GENGLER, KARLA M.* AND DANIEL J. CRAWFORD. Department of Plant Biology, Ohio State University, Columbus, OH 43210. - Allozyme diversity in central Peruvian species of Malesherbia (Malesherbiaceae).
Little is known about the Peruvian members of the Pacific coastal
endemic Malesherbia due to their rarity and the inaccessibility
of many species. Enzyme electrophoresis was employed to examine
allozyme diversities for one population of M. splendens and two
of M. tubulosa, both endemics of the department of Lima, one
population of M. weberbaueri var. weberbaueri, an
endemic of the Andean department Huancavélica, and the two Limeño
populations of M. scarlatiflora. These species are closely
related and probably recently derived in the family. Fifteen loci were
examined for all populations and an additional seven loci were
resolved for M. weberbaueri and M. splendens. Mean
number of alleles per locus (A), proportion polymorphic loci (P), and
expected heterozygosity (Hs) are low for M.
scarlatiflora (A = 1.36, P = 0.273, Ht = 0.083), which
is heavily collected for the herbal medicine trade, and for M.
splendens (A = 1.21, P = 0.214, Hs = 0.057) and M.
weberbaueri (A = 1.23, P = 0.154, Hs = 0.079), which
are both known from three or fewer populations. In M. tubulosa,
Ht and P are somewhat low in comparison to other endemics,
but the mean number of alleles is comparable (A = 1.82, P = 0.364,
Ht = 0.206). Malesherbia tubulosa seems to
experience little interpopulational gene flow (Nm = 0.294),
while gene flow between populations of M. scarlatiflora appears
to be much higher (Nm = 3.59). The low allozyme diversities
and restricted habitats of M. splendens and M.
weberbaueri suggest that they are the results of recent founder
events, while M. scarlatiflora may be in danger of local
extirpation due to overcollection. Greater allozyme diversities in
M. tubulosa could be attributable to its maintenance of larger
populations in a greater variety of habitats.
Key words: allozyme, diversity, Malesherbia, Malesherbiaceae, Pacific coastal desert, Peru