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BIOLOGICAL PEST
CONTROL IN EURASIA This broad region
has traditionally experienced pest organisms of native origin which are
managed in a variety of ways that do not usually include classical biological
control. With the exception of certain Mediterranean areas, classical
biological control is not practiced. There is considerable emphasis on the
deployment of pathogenic organisms, and on augmentation with parasitoids,
especially in glasshouse culture. The preservation of naturally occurring
predators and parasitoids is also emphasized. Nevertheless, there are real
possibilities for the incorporation of classical biological control tactics,
especially against invaded pests such as the Colorado potato beetle,
synanthropic flies and cockroaches, as well as exotic weeds. Development and
application of biological control in Europe was reviewed by Franz (1961a,b),
Franz & Krieg (1972), Greathead (1976), Hagen &
Franz (1973), Hussey & Scopes (1986), van Lenteren (1986) and van
Lenteren & Woets (1988). According to
these authors, an initial practical demonstration of biological control in
Europe was in France in 1840. M. Boisgiraud released the carabid Calosoma sycophanta (L.) against the gypsy moth, Lymantria dispar (L.) on poplars. At the same time in Germany, J. R.
C. Ratzeburg moved heavily parasitized Dendrolimus
pini (L.) into an outbreak
area and recommended the use of ants, Formica
rufa group, against forest
defoliators. The method of artificial colonization of forest ants has been
studied extensively in the 20th century (Greathead 1976). Also efforts to
increase insectivorous bires by providing nesting facilities were common in
Europe, and the ant and bird work are specific elements in the European
pattern of biological control (Franz 1961b). Conservation of natural enemies
had been suggested in Europe as early as 1827 by G. L. Hartig. Many attempts
to augment existing natural enemy populations were made thereafter, often an
a local scale. Most are inadequately documented and, therefore, are not
treated in any detail here. The earliest,
and unsuccessful, attempt to colonize a natural enemy in Europe was the
importation of the acarid predator Rhizoglyphus
phylloxerae (Riley *
Planchon) in 1873 for control of the grape phylloxera, Viteus vitifolii
Fitch. The first successful use of exotic organisms was in 1897 when Rodolia cardinalis (Mulsant) was imported to Portugal for control
of cottony cushion scale, Icerya
purchasi Maskell, following
its first appearance in Europe in the previous year. This ladybird beetle was
later introduced to other European countries and the success strongly
stimulated interest in "classical" biological control. Several
other coccinellids were introduced against a variety of pests, but these
programs were less successful. The first
introduction of a parasitoid dates to 1906 when Berlese imported Prospaltella berlesi (Howard) against
mulberry scale Pseudaulacaspis
pentagona (Targ.) (Berlese
& Paoli 1916). The failure of the 1926-1944 campaign to control the
Colorado potato beetle, Leptinotarsa
decemlineata (Say), tempered
enthusiasm for biological control in Europe. Apart from Rodolia, classical biological control in Europe has not
been very successful. The main reason is that Europe has few imported pests.
Simmonds & Greathead (1977) estimated that more than 60% of the 200
insect pest species in the United States were imported, whereas very few
arthropod pests were imported to Europe. The rationale that biological
control will be most successful in situations where natural enemies are
imported from abroad, against pests which were also imported, is obviously
hampering further attempts. Van Lenteren et al. (1987) have shown that all
combinations of exotic and native natural enemies and pests are worth
considering. One notable
exception to a number of failures to deploy exotic natural enemies against
exotic pests was Speyer's success with the parasitoid Encarsia formosa
for control of Trialeurodes vaporariorum in glasshouses
(Speyer 1927). This parasitoid is still commercially used on a large scale, and
forms the focal point of integrated pest management for glasshouses (van
Lenteren & Woets 1988). The use of native natural enemies for biological
control during the first part of the 20th century was summarized by
Sachtleben (1941) and Greathead (1976). Since Greathead's (1976) review a
number of native natural enemies have been evaluated and selected for
biological control and are used commercially (van Lenteren et al. 1987). Interest in biological
control in Eurasia diminished with the appearance of synthetic pesticides
after 1940, but the development of resistance and the recognition of unwanted
side-effects during the 1950's revived biological control somewhat, leading
to the formation of the International Organization for Biological Control
(IOBC) in 1956 (now called the Western Palearctic Regional Section of the
IOBC). This European section of the IOBC has been the driving force behind a
change of thinking in crop protection since, and coordinated many cooperative
biological control projects. Inundative
releases of natural enemies were first undertaken in Russia in 1913 with the
mass rearing and periodic releases of Trichogramma.
However, inundation has not been used on as large a scale in western and
southern Europe. Such releases have figured prominently in the attempt to
control olive fly, Dacus oleae (Gmel.), using Opius concolor Szépl. (Liotta & Mineo 1968). In Italy O. concolor was successfully deployed during the 1960's but
its status is presently (1992) unknown. Another major program with inundation
involved Trichogramma.
Schieferdekker (1970) reviewed this work. The first experiments date from the
1920's (Voelkel 1925), but most work was discontinued and rated unsuccessful
(Greathead 1976). In 1992 there is one project where Trichogramma evanescens
seems commercially successful in the control of Ostrinia nubilalis.
The most important development in augmentative releases in western Europe
have been in glasshouses. However, recent work by Sherif Hassan at the
Bundesanstalt für Biologische Schädlingsbekämpfung in Darmstadt, Germany
shows great promise for field vegetable crops (see references). Eurasia has
served as an important geographic area for export of natural enemies
principally to the United States and Canada for more than a century (Clausen
1978, Greathead 1976). Collection and exploration of natural enemies has been
the area of activity of the Commonwealth Agricultural Bureau's International
Institute of Biological Control (CIBC), the European Parasite Laboratory of
the U. S. Department of Agriculture, and the Commonwealth Scientific and
Industrial Research Organization (CSIRO) in Australia. REFERENCES: <bc-62.ref.htm> & <pooled.htm> [ Additional references may be
found at MELVYL
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