Integrative Morphometric and DNA Barcoding Analysis of Insect Pollinator Diversity in Apple Orchards of the Kashmir Valley, India

Abstract

Pollinators play a vital role in enhancing apple productivity and maintaining ecosystem stability. In the Kashmir Valley, a prime apple-growing region of India, the horticulture sector is a cornerstone of the economy, making effective pollination services not just an ecological concern but a critical socio-economic factor. This study investigated the diversity, abundance, and morphometric variation of key insect pollinators in apple orchards across three districts of the Kashmir Valley, Baramulla, Srinagar, and Shopian representing varying altitudinal and ecological conditions. Surveys were conducted in apple orchards located in three districts of the Kashmir Valley, Baramulla, Srinagar, and Shopian, during peak apple flowering (April–May 2024). Morphological identification was complemented with DNA barcoding using COI gene sequences to confirm species identity. The dominant pollinators recorded were Apiscerana, Apis mellifera, Bombus sp., and Eristalistenax. Morphometric analysis revealed significant interspecific and intraspecific variation in body size, wing length, and proboscis dimensions, suggesting local adaptation to altitude and floral structure. DNA barcoding confirmed species identity with 98–100% similarity to reference sequences in NCBI, validating morphological taxonomy. Pollinator abundance correlated positively with fruit set and quality attributes, including fruit weight, seed number, and shape index. These findings underscore the ecological importance of pollinator diversity for sustainable apple production in temperate Himalayan ecosystems.