Evaluate strategies for management or prevention of fire blight infection of apple rootstocks
The loss of trees due to rootstock blight is becoming less of a headline with the increased awareness growers have in managing blossom blight in new plantings for susceptible varieties and susceptible rootstocks. A second change is that the industry is switching from M9 to B9 rootstocks. Although B9 is susceptible to fire blight infection, it survives under field conditions with high disease pressure when used as the rootstock under the scion variety. Nurseries are reporting the sales of more B9 vs. M9. However, the 2004 bloom period presented a research opportunity to observe the effects of copper applications (+ or -) with pruning out infections (+ or -) in a Gala orchard that was showing symptoms of shoot infection and some blossom blight around June 8. The grower was responding to market demands of bigger Gala by increasing nitrogen applications and not using Apogee as a preventative shoot blight strategy due to the limitation on the use of Apogee by the UK market.
New York State IPM Program
Agricultural IPM; Apples; Fruits; Tree Fruit