Contribution
Harnessing functional intercropping: sorghum - cotton systems enhance biological control and boost yield
Cui, Hongying; Ma, Guangmin; Wang, Zhongmin; Li, Yaofa; Li, Lili; Song, Yingying; Guo, Wenxiu; Lv, Suhong; Men, Xingyuan; Ouyang, Fang
Entomologia Generalis Volume 46 Number 1 (2026), p. 89 - 97
publié: Mar 31, 2026
publication en ligne: Jan 15, 2026
manuscrit accepté: Nov 19, 2025
révision final du manuscrit reçu: Sep 21, 2025
révision du manuscrit demandée: Aug 29, 2025
manuscrit reçu: Apr 24, 2025
ArtNo. ESP146004601009, Prix: 29.00 €
Abstract
Intercropping is a promising agroecological strategy that enhances biodiversity and offers sustainable pest control. This study proposes an innovative sorghum–cotton intercropping system that utilizes the ecological functions of sorghum to conserve high densities of aphidophagous lady beetles. We hypothesize that sorghum serves as an early-season refuge and nutritional resource for natural enemies, thereby enhancing the biocontrol of cotton aphids and ultimately increasing cotton yield. We used stable carbon isotope (δ13C) to investigate the trophic interactions and dispersal dynamics of lady beetles, Propylaea japonica and Harmonia axyridis (Coleoptera: Coccinellidae), during four years of field trials. Our results showed that δ13C values for P. japonica and H. axyridis collected from cotton and sorghum fields ranged from −17.11‰ to −15.01‰ on 10-Aug, and from −20.12‰ to −18.17‰ on 15-Sep. Isotopic signatures indicated that both lady beetles initially fed on sorghum aphids before shifting to cotton aphids as the season progressed. Sorghum–cotton intercropping systems of 1:4 and 1:8 planting patterns significantly reduced cotton aphid densities below economic thresholds and concurrently increased predator abundance and cotton yield per unit area. Notably, seed cotton weight increased by up to 37.26% under the 1:8 pattern compared to monoculture. Our findings demonstrate that sorghum–cotton intercropping, specifically at 1:4 and 1:8 ratios, provides a viable strategy for reducing pest pressure, conserving natural enemies, and increasing yield, thereby reducing dependency on pesticides. Thus, this integrative approach presents a practical pathway for achieving the critical multiple goals of improved biological control, pesticide reduction and enhanced agroecosystem sustainability.
Mots-clefs
Coccinellidae •
aphid •
Propylaea japonica
•
Harmonia axyridis
•
crop yield •
carbon stable isotope (δ13C) •
sorghum-cotton intercropping system •
economic threshold •
pesticide reduction