2017 Vol. 35 No. 1
2017, 35(1): 1-12.
DOI: 10.11913/PSJ.2095-0837.2017.10001
Abstract：
We examined the floral biology, mating system, flower color change, and pollination process of Lonicera chrysantha Turcz., L. japonica Thunb., L. ferdinandii Franch. and L. maackii (Rupr.) Maxim. from the Qinling mountains via field observation, artificial pollination experiments, and artificial experimental patches. Pollen limitations and some differences in single-flower flowering and floral traits were observed among the species, which were all self-incompatible plants. Except for L. ferdinandii, all species changed their corolla color with decreasing pollen/nectar rewards and lost both male and female reproductive abilities. The nectar reward in L. ferdinandii did not alter significantly, and it retained strong female reproductive function. The retention of post-color change flowers might be a reproductive strategy of plants, in which an increase in floral display enhanced attractiveness to pollinators. The artificial control experiments showed that most pollinators preferred to visit the white flowers (pre-change flowers), and the amount of reward and number of yellow flowers (post-change flowers) significantly impacted pollinators' access frequency. That is, access frequency decreased with nectar reduction or increase in yellow flowers. These results indicate that flower color changes might increase plant attractiveness to distant pollinators, or have a certain influence on nearby pollinators. The post-change flowers might play a role in signaling to pollinators during their approach that the reward of nectar or pollen had changed, thus re-directing the insects to the sufficiently rewarded white flowers of homophyletic or heterologous plants. This could improve both the foraging efficiency of pollinators and reduce the chance of geitonogamy, which has important implications for the Lonicera species and their pollinators. These results show the reaction of plants and pollinators to long-term mutual adaptation.
We examined the floral biology, mating system, flower color change, and pollination process of Lonicera chrysantha Turcz., L. japonica Thunb., L. ferdinandii Franch. and L. maackii (Rupr.) Maxim. from the Qinling mountains via field observation, artificial pollination experiments, and artificial experimental patches. Pollen limitations and some differences in single-flower flowering and floral traits were observed among the species, which were all self-incompatible plants. Except for L. ferdinandii, all species changed their corolla color with decreasing pollen/nectar rewards and lost both male and female reproductive abilities. The nectar reward in L. ferdinandii did not alter significantly, and it retained strong female reproductive function. The retention of post-color change flowers might be a reproductive strategy of plants, in which an increase in floral display enhanced attractiveness to pollinators. The artificial control experiments showed that most pollinators preferred to visit the white flowers (pre-change flowers), and the amount of reward and number of yellow flowers (post-change flowers) significantly impacted pollinators' access frequency. That is, access frequency decreased with nectar reduction or increase in yellow flowers. These results indicate that flower color changes might increase plant attractiveness to distant pollinators, or have a certain influence on nearby pollinators. The post-change flowers might play a role in signaling to pollinators during their approach that the reward of nectar or pollen had changed, thus re-directing the insects to the sufficiently rewarded white flowers of homophyletic or heterologous plants. This could improve both the foraging efficiency of pollinators and reduce the chance of geitonogamy, which has important implications for the Lonicera species and their pollinators. These results show the reaction of plants and pollinators to long-term mutual adaptation.
2017, 35(1): 13-20.
DOI: 10.11913/PSJ.2095-0837.2017.10013
Abstract：
Gynomonoecy is the mode of sex expression in which female and bisexual flowers occur on the same plant. To date, previous research has primarily focused on its occurrence in Asteraceae. There are two types of hermaphrodite flowers in Silene uniflora Roth., namely fertile and male sterile. As both hermaphrodite and functional female flowers occur, the sex system of S. uniflora is functional gynomonoecy. Fertile hermaphrodite flowers exhibit protandry and dichogamy. Their breeding system includes outcrossing and partial self-pollination. The seed setting rate through autogamy was 31.71%. Some flowers showed malformed stamens and pollen, resulting in reduced pollen output. More functional female flowers were found in the early or later flowering period. Functional gynomonoecious S. uniflora might be advan-tageous to reduce autogamy and interfere with male and female function to improve allogamy. This phylogenetic characteristic is beneficial to the mobility and flexibility of resource allocation.
Gynomonoecy is the mode of sex expression in which female and bisexual flowers occur on the same plant. To date, previous research has primarily focused on its occurrence in Asteraceae. There are two types of hermaphrodite flowers in Silene uniflora Roth., namely fertile and male sterile. As both hermaphrodite and functional female flowers occur, the sex system of S. uniflora is functional gynomonoecy. Fertile hermaphrodite flowers exhibit protandry and dichogamy. Their breeding system includes outcrossing and partial self-pollination. The seed setting rate through autogamy was 31.71%. Some flowers showed malformed stamens and pollen, resulting in reduced pollen output. More functional female flowers were found in the early or later flowering period. Functional gynomonoecious S. uniflora might be advan-tageous to reduce autogamy and interfere with male and female function to improve allogamy. This phylogenetic characteristic is beneficial to the mobility and flexibility of resource allocation.
