EFFLUX OF DICHLOBENIL FROM SHOOTS AND ROOTS OF CORN

The root uptake, distribution, and vapor loss of 2,6-dichlorobenzonitrile-7 14C(dichlobenil) in corn (Zea mays) seedlings were determined by assay of plant extracts and vapor trapping solutions. When the concentration of 14C-dichlobenil in the nutrient solution was maintained at approximately 0.3 p.p.m., the maximum quantity in the corn roots was attained after 12 hours and the quantity in the shoots continued to increase up to 72 hours. Unaltered 14Cdichlobenil vapor was emitted from the shoots of preloaded corn plants similarly in the light and dark, but the efflux was temperature dependent. The quantity of herbicide emitted from plants in 24 hours was 70 to 80% of the amount absorbed. Root loss was sevenfold the amount lost from shoots over a similar 24-hour trapping period at 27° C. © 1969, American Chemical Society. All rights reserved.