A total of six rice genes of functional importance, including Osgstf3, OsNAC6, BADH, XCP2, EMF2 and ERCC4, were selected to assess suitable SNPs for use in an analysis of population genetic structure of Oryza granulata, a precious wild relative of Asian cultivated rice. An initial survey of 12 representative samples of O.granulata from Yunnan and Hainan, China, resolved few SNPs in Osgstf3, OsNAC6, BADH and XCP2, while low levels of variation were recorded within introns of EMF2 and ERCC4. A subsequent SNP survey was conducted within the EMF2 and ERCC4 fragments across a sample of 52 plants collected from three and two natural populations in Yunnan and Hainan, respectively. This survey showed that O.granulata exhibits fairly high genetic divergence between populations despite low levels of nucleotide diversity. Genetic divergence between populations was evident both between and within geographical regions. These findings imply that recent habitat fragmentation in tropical and subtropical forests led to severe restrictions to gene flow, which enhanced divergence among populations.
It is difficult to identify Chinese species of Acacia accurately based on morphological assessment unless an intact specimen is at hand. In contrast, DNA barcoding through the analysis of short DNA sequences from a small sample of tissue can provide an accurate method for identifying species. In this study, we used four DNA fragments (rbcL, matK, psbAtrnH, and ITS) to develop a potential barcoding method for Chinese Acacia. Our analysis involved calculating inter and intraspecific genetic distances, conducting Wilcoxon signed rank tests to analyze the sequence variation, and constructing phylogenetic trees from distance data. The results showed that barcoding gaps exist between Acacia species for each of the four sequences, with ITS showing highest interspecific divergence. Both the use of ITS on its own and in combination with rbcL sequence variation gave the highest level of species identification. We therefore propose the use of ITS sequence variation on its own or combined with rbcL as a DNA barcode for identifying Acacia species in China.
Anemoclema W.T. Wang, a monotypic genus of Ranunculaceae, is endemic to the Jinsha River Valley in southwest China. Combining field investigation with molecular marker analysis (SNPs), we investigated the genetic diversity and genetic structure of A.glaucifolium. Analysis of three chloroplast DNA (cpDNA) regions (rps16 intron, psbAtrnH intergenic spacer and trnCycf6 intergenic spacer) revealed a low level of genetic diversity within the species, but high divergence among populations. This genetic structure is possibly caused by a long period of historical geographic isolation, a relatively narrow distribution range and limited gene flow due to habitat fragmentation. Hydropower stations are scheduled to be built in the Jinsha River drainage system in areas that overlap the range of A.glaucifolium and as a result of their construction the habitats of A.glaucifolium will be flooded or adversely affected in other ways, thus threatening the survival of the species. The results of our analysis of genetic diversity in A.glaucifolium are of value for developing an appropriate conservation strategy for this vulnerable species.
Nonspecific Lipid transfer proteins (nsLTPs) were a group of important active proteins in in higher plants. Their function has been suggested to have a role in plant resistance and defense response. According to recent studies, LTPs play an important role in plant reproduction and development. In this study, BjLTP was cloned from Brassica juncea var. multiceps based on BcMF15 from Brassica campestris ssp. chinensis var. communis BjLTP was 650bp (EU082009) in length with no intron. RTPCR analysis showed that BjLTP was expressed in flower buds and open flower but not other tissues. The gene may act as nsLTPs involving in pollen development. Protein characteristics and sequence structure were predicted, that it was a transmembrane protein with obvious hydrophobic region. BjLTP was identified as a Lipid transfer protein gene according to its high identity with Brassica oleracea (MF15bh) and Arabidopsis thaliana LTP.
Alterations of membrane fluidity and permeability are an inherent feature of deterioration associated with senescence in plants. With regard to membrane lipid constituents, the occurrence of lysophospholipid (lysoPL) is a signal of membrane damage, while changes in the double bond number of membrane lipids has important effects on membrane fluidity. In the present study, a lipidomics approach was used to study changes in lysoPL molecular species, and, in addition, the double bond index (DBI) of membrane lipids was calculated to indicate membrane fluidity in wild type (WS) and a phospholipid Dδ (PLDδ) knockout mutant of Arabidopsis during detachmentinduced, abscisic acid (ABA) or ethylenepromoted senescence. The results indicated that the content of total lysoPLs and some lysoPL molecular species increased markedly during ABApromoted senescence, while no significant change was detected during detachmentinduced and ethylenepromoted senescence. The DBI of total membrane lipids decreased during three senescence treatments; however, the pattern of change for each membrane lipid class differed between detachmentinduced and hormonepromoted senescence. Suppression of PLDδ attenuated lysoPLs accumulation during ABApromoted senescence, and slowed down the decrease of DBI of the total membrane lipids during ABA and ethylenepromoted senescence.
