2015 Vol. 33 No. 6
2015, 33(6): 727-733.
DOI: 10.11913/PSJ.2095-0837.2015.60727
Abstract：
The Indigofera szechuensis complex contains nine species: I. szechuensis, I. pendula, I. hancockii, I. franchetii, I. delavayi, I. lenticellata, I. rigioclada, I. calcicola and I. heterantha. In this study, we conducted morphological and ITS variation analyses of 240 samples from 31 populations. Analysis of means showed that the nine species of the I. szechuensis complex mainly differed in leaflet size and inflorescence length. Principal component analysis indicated that the maximal leaf length, leaflet trichomes, anther trichomes and leaflet length to width ratio were the main interspecific morphological differences. Phylogenetic analysis based on ITS sequences indicated that interspecific relationships within the I. szechuensis complex were not resolved, except for I. delavayi. We concluded that these eight species of the I. szechuensis complex might be undergoing species differentiation caused by the complex habitats and geological history of the Hengduan Mountain region.
The Indigofera szechuensis complex contains nine species: I. szechuensis, I. pendula, I. hancockii, I. franchetii, I. delavayi, I. lenticellata, I. rigioclada, I. calcicola and I. heterantha. In this study, we conducted morphological and ITS variation analyses of 240 samples from 31 populations. Analysis of means showed that the nine species of the I. szechuensis complex mainly differed in leaflet size and inflorescence length. Principal component analysis indicated that the maximal leaf length, leaflet trichomes, anther trichomes and leaflet length to width ratio were the main interspecific morphological differences. Phylogenetic analysis based on ITS sequences indicated that interspecific relationships within the I. szechuensis complex were not resolved, except for I. delavayi. We concluded that these eight species of the I. szechuensis complex might be undergoing species differentiation caused by the complex habitats and geological history of the Hengduan Mountain region.
2015, 33(6): 734-743.
DOI: 10.11913/PSJ.2095-0837.2015.60734
Abstract：
Acer palmatum Thunb. (Aceraceae) is an important garden ornamental tree species in northern temperate regions. It is relatively difficult to classify by traditional methods due to frequent intraspecific hybridization and introgression. However, the emergence and development of DNA barcoding methods has provided an alternative approach to this issue. In this study, five candidate DNA noncoding regions (rpl16, psbA-trnH, trnL-trnF, rbcL and matK) from the chloroplast genome and internal transcribed spacer (ITS) region from the nuclear genome were used to distinguish eight taxa of A. palmatum. The identification efficiency estimated by PWG-distance and Tree-Building methods showed that single chloroplast DNA fragment (0% - 25%) or ITS fragment (12.5%) always showed low levels of species discrimination, while the combination of chloroplast DNA fragments (0% - 62.5%) and chloroplast DNA fragments plus ITS fragments (12.5% - 50%) had higher resolution for identifying A. palmatum. The highest discrimination rate of rpl16 + psbA-trnH + trnL-trnF reached 62.5%. Thus, we concluded that rpl16 + psbA-trnH + trnL-trnF could be considered as a potential barcode for taxa identification in A. palmatum.
Acer palmatum Thunb. (Aceraceae) is an important garden ornamental tree species in northern temperate regions. It is relatively difficult to classify by traditional methods due to frequent intraspecific hybridization and introgression. However, the emergence and development of DNA barcoding methods has provided an alternative approach to this issue. In this study, five candidate DNA noncoding regions (rpl16, psbA-trnH, trnL-trnF, rbcL and matK) from the chloroplast genome and internal transcribed spacer (ITS) region from the nuclear genome were used to distinguish eight taxa of A. palmatum. The identification efficiency estimated by PWG-distance and Tree-Building methods showed that single chloroplast DNA fragment (0% - 25%) or ITS fragment (12.5%) always showed low levels of species discrimination, while the combination of chloroplast DNA fragments (0% - 62.5%) and chloroplast DNA fragments plus ITS fragments (12.5% - 50%) had higher resolution for identifying A. palmatum. The highest discrimination rate of rpl16 + psbA-trnH + trnL-trnF reached 62.5%. Thus, we concluded that rpl16 + psbA-trnH + trnL-trnF could be considered as a potential barcode for taxa identification in A. palmatum.
2015, 33(6): 744-748.
DOI: 10.11913/PSJ.2095-0837.2015.60744
Abstract：
To explore the evolutionary characteristics of subgenus Soja plants, we compared anatomical structure differences among leaves of four soybean germplasm from Jilin Province by paraffin section. Results showed that there were significant differences in the anatomical structure of the four taxa of plant leaves within subgenus Soja. In accordance with the order of wild soybean to cultured soybean, the leaves and primary veins thickened, the number of epidermal hairs increased, vessel elements in the primary vein vascular bundle increased, abnormal vascular bundles appeared, the palisade tissue layers and CTR and SR values increased, and four cell layers evolved in the palisade tissue of cultured soybean. The evolutionary pattern (from lower to higher evolution) of the subgenus Soja plants determined from the structural characteristics was wild soybean → semi-wild soybean → semi-cultured soybean → cultured soybean.
