Interactions of flower visitors with bitter gourd (Momordica charantia L.) and effects of right target and wrong target flower visits on plant reproduction

TL;DR

This study explores how flower visitors interact with bitter gourd plants and how different types of visits affect pollination and plant reproduction.

Contribution

The study identifies the role of 'wrong target' visits in pollination, which has been previously overlooked.

Findings

Apis cerana and other bee species were found to be the most effective pollinators of bitter gourd.

Wrong target visits still contributed to significant pollen deposition and successful fruit and seed production.

Most flower visitors, especially bees, made both right and wrong target visits to female flowers.

Abstract

Studying flower visitors, visitation patterns, and pollinator effectiveness can provide valuable insights into the interactions between plants and pollinators. Bitter gourd (Momordica charantia), a key vegetable crop, relies on flower visitors, especially pollinators. However, the specific role of wild pollinators and the impact of different visit types on bitter gourd pollination remain unclear. We aimed to uncover plant–pollinator interactions on the crop species. We recorded the flower visitors and their visitation patterns, categorising visits as right target when the visitor collected floral resources, and as wrong target when the visitor did not collect any resources from the flowers. We also determined the impacts of two types of flower visits on plant reproduction based on pollen deposition and the resulting fruit and seed sets after a single visit by different pollinators. Several insect species visited bitter gourd flowers, while the most abundant and effective pollinators (based on the pollination service index, PSi) were Apis cerana, Apis dorsata, Apis florea, Austronomia ustula, Lasioglossum albescens, Lasioglossum cavernifrons, Lasioglossum funebre, and Nomia (Hoplonomia) elliotii. Most visitors, especially bees, made both the right target and the wrong target visits to female flowers. In addition to the right target visits, pollinators deposited significant pollen grains on flower stigmas via wrong target visits, leading to fruit and seed sets. These findings highlight the overlooked yet crucial role of wrong target visits in pollination and reproductive success.

The online version contains supplementary material available at 10.1038/s41598-025-20968-w.

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