2017, 35(1): 21-29.
DOI: 10.11913/PSJ.2095-0837.2017.10021
Abstract：
The micromorphological structures of twelve species of moss plants were observed from the No.1 glacier of the Tianshan Mountains by paraffin section and scanning electron microscopy (SEM). Results indicated that the type, size, distribution, degree of dry cell wall depression, and morphology and distribution of surface cuticles and pores of the leaf cells, middle ribs, cell walls and cell surfaces were significantly different in different bryophyte species. These micromorphological characteristics not only have great significance in the species classification of moss plants, but also reflect the survival strategy of plant leaves for retaining water and resisting cold, wind and strong light irradiation in severe environments. This study can provide an important scientific basis for studies on the ecological functions of bryophytes in extreme environments.
The micromorphological structures of twelve species of moss plants were observed from the No.1 glacier of the Tianshan Mountains by paraffin section and scanning electron microscopy (SEM). Results indicated that the type, size, distribution, degree of dry cell wall depression, and morphology and distribution of surface cuticles and pores of the leaf cells, middle ribs, cell walls and cell surfaces were significantly different in different bryophyte species. These micromorphological characteristics not only have great significance in the species classification of moss plants, but also reflect the survival strategy of plant leaves for retaining water and resisting cold, wind and strong light irradiation in severe environments. This study can provide an important scientific basis for studies on the ecological functions of bryophytes in extreme environments.
2017, 35(1): 30-38.
DOI: 10.11913/PSJ.2095-0837.2017.10030
Abstract：
The flora of Hebao Island in Guangdong province was analyzed systematically by field investigation and the composition and floristic characteristics of the vascular plants were determined. A total of 541 vascular plants belonging to 370 genera and 135 families were recorded, including 465 wild species and 36 cultivated species, among which 40 species belonging to 28 genera and 22 families were pteridophytes and 501 species belonging to 342 genera and 113 families were spermatophytes. At the genera level, the proportion of tropical elements was dominant and reached 87.80%. At the species level, 74 species endemic to China accounted for 15.91% of the non-cosmopolitan species. Four areal types, that is, pan-tropical, old-world tropical, tropical Asian to tropical Australasian Oceania and tropical Asian formed the main flora of Hebao Island. Compared with four other islands (Macao, Tung Ping Chau of Hong Kong, Zhoushan in Zhejiang province, and Chongming of Shanghai) along the southeast coast of China, the flora of Hebao Island showed higher tropical characteristics, and indicated a closer connection to Macao flora.
The flora of Hebao Island in Guangdong province was analyzed systematically by field investigation and the composition and floristic characteristics of the vascular plants were determined. A total of 541 vascular plants belonging to 370 genera and 135 families were recorded, including 465 wild species and 36 cultivated species, among which 40 species belonging to 28 genera and 22 families were pteridophytes and 501 species belonging to 342 genera and 113 families were spermatophytes. At the genera level, the proportion of tropical elements was dominant and reached 87.80%. At the species level, 74 species endemic to China accounted for 15.91% of the non-cosmopolitan species. Four areal types, that is, pan-tropical, old-world tropical, tropical Asian to tropical Australasian Oceania and tropical Asian formed the main flora of Hebao Island. Compared with four other islands (Macao, Tung Ping Chau of Hong Kong, Zhoushan in Zhejiang province, and Chongming of Shanghai) along the southeast coast of China, the flora of Hebao Island showed higher tropical characteristics, and indicated a closer connection to Macao flora.
2017, 35(1): 39-47.
