Phony Peach Disease Damage
First observed in Georgia around 1890, apricots with phony peach disease (PPD) have a compact, flat canopy– the result of shortening of the internodes. Foliage tends to be a darker green than normal and infected trees usually flower and set fruit early and hold their leaves later in the fall than those uninfected. The result is smaller fruit combined with a considerable reduction in yields. Twigs on diseased apricots not only have shortened internodes but an increase in lateral branching. Overall, the tree appears dwarfed with compact growth. As the disease progresses, the wood becomes dry and brittle accompanied by dieback. Trees that develop symptoms of Xylella fastidiosa prior to bearing age never produce fruit. PPD is spread through root grafting and by leafhoppers. Apricots afflicted with phony peach disease can be found from North Carolina into Texas. The milder temperatures of these regions foster the insect vector, the sharpshooter leafhopper. Similar forms of the bacterium cause plum leaf scald, Pierce’s disease of grapes, citrus variegated chlorosis, and leaf scorch in trees (almond, olive, coffee, elm, oak, oleander, and sycamore).
Apricot Xylella Treatment
There is currently no cure for PPD. Options are limited to the spread of the disease. To this end, any diseased trees should be removed. These can be easily identified by the reduced shoot growth in late summer. Remove the trees prior to pruning which can make the disease difficult to identify. Also, as to pruning, avoid pruning in the summer which encourages growth that leafhoppers are attracted to. Keep the areas surrounding the apricot trees weed free to reduce habitat for leafhoppers. Remove any plum trees, wild or otherwise, near the apricot trees.
