Autori: Vidal, E., L. Zagrai, S. Milusheva, V. Bozhkova, E. Tashevaterzieva, I. Kamenova, I. Zagrai, M. Cambra

Editorial: Ann Appl Biol , 162, p.299-308, 2013.

Rezumat:

The application of horticultural mineral oil (HMO) treatments has been
reported as a possible control strategy to reduce Plum pox virus (PPV) incidence
in Prunus nurseries. The effect of Sunspray Ultrafine HMO at 1% on the
natural viral spread was evaluated in experimental nursery plots of Nemaguard
and Mariana GF8-1 Prunus rootstock blocks established under high natural
inoculum pressure of the most prevalent PPV-types. Tests were conducted
in experimental nursery plots in Plovdiv, Bulgaria (PPV-M and PPV-Rec),
in Bistrita, Romania (PPV-D and PPV-Rec) and in Ll´ıria, Spain (PPV-D).
Horticultural mineral oil treatments were applied weekly during the vegetative
period from spring to fall (treatments were interrupted in the summer).
Nursery plants were analysed yearly by double-antibody sandwich enzymelinked
immunosorbent assay with 5B-IVIA/AMR monoclonal antibodies. The
population dynamics of the aphids visiting plants in each experimental nursery
plot was monitored by the sticky-shoot method and also by Moericke yellow
water traps. At all three locations, the aphid population first peaked in the
springtime. Furthermore, a variable second peak of aphid population was
observed in Plovdiv and Bistrita in autumn. The treatments reduced PPV
incidence in the three experimental locations and plots and in both assayed
Prunus rootstocks grown under high PPV-inoculum pressure. A reduction from
10% to 20% of PPV-incidence between treated and control plants (P<0.05) in Plovdiv and Bistrita, respectively, was observed at the end of the tests. However, HMO treatments did not prevent PPV infection altogether, probably because of the high PPV prevalence in the area near the experimental nursery blocks. The control of PPV in nursery blocks based on HMO is presented as an environmentally friendly strategy based on the physical action of the treatments.

Cuvinte cheie: Aphid population peak, HMO, local prevalence, nonpersistent virus, spray, virus spread.