Flavanols, as Plant Growth Inhibitors from Roots of Peach, Prunus persica Batsh. cv. ‘Hakuto ’

Abstract

Three flavanols, which inhibit root growth in the rice seedling test, have been purified. One was (+)-afzelechin (1) and the other two, named Pia and PIb, were new biflavanols shown by the structures 2 and 3 on the basis of chemical and spectroscopic evidence. PIa inhibited the root growth of the peach seedlings. In addition, PIa was found in the soil in the area where the peach trees were growing. The flavanols, therefore, are suggested to be one of the chemical factors causing soil sickness often encountered in peach cultivation.