Some aspects of the absorption of picloram by gorse (Ulex europaeus L.)

Plants of Ulex europaeus were grown from cuttings and studies made of the absorption of 14C-picloram applied with unlabelled 2,4,5-T. In vivo experiments in a growth chamber showed that absorption ceased after 10 h, but was resumed on wetting. In in vitro experiments the Q10 and the activation energy for uptake decreased with increasing temperature. Absorption was increased by addition of non-ionic surfactants, by lowering the pH and by removal of cuticular wax. Gorse shoots were shown to have a high wax content but scanning electron microscopy revealed no obvious wax structures and the contact angle of spray droplets was less than 900, indicating that the surfaces were not difficult to wet.     

Evolution des techniques d'application antiparasitaire fongicide au cours de la décennie écoulée

L'auteur souligne, dans un premier temps, l'évolution des traitements antiparasitaires vers les techniques d'épandage à bas volume. Après avoir précisé l'intérêt de ces dernières, il retrace l'historique des matériels qui ont été successivement mis au point puis énonce les diverses cultures auxquelles ils s'appliquent en mentionnant les expérimentations effectuées depuis dix ans.