Germination and Growth Inhibitors from Red Kidney Bean Seed

Abstract

Using the primary root growth of wheat and flax and the germination of flax as indicators, the Red Kidney bean (Phaseolus vulgaris) was found to contain water-extractable inhibitors insoluble in organic solvents. In effects on germination, the whole-bean extract was more inhibitory than prepns. from either isolated seed coats or cotyledons; this extract became more active after a brief exposure to bright sunlight. The whole-bean extract was most active in the inhibition of flax root growth, more so after illumination. The inhibitory activity of the cotyledon extract on the (lax root was decreased by illumination. The inhibiting action of the seed coat extract on the wheat root was increased slightly by illumination of this extract but removed by boiling the soln. for a few minutes. Neither u.-v. nor infra-red radiation could replace sunlight. It is suggested that more than one inhibitor or inhibiting system is present; the auxin-like action of certain extracts is pointed out.