Combined Transcriptomic and Metabolomic Analysis Reveals the Role of Phenylpropanoid Biosynthesis Pathway in the Salt Tolerance Process of Sophora alopecuroides.

Salt stress is the main abiotic stress that limits crop yield and agricultural development. Therefore, it is imperative to study the effects of salt stress on plants and the mechanisms through which plants respond to salt stress. In this study, we used transcriptomics and metabolomics to explore the effects of salt stress on Sophora alopecuroides. We found that salt stress incurred significant gene expression and metabolite changes at 0, 4, 24, 48, and 72 h. The integrated transcriptomic and metabolomic analysis revealed that the differentially expressed genes (DEGs) and differential metabolites (DMs) obtained in the phenylpropanoid biosynthesis pathway were significantly correlated under salt stress. Of these, 28 DEGs and seven DMs were involved in lignin synthesis and 23 DEGs and seven DMs were involved in flavonoid synthesis. Under salt stress, the expression of genes and metabolites related to lignin and flavonoid synthesis changed significantly. Lignin and flavonoids may participate in the removal of reactive oxygen species (ROS) in the root tissue of S. alopecuroides and reduced the damage caused under salt stress. Our research provides new ideas and genetic resources to study the mechanism of plant responses to salt stress and further improve the salt tolerance of plants.

Effect of various mulches on soil physico-Chemical properties and tree growth (Sophora japonica) in urban tree pits.

Mulching is a widely employed soil management practice. The mulches used have variable effects on the soil properties and plant growth. In China, mulches are used to cover bare soil at a few places in landscapes, where most of the soil is uncovered, especially in tree pits. As to improve our understanding on the effect of various mulches on soil properties and tree growth after two years of the treatment justifying its implication in soil fertility and tree growth. A comparison study was conducted to determine the effects of inorganic (cobblestone-CB; water permeable brick-WPB), organic (pine bark-PB; green waste compost-GWC), and living (turf grass-TG) mulches on soil physical and chemical properties at three different depths (0-10 cm, 10-20 cm, and 20-40cm), and on tree growth (Sophora japonica) in urban tree pits. Soil moisture was measured once a month in 2015.The soil samples were collected from the tree pits two years after mulching and used to evaluate the physical and chemical properties. Further, trunk diameter and tree height were determined once a year. During the most months, all types of mulches significantly affected the moisture content of the soil at all the depths analyzed. In July and August, however, the moisture content of PB and TG treated soil decreased when compared with that of unmulched bare soil. Two years after mulching, the bulk density of the soil treated with PB, GWC, and TG was significantly affected at10-20 cm, with GWC exhibiting a relatively better effect. The treatments with PB, GWC, and TG also improved the total porosity, macroporosity, and microporosity of the soil at lower depths. Further, WPB worsened the bulk density and porosity of the soil, elevating the pH at lower depths. The organic matter, total N, mineral N, available P, and available K contents of the soil at lower depths increased when mulched with organic material. Turf grass significantly increased only the total N and available K at 0-10 and 10-20 cm. There was no significant difference in the soil properties among the treatments at 20-40 cm. Furthermore, the trunk diameter and tree height were not affected by the mulches two years after mulching. In conclusion, organic mulches especially GWC, not only increased soil fertility significantly but improved soil physical characters (0-10 cm depth) comparing to other mulches, are suitable to cover bare soil in urban tree pits.

[Effect of nitrogen, phosphorus and potassium fertilizers on Flos Sophorae Immaturus yield and quality in hilly area of Chongqing].

With Sophora japonica at the flowering stage as the object, the effect of nitrogen, phosphorus and potassium fertilizers on the yield composition factors, yield and quality of Flos Sophorae Immaturus (FSI) was studied. The results indicated that in early spring, nitrogen, phosphorus and potassium fertilizer on the amplification rate of S. japonica, FSI yield composition, yield and quality were different significantly, middle to high nitrogen (1.5-2.0 kg/plant) significantly increased the level of panicled clusters, raceme and flower bud number and yield. Phosphorus (1.5-2.0 kg/plant) could significantly increase the total buds of flower number and yield, potassium showed no significant increase in yield and yield components. Comprehensively considering yield and quality of FSI, nitrogen 1.5-2.0 kg/plant, phosphorus 1.5-2.0 kg/plant and potassium 0.6-0.9 kg/plant are appropriate.

