An inhibitor of indoleacetic acid oxidase from pea tips

Abstract
A 3-(p-hydroxy-cinnamoyltriglucosyl) derivative of kaempferol has been isolated from plumules of etiolated pea plants treated with red light prior to harvest. This compound, which is an IAA oxidase inhibitor, is more abundant in red light treated plumules than it is in completely dark grown controls. Two flavanoid cofactors for IAA oxidase, naringenin and apigenin-7-glucoside, have also been found. It is proposed that one possible mechanism for the effects of red light on plant growth is through control of IAA oxidase cofactor-inhibitor balance.