various treatments. Six plant extracts, two phytohormones viz. NAA, 2,4-D, and six chemical fungicides were tested against C. gloeosporioides. With three treatments, namely garlic clove, allamonda leaf and mahogany leaf extracts, mycelial growth of C. gloeosporioides was not observed for seven days of study. In comparison to the control treatment, a significantly lower mycelial growth was found with both neem leaf extract and marigold leaf extract. Garlic clove extract, allamonda leaf extract and mahogany leaf extract showed the highest percent growth inhibition (100%) of C. gloeosporioides at 7 DAI in compared to the control treatment. In case of NAA and 2,4-D application in PDA, mycelial growth of C. gloeosporioides was not detected also. As a result, extracts of garlic clove, neem leaf, allamonda leaf, mahagoni leaf, NAA and 2,4-D as well as chemical fungicides can be introduced in field conditions to assess their effectiveness in controlling premature fruit drop of mango caused by C. gloeosporioides.