Cloning of cDNA Encoding COMT from Chinese White Poplar ( Populus tomentosa ), Sequence Analysis and Specific Expression

The cDNA fragment encoding caffeic acid 3_O_methyltransferase (COMT) in Chinese white poplar ( Populus tomentosa Carr.) was isolated and cloned by RT_PCR technique. The size of the cDNA fragment is 1 080 bp, which almost covers the whole cDNA_encoding region. Authors’ cDNA fragment in P. tomentosa shares 98.7% homology with the reported corresponding cDNA in the P. tremuloids at nucleotide level, 99.4% homology at amino acid level, respectively. The analysis of Northern dot hybridization showed that COMT is expressed specifically in the developing secondary xylem of stem during the season of xylem differentiation, which means the linkage between the gene expression for a monolignol biosynthetic enzyme and seasonal regulation of xylem development in woody plant.

Discussion on Feasibility of Adjustment Program for Jiangmen Chinese White Dolphin Provincial Nature Reserve

From the protection of Chinese white dolphin and living environment,and considering the industrial development in coastal areas,we put forward adjustment program for Jiangmen Chinese White Dolphin Provincial Nature Reserve. Meanwhile we analyzed the feasibility of this program by systematically focusing the effect of adjusted functional regions on Chinese white dolphin.

Transcriptomic and proteomic analyses on the supercooling ability and mining of antifreeze proteins of the Chinese white wax scale insect

The Chinese white wax scale insect, Ericerus pela, can survive at extremely low temperatures, and some overwintering individuals exhibit supercooling at tempera- tures below -30℃. To investigate the deep supercooling ability ofE. pela, transcriptomic and proteomic analyses were performed to delineate the major gene and protein families responsible for the deep supercooling ability of overwintering females. Gene Ontology （GO） classification and Kyoto Encyclopedia of Genes and Genomes （KEGG） analysis indicated that genes involved in the mitogen-activated protein kinase, calcium, and PI3K-Akt signaling pathways and pathways associated with the biosynthesis of soluble sugars, sugar alcohols and free amino acids were dominant. Proteins responsible for low-temperature stress, such as cold acclimation proteins, glycerol biosynthesis-related enzymes and heat shock proteins （HSPs） were identified. However, no antifreeze proteins （AFPs） were identified through sequence similarity search methods. A random forest approach identified 388 putative AFPs in the proteome. The AFP gene ep-afp was expressed in Escherichia coli, and the expressed protein exhibited a thermal hysteresis activity of 0.97℃, suggesting its potential role in the deep supercooling ability ofE. pela.

Segregation of AFLP Markers in A ( Populus tomentosa× P. bolleana) ×P. tomentosa Carr. BC_1 Family

To investigate the levels of polymorphisms and Mendelian segregation ratio in clone “TB01” (P. tomentosa×P. bolleana) ×clone “LM50” (P. tomentosa) BC 1 population at the entire genome level, amplified fragment length polymorphisms (AFLPs) analysis was conducted for both parents and 120 progenies. Forty one pairs of selective primers were used to detect 2?707 bands, of which 712 (26.4%) were polymorphic. Chi\|square tests were performed to examine if the observed genotypic frequencies of AFLP loci deviated from expected 1∶1 Mendelian segregation ratio ( P <0.01) in BC 1 population. Among the 712 loci 571 (80.2%) fit to Mendelian 1∶1 segregation ratio, corresponding to DNA polymorphisms heterozygous in one parent and a null in the other. The result shows that the AFLP markers are very suitable for fingerprinting and genetic mapping in the Chinese white poplar (Populus tomentosa Carr.).

New Varieties of Populus tomentosa Carr. and Breeding Techniques

The main morphological characteristics, producing area and growth characteristics of sixteen new varieties of Chinese white poplar （Populus tomentosa Carr. ） are reported, aiming at providing reference for breeding and extension of new varieties.