The use of beneficial insects to help control greenhouse pests continues to increase. Growers are continually looking for ways to efficiently and effectively control their pest problems. Integrated pest management (IPM) uses biological control agents as an alternative to, or in conjunction with compatible pesticides.
Greenhouse pests reside in an ideal environment in which to live and breed; and an abundant supply of plant material on which to feed. Such conditions can result in rapid multiplication of pests which, until now, has required regular and routine spray programs. Intensive spray programs have often led to the development of strains that are resistant to the active ingredients that are being applied.
Beneficial mites and insects are effective partners with chemicals, for use in IPM programs – programs that also take into consideration chemical choice, usage and the growing system. Any use of beneficial insects has to be carefully planned, by understanding each greenhouse/nursery (pests, diseases, growing systems, rotations, etc.) and its particular problems. The better the understanding of all of these parameters, the better the results will be.
The first step to a successful program is to think about the growing system and anticipated pests and diseases from past growing seasons. Once this is done, natural enemy usage can be planned.
The second step is to use the correct natural enemies which are of consistent quality, and provided in the best delivery system. The change to an IPM program is sometimes a difficult transition to make and the grower must be motivated. Growers are often motivated because there are problems using existing pest control methods or because of increasing demands by the market.
Beneficial insect use has to be integrated into the operation of the greenhouse and a number of parameters have to be taken into account. They include:
- Pests and diseases that may occur
- Production system, plant varieties, rotations, environmental conditions, etc.
- Chemical controls available
- Chemicals used during the past 3-4 months. (Some chemicals are quite residual, and can affect the establishment of the beneficials).
- Vegetation surrounding the crop
- Origin of the plant material. (Some plants can arrive with pests and disease).
Careful attention to detail can ensure that an IPM program starts successfully, and results in a quality crop.