Re-emergence of grey leaf spot caused by Stemphylium botryosum and its implications for Western Australian lupins

摘要

Stemphylium grey leaf spot was a damaging disease of Lupinus angustifolius crops in Western Australia during the 1970s. It has rarely been reported since the release of resistant cultivars more than 30 years ago. Severe grey leaf spot symptoms, caused by Stemphylium botryosum, were observed recently in experimental lupin plots at South Perth, Western Australia. More than a third of Lupinus angustifolius advanced breeding lines screened were susceptible, although known resistant cultivars remain effective. These investigations suggest that widespread deployment of susceptible cultivars could result in re-emergence of this disease in Western Australian lupin crops.