Gibberellins in mature apple seeds — contaminants?

Abstract
Evidence is presented that gibberellins A4 and A7, previously identified (Sinska, I., Lewak, St., Gaskin, P., MacMillan, J., Planta 114, 359–364, 1973) in extracts of mature apple (Pyrus malus L.) seeds, were present primarily as contaminants. The facts supporting this conclusion are: a) the ratio of GA4 to GA7 was similar to that of a standard mixture; b) the concentrations were extremely high; and c) the ratio of GA4 to GA7 did not change during stratification, as had been reported when extracts were bioassayed (Sinska, I., and Lewak, St., Physiol. Vég. 8, 661–667, 1970).