Articles
VIRUS ASSOCIATED WITH SEVERE DECLINE OF PLUM TREES IN POLAND
The inoculated trees developed typical plum pox symptoms on the leaves during succeeding years.
During the third year after inoculation in addition to the typical leaf symptoms, trees of the cultivars "Green Gage2", "Italian Prune", "Kirke’s Blue" and "Dabrowice Prune" developed atypical flattening and longitudinal cracking on one-year-old shoots.
During succeeding years, these trees became severely stunted, the foliage was small and sparse, the trees flowered heavily and many of them developed a severe decline and died.
Forced buds, root tissue and rootstock sprouts from the severely declining trees were used as sources of inoculum for virus indexing on a series os standard indicator host plants.
In addition to the plum pox virus from the original inoculum source, raspberry ringspot virus (RRV), tobacco necrosis virus (TNV), and apple chlorotic leafspot virus (ACLSV) were isolated from the declining trees.
The RRV was isolated most frequently, TNV and ACLSV only occasionally.
It is possible that one or more of these viruses, in association with plum pox virus is responsible for the severe decline of certain plum cultivars in Poland.
Further research is in progress to test this hypothesis.