Author
Martin, Robert | |
TZANETAKIS, I - OREGON STATE UNIVERSITY | |
SWEENEY, M - B.C. MINISTRY OF AGRI | |
WEGNENER, L - SIMON FRASER UNIV |
Submitted to: Acta Horticulturae
Publication Type: Proceedings Publication Acceptance Date: 2/8/2006 Publication Date: 8/31/2006 Citation: Martin, R.R., Tzanetakis, I.E., Sweeney, M., Wegnener, L.A. 2006. A virus associated with Blueberry fruit drop disease. Acta Horticulturae. 715:497-501. Interpretive Summary: During the past few years, a premature fruit drop symptom has been observed in several blueberry fields in Oregon, Washington and British Columbia. The plants flower normally, though the young leaves and flowers have a transient red coloration that is absent in healthy plants. The fruit develops to 3-5 mm in diameter and then aborts so that affected bushes have virtually no fruit at harvest. The incidence within fields increases year to year suggesting that a pathogen is involved. We have not been able to transmit a virus to herbaceous hosts or to purify virus from infected blueberries. Only one of more than 60 attempts at dsRNA purification was successful, which was used for cloning and sequencing. Thus far, approximately 1700 nucleotides of the dsRNA template have been sequenced and two sets of primers for detection were developed. In RT-PCR assays, amplicons were obtained from symptomatic bushes with both sets of primers but not from asymptomatic bushes. The sequence obtained shows homology with fungal and vertebrate rather than plant viruses. In related studies, similar viruses have been obtained from diseased bushes of tomato, redbud and black raspberry. The possibility of a systemic virus-infected fungal pathogen can not be ruled out at this time in any of these cases. Technical Abstract: During the past few years, a fruit drop symptom has been observed in several blueberry fields in Oregon, Washington and British Columbia. The plants flower normally, though the young leaves and flowers have a transient red coloration that is absent in healthy plants. The fruit develops to 3-5 mm in diameter and then aborts so that affected bushes have virtually no fruit at harvest. The incidence within fields increases year to year suggesting that a pathogen is involved. Virus purification and mechanical transmissions to herbaceous hosts have been unsuccessful. Only one of more than 60 attempts at dsRNA purification was successful. Thus far, approximately 1700 nucleotides of the dsRNA template have been sequenced and two sets of primers for detection were developed. In RT-PCR assays, amplicons were obtained from symptomatic bushes with both sets of primers but not from asymptomatic bushes. The sequence obtained shows homology with fungal and vertebrate rather than plant viruses. The most closely related virus in a BLAST search was a Totivirus from Zygosaccharomyces. The possibility of a systemic virus-infected fungal pathogen can not be ruled out at this time. |