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Shade tree hosts affected by BLS
Table 1. Shade tree hosts affected by BLS.
| Scientific name | Common name |
| Acer sp. | |
| A. rubrum | Red maple |
| A. negundo | Boxelder |
| A. saccharum | Sugar maple |
| Cornus florida | Flowering dogwood |
| Celtis occidentalis | Hackberry |
| Liquidambar stryraciflua | Sweet gum |
| Morus alba | White mulberry |
| Platanus sp. | |
| P. occidentalis | American sycamore |
| P. x acerifolia | London plane |
| Quercus sp. | |
| Q. velutina | Black oak |
| Q. incana | Bluejack oak |
| Q. macrocarpa | Bur oak |
| Q. prinus | Chestnut oak |
| Q. laurifolia | Laurel oak |
| Q. virginiana | Live oak |
| Q. rubra | Northern red oak |
| Q. palustris | Pin oak |
| Q. stellata | Post oak |
| Q. coccinea | Scarlet oak |
| Q. imbricaria | Shingle oak |
| Q. shumardii | Shumard oak |
| Q. falcata | Southern red oak |
| Q. bicolor | Swamp white oak |
| Q. laevis | Turkey oak |
| Q. nigra | Water oak |
| Q. alba | White oak |
| Q. phellos | Willow oak |
| Ulmus americana | American elm |
Table 2. Some of the economically important diseases caused by Xylella fastidiosa characterized by the primary symptom expressed.
| Leaf scorch | Almond leaf scorch (Prunus amygdalus) |
| Bacterial leaf scorch of shade trees | |
| Coffee leaf scorch (Coffea arabica) | |
| Oleander leaf scorch (Nerium oleander) | |
| Pear leaf scorch (Pyrus pyrifolia) | |
| Pecan leaf scorch (Carya illinoinensis) | |
| Pierce’s disease of grapevine (Vitis spp.) | |
| Plum leaf scald (Prunus domestica, P. salicina) | |
| Stunt | Alfalfa dwarf (Medicago sativa) |
| Citrus variegated chlorosis (Citrus spp.) | |
| Phony peach disease (Prunus persica) | |
| Periwinkle wilt (Catharanthus roseus) |
Table 3. Some alternative hosts of Xylella fastidiosa.1
| Scientific name | Common name |
| Aesculus x hybrid | Buckeye |
| Ampelopsis arborea | Peppervine |
| Ampelopsis brevipedunculata | Porcelain berry |
| Artemisia spp. | Mugwort |
| Baccharis halimifolia | Eastern baccharis |
| Callicarpa americana | American beautyberry |
| Celastrus orbiculata | Oriental bittersweet |
| Cynodon dactylon | Bermuda grass |
| Fagus crenata | Japanese beech bonsai |
| Fragaria californica | Wild strawberry |
| Hedera helix | English ivy |
| Montia linearis | Miner’s lettuce |
| Parthenocissus quinquefolia | Virginia creeper |
| Parthenocissus tricuspidata | Boston ivy |
| Paspalum dilatatum | Dallis grass |
| Rhus sp. | Sumac |
| Rubus procerus | Blackberry |
| Sambucus canadensis | American elder |
| Solidago fistulosa | Goldenrod |
| Sorghum halapense | Johnson grass |
| Trifolium repens var. latum | Landino clover |
| Vitis sp. | Wild grape |
For a more complete list of alternative hosts, refer to the Xylella fastidiosa web site: http://www.cnr.berkeley.edu/xylella/index.html.
Table 4. Methods used to detect Xylella fastidiosa1.
| Technique | Sensitivity2 (number of bacterial cells) |
Cost and labor |
| Culture from xylem fluid on selective media | 1000 | Low |
| ELISA3 | 100,000 | Med |
| PCR | 100 | High |
| IC-PCR4 | <100 | High |
1Adapted from R. Jordan. 2002. In: Bacterial Leaf Scorch in Amenity trees: A Wide-Spread Problem of Economic Significance to the Urban Forest. Lashomb, J., A. Iskra, A.B. Gould, and G. Hamilton, eds. Vol. NA-TP-01-03: USFS
2Lowest approximate number of bacterial cells that the assay can detect.
3Enzyme-linked immunosorbent assay
4Immunocapture-PCR
Table 5. Some known leafhopper vectors of Xylella fastidiosa.
| Host | Insect vector |
| Citrus (Brazil) | Acrogonia terminalis Dilobopterus costalimai Oncometopia fascialis Oncometopia nigricans |
| Grape | Carneocephala fulgida Draeculacephala minerva Graphocephala atropunctata Homalodisca coagulata Oncometopia nigricans |
| Oleander | Homalodisca coagulata Homalodisca lacerta |
| Peach, plum | Graphocephala versuta Homalodisca coagulata Homalodisca insolita Oncometopia orbona |
Table 6. Discovery of the identity of Xylella fastidiosa.
| 1890s | California vine disease (now known as Pierce’s disease) and phony peach disease observed and studied in different parts of the United States; As Newton B. Pierce states, a "minute microorganism" may be involved. |
| 1936 to 1959 |
Root graft, budding, and/or insect transmission of Pierce’s disease, alfalfa dwarf, and elm scorch; causal agent considered to be a virus. |
| 1971 | Tetracycline antibiotic suppresses development of Pierce’s disease; causal agent now considered to be a mycoplasma-like organism (MLO). |
| 1973 | Electron microscopy reveals a "Rickettsia-like bacterium" in xylem tissues associated with Pierce’s disease and phony peach disease; elm leaf scorch still considered to be caused by a virus. |
| 1978 | Selective media were defined and a bacterium isolated from infected grapevine xylem tissues. |
| 1980 | A xylem-limited bacterium was associated with leaf scorch of elm. |
| 1987 | Xylella fastidiosa described as a new bacterial species. |
| 2004 | New subspecies for Xylella fastidiosa described based on pathogenicity, phylogenetic characteristics, and DNA relatedness. |