Impact of Selected Insect Pollinators on Yield and Physicochemical Quality of Apricot (Prunus armeniaca L.) and Apple (Malus domestica Borkh) in Doda District, Jammu and Kashmir (UT), India

Background: Insect-mediated pollination is an indispensable ecosystem service for temperate fruit crop production. Objectives: This study tested the hypothesis that insect pollinators make a quantifiable, irreplaceable contribution to the fruit set and physicochemical quality of apricot (Prunus armeniaca L., cv. Halman and cv. Chuli) and apple (Malus domestica Borkh., cv. Red Delicious and cv. Ambri) in Doda district, Jammu and Kashmir (UT), India. Materials and Methods: Three pollination treatments were implemented across replicated orchard sites during the 2023 and 2024 spring flowering seasons: open pollination (natural insect visitation), self-pollination under mechanical exclusion (nylon netting), and hand cross-pollination (positive control). Pollinator visitation was recorded using standardized timed focal sampling from anthesis until flowering cessation, and a Pollinator Importance Value (PIV) was calculated for each taxon. Fruit set percentage was determined at 30 days post-anthesis, and physicochemical parameters including fruit weight, volume, Total Soluble Solids (TSS), Titratable Acidity (TA), ascorbic acid content, and colorimetric indices (L*, a*, b*) were measured at commercial maturity. Results: Open-pollinated flowers achieved significantly higher fruit set than mechanically excluded self-pollinated flowers in both apple (72.4±4.2% vs. 18.3±2.7%; p<0.001; Cohen’s d=2.84) and apricot (64.7± 5.1% vs. 21.6±3.3%; p<0.001; d=1.97). Open-pollinated fruits were significantly heavier, had greater volume, and higher TSS and ascorbic acid content. Apis mellifera and Apis cerana dominated the pollinator community (PIV=0.338 and 0.243, respectively), with peak visitation between 10:00 and 14:00 hr. Pollinator visitation frequency was positively correlated with fruit set (r=0.82), fruit weight (r=0.74), and seed number per fruit (r=0.77). Conclusion: These findings establish insect pollinators as critical determinants of horticultural productivity in Doda district and provide an evidence base for pollinator conservation policy in J&K (UT).