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54 W. J. Turnock
Recommendations
Acknowledgements
Statement 1978, Kostylyova 1979). In the regions where the host is univoltine, T. evanescens
generally is very rare (Prokoreva 1976). It is used as an inundative biological
control agent in the USSR.
The major components of the parasitoid guilds of M. configurata and M. brassicae
attacking the early instar larvae include one ichneumon, B. f1avescens, in Canada; and
two ichneumons, E. cintipes and Microplitis mediator, and one tachinid, E. consobrina,
in western Europe. In Canada. one tachinid, A. cinerea, attacks the late instar larvae of
Mamestra cotlfigurata but no species of comparable effectiveness is reported from Eurasia.
No egg parasitoids occur in Canada whereas T. evanescens occurs at generally low levels
in Eurasia.
The differences in the major components of the parasitoid guilds of M. configurata and
of M. brassicae lead to the following recommendations for parasitoid introductions into
Canada:
(1) Parasitoids attacking the early larval ins tars
(a) Ichneumons: B. f1avescetls in Canada is more effective than either E. cinctipes
or Microplitis mediator in Eurasia. M. mediator does not go into diapause and does not
occur in those parts of the Soviet Union where Mamestra brassicae is univoltine. Neither
E. cinctipes nor Microplitis mediator should be considered for introduction into Canada.
(b) Tachinids: Mamestra configurata does not have an effective species attacking the
early larval instars as Mericia ampe/us is poorly adapted. E. consobrina is an important
parasitoid in Eurasia. It successfully parasitizes Mamestra configurata in the laboratory
(Wylie 1977a) and has potential as a biological control agent. Material for releases in
Canada should be obtained from areas where M. brassicae is univoltine.
(2) Parasitoids attacking late larval instars
In Canada, A. ci1lerea is common, particularly during outbreaks, but no equivalent
species is reported as a major parasitoid of M. brassicae in Eurasia. A. cinerea could
be considered for introduction into the Soviet Union, perhaps as part of an exchange of
material involving E. C01lsobri1la. M. brassicae was a suitable host for A. cinerea in
laboratory tests (Wylie 1977a).
(3) Egg parasitoids
The very low level of egg parasitism in M. brassicae does not suggest that T. evanescens
would contribute significantly to the control of M. configurata in Canada. However, the
local form of T. evanescens reported from the Irkutsk region (Kostylyova 1979) should
be further investigated. If Canada should develop facilities for producing Trichogramma
for inundative release, importation of the "Irkutsk" form would be desirable.
Copies of the cited literature from the USSR were made available through the efforts
of Mr A.1. Sylchenko, Ministry of Agriculture, Moscow, and Dr G. Tsubulskaja,
Ukrainian Plant Protection Research Institute, Kiev. Their cooperation is greatly
appreciated. Dr A.P. Arthur, Agriculture Canada, Saskatoon, kindly permitted the use
of his data on parasitism of M. configurata in Saskatchewan.