MONITORING OF CHESTNUT MOTHS BY INTRA- AND INTERSPECIFIC SEMIOCHEMICALS

Abstract

The effectiveness of synthetic sex attractants and a compound of plant origin, ethyl-(E,Z)-2,4-decadienoate, to monitor the flight activity of the chestnut moths Pammene fasciana, Cydia fagiglandana and Cydia splendana in southern Italy was evaluated. Field trapping tests were carried out from the end of June to the end of September during 2006 and 2007 in two chestnut orchards. In both years, pagoda traps were baited with rubber septum dispensers loaded with 1 mg of synthetic sex attractants of one of the three species or with 40 mg of ethyl-(E,Z)-2,4-decadienoate. In 2007, Pherocon IIB traps baited with the sex attractant blend of P. fasciana or ethyl-(E,Z)-2,4-decadienoate were also used. In both years, pheromone traps captured a high number of P. fasciana males, a fair number of C. fagiglandana males and no male of C. splendana. The pattern of weekly catches by pheromone traps showed a peak of flight activity between the second and third decade of July and a smaller one at the end of August for P. fasciana and between the second and third decade of August for C. fagiglandana, without substantial variations among trapping sites. Traps baited with ethyl-(E,Z)-2,4-decadienoate allowed for capturing conspicuous numbers of P. fasciana males and females and the pattern of flight activity as monitored by this compound was similar to that by the sex pheromone blend. Failure to capture C. splendana males could be due to a lack of attractiveness of the sex attractant blend used but also to a low presence of this pest, as suggested by visual fruit samplings carried out at the harvest. Captures of female chestnut moths by ethyl-(E,Z)-2,4-decadienoate are of practical interest since they could be used for a more rational application of control means.