Direct Producer

direct producer, term used for a group of vines, also known as french hybrids, bred from the late 19th century onwards in an effort to combine the pest and disease resistance of american vine species with the desirable fruit characters of the European vinifera species. They are called direct producers, and sometimes hybrid direct producers, or HDPs, because, unlike V. vinifera vine varieties, they do not need grafting on to phylloxera-tolerant rootstocks. They are not all sufficiently phylloxera-tolerant, however, and added soil stresses such as drought or weeds can see them weakened by phylloxera.