Los Banos Rotary Club History
Plant Physiologist Explains Use Of New Chemicals

The new and amazing use of chemicals to control the life and actions of agricultural plant life for the betterment of the grower was explained to members of the Rotary Club Tuesday noon by Rene Blondeau, physiologist attached to the agricultural Research Division of the Shell Development Co., Modesto.

Explaining his work as similar to a plant mechanic, Blondeau said he and his fellow workers are primarily concerned with what goes on in a plant to make it grow and bear fruit, and to develop synthetic hormones that will vary the normal processes of nature.

An example of the commercial value of such experimentation and finding is illustrated in a newly developed spray to control pre-harvest drop of apples, pears and other fruits. A synthetic hormone chemical was developed a few years ago to be sprayed over the trees previous to harvesting and the fruit does not fall off before fully ripening. This one development has already saved more money for apple growers than the total amount of funds expended by the U.S. Department of Agriculture for research.

Another illustration of the value of synthetic hormones is a chemical developed for tomato growers, which causes the profitable first blossoms to set fruit. Otherwise, when nighttime temperatures fall below 57 degrees, the first blooms too frequently fall off.

Plant physiologists know, Blondeau said, that plant leaves produce a small amount of natural hormones, and when they grow old, they wither, die and fall off because their natural manufacture of hormone has ceased. By reversing the process, and spraying anti-hormones on green leaves, they are now seeking to cause premature dropping of leaves on cotton plants. This would permit orchardists to strip their trees and do their winter pruning before bad weather sets in; would permit cities to clean up the fall leaves from the streets before start of the rainy season, and provide other benefits. Peculiarly they have found that when leaves fall early in the fall the blossoming time the following spring is delayed accordingly; thus the early defoliation of almond trees could postpone the following blossoming period until most danger of frost had passed.

Experimental work is also underway seeking new hormones or anti-hormones to defoliate cotton; to serve as new and more efficient weed killers, to cause more uniform and quicker growing of fruits, and otherwise aid the farmer and orchardist in growing a better product and hurrying or delaying the harvesting period to take advantage of market prices.
Blondeau concluded his talk with a question and answer program, with many inquires fired at him by his listeners. He was introduced by program chairman Dr. L. R. Hillyer.

April 2, 1954

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