http://www.cubanews.ain.cu/2007/1102estrategiacitricos.htm

Cuba Develops Strategy to Fight Destructive Citrus Virus

Havana, Nov 2 (acn) As a result of Cuban scientists' studies of the most destructive virus threatening citrus production, that is the Tristeza virus, epidemics caused by its most efficient vector have been prevented.

The internationally-recognized research was carried out by a multidisciplinary team headed by Drs.Lochy Batista Le Riverend, Ines Peña and Karelia Velasquez, with the Tropical Fruit Growing Research Institute, in collaboration with Francisco F. Laranjeira, with Brazil's Agricultural and Livestock Research Enterprise.

The Cuban scientists' study is the only one of its kind in the country and one of the first ones completed in the world, using modern statistical techniques and the analysis of the focal structure, which are methods rarely used on plants.

Dr. Lochy noted an important outcome of the research was the establishment of complex climatic patterns to determine what the influence of the weather conditions in the virus populations' behavior is. It also revealed the vector's variation patterns and response to climatic changes.

Based on the scientific results of the study, the strategies used in the management of citrus plantations in Cuba were modified taking into account among other facts, the virus reproduction rates. This has resulted in a positive impact in the national citrus cultivations, while allowing a more efficient use of resources, said Lochy.

The new management program and the improvement of the epidemiological control system have prevented the outbreak in Cuba of epidemics caused by the black citrus aphid, which is tristeza virus' most effective vector.

The research on the Tristeza virus has been recognized with the national award of the Cuban Sciences Academy in 2006 and by international institutions such as the University of California in the U.S and Brazil's Federal Rural University of Pernambuco.

Of the more than 30 virus and virus-like diseases of citrus known in the world, citrus tristeza virus (CTV) is the most destructive. In 1981, the total world loss attributable to this disease was estimated at 50 million trees. The high degree of efficacy of the black citrus aphid as a CTV vector was demonstrated by the rapid spread of the disease in South America immediately after the introduction of the disease.