Alnus Formosana Research Articles

Root-soil facilitation in mixed Eucalyptus grandis plantations including nitrogen-fixing species

The success of mixed plantation systems is ultimately the net result of positive and negative interactions, including belowground interactions, among the respective species. Despite increasing knowledge on positive interactions on biomass and productivity in mixed-species plantations, relatively little is known about the mechanisms underlying belowground interactions. Based on biodiversity data from four mixed Eucalyptus grandis plantations, we determined the optimal ecological facilitative interactions of mixed plantation, i.e., E. grandis and Alnus formosana. We then investigated in situ root exudation of E. grandis using a cuvette-based method and analysed root patterns, defence chemicals, bacterial communities, and biochemical properties of rhizosphere soils in mixed E. grandis with alder. Compared with pure Eucalyptus plantations, the fine root production by E. grandis was higher in subsoil layers (40–80 cm) in mixed plantations with alder. Autotrophic root respiration and associated enzymes were also increased in mixed plantations. Root exudates and defence allelochemicals of E. grandis changed in the presence of alder. Compared with the pure Eucalyptus plantations, E. grandis roots in mixed plantations reduced the release of potential allelochemicals, such as phenolic acids, flavonoids, unsaturated lactone, and glycosides. Methyl jasmonate, a common signal chemical, was significantly decreased in mixed-species plantations. The bacterial community of E. grandis rhizosphere soil was improved in mixed stands and recruited more nitrifying, N-fixing, and cellulose-decomposing bacteria, such as family Nitrosomonadaceae, genera MND1, Marmoricola, and Rikenellaceae RC9 gut groups. Thus, belowground ecological facilitative interactions occurred in mixed plantations with alder, which were due to E. grandis altering its rooting pattern, reducing the levels of released allelochemicals, recruiting more beneficial bacteria, and improving the biochemical properties of rhizosphere soil. This mechanism may be useful in reforestation programs for Eucalyptus monocultures that are suffering from problems associated with low biodiversity and reduced soil fertility.

Evaluation of the effects of late-season fertilization on the growth, physiology, and nutritional status of Alnus formosana (Burkill) Makino

Evaluation of the effects of late-season fertilization on the growth, physiology, and nutritional status of Alnus formosana (Burkill) Makino

Characterization of the complete chloroplast genome of the Taiwan alder Alnus formosana (Betulaceae) based on next-generation sequencing technology

Alnus formosana (Betulaceae) is an important ecological and economic deciduous tree species widely distributed throughout subtropical regions of Taiwan province, China. At the present study, the complete chloroplast genome of A. formosana was assumbled using next-generation sequencing technology. The complete chloroplast sequence is 161,029 bp in length, which consisted of a large single copy (LSC, 89,720 bp) and a small single copy (SSC; 19,205 bp) separated a pair of inverted repeats (IRs; 26,052 bp). The overall guanine-cytosine (GC) content was 36.4%. A total of 131 genes were annotated, including 85 protein-coding genes, 37 tRNAs, eight rRNAs and one pseudogene (ψycf1). The phylogenetic analysis fully resolved A. formosana in a clade with A. japonica. The plastome of A. formosana will provide informative genomic resources for further phylogenetic application and genetic improvement.

Rapid Light-Response Curve of Chlorophyll Fluorescence in Terrestrial Plants: Relationship to CO2 Exchange among Five Woody and Four Fern Species Adapted to Different Light and Water Regimes.

