The state of commercial augmentative biological control: plenty of natural enemies, but a frustrating lack of uptake

Augmentative biological control concerns the periodical release of natural enemies. In com- mercial augmentative biological control, natural enemies are mass-reared in biofactories for release in large numbers to obtain an immediate control of pests. The history of commercial mass production of natural enemies spans a period of roughly 120 years. It has been a successful, environmentally and eco- nomically sound alternative for chemical pest control in crops like fruit orchards, maize, cotton, sugar cane, soybean, vineyards and greenhouses. Currently, aug- mentative biological control is in a critical phase, even though during the past decades it has moved from a cottage industry to professional production. Many efficient species of natural enemies have been discovered and 230 are commercially available today. The industry developed quality control guidelines, mass production, shipment and release methods as well as adequate guidance for farmers. However, augmentative biological control is applied on a frustratingly small acreage. Trends in research and application are reviewed, causes explaining the limited uptake are discussed and ways to increase application of augmentative biological control are explored

Egg-laying-site preferences of Pterostichus melanarius in mono- and intercrops

Increased vegetational diversity influences the behaviour of carabid beetles by changing plant-related abiotic factors. These abiotic factors (light, humidity and habitat structure) affect the selection of oviposition sites and egg survival of carabid beetles. In a field experiment, more larvae of Pterostichus melanarius (Illiger) (Coleoptera Carabidae) were caught in Brussels sprout intercropped with barley than in Brussels sprout alone. The influence of the presence of living barley and Brussels sprout plants on oviposition was studied in the laboratory. Also, the effects of wet/dry substrate, light/shadowed and structured/unstructured environment on the number of eggs laid were investigated under laboratory conditions. Results indicate a preference for moist, shadowed, structurally complex environments as egg laying sites. This preference results in significantly higher numbers of eggs laid by beetles in barley compared to Brussels sprout. Vegetation characteristics by themselves may influence egg-laying-site preferences, in addition to the availability of prey for adults and larvae in the different cropping systems. Vegetables intercropped with cereals provide a more favourable microclimate for the reproduction of P. melanarius than vegetables grown alon

Life history parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) at different environmental conditions on two bean cultivars

Life-history parameters of the greenhouse whitefly Trialeurodes vaporariorum (Westwood), an important pest of bean crops in Colombia, were determined in environmental control chambers on two dry bean (Phaseolus vulgaris) cultivars (cv.). Trialeurodes vaporariorum longevity on cv. Chocho decreased as temperature increased from 22.6 d at 19ºC to 5.9 d at 26ºC. Fecundity was significantly lower at 19ºC (8.6 eggs/female), as compared to 22ºC (32.6 eggs/female) and 26ºC (33.3 eggs/female) on cv. Chocho. Fecundity on cv. ICA-Pijao was much higher (127.2 eggs/female) than on cv. Chocho (32.6 eggs/female) at 19ºC. The intrinsic rate of population increase (rm) was highest at 22ºC (0.061), intermediate at 19ºC (0.044) and lowest at 26ºC (0.035) on cv. Chocho, and was 0.072 on cv. ICA-Pijao at 19ºC. Life history parameters of T. vaporariorum are compared to those of one of its natural enemies, the parasitoid Amitus fuscipennis MacGown & Nebeker. Finally, data are presented on the distribution of the parasitoid related to the altitude for the Valle del Cauca, Colombi

Biological control of pests in protected cultivation: implementation in Latin America and successes in Europe

The area with greenhouse crops is estimated to be around 40,000 hectares in Latin America, of which approximately 60% is occupied with ornamentals. Several pests are responsible for losses in yield or quality of greenhouse crops production and pest control is still mainly by chemicals. However, there are several stimuli for the adoption of biological control strategies as an IPM component, not only for the export market of products, but also for increased use of sustainable plant protection methods as a result of the increased success of this methodology in European countries. In Latin America use of native natural enemies plays an important role in pest control and the procedure for development and implementation for biological control in protected cultivation should, therefore, not be based only on the importation and release of commercialized exotic natural enemies. Biological control can be developed making use of effective native natural enemies, or of those introduced a long time ago, and might be supplemented with exotic natural enemies for those pests where native biological control agents are ineffective. In Brazil, the reason for use of native agents is mainly due to concern about environmental risks of imported natural enemies and also because native or naturalized natural enemies are well adapted to local environmental conditions. In many countries, including Brazil, Colombia, Chile, Ecuador, Peru and Mexico, IPM and biological control programs are commercially used or are implemented in pilot greenhouses. Several successes of biological control programs used in Europe will be illustrated

Biological control of Trialeurodes vaporariorum by Encarsia formosa on tomato in unheated greenhouses in the high altitude tropics

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

Plagen bestrijden zonder gif

Boeren grijpen meestal naar de gifspuit als zij insecten uit hun gewas willen verdrijven. Al sinds de negentiende eeuw weten we dat ook insecten dat werk kunnen doen. Professor Joop van Lenteren schetst - grotendeels uit eerste hand - de ontwikkeling van de biologische bestrijding in de landbou

Waar komen plagen vandaan?

Het zijn meestal ‘saaie’ gewassen waarin natuurlijke vijanden zich niet prettig voelen. Kortom: de mens organiseert een gigantische picknick voor vegetarische insecten en maakt het juist onaantrekkelijk voor de natuurlijke vijanden van die insecten. Behalve ‘monocultuur’ zijn er nog enkele andere belangrijke oorzaken van plagen. Zo slepen we onze gewassen over de hele wereld. Het lijkt logisch dat je probeert om de plaagsoorten niet mee te slepen. Toch is dat in het verleden vaak gebeurd, toen men simpelweg niet wist waardoor plagen werden veroorzaak

Does Wolbachia infection affect Trichogramma atopovirilia behaviour?

Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the foraging behaviour (including walking activity and speed) of T. atopovirilia is reported in this paper. Temperature strongly affected T. atopovirilia female walking activity, but Wolbachia infected and uninfected females differed in none of the behavioural components that were measured such as walking activity and walking speed. Walking activity was highest at 25 ºC and differed significantly from that at 20 and 15 ºC. Trichogramma wasps were highly affected at 15 ºC. Behaviour analysis with females showed that female wasps spend most of the time on drilling + ovipositing on host eggs followed by host drumming and walking while drumming. The parasitism rate and number of offspring did not differ significantly between infected and cured Trichogramma females. Biological control implications of these findings are discussed