DOI: 10.11913/PSJ.2095-0837.2017.10039
Abstract：
Corylus mandshurica was selected for study in the Dahe forest area in the Zhongtiao mountains, Mianshan, Xingtangsi, and Qiliyu forest areas in the Taiyue mountains, Jingangku forest area in the Wutai mountains, and Wangzhuangbao forest area in Hengshan of the Shanxi Province. Using six quadrats, the configuration and fractal dimension characteristics of C. mandshurica in different habitats were studied. Results showed that the overall bifurcation ratio and the ratio of branch diameter (RBD2:1, RBD3:2) in the Dahe forest area were higher than those in other areas. The stepwise bifurcation ratio exhibited the opposite trend as the overall bifurcation ratio, and the stepwise bifurcation ratio of C. mandshurica in the Wutai mountains was the highest. However, the branch angle of C. mandshurica showed significant differences in each studied area. The branch angle gradually decreased from the first-class to the third-class in the northern territories. The first-class branch angle of C. mandshurica in the Jingangku forest area was the highest. The order of C. mandshurica branch length was Jingangku > Wangzhuangbao > Qiliyu > Xingtangsi > Mianshan > Dahe, which exhibited a weakening trend from the first-class to the third-class. Fractal dimension was an important indicator, and clarified the complexity of plants. The greater the fractal dimension value, the stronger the plant occupied the space and the greater the potential use of space resources. The crown fractal dimension and bifurcation dimension of C. mandshurica were the highest in Jingangku. The crown structure was closely related to biomass. Leaf area, leaf biomass, and branch biomass from the side reflected the architectural characteristics of the plants. We analyzed the relationship among plant architecture, leaf area, and aboveground biomass. Leaf area and aboveground biomass of C. mandshurica gradually decreased from north to south of Shanxi Province. The average leaf area, leaf biomass, and branch biomass of C. mandshurica were the greatest in Jingangku. Results showed that the growth of C. mandshurica was the best in Jingangku compared with the other study areas, thus reflecting the area in which climate conditions were optimum for C. mandshurica.
Corylus mandshurica was selected for study in the Dahe forest area in the Zhongtiao mountains, Mianshan, Xingtangsi, and Qiliyu forest areas in the Taiyue mountains, Jingangku forest area in the Wutai mountains, and Wangzhuangbao forest area in Hengshan of the Shanxi Province. Using six quadrats, the configuration and fractal dimension characteristics of C. mandshurica in different habitats were studied. Results showed that the overall bifurcation ratio and the ratio of branch diameter (RBD2:1, RBD3:2) in the Dahe forest area were higher than those in other areas. The stepwise bifurcation ratio exhibited the opposite trend as the overall bifurcation ratio, and the stepwise bifurcation ratio of C. mandshurica in the Wutai mountains was the highest. However, the branch angle of C. mandshurica showed significant differences in each studied area. The branch angle gradually decreased from the first-class to the third-class in the northern territories. The first-class branch angle of C. mandshurica in the Jingangku forest area was the highest. The order of C. mandshurica branch length was Jingangku > Wangzhuangbao > Qiliyu > Xingtangsi > Mianshan > Dahe, which exhibited a weakening trend from the first-class to the third-class. Fractal dimension was an important indicator, and clarified the complexity of plants. The greater the fractal dimension value, the stronger the plant occupied the space and the greater the potential use of space resources. The crown fractal dimension and bifurcation dimension of C. mandshurica were the highest in Jingangku. The crown structure was closely related to biomass. Leaf area, leaf biomass, and branch biomass from the side reflected the architectural characteristics of the plants. We analyzed the relationship among plant architecture, leaf area, and aboveground biomass. Leaf area and aboveground biomass of C. mandshurica gradually decreased from north to south of Shanxi Province. The average leaf area, leaf biomass, and branch biomass of C. mandshurica were the greatest in Jingangku. Results showed that the growth of C. mandshurica was the best in Jingangku compared with the other study areas, thus reflecting the area in which climate conditions were optimum for C. mandshurica.
2017, 35(1): 48-55.
DOI: 10.11913/PSJ.2095-0837.2017.10048
Abstract：
CHRIS/PROBA is a multiple-angle sensor providing hyper-spectral data with 17 m×17 m spatial resolution that can be applied for data inversion of vegetation canopy structure parameters, such as tree height and leaf area index (LAI). We used a four-scale geometrical optics model to simulate anisotropy distribution regulation of the normalized difference vegetation index (NDVI) of a Pinus massoniana (Masson pine) forest canopy. By extracting the red and near infrared characteristic spectral bands from the 18 bands in CHRIS, a new multi-angle normalized hotspot-dark-spot difference vegetation index (NHDVI) was applied to the estimation of the LAI of Pinus massoniana forest using CHRIS data. The results showed that:(1) Compared with the NDVI and soil adjusted vegetation index (SAVI), NHDVI well integrated the spectral information and angle information with the ground measured LAI, and the coefficient of determination reached 0.7278; (2) The LAI was calculated by statistical regression of NHDVI-LAI. The correlation between the LAI and the measured values was 0.8272, significantly higher than that of SAVI, and the root mean square error (RMSE) was 0.1232. Thus, these findings indicate that angular information is important for improving the retrieval accuracy of LAI.