The rapid light response of electron transport rate (ETRR), obtained from chlorophyll fluorescence parameters by short illumination periods (10–30 s) at each light level, can provide a rapid and easy measurement of photosynthetic light response in plants. However, the relationship between ETRR and the steady-state light response of CO2 exchange rate (AS) of terrestrial plants has not been studied in detail. In this study, we compared the ETRR and AS for five woody and four fern species with different light and/or water adaptations. Under well-watered conditions, a constant temperature (25 °C) and with stomatal conductance (gs) not being a main limiting factor for photosynthesis, ETRR and AS were closely related, even when merging data for regression analysis for a species grown under different light conditions and measured under different light intensity and air humidity. However, when Alnus formosana was treated with low soil water and air humidity, because of the decrease in AS mainly due to stomatal closure, the ETRR–AS relation was not so close. In addition, at both 100 and 2000 μmol m−2 s−1 photosynthetic photon flux density (PPFD), ETRR and AS were significantly correlated within a plant group (i.e., woody plants and ferns) regardless of the broad difference in AS due to different species or environmental factors. The results indicate that the relationship between the ETRR and AS is varied by species. We concluded that 1) ETRR could reflect the variation in AS at each irradiance level within a species under well-watered conditions and 2) ETRR at 100 μmol m−2 s−1 PPFD (as the efficiency of light capture) or 2000 μmol m−2 s−1 PPFD (as a maximum photosynthetic parameter) could be used to compare the photosynthetic capacity within a plant group, such as woody plants and ferns.

Impact of heavy metal ions on the simultaneous saccharification and fermentation of formosan alder biomass to form lactic acid

Formosan alder (Alnus formosana) is a fast-growing, adaptable, pioneer native tree species in Taiwan, and it is particularly suitable for reforestation. In this study, steam-exploded Formosan alder biomass was employed to investigate lactic acid production by simultaneous saccharification and fermentation (SSF) in the presence of different heavy metals. Impacts of added heavy metals on saccharification processing were investigated. In the presence of 1410 mg Cr6+/L, negative impacts were observed for SSF. The same level of Cr6+ adversely affected fermentation by Lactobacillus casei and L. acidophilus compared to the blank controls. Positive impacts for SSF by Cd2+ were demonstrated with 108 mg Cd2+/L, and the same conditions favored fermentation by L. casei and L. acidophilus. No impacts for SSF by Pb2+ up to 6830 mg Pb2+/L were found for both Lactobacillus strains. This study demonstrates that SSF for production of lactic acid from Formosan alder biomass was able to tolerate a wide range of heavy metal concentration regimes. Hence, this study provides an alternative use for biomass harvested from phytoremediation sites. Such biomass can be used as sustainable regenerative biomaterial, and thereby it can further enhance the benefits of environmental remediation.

English

Restoration of Alnus formosana (Burk.) Makino on landslide areas is important for agroforestry, forestry and soil erosion control in Taiwan. To ensure successful reforestation, A. formosana seedlings have to develop strong root system for nutrient and water acquisition as well as anchorage. Inoculating of A. formosana with symbiotic nitrogen-fixing actinobacteria Frankia may help mitigate drought and nutrient deficiencies on landslide sites. However, the effects of Frankia inoculation on growth, root architecture and mechanical properties of A. formosana seedlings are not well understood. In this research, a Frankia strain AF1 was isolated from actinorhizal nodules of local A. formosana and recognized as Frankia species, and its influences on growth performance and root mechanical properties of A. formosana seedlings were examined and analyzed. The results showed that the inoculated seedlings had significantly larger height and root biomass, longer root length, and more root tip number than that of the non-inoculated controls. Consistently, the inoculated seedlings had statistically significant higher uprooting resistance, root tensile resistance force and tensile strength than the controls. The results reveal that this native Frankia strain can promote growth performance, root system architecture, anchorage ability and root tensile strength of A. formosana. Key words: Actinorhiza, Betulaceae, inoculation, root morphology, tensile strength, uprooting resistance.

