''Contarinia'' (formerly ''Diplosis'' or ''Mayetiola'') ''tritici'' is a small
dipterous
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
insect of the family of
gall gnats. It depredates
wheat
Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...
, to which it is nearly as destructive as the famous and closely allied species, the
Hessian fly. As is typical for agricultural pests, the species is known by a number of common names, including wheat fly, lemon wheat blossom midge, wheat blossom midge, wheat yellow blossom midge, yellow wheat blossom midge, and yellow wheat gall midge.
[The Database of the European and Mediterranean Plant Protection Organization (EPPO]
/ref>
Description
The typical insect is 1/30 of an inch long, orange red, with whitish wings hairy on the edges, and black eyes. They deposit their eggs in the centre of the corolla of the wheat flower, coming out in great numbers between 7 and 9 p.m. early in June, several laying on the same ear. The eggs are hatched in eight to ten days.
The larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
e, footless grubs nearly an eighth of an inch long when fully grown, feed upon the flower, rendering it abortive, and not upon the stem like the Hessian fly. They are yellowish, with sharp head and truncated tail, and have a quick wriggling motion. By the first of August they descend about half an inch into the earth, and remain there through the winter. The pupa
A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...
is narrower, rufous, and sharp at both ends.
History
An insect considered by Harris the same appeared in northern New England about 1828, whence it spread to Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, , and New York
New York most commonly refers to:
* New York City, the most populous city in the United States, located in the state of New York
* New York (state), a state in the northeastern United States
New York may also refer to:
Film and television
* '' ...
, and disappeared only by being starved out by a change of crop or the substitution of late sown spring wheat. (See Harris, ''On the Insects injurious to Vegetation''.)
Treatment
In the late 19th century, the most efficacious remedies were: fumigations with sulphur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...
for several evenings in succession while the grain was in blossom, lime and ashes strewn over them when wet with dew, liming and ploughing the soil into which they have burrowed, and sowing late in spring or early in autumn.
A little black ichneumon fly deposits her eggs within these larvae, and destroys many.
Notes
References
*
Cecidomyiinae
Agricultural pest insects
Diptera of North America
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