# Species Identification, Insecticide Resistance and TYLCV Detection of Bemisia tabaci in Kashgar, Xinjiang

## TL;DR

This study examines Bemisia tabaci in Kashgar, finding high insecticide resistance and TYLCV prevalence, which threatens tomato and cotton crops.

## Contribution

The study provides updated resistance profiles and virus detection rates for Bemisia tabaci in Kashgar, guiding sustainable pest management.

## Key findings

- All tested Bemisia tabaci individuals were identified as the Mediterranean (MED) cryptic species.
- Imidacloprid and pyridaben showed extreme resistance, while nitenpyram and a mixture of emamectin benzoate–chlorantraniliprole remained effective.
- 97.5% of Bemisia tabaci adults from tomato greenhouses were infected with TYLCV.

## Abstract

Rapid development of insecticide resistance in Bemisia tabaci poses serious threats to key crops such as tomato and cotton. In this study, populations collected from cotton and tomato fields in Kashgar in 2024 were examined for species identification, insecticide susceptibility, and tomato yellow leaf curl virus (TYLCV) infection. Molecular identification revealed that all successfully tested individuals belonged to the Mediterranean (MED) cryptic species. Bioassays with 13 insecticides showed that neonicotinoids, including imidacloprid, had lost effectiveness due to high resistance levels, whereas nitenpyram and the emamectin benzoate–chlorantraniliprole mixture retained strong efficacy. Approximately 98% of the Bemisia tabaci individuals collected from tomato plants were positive for TYLCV, indicating a high potential for virus transmission within tomato crops. These findings provide critical insights into the resistance status, species identification, and virus-carrying capacity of B. tabaci in Kashgar, offering guidance for sustainable pest management strategies in key crops.

The rapid evolution of insecticide resistance in Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) threatens effective pest management in key crops. This study characterized B. tabaci populations from cotton and tomato fields in Kashgar (September–October 2024) using mtCOI-RFLP for cryptic species identification, leaf-dip bioassays with 13 insecticides, and PCR detection of tomato yellow leaf curl virus (TYLCV). All analyzed individuals belonged to the Mediterranean (MED) cryptic species. Extreme resistance was observed to imidacloprid (RR = 320.65) and pyridaben (RR = 331.29), while nitenpyram (RR = 1.77) and the emamectin benzoate–chlorantraniliprole mixture (RR = 2.13) remained effective. TYLCV was detected in 97.5% of adults from tomato greenhouses. These findings provide a concise assessment of resistance status, species identification, and virus prevalence in B. tabaci, informing sustainable management strategies in cotton and tomato production.