Short distance pollen dispersal for an outcrossed, wind-pollinated southern beech (Nothofagus nervosa (Phil.) Dim. et Mil.

MARCHELLI, P; SMOUSE, PE; GALLO, L A

TREE GENETICS & GENOMES

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2012 vol. 8 p. 1123 - 1134

1614-2942

The mating system (outcrossing, selfing, and biparental inbreeding) and the extent of pollen flow are two of the most important genetic features that determine the genetic structure of plant populations, and both are crucial for the design of conservation strategies. The objectives here were to estimate mating system parameters and to fit the pollen dispersal kernel for the southern beech, Nothofagus nervosa. We sampled 25 mothers and 372 progeny from two stands in the Tromen Lake region of Argentina. We registered spatial positions of the maternal trees, and genotyped mothers and offspring for five simple sequence repeat markers. We estimated single-locus (ts 00.95) and multilocus (tm 00.99) outcrossing rates and biparental inbreeding (tm-ts00.04). The species is strongly outcrossing, but correlated paternity within maternal sibships (rp00.10) indicates that each maternal parent is sampling a different and restricted array of pollen donors. We used two protocols (TWOGENER and KINDIST) to fit an exponential power dispersal kernel to the structure of pollen clouds sampled by different mothers. The estimated effective number of pollen donors contributing to a single mother was Nep09.9. The TWOGENER and KINDIST analyses yielded slightly different estimates, but both indicated short average distances for pollen dispersal (