Abstract:The type material of Synotis cordifolia Y. L. Chen (Asteraceae-Senecioneae) is found to match perfectly with that of Vernonia mairei H. Lév., which has long been treated as a synonym of the very variable S. erythropappa (Bureau & Franch.) C. Jeffrey & Y. L. Chen. Synotis cordifolia is therefore also reduced to the synonymy of S. erythropappa.

Abstract:In order to understand the phylogenetic relationships in genus Lycoris, the atpB-rbcL spacer regions of chloroplast DNA (cpDNA) were sequenced from selected 95 taxa, including 15 species, 4 varieties and 2 hybrids. The results showed that 95 taxa were clearly classified into two main clades from phylogenetic tree based on atpB-rbcL sequences. There were close relationship among L. radiata var. pumila, L. sprengeri, L. caldwellii, L. albiflora, L. straminea and L. houdyshelii. The interspecific relationship revealed by atpB-rbcL sequences is partially consistent with morphological and karyotype classification. The species with subtelocentric chromosome grouped Clade I, and the species with telocentric and metacentric chromosomes formed Clade II. The species with subtelocentric, telocentric and metacentric chromosomes dispersed in the two clades, it verified the hypothesis that Lycoris species with subtelocentric, telocentric and metacentric chromosomes were hybrid origin. Combining the data from two artificial hybrids, atpB-rbcL sequence analysis also revealed that subtelocentric chromosomes of L. albiflora and L. caldwellii derived from L. sprengeri, while those of L. houdyshelii and L. straminea from L. radiata var. pumila.

Abstract:In order to understand systematic relationship of Verbenaceae, chloroplast genes, such as ycf6-psbM, trnV-atpE, rbcL, trnL-F, psbM-trnD, atpB-rbcL, trnC-ycf6, trnH-psbA, rpl36-infA-rps8 and nrDNA ITS of Premna microphylla Trucz. were amplified by PCR and sequenced. Among these loci, rbcL, trnL-F and trnHpsbA were efficient for both PCR amplification and DNA sequencing, while other sequences don't conform to DNA barcode standard, ITS had no specific bands, ycf6-psbM could not sequence successfully, and the others had double peaks or high noisy values. However, rbcL is better than others according to DNA barcoding standard. The phylogenetic relationships among four genera from Verbenaceae, such as Premna L., Vitex L., Verbena L., and Clerodendrum L., and four genera from Labiatae, such as Lamium L., Stachys L., Salvia L., and Teucrium L., were studied by both combined and individual analyese using the chloroplast genes rbcL and matK sequences. The gene trees were constructed by maximum parsimony method with Lithospermum multiflorum as outgroup. It suggested that Premna L. and Clerodendrum L. were supposed to be moved to Labiatae from Verbenaceae and Verbena L. in Verbenaceae taxonomically, and the systematic position of Vitex L. was worthy of further study.

Abstract:In order to understand the response of photosynthesis and ultrastructure of mesophyll cells to drought stress, three cultivars of Jaminum sambac, including ‘Unifoliatum', ‘Bifoliatum' and ‘Trifoliatum', were cultured in pots experiment in greenhouse under different drought treatments (mild drought, moderate drought, severe drought), The effects of drought stress on photosynthetic characteristics and ultrastructure of mesophyll cells in J. sambac were studied. The results showed that the net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) and intercellular CO₂ concentration (Ci) in J. sambac ‘Unifoliatum' and ‘Trifoliatum' decreased under mild drought stress, and the ultrastructure of mesophyll cells was only slightly affected. Under moderate drought stress, Pn, Tr, Gs and Ci of ‘Unifoliatum' and ‘Trifoliatum' decreased continuously except Ci of ‘Trifoliatum' increased, while chloroplast structure changed obviously and occurred damage. Under severe drought stress, Pn, Tr and Gs of ‘Unifoliatum' and ‘Trifoliatum' had singnificant decrease compared to those of control (P<0.01), and Ci increased, while chloroplast structure changed tremendously and occurred serious damage. The Pn, Tr, Gs and Ci of ‘Bifoliatum' decreased slightly with increment of drought stress, and ultrastructure of mesophyll cells of ‘Bifoliatum' had not obvious changes. Therefore, the tolerance ability to drought of J. sambac ‘Bifoliatum' is stronger than that of ‘Unifoliatum' and ‘Trifoliatum'.

Abstract:Phreatia elegans Lindl. and Oberonia falcata King et Pantl., two new records of Orchidaceae from China, are reported. Phreatia elegans is characterized by its saccate mentum, slightly curved pedicel and ovary, clawed lip with hairy disc; Oberonia falcata resembles O. angustifolia in having well-developed stems, but differs from it by having clearly 3-lobed lip, bifid middle lobe.