CHRIS/PROBA is a multiple-angle sensor providing hyper-spectral data with 17 m×17 m spatial resolution that can be applied for data inversion of vegetation canopy structure parameters, such as tree height and leaf area index (LAI). We used a four-scale geometrical optics model to simulate anisotropy distribution regulation of the normalized difference vegetation index (NDVI) of a Pinus massoniana (Masson pine) forest canopy. By extracting the red and near infrared characteristic spectral bands from the 18 bands in CHRIS, a new multi-angle normalized hotspot-dark-spot difference vegetation index (NHDVI) was applied to the estimation of the LAI of Pinus massoniana forest using CHRIS data. The results showed that:(1) Compared with the NDVI and soil adjusted vegetation index (SAVI), NHDVI well integrated the spectral information and angle information with the ground measured LAI, and the coefficient of determination reached 0.7278; (2) The LAI was calculated by statistical regression of NHDVI-LAI. The correlation between the LAI and the measured values was 0.8272, significantly higher than that of SAVI, and the root mean square error (RMSE) was 0.1232. Thus, these findings indicate that angular information is important for improving the retrieval accuracy of LAI.
Abstract：
Amur cork (Phellodendron amurense Rupr.) is listed as a second-class protected plant, and is found in small populations of scattered broad-leaved forests in the Beijing area. A total of 12 plots (20 m×20 m) were set up in Baihuashan, Songshan, and Wulingshan Nature Reserves in Beijing to understand the relationship between the distribution of P. amurense and environmental factors in Beijing and to promote population development. The CCA method was used to analyze the effects of different locations, and the relationship between the growth and distribution of P. amurense and 11 environmental factors such as altitude, slope, aspect, canopy density, soil pH, soil available N, and soil organic matter. Results showed that the first axis of the CCA ordination diagram mainly reflected changes in altitude, canopy density, and slope, whereas, the second axis mainly reflected changes in organic matter content, nitrogen content, pH value, and slope. Thus, altitude, soil available N, and soil organic matter are important environmental factors that influence Amur cork distribution, and areas with low altitude, low soil available N and high soil organic matter are suitable for its growth. Quantitative analysis of the influence of environmental factors on species distribution showed they had a good ability to explain P. amurense distribution (84.5%) and a good sorting effect, suggesting that the distribution of amur cork in the sample spots was strongly affected by the studied environmental factors. The plant community also showed a corresponding relationship with areas exhibiting less human interference. There was a significant correlation between environmental factors and species distribution (P=0.03), which strengthened the reliability of the results.
Amur cork (Phellodendron amurense Rupr.) is listed as a second-class protected plant, and is found in small populations of scattered broad-leaved forests in the Beijing area. A total of 12 plots (20 m×20 m) were set up in Baihuashan, Songshan, and Wulingshan Nature Reserves in Beijing to understand the relationship between the distribution of P. amurense and environmental factors in Beijing and to promote population development. The CCA method was used to analyze the effects of different locations, and the relationship between the growth and distribution of P. amurense and 11 environmental factors such as altitude, slope, aspect, canopy density, soil pH, soil available N, and soil organic matter. Results showed that the first axis of the CCA ordination diagram mainly reflected changes in altitude, canopy density, and slope, whereas, the second axis mainly reflected changes in organic matter content, nitrogen content, pH value, and slope. Thus, altitude, soil available N, and soil organic matter are important environmental factors that influence Amur cork distribution, and areas with low altitude, low soil available N and high soil organic matter are suitable for its growth. Quantitative analysis of the influence of environmental factors on species distribution showed they had a good ability to explain P. amurense distribution (84.5%) and a good sorting effect, suggesting that the distribution of amur cork in the sample spots was strongly affected by the studied environmental factors. The plant community also showed a corresponding relationship with areas exhibiting less human interference. There was a significant correlation between environmental factors and species distribution (P=0.03), which strengthened the reliability of the results.
2017, 35(1): 64-72.
DOI: 10.11913/PSJ.2095-0837.2017.10064
Abstract：
The CYP83B1 gene of Isatis indigotica Fort. was cloned and its expression patterns were analyzed. Results showed that the length of the IiCYP83B1 gene was 1652 bp, and included two exons and one intron. The full length cDNA of IiCYP83B1 was 1500 bp, encoding a protein of 499 amino acids. IiCYP83B1 was a hydrophobic protein located in the endoplasmic reticulum, without a transmembrane domain or signal peptide. Its secondary structure mainly included alpha helixes and irregular coils. Homologous comparison illustrated that IiCYP83B1 has close relationship with Raphanus sativus Linn., Brassica napus L., Brassica oleracea L., and Brassica rapa L. qRT-PCR analysis indicated that IiCYP83B1 was expressed in root, stem, flower, and fruit, and highly expressed in leaf. It was also highly expressed in the seedling, vegetative growth, and flowering stages, compared with the germination period. Moreover, IiCYP83B1 could be induced significantly by methyl jasmonate (MeJA) and glucose (Glu), but repressed by low temperature (4℃) and salicylic acid (SA). Results in this experiment provide reference for further functional study on IiCYP83B1.
