Potential of Chrysoperla externa (Hagen) at B-biotype Bemisia tabaci (Gennadius) nymphs control in tomato plants - DOI: 10.4025/actasciagron.v29i1.62

Abstract

This study aimed to evaluate the potential of Chrysoperla externa (Hagen, 1861) in controlling nymphs of Bemisia tabaci (Gennadius, 1889), biotype B, in tomato plants. Ninety-six pots, each with one whiteflyfree plant, were placed in cages at greenhouse and each plant was infested with 100 adult whiteflies for 24 hours. In the first and eighth days after nymph eclosion, infested plants were inoculated with one, five and ten larvae of the first, second and third C. externa instars, excepting the control plants. The number of nymphs that escaped predation was counted on the eleventh day after prey eclosion. Totally casualized delineation was used, with 3 x 4 factorial scheme and eight repetitions. The C. externa larvae released in the first day after whitefly nymph eclosion were most efficient in reducing prey population at 10 larvae per plant, ensuring roughly 50% pest control. When released on the eight day after nymph eclosion, at densities of five and ten C. externa larvae per plant, a pest density reduction of approximately 40% was observed. Therefore, releasing C. externa larvae on tomato plants kept individually in cages is efficient to control B-biotype B. tabaci