Grafting and Fungi in the Nursery
摘要
Grapevines have been grafted since the Phylloxera blight of the late nineteenth century. The root form of the louse responsible for Phylloxera, Daktulosphaira vitifoliae, attacks the roots of the European vine (Vitis vinifera), causing its rapid decline. The accidental importation of this insect from the northern USA led to a fundamental change in grapevine propagation practices worldwide. The grafting technique introduced in the wake of the phylloxera outbreak consists in joining the graft of a European grapevine (Vitis vinifera) which is susceptible to the root form but resistant to the leaf form of the insect pest onto a rootstock of American origin (Vitis spp), resistant to the root form but susceptible to the leaf form of the pest. The choice of rootstock is based on soil type, in particular soil limestone content, drought resistance, and conferred graft vigour. Grapevine plants are produced by vine nurserymen who graft and market rooted grafts after stratification and 1 year’s growth in a nursery. Each production stage must be carried out under irreproachable hygiene conditions, including cane disinfection stages to ensure propagation material limiting the presence of fungal pathogens that could alter the rooted-graft production process.