Ethylene and in vitro rooting of rose shoots

Abstract

Effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), ethylene biosynthesis inhibitor, (CoCl2), and inhibitor of ethylene binding to receptors, 1-methylcyclopropene (1-MCP), on ethylene production and rooting in shoot culture of Rosa hybrida L. cv. Alba meidiland were studied. Additionally, effect of ethylene removal by KMnO4 and HgClO4 on rooting was tested. ACC increased ethylene production and delayed root formation, decreased the number of roots per shoot and inhibited root growth. In contrast, inhibition of ethylene production by CoCl2 accelerated root emergence, and increased the number of roots per shoot. Likewise, removing ethylene from the ambient atmosphere improved root emergence and, increased root number of per shoot and markedly inhibited root growth. Blocking the ethylene receptors by 1-MCP increased ethylene level in the ambient atmosphere and increased both emergence and root formation. Both ethylene biosynthesis and action are involved in the control of rooting. Ethylene concentration in glass jars was too high for root emergence and formation, but was appropriate for root growth. CoCl2 or 1-MPC can be recommended for regulation of rooting in rose shoot culture, since both emergence and number of roots were improved but root growth was not inhibited.