Downy mildew of rose
extruding from the stomata. In lettuce, the foot is infected first and this causes the plant to fall over. In cabbage the stem is also infected in severe epidemics [...] brown. On the underside of the leaf fluffy growth appears which is first white and later turns grey-brown. This is, in fact, the sporulation of the pathogens [...] temperature is to these 15 °C , the shorter the leaf wetness period that is required for germination. Inside the plant, the pathogens produce haustoria, small