The cytology and reproduction of Paspalum yaguaronense (Henr)

Abstract

A high degree of sterility occurs in an introduction of Paspalum yaguaronense. Cytological and embryological studies have shown that the chromosome number is 2n = 20, and that the embryo sac develops normally. Sterility is due to an incompatibility system which prevents the growth of pollen tubes into the style. A self-fertile selection has been made in which fertilization occurs 4 hr after anthesis. Fertility probably arose by mutation of an incompatibility allele. The sterile plants will readily produce seed when pollinated by clones of the fertile plant. Because P. yaguaronense possesses a sexual method of reproduction and an incompatibility system, it could be useful in future breeding work within the genus Paspalum, which contains a number of apomictic species.