Original paper
Intercropping cotton with maize enhances biological control of aphids by the predatory lacewing Chrysoperla sinica
Wang, Mingyi; Zhang, Feng; Su, Yuan; Hui, Cang; Ge, Feng; Zhang, Yongsheng; Ouyang, Fang
Entomologia Generalis Volume 46 Number 1 (2026), p. 121 - 131
published: Mar 31, 2026
published online: Jan 28, 2026
manuscript accepted: Nov 29, 2025
final revised version received: Nov 24, 2025
manuscript revision requested: Oct 8, 2025
manuscript received: Jun 19, 2025
Open Access (paper may be downloaded free of charge)
Abstract
Natural enemies play a vital role in integrated pest management by regulating agricultural pests through predation. Chrysoperla sinica (Tjeder) (Neuroptera: Chrysopidae) is a generalist predator known for suppressing aphid populations and contributing to sustainable pest control in cropping systems. The structure of agricultural landscapes can influence the distribution and effectiveness of these beneficial insects. Intercropping – growing two or more crops together – is a common practice that enhances habitat complexity and resource availability for natural enemies. Despite its importance, little is known about how intercropping affects the oviposition behaviour and habitat preference of lacewing adults. This study investigated how agricultural landscapes structure (Crop type, Crop area and Landscape shape index) and aphid density influence the density of the predatory lacewing, Chrysoperla sinica in a cotton-maize agroecosystem, Northern China, using data from three consecutive years of field surveys. Results showed that densities of lacewing egg, and larva were higher on cotton in 2009 and 2010 whereas adult densities were greater on maize during much of the growing season (August 9 2009, Δ = −0.186; July 4 2010, Δ = −0.427). The impact of crop area on lacewing density was infrequently observed. Lacewing egg densities in 2009 (β = 19.354) and adult densities in 2010 (β = 0.513) were positively correlated with aphid density on cotton. Lacewing egg densities in 2009 (β = 3.410) and adult densities in 2010 (β = 1.403) on maize was positively driven by landscape shape index. Lacewings preferred to lay eggs in cotton fields or in maize patches adjacent to cotton. While the adult lacewings primarily resided in maize – especially in fields with more cotton edges – they actively migrated to cotton patches to forage for aphids. Thus, maize can act as a suitable habitat for lacewings, supporting their persistence in the landscape and enhancing aphid suppression in nearby cotton fields.
Keywords
agricultural landscape • integrated pest management (IPM) • Bt cotton • agroecology • crop diversity • conservation biological control • edge effect • sustainable pest management