Screening field pea germplasm for resistance to downy mildew (Peronospora viciae) and powdery mildew (Erysiphe pisi

摘要

Downy mildew (caused by Peronospora viciae) and powdery mildew (caused by Erysiphe pisi) cause significant yield losses in field pea crops of southern Australia. The Australian Coordinated Pea Improvement Program ( ACPIP) aims to select lines that are resistant to both of these pathogens. A method was developed to allow screening of early generation material for resistance against both diseases, through consecutive testing on single plants. The apical buds of plants were inoculated with conidial suspensions of P. viciae and the same plants were infected with E. pisi via airborne spores in the greenhouse. Of 88 lines tested, 25 had useful downy mildew resistance, 19 lines were resistant to powdery mildew and 14 lines displayed resistance to both pathogens. The results of the controlled environment and greenhouse trials were highly correlated with results of field screening; for downy mildew r = 0.88 (P < 0.001) and for powdery mildew r = 0.72 (P < 0.001).