Sources of Resistance to Anthracnose (Colletotrichum truncatum) in Chili (Capsicum annuum L.)

Anthracnose, caused by Colletotrichum spp., is a major constraint to chili ( Capsicum annuum ) cultivation, particularly in tropical regions. Colletotrichum species cause water-soaked, sunken lesions on both red and green fruits, rendering them unmarketable. Host plant resistance offers an effective, environmentally friendly, and economically viable management strategy. We sought to identify resistance sources against Colletotrichum truncatum in C. annuum . One hundred forty-one chili entries were evaluated in the field during Sep 2023 using an augmented block design. Fruits from each entry were inoculated with C. truncatum using the fruit puncture method. Analysis of variance revealed significant differences among entries for the average lesion diameter. Four entries (DCA 59, DCA 68, DCA 134, and DCA 336) were identified as highly resistant, and 20 entries had moderate levels of resistance. As expected, most of the entries were susceptible to anthracnose, with 62 entries (44%) being susceptible and 55 entries (39%) classified as highly susceptible. The genotypic coefficient of variation (GCV, 40%) and phenotypic coefficient of variation (PCV, 42%) were both high, indicating substantial genetic variability and strong potential for selection. The narrow difference between PCV and GCV suggests minimal environmental influence on the expression of the trait. This study provides a basis for future research and the development of breeding anthracnose-resistant chili varieties.