Detection and Mitigation of Invasive Plant Viruses
Tropical Plant Genetic Resources and Disease Research
2013 Annual Report
1a.Objectives (from AD-416):
Develop and evaluate multidisciplinary biologically-based pest management technologies to reduce the impact of newly discovered or existing invasive plant viruses in Hawaii. Conduct research and outreach activities to minimize the impact of invasive viruses on Hawaii’s agriculture.
1b.Approach (from AD-416):
A well-equipped laboratory at the University of Hawaii (UH) will be charged with the responsibility for detecting new invasive plant viruses and develop integrated management strategies to minimize the impact of the new or existing plant viruses on crops produced in Hawaii. A research team will be organized to maximize the expertise of the University of Hawaii at Manoa (UH) and the Pacific Basin Agricultural Research Center (PBARC) in virus diagnosis, management strategy development and conducting outreach activities to assist farmers in gaining knowledge on newly discovered viruses and then transferring the knowledge to farmers for use in their crop production practices. Formerly 5320-21000-013-06S (05/13).
This research is related to objective 1 of the inhouse parent project which focuses on disease resistance. Citrus has become very important to diversified agriculture in Hawaii. However, it is affected by a number of pathogens that limit its profitability. Diseases caused by viruses are among the most destructive problems in citriculture worldwide and also in Hawaii. Among the virus diseases of citrus is leprosis which is associated with two distinct viruses. Citrus leprosis virus cytoplasmic type and Citrus leprosis virus nuclear type all induce chlorotic/necrotic lesions on leaves, fruit, and branches of citrus. Leprosis is a serious disease of citrus in Brazil, Panama, and other regions of South America, where it primarily affects sweet oranges and mandarins, but can also affect many other citrus crops. The complete nucleotide sequence of a virus infecting ornamental hibiscus (Hibiscus sp.) in Hawaii that causes green ringspots on senescing leaves, was determined from double-stranded RNA isolated from symptomatic tissues. A proteome comparison revealed this virus was 92% identical to Citrus leprosis virus cytoplasmic type 2, a recently characterized cilevirus infecting citrus with leprosis-like symptoms in Colombia. This study represents the first documented case of a cilevirus established in the United States and provides insight into the diversity within the genus Cilevirus.