Plant Protect. Sci., 2002, 38(10):232-234 | DOI: 10.17221/10361-PPS

Developing Verticillium resistant rootstock for Norway mapleOriginal Paper

J.A. Hiemstra

Plant Research International, 6700 AA Wageningen, The Netherlands

Verticillium wilt causes serious losses in the cultivation of shade trees, especially Norway maple (Acer platanoides L.).In 1993 research was started aiming at the development of Verticillium resistant rootstocks for Norway maple. Efficientmethods to select and screen for resistance in maple were developed, leading to several large-scale selection experimentscarried out in the period 1994-1996. This resulted in a first selection of about 300 plants out of a total of nearly 20 000 seedlingplants. An attempt was made to propagate these plants vegetatively in order to develop small clones for resistancetesting. During this stage of the research many plants were lost because of failure to propagate. After a second screeningfor resistance 35 plants were selected for further examination. Vegetative propagation was continued and from 2000 onthe performance of about 15 clones could be tested on naturally infested fields as well as after inoculation. The resultsof the field test show a clear selection response with disease incidence in plants of the selected clones being 50% lessthan in the seedlings and the randomly chosen clones. Within the group of selected clones there was a substantial variationbetween the clones with some clones having no disease at all whereas in other clones some plants showed serioussymptoms. Results of the field tests will be presented and the possibilities for solving the Verticillium wilt problem inmaple by means of using clonal root-stocks that are resistant to Verticillium wilt will be discussed.

Keywords: Verticillium dahliae; Acer platanoides; resistance; selection; rootstock; shade trees

Published: June 30, 2002  Show citation