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The homozygous T-DNA mutant of the AMY1 gene in Arabidopsis was identified and importantly, shown to cause an early flowering phenotype. We found that the disruption of AMY1 enhanced expression of CO and FT. The expression analyses of genes related to starch metabolism revealed that expression of the AGPase small subunit APS1 in the wild type was higher than in the amy1 mutant. However, there were no significant differences in expression levels of the AGPase large subunit genes ApL1, AMY2, or AMY3 between wild type and the amy1 mutant. Expression profiling showed that AMY1 was highly expressed in leaves, stems, and flowers, and expressed less in leafstalks and roots. Furthermore, the level of AMY1 mRNA was highly elevated with age and in senescing leaves. RT-PCR analyses showed that the expression of AMY1 was induced by heat shock, GA, and ABA, while salt stress had no apparent effect on its expression.

A lignin and cellulose-degrading fungal strain Bio-1 was isolated from the soil of Yuelu Mountain in China. It was identified as a member of the genus Cladosporium by 18s rDNA, ITS sequences analysis and morphological characters. Bio-1 could hydrolyze at least 35% of the alkaline lignin in 4 days when incubated in screening liquid medium. Both laccase and cellulase activities could be detected in the fermentation liquid and cell homogenate. High extracellular and intracellular laccase activities of 3800 and 5352 U/L were obtained with copper induction, respectively. The extracellular cellulase production was reached (51 U/Ml). Based on these characteristics, Bio-1 could be well suited as a commercial fungus applied in degradation of lignocellulose biomass for environment protection. Key words: Cladosporium, identification, laccase, cellulase, CuSO4.

In this study, we reported the establishment of a simple protocol for the micropropagation and acclimatization of Lonicera japonica Thunb. Branches with dormant buds were collected from mature L. japonica and sprouted in a greenhouse. Tip and node segments were used as starting material for in vitro proliferation in woody plant medium (WPM). In the first assay in which explants from five different species of Lonicera were used, 95.0% of the tip segments produced new axillary shoots, thus proving to be the best explant type. Afterwards, material from L. japonica Thunb. was used to test for plant growth regulator (PGR) combination. Shoots from L. japonica were used to assay in vitro rooting using six different WPM media. Rooting percentages were high for all media and varied between 83 and 95%. For acclimatization, two approaches were assayed: the use of previously rootedin vitro plants and the direct acclimatization of shoots. After five weeks, 95.0% of the in vitrorooted plants were successfully acclimatized and 88.7%, was attained by direct acclimatization of shoots with two years shoot immersed in GA3 solution. These results proved that there is no need for a previous in vitro rooting step and that direct acclimatization can effectively reduce time and costs. Thus, the micropropagation and acclimatization of L. japonica can be divided into only two steps: proliferation of shoots in WPM and direct acclimatization of these shoots in a sterile soil mixture, or direct acclimatization of two years shoot immersed in GA3 solution for 8 h. Key words: Lonicera japonica Thunb., node segment culture, micropropagation, direct acclimatization.

This paper examined eight additional parameters relating to photosynthetic rate of Lonicera japonica Thunb. Correlation analysis, regression analysis and factor analysis were used to analyze the relationship between net photosynthetic rate (Pn) and environment factors, which included stomatal conductance (Sc), intercellular CO2 concentration (Ci), transpiration rate (Tr), air temperature (Ta), leaf temperature (Tl), air CO2 concentration (Ca), relative air humidity (RH), photo flux density (PFD), etc.. The results showed that the diurnal Pn of L. japonica Thunb. It may vary with double peak curves; there was no significant midday depression from June to August. The stepwise regression analysis which introduced characters into a multiple regression equation in the order in which they contribute to Pn, together with factor analysis was used to analyze the same dependence structure. The 8 causes were grouped into the basic factors which generate the dependence structure. The result suggested that high photo flux density (PFD), high Tl and low RH may result in the high Pn. Increasing Tr and PFD, accelerating the hot air flow, would be the most effective way of increasing Pn. The analysis result would assist the medicinal herb grower by adjusting environment factors level to regulate Pn of L. japonica Thunb. and improve output and quality of flower. Key words: Lonicera japonica Thunb., environment factors, net photosynthetic rate, interrelationships.