SYMPLASTIC TRANSPORT OF GIBBERELLINS - EVIDENCE FROM FLUX AND INHIBITOR STUDIES

The pathway of transport of gibberellins (GA1 and GA3) in oat [Avena sativa cv. Victory] coleoptiles was investigated using conventional but modified transport methods and evidence from flux studies. Longitudinal transport, which is non-polar, is strongly reduced by azide. Azide does not reduce uptake of gibberellin. After a time lag of 160 min, azide increases uptake and loss of gibberellins. If transport of GA were apoplastic, it should be unaffected or even increased by the presence of azide. Therefore the hypothesis that gibberellin transport is symplastic was supported. Some part of the symplast, possibly the plasmodesmata, is affected by azide.