Submitted to: California Strawberry Commission- Production Guidelines
Publication Type: Other
Publication Acceptance Date: November 18, 2007
Publication Date: January 5, 2008
Citation: Martin, R.R., Wintermantel, W.M., Tzanetakis, I.E. 2008. The occurrence, transmission and control of strawberry viruses in strawberry nurseries and production fields. California Strawberry Commission- Production Guidelines. p.166-172. Technical Abstract: A general and rapid plant decline was a major problem for strawberry growers from 2001 to 2004 until the causal agents and vectors were identified and appropriate control measures could be taken. A virus complex that consisted of two whitefly-transmitted viruses and at least one of five aphid-transmitted viruses was identified in the declining strawberries. The whitefly-transmitted viruses did not cause symptoms on their own, but infection with three to four of the aphid-transmitted viruses did cause decline. No specific combination of viruses caused the decline symptoms, but in all cases a virus complex was involved with at least three and up to six viruses present. The aphid-transmitted viruses all have limited host ranges and need to be able to move from strawberry to strawberry to persist at a location. The whitefly-transmitted virus, Beet pseudo yellows, has a broad host range and could persist in weeds or native vegetation near strawberry fields. At this time, it appears that the whitefly-transmitted virus, Strawberry pallidosis, has a narrow host range and likely persists primarily in strawberry. The most critical part of any control strategy is to start with virus-tested planting stock. In areas where plants are maintained in fruiting fields for more than one season and virus inoculum has had a chance to build, vector control in older plantings will be necessary to protect younger plantings. Nurseries should aim to control all viruses; however, controlling the aphid-borne viruses in production fields should give protection from decline symptoms since the whitefly-vectored viruses by themselves did not cause decline.