A cDNA clone encoding a putative EBF-like protein (DCEBF1)was obtained from total RNA isolated from senescing carnation (Dianthus caryophyllus L.) petals using reverse transcription PCR and rapid-amplification of cDNA ends techniques. The cDNA contained an open reading frame of l 878 bp corresponding to 625 amino acids. Results of Northern blot indicated DCEBFI expression was enhanced by endogenous and exogenous ethylene, and was inhibited by STS in petals and ovaries. Upon wounding treatment, DCEBF1 showed a quick increase in mRNA accumulation which was positively correlated with the increase in ethylene production. The levels of DCEBF1 mRNA increased in both petals and ovaries by sucrose treatment compared with the control.
FU Zhao-diWANG Hui-nanLIU Juan-xuZENG Hong-xueZHANG JiaoKUANG Xiao-congYU Yi-xun
This research aims at developing a plant regeneration system from leaf and petiole explants of Anthurium andraeanum Hort., thereby establish a foundation for mass production and transformation. Using tissue culture technique, the conditions for callus induction, protocorm-like body (PLB) formation and plant regeneration from leaf explants and petiole of A. andraeanum, such as basal medium and plant growth regulator, were investigated. Totipotent callus was induced on a 1/2-strength MS medium containing 0.90 μmol L^-1 2,4-dichlorophenoxyacetic acid (2,4-D) and 8.88μmol L^-1 N6-benzyladenine (BA). The callus exhibited complete hormone autonomy for growth and differentiation of PLBs. This callus proliferated well and was maintained by subculturing on 1/2 MS medium containing 0.90 μmol L^-1 2,4-D and 4.44 μmol L^-1 BA. On average, 8 protocorm-like bodies could be obtained from a piece of 4 mm callus after being transferred to the 1/2 MS medium with 4.44 μmol L^-1 BA after 8 wk of culture. The regenerated PLBs formed shoots and roots on 1/2 MS medium. After 24 wk of culture on these medium, well-developed plantlets for potting were produced. An efficient micropropagation method was established for indirect PLB formation and plant regeneration from leaf and petiole ofA. andraeanum.