An overview of the ongoing research on Anoplophora chinensis in Regione Lombardia A special focus on Biological control studies and use of Sentinel trees technique Matteo Maspero 1, Franck Hérard 2, Michael Smith 3, Costanza Jucker 4, Giovanni D Angelo 1, Mario Colombo 4, Mariangela Ciampitti 5 and Beniamino Cavagna 6 1. Fondazione Minoprio, Centro MiRT 2. European Biological Control Laboratory (EBCL), USDA, ARS - Montferrier-sur-Lez, France. 3. Beneficial Insects Introduction Research Unit (BIIRU), USDA, ARS - Newark, USA 4. Dipartimento di Protezione dei Sistemi Agroalimentare e Urbano e Valorizzazione delle Biodiversità (DiPSA), UniMI, Italy 5. Servizio Fitosanitario - Responsabile P.O. Sorveglianza fitosanitaria ERSAF - Milano 6. Servizio Fitosanitario - Responsabile posizione organizzativa: Servizi Fitosanitari a Supporto della Competitività delle Imprese Agricole e Sorveglianza sugli Agroecosistemi, Milano A new research project funded for 3 years by the Lombardy Region, will be developed from 2011 through 2013. It will include deeper studies and analyzes selected for their positive impact on the suppression of CLB populations. Finalizing a Biological Control technique to contain the pest, and using Sentinel Trees as a tool for surveying and suppressing the populations of CLB, are our main goals. Biological control In the major CLB infestation around Parabiago, Italy, a gregarious egg parasitoid of A. chinensis was discovered. It was new for science and was described and named Aprostocetus anoplophorae Delvare (Delvare et al., 2004). Since its discovery, it appeared to be the best candidate for biological control of CLB.
During spring 2012, 90 maples (Acer pseudoplatanus) with a diameter at the base of 8-10 cm, were planted in 6 sites (15 trees per site within the same area) of the CLB infestations in Lombardy where Aprostocetus anoplophorae does not occurred yet.
The experimental design of each plot consisted in a central release point containing 5 trees planted fairly close together and 2 concentric circles of 5 trees each. A first circle of 5 trees planted at 5 m from the trees in the release point, and a second circle of 5 trees at 10m from it.
Italy France EBCL-ARS Italy France In September 2012, the 5 trees in the center will receive CLB eggs from females caged in wire mesh screen sleeve cages around the trunk. Then the CLB eggs will be exposed to Aprostocetus females, so that the CLB eggs get parasitized. The weather conditions, with cool nights during September, will induce diapause of the parasitoid larvae in the parasitized CLB eggs. At several dates in June and July 2013, we will use the 10 trees of circle 1 and circle 2 to create a local population of freshly laid CLB eggs as candidates for parasitization by the Aprostocetus individuals emerging from the 5 trees in the center. To get this, we will place CLB females in wire mesh sleeve cages on the trees of circle 1 and 2. Each cohort of CLB eggs will be suitable hosts during at least 10 days for the parasitoid adults emerging from the 5 trees in the center. In this way, we will determine if Aprostocetus successfully goes through diapauses in these experimental conditions, and if it discovers hosts at 5m or 10m distance from point of emergence.
Sentinel trees The sentinel trees method is based on the use of highly attractive tree species (e.g. Acer saccharinum) for an attract and kill purpose, to monitor pest presence and suppress its populations in areas where infestations are developing, or in sites that previously harboured pest populations. The attract and kill technique is particularly suitable for areas that are difficult to monitor. In two sites, in Brescia province, at Montichiari and Gussago, rows of 50 maples each one (Acer saccharinum) were planted. Aerial view of the site at Montichiari (BS) where a row of sentinel trees was planted Sentinel trees The primary objective will be to attract beetles and kill them by spraying an insecticide on the trunk. The killing agent would simply be applied to the lower 50cm of the trunk where adult CLB lay eggs. The objective would be to kill beetles prior to oviposition. Killing beetles that are attracted to and land on the sentinel trees gives this strategy its name, Attract-and- Kill.