Genetic diversity across five sampled populations of Rhododendron shanii Fang was analyzed using ISSR molecular markers. A total of 69 loci, 36 of which were polymorphic, were detected using 8 ISSR primers. At the species level, total percentage of polymorphic loci (P) was 52.17%, and Shannon’s information index (I) and Nei’s gene diversity (h) were 0.2536 and 0.1659, respectively. At the population level, the mean value of P, I and h were 32.46%, 0.1955 and 0.1344, respectively. The coefficient of genetic differentiation (GST) was 0.1845 and the gene flow (Nm) was 2.2104. Analysis of molecular variance (AMOVA) demonstrated that the within populations component accounted for 88.3% of the total variation, while the among populations component accounted for 11.7%. The results of principal component analysis (PCA) and Neighborjoining also revealed that differences among populations were small and most genetic diversity was present within populations. Mantel’s test showed there was significant correlation between genetic and geographical distance. The pattern of genetic structure recorded in R.shanii possibly stems from fairly frequent geneflow among populations, a perennial woody habit and a limited distribution range. At present, priority must be given to in situ conservation of extant populations. In this regard, attention should be paid to large populations of R.shanii, which appear to contain most of the genetic diversity present within the species.
A pair of degenerate primers was designed according to reported fragments of LEA3 genes in GenBank. Using these primers a new cDNA fragment of 1032bp was amplified by PCR and RACE from total RNA of Sorghum bicolor, which indicated that the open reading frame region of the gene was 612bp (GenBank accession number GQ494000). It is predicted that the sequence encodes 203 amino acids with a molecular weight of about 21.22kD, includes seven characteristic motifs of LEA3 and has a theoretical isoelectric point of 8.79. The sequence shows a similarity of 73.8%, 53.77%, 45.63% and 53.99% with Zea mays, Triticum aestivum, Oryza sativa and Hordeum vulgare LEA3 sequences, respectively. The secondary structure of the Sorghum LEA3 protein exhibited a quantity of αhelix dominant structures that were similar to those found in many other plants. In addition, a 749bp DNA sequence was isolated from Sorghum genomic DNA by Thermal Asymmetric Interlaced PCR (TailPCR). This promoter region was predicted to contain ABA and drought stress response elements of embryo and endospermspecific genes Sequences of Gramineae LEA3 genes were aligned using the profile alignment function of ClustalX, and maximum likelihood phylogenetic analyses were conducted using PHyML. The research forms part of an analysis of droughtresistant mechanisms and gene function in Sorghum.
Species of Paris (Trilliaceae) have often been used as medicinalplants. Because of excessive exploitation,in this regard the wild resource of Paris is almost exhausted. Some species of Paris were transplanted for use in photosynthesis research and for conservation purposes. In the present study, light and CO2 photosynthetic response curves were investigated in four Paris taxa: P.polyphylla var. yunnanensis and var. alba, P.mairei, and P.marmorata. Our results showed that P.marmorata had the highest maximum photosynthetic rate (Pmax; 8.6μmol·m-2·s-1), light saturation point (LSP; 827μmol·m-2·s-1), maximum electron transport rate (Jmax; 39.9mol·m-2·s-1), a relatively high maximum carboxylation rate (Vcmax; 28.9μmol·m-2·s-1) and carbon dioxide saturation point (Cisat; 726μmol·mol-1), but a lower light compensation point (LCP; 6.23μmol·m-2·s-1) and the lowest carbon dioxide compensation point (Г*; 20.7μmol·mol-1). This suggests that P.marmorata is well adapted to light and CO2; however it has a low ability to acclimate to environmental stress as indicated by low water use efficiency (WUE) in high light conditions. P.polyphylla var. yunnanensis had the highest light compensation point (LCP; 10.1μmol·m-2·s-1), carbon dioxide compensation point (Г*; 35.3μmol·mol-1), carbon dioxide saturation point (Cisat; 727μmol·mol-1), relatively high maximum photosynthetic rate (Pmax; 7.5μmol·m-2·s-1) and light saturation point (LSP; 728μmol·m-2·s-1), maximum lightsaturated electron transfer rate (Jmax; 37.7μmol·m-2·s-1), suggesting that it is suitable for conditions of higher light and CO2 concentration. This taxon can adapt to adverse conditions, as suggested by high WUE under increased CO2 concentration. In contrast, P.polyphylla var. alba exhibited a relatively lower apparent quantum yield (AQY; 0.037μmol·mol-1) and poorer growth performance than the other taxa. We suggest from our results that different light and water conditions are suitable for the growth of the different taxa. Photosynthesis assimilation efficiency and production can be increased by raising humidity for P.polyphylla var. yunnanensis and P.marmorata. To protect plants of P.polyphylla var. alba from strong sunshine, they should be shaded from March to mid June.
