Plant Growth Regulation

, Volume 9, Issue 2, pp 119–125 | Cite as

Retardation of abscission of citrus leaf and fruitlet explants by brassinolide

  • Shuichi Iwahori
  • Shigeto Tominaga
  • Shinichi Higuchi


Brassinolide (BR), a novel plant growth-regulating steroidal lactone, markedly retarded the abscission of leaf explants of Calamondin (Citrus madurensis Lour.), when dissolved in water and fed through the petiole. BR was effective at concentrations as low as 0.021 μM, and showed a stronger effect than IAA which also retarded abscission. Trifluoperazine (TFP), an inhibitor of the calmodulin-calcium complex, accelerated abscission, and this acceleration could be counteracted by a simultaneous addition of IAA or BR, the effect of IAA being stronger. BR in lanolin applied to the cut surface of the leaf blade of the explant showed a weaker abscission-retarding effect than that applied in water via the petiole. BR and IAA also markedly retarded the abscission of fruitlet explants of Calamondin.

Key words

abscission brassinolide Calamondin Citrus madurensis IAA trifluoperazine 


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Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • Shuichi Iwahori
    • 1
  • Shigeto Tominaga
    • 1
  • Shinichi Higuchi
    • 1
  1. 1.Facutly of AgricultureKagoshima UniversityKagoshimaJapan

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