The effect on the yield of potatoes of incorporating 2,4-d in the regular spray

Summary

• 1. Potatoes treated with as much as .875 pound of 2,4-D acid equivalent per acre as sodium salt did not break down in storage.

• 2. These potatoes, when used for seed, were not affected by the former treatment. Seed growers are warned not to use 2,4-D since the reaction on the plant might be confused with disease.

• 3. Amounts as high as 2.1 pounds of acid equivalent may be made in single applications without depressing the yield of Katahdin potatoes.

• 4. Present data do not indicate that 2,4-D treatment will consistently increase the set of tubers on muck soil.

• 5. When making single applications, the size of the plant when treatment is made does not affect the yield.

• 6. 2,4-D is compatible with some of the common fungicides used in potato spraying, i. e. Basic Copper, Bordeaux mixture, Parzate, Zerlate and Dithane D-14.

• 7. Decrease in yield of the potato crop resulted when two sprays were applied at 5-day intervals, the Russet Rural variety being affected more severely than other varieties.

• 8. Visible changes in skin color result from a spray treatment of .52 pound of 2,4-D acid. Skin color in Triumph was intensified.