Relation of Phosphorus Nutrition to the Translocation of 2,4-Dichlorophenoxyacetic Acid in Tomato Plants

Abstract

It has frequently been observed that the effectiveness of such herbicides as 2,4-dichlorophenoxyacetic aeid (2,4-D) Immediately after measuring the curvatures, the 10 plants in each series which had received the C14-labeled 2,4-D were harvested. The roots of these plants were washed free from the sand in which they were growing and any unabsorbed 2,4-D was washed off the treated leaves with a small stream of 70 % ethanol followed by distilled water. The treated leaf was then severed from the rest of the plant at the

Transport in the Phloem

“…A number of papers take up this subject. It has been shown for potassium and phosphorus that a nutritional deficiency may be a limiting factor (97,99). Temperature, formulation, the use of surfactants, place of application, etc., are other im portant factors (2,20,52,70,127).…”

Relation of Potassium Nutrition to the Translocation of 2,4-Dichlorophenoxyacetic Acid in Tomato Plants.

“…Scott (9) found that application of potassium to potassium-deficient morning glory and zinnia plants three days before treatment with 2,4-D resulted in a significant decrease in elongation of the main axis as compared with similarly treated plants given potassium at the time of application of 2,4-D. More The radioautograms (fig 1) indicated that a considerable amount of radioactive material moved through the stems, hypocotyls, and even into the roots of most of the plants which were given potassium three days before the labeled 2,4-D was applied to them. The movement of radioactive material was considerably greater in those plants which received potassium 8 hours before application of the 2,4-D-1-C14 than in those which received the potassium later but was less than in those plants which received the potassium three days before. Six of the plants which received potassium 8 hours before application of the 2,4-D had radioactive material in the roots, whereas no plants which received potassium later exhibited this condition.…”

“…has been shown to have a marked effect on the translocation of this plant growth regulator (8). Scott (9) found that application of potassium to potassium-deficient morning glory and zinnia plants three days before treatment with 2,4-D resulted in a significant decrease in elongation of the main axis as compared with similarly treated plants given potassium at the time of application of 2,4-D. More The radioautograms (fig 1) indicated that a considerable amount of radioactive material moved through the stems, hypocotyls, and even into the roots of most of the plants which were given potassium three days before the labeled 2,4-D was applied to them.…”

Effect of nitrogen and phosphorus status on the translocation of three herbicides in field bindweed (Convolvulus arvensis L.)

“…Rohrbaugh and Rice [23] found less stem curvature and accumulation of ~4C-2,4-D in roots of tomato (Lycopersicon esculentum Mill.) plants deficient in P than in plants grown with adequate P. Baird et al [1] reported that application of N to quackgrass (Agropyron repens L.) 30 days prior to treatment with glyphosate significantly improved control, which was attributed to greater herbicide translocation resulting from increased vegetative growth.…”