Differences in photosynthetic capacity, chlorophyll fluorescence, and antioxidant system between invasive Alnus formosana and its native congener in response to different irradiance levels

We compared the invasive Alnus formosana (Burk.) Makino with its native congener (Alnus cremastogyne Burk.) at three irradiances in terms of photosynthesis, chlorophyll fluorescence, and antioxidant system. The increased light-saturated photosynthetic rate (Amax) and light saturation point (LSP) contributed directly to the increased performance of the invasive. The invasive species had also higher plasticity in carotenoid and total chlorophyll than the native species at 100% irradiance, potentially contributing to invasion success in high-irradiance locations via photoprotection. Moreover, the diurnal photoinhibition of photosynthesis, as judged by the maximum photochemical efficiency of PSII (Fv/Fm) of dark-adapted leaves, was more severe in the native species than in the invasive species. With increasing irradiance, the invasive exhibited increased antioxidant activities and higher antioxidant levels to support the adverse conditions of both low- and high-irradiance acclimation. In contrast, the intercellular CO2 concentration (Ci) and stomatal limitation (Ls) decreased with increases in the net photosynthetic rate (An), stomatal conductance (Gs), and transpiration rate (Tr). We speculated that Ls was the main factor inhibiting the An for both studied species. These results first indicated that the invasive may occupy new habitats successfully through tolerating shading at low irradiance and out-compete native species through higher Amax and antioxidant levels when irradiance is increased.

High resource-capture and -use efficiency, and effective antioxidant protection contribute to the invasiveness of Alnus formosana plants

To investigate the traits contributing to the invasiveness of Alnus formosana and the mechanisms underlying its invasiveness, we compared A. formosana with its native congener (Alnus cremastogyne) under three light treatments (13%, 56%, and 100%). The consistently higher plant height, total leaf area, light-saturated photosynthetic rate (Amax), light saturation point (LSP), light compensation point (LCP), respiration efficiency (RE), and non-photochemical quenching coefficient (NPQ) but lower root mass fraction (RMF) and specific leaf area (SLA) of the invader than of its native congener contributed to the higher RGR and total biomass of A. formosana across light regimes. The total biomass and RGR of the invader increased markedly with increased RMF, Amax, LSP, LCP, RE, stomatal conductance (Gs) and total leaf area. Furthermore, compared with the native species, the higher plasticity index in plant height, RMF, leaf mass fraction (LMF), SMF, SLA, Amax and dark respiration rate (Rd) within the range of total light contributed to the higher performance of the invader. In addition, the activities of antioxidant enzymes were higher in the invader compared to the native, contributing to its invasion success under high/low light via photoprotection. With a decrease in light level, superoxide dismutase (SOD) and catalase (CAT) activities increased significantly, whereas total carotenoid (Car) and total chlorophyll (Chl) decreased; ascorbate peroxidase (APX) and glutathione reductase (GR) activities remained unchanged. These responses may help the invader to spread and invade a wide range of habitats and form dense monocultures, displacing native plant species. The results suggest that both resource capture-related traits (morphological and photosynthetic) and adaptation-related traits (antioxidant protection) contribute to the competitive advantage of the invader.

Carbon storage potential of avenue trees: a comparison of Barringtonia racemosa, Cyclobalanopsis glauca, and Alnus formosana

Trees in cities play a valuable public health role for they are able to use photosynthesis to absorb atmospheric carbon dioxide (CO2), which is then stored as tree biomass. The present study compared the potential for carbon storage in the aboveground tree biomass of 3-year-old specimens of Barringtonia racemosa, Cyclobalanopsis glauca, and Alnus formosana grown in Chiayi City, Taiwan. Assessment of the carbon storage of avenue trees was based on measurement of the photosynthetic rate and leaf area, as well as the biomass of timbers, from October 2008 to 2009. Based on photosynthetic rates and leaf area, the estimated carbon stocks of B. racemosa, C. glauca, and A. formosana are 756, 615, and 2738 kg Cha−1 a−1, respectively. In addition, carbon storage can be estimated based on timber volume, and these results are 1170, 720, and 1995 kg Cha−1 a−1 for B. racemosa, C. glauca, and A. formosana, respectively. Based on these findings, A. formosana has the highest carbon fixation potential of these three trees. Although the photosynthetic rate measurements can provide detailed data on the diurnal changes in carbon stocks, this requires more time and labor. In contrast, timber volume measurements provide a rapid and convenient way to estimate carbon stocks.

