Science: Antibiotic for Plants

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Scientists often reach worthwhile goals by setting off in the wrong direction. Dr. Alma J. Whiffen of the Upjohn Co. did just that, several years ago. She noticed that Streptomyces griseus, the mold that produces bacteria-killing streptomycin, also produces a substance that is deadly to fungi. She separated it from the "beers" (solution in which the mold had been growing), called it "actidione," and tried it on fungi that cause human diseases.

As a drug to cure human ailments, it proved worthless. The Upjohn Co. gave the new drug to the Michigan Agricultural Experiment Station at East Lansing to see what effect it had on plants. In strong solutions, it killed young bean and oat seedlings. Apparently actidione was good for nothing.

But in the greenhouse near the slain seedlings were some grown-up bean plants badly infected with powdery mildew. Remembering that actidione was supposed to kill fungi (including mildews), the Michigan scientists sprayed them with a weak solution. In 48 hours the mildew disappeared. They made the solution still weaker and tried it on other afflicted beans. It worked like a charm in dilutions as great as one part per million (1 oz. to 7,497 gals. of water).

This week the Upjohn Co. proudly announced that it had something new for agriculture: an antibiotic that might save the lives of the farmer's plants, as penicillin and streptomycin have saved the lives of people.

So far, actidione has been proved only against powdery mildew of beans, tomatoes and roses under greenhouse conditions. But agricultural scientists are excitedly testing it on other plants infected with a long list of other fungus diseases. If actidione kills the smuts, blights, rusts and wilts of the major farm crops, it will have a tremendous effect on the world's food supply: fungi probably steal as much food from man as all the world's insects.