Effects of road dust on the growth characteristics of Sophora japonica L. seedlings.

Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust's impacts on plants can be regarded as a combination of load, composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root-shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root-shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces.

Impact of Funneliformis mosseae on the growth, lead uptake, and localization of Sophora viciifolia.

On the basis of a pot experiment under lead (Pb) stress, we investigated the effects of an arbuscular mycorrhizal (AM) fungus (Funneliformis mosseae) on the growth and Pb uptake of Sophora viciifolia L., and explored the Pb localization in AM roots using transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). The results showed that high Pb levels (500 and 1000 µg/g) inhibited the growth of S. viciifolia seedlings. Compared with the noninoculation treatment, F. mosseae inoculation decreased the Pb concentrations above- and belowground by 61.0% and 15.2%, when exposed to Pb at a concentration of 1000 µg/g. The root length, fork number, tip number, surface area, and volume of mycorrhizal S. viciifolia were higher than those of the corresponding nonmycorrhizal plants. These parameters of mycorrhizal plants increased by 220%, 219%, 157%, 225%, and 278% when plants were exposed to Pb at 1000 µg/g compared with nonmycorrhizal plants. The ratio of root length with diameters between 0-0.2 mm to the total root length significantly increased under Pb stress, and F. mosseae inoculation significantly reduced the ratio. Under Pb stress, F. mosseae increased the ratios of root length with 0.61-0.8 and 0.81-1.0 mm diameters to the total root length, indicating that F. mosseae tended to thicken the roots of S. viciifolia under Pb additions. The combined results of TEM and EDS indicated that Pb deposited in not only plant cells but also the cell walls and vacuoles of the AM fungal intracellular hyphae, thus revealing the subcellular-level mechanism of AM fungi in alleviating the Pb toxicity to the host plant.

Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae) seeds.

The physical dormancy of seeds has been poorly studied in species from tropical forests, such as the Atlantic Forest. This study aimed to examine the effect of moderate alternating temperatures on breaking the physical dormancy of seeds, the morphoanatomy and histochemistry of seed coats, and to locate the structure/region responsible for water entrance into the seed, after breaking the physical dormancy of seeds of two woody Fabaceae (subfamily Faboideae) species that occur in the Brazilian Atlantic Forest: Sophora tomentosa and Erythrina speciosa. To assess temperature effect, seeds were incubated in several temperature values that occur in the Atlantic Forest. For morphological and histochemical studies, sections of fixed seeds were subjected to different reagents, and were observed using light or epifluorescence microscopy, to analyze the anatomy and histochemistry of the seed coat. Treated and nonreated seeds were also analyzed using a scanning electron microscope (SEM) to observe the morphology of the seed coat. To localize the specific site of water entrance, the seeds were blocked with glue in different regions and also immersed in ink. In the present work a maximum temperature fluctuation of 15 degrees C was applied during a period of 20 days and these conditions did not increase the germination of S. tomentosa or E. speciosa. These results may indicate that these seeds require larger fluctuation of temperature than the applied or/and longer period of exposition to the temperature fluctuation. Blocking experiments water inlet combined with SEM analysis of the structures of seed coat for both species showed that besides the lens, the hilum and micropyle are involved in water absorption in seeds scarified with hot water. In seeds of E. speciosa the immersion of scarified seeds into an aniline aqueous solution showed that the solution first entered the seed through the hilum. Both species showed seed morphological and anatomical features for seed coats of the subfamily Faboideae. Lignin and callose were found around all palisade layers and the water impermeability and ecological role of these substances are discussed in the work.

Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae) seeds / Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae) seeds

