| incidence and epidemiology of citrus tristeza virus in the valencian community of spain. | the first outbreak of citrus tristeza disease in spain caused by citrus tristeza virus (ctv) was recorded in 1957 in the valencian community (vc). in total c. 40 million trees, mainly of sweet orange and mandarin grafted on sour orange rootstocks, declined due to ctv. large-scale surveys in different municipalities of the vc indicated that the disease spread very fast. incidence increased from 11% in 1989 to 53% in 1998. toxoptera aurantii and aphis spiraecola (inefficient aphid vectors of ctv) ... | 2000 | 11137164 |