Work

The effect of drought stress on the limits and costs of plasticity in floral longevity in response to pollinator decline

Year: 2026

Type: article

Abstract: PREMISE: Declines in pollinator populations can reduce pollination services to plants, resulting in lower seed production. In response to these reductions, plants could increase the probability of pollinator visitation by plastically extending floral longevity. However, whether extended floral longevity increases seed production as pollinators decline depends on the limits to and costs of plasticity in longevity, both of which could be affected by drought stress. METHODS: To test whether drought stress affects the limits to and costs of plasticity in floral longevity in response to pollinator decline, we exposed Lobelia siphilitica to droughted and well-watered treatments and measured floral longevity and the number of seeds produced by flowers pollinated on day 1 vs. day 5 of the female phase. If floral longevity is shorter in the droughted treatment, then drought stress could limit the expression of extended longevity. If delaying pollination until day 5 reduces seed production more in the droughted treatment, then drought stress could increase the cost of extended longevity. RESULTS: The droughted treatment reduced floral longevity by ~18% but did not affect the number of seeds produced by flowers pollinated on day 1 vs. day 5. Instead, delaying pollination until day 5 reduced the number of seeds by ~24% in both the droughted and well-watered treatments. CONCLUSIONS: Drought stress does not affect the cost of plasticity in floral longevity but could limit the expression of extended longevity. Consequently, whether extended floral longevity could increase seed production as pollinators decline may depend on human-induced changes in precipitation.

Source: American Journal of Botany

DOI: 10.1002/ajb2.70163

Authors: Caelen McCabe, Christina M. Caruso

Institution: University of Guelph

Language: English

Topic: Plant and animal studies

Subfield: Ecology, Evolution, Behavior and Systematics

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $2,660