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production more expensive. But we have to
emphasize that in some parts of the world,
especially in China and some other Asian
countries and in Latin America, insect com-
ponents, such as haemolymph, could be by-
products of the silk industry and thus cheap
and easy to obtain.

Diets with insect additives

Insect additives can be used in different
ways. Sometimes almost the whole host con-
tents are used as scarcely diluted extracts.
The main elements used are whole-body tis-
sue extracts or haemolymph from lepi-
dopterous pupae in artificial diets for
parasitoids. This is the case for larval para-
sitoids, such as the chalcidid Brachymeria
intermedia(Dindo et al., 1997), the ichneu-
monid Diapetimorpha introita(Ferkovich et al.,
1999, 2000) or the tachinid Exorista larvarum
(Dindo et al., 1999), and for oophagous para-
sitoids, such as Trichogramma spp. (for a
review, see Grenier, 1994). Usually silkworm
species (Antheraea pernyi, Philosamia cynthia)

and easily reared insects like Galleria mel-

lonellaare used for these extracts.

Bee extracts or even whole pulverized

bees or bee brood have been added in diets

for coccinellid predators (Smirnoff, 1958;

Niijima et al., 1977, 1986).

Some diets for Trichogrammacontain egg

juice from a natural host (Consoli and Parra,

1996). For the egg parasitoid Edovum puttleri

a homogenate of host eggs (Colorado potato

beetle) was used (Hu et al., 1998).

In hymenopterous parasitoids, teratocytes

play various roles (Dahlman, 1990), mainly

in the exploitation of the host by the para-

sitoid larva, through secretion of digestive

enzymes attacking host tissues or proteins as

food for the parasitoid larva (Falabella et al.,

2000). In vitro, cell products or cell cultures

were also used in lieu of haemolymph or

host factors (Grenier et al., 1994).

Diets devoid of insect components

Very few diets are chemically defined. The

first defined diet concerning a true para-

Quality of Artificially Reared Biocontrol Agents 117

Table 9.1.Proposed parameters for quality control of parasitoids

and predators produced under artificial conditions.

Morphological parameters

Size or weight of last larval instar/pupa/adult

Percentage abnormalities (deformation of wings/abdomen)

Development and reproduction parameters

Duration of egg/larval/pupal stage

Survival rate of egg/larval/pupal/adult stage

Sex ratio – presence/absence of symbionts influencing sex ratio

Fecundity/fertility

Duration of preoviposition/oviposition/postoviposition period

Longevity

Biochemical parameters

Protein, lipid, carbohydrate content

Hormone titre

Behavioural parameters

Predation or parasitization efficiency

Locomotion/flight activity

Host/prey localization capability

Genetic parameters

Genetic variability

Homozygosity rate