Trichogramma.xlsx

On the one hand, Trichogramma spp. individuals were obtained from commercial product Tricholine®Buxus (Bioline AgroSciences). On the other hand, to obtain box tree moth egg masses, adults, and immature stages of C. perspectalis were obtained from fieldwork during 2019 in Mallorca (Balearic Islands, Western Mediterranean, Spain), introduced in entomological tends and reared under semi-field conditions. Immature stages were fed with Buxus microphylla specimens, which were watered daily, and adults were transferred to a new entomological tend and fed with honey – water mix (1:5). The day before the experiment, a new Buxus microphylla was introduced in the entomological tend together with adults to obtain egg masses less than 24h. Finally, the number of Cydalima eggs available for parasitism per treatment was checked before experiment, showing no statistically significant differences between the number of Cydalima eggs available for each treatment (p-value = 0.51).<br>The experiment was conducted the 22nd July in experimental site located at the University of the Balearic Islands (Western Mediterranean Archipelago, Spain). Six B. microphylla were artificially infected with leaves with egg masses (N per tree = 15 egg masses; Ntotal = 90 egg masses). A total of fifteen egg masses were distributed in each Buxus: five at the bottom, five at the middle and five at the top of the potted Buxus plant. The leaves with egg masses were carefully fixed with pins on the leaves of the potted plant without removal any wing scale deposited by the females C. perspectalis during oviposition (Göttig &amp; Herz, 2016). Buxus individuals were kept in entomological tends in semi-field conditions. Then ~10,000 individuals of Trichogramma per plant were released in three Buxus, infected artificially with egg masses, following Bioline AgroSciences indications (Figure 1). After 48h, each egg mass was carefully introduced in individual cardboard boxes until analysis. Egg masses were observed at stereomicroscope to obtain the following parameters: number of Cydalima larvae developed, number of eggs parasited (those parasitized eggs turned black), and number of emerged parasites.<br>The percentage of Cydalima larvae developed was used as indicator of host viability. Likewise, analyses included: the percentage of parasitized egg masses with at least one parasitized egg and the number of emerged wasps.<br>