The elongation of pea stem sections brought about by indoleacetic acid (IAA) and gibberellic acid (GA3) can be increased considerably by trace quantities of a large number of fatty acid esters and chemically related compounds (19,21). The emulsifying teclhnique used for these alkyl lipids has permitted the studv of the effect of some natural oils and of fatsoluble vitamins on pea stem section growth for the first time. In this paper it is shown that vitamins K, and E, and some related isoprenoid compounds, are like the alkyl lipids studied earlier in that they stimiiulate pea section growth in a similar manner adI (l0o so at even lower concentrations. No simple theor-y has yet been found adequate to explain this effect, but the results are compatible with the earlier suggestion (20,23)

No abstract