The Federal Insecticide, Fungicide, and Rodenticide Act includes 

 microbial materials among the products that must be registered by the 

 U. S. Department of Agriculture before they can be sold interstate. 



To obtain registration of a label, the manufacturer must prove that 

 the material is effective and useful for the stated purpose and is safe 

 when used as directed. Based on evidence submitted by the manufacturer, 

 the U. S. Food and Drug Administration determines whether a residue 

 tolerance should be established, or exemption from need for a tolerance 

 should be granted. State laws that govern local sales usually are patterned 

 after Federal law. 



Man has made great progress in distinguishing the harmful from the 

 harmless in microorganisms. Microbes of no importance to human health 

 and safety are in fresh foods of all kinds and rightly taken for granted. 

 Today's knowledge enables scientists to manage selected types of pest- 

 killing microbes without adverse side effects. 



MASS PRODUCTION 



Microbial source materials are simple and go a long way. In University 

 of California experiments, 5 virus -killed caterpillars were enough to 

 spray an acre of caterpillar -infested alfalfa. Adding 5 dead caterpillars 

 to 5 gallons of water gave each quarter -teaspoon of spray a virus strength 

 of 5 million polyhedra (angular granules that surround virus particles and 

 help protect them from becoming inactive). Each polyhedron contained 

 several virus particles. 



Two known ways of getting mass production are: (1) To collect or 

 breed insects, infect them with a disease organism, and then put the 

 disease-killed insects through a series of processes; or (2) to grow a 

 disease organism outside its insect host in a culture medium, that is, 

 using chemical nutrients. 



The second way is preferable because it requires less work, and 

 the processes and equipment are better adapted to economical commercial 

 production. 



Some fungi and bacteria can be grown in culture media, either in 

 laboratory containers or in industry's vats of, say, 12,000-gallon capacity. 



For the production of other insect disease organisms, infected insects 

 are the only present sources. Efforts to culture these pathogens in chemi- 

 cal media are being made, but are still in exploratory stages. Typical 

 difficulties encountered have been a scant production or failure of an 

 organism to reproduce dependably after a generation or two. 



Among the sporeforming bacteria that have failed so far to produce 

 spores in practical numbers in artificial cultures are those causing milky- 

 diseases in Japanese beetle grubs. Experiments aimed at finding some 

 satisfactory material on which these spores can be grown industrially 

 have been started at the Fermentation Laboratory of the ARS Northern 

 Utilization and Development Research Division, in Peoria, 111. 



Canadian Department of Agriculture scientists have indicated that 

 they may attempt chemical rearing of nematodes, using techniques which 

 they have developed for experiments in rearing insect parasites in various 

 media. 



