Growth and germination inhibitors in rice husks

A search for growth and germination inhibitors in rice husk (Oryza sativa L. cv Koshihikari) revealed four compounds, ineketone, S(+)-dehydrovomifoliol, momilactone-C and p-coumaric acid, in addition to the previously known momilactones-A and -B. The isolation and structural determination of these inhibitors are reported. The flavonoid tricin and three steroids were also detected in the husk but none showed any inhibitory activity.     

Stimulation of growth and pyruvate oxidation in Streptococcus faecalis by asparagusic acid and its derivatives

Plant growth inhibitors I, II, III, VII, VIII, which occur inasparagus, promoted growth and pyruvate oxidation in Streptococcusfaecalis 10Cl. Activities were compared with those obtainedwith -lipoic acid and several structurally related syntheticsulfur containing compounds. (Received February 21, 1973; )     

Asparagusic acid, a new plant growth inhibitor in etiolated young asparagus shoots

Yellow prisms of asparagusic acid, with a molecular formulaof C₄H₆O₂S₂ were isolated from etiolated asparagus tissues (Asparagusofficinalis L.). This acid inhibits growth in lettuce and otherseedlings when applied in concentrations of 6.67x10^–7Mto 6.67xl0^–7M. The extent of activity was very similarto that of abscisic acid. ¹ A well known shift reagent in the NMR spectrum (1). (Received April 12, 1972; )     

The coumarin heraclenol as a growth inhibitor in parsley seeds

By the aid of germination assay with lettuce seeds, the germination inhibitors in the parsley seeds were investigated. One of the inhibitors was revealed to be heraclenol.