# Ecological Interactions Between Camellia oleifera and Insect Pollinators Across Heterogeneous Habitats

## TL;DR

This study explores how Camellia oleifera interacts with insect pollinators in different habitats, identifying key pollinators and floral traits that influence pollination success.

## Contribution

The study identifies Apis cerana and Phytomia zonata as key pollinators and highlights stamen length as a critical floral trait influencing pollinator behavior.

## Key findings

- Apis cerana and Phytomia zonata were the most frequent pollinators of Camellia oleifera.
- Stamen length was found to be the main floral trait affecting insect populations.
- Phytomia zonata showed resilience to nectar toxicity and contributed significantly to pollination.

## Abstract

Camellia oleifera is an important woody oil plant in southern China. However, owing to a sharp decline in the number of wild pollinators, there are great limitations to the pollination and fruiting of C. oleifera. Therefore, it is important to evaluate the adaptations of insect pollinators to the pollination biological characteristics of C. oleifera. We investigated the flowering process, floral characteristics, and other biological traits of C. oleifera and analysed the differences in the types and quantities of flower-visiting insects in different habitats. By combining the characteristics of insect population and pollination behaviour, dominant pollinators varied by habitat, with Apis cerana and Phytomia zonata being the most frequent. Stamen length was an important factor for flower-visiting insects, and recommendations were presented for the protection of C. oleifera pollinators.

Camellia oleifera is an important woody oil plant in southern China, and developing its industry can enhance forest resource uses and increase edible oil supply. This study investigated the floral characteristics of different C. oleifera varieties, analysed the species and diversity of flower-visiting insects in different habitats, identified the main pollinators and their flower-visiting behaviours, and explored the relationship between pollinating insects and their floral characteristics. The floral lifespan of individual C. oleifera flowers was 5–8 d across cultivars, which is essentially the same. However, floral traits and nectar sugar composition exhibited distinct differences. There were 22 species of insect pollinators from 14 genera and 8 families, including Hymenoptera and Diptera, in 3 habitats. High-potential pollinators varied by habitat, with Apis cerana and Phytomia zonata being the most frequent. A comparison showed that A. cerana was the best pollinator, whereas P. zonata had a larger population, was not affected by oil tea nectar poisoning, and could still pollinate. Therefore, the contribution of P. zonata cannot be overlooked. Redundancy analysis revealed the response relationship between the floral traits of C. oleifera and three insect population characteristics. Stamen length was the main floral trait affecting insect populations.