Profile of Absolute Light Utilization Efficiency Within Leaves of Euonymus japonicus

Absolute light utilization efficiency across leaf section of Euonymus japonicus T. was calculated based on the measurements of photoacoustic technique (PA technique) and microscopic fiber optic probe. This new method was based on the principal of depth analysis by PA technique and the differential analysis of light gradients across leaf section by micro-optical probe technique. The depth analysis was shown by a sample of PA scan light absorption spectra. Results showed that the tissue layers between palisade tissue and spongy tissue used the smallest proportion of incident light energy for photochemical reactions (about 0.026% incident light energy of 660 nm light), while in tissue layer more close to the adaxial surface of leaf or the abaxial surface of leaf, the efficiency of utilization of light energy tended to be improved, e. g. 0.092% for tissue layers close to adaxial surface; 0.036% for tissue layers close to abaxial surface. The results that different leaf tissue layers utilized different proportion of incident light energy for photochemical reaction directly prove the hypothesis put forward by Han and Vogelmann.

Study on Phenological Character in Seedling Period of Introduced Populus deltoids Clones

In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource evaluation was carried out; 8 phenological phases in seedling period were observed and analyzed of 60 Populus deltoids clones introduced from America. The results showed that： （1） there was obvious difference in phonological character among clones, especially in leaf-spread- ing peak stage and the end term of leaf-falling stage, with the largest variation co- efficient of 14.97% and the minimum of 3.83% respectively. （2） Leaf-spreading peak stage scattered but the end term of leaf-falling stage concentrated the most. The phonological character in early stage of seedling growth was the main factor influ- encing the length of growing season. （3） By principal component analysis, pheno- logical phases were classified into 3 typical periods, including germination stage, leaf-spreading peak stage and leaf-falling stage. （4） Totaling 60 clones were classi- fied into 4 types by using clustering analysis in phenological time variables of clones.

Function and Chromosomal Localization of Differentially Expressed Genes Induced by Marssonina brunnea f.sp.multigermtubi in Populus deltoides

A total of 1,160 differentially expressed genes induced by Marssonina brunnea f. sp. muhigermtubi were identified in Populus deltoides cv. ＇Lux＇ （1-69/55） with two-colour cDNA microarray including 2,952 cDNAs from two cDNA libraries constructed with 72 h inoculated poplar leaves. Functional analysis showed that 1,160 genes were classified into 11 functional categories that are involved in metabolism （15.9%）, signal transduction （9.5%）, transcription and replication （8.7%）, and cell rescue and defense （7.8%）. Among them, 926 genes were sporadically localized on 19 linkage groups. Chromosome 2 contained 102 （11%） differentially expressed genes, followed by chromosome 1 which contains 93 genes （10%）, and chromosome 17 had the least number of differentially expressed genes. Clustering of expressed sequence tags （ESTs） in poplar genome was observed at the terminal regions of several chromosomes. The relationship between cluster of genes and plant defense response would be further studied.

Development of two microsatellite multiplex PCR systems for high throughput genotyping in Populus euphratica

Eighteen microsatellite primer pairs previously developed at Oak Ridge National Laboratory for Populus tremuloides Michx. and Populus trichocarpa Torr. & Gray were screened for amplification in Euphrates poplar, Populus euphratica Oliv. Thirteen loci were found to express polymorphisms ranging from two to 17 alleles. The eight most variable loci were selected to set up and optimize two multiplex polymerase chain reaction (PCR) assays. Three populations containing altogether 436 trees were used to characterize the selected loci and ascertain their applicability for parentage analysis and genotyping studies. Through cross-checking of clonal identity against sex of the genotyped trees we estimated the maximum error rate for merging genotypes to be less than 0.045.

Simultaneous Determination of Six UV-Filters in Cosmetics by HPLC

A reversed-phase high performance liquid chromatographic method with diode-array detector was established to simultaneously determine the six UV-filters, isopentyl-4-methoxycinnamate, ethylhexyl methoxycinnamate, ethylhexyl salicylate, homosalate, butyloctyl salicylate and ethylhexyl triazone. They were separated on a Kromasil C18 column, with gradient elution by methanol and water, and detected by HPLC-DAD.All results demonstrated good linear relationship in proper mass concentration range. The limits of quantitation(LOQ) were between 0.5 and 1.25 mg/L. The recoveries of the six compounds ranged from 98.3% to 101.0% at two inrements with the relative standard deviation(RSD) no more than 1.5%.