Promotion of Germination of Dormant Weed Seeds by Substituted Phthalimides and Gibberellic Acid

Both gibberellic acid and the substituted phthalimide AC-94377 [1-(3-chlorophthalimido)cyclohexanecarboximide] actively promoted germination of dormant seeds in five species out of nine. The species that responded to both compounds included wild oat ( Avena fatua L.), wild mustard [ Brassica kaber (DC.) L.C. Wheeler], curly dock ( Rumex crispus L.), field pennycress ( Thlapsi arvense L.) and tansy phacelia ( Phacelia tanacetifolia L. Benth.). on a weight-per-weight basis, the ability of AC-94377 to stimulate germination was equal to, or greater than, GA 3 . The other two substituted phthalimides tested, AC-92803 [2-(3-chlorophthalimido)-2-methyl-2-isobutyl-acetamide] and AC-99524 [1-tetrahydrophthalimido-cyclohexane-carboximide], had either slight or no stimulatory activity.