Bacterial leaf scorch
Bacterial disease of plants
From Wikipedia, the free encyclopedia
Bacterial leaf scorch (BLS), or bacterial leaf spot, is a disease state affecting many crops, caused mainly by the xylem-plugging bacterium Xylella fastidiosa.[1] It can be mistaken for ordinary leaf scorch caused by cultural practices such as over-fertilization.[1]
_stricken_with_bacterial_leaf_scorch_during_leaf-out_near_the_house_at_988_Terrace_Boulevard_in_Ewing,_New_Jersey.JPG)
| Bacterial leaf scorch | |
|---|---|
Large pin oak (Quercus palustris) stricken with bacterial leaf scorch during leaf-out | |
| Common names | BLS |
| Causal agents | Xylella fastidiosa |
| Hosts | trees and crops |
| Vectors | leafhoppers |
Hosts
BLS can be found on a wide variety of hosts, ranging from ornamental trees (elm, maple, oak) and shrubs, to crop species including blueberry and almond.[2]
- Xylella fastidiosa is known to cause BLS in a very wide range of plants. Each of its subspecies has have a different host range.[2]
- The multiplex subspecies causes BLS of pecans.
- Bacterial spot of peppers and tomatoes is caused by the bacteria Xanthomonas campestris pv. vesicatoria, which has since been divided into four pathovars in three species.[3]
- Bacterial spot of peaches is caused by the bacteria Xanthomonas arboricola pv. pruni. It also infects almonds.[4] Spots may form on the leaves and they can be mistaken for peach scab, which is caused by a fungus.
Symptoms
An irregular browning leaf margin which may or may not be bordered by a pale halo.[5]
Symptoms re-occur every year, spreading throughout the tree crown, eventually killing the host plant.[5]
Vectors
Xylem-feeding leafhoppers can transmit the disease bacteria.[5] In general, any xylem-feeding insect can transmit the disease.[6]
Treatment
There are no known effective treatments for BLS, consequently, removal of affected plants is recommended.[5]
