tristeza caused by citrus tristeza virus (ctv), is the most important viral disease of citrus worldwide. serious damages of the disease have been reported from many citrus growing areas of the world. ctv particles are restricted to phloem and are transmitted by aphids in a semipersistent manner. ctv was introduced from japan to mahdasht orchards in mazadaran province in 1969. its natural spread...

ABSTRACT The assessment of citrus tristeza virus incidence by sampling involves laboratory testing by enzyme-linked immunosorbent assay of leaf material collected in the field. Using field data and computer simulation, methods of field data collection were compared. One method was similar to that used by the Central California Tristeza Eradication Agency, in which 4 to 6% of the trees in a plan...

Tristeza, caused by Citrus tristeza virus (CTV), has long been present in Florida but outbreaks of decline on sour orange rootstock were occasional events until the late 1970s. Sour orange rootstock was valued for the high quality of fruit produced and was widely used because of its tolerance of citrus blight, a disease of unknown etiology. Research was directed towards the selection and screen...

The brown citrus aphid, Toxoptera citricida (Kirkaldy), is considered the primary vector of citrus tristeza virus, a severe pathogen which causes losses to citrus industries worldwide. The alate (winged) form of this aphid can readily fly long distances with the wind, thus spreading citrus tristeza virus in citrus growing regions. To better understand the biology of the brown citrus aphid and t...

Citrus Tristeza disease, caused by CTV (Citrus tristeza virus), committs citrus plantations around the world and specifically attacks phloem tissues of the plant. The virus exists as a mixture of more or less severe variants, which may or may not cause symptoms of Tristeza. The objective of this study was to analyze the changes caused by CTV in the proteome of stems of sweet orange, as well as ...

The Sudanese citrus industry is mainly based on oldline cultivars of grapefruit, sweet orange and willow leaf mandarin, grafted almost exclusively on sour orange. Infection with graft-transmissible agents, viroids in particular, may have deleterious effects on the productivity of these citrus species and, more importantly, limits the choice of rootstocks should sour orange be replaced by altern...

A formal citrus insect pest survey was conducted in two citrus growing districts of Kenya, Bungoma and Machakos, to determine important insect pests of citrus and evaluate the pest control practices used by small-scale farmers. Observations were made on the insect pests and their damage, methods of pest control practiced, pesticide products used, sources of farming knowledge and how decisions t...

Citrus trees harbor a large number of viral and bacterial pathogens. Citrus yellow vein clearing virus (CYVCV), Indian citrus ringspot virus (ICRSV), Citrus yellow mosaic virus (CYMV), Citrus tristeza virus (CTV) and a bacterium, Candidatus Liberibacter asiaticus (CLa) associated with huanglongbing (HLB) disease, the most prevalent pathogens in citrus orchards of different regions in India and ...