Xyphon fulgida (Nottingham 1932a: 101)Membracoidea : Cicadellidae
Red headed Sharpshooter
|Diseases Transmitted||Pathogen Type|
|Crops Affected by Xyphon fulgida (Nottingham 1932a: 101)|
This species is a vector of Pierce’s disease virus of grape in California. The first indication that this species transmitted a virus was reported by Hewitt et al. in 1942 (360) in their early studies of this disease. Later on in 1942 these workers (361) confirmed transmission and obtained positive identification of the species.
Tests on natural infectivity were undertaken on alfalfa for transmission of alfalfa dwarf virus (Hewitt et al 1946) . None of the leafhoppers carried the virus, but when they were given 24 hours’ feeding on diseased alfalfa they transmitted the virus to 19 percent of the alfalfa plants used in the test. Similar results were obtained with Pierce’s disease virus of grape. However, further studies showed that only 4 percent of the leafhoppers were naturally infected.
Intertransmission tests using alfalfa and grape as sources of inoculum and healthy test plants resulted in 59 and 42 percent transmission, respectively, from diseased grape to healthy grape and alfalfa and 71 and 61 percent transmission, respectively, from diseased alfalfa to healthy grape and alfalfa. These studies offered the first proof that alfalfa dwarf and Pierce’s disease of grape were caused by the same virus.
Houston et al. in 1947 (378) found this species to be a xylem feeder, which led Severin in 1949 (706) to study the latent period of the virus in the vector. His results showed a minimum latent period of 2 hours and a maximum of 7 hours.
Studies on the host range of the virus by Freitag in 1951 (282) showed that 75 species of plants in 23 families were experimentally infected with fulgida and 2 other species of leafhopper vectors. Thirty-six species in 23 families of plants were naturally infective including bermudagrass, the principal host of fulgida. Additional studies on natural infectivity of vectors were conducted by Freitag and Frazier in 1954 (286), who found naturally infective nymphs and adults from nearly every type of habitat, including vineyards, roadsides, ditches, irrigated pastures, and natural breeding areas. The vector carried the virus during all seasons of the year and produced 14.6-percent infection compared to an earlier report of 4 percent by Houston et al. in 1947 (378).
This species is considered one of the most important vectors in the natural spread of Pierce’s disease virus in California.
Medium size, slender species. male 4.10—4.50 mm., female 5.10—5.70 mm.
General color green with pronounced venation on elytra. Crown light reddish green; pronotum green; elytra green with distinct ivory or yellow veins, reticulated at apex.
Pygofer in lateral aspect twice as long as wide, caudodorsal margin produced posteriorly to broadly rounded lobe, dorsal margin slightly concave; aedeagus in lateral aspect simple, attenuated distally, small tooth basally on dorsal margin, shaft platelike, narrow in ventral aspect; gonopore terminal; aedeagal processes symmetrical; style in dorsal aspect simple, sharply attenuated apically; female seventh sternum in ventral aspect with caudal margin rounded.
to which it is similar,
can be separated by the aedeagus with. an elongate oval-shaped shaft in ventral aspect.
|Nielson, M. W. 1968b. The leafhopper vectors of phytopathogenic viruses (Homoptera, Cicadellidae). Taxonomy, biology and virus transmission. United States Department of Agriculture Technical Bulletin . 1382 386 pp.|