To explore the evolutionary characteristics of subgenus Soja plants, we compared anatomical structure differences among leaves of four soybean germplasm from Jilin Province by paraffin section. Results showed that there were significant differences in the anatomical structure of the four taxa of plant leaves within subgenus Soja. In accordance with the order of wild soybean to cultured soybean, the leaves and primary veins thickened, the number of epidermal hairs increased, vessel elements in the primary vein vascular bundle increased, abnormal vascular bundles appeared, the palisade tissue layers and CTR and SR values increased, and four cell layers evolved in the palisade tissue of cultured soybean. The evolutionary pattern (from lower to higher evolution) of the subgenus Soja plants determined from the structural characteristics was wild soybean → semi-wild soybean → semi-cultured soybean → cultured soybean.
2015, 33(6): 749-756.
DOI: 10.11913/PSJ.2095-0837.2015.60749
Abstract：
To clarify the species composition and interspecific association of Acanthopanax senticosus communities in Beijing, we carried out a series of typical sampling investigations. Based on the 2 × 2 contingency table, we used variance ratio (VR), χ2-test, Pearson's correlation and Spearman's rank correlation to analyze the interspecific association among 27 dominant species in A. senticosus communities. Results showed that 27 dominant species were significantly positively correlated, indicating a relatively stable succession status in the communities. The χ2-test, Pearson's correlation and Spearman's rank correlation analyses among the 351 species-pairs of the 27 dominant species showed that 191, 112 and 170 species-pairs were positively correlated, 160, 239 and 181 species-pairs were negatively correlated, and the positive and negative ratios were 1.19, 0.47 and 0.94, respectively. According to the species adaptations to the environment and the leading ecological factors, in combination with principal components analysis, the 27 dominant species were divided into four ecological species groups. The results showed high interspecific association among the A. senticosus communities. The communities also showed relative stability in species composition and development of community structure.
To clarify the species composition and interspecific association of Acanthopanax senticosus communities in Beijing, we carried out a series of typical sampling investigations. Based on the 2 × 2 contingency table, we used variance ratio (VR), χ2-test, Pearson's correlation and Spearman's rank correlation to analyze the interspecific association among 27 dominant species in A. senticosus communities. Results showed that 27 dominant species were significantly positively correlated, indicating a relatively stable succession status in the communities. The χ2-test, Pearson's correlation and Spearman's rank correlation analyses among the 351 species-pairs of the 27 dominant species showed that 191, 112 and 170 species-pairs were positively correlated, 160, 239 and 181 species-pairs were negatively correlated, and the positive and negative ratios were 1.19, 0.47 and 0.94, respectively. According to the species adaptations to the environment and the leading ecological factors, in combination with principal components analysis, the 27 dominant species were divided into four ecological species groups. The results showed high interspecific association among the A. senticosus communities. The communities also showed relative stability in species composition and development of community structure.
2015, 33(6): 757-765.
DOI: 10.11913/PSJ.2095-0837.2015.60757
Abstract：
Cornus officinalis is a common traditional medicinal material. In this study, we simulated the potential geographical distribution of C. officinalis, and classified its habitat suitability based on 21 environmental factors and loganin contents. Fuzzy mathematics and maximum entropy were used to determine membership function and weight of each evaluation factor. We used the spatial analyst module of ArcGIS 10 to simulate the potential distribution of suitable habitat for C. officinalis growth in the study area. Results showed that climatic factors were the most important, followed by soil and topography. In the 21 evaluation factors, topsoil USDA texture classification (TTEX) had the greatest weight, followed by precipitation of growth (PG), annual precipitation (AP) and precipitation seasonality (PS). Highly suitable areas accounted for 19.94% of the study area, and were mainly distributed in southeast Gansu, south Shaanxi and west Henan. These areas exhibited suitable temperature, humidity and sunlight for C. officinalis growth. The percentages of suitable, low suitable and unsuitable areas for C. officinalis were 11.85%, 16.31% and 51.90%, respectively. Thus, the evaluation model based on GIS and fuzzy mathematics was appropriate for the determining habitat suitability for C. officinalis in the Qinling region, and was also able to quantify the effect of different environmental factors on C. officinalis in different habitats. This study provides scientific evidence for the management, protection and artificial cultivation of C. officinalis.
Cornus officinalis is a common traditional medicinal material. In this study, we simulated the potential geographical distribution of C. officinalis, and classified its habitat suitability based on 21 environmental factors and loganin contents. Fuzzy mathematics and maximum entropy were used to determine membership function and weight of each evaluation factor. We used the spatial analyst module of ArcGIS 10 to simulate the potential distribution of suitable habitat for C. officinalis growth in the study area. Results showed that climatic factors were the most important, followed by soil and topography. In the 21 evaluation factors, topsoil USDA texture classification (TTEX) had the greatest weight, followed by precipitation of growth (PG), annual precipitation (AP) and precipitation seasonality (PS). Highly suitable areas accounted for 19.94% of the study area, and were mainly distributed in southeast Gansu, south Shaanxi and west Henan. These areas exhibited suitable temperature, humidity and sunlight for C. officinalis growth. The percentages of suitable, low suitable and unsuitable areas for C. officinalis were 11.85%, 16.31% and 51.90%, respectively. Thus, the evaluation model based on GIS and fuzzy mathematics was appropriate for the determining habitat suitability for C. officinalis in the Qinling region, and was also able to quantify the effect of different environmental factors on C. officinalis in different habitats. This study provides scientific evidence for the management, protection and artificial cultivation of C. officinalis.
