Proximity to forest edge does not affect crop production despite pollen limitation

Area of Science:

• Ecology
• Agricultural Science
• Conservation Biology

Background:

• Agriculture expansion and intensification negatively impact pollination services.
• Pollinator visits to grapefruit crops in northwest Argentina decrease significantly with distance from forest edges.

Purpose of the Study:

• To assess if reduced pollinator visits affect grapefruit pollination services.
• To analyze pollen deposition, pollen tube growth, and fruit production in relation to distance from forest remnants.
• To evaluate the quantitative and qualitative efficiency of honeybees as pollen vectors.

Main Methods:

• Measured pollen receipt on stigmas and pollen tubes in styles at varying distances from Yungas forest.
• Assessed fruit production and conducted pollen supplementation experiments (self- and cross-pollen).
• Examined honeybee efficiency in pollen deposition and its impact on fruit development.

Main Results:

• Pollen receipt and pollen tube growth decreased with increasing distance from the forest edge.
• Fruit production was not affected by distance, but pollen quantity and quality were identified as limiting factors.
• Honeybees did not consistently deposit sufficient high-quality pollen for optimal fruit development, indicating a qualitative limitation.

Conclusions:

• Preserving forest remnants is crucial for maintaining pollinator populations and ensuring crop production resilience.
• Pollen limitation in crops can result from both pollinator scarcity and poor pollination quality, emphasizing pollinator efficiency over mere abundance.