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Lilium sargentiae E.H. Wilson (Liliaceae) is an ornamental and economic flowering bulb in China. Unfortunately, due to low natural bulb multiplication rates or long juvenile phases, commercial release of a new genotype may take 10 or even 20 years. In this study, bulbs were expanded in test tubes by adding sucrose, to shorten the duration of the commercial production cycle. Results indicated that when sucrose, with a concentration of 60 g l−1, was supplied to the culture medium, the bulblets could be most effectively induced and expanded. The effect of sucrose on the formation and expansion of L. sargentiae was obvious and dominant. It was not connected to the osmotic potential of sucrose, nor entirely explained by the function of sucrose as an energy and carbon source. We used sugar analogues in the culturing of explanted materials to research the effect of sucrose-specific signaling on bulblet formation and expansion. Results showed that exogenous 3-O-methyl glucose could not induce and expand test-tube bulblets, which was similar to mannose, whereas isomaltulose could generate similar results to those obtained with sucrose. The results further indicated that the specific signalling of sucrose could be responsible for the effect on bulblets formation and swelling. We used the exclusion method to confirm above results and hypothesis, and observed that only a small part of sucrose was transformed by cell wall invertase and entered the cells through hexose transporters, playing a certain effect on bulbelt growth and development through hexose or hexose signaling systems. Overall, the effect of sucrose on bulblet induction and swelling could be explained by sucrose-specific signaling. Furthermore, this effect has a direct correlation with the sucrose-specific vector.

Due to 4f electron characteristics and alternation valence, cerium involved in an oxidation-reduction reaction in plant, closely relating to photosynthesis. Our studies proved that cerium could promote photosynthesis and greatly improve spinach growth. However, the mechanism of promoting energy transfer and conversion by cerium remains unclear. Here we reported that the effects of Ce 3+ on energy transfer and oxygen evolution in photosystem II (PS II) isolated from spinach, which was related to 4f electron characteristics and alternation valence in Ce molecule. The methods of absorption spectrum, fluorescence spectrum were used in the research. Results showed that Ce 3+ treatment at low concentration could suitably change PS II microenvironment, increase the absorbance of visible light, improve the energy transfer among amino acids within PS II protein-pigment complex, and accelerate energy transport from tyrosine residue to chlorophyll a. In summary, the photochemical activity of PS II (fluorescence quantum yield) and its oxygen evolving rate were enhanced by Ce 3+ .