Harnessing resistance sources to develop ToLCV-tolerant hybrids of tomato (Solanum lycopersicum L.)

Abstract

Tomato leaf curl virus disease (ToLCD) is a major constraint in tomato cultivation, and host plant resistance is the best strategy to manage ToLCD. Seven lines reported as field resistant or known to carry Ty genes were crossed with three commercial varieties of Kerala, and the evaluation of seventeen hybrids obtained revealed that the hybrids Vellayani Vijai×EC519806, Akshaya×AVTO1726, Akshaya×EC519806 and Akshaya×AVTO1707 showed high field resistance, while hybrids of EC519806 and Akshaya×AVTO1726 recorded high yield. High glandular to non-glandular trichome density ratio on the abaxial leaf surface was found to be an important factor in determining the tolerance of genotypes under field screening. Markers linked to Ty genes were detected in crosses with AVTO lines, while none of the Ty gene-linked markers were detected in the accession EC519806, which displayed field resistance. Ty 6 was detected in Local Collection (Idukki) and its hybrids. Thus, per se performance, heterosis and disease response of the hybrids in the present study can be utilised for the selection of superior tomato genotypes for future ToLCV resistance breeding programmes.