# Seasonal abundance of six tephritid species and the fruiting phenology of their main hosts in northern Jiangxi, China

## TL;DR

This study tracks the seasonal activity of six invasive fruit fly species and their host plants in northern Jiangxi, China, to help manage their impact on agriculture.

## Contribution

The study reports the first discovery of Bactrocera minax and Callantra trimacula in northern Jiangxi and provides detailed seasonal abundance and host preferences.

## Key findings

- B. minax and C. trimacula were newly recorded in northern Jiangxi.
- Zeugodacus tau had the highest population density among the six species.
- Different tephritid species showed distinct seasonal peaks and host plant preferences.

## Abstract

Several tephritid species have successfully invaded northern Jiangxi, China, posing a serious threat to regional fruit and vegetable production. This study presents a detailed report on the seasonal abundance of six tephritid species and the fruiting phenology of their main hosts across Nanchang, Yongxiu and Xiushui in northern Jiangxi from 2018 to 2021, using data from methyl eugenol (ME), cuelure (CUE), and sugar-wine-vinegar-water (SWVW)-baited traps and from fruits infested by tephritid larvae. A total of 18,875 tephritid specimens were captured by traps, representing six species, Bactrocera dorsalis (Hendel), B. scutellata (Hendel), B. minax (Enderlein), Zeugodacus tau (Walker), Z. cucurbitae (Coquillett), and Callantra trimacula (Wang). Notably, B. minax and C. trimacula were discovered for the first time in northern Jiangxi. In addition to B. minax (captured only in Xiushui) and Z. cucurbitae (captured only in Nanchang), B. dorsalis, B. scutellata, Z. tau and C. trimacula were captured in all three regions. Zeugodacus tau exhibited the highest population density, followed by B. dorsalis and B. scutellata, and C. trimacula densities were markedly lower. The diversity index of captured tephritid species was similar in Nanchang, Yongxiu and Xiushui, but varied significantly across different seasons from May to December. When tephritid adults were active, B. minax population density reached its maximum in mid-June, whereas B. scutellata, Z. tau and Z. cucurbitae peaked in August–September, and B. dorsalis peaked in September–October. Bactrocera dorsalis and B. minax share similar hosts, primarily those from the Rutaceae family, including Citrus sinensis (L.) Osbeck, C. reticulata Blanco, C. maxima (Burm) Merr., and C. grandis Tomentosa. However, B. scutellata, Z. tau and Z. cucurbitae have similar hosts, especially those from the Cucurbitaceae family, such as Cucurbita moschata (Duch. ex Lam.) Duch.ex Poiret, Luffa cylindrica (L.) Roem., Momordica charantia L., and Cucurbita pepo L. The varying phenological stages of different host fruits guaranteed a continuous and adequate supply of suitable food resources for these tephritid species across different seasons. The theoretical and practical implications of the results concerning the management strategies for the six tephritid species in northern Jiangxi, China, are discussed.