The physical dormancy of seeds has been poorly studied in species from tropical forests, such as the Atlantic Forest. This study aimed to examine the effect of moderate alternating temperatures on breaking the physical dormancy of seeds, the morphoanatomy and histochemistry of seed coats, and to locate the structure/region responsible for water entrance into the seed, after breaking the physical dormancy of seeds of two woody Fabaceae (subfamily Faboideae) species that occur in the Brazilian Atlantic Forest: Sophora tomentosa and Erythrina speciosa. To assess temperature effect, seeds were incubated in several temperature values that occur in the Atlantic Forest. For morphological and histochemical studies, sections of fixed seeds were subjected to different reagents, and were observed using light or epifluorescence microscopy, to analyze the anatomy and histochemistry of the seed coat. Treated and non-treated seeds were also analyzed using a scanning electron microscope (SEM) to observe the morphology of the seed coat. To localize the specific site of water entrance, the seeds were blocked with glue in different regions and also immersed in ink. In the present work a maximum temperature fluctuation of 15ºC was applied during a period of 20 days and these conditions did not increase the germination of S. tomentosa or E. speciosa. These results may indicate that these seeds require larger fluctuation of temperature than the applied or/and longer period of exposition to the temperature fluctuation. Blocking experiments water inlet combined with SEM analysis of the structures of seed coat for both species showed that besides the lens, the hilum and micropyle are involved in water absorption in seeds scarified with hot water. In seeds of E. speciosa the immersion of scarified seeds into an aniline aqueous solution showed that the solution first entered the seed through the hilum. Both species showed seed morphological and anatomical features for seed coats of the subfamily Faboideae. Lignin and callose were found around all palisade layers and the water impermeability and ecological role of these substances are discussed in the work.

Requisitos para romper la latencia en semillas de Sophora tomentosa y Erythrina speciosa (Fabaceae). La latencia física de las semillas ha sido poco estudiada en las especies de los bosques tropicales, como el bosque atlántico. Este estudio tuvo como objetivo examinar el efecto de las temperaturas moderadas alternantes en romper la latencia física de las semillas, la anatomía y la histoquímica de la cubierta de las semillas, y la localización de la estructura o región responsable de la entrada de agua, después de romper la latencia física de las semillas de Sophora tomentosa y Eythrina speciosa, dos especies leñosas de Fabaceae (subfamilia Faboideae) que presentes en el bosque atlántico de Brasil. Para cumplir con el primer objetivo se incubaron las semillas a varias temperaturas que se dan en el bosque atlántico. Para los estudios morfológicos e histoquímicos se fijaron secciones de semillas sometidos a diferentes reactivos y se observaron usando luz o microscopía de epifluorescencia para analizar la anatomía y la histoquímica de la cubierta de la semilla. Semillas tratadas y no tratadas se analizaron también usando un microscopio electrónico de barrido (MDB) o microscopio estereoscópico (ME) para observar la morfología de la cubierta de la semilla. Para localizar el sitio específico de la entrada de agua, las semillas fueron bloqueadas con pegamento en diferentes regiones y también sumergidas en tinta. En el presente trabajo se aplicó una fluctuación de temperatura máxima de 15°C durante un período de 20 días y estas condiciones no aumentó la germinación de S. tomentosa o E. speciosa. Estos resultados pueden indicar que estas semillas requieren mayor fluctuación de la temperatura que la aplicada y/o un período más largo de exposición a la fluctuación de la temperatura. Experimentos de bloqueo de entrada de agua combinada con el análisis de las estructuras de la cubierta de la semilla para ambas especies (SEM) mostró que, a pesar de la lente, el hilio y micropilo están implicados en la absorción de agua en las semillas escarificadas con agua caliente. En las semillas de E. speciosa la inmersión de semillas escarificadas en una solución acuosa de anilina mostró que la solución entró por primera vez a la semilla a través del hilio. Ambas especies mostraron características morfológicas y anatómicas de semillas con cubierta de la subfamilia Faboideae. La lignina y callosa se encontraron alrededor de todas las capas de empalizada y la impermeabilidad al agua y en el trabajo se discute el papel ecológico de estas sustancias.

Colonization and plant growth promoting characterization of endophytic Pseudomonas chlororaphis strain Zong1 isolated from Sophora alopecuroides root nodules.

