Screening Apple and Apricot Cultivars for Resistance against Key Insect Pests in Trans Himalayan Region

Abstract

Apricot (Prunus armeniaca L.) and apple (Malus domestica Borkh.) are the most widely cultivated fruits in Ladakh, but their production is increasingly threatened by insect pests like aphids and codling moths (Cydia pomonella). This study aimed to evaluate the resistance of three popular apricot varieties Halman, Raksteykarpo, and Narmo to aphid infestations, and three apple varieties Tha-kushu, Mongol, and Phemar-khushu to codling moth damage. Field surveys were conducted in orchards across the Leh district during the 2022 and 2023 growing seasons to assess pest incidence and varietal response. The results showed that Halman was the most susceptible to aphids among apricots, with an infestation rate of 47.76%, followed by Raksteykarpo (38.44%). In contrast, Narmo exhibited the lowest infestation (23.11%) and demonstrated moderate resistance. Similarly, in apples, Tha-kushu suffered the highest fruit damage from codling moths (55.49%), followed by Mongol (36.66%), while Phemar-khushu experienced the least damage (26.83%), likely due to its early maturation, which limited its exposure to multiple pest generations. These findings underscore the importance of selecting pest-tolerant cultivars for sustainable fruit farming in Ladakh. While none of the varieties was entirely resistant, Narmo and Phemar-khushu showed promising levels of tolerance, making them more suitable for cultivation in pest-prone regions. As climate change continues to impact pest dynamics, further research on plant resistance traits and eco-friendly pest management strategies is crucial. Identifying naturally resilient cultivars will not only support breeding programs but also help local farmers adopt sustainable agricultural practices while reducing reliance on chemical pesticides.