The CYP83B1 gene of Isatis indigotica Fort. was cloned and its expression patterns were analyzed. Results showed that the length of the IiCYP83B1 gene was 1652 bp, and included two exons and one intron. The full length cDNA of IiCYP83B1 was 1500 bp, encoding a protein of 499 amino acids. IiCYP83B1 was a hydrophobic protein located in the endoplasmic reticulum, without a transmembrane domain or signal peptide. Its secondary structure mainly included alpha helixes and irregular coils. Homologous comparison illustrated that IiCYP83B1 has close relationship with Raphanus sativus Linn., Brassica napus L., Brassica oleracea L., and Brassica rapa L. qRT-PCR analysis indicated that IiCYP83B1 was expressed in root, stem, flower, and fruit, and highly expressed in leaf. It was also highly expressed in the seedling, vegetative growth, and flowering stages, compared with the germination period. Moreover, IiCYP83B1 could be induced significantly by methyl jasmonate (MeJA) and glucose (Glu), but repressed by low temperature (4℃) and salicylic acid (SA). Results in this experiment provide reference for further functional study on IiCYP83B1.
Abstract：
We used the second intron of the LEAFY gene to analyze the genetic diversity of Isoetes sinensis Palmer from China. In total, 105 samples were collected from seven populations. From these I. sinensis samples, 78 haplotypes were discovered, with a haplotype diversity of 0.989 and nucleotide diversity of 0.021. Results showed that genetic differentiation coefficient GST=0.283, NST=0.298, GST>NST, Nm=0.59; Mantel test, Rxy=-0.286, P (rxy-rand≥rxy-data)=0.370, and 72% of the total variation existed within populations. UPGMA cluster showed that the two high altitude populations had distant genetic relationships with the other five populations. The neutrality test, Tajima's D, Fu & Li's D* and F* tests were negative, and the mismatch distribution test based on a stable model was multimodal. According to the geographic location of I. sinensis, its genetic structure was related to the drainage, altitude, and process of hybrid polyploidization.
We used the second intron of the LEAFY gene to analyze the genetic diversity of Isoetes sinensis Palmer from China. In total, 105 samples were collected from seven populations. From these I. sinensis samples, 78 haplotypes were discovered, with a haplotype diversity of 0.989 and nucleotide diversity of 0.021. Results showed that genetic differentiation coefficient GST=0.283, NST=0.298, GST>NST, Nm=0.59; Mantel test, Rxy=-0.286, P (rxy-rand≥rxy-data)=0.370, and 72% of the total variation existed within populations. UPGMA cluster showed that the two high altitude populations had distant genetic relationships with the other five populations. The neutrality test, Tajima's D, Fu & Li's D* and F* tests were negative, and the mismatch distribution test based on a stable model was multimodal. According to the geographic location of I. sinensis, its genetic structure was related to the drainage, altitude, and process of hybrid polyploidization.
Abstract：
In this study, the interactions between MADS-box B transcription factors GLO1 and CsGLO2, and C transcription factor CsAG in Camellia sinensis L. in relation to flower development as well as their possible subcellular localizations were investigated using the yeast two-hybrid method and bimolecular fluorescence complementation (BiFC). In this study, five yeast expression vectors were constructed and the transcriptional activation activities of the three proteins were tested by yeast one-hybridization. The interactions among the three proteins were further analyzed by yeast two-hybrid assay. The results showed that the three proteins had no transcriptional activation activity, but interactions did occur among them. Six BiFC expression vectors were constructed and transformed into the leaf epidermal cells of tobacco (Nicotiana benthamiana L.) by pressure injection. The fluorescence signals were then observed by confocal laser scanning microscopy. The results showed that the three proteins could form homo- and heterodimers, and had specific patterns of interaction in the cytoplasm. This study could provide a theoretical basis for the inhibition of C. sinensis ‘flower and fruit present’ using molecular biology techniques.
