EFFECT OF GIBBERELLIC ACID ON SEVERAL OFFICIAL DRUG PLANTS

Summary

Contrary to general concepts, gibberellic acid solution by single foliar spray does not induce the typical „gibberellin effects” on several drug plants. Refractive to a single treatment were found in this study Ricinus communis, Pimpinella anisum, Foeniculum vulgäre, Coriandrum sativum, Sesamum indicum, Plantago spp, Linum usitatissinum, Salvia officinalis, Thymus vulgaris, Lavandula officinalis, and Carthamus tinctorius.

The responses of two umbelliferous plants, fennel and coriander under controlled greenhouse conditions are reported in detail. These plants which were refractive to single treatment received foliar sprays of 100 p.p.m. G.A. twice weekly, eliciting a difference of cauline length of 200–300 %. No significant differences were found with respect to yield of fruits, the quality and quantity of volatile oils. The same information has been given for Ricinus communis.

In seed germination experiments, great inter– and intra–genus variability of response has been noted.

Since the mode of action of gibberellic acid is presently not completely understood, except that it differs in several respects from that of the auxins, might it be that the failure of response of several tested plants is due to a varying natural content of gibberellin or gibberellin–like substances, so that higher external quantities are needed for conventional response?

Zusammenfassung

Es wird die Reaktion einiger Arzneipflanzenarten auf zweimal wöchentliches Besprühen mit Gibberellinsäure beschrieben.