Progeny Trials in an Introgressive Hybrid Population of Anigozanthos Labill. (Haemodoraceae)

Abstract

The floral morphology and pollen fertility of progeny from open-pollinated plants in a hybrid population of A. manglesii and A. humilis were measured to investigate patterns of gene exchange occurring between hybrid and parental individuals. Introgression occurs where the two species and F₁ hybrids grow in close proximity in the population but the possibility of more backcrossing to A. manglesii than to A. humilis remains an open question on present evidence. The morphological effects of hybridization became cryptic in some cases within one and in most cases within two generations of backcrossing. The possible evolutionary significance of natural hybridization between A. manglesii and A. humilis is discussed in the light of these results.