the label, there is a probability of 97.5% that the specified number is
correct. As mentioned above, the number of samples will affect the
confidence interval of the mites. Similarly, the variation within the
samples is crucial for how narrow the confidence interval will be.
Sex ratio A sample of mites is examined and the numbers of males and
females are counted. The male can be distinguished on its ventral
shield which is not divided, the male has an oval genital opening in
front of the ventral shield. The female has three ventral shields: a
sternal, a genital and an anal shield. Different size of samples results
in different certainty of the sex-ratio determination as shown from an
example in our testing: a sample of 120 mites causes an uncertainty
of c. ± 6.9%, 240 mites causes a certainty of c. ±4.8 %, 480 mites causes
a certainty of c. ± 3.4 %.
Initial design: B. Larsen and J. Reitzel.
Coordinators: J. Vermeulen and S. Mulder (provisional test).
Leptomastix dactylopiiHoward (Hymenoptera: Encyrtidae)
Test conditions
Temperature: 25 ± 2°C
RH: 70 ± 5%
Light regime: 16L : 8D
Quality control criteria
Quantity the number of live adults as specified on the label; a weekly or
batch-wise test.
Adult mortality 10%, based on three containers sampled and n = 500 or more; a
weekly or batch-wise test.
Sex ratio 45% of the number specified on the label should be females; the
sex ratio does not necessarily have to be 45% as long as there are
enough females in the container; a 4-weekly test.
Fecundity 40 offspring per female per 14 days; n = 30 females; an annual test
Description of testing methods
Fecundity Place a single potato tuber with short sprouts and infested by an
ample amount of L3 females of citrus mealy bug, P. citri, in a venti-
lated container. Introduce a single pair of L. dactylopiiinto the con-
tainer. Leave the system as it is for 14 days. By the end of the 14 days,
take out the pair of wasps from each container. Collect emerging
adults of L. dactylopiifrom the 21st day up to the 31st day from the
beginning of the experiment. Calculate the cumulative number of
adults emerging during this period.
Initial design: S. Steinberg and M. Tommasini.
Coordinators: M. Mosti and M. Kole.
290 J.C. van Lenteren et al.