Poster: Hormones

Abs # 650: Genetically engineering chrysanthemum plants Dendranthema x grandiforum to extend dark-storage life of cuttings

Presenter:	Khodakovskaya, Mariya , m_khod@yahoo.com
Authors	Khodakovskaya, Mariya  (A)   McAvoy, Richard  (A)   Li, Yi  (A)
Affiliations:	(A): University of Connecticut

To extend the storage life of whole plants or plant parts (e. g. cuttings) under dark conditions we transformed chrysanthemum plants (cv. Iridon) with a gene to increase cytokinin production under the control of a stress-inducible promoter. This promoter was selected so that gene expression would only occur after plants were exposed to a brief but specific environmental stress. Our data show that, following exposure to a 72 hours stress period, transgenic chrysanthemum leaves remained healthy and green even after 4 weeks of dark incubation at 25C. Leaves of non-transformed plants yellowed and senesced under the same storage regime. The transgenic leaves showed a significantly prolonged retention of chlorophyll. RT-PCR indicated a marked increase in gene expression between transgenic leaves exposed to a short stress treatment prior to dark storage and those that received no stress treatment.