Abstract:The soil microbial community diversity at different soil depths (0-20 cm, 20-40 cm, 40-60 cm) was analyzed by phospholipid fatty acid (PLFA) method in coniferous forest and Schima superba plantations in Heshan, Guangdong Province. The results showed that the amounts of total PLFAs, bacterial PLFAs, fungal PLFAs, Gram-positive bacterial PLFAs and Gram-negative bacterial PLFAs were the highest at 0-20 cm soil layer and decreased with increasing soil depth; the total PLFAs in Schima superba plantation was higher than that in coniferous forest, and was positively correlated with soil organic carbon and total nitrogen in the plantations. In the same soil layer, the concentration of bacterial PLFAs was higher than fungal PLFAs. Principal component analysis (PCA) indicated that the variation in soil microbial biomass and community structures were influenced by the differences of plantations and soil depth, PC1 was mainly composed of fatty acids of i13:0、a13:0、17:0、cy17:0 and 16:0, and PC2 mainly composed of i16:0、cy19:0、18:1ω9c、i15:0、18:2ω6c and a17:0.

Abstract:The effects of water supply on seed germination, seedling morphology, and biomass allocation of Quercus franchetii were studied. The results showed that water supply affected significantly the seed germination of Q. franchetii. With increment of water supply, the germination rate, germination index, germination time, and germination duration of seeds increased, but germination time lag and coefficient of germination rate decreased. All of seedlings could survive under water supply of 4-12 mm per times. However, the accruements of seedling growth and biomass accumulation rate of Q. franchetii reduced with decreasing water supply. Meantime, water supply level had significant effects on biomass allocation of seedlings. The ratio of root-to-shoot of seedlings declined substantially with increment of water supply. Under low water supply, seedlings could transport photosynthates from leaves to belowground for increasing root-to-shoot ratio.

Abstract:The forest of Picea likiangensis var. linzhiensis Cheng et L. K. Fu, widely distributed in southeast Xizang (Tibet), China, is one of the major Tibetan plateau subalpine dark coniferous forest types. Twelve sample plots in southeast Tibet were selected from the distribution center of this forest type to investigate its community characteristics, including the species composition, floristic characteristics, community physiognomy, and vertical and horizontal structure. The results showed that there were 144 vascular plants, belonging to 53 families and 116 genera, and 81.03% of the genera contain only one species. The floristic components, life-form spectrum, and leaf characters of the communities showed a typical temperate character. In vertical structure, the communities could be clearly divided into arbor layer, shrub layer, herb layer, and some interlayer plants. The canopy density of arbor layer ranged from 0.4 to 0.8, and which was dominated by individuals of Picea likiangensis var. linzhiensis. The horizontal structure was not symmetrical in the communities. The age structure of dominant population showed that the communities were steady state. The species diversity of the community is relatively low with richness index of 32.6364, Shannon-Wiener index of 3.0926, Simpson index of 0.9366, and evenness index of 0.8942. The diversity pattern was in order as herb layer > shrub layer > arbor layer.

Abstract:The damages of Hypnum fertile (Bryopsida: Musci) and its physiological responses were studied under enhanced UV-B radiation for 3 weeks. The doses of biologically effective UV-B irradiation were 6.93 kJ m-2d-1 (ambient UV-B radiation) and 9.01 kJ m-2d-1 (enhanced UV-B radiation, about 30% higher than ambient UV-B radiation), respectively. The results showed that the contents of chlorophyll and carotenoid of H. fertile both decreased with time under enhanced UV-B radiation, whereas MDA content significantly increased，and the activities of SOD, POD and CAT all increased. It is suggested that enhanced UV-B radiation caused oxidative stress to H. fertile and the oxidative stress might be alleviated by increasing the enzymes activities.

Abstract:The changes in quality and flesh color of ‘Jin Yan’ kiwifruits were investigated. ‘Jin Yan’ kiwifruits (Actinidia chinensis × A. eriantha) were harvested at four different times, and stored for 60 days at (23±1)℃ and for 2, 4, 6 months at 4℃, respectively, before maintained for 2 weeks at ambient temperatures [(23±1)℃]. The results showed that the respiratory peaks of fruits harvested at Ⅰ and Ⅳ stages were earlier than those of fruits harvested at Ⅱand Ⅲ stages, and the fruit weight loss were also faster, as well as the titratable acidity (TA), vitamin C (Vc) content and flesh firmness rapidly decreased. Fruit lightness (L*), chroma (C*) and hue angle (h) in fruits of the four harvest stages decreased significantly during ambient storage, nevertheless h changed more obviously than L* and C* in fruit maintained for 2 weeks at ambient temperature after cold storage. It suggested that the harvest Ⅱ and Ⅲ stages were suitable for harvesting of ‘Jin Yan’ kiwifruit, and h could be used as an appropriate indicator of ripening and senescence of kiwifruit. In addition, edible quality and flesh color of ‘Jin Yan’ kiwifruit were well maintained even after cold storage for 6 months.

Abstract:The relationship between pectin pethylesterase (PME) genes expression and aril breakdown of longan (Dimocarpus longan Lour.) fruit was studied by using RT-PCR and RACE-PCR methods. Three PME cDNA fragments containing 3′UTR (untranslate region), named as DlPME1, DlPME2 and DlPME3, respectively, were cloned from longan fruits. The deduced amino acid sequences of the three DlPMEs genes shared high homology with those of other plants. Moreover, their expression profiles were studied by using semiquantitative RT-PCR during aril breakdown of longan fruits. When stored at room temperature, the expression of DlPME1 gradually weakened during aril breakdown of longan fruits, while DlPME3 and DlPME2 transcripts increased progressively and then decreased. However, accumulations of DlPME1 and DlPME3 transcripts enhanced firstly, then decreased stored at low temperature (4℃), and DlPME2 transcript continuously decreased. These suggested that the expression patterns of DlPMEs were different during aril breakdown of longan fruits, DlPME2 and DlPME3 might be involved in the aril breakdown of longan fruits stored at room temperature, while DlPME1 and DlPME3 did at low temperature.