Abstract:In order to understand the function of SlmiR393 in tomato (Lycopersicum esculentum), the precursor sequences and potential target genes of SlmiR393 were obtained by searching tomato genome database with computational algorithms. The SlmiR393 gene was amplified from tomato genomic DNA by PCR and integrated into plant expression vector pLP35s-100. Sly-miR393 guided-cleavage to putative target genes mRNAs was validated using 5' RACE RT-PCR. The expression of SlmiR393 and its target genes in tomato different tissues were determined by Real-time quantitative PCR. The results showed that the precursor sequence of SlmiR393 contains the complete hairpin structure. Three auxin receptor gene homologs (SlTIR1, SlTIR1-like1 and SlAFB) mRNAs contain recognition sites with high complementarities to Sly-miR393 sequence. In tomato, SlmiR393 directs the cleavage of SlTIR1, SlTIR1-like1 and SlAFB mRNA. The expression of SlmiR393 has opposite effects on SlTIR1, SlTIR1-like1 and SlAFB in stem, leaf, bud and flower, respectively. Therefore, it was suggested that SlmiR393 might direct specific target gene mRNA cleavage in tomato specific tissue and developmental stage, and the auxin receptor homologous (SlTIR1, SlTIR1-like1 and SlAFB) were validated to be as target of SlmiR393. Additionally, the pLP35s-pre-SlmiR393 vector containing SlmiR393 gene was successfully constructed with CaMV 35S as promoter, which laid a foundation for further studies of SlmiR393 function in auxin signaling pathway in tomato.

Abstract:In order to understand molecular mechanism of floral scent formation of Narcissus tazetta var. chinensis, based on a fragment cDNA from different florescence suppression subtractive hybridization (SSH), the salicylic acid carboxyl methyltransferase gene was cloned from N. tazetta var. chinensis by RACE and RTPCR, named NtSAMT1 (GenBank No. JX273470). The full length of NtSAMT1 cDNA was 1323 bp with an 1131 bp ORF, which encoded a protein of 376 amino acids with a conservative domain of methyltransf_7 superfamily. NtSAMT1 is similar to SAMT of Clarkia breweri (1m6eX) in three-dimensional structure. The NtSAMT1 is predicted an unstable protein. Phylogenetic analysis showed that SAMT in Narcissus tazetta var. chinensis had close relationship to that in Oryza sativa Japonia (BAD12867). Prokaryotic expression showed that recombinant pGEX-NtSAMT1 had highly expression in NE. coil BL21. Semi-quantitative RT-PCR revealed that NtSAMT1 could expression in all tissues of buds, the expression in stamens and pistils was the highest at first day after blooming and its expression disappeared at the eighth day after blooming. The expression of NtSAMT1 could be detected in scape, petal, corolla, stamen and pistil of the first day of blooming, expression of NtSAMT1 in the first day flowers was in order as stamen, pistil > scape > petal, corolla.

Abstract:The purpose was to investigate genetic diversity of Sargassum horneri populations in the coastal areas of Zhejiang Province, China. The 5.8S rDNA-ITS sequences from 44 individuals of S. horneri were amplified by PCR and analyzed, including wild populations from Huokun'ao of Nanji Island, Dongtou Island and Gouqi Island and Mazuao cultured population from Nanji Island in Zhejiang Province. The whole-length of sequence from all individuals was 1485 bp, including partial ITS1, ITS2 sequences, and complete 5.8S rDNA sequence. Among them, there was only one variable nucleotide site. It was suggested that there was no distinct genetic differentiation among populations with relatively low genetic diversity. In addition, 5.8S rDNA-ITS sequences from two haplotypes with the only one variable nucleotide site and another two sequences from GenBank public database were aligned, 31 variable nucleotide sites were detected, and 10 of them were insert or delete sites. Therefore, it was proposed to speed up the construction of artificial S. horneri field and restore wild S. horneri field in order to maintain an ecological balance.

Abstract:In order to evaluate the genetic character of sugarcane parents and the matching effect of cross combination, the economic breeding values of F₁ groups from 35 families were analysis by means of R Software and Australian family test, including plant height, diameter, number of stalk, cane yield and sugar content. The results showed that among 24 female parents, ROC22, Yuetang 92-1287, Neijiang 03-218, ROC25, HoCP 92- 648 were fit for productive females. Among 18 male parents, Yacheng 84-153, ROC22, Yuetang 00-319 were fit for productive males. The eight families, such as ROC22×Yacheng 84-153, Yuetang 92-1287×Yuetang 00-319, Neijiang 00-318×ROC22, ROC22×Yuetang 93-159, ROC25×Yuetang 93-159, Guitang 00-122×ROC22, Yacheng 97-46×ROC22, and HoCP92-648×ROC26, could be used as productive families, they might be breed new varieties with great economic benefit. So, it is suggested that these parents and families should be extent and used vigorously.