Aneuploidy Alnus formosana Selection and ISSR Analysis

the chromosomal counting was carried out with 51 of annual Taiwan alder (Alnus formosana) by the wall degradation and hypotonic flame-drying method, and 6 aneuploid plants has been selected from these seedings. The viable aneuploid chromosome numbers included 2n=52 (No.4),2n=42 (No.19),2n=54(No.21),2n=50(No.24),2n=56,112 (No.25),2n=52(No.33). Subsequently, the ISSR was taken to analyze the genome of these aneuploid plants,and 5 primers were obtained from 57 which could separate 6 aneuploid plants. And the ratio of polymorphism was more than 78.2%.

Physical and Mechanical Properties of Alnus Formosana Wood Introduced into Sichuan

The mechanical and physical properties of Alnus formosana wood from Sichuan, China were studied. Air-dry density, oven-dry density, basic density, shrinkage, swelling, parallel-to-grain compressive strength, parallel-to-grain tensile strength, modulus of rupture (MOR),modulus of elasticity (MOE) ,impact toughness were analyzed. Results from this study show that air-dry density, oven-dry density and basic density were respectively 0.52, 0.49 and 0.43g/cm3. The average value of volumetric shrinkage was 7.111% and the average value of volumetric swelling was 7.06%. The average values of modulus of elasticity (MOE) ,modulus of rupture (MOR), parallel-to-grain compressive strength, parallel-to-grain tensile strength and impact toughness were 8102.429 Mpa, 80.429 Mpa, 41.575Mpa, 81.542 Mpa and 47.406 Kj/m2 , respectively. This study solved a basic problem about the planting and utilization of Alnus formosana wood in Sichuan, China.

Admixture of alder (Alnus formosana) litter can improve the decomposition of eucalyptus (Eucalyptus grandis) litter

The slow nutrient turnover of eucalyptus (Eucalyptus grandis) plantations has been well documented. To examine whether the admixture of alder (Alnus formosana) litter could improve the decomposition of eucalyptus litter, a field litterbag experiment was conducted on a new eucalyptus plantation in southwestern China. We investigated the mass loss rate from an alder and eucalyptus foliar litter mixture every half month from May 1st to October 1st, 2009. Five mixture proportions were examined: pure eucalyptus litter (10E), 70% eucalyptus litter mixed with 30% alder litter (7E:3A), 50% eucalyptus litter mixed with 50% alder litter (5E:5A), 30% eucalyptus litter mixed with 70% alder litter (3E:7A) and pure alder litter (10A). Over 169 days of decomposition, approximately 79.22%, 70.23%, 62.82%, 49.95% and 48.59% of mass was lost from the 3E:7A, 10A, 5E:5A, 7E:3A and 10E litter mixtures, respectively. Compared with pure eucalyptus litter, 3E:7A, 10A, 5E:5A and 7E:3A litter mixtures increased 63.04%, 44.54%, 29.29% and 2.80% of accumulated mass loss. The admixture of alder litter can significantly improve eucalyptus litter decomposition, and a small proportion of eucalyptus litter (3E:7A) may also promote alder litter decomposition. As the decomposition proceeded, the litter mixture displayed exactly additive effects in the initial stage and positive non-additive effects in the middle stage. However, negative non-additive effects were detected in the 7E:3A litter mixture in the later stage, although positive non-additive effects were maintained throughout decomposition in the 5E:5A and 3E:7A mixtures. Compared to pure eucalyptus litter, mixtures containing alder litter presented increased microbial biomass carbon and bacterial DGGE (Denaturing Gradient Gel Electrophoresis) bands, but the litter mixture decomposition relied more on microbial biomass than on microbial diversity. The results imply that alder litter can improve material cycling on eucalyptus plantations and that alder could be a potential species for mixed planting with eucalyptus.

