Genetic improvement of subterranean clover (Trifolium subterraneum L.). 2. Breeding for disease and pest resistance

摘要: Subterranean clover (Trifolium subterraneum L.) is the most widely sown pasture legume in southern Australia and resistance to important diseases pests has been a major plant-breeding objective. Kabatiella caulivora, cause of scorch, foliar fungal pathogen, several cultivars have developed with both known races. Screening advanced breeding lines conducted prevent release high susceptibility other disease pathogens, including rust (Uromyces trifolii-repentis), powdery mildew (Oidium sp.), cercospora (Cercospora zebrina) common leaf spot (Pseudopeziza trifolii). Several oomycete species root rots subterranean clover, Phytophthora clandestina, Pythium irregulare, Aphanomyces trifolii, Fusarium avenaceum Rhizoctonia solani. Most efforts devoted P. but existence different races confounded selection. The economically virus pastures are mottle Bean yellow mosaic virus, while stunt red (local synonym for Soybean dwarf virus), Cucumber Alfalfa Clover vein Beet western yellows roll also losses. Genotypic differences found these fungal, viral highlighting potential develop improved resistance. redlegged earth mite (RLEM) (Halotydeus destructor), blue oat (Penthaleus major), blue-green aphid (Acyrthosiphon kondoi) lucerne flea (Sminthurus viridis). New bred increased RLEM cotyledon resistance, limited selection pests. pest largely ceased, recent molecular biology advances provide new platform development future multiple resistances However, this can only be realised if skills plant pathology, entomology, pre-breeding maintained adequately resourced. In particular, supporting phenotypic studies understanding their significance critical enable technology investments achieve practical outcomes deliver sufficient pathogen ensure productive across Australia.