Effect of Pesticides on the Yield of Some Vegetable Crops in the Isabela Area of Puerto Rico

Abstract

The effects of different pesticides, namely, Parathion, DDT, Guthion, Di-Syston, and Dylox on the yield and quality of vegetable crops, were studied in the Isabela Area. The following major results were obtained: 1. Cucumbers: Sprays with Parathion or Guthion had no effect on the yield and number of fruits produced. 2. Snap beans: DDT application at the rate of 2 pounds per acre gave a significant increase in yield. Guthion, sprayed at the rate of 6 pounds per acre per spray, also produced a significant increase in the yield. 3. Sweet corn: DDT applications at the rate of 4 pounds per acre, sprayed on weekly, controlled foliage injury and, consequently, healthier and more vigorous plants were obtained. Foliar sprays of DDT, at the same rate as above, increased the number of ears produced. Spraying the silks with DDT at the rate of 4 pounds per acre per application, or dusting them with Dylox granular, 1 pound per acre, improved the quality of the ears produced. 4. Tomatoes: Foliar sprays with DDT and Parathion did not cause a significant increase in yield nor in the number of marketable fruits produced. Granular Di-Syston at the rate of 10 pounds per acre, had no effect on the yield or number of marketable fruits in this experiment.