2015, 33(6): 766-774.
DOI: 10.11913/PSJ.2095-0837.2015.60766
Abstract：
To understand the quality of the forest ecosystem in Hubei Dalaoling Provincial Nature Reserve in the Three Gorges area, we used remote sensing satellite image data combined with field survey and available material to conduct a comparative study of changes in above-ground biomass (AGB), leaf area index (LAI) and net primary productivity (NPP) from 2000 to 2010. Results showed that:(1) AGB decreased over the 10 years, but the decline was very small, indicating that the vegetation structure of the Dalaoling forest ecosystem is relatively stable. However, further management mechanisms are still required to reduce human disturbance; (2) According to annual average LAI, medium(1.6 - 2.2) and relatively high level LAI(1.6 - 2.8) accounted for the major proportion of LAI, and the annual average LAI between 1.6 - 2.8 accounted for more than 90% of total area and showed an increasing trend, suggesting that vegetation is vigorous and growing well; (3) Total NPP increased slowly over the 10 years, from 4.99 × 1010 gC in 2000 to 5.07 × 1010 gC in 2010. The forest ecosystem has rich forest types, strong heterogeneity and high production capacity. Comprehensive analysis suggested that the forest ecosystem quality in Dalaoling Nature Reserve is generally good and has maintained good stability over the last 10 years, which is a reflection of conservation and protection measures.
To understand the quality of the forest ecosystem in Hubei Dalaoling Provincial Nature Reserve in the Three Gorges area, we used remote sensing satellite image data combined with field survey and available material to conduct a comparative study of changes in above-ground biomass (AGB), leaf area index (LAI) and net primary productivity (NPP) from 2000 to 2010. Results showed that:(1) AGB decreased over the 10 years, but the decline was very small, indicating that the vegetation structure of the Dalaoling forest ecosystem is relatively stable. However, further management mechanisms are still required to reduce human disturbance; (2) According to annual average LAI, medium(1.6 - 2.2) and relatively high level LAI(1.6 - 2.8) accounted for the major proportion of LAI, and the annual average LAI between 1.6 - 2.8 accounted for more than 90% of total area and showed an increasing trend, suggesting that vegetation is vigorous and growing well; (3) Total NPP increased slowly over the 10 years, from 4.99 × 1010 gC in 2000 to 5.07 × 1010 gC in 2010. The forest ecosystem has rich forest types, strong heterogeneity and high production capacity. Comprehensive analysis suggested that the forest ecosystem quality in Dalaoling Nature Reserve is generally good and has maintained good stability over the last 10 years, which is a reflection of conservation and protection measures.
2015, 33(6): 775-783.
DOI: 10.11913/PSJ.2095-0837.2015.60775
Abstract：
Thirteen typical wetland sites located between Yumenkou and the Fenhe River estuary in the middle reaches of the Yellow River were investigated, with the taxonomic index used to measure species diversity. Results showed that a total of 75 species, belonging to 61 genera, 23 families, 18 orders, three classes and two phyla were recorded from the 13 sites. At the phylum level, 73 species were mainly distributed in Angiospermae. At the class level, 57 species were mainly distributed in Dicotyledons. At the family level, 36 species were mainly distributed in Leguminosae, Compositae and Gramineae. At the genus level, 12 species were mainly distributed in Chenopodium, Lespedeza, Artemisi and Typha. Annual or biennial plants were the most abundant, closely followed by chamaephytes, hemicryptophytes and geophytes, and the life-form spectra reflected the hot rainy summers and cold dry winters of the middle reaches of the Yellow River. Plant species diversity was studied using average taxonomic distinctness (Δ + ) and variation in taxonomic distinctness (Λ + ), and the expected values of Δ + and Λ + were 84.25 and 425.43, respectively. Using bivariate analysis to evaluate Δ + and Λ + together showed that the expected value of plot S12 located at the Fenhe River estuary was the lowest, while the expected values of plots S8, S9 and S10 were higher, showing that the taxonomic diversity index of species was larger and the distribution of species was more uniform in S12 than that found in S8, S9 and S10. Pearson's test results showed that Δ + ,Λ + and the Shannon-Wiener, Pielou, Simpson and Patrick indices were not correlated (P > 0.05).
Thirteen typical wetland sites located between Yumenkou and the Fenhe River estuary in the middle reaches of the Yellow River were investigated, with the taxonomic index used to measure species diversity. Results showed that a total of 75 species, belonging to 61 genera, 23 families, 18 orders, three classes and two phyla were recorded from the 13 sites. At the phylum level, 73 species were mainly distributed in Angiospermae. At the class level, 57 species were mainly distributed in Dicotyledons. At the family level, 36 species were mainly distributed in Leguminosae, Compositae and Gramineae. At the genus level, 12 species were mainly distributed in Chenopodium, Lespedeza, Artemisi and Typha. Annual or biennial plants were the most abundant, closely followed by chamaephytes, hemicryptophytes and geophytes, and the life-form spectra reflected the hot rainy summers and cold dry winters of the middle reaches of the Yellow River. Plant species diversity was studied using average taxonomic distinctness (Δ + ) and variation in taxonomic distinctness (Λ + ), and the expected values of Δ + and Λ + were 84.25 and 425.43, respectively. Using bivariate analysis to evaluate Δ + and Λ + together showed that the expected value of plot S12 located at the Fenhe River estuary was the lowest, while the expected values of plots S8, S9 and S10 were higher, showing that the taxonomic diversity index of species was larger and the distribution of species was more uniform in S12 than that found in S8, S9 and S10. Pearson's test results showed that Δ + ,Λ + and the Shannon-Wiener, Pielou, Simpson and Patrick indices were not correlated (P > 0.05).
