Variation in important pasture grasses. II. Cytogenetic and reproductive variation.

Abstract

The chromosome numbers and reproductive variation of seven important pasture grasses from South Africa are compared. This comparison indicates that all these species form polyploid complexes, all reproduce both sexually and either apomictically or vegetatively, and some form of hybridization or cross-fertilization occurs in each species. The ecological success of these species can, therefore, be attributed to the fact that they combine the advantages of polyploidy and apoximis and, at the same time, bypass the disadvantages with their hybridization potential.

Keywords: apomixis; cenchrus cilliaris; chromosome number; chromosome numbers; cynodon dactylon; digitaria eriantha; eragrostis curvula; grass; grasses; heteropogon contortus; hybridization; pasture; pasture grasses; polyploidy; setaria sphacelata; south africa; themeda triandra; variation