In this work, the chromosome numbers and karyomorphology analyses were carried out on five species of Cycas L. from the south China. The data about C.hongheensis, C.segmentifida and C.shiwandashanica are reported for the first time. The chromosome counts of five species are 2n=2x=22.
Revision of some newly and previously published taxa of the woody bamboos, or the Bambusoideae in China resulted in some nomenclatural changes for the Flora of China. Based on recent molecular analyses, the delimitation of Arundinaria s.l. is not confirmed. Four species treated in Arundinaria in the Flora are currently resurrected in Bashania. With six additional species not accepted or treated in the Flora, there are 10 species of Bashania in China. Specimens used for Neomicrocalamus microphyllus (nom.nud.) should be treated in N.prainii, while N.yunnanensis is possibly a member of Melocalamus, not of Neomicrocalamus.
Flexistyly is a floral mechanism involving extreme curving of the style first described in Amomum tsaoko Crevost & Lemarie. We examined the influence of temperature and humidity on stylar curvature in this species. Although floral behavior was similar to that reported previously in this species and other flexistylous gingers, there was a delay in stylar movement in two morphs, which differed strikingly from previous observations. When mean temperature and humidity between 8∶30 and 19∶30 hrs were below 18℃ and above 90%, respectively, style movement of both morphs was not delayed; however, there was a delay in style movement when temperature was increased above 18℃ and humidity fell below 90%. Stylar curvature of cataflexistylous flowers was more sensitive to change of humidity than anaflexistylous ones. When mean temperature and humidity were between 19.17-19.52℃ and 51.00%-51.44%, respectively, the anthesis of a single cataflexistylous flower was prolonged from 1 day to 2 days, and stylar curvature downwards was asynchronous. The asynchronous stylar movement did not ensure complete functional dioecy within a population, which would decrease successful crossfertilization (outcrossing) between the two different forms, and affect the breeding and fitness of plants. Flexistyly is a special form of heterodichogamy, which requires further study to fully understand its origin and evolution.
To evaluate the use of protospecies in the breeding of cultivated sugarcane, we examined 50 protospecies for ratoon character variation. Ratoon germination rate varied between 7% and 184%, and the ratio of productive tiller between 0 and 360%. The best materials in regard to effective stem, plant height, stem diameter, brix and sucrose were Guangze bamboo cane, Sichuan reed cane, badila, Deyang large leaves and 28NG251. Two good traits were exhibited by 21 protospecies, three good traits by 11 protospecies, and four good traits by 14NG124. Infection rate of S.sinense R by mosaic disease and smut was higher than in S.officinarum L. and S.barberi J. It was noted that Deyang big leaves, Guangxi bamboo cane and Wenshan cane were also infected by mosaic disease and smut.
The potential of woody plants in Yunnan for biodiesel production was examined. We selected the oil content, oil component, fruit characters, distribution range and propagation characters as evaluation indices, and used the grey correlation degree analysis to comprehensively evaluate 188 woody oilbearing plants (oil content≥30%). Our results showed that the correlation degrees between the ideal species and 29 woody oilbearing plants were all higher than 0.6500. The correlations for Neocinnamomum caudatum and Camellia pitardii were particularly good, and after further research these species may be possible candidates for biodiesel development. Daphniphyllum paxianum, Evodia trichotoma and Toxicodendron grangiflorum var. longipes were three newly discovered woody oilbearing plants that also have potential for biodiesel development.
