Ataques de traça da uva Lobesia botrana em diferentes castas das regiões dos Vinhos Verdes e Douro

The European grape berry moth Lobesia botrana Denis & Schiffermüller (Lepidoptera: Tortricidae) is responsible for direct losses due to the damage cause to the grapes and indirect losses by allowing access to the grey mould Botrytis cinerea Pers. In some varieties – as Touriga Franca – the attacks are always more intensive than with other varieties. In this work, bio-assays have been performed to test the oviposition’s behaviour of L. botrana female. Three varieties of Vinhos Verdes region – Arinto, Loureiro and Trajadura – and three varieties of Douro region – Barroca, Touriga Franca, Touriga Nacional – have been tested. Only Touriga Franca presented significantly difference being more attractive. The bio-assays partially elucidate field observations and denounce a possible existence of alelochemicals in grapes berries