Abstract: 【Aim】 To identify the pollinating insect resources in Nanchong City, Sichuan Province, Southwest China, study the local plant-insect pollination network, and assess the pollination service values provided by pollinating insects to major pollinating crops in the city and their contribution to agricultural productions.【Methods】Random net collection and sampling were used to investigate pollinating insect resources and construct pollination network during 2021-2022. The dependence degree of crops on insect pollination was determined through bagging isolation test, and the pollination service value and economic contribution rate of pollinating insects were evaluated based on relevant agricultural and forestry economic data of Nanchong City in 2020.【Results】 During 2021-2022, 79 species of pollinating insects belonging to 18 families and 50 genera, 59 species of pollinating crops and wild nectar plants belonging to 20 families and 50 genera were investigated in Nanchong City. The pollination network was characterized by low connectivity, medium nesting and low network specialization. In 2020, the pollination service value of pollinating insects in Nanchong City was about 3 325 017 600-5 072 791 200 Yuan RMB accounting for about 8.45%-12.88% of the gross value of agricultural production of that year. 【Conclusion】 Abundant pollinating insect resources in Nanchong City can provide sufficient pollination service for the production of vegetables, fruits and oil crops in Nanchong City. The characteristics of crop pollination network in Nanchong City are obvious. Pollinating insects could maintain the stability of ecosystem and plant species diversity. Major pollinating crops are highly dependent on insect pollination and there is a close relationship between agricultural production and pollinating insects. Protecting pollinating insect resources helps to ensure agricultural production and maintain the stability of wild plant communities in Nanchong City.

Key words:  Pollinating insects, pollination network, dependence degree of pollination, pollination service value