A little-known world - assessing a non-bee crop flower visiting
community using metabarcoding
Abstract
Pollinator diversity is critical for optimal ecosystem service and
function. While bees are frequently the most efficient pollinators, they
represent only a small fraction of pollinator diversity. Non-bee
pollinators have received little recognition for their role in
commercial agricultural pollination despite representing 95% of flower
visitor diversity. Many non-bee pollinators are more resilient to
land-use intensification and climate change due to their nomadic
life-history and tolerance of inclement weather. Our research
characterizes non-bee pollinator communities, their foraging
preferences, and floral fidelity in strawberry crops. We caught 608
non-bee flower visitors, across three field sites, during three months
of the flowering period (May–August) of day-neutral strawberries in
southern Ontario. DNA metabarcoding provided species-level
identifications of the non-bee flower visiting community. Diptera (64%)
and Hymenoptera (22%) (primarily bee species) were the most abundant
flower visitors; Coleoptera and Hemiptera were also collected from
flowers. Metabarcoding of pollen identified pollen from 110 genera
representing 48 different families. Species with a high floral fidelity
(flower constancy) for visiting strawberries were likely to be more
effective pollinators (vectors of conspecific pollen between
reproductively receptive strawberry plants). Additionally, small amounts
of pollen from other plant genera suggested that insects are active and
mobile, rather than staying stationary on a single flower.