Involvement of Jasmonic Acid and Related Compounds in the Tuberization of Jerusalem Artichoke Plants(Helianthus tuberosus L.).

Abstract

Using a bioassay for tuber-inducing activity, which was carried out with cultures of single-node segments of potato stems in vitro, jasmonic acid (JA) was isolated from the leaves of Jerusalem artichoke (Helianthus tuberosus L.), and identified by both HPLC and mass spectrometry. The level of endogenous JA in the leaves of young plants was very high (4.0×10-6gt; mol·kg<-1) but decreased sharply with the growth of the plants. By contrast, the level of water-soluble derivatives of JA increased with the growth of plants and reached a maximum near the time at which tuberization was initiated. The effect of exogenous JA on the tuberization of Jerusalem artichoke plants was examined in vitro, and JA was found to have strong tuber-inducing activity. These results suggest that tuberization of Jerusalem artichoke plants is controlled by JA and related compounds.