Peach Orchard Concerns

April 29, 2009

Over the past couple of weeks there have been several problems in peach orchards noticed. High chill varieties have been struggling as they did not receive sufficient chilling here in central Alabama. Over the last 5 days with warmer and dryer weather they are beginning to look better and getting excess fruit thinned should help even more.

Root Issues
Tree decline, due primarily to armillaria root rot, is beginning to show up all around the area. Damaged root systems were exposed to saturated soils from heavy rainfall this spring. Now with a load of small fruit and dryer weather, trees are going down.

Dr. Tom Beckman and I had a rootstock study here at our facility looking at possible resistant material for ARR. One of the rootstocks showed promise in other trials Dr. Beckman had run and performed okay here. While other material is being evealuated for the future, 'Sharpe' has been released.

'Sharpe' is a clonal plum hybrid rootstock that produces semi-dwarf peach trees (~ 60% standard size). Fruit size may also be slightly smaller. 'Sharpe' would be a good rootstock to trial on your farm in areas affected by Armillaria root rot.
To contact Dr. Beckman, tom.beckman@ars.usda.gov

Bacterial Leaf and Fruit Infections
Symptoms of Bacterial leaf spot began showing up recently. As of yesterday some of the very sensitive peach varieties are now showing severe infection. High level of leaves are shedding and young green fruit are showing visible signs of infection.

Not much can be done at this time for Bacterial spot. Stressed trees are often hardest hit so adding some addtional nitrogen may help trees keep ahead of the infection. See Southeastern Peach, Nectarine and Plum Pest management and Culture Guide for recommendations, link on Peach IPM home page.

'Carared' on 4/28/09 with leaf shed and fruit infections