# Flower-Visiting Insect Diversity Within Buckwheat Crops: An Underutilized Crop for Sustainable Economic Livelihoods

## TL;DR

Buckwheat crops attract diverse pollinators, which significantly boost yields and provide economic and nutritional benefits to rural communities in Nepal.

## Contribution

The study reveals the underappreciated role of non-honey bee pollinators in buckwheat production and quantifies the economic and nutritional impact of pollination.

## Key findings

- Flower-visiting insect communities varied significantly between two sites, independent of temperature and humidity.
- Insect pollination contributed over 70% to buckwheat yield and added USD 2.6 million in economic value.
- Non-Apis insects like flies and solitary bees played a significant role in pollination despite managed honey bee presence.

## Abstract

This study was carried out on Buckwheat, a pseudocereal crop, to examine the diversity of flower-visiting insects and their effects on the crop production at the two commercial sites of Chitwan District, Nepal. Overall, we found the 24 insect taxa and noted distinct variations in insect assemblages between sites, suggesting that regional ecological and landscape factors play a significant role. Over 70% of the buckwheat yield was due to the insect pollination. Although managed honey bees were present, frequent visits by flies and solitary bees indicate that non-Apis taxa make significant contributions to buckwheat pollination at local scales. The significant economic and nutritional benefits were brought to rural communities by insect-mediated pollination, which increased the availability of vital micronutrients for farming householdsand contributed about USD 2.6 million in production value. Our findings show that the decline in pollinators will cause substantial yield reductions, pose threats to the economy and food security through production losses, and reduce the nutritional value of agricultural products. These results highlight how necessary it is to implement conservation and management strategies that will aid both managed and wild insect pollinator species in and around agricultural production landscapes.

Buckwheat (Fagopyrum esculentum) is an important source of nutrition for humans, providing essential nutrients such as protein, fiber, vitamins, and minerals. Its cultivation is highly attractive to flower-visiting insects, which find abundant nectar and a moderate amount of pollen grains. This study aimed to characterize the taxonomic diversity and composition of flower-visiting insect communities in buckwheat crops across two sites in Chitwan district, Nepal and to assess whether temperature and relative humidity influence community structure. We further quantified the contribution of insect pollination to buckwheat yield by comparing pollinator-excluded plots (net-covered) with open-pollinated plots. In addition, we estimated the economic value of insect-mediated pollination and the nutritional contribution of buckwheat production on a per capita basis. Data were analyzed using non-metric multidimensional scaling, permutational multivariate analysis of variance, similarity percentage analysis, and (generalized) linear mixed-effects models. We found significant differences in flower-visiting insect community composition between the two study sites, independent of temperature and relative humidity, with twelve taxa contributing most to this dissimilarity. Open-pollinated plots exhibited higher buckwheat yields than pollinator-excluded plots, highlighting the importance of insect visitation for crop production. Despite the presence of managed Apis species, we recorded frequent visitation by flies and solitary bees, indicating that these taxa are likely important contributors to buckwheat pollination at local scales. Similarly, insect-mediated pollination significantly increased buckwheat production, and its absence would result in substantial economic losses of USD 2.6 million and reduced nutritional contributions, highlighting the vulnerability of buckwheat-based food security for the Nepalese communities due to pollinator decline.