Author
SUSAIMUTHU, J - NOBLE FOUNDATION, OK | |
TZANETAKIS, I - OREGON STATE UNIVERSITY | |
GERGERICH, R - UNIV OF ARKANSAS | |
KIM, K - UNIV OF ARKANSAS | |
Martin, Robert |
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/15/2008 Publication Date: 8/15/2008 Citation: Susaimuthu, J., Tzanetakis, I.E., Gergerich, R., Kim, K.S., Martin, R.R. 2008. Viral interactions lead to decline of blackberry plants. Plant Disease. 92(9):1288-1292. Interpretive Summary: Increasing demand for fresh fruit and development of improved cultivars have led to an increased popularity of blackberries in the United States. Blackberry yellow vein disease (BYVD) has emerged as a threat to blackberry production the past few years, primarily in the southern United States. The disease results in severe symptoms that are characterized by the yellowing of veins of primocane leaves, with the newly emerging leaves initially symptomless. Symptoms usually vary with cultivars in different regions but vein yellowing and die-back of fruiting canes are associated with this emerging problem. Blackberry yellow vein associated virus (BYVaV) was thought to be the sole cause of BYVD. However, BYVaV has recently been found in several symptomless blackberry cultivars, so symptomatic plants were reevaluated for infection with additional viruses. An unusual member of the family Potyviridae has been identified from symptomatic plants and named Blackberry virus Y (BVY). BVY has been shown to spread in the field and cause BYVD when co-infected with BYVaV. Both viruses are asymptomatic in single infections but are readily detectable by RT-PCR. Although BYVaV has been consistently associated with BYVD in different geographical regions, the detection of BVY has thus far been restricted to northwest Arkansas. It has been hypothesized that BYVaV is the synergistic determinant of BYVD that causes symptoms in different cultivars at various locations during co-infection with other viruses. Investigations into mixed infections in other areas are being carried out. Technical Abstract: Blackberry yellow vein disease (BYVD) poses a new threat to the blackberry industry in the United States. Symptoms usually vary with cultivars in different regions, but vein yellowing and die-back are associated with this emerging problem in northwest Arkansas. Blackberry yellow vein associated virus (BYVaV) was thought to be the sole cause of BYVD. However, BYVaV has been found in several asymptomatic blackberry cultivars. An unusual member of the family Potyviridae has been identified recently from symptomatic plants and named as Blackberry virus Y (BVY). BVY has been shown to spread in the field and cause BYVD when co-infected with BYVaV. Both viruses are asymptomatic in single infections but are readily detectable by RT-PCR. On the other hand, mixed infections lower the titer of BYVaV, sometimes to levels undetectable by RT-PCR, while the concentration of BVY increases several-fold. Electron microscopy revealed a variety of viral inclusions in symptomatic leaf samples but none could be found in single infections. Although BYVaV has been consistently associated with BYVD in different geographical regions, so far the detection of BVY has been restricted to northwest Arkansas. It has been hypothesized that BYVaV is the synergistic determinant of BYVD that causes symptoms in different cultivars at various locations during co-infection with other viruses. |