Diagnosis and distribution of Citrus tristeza virus in northern Veracruz, Mexico

Abstract

Objective: of the research was to know the incidence of CTV to try to associate it with the yellowing and death of citrus trees. Design/ Methodology/ Approach: the presence of the virus was diagnosed in seven citrus-producing municipalities in northern Veracruz. A total of 804 samples from citrus trees were collected in 90 locations belonging to the municipalities of Álamo, Castillo de Teayo, Cazones, Chicontepec, Ixhuatlán, Papantla and Tihuatlán. Results: out of all the samples, 380 were positive for CTV; 68% corresponded to attenuated variants and 40% to severe variants. The following symptoms were observed in all the municipalities: death of branches (68%), yellowing of shoots (41%), trees with small leaves (38%), and debarking of the trunk (32%); the incidence of small fruits was 31%, and finally, generalized yellowing (19%). Limitations/ Implications of the study: to manage the disease there are various alternatives, the most frequent is the use of tolerant rootstocks, however, with the existence of severe variants there may be tree deaths even with tolerant rootstocks, so it is necessary to search for and implement other far-reaching options. Findings/ Conclusions: the results show that even with the regulations for the production and mobilization of plants, the virus is widely distributed in the seven municipalities of northern Veracruz.