Articles
NEW EXPERIENCE WITH A RESTRICTION OF PLUM POX SPREAD IN PLUM ORCHARDS
At least 6 % of planted trees had been probably contaminated by PPV in the time of planting despite their certification in a nursery after two inspections during the previous season as symptomless.
Most dangerous in this respect seems to be trees originated as suckers from older trees.
On the other hand, a spread of PPV by insect vectors and other ways seems to be much less than it was expected.
The maximum rates of new PPV contamination were about 3 % per year but usually they were about 1 % or less.
Using an early identification of trees contaminated by PPV (by a careful inspection of all trees in a orchard twice per a season) and their immediate discarding afterwards, it is possible to keep the virus disease in plum orchards under control without greater economic losses even with such sensitive cultivars like ‘Domestic Prune’.
A majority of the other studied factors had also more or less influence on rates of new contaminations by PPV. Their practical utilization is recommended or being discussed.
However, in some cases a more long-term study is needed.