Cucurbit downy mildew (Pseudoperonospora cubensis)-biology, ecology, epidemiology, host-pathogen interaction and control

Cucurbit downy mildew, caused by the oomycete Pseudoperonospora cubensis, is a devastating, worldwide-distributed disease of cucurbit crops in the open field and under cover. This review provides recent data on the taxonomy, biology, ecology, host range, geographic distribution and epidemiology of P. cubensis. Special attention is given to host-pathogen interactions between P. cubensis and its economically-important cucurbit hosts (Cucumis sativus, C. melo, Cucurbita pepo, C. maxima, and Citrullus lanatus); pathogenic variability in P. cubensis at the species, genus, and population levels; and, differentiation of pathotypes and races. Genetics and variability of host resistance and cellular and molecular aspects of such resistance are considered. A focus is given to methods of crop protection, including prevention and agrotechnical aspects, breeding for resistance-classical and transgenic approaches, chemical control and fungicide resistance. Novel technologies in biological and integrated control are also discussed. This review also summarizes the most important topics for future research and international collaboration.