Organic mulches in highbush blueberries alter beetle (Coleoptera) community composition and improve functional group abundance and diversity

Abstract

1 Horticultural practices may impact invertebrates in agroecosystems, particularly natural enemies. Impacts can be better understood by grouping organisms functionally or using morphological traits in addition to taxonomic determinations. 2 We compared the effects of mulch type (compost, pine needles, unmulched) and weeding strategy (weeded, unweeded) on beetle (Coleoptera) communities in highbush blueberries, focusing on early-season captures that reflected overwintering habitat. 3 Beetle diversity was similar between plot types, although functional grouping revealed differences as a result of mulching but not weeding. Predatory and granivorous Carabidae were most abundant in unmulched plots, mycetophages were most abundant in pine needles, and saprophages were most abundant in compost. Predatory Staphylinidae were most diverse in compost plots, and the diversity of granivores was greatest in unmulched plots. 4 Carabid biomass was greater in unmulched than compost mulched plots partly as a result of larger beetle size. 5 Beetle communities in unmulched and pine needles mulched plots were more similar than those in compost mulched plots. 6 A combination of compost mulched and unmulched areas should benefit all predatory taxa, although mulch use for pest control will need to be evaluated within the context of other production goals.

Organic mulch can suppress litchi downy blight through modification of soil microbial community structure and functional potentials

“…As one important management practice in agricultural production, organic mulch is mainly used for soil improvement and environmental protection. The application of mulch derived from plant residues could not only increase water infiltration [ 11 ], prevent soil nutrient loss [ 12 ] and suppress weed germination [ 13 ], but also control crop pests and diseases [ 14 , 15 ] and increase the biodiversity of soil microecosystem [ 16 ]. Previous studies have reported strong changes in richness and diversity of soil microbial community regulated by organic mulch in vegetable and tea plantation [ 17 , 18 ].…”

Mulches Used in Highbush Blueberry and Entomopathogenic Nematodes Affect Mortality Rates of Third-Instar Popillia japonica

“…From a recent survey, 7 of 8 highbush blueberry growers in Ontario, Canada, applied a mulch every 2-3 years of chipped wood pallets, sawdust with manure from horse barns, pine bark, sawdust, wood shavings or discarded peat moss [18]. Using compost or a compost and mulch mix also improved plant growth and yield [17], provided pest control, and benefitted natural enemies [19,20]. Composts may also improve the virulence of and pest mortality rates caused by EPNs compared to certain soil types [21], although immaturely-cured compost may negatively affect EPN virulence [22].…”