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Since the sting stock is reared under near-

natural conditions we do not expect

deterioration. However, once a year we assess

in the laboratory the [quality control]

parameters and, in addition, we measure the

field efficacy (percentage parasitism). Since we

know from our previous experiments that a

change of quality attributes does not occur (or

is not measurable) within the first generations

on E. kuehniellaeggs, we quantify the

parameters only once a year. The sixth

generation (F6) is normally sold to the

farmers... A few rapid tests (parasitism,

emergence, and sex ratio) are made on each

batch when the parasitised eggs are shipped

immediately... The final user (the farmer) is

in general not able to do any performance tests.

Therefore, government institutes, with

financial support of the Trichogramma

producers, accomplish the tests.

Bigler (1994) concludes that:

Quality control in Trichogrammamass-rearings

is one of the measures used to avoid failures in

biological control with these parasitoids. The

extremely artificial rearing conditions,

compared to the habitat where they are

released, call for the establishment of

sophisticated quality control concepts... The

importance of single performance attributes

has to be established and related to field

performance. The methods must be quick,

simple and reliable. A single trait will never

predict the overall performance accurately and

therefore, the best combination of a set of

laboratory methods must be developed.

Whereas performance of the parasitoids in the

field is the best indication of a good rearing

system, low field efficacy does not tell us the

causes. Regular performance control, carried

out in the laboratory, will either indicate

deterioration of performance and initiate

corrections, or make us confident to produce

wasps that are within the quality specifications.

This work by Bigler’s group has initiated the
development of the Trichogrammaguideline,
as presented in this chapter. There have been
various attempts to simplify the quality
control tests for Trichogramma(see, for exam-
ple, Chapter 1, section ‘State of affairs con-
cerning application of quality control
worldwide,’ and the work of Greenberg
(1991) and Silva et al.(2000)), but without
result. On the other hand, the guideline
developed by Bigler’s group has been used

successfully by Hassan and Wen Qing Zhang

(2001) to measure variability in the quality of

Trichogramma sold by several commercial

suppliers in Germany.

Currently Used Quality Control

Guidelines

The history of mass production and quality

control of natural enemies is described in

Chapters 1, 11 and 12. The current situation

concerning quality control in North America

and Europe is presented in Chapters 14 and

15, respectively. Recent developments and

collaboration between natural-enemy pro-

ducers and scientists in North America,

Europe, Australia, New Zealand and South

Africa have resulted in harmonization of

quality control guidelines. Although some

producers have applied quality control in

one form or another for more than 30 years,

the real catalyst for designing guidelines was

a European Community (EC) Concerted

Action that made it possible to organize a

series of meetings with representatives from

industry and academia (van Lenteren, 1998;

van Lenteren and Tommasini, 1999). During

five EC-funded workshops in the 1990s, and

later at meetings under the umbrella of the

International Biocontrol Manufacturers

Association (IBMA) and the Association of

Natural Bio-control Producers (ANBP), qual-

ity control guidelines were written for the 30

species of natural enemies that are most

often used in commercial biological control

(Table 19.1), and these have been tested and

adapted by commercial producers of biologi-

cal control agents. These guidelines cover

features that are relatively easy to determine

in the laboratory (e.g. emergence, sex ratio,

lifespan, fecundity, adult size and preda-

tion/parasitism rate). Recently, IBMA and

ANBP have taken the initiative to update

and further develop quality control guide-

lines.

The guidelines described in this chapter

refer to product-control procedures, not to

production or process control. They were

designed to be as uniform as possible so that

they can be used in a standardized manner

by many producers, and elements of the tests

Quality Control Guidelines for Biocontrol Agents 267