Screening tomato genotypes for resistance to early blight and American serpentine leafminer

Abstract

In this study, 21 tomato accessions of the ICAR-Indian Institute of Vegetable Research, Varanasi, gene bank were screened for resistance to early blight and leafminer. For early blight resistance, artificial screening was conducted for 40-day-old (in 2013–2014) and 70-day-old (in 2012–2013) plants, and field screening was carried out during 2012–2013. Screening for leafminer damage was done only under screen house conditions during 2012–2013. Tomato wild accessions, namely, EC520078, WIR3928, and WIR3957, showed a lower percent disease incidence of early blight at two different growth stages in artificial disease inoculation conditions and in field conditions. The percent disease incidence of the genotypes was 5.98, 7.22, and 16.48% at 40 days old; 14.59, 12.33, and 16.73% at 70 days old under artificial screening, and 8, 8.65, and 15.12% under field conditions, respectively. The same genotypes recorded lower leafminer damage in screen house conditions, and the percentage of leafminer damage was 3.92, 4.55, and 5.91%. These tomato wild accessions are being used as a source of resistance in early blight and leafminer resistance-breeding programs.