In this study, the interactions between MADS-box B transcription factors GLO1 and CsGLO2, and C transcription factor CsAG in Camellia sinensis L. in relation to flower development as well as their possible subcellular localizations were investigated using the yeast two-hybrid method and bimolecular fluorescence complementation (BiFC). In this study, five yeast expression vectors were constructed and the transcriptional activation activities of the three proteins were tested by yeast one-hybridization. The interactions among the three proteins were further analyzed by yeast two-hybrid assay. The results showed that the three proteins had no transcriptional activation activity, but interactions did occur among them. Six BiFC expression vectors were constructed and transformed into the leaf epidermal cells of tobacco (Nicotiana benthamiana L.) by pressure injection. The fluorescence signals were then observed by confocal laser scanning microscopy. The results showed that the three proteins could form homo- and heterodimers, and had specific patterns of interaction in the cytoplasm. This study could provide a theoretical basis for the inhibition of C. sinensis ‘flower and fruit present’ using molecular biology techniques.
2017, 35(1): 87-92.
DOI: 10.11913/PSJ.2095-0837.2017.10087
Abstract：
The genetic characteristics of Hydrilla verticillata (L.f.) Royle were analyzed with chloroplast DNA (cpDNA) markers. Out of 18 candidate pairs, three effective molecular markers (trnL-trnF, trnH-psbA, RPL16) were screened, providing the molecular basis for further research. In total, 12 haplotypes were discovered in 40 samples of H. verticillata, with 135 mutation sites and haplotype diversity of 0.9064. Haplotype-4 was found in regions SXHZ and YY, which were geographically distant. In addition, 85.79% of total variation existed between populations. Through asexual reproduction, H. verticillata could carry out rapid expansion. Geographical separation and various environments between populations have likely resulted in low gene flow. In addition, the genetic structure of H. verticillata has been profoundly affected by founder effect and genetic drift.
The genetic characteristics of Hydrilla verticillata (L.f.) Royle were analyzed with chloroplast DNA (cpDNA) markers. Out of 18 candidate pairs, three effective molecular markers (trnL-trnF, trnH-psbA, RPL16) were screened, providing the molecular basis for further research. In total, 12 haplotypes were discovered in 40 samples of H. verticillata, with 135 mutation sites and haplotype diversity of 0.9064. Haplotype-4 was found in regions SXHZ and YY, which were geographically distant. In addition, 85.79% of total variation existed between populations. Through asexual reproduction, H. verticillata could carry out rapid expansion. Geographical separation and various environments between populations have likely resulted in low gene flow. In addition, the genetic structure of H. verticillata has been profoundly affected by founder effect and genetic drift.
Abstract：
The main factors that affect the determination of plant water potential are leaf sizes, shapes, fragmentation degree, sampling time, and sample storage; however, relative studies are very limited. In the present research, Dalbergia odorifera T. Chen individuals with similar maturity and strong pinnately compound leaves were used to study the above mentioned factors. The diurnal dynamic changes in leaf water potential were measured with the WP4C dewpoint potential meter every hour. Results showed that the most reasonable period for determination of leaf water potential was from 09:00 to 13:00. The leaf water potentials of leaves stored at 4℃ for 0, 0.5, 1, 2, and 3 h were measured, respectively. Results suggested that the best storage duration to measure leaf water potential was within 1 h after sampling. Our results also showed that leaf shapes, sizes, and fragmentation degrees had significant influences on water potential. Single leaf samples should completely cover the sample chamber of the instrument when leaf water potential is determined. Under our optimized conditions, the methods exhibited high accuracy, repeatability, and stability.
The main factors that affect the determination of plant water potential are leaf sizes, shapes, fragmentation degree, sampling time, and sample storage; however, relative studies are very limited. In the present research, Dalbergia odorifera T. Chen individuals with similar maturity and strong pinnately compound leaves were used to study the above mentioned factors. The diurnal dynamic changes in leaf water potential were measured with the WP4C dewpoint potential meter every hour. Results showed that the most reasonable period for determination of leaf water potential was from 09:00 to 13:00. The leaf water potentials of leaves stored at 4℃ for 0, 0.5, 1, 2, and 3 h were measured, respectively. Results suggested that the best storage duration to measure leaf water potential was within 1 h after sampling. Our results also showed that leaf shapes, sizes, and fragmentation degrees had significant influences on water potential. Single leaf samples should completely cover the sample chamber of the instrument when leaf water potential is determined. Under our optimized conditions, the methods exhibited high accuracy, repeatability, and stability.
Abstract：
To understand the relationship between endogenous hormone content during embryonic callus induction, somatic embryos were obtained by embryonic callus induction from loquat leaves. The content of four endogenous hormones, gibberellic acid (GA3), auxin (IAA), abscisic acid (ABA) and zeatin (ZT), were analyzed by high performance liquid chromatography (HPLC). The dynamic changes of these endogenous hormones in embryonic calli were then explored. Results suggested that the ratio of IAA/ZT in leaves had a positive effect on embryonic callus induction, whereas GA3/IAA had a negative effect. Low content of GA3 and high content of IAA and ABA were required for embryonic calli induction, and a high ratio of IAA/ZT was advantageous to their formation. The timely addition of exogenous hormones in the late period of subculture was helpful for maintaining the embryo. This research provides a theoretical direction for explant selection, extraneous hormone addition to calli subculture, and successive transfer time selection, as well as a foundation for efficiently obtaining embryonic materials and developing the study of gene transformation.
