Citrus Tristeza Virus
Citrus tristeza virus (CTV), Closterovirus
Overview
One of the most economically important citrus diseases, transmitted by aphids (especially the brown citrus aphid). Has killed over 100 million citrus trees worldwide on susceptible rootstocks.
Symptoms
Quick decline and death on sour orange rootstock. Stem pitting on grapefruit and sweet orange. Seedling yellows. Inverse pitting of bark. Reduced fruit size and quality. Gradual decline.
Environmental Conditions
Variable
Prevention
Use tolerant rootstocks (not sour orange). Use certified virus-free budwood. Control brown citrus aphid. Cross-protection with mild strains. Regular testing programs.
Management
No cure. Remove trees on susceptible rootstocks. Replant on tolerant rootstocks (Swingle citrumelo, Carrizo citrange). Control aphid vectors. Cross-protection programs.