Research on Toona sinensis is important for its cultivation in China and provision of a highquality timber resource. We used the GB1927-91 Test Method to examine the anatomy and physicomechanical properties of Toona sinensis wood. We found that fiber morphology is shaped, on average, after 13 years of growth, with an aspect ratio of 46.18, double wall thickness of 11.00μm, fiber wall cavity ratio of 0.56, and cavity diameter ratio of 0.76. Average length and width of vessel elements was 383.52μm and 143.98μm, respectively, basic density was 0.415g/cm3 and air dry density was 0.475g/cm3. The wood may be described as a “light and low type” timber with differences in shrinkage of 1.93, wood bending strength, modulus of elasticity and compressive strength of grain rolls of 67.85MPa, 6179.82MPa and 38.23MPa, respectively, an integrated strength of 106.08MPa, and a comprehensive quality factor of 2556.1×105Pa. Based on our findings, Toona sinensis may be considered to produce a form of high-quality wood.
The integration of new statistical techniques and increasing availability of multisources and multiscale data sets promote the development of species distribution modeling. Yet, choice of data sets, different model types and their underlying ecological theories and assumptions can cause uncertainty in model predictions. In order to decrease prediction uncertainty, studies using model ensemble are gaining in popularity. In this paper we apply the BioMod package developed under R environment to predict the spatial distribution of Tsuga chinensis using nine different models. Our aims were to evaluate model performance, select explanatory variables, and assemble the best predictive output. Random Forest, MARS and GAM performed the best amongst the nine models compared, while SRE was the worst. The ensemble models predicted that the areas of high probability for T.chinensis presence lie mainly in Southwest China and the periphery of the Sichuan basin, and are also distributed sporadically in South China and Taiwan. These predictions reflect the actual distribution pattern of T.chinensis, and show high agreement with other analyses. The application of BioMod for model ensemble lowers uncertainty and improves the prediction performance.
Based on the “Forest Ecosystem Services Assessment Standards” (LY/T1721-2008) issued by the State Administration of Forestry, the forest ecosystem services of all the national and provincical nature reserves in Yunnan Province were evaluated using the public data issued by the authoritative departments and the technical literature data by published publicly. The matter quantity and value of forest ecosystem reflected in service functions including water conservation, soil conservation, carbon fixing and oxygen releasing, nutrient accumulation, atmospheric environment decontaminating and biodiversity conservation were evaluated. The forest service functions were analyzed from different perspectives such as vegtation types, stand quality, soil types and site conditions as well.The results showed that the total value of these six forest ecosystem services in all the national and provincial nature reserves of Yunnan province were RMB 200.902 billion per year, of which the value of water conservation, soil conservation, carbon fixing and oxygen releasing, nutrient accumulation, atmospheric environment decontaminating and biodiversity conservation, accounted for RMB 53.875 billion, RMB 49.379 billion, RMB 12.209 billion, RMB 1.611 billion, RMB 8.321 billion and RMB 75.507 billion respectively. The annual average forest ecosystem service of nature reserves in Yunnan Province is RMB 123.1 thousand per hectare, which was 2.9 times equivalent to the national average, and 2.4 times to the average level of Yunnan Province.
An evaluation of scientific papers on halophytes was conducted on 447 articles indexed by the Chinese Science Citation Database (CSCD) and 3329 articles indexed by the VIP, WANFANG and CNKI. Articles were reviewed and evaluated according to year produced, research institution, authors, source journal, subject category, number of citations, and keywords based on bibliometrics. Research focus, regions, content, technology, method, talents, main scientific research institution and teams were summarized and analyzed, and research progress of halophytes was described. Our results indicate that starting from 1956, most articles were published in 2007 (340 articles). However, according to CSCD (starting from 1991) most articles were published in 2011. Overall, the number of articles published increased year by year. Four main research teams focus on halophytes in China These are located in Shandong Normal University, Xinjiang Institute of Ecology and Geography of Chinese Academy of Sciences, China Agricultural University and Nanjing University. Active regions of China for halophyte research include Xinjiang, Shandong, Beijing, Nanjing, the northeast, Inner Mongolia, Ningxia and Lanzhou. Research focuses on salt tolerance and its mechanism, salt stress, salinealkali soils, gene cloning, soil salinity, plant growth, resource development and utilization, osmotic adjustment, physiological index, seed germination, proline, genetic engineering (genetic expression) and phytocoenosium.
