Abstract
Biological control of Trialeurodes vaporariorum (Westwood) by Encarsia formosa Gahan was tested during three consecutive
production cycles (16-28 weeks) on a beef tomato (Solanum lycopersicum L.) crop in a glasshouse and a plastic greenhouse on
the Bogota Plateau in Colombia. During the course of this study over the period 1997-1999, the mean temperature was around
16 °C in the plastic greenhouse and around 17 °C in the glasshouse. E. formosa was introduced at a rate of 3 adults per m2 per
week in the 1997 production cycle, and at a rate of 3 and 5 pupae per m2 per week in 1998 and 1999, respectively. In 1997, the
adult whitefly population increased exponentially to a peak of 76 adults per plant in the plastic greenhouse, while the whitefly
population in the glasshouse reached a peak of only 12 adults per plant. The percentage parasitism fluctuated between 42 and 82%
in the glasshouse and between 28 and 47% in the plastic greenhouse. In 1998, the T. vaporariorum population could not be
brought under control in both greenhouses and reached a peak of 80 and 53 T. vaporariorum adults per plant in the plastic greenhouse
and the glasshouse, respectively. Parasitism fluctuated between 55 and 97% in the glasshouse and between 32 and 84% in
the plastic greenhouse. In 1999, biological control was successful in both greenhouses. Most of the time, populations of T. vaporariorum
were lower than 1.2 adults per plant and parasitism by E. formosa was 80% or higher. We suggest that the higher temperature
is the main reason for better parasitism in the glasshouse when compared to the plastic greenhouse. The successful results
of 1999 show that biological control is possible under the short day and low temperature conditions of greenhouses situated in the
high altitude tropics such as the Bogota Plateau. Recommendations are given for the application of E. formosa based on the results
of these experiments.
Original language | English |
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Pages (from-to) | 43-57 |
Journal | Bulletin of Insectology |
Volume | 61 |
Issue number | 1 |
Publication status | Published - 2008 |
Keywords
- parasite-host relationship
- commercial glasshouse
- population-dynamics
- aphelinidae
- aleyrodidae
- netherlands