Abstract:In order to understand the effects of cutting intensity on niche of tree dominant species in natural secondary forest, the niche breadth, niche similarity proportion and niche overlap of 6 dominant species, such as Pinus massoniana, Schima superba, Daphnipyllum oldhamii, Castanopsis carlesii, C. eyrei and Adinandra millettii, under different selective cutting intensities were studied by quantitative investigation method. The results showed that the niche breadth of dominant species decreased with increment of selective cutting intensity, which were more than 0.5 except of Adinandra millettii. The species proportion of niche overlap above 0.8 also decreased with increment of selective cutting intensity. Under clear cutting, niche breadth of dominant species were less than 0.5, and species proportion of niche overlap above 0.8 only occupied 46.7%. It suggested that low and middle selective cutting intensity were helpful to keep wide niche breadth and ecological adaptability of dominant species. Therefore, rational selective cutting was beneficial to protect and utilization the mid-subtropical natural secondary forest, and favorite intensity was low or middle selective cutting intensities.

Abstract:In order to understand the community heterogeneity of fengshui woods in Guangzhou and its contribution to regional species diversity, sixty-seven fengshui wood patches in Guangzhou City, China were selected, in which a 20 m×20 m plot was set in each patch. The contribution of fengshui woods to regional species diversity was evaluated using extrapolation method of species area relationship and nonparametric method. The heterogeneity of fengshui wood communities was analyzed by separating γ-diversity according to additive rule. The results showed that at least 32.74% of regional species diversity was protected in fengshui woods. The γ-diversity (184) was mostly consisted of β-diversity (163.43) rather than α-diversity (20.57). Compared with plain region, fengshui wood community in hilly area had high species richness, phylogenetic diversity and more rare species. It was suggested that species composition in fengshui wood community had high spatial heterogeneity, and therefore it should protect fengshui wood patches as many as possible in order to preserve species diversity. Under the constraint conditions of funding and land resource, fengshui woods located in hilly areas should be preferentially considered.

Abstract:To reveal the effects of edge tropical and lower subtropical climatic conditions on indigenous trees in Guangdong Province, leaf structure characteristics of 8 indigenous greening species in Guangzhou and Zhanjiang were studied. The relationship between leaf mass per area (LMA) and leaf structure characters were analyzed. The results showed that leaf structure characters, i.e., fresh weight (FW), leaf length, leaf width, average leaf width and dry weight (DW), leaf area and leaf moisture content, had significant differences between two cities without consistent pattern. Specific leaf area (SLA) of Elaeocarpus apiculatus, Pterocarpus indicus, Lagetstroemia speciosa and Khaya senegalensis had significant difference between Zhanjiang and Guangzhou (P<0.001), while did not SLA of Michelia alba, Dracontomelon duperreranum, Bauhinia variegata and Ficus virens var. sublanceolata. The thickness (TH) of upper and middle leaves of Bauhinia variegata, upper leaves of Ficus virens var. sublanceolata, Lagerstroemia speciosa and Dracontomelon duperreanum in Guangzhou were larger than those in Zhanjiang (P<0.05). LMA had significantly positive correlation with FW and DW, and significantly negative correlation with leaf moisture content. There were not significant relation between LMA and leaf area, average leaf width and ratio of width to length. The climate conditions of two climate zones in Guangdong are differ litter, which not enough to make consistent adaptive variation of leaf structure characteristics in indigenous greening tree species.

Abstract:In order to find the antibacterial constituents of Ancistrocladus tectorius (Lour.) Merr., ten compounds were isolated from 95% EtOH extract of branches of A. tectorius by silica gel column chromatography, sephadex LH-20 column chromatography, and preparative HPLC. On the basis of physical characteristics and spectral data, they were identified as episyringaresinol (1), syringaresinol (2), pinoresinol (3), zhebeiresinol (4), 4-hydroxy- 3-methoxyphenthyl alcohol (5), ancistrocline (6), hamatine (7), ancistrocladine (8), ancistrotectorine (9), and β-daucosterol (10). Among them, compounds 1-5 were isolated from the genus Ancistrocladus for the first time, and compounds 1, 3, 4, and 6 showed inhibitory effect on Staphylococcus aureus by paper disk diffusion method.

Abstract:The aims was to understand the volatile components in leaves of Myrtaceae, six species, including Eugenia uniflora, Syzygium hainanense, S. hancei, Melaleuca bracteata, M. leucadendron, and Eucalyptus citriodora, were studied by SPME/GC/MS. The results showed that major volatile components in leaves of 6 Myrtaceous plants were terpenes, being rich in health protection components. The common volatile components were (Z)-β-ocimene, β-caryophyllene, myrcene, γ-terpinene and alloaromadendrene. It is suggested that the health function of volatile components from these Myrtaceous plants could be developed and utilized.