Relationship Between Trifluralin and Phosphorus on Transplanted Tomatoes

Abstract

Tomato (Lycopersicon esculentumMill. ‘Campbell 17’) plant height and dry weight of tops decreased with increasing rates of α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) and increased with increasing rates of phosphorus. Trifluralin and phosphorus interacted in their effects on root growth; phosphorus was less effective in promoting root growth as the rate of trifluralin increased. Phosphorus content of plant tops increased with each increment of soil-applied phosphorus at 0 and 0.84 kg/ha of trifluralin, but each increment of applied phosphorus did not significantly increase plant phosphorus content at higher rates of trifluralin. The inhibitory effect of trifluralin on phosphorus uptake diminished with time in 1969. Interactions between trifluralin and phosphorus did not occur in 1970.