Benefits of increased cover crop diversity for predators and biological pest control depend on the landscape context

Abstract

1. Increasing plant diversity in agricultural systems is a promising way to balance food production and biodiversity conservation. Biological pest control, a crucial ecosystem service delivered by natural enemies, could particularly benefit from increased plant diversity at the local scale. Such positive effects however often depend on the landscape context that shapes the pool of natural enemy species available and their ability to colonize newly created habitats. However, how the landscape context modulates the local effect of plant diversity on natural enemies and pest control services remains unclear.2. Here, we manipulated the diversity of cover crops (2 versus 20 plant species) in nine pairs of vineyards located along a landscape gradient ranging from 20 to 60% of semi-natural habitats. We sampled natural enemy communities in the soil and foliage and measured the predation rate of an important moth pest in European vineyards (Lobesia botrana).3. Diverse cover crops enhanced the abundance of natural enemies by 140% across the experiment, but without changing their taxonomic richness and composition.We further found a distance-decay effect of cover crops on natural enemy abundance across cover crop types. 4. The landscape context remarkably modulated the effects of local plant diversity on natural enemy abundance and predation rates. While predation rates were on average similar in the low and high cover crop diversity treatments across the experiment, diverse cover crops had higher positive effects on predation and natural enemies in simple (<50% semi-natural habitats) than complex landscapes. Predation rates increased from 11 to 42% in the high compared with low cover crop diversity treatments in simple landscapes. Synthesis and applications:Our study demonstrates the benefits of increasing plant diversity at the local scale to enhance the abundance of natural enemies as well as the level of biological pest control services in vineyard agroecosystems. Diverse cover crops mostly benefit natural enemies and biological pest control in simplifiedThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Nature‐based Solutions to tackle climate change and restore biodiversity

“…This positive relationship between biodiversity and ecosystem functioning is shown by Beaumelle et al. (2021) in their contribution to this Special Feature. This study demonstrates the advantages of increasing plant diversity on a local scale to improve biological pest control services, using vineyards as the test crop habitat due to its high use of pesticides.…”

“…Some of these ecosystem functions are also particularly relevant for humans; for instance, it is estimated that animals pollinate two-thirds of all crops grown for human consumption (Klein et al, 2007). This positive relationship between biodiversity and ecosystem functioning is shown by Beaumelle et al (2021) in their contribution to this Special Feature. This study demonstrates the advantages of increasing plant diversity on a local scale to improve biological pest control services, using vineyards as the test crop habitat due to its high use of pesticides.…”

“…As this Editorial has shown, targeting diverse and natural habitats with NbS may not guarantee the best outcome of an ecosystem service. The benefits of diversifying flora for natural pest control were most effective in simple, manipulated habitats (Beaumelle et al., 2021), although desirable characteristics such as terrestrial carbon storage is greater in more complex habitats (Kaarakka et al., 2021).…”

Effects of green manure planting mode on the quality of Korla fragrant pears (Pyrus sinkiangensis Yu)

“…The market value of fragrant pear is closely related to the size, shape, texture, nutrition and flavor of the fruit. In addition, in the process of orchard management, cover crops between fruit tree rows will form a small ecological circle on the surface, which is conducive to maintaining water and promoting nutrient cycling ( Yuarsah and Handayani, 2017 ), and also effectively inhibits the erosion of main crops by pests ( Bowers et al., 2020 ; Beaumelle et al., 2021 ). Therefore, the screening of orchard cover crops should be based on fruit quality, and then combined with the actual requirements of agronomy to carry out evaluation, in order to determine the suitable cover crops for orchard, and better play the advantages of green manure.…”

Effects of Ground Cover Management, Landscape Elements and Local Conditions on Carabid (Coleoptera: Carabidae) Diversity and Vine Vitality in Temperate Vineyards

“…Attributes of vegetation physical architecture, above and below ground, also provide alternative food and shelter for arthropods and mesofauna [21][22][23]. More specifically, ground cover vegetation in perennial systems is seen to increase the abundance of natural enemies [24] as well as influence herbivorous pest species, natural enemies and their interactions in vineyards, depending also on the landscape context [25,26]. Flower-rich cover-crop mixtures in vineyards are expected to increase the abundance of a range of natural enemies, including carabids [27][28][29].…”