2015, 33(6): 784-791.
DOI: 10.11913/PSJ.2095-0837.2015.60784
Abstract：
Yanqi Basin is located in the middle of the Tianshan Mountains in Xinjiang, China. In terms of geographical division, the vegetation in this region belongs to the warm temperate shrub and subshrub desert area of Xinjiang. The unique natural geographical location and ecological environment of this region have led to abundant plant species. Studies on the distribution and diversity of the flora in Yanqi Basin are very important for the use, sustainable development and protection of plants in this region. Based on field studies and relevant literature, the diversity and flora of seed plants in Yanqi Basin were systematically analyzed. Results showed there were approximately 1035 species of seed plants belonging to 80 families and 373 genera in Yanqi Basin. Among these, 38 species were endemic to this region, accounting for 14.18% of total endemic species in Xinjiang. The 80 seed plant families could be divided into six types and seven subtypes. North temperate elements (22 families) were dominant in family floristic composition, accounting for 57.89% of total non-cosmopolitan families. In terms of the floristic geographical distribution type, 373 genera of seed plants could be divided into 12 types and 17 subtypes, with temperate elements (197 genera) accounting for 62.54% of total non-cosmopolitan genera. Herbaceous seed plants (901 in total) were the dominant type in Yanqi Basin, accounting for 87.05% of total seed plant species in this region. There were 110 shrub species (10.63%), 17 tree species (1.64%) and seven vine species (0.68%). In terms of the ecological types of seed plants in Yanqi Basin, there were 676 mesad species, 191 siccocolous species, 123 hygrophyte species and 45 aquatic species, accounting for 65.31%, 18.45%, 11.88% and 4.35% of total seed plants in this region, respectively.
Yanqi Basin is located in the middle of the Tianshan Mountains in Xinjiang, China. In terms of geographical division, the vegetation in this region belongs to the warm temperate shrub and subshrub desert area of Xinjiang. The unique natural geographical location and ecological environment of this region have led to abundant plant species. Studies on the distribution and diversity of the flora in Yanqi Basin are very important for the use, sustainable development and protection of plants in this region. Based on field studies and relevant literature, the diversity and flora of seed plants in Yanqi Basin were systematically analyzed. Results showed there were approximately 1035 species of seed plants belonging to 80 families and 373 genera in Yanqi Basin. Among these, 38 species were endemic to this region, accounting for 14.18% of total endemic species in Xinjiang. The 80 seed plant families could be divided into six types and seven subtypes. North temperate elements (22 families) were dominant in family floristic composition, accounting for 57.89% of total non-cosmopolitan families. In terms of the floristic geographical distribution type, 373 genera of seed plants could be divided into 12 types and 17 subtypes, with temperate elements (197 genera) accounting for 62.54% of total non-cosmopolitan genera. Herbaceous seed plants (901 in total) were the dominant type in Yanqi Basin, accounting for 87.05% of total seed plant species in this region. There were 110 shrub species (10.63%), 17 tree species (1.64%) and seven vine species (0.68%). In terms of the ecological types of seed plants in Yanqi Basin, there were 676 mesad species, 191 siccocolous species, 123 hygrophyte species and 45 aquatic species, accounting for 65.31%, 18.45%, 11.88% and 4.35% of total seed plants in this region, respectively.
2015, 33(6): 792-800.
DOI: 10.11913/PSJ.2095-0837.2015.60792
Abstract：
Five soil physicochemical indexes, including edaphic pH, edaphic salinity and soil nutrient values, were determined in seven Kandelia obovata populations located in the Futian Mangrove Nature Reserve of Shenzhen Bay. The morphological features of the secondary xylem of K. obovata populations corresponding to soil sampling, which represented different habitats, were surveyed by light microscopy (LM), scanning electron microscopy (SEM), laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM). Variations in the quantitative wood anatomical features of the seven K. obovata populations were assessed in detail. Relationships between soil physicochemical variables and quantitative wood anatomical features were analyzed statistically. Some specialized wood structures in K. obovata growing in different habitats were observed, suggesting that they function to safely conduct water under high negative pressure and are adaptive to intertidal habitats. Their characteristics included some fibriform vessel elements and a few vasicentric tracheids; abundant micromorphological structures such as vestures and helical structures on vessel walls, and vestured pits and perforated plates. The relationship between soil physicochemical factors and quantitative anatomical features by stepwise regression analysis indicated that larger-scale vessel elements occurred with increasing soil Na + content and total salt quantity. Large scale vessel elements improved the water transportation efficiency, but depressed water transportation safety. Presumably, other wood anatomical features might ensure safe mechanisms for K. obovata under conditions of higher soil ion content and larger scale vessel elements, which both result in lower water transportation safety.
