Einfluß von Pasten mit verschiedenen Indolylessigsäure-Konzentrationen auf den Transport von 32P in dekapitierten Erbsenepikotylen

Abstract

Either a 0.25% or a 0.007% IAA paste was smeared on the apical cut surface of decapitated pea epicotyls and simultaneously ³²P was added to the roots. When subsequently the radioactivity of the apical segment of the epicotyls was measured at different time intervals following the addition of ³²P, no significant differences between the effect of 0.25 and 0.007% IAA paste on ³²P transport were found. Because the 0.25% IAA paste completely retards the growth of cotylary buds whereas the 0.007% paste supports this growth, it might appear that the effect of 0.25% IAA paste on the transport of nutrient substances plays a decisive role in the apical dominance. More probably 0.25% IAA paste imitates the apical dominance only by means of its toxic effect, which, however, requires a detailed investigation.