Effects of strip intercropping of canola with faba bean, field pea, garlic, or wheat on control of cabbage aphid and crop yield

Abstract

The impacts of intercropping of canola (Ca) with faba beans (Fb), field peas (Fp), garlic (G), or wheat (Wh) were evaluated on the cabbage aphid, Brevicoryne brassicae (Linnaeus, 1758), natural enemies and canola yields in row ratios of 3Ca : 3Fb, 3Ca : Fp, 3Ca : 3G, and 3Ca : 3Wh in 2018 and 2019. In both years, the lowest aphid population was recorded in 3Ca : 3G. In 2018, the aphid population was significantly (P < 0.05) lower in 3Ca : 3Fp than in the monoculture, while, in 2019, it was lower in the intercrops compared to the monoculture. Furthermore, none of the intercrops, except 3Ca : 3Fb, showed a significant increase in the predator diversity and parasitism rate. The dry seed weight loss was higher in the monoculture and 3Ca : 3Wh than in the other intercrops. Based upon the obtained results, decreasing the density of the cabbage aphid and increasing the canola yield by intercropping canola with the faba bean, the field pea or garlic is possible with this system. The inferences of these outcomes, which are associated with the integrated pest management (IPM) in canola cropping systems, are discussed.

Keywords

• brassica napus
• brevicoryne brassicae
• intercropping
• parasitism
• predators
• species diversity