Effects of fertilization on Alnus formosana fine root morphological characteristics, biomass and issue content of C, N under A. formosana-Hemarthria compressa compound mode

Aims Our objectives were to: 1) examine fine root biomass, morphological characteristics and content of C and N of Alnus formosana in an A. formosana-Hemarthria compressa composite model in Danling, Sichuan Province, China, 2) examine the effects of fertilization on each order of fine roots, and 3) analyze the relationship between soil nutrients and fine root biomass, architecture and content of C and N. Methods In September 2010, we established two subdistricts, eradicated weeds and planted H. compressa. We fertilized one subdistrict with N-P-K fertilizer in April, June, August and October and did not fertilize the other subdistrict. We excavated soil blocks of 20 cm × 20 cm × 10 cm (height) to sample intact fine root branches of at least the first branch orders. We dissected the intact root branches by orders and measured the diameter, specific root length, biomass, and C and N content of each order. Important findings Fertilization reduced fine-root average diameter in soil surface and increased that in soil subsurface. In fine-root orders 1–5, specific root length increased as root order decreased. Fertilization significantly increased specific root length in fine-root orders 1–3 in soil surface and subsurface (p 0.05). Soil surface total N content of fine roots of 1–5 苗宇等: 施肥对台湾桤木-扁穗牛鞭草复合模式下桤木细根形态特征、生物量及组织碳氮含量的影响 675 doi: 10.3724/SP.J.1258.2013.00070 orders was higher than that in subsurface. Fertilization significantly (p 0.05).

The Response of SOC Content and Seasonal Dynamics of Three <i>Alnus formosana</i> Forests under Different Herb Layer to the Fertilization

Alnus formosana + Hemarthria compressa (A+H), Alnus formosana + Lolium multiflorum Lam (A+L), and Alnus formosana + natural grass (A+N), the comparative analysis of SOC(SOC) content, vertical distribution and seasonal dynamics of the three kinds of forest modes and the response of which to the fertilization suggests that the content of the SOC of the three kinds of forest lands under different herb layer in the soil which has been fertilized and unfertilized respectively are: A+L >A+H >A+N. The results mainly caused by the differences among herb layers. The vertical distribution law of organic carbon is no difference among three kinds of modes that the content of organic carbon would be decreased with the depth of soil layers. However, the reduction rate of organic carbon content in soil layers in the depth 0~20cm is more obvious than in 20~40cm. Fertilization can increase the SOC content, and especially in the shallow surface. The seasonal dynamics of the three kinds of SOC modes are basically same: the SOC content will reach the minimum in autumn, and then it will be gradually increased until the maximum is reached in the next summer. The main characteristic is that the relatively higher content of SOC is presented in spring and summer, which on the contrary in autumn and winter. The seasonal dynamics of SOC is insignificantly influenced by fertilization. For the soil organic content, the A+L is better than the A+H.

Effects of light regimes on photosynthetic characteristics and antioxidant system in seedlings of two alder species

