Ground cover vegetation promotes biological control and yield in pear orchards

Abstract

The use of ground cover vegetation is becoming a prominent way of promoting biodiversity and associated ecosystem services in Chinese orchards. Despite the large number of studies that have addressed the effects of ground cover vegetation on promoting natural enemy populations and related pest control, it is still unclear whether enhanced natural pest control can increase yield and reduce the use of pesticide. We performed an experiment comparing three cover vegetation practices (ryegrass, clover and hairy vetch) versus a bare ground control in commercial pear orchards in the Yangtze River Delta of East China (YRDEC), China. Natural enemy density (predator and parasitoid abundance), invertebrate herbivore performance (piercing‐sucking herbivore abundance and branch‐boring and fruit‐boring percentage), pesticide input, and pear fruit yield were recorded. The results indicated that cover vegetation decreased herbivore abundance and boring percentage by 50% and 64%, respectively, thus decreasing pesticide use by 26%. We also found that cover vegetation increased the abundance of natural enemies by 621%, and increased pear fruit yield by 7%. Piecewise structural equation modelling confirmed that increased natural enemy densities, decreased herbivore performance by 102%, pesticide use by 51% and increased fruit yield by 10%. This study suggests that the use of ground cover vegetations, especially with clover and hairy vetch, is an effective way of promoting biocontrol services and associated ecosystem services in pear orchards.

Ecosystem services of organic versus inorganic ground cover in peach orchards: A meta‐analysis

“…Similarly, meta‐analysis studies have indicated that the abundance of plant species promotes pest regulatory services by enhancing predator and parasitoid abundance, predation, and parasitism (Wan et al, 2021). Field studies in orchard management revealed that organic GC boosted fruit yield by 10% while decreasing pesticide use by 51% (Ji et al, 2022). In addition, using border crops in urban agriculture has shown that insecticide use reduced while crop yields increased (Wan, Cai, et al, 2018).…”

Mite fauna (Acari) associated with apple orchards (Malus domestica) and spontaneous vegetation as reservoir for predatory mites

“…Thus, it can be stated that the maintenance of spontaneous vegetation in orchards favors the permanence of predators, acting as a refuge and reservoir for these natural enemies (Altieri 1999, Prischmann & James 2003. Certain plants associated with orchards play an important ecological role as they are hosts of species that help in the biological control of agricultural pests, as they naturally migrate from this spontaneous vegetation to the main crop of the orchard (Tixier et al 2000, Lykouressis et al 2008, Ji et al 2022). These plants can provide shelter and food, such as pollen, for predatory mites, keeping them in these areas even in periods with unfavorable abiotic conditions or when there is a shortage of prey (Landis et al 2000, Tixier et al 2000, Demite & Feres 2005, assisting in the colonization of these areas through aerial dispersal (Tixier et al 2000, Jung & Croft 2001.…”

“…The morphology of some of these plants consists of trichomes, domatia and nectaries, which are beneficial structures for the plant and offer refuge, a safe place for oviposition and provide alternative foods such as pollen and nectar to mite species (Agrawal & Karban 1997, Ferla & Moraes 2002, Prischmann & James 2003, Matos et al 2006, Duso et al 2010. Certain plants, associated with orchards, play an important ecological role as they host species that help in the biological control of agricultural pests, as they naturally migrate from this spontaneous vegetation to the main crop of the orchard (Tixier et al 2000, Altieri 2002, Kreiter et al 2003, Lykouressis et al 2008, Ji et al 2022.…”

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].…”