The endophytic strain Zong1 isolated from root nodules of the legume Sophora alopecuroides was characterized by conducting physiological and biochemical tests employing gfp-marking, observing their plant growth promoting characteristics (PGPC) and detecting plant growth parameters of inoculation assays under greenhouse conditions. Results showed that strain Zong1 had an effective growth at 28 ºC after placed at 4-60 ºC for 15 min, had a wide range pH tolerance of 6.0-11.0 and salt tolerance up to 5% of NaCl. Zong1 was resistant to the following antibiotics (µg/mL): Phosphonomycin (100), Penicillin (100) and Ampicillin (100). It could grow in the medium supplemented with 1.2 mmol/L Cu, 0.1% (w/v) methylene blue and 0.1-0.2% (w/v) methyl red, respectively. Zong1 is closely related to Pseudomonas chlororaphis based on analysis the sequence of 16S rRNA gene. Its expression of the gfp gene indicated that strain Zong1 may colonize in root or root nodules and verified by microscopic observation. Furthermore, co-inoculation with Zong1 and SQ1 (Mesorhizobium sp.) showed significant effects compared to single inoculation for the following PGPC parameters: siderophore production, phosphate solubilization, organic acid production, IAA production and antifungal activity in vitro. These results suggest strains P. chlororaphi Zong1 and Mesorhizobium sp. SQ1 have better synergistic or addictive effect. It was noteworthy that each growth index of co-inoculated Zong1+SQ1 in growth assays under greenhouse conditions is higher than those of single inoculation, and showed a significant difference (p < 0.05) when compared to a negative control. Therefore, as an endophyte P. chlororaphis Zong1 may play important roles as a potential plant-growth promoting agent.

[Effect of transplantation on growth and oxymatrine content of Sophora flavescens].

OBJECTIVE: To study the effect of transplantation on the growth and oxymatrine content of Sophora flavescens and provide foundation for popularization and cultivation of Sophora flavescens in South China. METHODS: Sophora flavescens which was usually planted in North China and Northwest China was planted in a non-traditional location, Zhongshan city, Guangdong Province in South China to test its adaptability. The growth characters, such as plant height, leaf area, dry weight of root, diameter and length of root and so on were measured from 2010 to 2012. The oxymatrine content of one-year old and two-year old root of Sophora flavescens were determined by HPLC. Nine major growth indexes for one-year old Sophora flavescens were comprehensively analyzed and evaluated by the methods of weighted gray relational and hierarchy evaluation of fuzzy mathematics. RESULTS: The weighted relevancy of introduced and reference cultivars was 0.8545. The introduced cultivar was rather adaptable to the geography environment in Zhongshan. Its quality was very close to the reference cultivars. Oxymatrine content of root of one-year old and two-year old Sophora flavescens was 13.2784 mg/g (as much as origin) and 16.4779 mg/g (less than origin 28.67%), respectively. These were 10.65% and 37.32% higher than the quality standard which were set up in the Chinese Pharmacopoeia (2010 edition). CONCLUSION: Sophora flavescens performs quite well in the newly introducing region. It is suitable to be cultivated and extended in South China.

Colonization and plant growth promoting characterization of endophytic Pseudomonas chlororaphis strain Zong1 isolated from Sophora alopecuroides root nodules

The endophytic strain Zong1 isolated from root nodules of the legume Sophora alopecuroides was characterized by conducting physiological and biochemical tests employing gfp-marking, observing their plant growth promoting characteristics (PGPC) and detecting plant growth parameters of inoculation assays under greenhouse conditions. Results showed that strain Zong1 had an effective growth at 28 ºC after placed at 4-60 ºC for 15 min, had a wide range pH tolerance of 6.0-11.0 and salt tolerance up to 5% of NaCl. Zong1 was resistant to the following antibiotics (µg/mL): Phosphonomycin (100), Penicillin (100) and Ampicillin (100). It could grow in the medium supplemented with 1.2 mmol/L Cu, 0.1% (w/v) methylene blue and 0.1-0.2% (w/v) methyl red, respectively. Zong1 is closely related to Pseudomonas chlororaphis based on analysis the sequence of 16S rRNA gene. Its expression of the gfp gene indicated that strain Zong1 may colonize in root or root nodules and verified by microscopic observation. Furthermore, co-inoculation with Zong1 and SQ1 (Mesorhizobium sp.) showed significant effects compared to single inoculation for the following PGPC parameters: siderophore production, phosphate solubilization, organic acid production, IAA production and antifungal activity in vitro. These results suggest strains P. chlororaphi Zong1 and Mesorhizobium sp. SQ1 have better synergistic or addictive effect. It was noteworthy that each growth index of co-inoculated Zong1+SQ1 in growth assays under greenhouse conditions is higher than those of single inoculation, and showed a significant difference (p < 0.05) when compared to a negative control. Therefore, as an endophyte P. chlororaphis Zong1 may play important roles as a potential plantgrowth promoting agent.

[Developmental anatomy of anomalous structure and investigation of medicinal parts Sophora flavescens].