Aims Our objective was to investigate the effects of different light intensities on leaf morphology, photosynthetic capacity, heat dissipation and antioxidant enzyme activities in seedlings of Alnus formosana and A. cremastogyne from a hilly region near Lingyan Mountain in northwestern Sichuan Province in China. We also discuss photosynthetic acclimation and photoprotection strategies in seedlings of the two species Methods Three light regimes of 100%, 56.2% and 12.5% of natural light were simulated to match forest openings, forest gaps and forest canopies, respectively. After more than three months, we measured the parameters of gas exchange, including maximum net photosynthetic rate (Pmax), light saturation point (LSP), light compensation point (LCP), net photosynthetic rate (P n ), stomatal conductance (G s ), transpiration rate (T r ), intercellular CO 2 concentration (C i ), fluorescent non-photochemical quenching (NPQ), maximum efficiency of PSII photochemistry (F v /F m ) and light use efficiency (LUE), using a LI-6400 in seedling leaves. We also determined pigment contents per unit leaf area, lamina mass per unit area (LMA) and activity of antioxidant enzymes (superoxide dismutase, catalase and ascorbate peroxidase). Important findings LMA, carotenoid content (Cars), ratio of carotenoid to total chlorophyll (Car/Chl) and activities of superoxide dismutase, catalase and ascorbate peroxidase in leaves increased with the increase of light intensities. P max , LSP, LCP and NPQ tended to increase, while the chlorophyll content (Chl) and LUE decreased. However, the C i decreased with the increase of P n , G s and stomatal limitation value (L s ). We speculated that non-stomatal limitation was the main factor that inhibited P n . Seedlings of the two alder species could acclimate to different light regimes in this study through changing of physiological and morphological traits. Under all lightregimes, diurnal photoinhibition of photosynthesis, as judged by F v /F m , was significantly more severe in A. cremastogyne than in A. formosana. The acclimation capacity to high light regime was stronger in A. formosana than in A. cremastogyne. With the increase of light intensities, P max and antioxidant enzyme activities increased significantly, but not NPQ in A. formosana. The opposite trends occurred in A. cremastogyne. At the same light intensity, thermal dissipation was much lower, but P max was much higher in A. formosana than in A. cremastogyne. These results indicated that A. formosana seedlings might adapt resistance to photoinhibition through improving the use of solar energy by higher P max and antioxidant enzyme system, while A. cremastogyne seedling avoided photoinhibition mainly through converting excess light energy to heat energy in the form of non-radiative dissipation through the antenna system.

Using combined measurements for comparison of light induction of stomatal conductance, electron transport rate and CO2 fixation in woody and fern species adapted to different light regimes

We aimed to understand the relation of photosynthetic rate (A) with g(s) and electron transport rate (ETR) in species of great taxonomic range and light adaptation capability during photosynthetic light induction. We studied three woody species (Alnus formosana, Ardisia crenata and Ardisia cornudentata) and four fern species (Pyrrosia lingus, Asplenium antiquum, Diplazium donianum and Archangiopteris somai) with different light adaptation capabilities. Pot-grown materials received 100 and/or 10% sunlight according to their light adaptation capabilities. At least 4 months after light acclimation, CO(2) and H(2)O exchange and chlorophyll fluorescence were measured simultaneously by equipment in the laboratory. In plants adapted or acclimated to low light, dark-adapted leaves exposed to 500 or 2000 µmol m(-2) s(-1) photosynthetic photon flux (PPF) for 30 min showed low gross photosynthetic rate (P(g)) and short time required to reach 90% of maximum P(g) (). At the initiation of illumination, two broad-leaved understory shrubs and the four ferns, especially ferns adapted to heavy shade, showed higher stomatal conductance (g(s)) than pioneer tree species; materials with higher g(s) had short at both 500 and 2000 µmol m(-2) s(-1) PPF. With 500 or 2000 µmol m(-2) s(-1) PPF, the g(s) for the three woody species increased from 2 to 30 min after the start of illumination, but little change in the g(s) of the four ferns. Thus, P(g) and g(s) were not correlated for all material measured at the same PPF and induction time. However, P(g) was positively correlated with ETR, even though CO(2) assimilation may be influenced by stomatal, biochemical and photoinhibitory limitations. In addition, was closely related to time required to reach 90% maximal ETR for all materials and with two levels of PPF combined. Thus, ETR is a good indicator for estimating the light induction of photosynthetic rate of species, across a wide taxonomic range and light adaptation and acclimation capability.

