PREDATORY MITES RELEASED ON TRANSPLANTS CAN PROTECT GREENHOUSE-GROWN PEPPERS FROM EARLY BROAD MITE INFESTATIONS

Autor: Lance S. Osborne, Peter J. Stoffella, Daniel J. Cantliffe, Elio Jovicich
Rok vydání: 2008
Předmět:
Zdroj: Acta Horticulturae. :229-234
ISSN: 2406-6168
0567-7572
Popis: The minute broad mite, Polyphagotarsonemus latus (Banks), can cause serious damage to peppers (Capsicum annuum) when infestations occur at early plant developmental stages. A first study was set to evaluate biological control strategies during seedling development. Timing of release of Neoseiulus californicus McGregor, a commercially reared predatory mite, was investigated in scenarios of pest and predator presence to simulate preventive and curative strategies of control. Undamaged seedlings were produced when two predators per seedling were released preventively. Curative control strategies were not effective for producing undamaged or broad mite-free transplants. Further studies were carried to evaluate the effectiveness of N. californicus on pepper seedlings that host a few broad mites and are transplanted into the production greenhouse. N. californicus released at different times and densities, and conventional control methods (micronized-sulfur sprays) were evaluated for pest control, plant damage, and fruit yield. Yields of red fruits from plants with four predators per plant released at any of the release times (a week before, at, or four days after transplanting) or with sulfur sprays were not significantly different from an uninfested control treatment. Releases of two predatory mites per plant led to yields similar to the uninfested control only when introductions were a week before transplanting, while later introductions led to serious plant damage and significantly lower yields. Early broad mite infestations in pepper crops grown in greenhouses might be effectively controlled with N. californicus released at early seedling developmental stages in the nursery and at transplanting in the fruit production greenhouse. INTRODUCTION Infestations of broad mite [Polyphagotarsonemus latus (Banks); (Acari: Tarsonemidae)] initiated at early developmental stages of pepper (Capsicum annuum) can lead to severe plant damage in greenhouses where transplants or fruit are produced (de Coss-Romero and Pena, 1998; Gerson, 1992; Weintraub et al., 2003). Seedlings will appear undamaged when they become infested with the minuscule mite a few days before transplanting but they carry the pest to crops transplanted in greenhouses. Biological control programs initiated at early pepper crop stages are disrupted by multiple sprays of the commonly used pesticides (e.g., sulfur, abamectin, and dicofol). Neoseiulus californicus McGregor (Acari: Phytoseiidae), a predaceous mite released on greenhousegrown vegetables for biological control of two-spotted spider mite [Tetranychus urticae Koch (Acari: Tetranychidae)], has been reported to feed on broad mites as well (Castagnoli and Falchini, 1993; Pena and Osborne, 1996). N. californicus can reproduce when feeding on broad mites (Castagnoli and Falchini, 1993). Preventive releases may provide effective pest management as the predator can remain on plants for short periods when prey is absent (de Courcy Williams et al., 2004). This manuscript presents selected results of research that evaluated the use of N. californicus as a broad mite management Proc. IV IS on Seed, Transplant and Stand Establishment
Databáze: OpenAIRE