Non-Random Fruit Retention in Yucca filamentosa: Consequences for an Obligate Mutualism

摘要: Post-pollination selective flower abortion can provide plants with a mechanism to exact some control over which fruits are matured. In Yucca filamentosa, seed quality and quantity limited by the oviposition pollination behaviors of its obligate mutualist, yucca moth Tegeticula yuccasella. The plant produces many more flowers than ever become mature fruit selectively retains those receiving few eggs large pollen loads. This study addresses additional factors that affect patterns floral abortion. We document intrinsic differences in probability Y. filamentosa based on position, herbivory beetle coexists moths. then ask how they plant-moth interaction. Pollination experiments showed retention was positively correlated late flowering within an inflorescence, distal position side branches, number branch. all flowers, early only, or only did not result different overall set, suggesting resources for maturation be allocated response fluctuations pollinator availability. Competition among plays important role determining fruits. Flowers attacked larvae adults nitidulid Carpophilus melanopterus invariably abscised, regardless status. Beetles were estimated responsible 37% abscission. Beetle damage precedes T. yuccasella visitation any aborted do survive. For this reason, moths should avoid beetle-infested flowers. However, there no evidence avoided Intrinsic triggered beetles add previously documented egg- pollination-driven moth. Together, these create complex landscape probabilities may influence