The objective of this study was to find resistance in wheat cultivars
to the wheat midge (Sitodiplosis mosellana [Gehin]). A total of 61 spr
ing and 61 winter wheats were assayed in 1992 to 1994. Thirteen select
ed cultivars were planted in 1994. Three kinds of apparent response to
midge infestation were found. Eight winter wheat cultivars suffered n
either the usual typical kind nor high numbers of shrivelling of the s
eeds often attributed to the midge, but produced instead small numbers
of shorter and more rounded (tubby) seeds which could be due to midge
activity. Cultivar RL5708 differed from all other cultivars in that i
t showed low proportions of damaged seeds, which were often associated
with dead midge larvae. The third group included lines and cultivars
showing the typical shrivelling of the seeds due to the wheat midge. I
n 1993 most late-planted spring wheat cultivars were less affected by
the midge than the same cultivars planted earlier probably because of
asynchrony between times of wheat flowering and midge oviposition. The
incorporation of resistance to the wheat midge into hard red spring w
heats should contribute to a reduction of wheat losses in years when w
heat midge are abundant.