Evaluation of Indigenous Tomato Varieties for Resistance to Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Surkhet, Nepal

Abstract

The South American tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera- Gelechiidae), is an invasive pest threatening tomato production in Nepal. This study evaluated sixteen indigenous tomato varieties (Solanum lycopersicum L.) for growth, yield, and resistance to T. absoluta under field conditions in Surkhet, Nepal, during summer 2025, The experiment used a randomized complete block design with three replications. Data on growth parameters, yield attributes, and leaf and fruit damage were subjected to analysis of variance. Significant genetic variability (p<0.001) was observed among varieties for all traits. Plant height ranged from 57.5 to 116.0 cm. and total fruits per plant varied from 12.5 to 239.5. Leaf damage ranged from 5.5% (NGRCO 9571) to 24.3% (NGRCO 9575), while fruit damage ranged from 0.0% (NGRCO 9572) to 18.2% (NGRCO 9570). Notably, NGRCO 9572 showed no fruit damage, while NGRCO 9573 and NGRCO 9581 exhibited minimal fruit damage (0.6% each). High-yielding cultivars (NGRCO 9579, NGRCO 9568) were moderately to heavily damaged, suggesting trade-offs between productivity and resistance, The resistant genotypes identified, particularly NGRCO 9572, NGRCO 9573, and NGRCO 9581, represent valuable genetic resources for integrated pest management and resistance breeding programmes against T. absoluta in Nepal.