Abstract Detail

Reproductive Processes

Diller, Carolina [1], Egan, Paul E. [1], Stenberg, Johan A. [1].

To self or to clone? Mechanisms driving reproductive assurance strategies across wild strawberry genotypes.

Background and Aims Under the increasingly frequent pollinator limited environments, we have an appreciable understanding of the role of autonomous selfing and cloning as modes of reproductive assurance in plants that can either self or clone. Less clear is the relative role of selfing and cloning in plants that can do both. Here, we evaluate the allocation to autonomous selfing and cloning under a pollination free environment and test if this is determined by resource competition or by factors limiting autonomous selfing, such as poor anther-stigma contact and early inbreeding depression. The capacity to self-fertilize, in turn, can be influenced by pollinator reliability. We thus also tested whether the relative expression of selfing and cloning follows a latitudinal gradient, following the assumption of reduced pollinator reliability at more northern latitudes.
Methods We established an outdoor common garden experiment with 106 wild strawberry genotypes (Fragaria vesca) from across Europe and excluded them from pollinators. On each genotype, we recorded several phenotypic traits and performed hand pollination treatments.
Key Results We found a tradeoff between runner production and the size and achene set of autonomous fruits. In addition, the capacity to autonomously self-fertilize was determined by traits such as the lateral proximity of the anthers to the pistils in the flowers (i.e. lateral herkogamy) and by early inbreeding depression. However, all possible reproductive assurance strategies: ‘mainly clone’, ‘self and clone’, and ‘mainly self’ were uniformly distributed across Europe.
Conclusions Both resource competition and factors limiting the capacity to autonomously self-fertilize impact the relative expression of the reproductive assurance modes. The random distribution of reproductive assurance strategies across latitude and longitude suggests that finer scaled geographical variables determine the pollinator reliability for F. vesca. This work provides an initial framework towards greater understanding of the evolutionary interplay of selfing and cloning as joint modes of reproductive assurance.

Related Links:

1 - Swedish University of Agricultural Sciences, P.O. Box 190, SE-23422, Lomma, 23422, Sweden

autonomous selfing
selfing syndrome
pollen limitation
Reproductive assurance
inflorescence exsertion
Resource allocation
wild strawberry

Presentation Type: Oral Paper
Number: RP1005
Abstract ID:448
Candidate for Awards:None

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