Something for the Farmer

A scientific revolution in agriculture is in progress. Examples of high-level science applied to agriculture:

High-Speed Breeding. Trying to develop a blight-resistant kind of oat, Plant Pathologist H. E. Wheeler of Louisiana State University envied the wholesale methods of bacteriologists. When they want a bacterial strain that is resistant to, say, penicillin, they treat a culture containing millions or billions of bacteria with the drug. Only a few may survive, but the survivors multiply rapidly, and soon the culture is alive with the resistant strain.

Plant breeding takes more time. The traditional way is to cross a desirable variety with a wild or primitive type that has high resistance. Among the offspring, crossed and recrossed, may be found a high-yield strain with disease resistance.

The process may take 15 years.

To breed oats resistant to Helminthosporium victoriae blight, Dr. Wheeler decided to copy the method of the bacteriologists. He reports in Science that he sprouted 100 bu. of oats (about 45 million grains), then doused the sprouted seeds with the toxin (poisonous secretion) of the Helminthosporium fungus, and later with the fungus itself. Out of the 45 million, 973 seedlings survived and grew. Thirty days later they were treated with all the other oat diseases, and 471 survived the second ordeal.

In one season, instead of 15 years, Dr. Wheeler got disease-resistant oat seed, which he is holding for further testing. His experiment cost only about 800 man-hours of labor. He thinks it will prove helpful in breeding many kinds of disease-resistant plants.

Internal Insecticide. The U.S. Department of Agriculture announced success with a long-held dream of agricultural chemists: an insecticide that makes the whole plant deadly to insects that try to feed on it. The chemical, called Thimet for short,* was developed by American Cyanamid Co. It is mixed 50-50 with carbon dust, and 8 lbs. of the blend is mixed with 100 lbs. of cottonseed before planting. The cost for an acre of cotton: $3.

When the seed sprouts, the young roots absorb the Thimet, and as the plant grows, the poison spreads through it without doing any harm. But insects that eat the plant or suck its juices die of their poisoned meal.

Many cotton pests, including thrips, aphids, spider mites and cutworms, are controlled by the internal poison. Boll weevils are killed if they show up during the period of the poison's effectiveness, which is three to seven weeks. Big advantage of the internal poison is that it protects the whole young plant, while sprays and dust may leave some parts unprotected.

* Full name: O, O-diethyl S-(ethylthiomethyl) phosphorodithioate.

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