Diffusion of Paraquat Resistant Gene by Pollen Flow in the Natural and Designed Populations of Erigeron philadelphicus L.

Abstract

The diffusion of genes by pollens was analyzed in a natural population of Erigeron philadelphicus that had paraquat resistant genotypes and in an experimental population designed with 4 resistant plants as center, 36 susceptible plants as surroundings and two susceptible satellite blocks. Pollen flow occurs generally in leptokurtic fashion, while our observation indicated a bimodal distribution of diffusion within a 1.2m distance by bees and syrphids in the natural population. Experimental results indicated that although predominant pollinators fly in a near-neighbor fashion, the pattern of gene diffusion over 3m by pollen may be affected by patchy distribution of individual plants in this outbreeding species.