Abstract:Plant expression vectors pUBCG0229-cry1Ac with size of 8602 bp, which had anti-insect gene and the bar gene as screening marker gene, was constructed. The result of restriction digestion showed that the construction of the vectors pUBCG0229-cry1Ac was completely correct. The embryonic callus of Saccharum Complex ‘FN95-1702’ and ‘GT94-119’ were transformed with the plasmid of pUBCG0229-cry1Ac by bombardment. After selection with PPT (Phosphinothricin) or Basta, 86 regenerated plants were obtained. After detected by PCR, Dot-Southern blotting and sequencing of PCR products from 22 transformed plants, it proved that cry1Ac gene had been integrated into sugarcane genome.

Abstract:Bulbophyllum didymotropis and B. protractum are newly reported to Chinese flora. Their descriptions and photos are also provided.

Abstract:Karyotypes of 12 species of Paphiopedilum subgenus Paphiopedilum were studied by root tips squash method. The results showed that the chromosome number and karyotype were different among these species. The formulae were as follows: P. philippinense for 2n=2x=26=16m+10sm, P. dithanum for 2n=2x=26=20m+6sm, P. densissimum for 2n=2x=26=22m+4sm, P. parishii and P. hirsutissimum for 2n=2x=26=24m+2sm, P. henryanum, P. markianum and P. rhizomatosum for 2n=2x=26=26m, P. callosum for 2n=2x=32=2M+24m+6sm, P. microchilum for 2n=2x=38=28m+10sm, P. appletonianum and P. hainanensis for 2n=2x=38=30m+8sm. The diploid mainly consisted of metacentric chromosomes without satellites. The ratio of the longest chromosome to the shortest chromosome (Lc/Sc) ranged from 2.07 to 3.44. The percentage of chromosomes with arm ratio (P.C.A)＞2 ranged from 0 to 23.1%. The index of the karyotypic asymmetry (As.K) was from 53.50% to 58.95%. The karyotypes of P. henryanum, P. dithanum, P. densissimum, P. parishii, P. markianum and P. rhizomatosum were of Stebbins’s 1B type, and the others belong to 2B type.

Abstract:On the basis of field investigation, there were 62 orchid species, belonging to 33 genera in Qiyunshan Nature Reserve, Jiangxi Province, in which terrestrial were dominant with 45 species to 22 genera, and 16 species to 11 genera for epiphytic and 1 species to 1 genera for saprophytic. The endemic to China and temperate species were mainly distributed in the high altitude above 1000 m; the tropical species were mainly distributed in the low altitude below 400 m. There were 21 monotypic genera, accounting for 63.6% of total genera in the Reserve. The orchid genera in Qiyunshan Nature Reserve could be divided into 11 areal-types and 2 areal-subtypes. The East Asia distribution in species level was dominant. There are 15 species endemic to China in the Reserve. Compared with neighboring regions, Qiyunshan Nature Reserve and Jinggangshan Nature Reserve had the highest similarity coefficient with 44.0%, while it had the lowest similarity coefficient (38.2%) with Lushan.

Abstract:Nine compounds were isolated from the macroalga Gracilaria lemaneiformis (Bory) Dawson. Their structures were elucidated to be (2S)-1-O-palmitoyl-3-O-β-d-galactopyranosylglycerol (1), (2S)-1-O-palmitoyl-2-O-palmitoleoyl-3-O-β-d-galactopyranosylglycerol (2), (2S)-1-O-palmitoyl-2-O-oleoyl-3-O-β-d-galactopyranosylglycerol (3), palmitic acid (4), linoleic acid (5), uridine (6), adenosine (7), butylisobutyl phthalate (8), and 1,4-dibenzoyloxybenzene (9) on the basis of spectroscopic analysis. All these compounds were obtained from G. lemaneiformis for the first time.

Abstract:Seven compounds were obtained from the EtOH extract of the seeds of Antiaris toxicaria (Pers.) Lesch. On the basis of spectral analysis (NMR, MS, IR, etc.), their structures were identified as: periplogenin (1), antialloside (2), antiogoside (3), strophanthidin (4), strophalloside (5), strophanthojavoside (6), and desglucocheirotoxin (7). Compound 7 was isolated from the seeds of Antiaris toxicaria for the first time. All of the compounds showed significant inhibitory activities towards chronic myelogenous leukemia (K562), human gastric carcinoma (SGC-7901), and human hepatoma (SMMC-7721) cell lines.

Abstract:The influence factors of ISSR-PCR for Dracaena cambodiana Pierre ex Gagnep were studied by using single factor test and orthogonal design, and a set of ISSR-PCR reaction system was established. Sixteen ISSR primers were selected out, and their annealing temperatures were also optimized. Furthermore, the optimized reaction conditions were examined for its repeatability in D. cambodiana. The optimum ISSR-PCR reaction system with total 25 μL reaction solution contain 2.5 μL 10×PCR buffer, 3.0 mmol/L MgCl2, 300 μmol/L dNTPs, 3.0 U Taq polymerase, 0.2 μmol/L primers, and 20 ng DNA template, which can be used for analysis in genetic diversity and genetic structure of D. cambodianas.

Abstract:The advances in characteristics of EST derived SNPs in plants and development strategies were reviewed, and the preliminary results of developing EST-SNPs from Actinidia chinensis complex were introduced. The potential applications of EST-SNPs in kiwifruit population genetic studies were further discussed, and the development of EST-SNPs in other species was prospected.