Five soil physicochemical indexes, including edaphic pH, edaphic salinity and soil nutrient values, were determined in seven Kandelia obovata populations located in the Futian Mangrove Nature Reserve of Shenzhen Bay. The morphological features of the secondary xylem of K. obovata populations corresponding to soil sampling, which represented different habitats, were surveyed by light microscopy (LM), scanning electron microscopy (SEM), laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM). Variations in the quantitative wood anatomical features of the seven K. obovata populations were assessed in detail. Relationships between soil physicochemical variables and quantitative wood anatomical features were analyzed statistically. Some specialized wood structures in K. obovata growing in different habitats were observed, suggesting that they function to safely conduct water under high negative pressure and are adaptive to intertidal habitats. Their characteristics included some fibriform vessel elements and a few vasicentric tracheids; abundant micromorphological structures such as vestures and helical structures on vessel walls, and vestured pits and perforated plates. The relationship between soil physicochemical factors and quantitative anatomical features by stepwise regression analysis indicated that larger-scale vessel elements occurred with increasing soil Na + content and total salt quantity. Large scale vessel elements improved the water transportation efficiency, but depressed water transportation safety. Presumably, other wood anatomical features might ensure safe mechanisms for K. obovata under conditions of higher soil ion content and larger scale vessel elements, which both result in lower water transportation safety.
2015, 33(6): 801-807.
DOI: 10.11913/PSJ.2095-0837.2015.60801
Abstract：
Nine SSR markers developed by a modified FIASCO (Fast Isolation by AFLP Sequences COntaining repeats) method were used to analyze the genetic diversity and differentiation of three Osmunda japonica Thunb. populations,including two wild populations from Lushan and Enshi and one cultured population from Enshi. A total of 47 alleles were detected in the three populations, with a mean NA(number of alleles) of 5.222. The observed heterozygosity and expected heterozygosity were 0.000-0.944 and 0.577-0.834, respectively. The Shannon index ranged from 0.962 to 1.860. Results suggested that the microsatellite loci were highly polymorphic. For each population, the average expected heterozygosity was higher than that of the observed heterozygosity, and the population inbreeding polymorphism coefficient was positive, indicating the existence of non-random mating. For the three populations, the wild population from Enshi harbored the most abundant genetic diversity, while the cultured population had the lowest. Low levels of genetic differentiation were found between the two wild populations (FST＝0.092), which was supported by AMOVA analysis.
Nine SSR markers developed by a modified FIASCO (Fast Isolation by AFLP Sequences COntaining repeats) method were used to analyze the genetic diversity and differentiation of three Osmunda japonica Thunb. populations,including two wild populations from Lushan and Enshi and one cultured population from Enshi. A total of 47 alleles were detected in the three populations, with a mean NA(number of alleles) of 5.222. The observed heterozygosity and expected heterozygosity were 0.000-0.944 and 0.577-0.834, respectively. The Shannon index ranged from 0.962 to 1.860. Results suggested that the microsatellite loci were highly polymorphic. For each population, the average expected heterozygosity was higher than that of the observed heterozygosity, and the population inbreeding polymorphism coefficient was positive, indicating the existence of non-random mating. For the three populations, the wild population from Enshi harbored the most abundant genetic diversity, while the cultured population had the lowest. Low levels of genetic differentiation were found between the two wild populations (FST＝0.092), which was supported by AMOVA analysis.
2015, 33(6): 808-818.
DOI: 10.11913/PSJ.2095-0837.2015.60808
Abstract：
Three MYB genes, including CmMYB15, PtMYB15 and ClMYB15, were cloned from seedlings of pomelo (Citrus maxima (Burm.) Merr.), trifoliate orange (Poncirus trifoliata (L.) Raf.) and lemon (Citrus limon (L.) Burm.f.), respectively, by in silico and reverse transcription PCR approaches. Results showed that the full length cDNA sequences of the three genes were 994, 992 and 988 bp, and encoded 267, 266 and 265 amino acids, respectively. The N-terminal of the three novel proteins contained two series of incomplete repeat MYB DNA-binding domains, suggesting that the three genes belonged to the R2R3 subclass of the MYB family. Moreover, the expression patterns of these genes were analyzed by real-time quantitative PCR (qRT-PCR) under the stress of ABA, drought, cold and salt.Results indicated that the expressions of the three MYB15 genes were induced by all stress treatments. However, their expression levels after stress differed among the citrus species.The results of this paper suggested that CmMYB15, PtMYB15 and ClMYB15 were members of the MYB gene family, and might play important roles in citrus in response to abiotic stress.
Three MYB genes, including CmMYB15, PtMYB15 and ClMYB15, were cloned from seedlings of pomelo (Citrus maxima (Burm.) Merr.), trifoliate orange (Poncirus trifoliata (L.) Raf.) and lemon (Citrus limon (L.) Burm.f.), respectively, by in silico and reverse transcription PCR approaches. Results showed that the full length cDNA sequences of the three genes were 994, 992 and 988 bp, and encoded 267, 266 and 265 amino acids, respectively. The N-terminal of the three novel proteins contained two series of incomplete repeat MYB DNA-binding domains, suggesting that the three genes belonged to the R2R3 subclass of the MYB family. Moreover, the expression patterns of these genes were analyzed by real-time quantitative PCR (qRT-PCR) under the stress of ABA, drought, cold and salt.Results indicated that the expressions of the three MYB15 genes were induced by all stress treatments. However, their expression levels after stress differed among the citrus species.The results of this paper suggested that CmMYB15, PtMYB15 and ClMYB15 were members of the MYB gene family, and might play important roles in citrus in response to abiotic stress.
