| Popis: |
In the last 5 years several trials have been developed under field and semifield conditions in Apulia (southern Italy) to test the effectiveness of different strategies to control the populations of Philaenus spumarius (Ps) and Neophilaenus campestris (Nc) in olive groves. Trials were optimized based on the outcomes (biology, host preference and population dynamics) of a multiyear monitoring program. It is well estabhlished that mechanical interventions for removing the ground vegetation in spring, is one of the best and environmentally sustainable strategies against juveniles. However, we demonstrated that the timing for these interventions is critical to get high suppression efficiency and should be defined locally based on the microclimatic conditions. Nevertheless, a wide range of alternative strategies have been tested: mulching, pyroherbicides, applications of herbicides/insecticides, replacement of the natural ground vegetation, reaching in some cases mortality rates close to 100%. Sowing gramineous (negatively selected by Ps) can contribute to reduce Ps nymphs but not Nc. Among insecticides, neonicotinoids and pyrethoids showed the highest efficacy in the control of juveniles of both species, while other products (i.e. buprofenzin , orange essential oil, kaolin and zeolite) contributed to reduce the nymphs population but showed lower effectiveness. With regard to adults, insecticides are so far the only practical option available. Neonicotinoids and pyrethroids showed the highest efficacy and persistence up to 15-20 and 20-25 days after treatment, respectively. High values of mortality and persistence were obtainded in trials where cyantraniliprole was used. Organophosphate insecticides yielded lower mortality rates or inconsistent results. Good knockdown effect was recorded using spinosad, spinetoram, abamectina and orange essential oil, with a persistence up to 7 days for spinetoram, but with no-persistence in other insecticides tested. Other insecticides, i.e spirotetramat, flonicamid, pymetrozine, buprofenzin, natural pyrethrin and azadirachtin, did not cause significant mortality compared to the untreated controls. As for the juveniles, investigations on the population dynamics in olive groves and other crops, allowed to identify the best timing for insecticides applications. All togheter, the data gathered from the different control strategies tested allowed to define a set of recommended interventions for reducing juvenile and adult spittlebugs. |
