Article
Pollination by native bees achieves high fruit quantity and quality of highbush blueberry: a sustainable alternative to managed pollinators
Autor
Cortés-Rivas, Benito
Monzón-Godoy, Víctor
Ordones Rego, Juliana
Mesquita-Neto, José N.
Institución
Resumen
Introduction: Blueberry is one of the most relevant buzz-pollinated crops
worldwide, and Chile is the most important global producer of fresh blueberries
during wintertime in the Northern Hemisphere. Non-buzzing bees, such as
honey bees, may provide suboptimal services compared with bees capable
of buzz pollination. The widely held contention that honey bees are inferior
pollinators of blueberries drives the industry to place pressure on governments
to allow bumblebee (Bombus terrestris) importation for pollination. However,
the introduction of B. terrestris generates environmental problems in Chile by
competing with and transmitting parasites to local bees. Despite some native
Chilean bees being recently recognized as e cient pollen vectors of blueberry
crops, no study has evidenced the influence of their visits on fruit yield. Therefore,
we aimed to evaluate the native Chilean floral visitors’ performance to improve the
quantity and quality of highbush blueberry in comparison to the performance of
managed visitors.
Methods: Per-visit pollination performance (fruit set and fruit quality) and visitation
frequency were measured, and the performance of buzzing behavior by flower
visitors was evaluated in four cultivars grown in five blueberry orchards located in
southern Chile.
Results: We found that fruit set and weight were highly influenced by floral visitor
taxon. Some native bee species can greatly improve the fruit set and fruit quality
(greater weight) of the highbush blueberry cultivars. For instance, one single visit
of C. occidentalis can increase fruit weight by a factor of 1.8 compared to an
A. mellifera visit; however, visits of halictids and syrphids resulted in lower fruit
sets than those of unvisited flowers. However, we found that the occurrence of
sonication behavior alone was not a predictor of higher fruit set and fruit weight
of highbush blueberry cultivars. Consequently, the taxonomic recognition of floral
visitors, ideally to the species level, is still needed to distinguish the most e cient
fruit yield promoters of blueberry.
Discussion: The conservation of the biotic pollinators, especially native
pollinators, would improve blueberry fruit quality and is likely to improve overall
crop productivity.