2015, 33(6): 819-828.
DOI: 10.11913/PSJ.2095-0837.2015.60819
Abstract：
The utility of artificial microRNA (amiRNA) to induce specific gene silencing has been reported in many plant species, but silencing efficiency of differently designed amiRNA constructs in transgenic plants is less predictable. Thus, pre-validation of the silencing efficiency of designed amiRNA constructs is indispensable. In this study, to target the mRNA of SmPAP1, a R2R3-MYB transcription factor gene of Salvia miltiorrhiza, two amiRNAs were designed using WMD3 (Web MicroRNA Designer), designated as amiRNA1-SmPAP1 and amiRNA2-SmPAP1, respectively. The transient co-expressions of the two amiRNAs constructs combined with the 35S∶SmPAP1 plant over-expression vector were subsequently examined by Agrobacterium-mediated transformation into tobacco leaf cells, respectively. Results showed that the expression level of amiRNA2 was almost twice that of amiRNA1, and the silencing strength of SmPAP1 by amiRNA2 was 2.5 times higher than that by amiRNA1. The significant negative correlation between amiRNA abundance and expression level of SmPAP1 at both the mRNA and protein level was observed in the transient agro-infiltration assays. Therefore, the assay for the transient expression of amiRNA in tobacco leaf cells can rapidly and effectively pre-validate silencing efficiency of diverse designed amiRNAs, and provide an important reference for subsequent genetic transformation in plants.
The utility of artificial microRNA (amiRNA) to induce specific gene silencing has been reported in many plant species, but silencing efficiency of differently designed amiRNA constructs in transgenic plants is less predictable. Thus, pre-validation of the silencing efficiency of designed amiRNA constructs is indispensable. In this study, to target the mRNA of SmPAP1, a R2R3-MYB transcription factor gene of Salvia miltiorrhiza, two amiRNAs were designed using WMD3 (Web MicroRNA Designer), designated as amiRNA1-SmPAP1 and amiRNA2-SmPAP1, respectively. The transient co-expressions of the two amiRNAs constructs combined with the 35S∶SmPAP1 plant over-expression vector were subsequently examined by Agrobacterium-mediated transformation into tobacco leaf cells, respectively. Results showed that the expression level of amiRNA2 was almost twice that of amiRNA1, and the silencing strength of SmPAP1 by amiRNA2 was 2.5 times higher than that by amiRNA1. The significant negative correlation between amiRNA abundance and expression level of SmPAP1 at both the mRNA and protein level was observed in the transient agro-infiltration assays. Therefore, the assay for the transient expression of amiRNA in tobacco leaf cells can rapidly and effectively pre-validate silencing efficiency of diverse designed amiRNAs, and provide an important reference for subsequent genetic transformation in plants.
2015, 33(6): 829-839.
DOI: 10.11913/PSJ.2095-0837.2015.60829
Abstract：
To breed high-yield buckwheat varieties with thin shells, the agronomic traits of 180 tartary buckwheat accessions were evaluated using statistical methods such as simple and partial correlation analysis and path analysis. Results showed that the variation coefficients of eight main agronomic traits ranged from 8.10% to 39.40%. Simple correlation analysis indicated that grain weight per plant (GW) was positively correlated with grain number per plant (GN) and number of primary branches (PBN). Partial correlation analysis showed that GW was positively correlated with GN and 1000-grain weight (TGW). Multiple stepwise regression and path analysis indicated that GN and TGW were the main factors affecting GW. Cluster analysis showed that the 180 tartary buckwheat accessions were classified into five groups, with 47 germplasm resources, primarily found in group Ⅲ, exhibiting excellent agronomic traits, including good stem branching capacity and high GN, GW and RGY. Therefore, 47 germplasm resources in group Ⅲ are suitable as tartary buckwheat breeding material and provide a basis for shell breeding with increased rice grain weight per plant (RGY) and milled rice rate (MR).
To breed high-yield buckwheat varieties with thin shells, the agronomic traits of 180 tartary buckwheat accessions were evaluated using statistical methods such as simple and partial correlation analysis and path analysis. Results showed that the variation coefficients of eight main agronomic traits ranged from 8.10% to 39.40%. Simple correlation analysis indicated that grain weight per plant (GW) was positively correlated with grain number per plant (GN) and number of primary branches (PBN). Partial correlation analysis showed that GW was positively correlated with GN and 1000-grain weight (TGW). Multiple stepwise regression and path analysis indicated that GN and TGW were the main factors affecting GW. Cluster analysis showed that the 180 tartary buckwheat accessions were classified into five groups, with 47 germplasm resources, primarily found in group Ⅲ, exhibiting excellent agronomic traits, including good stem branching capacity and high GN, GW and RGY. Therefore, 47 germplasm resources in group Ⅲ are suitable as tartary buckwheat breeding material and provide a basis for shell breeding with increased rice grain weight per plant (RGY) and milled rice rate (MR).
2015, 33(6): 840-846.
