No abstract

No abstract

No abstract

The preparation of new esters of o-coumaric and cinnamic acids is described. Spray applications of o-coumaric acid were inactive in vivo against Venturia inaequalis on immature leaves but alkyl esters of the acid penetrated intact leaves more readily and reduced the incidence of disease. Isobutyl o-coumarate was the most active compound. In contrast to o-coumaric acid, cinnamic acid gave some measure of control but esters of this acid were not consistently better. The most satisfactory formulation mixture for these materials contained acetone, Tween 80 and Triton X-100, giving a fine crystalline suspension.Systemic action of isobutyl o-coumarate in shoots of the apple variety Cox's Orange Pippin was demonstrated, and its presence in the upper epidermis of the first five leaves above those to which it had been applied was shown by thin-layer chromatography of extracted material.

No abstract