Differential response among chestnut traditional varieties to the attack of Cydia splendana

Fruit production of Castanea sativa Miller (Fagaceae) in southern Spain is carried out in traditional orchards using a large number of local varieties. The main areas of production are located in the Natural Park of Sierra de Aracena y Picos de Aroche (Huelva) and the Genal river Valley (Malaga). These agroforestry systems have shown a high genetic diversity and represent an example of in situ conservation. In this region, chestnut mainly suffers from attacks by Cydia splendana (Hubner) (Lepidoptera: Tortricidae), whose larvae feed on the fruits, thereby reducing their quality and economic value. The aim of this study was to evaluate the differential response between the chestnut local varieties to the attack of C. splendana. For that purpose, trees from the most representative varieties were evaluated on various farms. In cases where it was necessary, the trees were identified with a set of eight microsatellite markers. The infestation rate of C. splendana (percentage of infested fruits of the total fruits sampled per tree) differed among varieties, indicating a high genetic component in this effect. The results obtained in this study open the possibility of using this differential response in the control of C. splendana.