DOI: 10.11913/PSJ.2095-0837.2015.60840
Abstract：
Sedum hybridum presents high drought resistance. In this study, the physiological indexes of S. hybridum cutting seedlings were investigated in the 60 days of drought stress, including leaf relative water content, malondialdehyde (MDA) content, cell damage rate, photosynthetic parameters (net photosynthetic rate, stomatal conductance and transpiration rate), fluorescence parameters (Fv/Fm, qP, PHiPS2), malic acid content and phosphoeno-lpyruvate carboxylase (PEPCase) activity. Results showed that drought stress led to a decrease in leaf relative water content, photosynthetic parameters and fluorescence parameters, and an increase in cell damage rate and MDA content. Within the first 30 days of drought stress, the physiological indexes exhibited small amplitude variation. After 40 days of stress, the variation amplitude of physiological indexes increased rapidly. In the following experiments, malic acid content and PEPCase activity increased significantly, demonstrating that the C3 pathway was weakened and crassulacean acid metabolism (CAM) pathway was stimulated, which was involved in the stress response of S. hybridum to enhance drought resistance. After 60 days, stress exceeded the tolerance range of S. hybridum plants, leading to serious damage and gradual death. Our results showed that S.hybridum cuttings exhibited strong drought tolerance physiologically, and possessed the characteristics of a facultative CAM plant. Activation of the CAM pathway enhanced drought tolerance, which was an important mechanism of S.hybridum.
Sedum hybridum presents high drought resistance. In this study, the physiological indexes of S. hybridum cutting seedlings were investigated in the 60 days of drought stress, including leaf relative water content, malondialdehyde (MDA) content, cell damage rate, photosynthetic parameters (net photosynthetic rate, stomatal conductance and transpiration rate), fluorescence parameters (Fv/Fm, qP, PHiPS2), malic acid content and phosphoeno-lpyruvate carboxylase (PEPCase) activity. Results showed that drought stress led to a decrease in leaf relative water content, photosynthetic parameters and fluorescence parameters, and an increase in cell damage rate and MDA content. Within the first 30 days of drought stress, the physiological indexes exhibited small amplitude variation. After 40 days of stress, the variation amplitude of physiological indexes increased rapidly. In the following experiments, malic acid content and PEPCase activity increased significantly, demonstrating that the C3 pathway was weakened and crassulacean acid metabolism (CAM) pathway was stimulated, which was involved in the stress response of S. hybridum to enhance drought resistance. After 60 days, stress exceeded the tolerance range of S. hybridum plants, leading to serious damage and gradual death. Our results showed that S.hybridum cuttings exhibited strong drought tolerance physiologically, and possessed the characteristics of a facultative CAM plant. Activation of the CAM pathway enhanced drought tolerance, which was an important mechanism of S.hybridum.
2015, 33(6): 847-854.
DOI: 10.11913/PSJ.2095-0837.2015.60847
Abstract：
To develop co-dominant microsatellite molecular markers (SSRs) for studying conservation genetics of the giant lobelia endemic to east Africa, we sequenced the genome of the giant lobelia, Lobelia deckenii, using next-generation high-throughput sequencing technology. Using the MISA program, we acquired a total of 58966 SSRs, from which we designed 3558 SSR primer pairs using Primer software. We selected 40 primer pairs at random to evaluate their application across six individuals from three L.deckenii populations (two individuals per population). Thirty-two markers were successfully amplified, yielding clear and discernible bands. Using 24 L.deckenii individuals from the Mountain Kenya population, we tested the polymorphism of the 32 SSR markers and found that 14 were polymorphic. Using these 14 polymorphic SSR markers, we detected a total of 86 alleles. The number of alleles per locus ranged from four to nine. Observed heterozygosity (Ho) and expected value (He) per locus varied from 0.000 to 1.000 and 0.625 to 0.854, respectively. Our results indicated that development of SSR markers from genomic data by high-throughput sequencing in the giant lobelia was valuable and effective. These newly generated SSR markers will provide novel tools for studying genetic diversity, population genetic structure and conservation biology of giant lobelias in east Africa.
To develop co-dominant microsatellite molecular markers (SSRs) for studying conservation genetics of the giant lobelia endemic to east Africa, we sequenced the genome of the giant lobelia, Lobelia deckenii, using next-generation high-throughput sequencing technology. Using the MISA program, we acquired a total of 58966 SSRs, from which we designed 3558 SSR primer pairs using Primer software. We selected 40 primer pairs at random to evaluate their application across six individuals from three L.deckenii populations (two individuals per population). Thirty-two markers were successfully amplified, yielding clear and discernible bands. Using 24 L.deckenii individuals from the Mountain Kenya population, we tested the polymorphism of the 32 SSR markers and found that 14 were polymorphic. Using these 14 polymorphic SSR markers, we detected a total of 86 alleles. The number of alleles per locus ranged from four to nine. Observed heterozygosity (Ho) and expected value (He) per locus varied from 0.000 to 1.000 and 0.625 to 0.854, respectively. Our results indicated that development of SSR markers from genomic data by high-throughput sequencing in the giant lobelia was valuable and effective. These newly generated SSR markers will provide novel tools for studying genetic diversity, population genetic structure and conservation biology of giant lobelias in east Africa.
2015, 33(6): 855-860.
