Cultivar Mixture Enhances Crop Yield by Decreasing Aphids

Abstract

The reduction in biodiversity owing to agricultural intensification has brought negative effects on sustainable crop production in the agro-environment. Plant diversity can help regulate insect pests; however, research that demonstrates that genotypic diversity of multiple varieties with prominent agroecological practices to suppress insect pests and benefit crop yield at agricultural landscapes is limited. To examine the effects of diversity of wheat varieties on aphids and crop productivity, we performed field experiments by designing plots of single (resistant/susceptible) and cultivar mixtures in 2018–2020. The effects of population abundance of cereal aphids (Sitobion miscanthi and Rhopalosiphum padi) and crop yield on resistant and susceptible wheat varieties and mixture of wheat cultivars were determined to reveal the most dominant mixed broadcasting mode in Kaifeng of China. The results showed that cultivar mixture significantly decreased aphid abundance compared with the single varieties (resistant/susceptible). Cultivar mixture had a higher yield compared with the single varieties (resistant/susceptible). Additionally, cultivar mixture had significantly higher thousand-grain weights than susceptible and resistant wheat varieties in 2019 and 2020. Cultivar mixture enhanced wheat yield by decreasing cereal aphids, indicating a bottom-up or top-down effect from genetic diversity to pest abundance. Our results indicated that appropriate cultivar mixtures could manage insect pests to some extent and stabilize crop yield.

Journal of Water and Land Development

“…The use of a mixture of varieties instead of one variety as a method of controlling insects, such as aphids, is recommended by a number of scientists, as they note a decrease in the number of pests and an increase in crop yield [DUAN 2022;GRETTENBERGER, TOOKER 2017].…”

Cereal Aphid Parasitoids in Europe (Hymenoptera: Braconidae: Aphidiinae): Taxonomy, Biodiversity, and Ecology

“…The authors also found that predation in nonorganic (conventional) fields was higher than in organic fields within simple landscapes. In a recent study, the abundance of S. miscanthi and R. padi was decreased when five different varieties of winter wheat were sown in a field [241]. Different wheat genotypes can also determine aphid abundance.…”

Concepts of trait diversity – the key to effective IPM for resilience in arable systems?

“…This is shown very clearly in reduced Rhynchosporium infection in winter barley which is directly proportional to the number of components in the mixture, and greater component number leads to yield increase even in the absence of disease (Newton et al, 1997). Similarly, aphid abundance was lower in wheat cultivar mixtures, with no yield impairment (Duan et al, 2022). However, a small amount of particular varieties in an intra-specific mixture of plants can contribute a disproportionately large effect on the function of the mixture for some outcomes such as disease reduction (Newton and Skelsey, 2023), so the nature of such responses is likely to be trait specific.…”