Macropsis trimaculata (Fitch)Membracoidea : Cicadellidae
|Diseases Transmitted||Pathogen Type|
|Crops Affected by Macropsis trimaculata (Fitch)|
This species is a vector of peach yellows virus and little peach virus in the Eastern United States and Canada. Kunkel (428) first demonstrated transmission of peach yellows virus in 1933. Both nymphs and adults were confined from 2 to 21 days to diseased peach seedlings, then transferred to healthy peach seedlings. Of 74 exposed trees, 7 were infected with the Virus. Confirmation of Kunkel’s work was reported by Hartzell between 1936 and 1937 (336, 337), Manns and Manns in 1935 (471), and Manns in 1938 (468).
In Hartzell’s 1936 work (336), only 14 of 86 trees exposed to viruliferous leafhoppers became diseased. He reported that the incubation period in the nymphs did not exceed 22 days and in the adults, 32 days. Further studies by Hartzell in 1937 (337) revealed that the maximum incubation period ranged between 10 and 26 days and averaged 16 days. The minimum period varied from 7 to 8 days.
In 1935, Manns and Manns (471) transmitted the virus from infected plums to peach, resulting in 10- to 15-percent infection in the test trees. When numbers of viruliferous insects were increased, Manns in 1938 (468) was unable to produce more than 12-percent infection. A detailed review of the history and transmission of peach yellows was presented by Manns in 1942 (469).
Transmission of the little peach virus was first reported in 1935 by Manns and Manns (471). Three of ten peach trees were infected with this virus during the initial studies. Further studies were reported by Manns in 1938 and 1942 (468, 469) and Manns and Davies in 1936 (470).
This species is an important vector in the natural spread of these viruses. The vector, however, is not considered efficient as evidenced by the transmission tests.
Small, robust species. male 4.00—4.30 mm., female 4.50—4.80 mm.
General color light brown to dark brown. Crown and pronotum light brown to dark brown, immaculate; elytra dark brown, translucent.
Pygofer in lateral aspect slightly longer than wide, caudoventral margin with distinct spine projecting dorsally, bulbus subapically on lateral margin; aedeagus in lateral aspect broad basally, somewhat narrowed apically, slightly curved, apex of shaft flairing laterally in dorsal aspect; gonopore terminal; style extremely long, narrow, curved laterally at apex; female seventh sternum in ventral aspect with lateral margins converging caudally to narrow truncate caudal margin.
This species, similar to
can be easily distinguished by the pygofer spine with a subapical lobe and the aedeagus, which is flanged apically.
|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.|