DOI: 10.11913/PSJ.2095-0837.2015.60855
Abstract：
Eomecon chionantha is a monotypic species endemic to subtropical China. In this study, 13 polymorphic microsatellite loci were developed from the genome of E. chionantha by magnetic bead enrichment, with biotin-labelled (AG)15 and (AC)15 probes. These loci were successfully amplified and displayed polymorphism. The polymorphism of each locus was screened among 24 individuals from four wild populations. Results showed that the number of alleles per locus varied from two to seven, and the observed and expected heterozygosity ranged from 0.125 to 0.792 and from 0.299 to 0.691, respectively.These SSR markers will provide tools for future studies on the genetic diversity of E. chionantha populations to help clarify current geographical distribution, and contribute to the conservation and utilization of wild resources of E. chionantha in subtropical China.
Eomecon chionantha is a monotypic species endemic to subtropical China. In this study, 13 polymorphic microsatellite loci were developed from the genome of E. chionantha by magnetic bead enrichment, with biotin-labelled (AG)15 and (AC)15 probes. These loci were successfully amplified and displayed polymorphism. The polymorphism of each locus was screened among 24 individuals from four wild populations. Results showed that the number of alleles per locus varied from two to seven, and the observed and expected heterozygosity ranged from 0.125 to 0.792 and from 0.299 to 0.691, respectively.These SSR markers will provide tools for future studies on the genetic diversity of E. chionantha populations to help clarify current geographical distribution, and contribute to the conservation and utilization of wild resources of E. chionantha in subtropical China.
2015, 33(6): 861-866.
DOI: 10.11913/PSJ.2095-0837.2015.60861
Abstract：
To simultaneously determine the contents of six flavonoids (rutin, hyperoside, astragalin, quercetin, kaempferol and isorhamnetin) in lotus leaves and related tea products, eight lotus leaf samples from different companies were detected by HPLC. The prepared samples were separated by Agilent TC-C18(2) (150 mm × 4.6 mm, 5 μm) at 25℃ with a step linear gradient using 0.5% formic acid-water (A) and 0.1% formic acid-acetonitrile (B) at a flow rate of 1.0 mL/min. The detection wavelength was 360 nm. Results showed that the concentration ranges of rutin, hyperoside, astragalin, quercetin, kaempferide and isorhamnetin were 1.6-160, 1.8-180, 2.16-216, 1.4-140, 2.12-212 and 1.6-160 μg/mL, respectively. Between these ranges, the linearity of the six flavonoids were well-presented (R2 > 0.9992) in a certain concentration range. The RSD values for the stability, repeatability, intra-day and inter-day precisions and recovery rates were all less than 2%. Eight lotus leaf samples from different companies were detected by the above method. The content of quercetin was the highest among the six flavonoids, and was highest in Batch No. 130802 from Company G. The method used in this study accurately detected the contents of six flavonoids in lotus leaves and tea products, and provided an effective way in which to determine the functional components and quality of lotus leaf products.
To simultaneously determine the contents of six flavonoids (rutin, hyperoside, astragalin, quercetin, kaempferol and isorhamnetin) in lotus leaves and related tea products, eight lotus leaf samples from different companies were detected by HPLC. The prepared samples were separated by Agilent TC-C18(2) (150 mm × 4.6 mm, 5 μm) at 25℃ with a step linear gradient using 0.5% formic acid-water (A) and 0.1% formic acid-acetonitrile (B) at a flow rate of 1.0 mL/min. The detection wavelength was 360 nm. Results showed that the concentration ranges of rutin, hyperoside, astragalin, quercetin, kaempferide and isorhamnetin were 1.6-160, 1.8-180, 2.16-216, 1.4-140, 2.12-212 and 1.6-160 μg/mL, respectively. Between these ranges, the linearity of the six flavonoids were well-presented (R2 > 0.9992) in a certain concentration range. The RSD values for the stability, repeatability, intra-day and inter-day precisions and recovery rates were all less than 2%. Eight lotus leaf samples from different companies were detected by the above method. The content of quercetin was the highest among the six flavonoids, and was highest in Batch No. 130802 from Company G. The method used in this study accurately detected the contents of six flavonoids in lotus leaves and tea products, and provided an effective way in which to determine the functional components and quality of lotus leaf products.
2015, 33(6): 867-872.
DOI: 10.11913/PSJ.2095-0837.2015.60867
Abstract：
An amplification cultivation system using a stirred tank bioreactor was established to obtain optimal conditions for licorice cell cultivation. The reactor operation strategy was optimized using the BP neural network coupling genetic algorithm, cell biomass accumulation net growth index, and data from single factor and orthogonal experiments. Results showed that an inoculum of 6.4%, shaking speed of 89 r/min and aeration rate of 0.1 vvm were the optimal culture conditions for Glycyrrhiza uralensis Fisch cells in the bioreactor. Coupling genetic algorithm optimization based on the neural network was compared with the traditional orthogonal experiments, which showed that cell biomass accumulation increased by 6.9%.
An amplification cultivation system using a stirred tank bioreactor was established to obtain optimal conditions for licorice cell cultivation. The reactor operation strategy was optimized using the BP neural network coupling genetic algorithm, cell biomass accumulation net growth index, and data from single factor and orthogonal experiments. Results showed that an inoculum of 6.4%, shaking speed of 89 r/min and aeration rate of 0.1 vvm were the optimal culture conditions for Glycyrrhiza uralensis Fisch cells in the bioreactor. Coupling genetic algorithm optimization based on the neural network was compared with the traditional orthogonal experiments, which showed that cell biomass accumulation increased by 6.9%.
