Screening of Bitter Gourd (Momordica charantia L.) Germplasm against Downy Mildew under Field Conditions

AbstractThe present study was undertaken to screen various bitter gourd genotypes for resistance against downy mildew caused by Pseudoperonospora cubensis under natural field screening conditions. The experiment was laid out in a RCBD with two replications during the 2022–23 season evaluating 75 genetically diverse bitter gourd genotypes including commercial varieties and improved lines. None of the genotypes showed complete resistance to the pathogen. The percentage disease index (PDI) observed under natural conditions ranged between 23.98 to 86.77 per cent. The results indicated that the minimum percent disease index (PDI) of 23.98 per cent was recorded in genotype Green Long followed by 29.46 (IC470565), 34.22 (IC68335), 36.09 (PVIG-2) and 37.33 (IC467681) suggesting moderately resistant to downy mildew. The maximum PDI was recorded in the genotype Kashi Mayuri with 86.77 per cent followed by 86.14 (MC-3), 86.10 (Hirkani), 82.33 (UHSB-025) and 82.28 (IC113875) genotypes were found to be susceptible to downy mildew under field conditions. Thus, the identified bitter gourd genotypes can be used for further breeding programme for the development of new bitter gourd hybrids (or) varieties with downy mildew resistance.