To understand the relationship between endogenous hormone content during embryonic callus induction, somatic embryos were obtained by embryonic callus induction from loquat leaves. The content of four endogenous hormones, gibberellic acid (GA3), auxin (IAA), abscisic acid (ABA) and zeatin (ZT), were analyzed by high performance liquid chromatography (HPLC). The dynamic changes of these endogenous hormones in embryonic calli were then explored. Results suggested that the ratio of IAA/ZT in leaves had a positive effect on embryonic callus induction, whereas GA3/IAA had a negative effect. Low content of GA3 and high content of IAA and ABA were required for embryonic calli induction, and a high ratio of IAA/ZT was advantageous to their formation. The timely addition of exogenous hormones in the late period of subculture was helpful for maintaining the embryo. This research provides a theoretical direction for explant selection, extraneous hormone addition to calli subculture, and successive transfer time selection, as well as a foundation for efficiently obtaining embryonic materials and developing the study of gene transformation.
2017, 35(1): 107-114.
DOI: 10.11913/PSJ.2095-0837.2017.10107
Abstract：
Volatile components and their contents in fresh Michelia martinii Levl. (MML) leaves in spring, summer, autumn and winter were analyzed by gas chromatography mass spectrometry (GC-MS). We identified 65 volatile compounds from the fresh leaf samples of MML in spring, summer, autumn and winter (peak values below 0.49 were neglected), which belonged to 26, 29, 31 and 32 components, respectively. In the fresh MML leaves, there were 14 common components, including tricyclene, α-pinene, camphene, sabinene, β-pinene, β-myrcene, α-phellandrene, d-limonene, eucalyptol, trans-β-ocimene, eucalyptol, ledol, eudesm-4 and β-linalool. In addition, α-pinene, camphene, β-pinene and linalool were common volatile components found in fresh leaves growing in all four seasons and in dry buds of MML. For essential oil, α-pinene, β-pinene, β-myrcene, β-linalool, linalool and myrcene had the highest contents in fresh leaves, indicating that MML leaves have health benefits and are suitable all year. Fresh leaves of MML in spring exhibited the highest rate of volatile oil extraction. This study on the differences and seasonal changes of volatile components in fresh MML leaves provides a scientific basis and guide for the seasonal selection of volatile oil extraction in MML and the construction of health care communities.
Volatile components and their contents in fresh Michelia martinii Levl. (MML) leaves in spring, summer, autumn and winter were analyzed by gas chromatography mass spectrometry (GC-MS). We identified 65 volatile compounds from the fresh leaf samples of MML in spring, summer, autumn and winter (peak values below 0.49 were neglected), which belonged to 26, 29, 31 and 32 components, respectively. In the fresh MML leaves, there were 14 common components, including tricyclene, α-pinene, camphene, sabinene, β-pinene, β-myrcene, α-phellandrene, d-limonene, eucalyptol, trans-β-ocimene, eucalyptol, ledol, eudesm-4 and β-linalool. In addition, α-pinene, camphene, β-pinene and linalool were common volatile components found in fresh leaves growing in all four seasons and in dry buds of MML. For essential oil, α-pinene, β-pinene, β-myrcene, β-linalool, linalool and myrcene had the highest contents in fresh leaves, indicating that MML leaves have health benefits and are suitable all year. Fresh leaves of MML in spring exhibited the highest rate of volatile oil extraction. This study on the differences and seasonal changes of volatile components in fresh MML leaves provides a scientific basis and guide for the seasonal selection of volatile oil extraction in MML and the construction of health care communities.
2017, 35(1): 115-121.
DOI: 10.11913/PSJ.2095-0837.2017.10115
Abstract：
Four-year-old Paris polyphylla Smith var. chinensis seedlings were cultured in five different concentrations (0, 5, 20, 80 and 160 mg/L) of lanthanum (La) solution. The effects of different application levels of La on the growth and rhizome saponin content were studied by comparing different vegetative growth indexes and components of rhizome saponins of P. polyphylla var. chinensis, as determined by HPLC. Results showed that La significantly impacted the growth and polyphyllin content of P. polyphylla var. chinensis. Polyphyllin content showed an increasing trend with the increase in La concentration; however, La concentrations of 160 mg/L inhibited P. polyphylla var. chinensis growth, which reduced plant height and increased specific leaf area. Overall, this study suggests that a La concentration of 80 mg/L is most conducive to the growth and accumulation of saponin in P. polyphylla var. chinensis.
