This paper summarizes tests of the mating disruption technique to control Codling Moth (Cydia pomonella L.) and the Apple Leafrollers Complex (Adoxophyes orana, Argyrotaenia pulchellana, Archips podanus, Archips rosanus, Pandemis cerasana and P. heparana) performed during last three years in Italy.
The method was applied on 40 hectares in 1988, 60 ha in 1989 and more than 80 ha in 1990. The
... [Show full abstract] trials included apple, pear and kiwi orchards.
Dispensers were applied at the rate of 200-400 per hectare corresponding to 60-120 g/ha of pheromone.
Diffusion rate of the pheromones wwas estimated by weighing and GLC analysis of dispensers exposed both in orchards and in climatic chamber. effect of antioxidant and UV screener dosages were also evaluated.
Codling Moth control requires in most cases two applications per year while for Leafrollers a single treatment can assure a satisfactory protection. When these pests are present at the same time, a single dispenser containgi both pheromones may be conveniently used.
Orchard size and pest population density have been identified as the most important factors limiting the feasibility of mating disruption.
Generally, good natural control was set up on mites and leaf miners, while aphids and Pear Psylla often required treatments with selective or "soft" chemicals; serious problems arise from Oriental Fruit Moth attacks on apples and, in larger amounts, on pears.
Another aspect we observed was the inadequate disruption by Z11-14:Ac on Leafrollers having high ratio of E/Z isomers, such as Pandemis cerasana and Archips podanus; on the contrary the total confusion of A. orana by Z11 isomer alone was confirmed.
The results up to now obtained allowed us to draft some recommandations for a successful application of the mating disruption technique.
