Persistence Of Trifluralin Research Articles

Trifluralin Persistence as Affected by Depth of Soil Incorporation

Bioassay and chemical analyses of residual α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) from greenhouse and field experiments indicated that the persistence of this herbicide is increased by deep incorporation as compared to shallow incorporation or surface application. Laboratory studies using a charcoal vapor trap indicated that trifluralin volatilization decreased with increasing depth of incorporation. Volatilization appears to be an important mode of trifluralin dissipation from the soil.

Inhibition of Cotton and Soybean Roots from Incorporated Trifluralin and Persistence in Soil

Inhibition of cotton (Gossypium hirsutum L.) and soybean (Glycine max (L.) Merr.) lateral roots by alpha, alpha, alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) was directly related to depth and method of incorporation. Root inhibition of the crop plants was reduced when trifluralin was incorporated shallowly after planting with either a power tiller or a ground-driven tiller, to a depth no greater than 0.5 in above seed placement. A bioassay of the soil showed that disking trifluralin-treated plots before bedding caused the greatest retention of the material 3 weeks later, and that retention was less when the herbicide was applied and shallowly incorporated after planting. Further studies on the relationship of soil persistence of trifluralin to depth of incorporation 6 months after application, showed no herbicide present in plots not incorporated while only minimal residues were found where incorporation was no deeper than 1 in. Residues in plots incorporated below the 2-in depth were moderate at 0.5 to 1 lb/A rates and high at the 2 lb/A rate and above.