Four-year-old Paris polyphylla Smith var. chinensis seedlings were cultured in five different concentrations (0, 5, 20, 80 and 160 mg/L) of lanthanum (La) solution. The effects of different application levels of La on the growth and rhizome saponin content were studied by comparing different vegetative growth indexes and components of rhizome saponins of P. polyphylla var. chinensis, as determined by HPLC. Results showed that La significantly impacted the growth and polyphyllin content of P. polyphylla var. chinensis. Polyphyllin content showed an increasing trend with the increase in La concentration; however, La concentrations of 160 mg/L inhibited P. polyphylla var. chinensis growth, which reduced plant height and increased specific leaf area. Overall, this study suggests that a La concentration of 80 mg/L is most conducive to the growth and accumulation of saponin in P. polyphylla var. chinensis.
2017, 35(1): 122-127.
DOI: 10.11913/PSJ.2095-0837.2017.10122
Abstract：
The bioactive compounds and antioxidant activity of the fruits and leaves of Rosa sterilis D. Shi in Guizhou province were analyzed using correlation analysis. The results indicated that gallic acid, rutin, quercetin, catechin, ellagic acid, chlorogenic acid, and ferulic acid were the major phenolic compounds in the fruits and leaves. The contents of bioactive compounds were significantly different between the fruit and leaves (P<0.05). The contents of p-coumaric acid, polyphenols and flavonoids were the highest in the fruit. However, the contents of gallic acid, catechin, chlorogenic acid, epicatechin, ferulic acid, ellagic acid, rutin, quercetin and polyphenols were higher in the leaves. The antioxidant activities of fruit were significantly higher than that of the leaves (P<0.05), flavonoids had a strong contribution to the total reducing power assay (TRPA) value, ascorbic acid had a strong contribution to the ferric ion reducing antioxidant power (FRAP) value, and quercetin had a strong contribution to the ABTS value. The fruits and leaves of R. sterilis D. Shi are of high value for the development of medicinal and edible resources.
The bioactive compounds and antioxidant activity of the fruits and leaves of Rosa sterilis D. Shi in Guizhou province were analyzed using correlation analysis. The results indicated that gallic acid, rutin, quercetin, catechin, ellagic acid, chlorogenic acid, and ferulic acid were the major phenolic compounds in the fruits and leaves. The contents of bioactive compounds were significantly different between the fruit and leaves (P<0.05). The contents of p-coumaric acid, polyphenols and flavonoids were the highest in the fruit. However, the contents of gallic acid, catechin, chlorogenic acid, epicatechin, ferulic acid, ellagic acid, rutin, quercetin and polyphenols were higher in the leaves. The antioxidant activities of fruit were significantly higher than that of the leaves (P<0.05), flavonoids had a strong contribution to the total reducing power assay (TRPA) value, ascorbic acid had a strong contribution to the ferric ion reducing antioxidant power (FRAP) value, and quercetin had a strong contribution to the ABTS value. The fruits and leaves of R. sterilis D. Shi are of high value for the development of medicinal and edible resources.
2017, 35(1): 128-137.
DOI: 10.11913/PSJ.2095-0837.2017.10128
Abstract：
Secondary metabolites derived from secondary metabolic pathways in plants play an important role in the adaptation of plants to the ecological environment, and represent a valuable source of natural medicines and industrial chemicals. bZIP transcription factors (TFs) belong to a large gene family and generally exist in eukaryotes. This review summarizes the structure and classification of bZIP TFs, with an emphasis on research progress, methods and the biosynthetic regulation of secondary metabolites, such as terpenoids, flavonoids and alkaloids. Future prospects are also discussed. Further research on the mechanisms of bZIP TFs will increase secondary metabolite production by genetic modification of biosynthetic pathways, with wider application prospects in medicine and industrial and agricultural production.
Secondary metabolites derived from secondary metabolic pathways in plants play an important role in the adaptation of plants to the ecological environment, and represent a valuable source of natural medicines and industrial chemicals. bZIP transcription factors (TFs) belong to a large gene family and generally exist in eukaryotes. This review summarizes the structure and classification of bZIP TFs, with an emphasis on research progress, methods and the biosynthetic regulation of secondary metabolites, such as terpenoids, flavonoids and alkaloids. Future prospects are also discussed. Further research on the mechanisms of bZIP TFs will increase secondary metabolite production by genetic modification of biosynthetic pathways, with wider application prospects in medicine and industrial and agricultural production.
