Collcmbola 265 



A METHOD FOR REARING MUSHROOM INSECTS AND 



MITES* 



WHILE conducting studies on the biology and control of insects 

 and mites affecting cultivated mushrooms, it was found necessary 

 to rear large numbers of these pests. Various rearing methods were 

 tried, including the use of soil in salve boxes, manure in vials, etc., but 

 none was found more satisfactory than the following: 



The insects and mites, in as pure culture as possible, were introduced 

 in small numbers into fresh 1 -quart bottles of commercial mushroom 

 spawn, and allowed to breed and develop. This spawn is made of 

 chopped straw and manure thoroughly mixed, sterilized in an autoclave, 

 and later inoculated with mushroom mycelium, grown from spores. With 

 incubation at room temperature, the mycelium penetrates to the bottom 

 of the bottles and completely fills the interstices of the medium. This 

 spawn is thus a pure culture and is uncontaminated with molds. Tight 

 cotton plugs are used in the bottle mouths. 



The mushroom mycelium furnishes an excellent food for these mush- 

 room pests, and they gradually eat it out, leaving the original straw- 

 manure medium. Feeding begins at the top of the spawn, and as it 

 progresses, the portion destroyed is sharply differentiated from the un- 

 eaten part. Eggs are laid and the stages develop next to the glass, 

 where they are easily observed with a binocular microscope. In studying 

 the development of any particular eggs or groups of other stages, a 

 circle is drawn around them on the glass with a wax pencil. They are 

 thus readily referred to. 



It is very important that the flies and springtails to be reared should 

 be free from mites, the hypopi of which are often carried on their bodies. 

 Otherwise the mites may breed so rapidly as to destroy the mycelium 

 and perhaps starve the insects. Contamination with molds should also 

 be prevented as much as possible. 



These bottles of insect colonies should be kept in a somewhat humid 

 atmosphere. After the cultures have been developing awhile the insect 

 excreta, as well as bacteria entering with the insects, will usually make 

 the medium moist enough so that further additions of moisture are un- 

 necessary. Most of the rearing experiments were carried on at tempera- 

 tures between 50 and 65 F. as these represent the usual temperature 

 limits of the bearing mushroom houses. 



The following insects have been successfully reared in spawn bottles 

 of this kind: 



Collcmbola. These tiny insects are sometimes rather difficult to rear 



*Reprinted, with slight changes, from an article in Ent. News 40:222, 1929, by C. A. 

 Thomas, Pennsylvania State College. 



