Flower strips can promote natural enemy biodiversity and biocontrol services, and prevent pest resurgence in cotton crops

Authors: YANG, QUANFENG - Chinese Academy Of Sciences; MEN, XINGYUAN - University Of Chinese Academy Of Sciences; ZHANG, KENING - Chinese Academy Of Sciences; LIU, MIN - Bureau Of Agriculture And Rural Affairs Of Wucheng County; GUO, WEI - Bureau Of Agriculture And Rural Affairs Of Wucheng County; ZHU, CHUNGUANG - Bureau Of Agriculture And Rural Affairs Of Wucheng County; ZHAO, WENLU - Dezhou Academy Of Agricultural Sciences; Reddy, Gadi V.P.; OUYANG, FANG - Chinese Academy Of Sciences; GE, FENG - Chinese Academy Of Sciences

Submitted to: Entomologia Generalis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/12/2022
Publication Date: 10/28/2022
Citation: Yang, Q., Men, X., Zhang, K., Liu, M., Guo, W., Zhu, C., Zhao, W., Reddy, G.V., Ouyang, F., Ge, F. 2022. Flower strips can promote natural enemy biodiversity and biocontrol services, and prevent pest resurgence in cotton crops. Entomologia Generalis. 42:1-12. https://doi.org/10.1127/entomologia/2022/1545.
DOI: https://doi.org/10.1127/entomologia/2022/1545

Interpretive Summary: Conservation biological control can be improved by enhancing the temporal stability of the intensity of the biological control processes. Natural enemies, including predatory beetles, bugs, lacewings and hoverflies, were greatly increased in flower strips themselves. Strong reductions were found in cotton aphids (59%) and plant damage caused by cotton aphids (60%) in fields with flower strips compared with untreated control fields. The resurgence of cotton aphids in pesticide-treated cotton fields occurred in the second aphid peak and the period of declining aphid abundance in the untreated control fields. During these periods, aphid abundance and plant damage in flower strip fields were reduced by 82% and 40% compared with pesticide-treated fields.

Technical Abstract: Repeated use of pesticides in cotton can damage wildlife and the environment, and may trigger pest resurgence. To develop more sustainable pest management strategies, we examined three management strategies for cotton aphids in China: (1) sown borders of flower strips, (2) chemical control using imidacloprid, and (3) no pesticide applications and no border flower strips (the untreated control). Under all three management types, we monitored natural enemy diversity, pest abundance, and cotton plant damage. We found that flower strips enhanced both the density and specie number of aphid predators, including ladybeetles, predatory bugs, lacewings, and hoverflies. The progression of populations of cotton aphids in untreated control fields was divided into the initial period, first peak abundance period, second peak abundance period, and the period of aphid decline. We found strong reduction in cotton aphids (59%) and plant damage caused by cotton aphids (60%) in cotton fields with flower strips compared with untreated control fields. Cotton aphid resurgence occurred in pesticide-treated fields in the second peak period and the decline period. During these periods, aphid abundance and plant damage in fields with flower strips were reduced by 82% and 40% compared with pesticide-treated fields. Also, aphid abundance and plant damage in fields with flower strips were reduced by 71% and 60% compared with untreated control fields. Our study demonstrates a high degree of effectiveness of flower strips in promoting natural enemy biodiversity, biocontrol services, and averting pest resurgence in cotton crops.