Spatial autocorrelation analysis of allozyme variants within local sites of wild radish population

The spatial distribution of allozyme alleles was studied at two local sites of a natural population of wild radish, an inland site in 1988 and 1989 and a beach site in 1988. Randomness of the spatial distribution of genotypes was tested at four isozyme loci in adult plants and fertilizing pollen by spatial autocorrelation statistics. At the inland site, significant aggregation of an identical allele was observed at two loci each in 1988 and 1989 for adult plants. At these loci, aggregation of an allele was observed also for pollen cloud. The aggregation, however, was not stable; the loci which showed significant aggregation differed in two successive seasons. These observations can be interpreted either by limited but moderate pollen dispersal or the great variation in fertility among the adult plants. The latter accidentally causes aggregation of identical alleles. At the beach site, the seed bank was disturbed by tractors for fishing work, and this led to a random distribution of alleles.