Micropropagation of a Cold Hardy Selection of Cercis canadensis L. Through Single-Node Culture

Abstract

Abstract A cold hardy eastern redbud (Cercis canadensis L., TS 0092) was propagated using single-node micropropagation. In vitro shoot cultures were initiated from rapidly growing shoot tips of a mature tree. The effects of basal media and plant growth regulators on proliferation were investigated. Maximum proliferation rate was obtained from all three tested media, Murashige and Skoog (MS), Woody Plant Medium (WPM), and Driver-Kuniyuki walnut (DKW), supplemented with 0.5 μM thidiazuron (TDZ). Shoots produced on WPM medium appeared stressed showing yellowish and thin leaves compared to those on MS and DKW media. Shoots were in vitro rooted in auxin-free half strength WPM medium after being pulsed for 1 to 16 days in half strength WPM medium with 12.5 to 100 μM indole-3-butyric acid (IBA). In vitro rooting rate was influenced by IBA concentration, pulsing time, and shoot sources (media in which shoots were produced). Shoots produced in DKW medium rooted best after being pulsed in 25 to 100 μM IBA for 8 days although root numbers were similar among treatments. Direct ex vitro rooting was achieved by quick-dipping the microshoots in 10 μM IBA or NAA solutions and inserting them in Jiffy Mix potting medium.