Breeding and use of summer-dormant grasses in Southern Australia, with special reference to phalaris
The adaptation of introduced perennial grasses in southern Australia expanded with the discovery of the Mediterranean grass phalaris (Phalaris aquatica L.) as a valuable pasture species, and the introduction of Mediterranean ecotypes of orchardgrass (Dactylis glomerata L.), and tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] displaying summer dormancy. In contrast, native grasses of agricultural importance appear to have little or no endogenous summer dormancy. A brief history of cultivar development from Mediterranean germplasm is presented. Recent developments include cultivars based on summer-dormant subsp. hispanica orchardgrass and the release of Mediterranean-type cultivars of tall fescue. Phalaris depends on a deep root system and summer dormancy for its summer survival. Cultivars based on more summer-dormant Moroccan ecotypes have been developed for drier environments. Work to improve phalaris for hotter, summer-dominant rainfall areas is being extended to enhance the range of perennials for the cropping zone. In addition to ecotype evaluation, breeders should employ recurrent selection in cultivars and populations such as those developed recently for low- to medium-rainfall areas in orchardgrass and tall fescue.