Abstract:
The larch wooly adelgid
Adelges laricis is an important pest due to
his attacks, especially against the nurseries
and young trees and the horse chestnut leaf
miner Cameraria ohridella which attacks
the leaves of the Aesculus hippocastanum
L., that produces trees defoliation, there
growth slowing down and finally there
drying.In the management of the larch
wooly adelgid, in the lab tests, the microbial
products Laser 240 SC and Milbeknock and
the vegetal one NeemAzal T/S, had a high
efficacy against the young larvae of Adelges
laricis (98-100%) and more reduced against
the older larvae (60-98%). The product
Laser 240 SC, that acts more by ingestion as
by contact, has lesser efficacies against
older larvae. In the experiments on trees all
bio pesticides had high efficacies. It is
recommended the application of the
treatments at the beginning of the infestation
when the young larvae appear. In the
management of the chestnut tree leaf miner
Cameraria ohridella the use of Laser 240
SC and NeemAzal T/S by spraying, the
leaves attack was between 20-30%,
comparatively with 80% for the untreated
witness. Because they are 3-4
generations/year, the treatments must be
fulfilled in the eggs laying periods and
during the neonate larvae apparition, in
order to obtain high efficacies. The
treatments by painting with NeemAzal T/S
reduce the mining larvae number and also
the attack’s degree on the leaves. After 35
days from the treatment its take place a
rising of the attack due to the pressure of the
next generation therefore another treatment
is necessary. The treatment on the bark is
recommended for the residential areas and
parks because the spraying treatments are
harmful for the mean’s health.