Using combined measurements of gas exchange and chlorophyll fluorescence to investigate the photosynthetic light responses of plant species adapted to different light regimes

One broad-leaved pioneer tree, Alnus formosana, two broad-leaved understory shrubs, Ardisia crenata and Ardisia cornudentata, and four ferns with different light adaptation capabilities (ranked from high to low, Pyrrosia lingus, Asplenium antiquum, Diplazium donianum, Archangiopteris somai) were used to elucidate the light responses of photosynthetic rate and electron transport rate (ETR). Pot-grown materials received up to 3 levels of light intensity, i.e., 100%, 50% and 10% sunlight. Both gas exchange and chlorophyll (Chl) fluorescence were measured simultaneously by an equipment under constant temperature and 7 levels (0-2,000 μmol m-2 s-1) of photosynthetic photon flux density (PPFD). Plants adapted to-or acclimated to high light always had higher light-saturation point and maximal photosynthetic rate. Even materials had a broad range of photosynthetic capacity [maximal photosynthetic rate ranging from 2 to 23 μmol(CO2) m-2 s-1], the ratio of ETR to gross photosynthetic rate (P G) was close for A. formosana and the 4 fern species when measured under constant temperature, but the PPFD varied. In addition, P. lingus and A. formosana grown under 100% sunlight and measured at different seasonal temperatures (15, 20, 25, and 30°C) showed increased ETR/P G ratio with increasing temperature and could be fitted by first- and second-order equations, respectively. With this equation, estimated and measured P G were closely correlated (r 2 = 0.916 and r 2 = 0.964 for P. lingus and A. formosana, respectively, p<0.001). These equations contain only the 2 easily obtained dynamic indicators, ETR and leaf temperature. Therefore, for some species with near ETR/P G ratio in differential levels of PPFD, these equations could be used to simulate dynamic variation of leaf scale photosynthetic rate under different temperature and PPFD conditions.

A comprehensive investigation of anti-inflammatory diarylheptanoids from the leaves of Alnus formosana

This study was aimed to investigate thoroughly the diarylheptanoids in the n-BuOH soluble fraction of leaves of Alnus formosana in order to examine their anti-inflammatory activities. The application of HPLC-SPE-NMR as a preliminary chemical screening led to characterization of eleven compounds. Further separation resulted in isolation of 28 compounds, of which 10 diarylheptanoids and 2-coumaroylxyloside are new natural products. Compound 1 and alnuside A ( 27) were found to possess good activities against LPS-induced NO production with respective IC 50 values of 7.99 and 8.08 μM, and which were devoid of significant cytotoxicity.

Species identification of Alnus (Betulaceae) using nrDNA and cpDNA genetic markers

One nuclear and three chloroplast DNA regions (ITS, rbcL, matK and trnH-psbA) were used to identify the species of Alnus (Betulaceae). The results showed that 23 out of all 26 Alnus species in the world, represented by 131 samples, had their own specific molecular character states, especially for three morphologically confused species (Alnus formosana, Alnus japonica and Alnus maritima). The discriminating power of the four markers at the species level was 10% (rbcL), 31.25% (matK), 63.6% (trnH-psbA) and 76.9% (ITS). For ITS, the mean value of genetic distance between species was more than 10 times the intraspecific distance (0.009%), and 13 species had unique character states that differentiated them from other species of Alnus. The trnH-psbA region had higher mean values of genetic distance between and within species (2.1% and 0.68% respectively) than any other region tested. Using the trnH-psbA region, 13 species are distinguished from 22 species, and seven species have a single diagnostic site. The combination of two regions, ITS and trnH-psbA, is the best choice for DNA identification of Alnus species, as an improvement and supplement for morphologically based taxonomy. This study illustrates the potential for certain DNA regions to be used as novel internet biological information carrier through combining DNA sequences with existing morphological character and suggests a relatively reliable and open taxonomic system based on the linked DNA and morphological data.

Chemical Constituents from Alnus formosana Burk. III. Polar Constituents from Leaves by HPLC-SPE-NMR and Conventional Methods

This continual study was aimed to investigate thoroughly the polar constituents present in the n-BuOH- soluble fraction of the leaves of Alnus formosana. [1] The HPLC-SPE-NMR hyphenated technique was applied for such purpose. This effort led to the characterization of 44 compounds, including thirty diarylheptanoids, ten flavonoids, and a coumaroylxyloside. Of these, seventeen compounds (1-1 7) are new. These compounds were further isolated and the structures were confirmed by general spectroscopic analysis.