ABSORPTION AND TRANSLOCATION OF HERBICIDES BY THOMPSON SEEDLESS (SULTANINA) CRAPE, <i>VITIS VINIFERA</i> L.

Abstract

Summary. Absorption and translocation of 14 C‐labelled herbicides applied in culture solutions lo the roots and in concentrated drops to mature leaves of ‘Thompson Seedless’ (Sultanina) cuttings were studied. Neither 2,4‐D nor paraquat, and only traces of 2,4,5‐T translocated from the roots to the shoot. Dicamba, amitrole, diuron, monuron, simazine and atrazine readily moved from the roots to the shoots. The substituted ureas and s ‐triazines were mobile only in the xylem or cell walls (apoplast), while dicamba and amitrole were mobile in the apoplast and symplast (living protoplasm). Both 2,4‐D and 2,4,5‐T moved almost entirely in the symplast. Paraquat moved only slightly in either apoplast or symplast. Stability of the herbicides in the plants varied, as judged by the detection of label in ethanol‐insoluble products. Dicamba was considerably more stable than 2,4,5‐T which, in turn, was more stable than 2,4‐D. Diuron was more stable than either atrazine or simazine. Amitrole largely was converted into ethanol‐insoluble products in 30 days. Paraquat was not extractable with ethanol. Absorption et migration d'herbicides chez une vigne: Thompson Seedless (Sultanina), Vitis vinifera L.