Infection of Macrosiphum euphorbiae with mycelial preparations of Erynia neoaphidis in a greenhouse trial

Experimental preparations (alginate granules and mycelial mars) of the ento mopathogenic Eynia neoaphidis were assessed for their capacity to cause inf ections in populations of Macrosiphum euphorbiae on pepper plants, in a gre enhouse trial performed over 14 d. The dried preparations contained hyphal cells, which upon rehydration produced conidiophores and ejected ballistosp ores. Applications of alginate granules and mycelial mars on soil were more rapid in causing infections in the host population compared with foliar ap plications. On the last sample date, infection rates of 10-14% were obtaine d with foliar applications of E. neoaphidis as alginate granules and myceli al mars, respectively. With soil applications of E. neoaphidis granules and mars, infections were 23-36% after 14 d. From all sample dates, 183 cadave rs were found on pepper plants treated with E. neoaphidis and 37 (= 20%) ex hibited external sporulation after overnight incubation. Comparisons were also made with single foliar sprays of Beauveria bassiana (Mycotrol WP(R)) and the systemic insecticide pymetrozine (Chess WP(R)), th e latter being the only treatment to significantly reduce aphid numbers dur ing the trial period. Treatment with B. bassiana resulted in good initial i nfection rates (50-60%) which declined over the period and reached the same infection level as E. neoaphidis treatments at the end of the trial. With B. bassiana, a total of 81 cadavers were found, of which 62 (= 77%) sporula ted.