Floral longevity and autonomous selfing in Collinsia

Under drought stress, cross-pollination early in floral lifespan of Collinsia reduces floral longevity, but excess soil moisture does not extend longevity.
Floral longevity and autonomous selfing in Collinsia
Floral longevity and autonomous selfing in Collinsia

Collinsia heterophylla, a protandrous, preferentially cross-pollinating hermaphrodite, undergoes delayed selfing facilitated by floral senescence. Jorgensen and Arathi find that under drought stress, cross-pollination early in the floral lifespan reduces floral longevity, but excess soil moisture does not extend longevity. Pollen receipt, a reliable cue for fecundity, accelerates flower drop, but similarly reduced longevity in unmanipulated flowers under water-stress generates a potential for exacerbating sexual conflict in this species. Reduction in longevity under drought suggests a strong environmental effect that could perhaps alter the preferred breeding mode; however, higher outcrossed seed production over that by autonomous selfing implies that inbreeding depression may limit the benefits of selfing.