Hybrid analysis for Tolcv (Tomato Leaf Curl Virus) and Root Knot Nematode resistance in tomato (Solanum lycopersicum L.) And molecular validation of Ty-3 and Mi-1 gene

Abstract

Tomato (Solanum lycopersicum L.) is a vital vegetable crop cultivated due to their abundant supply of nutrients, and their recent popularity is mainly accredited to the antioxidant and anti-cancer properties of lycopene. Low productivity in India is due to incidence of both tomato leaf curl virus (ToLCV) and root knot nematode (RKN), resulting in 25–100% yield loss. The aim of this study was to develop and screen tomato hybrids for ToLCV and RKN resistance and validate the presence of the Ty-3 and Mi-1 gene. The study involved evaluating 12 parents, 8 hybrids, and 7 double-cross hybrids carrying genes, which underwent screening at both phenotypic and genotypic levels. An assorted array of Sequence Characterized Amplified Region (SCAR) markers, including P6-25, FLUW-25F, SCAR-1, Mi-23, PMi, and PM3, was utilized to assess the resistance genes linked with ToLCV and RKN, focusing specifically Ty-3 and Mi-1. These markers demonstrated high reliability in distinguishing susceptible and resistant lines, facilitating the efficient identification of homozygous or heterozygous alleles. The screening for ToLCV and RKN resulted in the identification of three resistant parents (CBESL159, CBESL162, CBESL169), two hybrids (H5-CBESL133×CBESL169, H7-CBESL146×CBESL162), and two double hybrids (H5xH7 and H4xH5). These promising parents hold potential as parental materials for developing lines or hybrids with genes providing strong and enduring resistance against ToLCV, RKN and yield improvement. The double hybrids can be used for the development of breeding lines.