Rate of contamination by plum pox virus (PPV) in two plum orchards - one with and the other without removal of infected trees
2000
Blazek, J. | Karesova, R. | Matejsek, J. | Kracmar, Z. (Vyzkumny a Slechtitelsky Ustav Ovocnarsky, Holovousy (Czech Republic))
Spread of PPV was monitored in two plum orchards of similar age. In one orchard the trees showing PPV symptoms were immediately removed by grubbing whereas in the other contaminated trees were marked but left in place. In the orchard in which early elimination of infected trees was enforced, the rate of contamination fluctuated between 2 and 3 % per year. In the other orchard, in which contaminated trees were not removed the health state remained very good for several years. This extraordinarily healthy state of the planting started to worsen only in the sixth year (1995) when 1.6 % of trees were found to be infected by PPV. Since then the percentage of newly contaminated trees increased explosively: 6.5 % in 1996, 19. % in 1997 and 24.3 % in 1998. The rate of contamination was much higher with clones of 'Domestic Prune', where nearly all trees were classified as diseased in 1999.
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