WATSON, MAXINE A.*, CYNTHIA S. JONES, AND YING LU. Department of Biology, Indiana University, Bloomington, IN 47405. - Variation in the expression of developmental and phenological traits in mayapple, Podophyllum pelatum L. (Berberidaceae).
Plants' programs of development can be considered evolved traits. If
this is correct, then we should be able to detect variation among
clones in developmental traits and demonstrate that this variation
leads to fitness differences. Here we report variation in three
developmental traits: timing of shoot emergence and senescence and the
timing of shoot type determination. We demonstrate significant
variation among colonies for all three traits. A reciprocal
transplant experiment in the field goes on to demonstrate that the
timing of emergence and senescence has both a genetic and
environmental component. Variation in emergence and senescence date
should effect clonal resource dynamics while variation in the timing
of shoot type determination should effect how both short and long term
environmental variation influences the demographic trajectory and,
hence, fitness of different clones. Further reciprocal transplant
experiments are needed to demonstrate genetic variation in the timing
of shoot type determination.
Key words: Berberidaceae, developmental programs, phenological traits, Podophyllum pelatum