Effects of Beta-Naphthoxyacetic Acid on Fruit Size in the Marshall Strawberry

Abstract

1. The action of beta-naphthoxyacetic acid on the growth of strawberry fruits subsequent to flowering has been studied. Applications of this chemical in the form of sprays applied some time after pollination gave significant increments of fruit size. From a series of tests begun on May 24, the following increments over controls were obtained: 10 p.p.m., no increase; 25 p.p.m., 16.5% increase; 50 p.p.m., 32.7% increase; and 100 p.p.m., 25.9% increase. A second series of tests set up on June 12 produced similar results except that the percentages of increase were somewhat lower. 2. Under the conditions of these experiments no harmful effects from the sprays were noted on either the fruits or the plants. This was true even of sprays applied in fairly high concentrations. 3. Although the results obtained are indicative of possible field and commercial significance, additional work must be done before the use of the chemical can be recommended as a practice in strawberry culture.