Variability in Colletotrichum spp Causing Anthracnose of Chilli and Management Through Organics

Abstract

The present investigation included roving survey in four major districts newline(Belagavi, Dharwad, Gadag, Haveri) of northern Karnataka, cultural, morphological, newlinemolecular variability of Colletotrichum spp.isolates. Among the surveyed districts from newlinekharif 2020 and 2021, Dharwad district recorded maximum per cent disease index (PDI) newlineof 37.36 followed by Haveri district (36.34 %) whereas, Belagavi district recorded newlinelowest PDI of 32.93.In taluk wise analysis, irrespective of both kharif seasons, Kundgol newlinetaluk of Dharwad district recorded maximum PDI of 50.69 followed by Navalgund newlinetaluk of Dharwad district (47.50 PDI). newlineAnthracnose symptoms initiated with die back symptoms on stem whereas, on newlinegreen fruits it showed water-soaked sunken spots which later covered with salmon newlinecoloured conidial mass and on red ripe fruits, black acervuli developed on sunken spots newlineeither in concentric rings or scattered manner. Pathogenicity on detached fruits newlineconfirmed that, Colletotrichum scovillei can infect both red and green fruits of Byadgi newlinedabbi. C. capsici at the site of inoculation produced black acervuli on red ripe fruits. newlineCultural and morphological characters showed that C. capsici colony colour varied from newlinewhite to grey, produced acervuli with setae and falcate shaped conidia. C. scovillei newlinecolony was dull white to light orange produced acervuli without setae and cylindrical to newlineclavate shaped conidia. The length and breadth of conidia varied from 20.22 to 23.70 newlineµm × 3.15 to 4.10 µm in C. capsici isolates and in the range of 10.07 to 15.35 µm× 3.81 newlineto 4.90 µm among C. scovillei isolates, respectively. newlineMolecular characterization using ITS rDNA amplification (ITS1 and ITS4) newlineshowed amplicon around 550 bp. Among the twenty isolates, the twelve isolates newlineconfirmed as C. capsici formed single cluster and the eight isolates identified as newlineC. scovillei formed another cluster. Molecular