INTRACELLULAR SYMBIOSIS IN COCKROACHES. I. PRODUCTION OF APOSYMBIOTIC COCKROACHES

Abstract

1. The trans-ovarial inheritance of fat-body intracellular symbiotes in the German cockroach was prevented by subjecting the parent insects to high temperature or by feeding the parents aureomycin or sulfathiazole. 2. The most certain and simple method of obtaining aposymbiotic nymphs is by feeding the parents ground dog biscuit plus 0.1% aureomycin all of their lives. 3. Aposymbiotic nymphs are practically incapable of growth on a natural diet which is adequate for symbiotic nymphs. 4. The addition of large amounts of dried brewers yeast to the diet enabled the aposymbiotic nymphs to grow to maturity in two to three times the period required by normal nymphs. 5. Adult aposymbiotic cockroaches suffered impaired reproductive ability. The males were affected as well as the females. 6. The second and third generations of aposymbiotic roaches are similar to the first in both histology and behavior.