OBJECTIVE: To elucidate the composition structure of "annual rings" and the formation process of anomalous structures in Sophora flavescens, and further discuss the medicinal parts of S. flavescens. METHOD: Based on investigation on S. flavescens in its producing areas, the morphology of root systems was observed, and the developmental anatomy of roots was researched. RESULT: Creeping underground rhizomes of S. flavescen existed in some parts of the north place, there were many differences in appearance characters and microscopic features between these roots and rhizomes. Parenchyma cells in secondary xylem regained meristematic ability, became into anomalous cambia, and then developed into anomalous structures. "Annual rings" in transverse section of S. flavescens were not actually growth rings, they were made up of anomalous parenchyma girdle in secondary xylem and normal secondary structure. CONCLUSION: Roots are the medicinal parts of S. flavescens. This paper suggests that "annual rings" in the decoction pieces of S. flavescens should be called "annular structure".

[Analysis of the mineral elements of Sophora alopecuroides L. at different growth stages].

Mineral elements content,absoption proportion and requirement of Sophora alopecuroides L. at different stages were studied by ICP-AES technology. The results showed that (1) During mature period, the average proportion for N:K:Ca: Mg:P:Na was 11.91:8.27:7.54:1.02:1.00, and the average proportion for Fe:Zn:B:Cu:Mn was 28.91:2.12:1.40:1.18:1.00; (2) Mineral elements content of every part differs in each period, and stems at vegetative growth stage and seeds at mature period have the highest mineral elements content proportions of the whole plant which were about 45.6% and 36.7% respectively; (3) Sophora alopecuroides L. plants at vegetative growth stage have the largest fertilizer requirement, followed by the flowering period, and the smallest during pod period.

Using the pollen viability and morphology for fluoride pollution biomonitoring.

The methods using plants for biomonitoring of air and soil quality are simple, cheap, and fast and can supplement the classical physicochemical methods. In this study, biological pollen characterization of some collected legume species from an aluminum smelter area in Iran (IRALCO) was carried out to determine the actual value of pollen as a bioindicator of the effects of soil and atmospheric pollution. Young buds and flowers of six legumes (Cercis siliquastrum L., Medicago sativa L., Robinia pseudoacacia L., Melilotus officinalis (L.) lam, Trifolium repens L., and Sophora alopecuroides L.) in polluted and control plants were removed and compared. Studies of light and electron microscopic preparation showed some abnormalities during pollen development in affect of fluoride pollution. The viability of pollen grains estimated by staining with acetocarmine shows sharp differences in smearing advanced pollen grains from abnormal ones. Except M. officinalis, the pollen grains of C. siliquastrum, M. sativa, R. pseudoacacia, T. repens, and S. alopecuroides in polluted areas showed light, partial, or no staining with acetocarmine, whereas almost all of the control ones clearly stained. Observation of the pollen grains by light microscopy and scanning electron microscopy showed the significant effect of fluoride on shapes and sizes of pollen grains. The stimulation and inhibition of these pollen characteristics depend on the pollen species as well as on the pollutant and its concentration. Therefore, pollen grains provide essential information on biological impact of pollutants and they are good candidates for biomonitoring the atmospheric and edaphic pollutions.

[Effects of NaCl stress on the seedling growth and K(+)- and Na(+) -allocation of four leguminous tree species].

Taking the pot-cultured seedlings of four leguminous tree species (Albizia julibrissin, Robinia pseudoacacia, Sophora japonica, and Gleditsia sinensis) as test materials, this paper studied their growth indices, critical salt concentration (C50), and K+ and Na+ allocation under different levels of NaCl stress, aimed to understand the difference of test tree species in salt tolerance. NaCl stress inhibited the seedling growth of the tree species. Under NaCl stress, the dry matter accumulation decreased, while the root/shoot ratio increased, especially for A. julibrissin and G. sinensis. Quadratic regression analysis showed that the C50 of A. julibrissin, R. pseudoacacia, S. japonica, and G. sinensis was 3.0 per thousand, 5.0 per thousand, 4.5 per thousand, and 3.9 per thousand, respectively, i.e., the salt tolerance of the four tree species was in the order of R. pseudoacacia > S. japonica > G. sinensis > A. julibrissin. In the root, stem, and leaf of the four tree species seedlings, the Na+ content increased with the increase of NaCl stress, while the K+ content (except in the root of A. julibrissin) decreased after an initial increase, resulting in a larger difference in the K+/Na+ ratio in the organs. Under the same NaCl stress, the allocation of Na+ in different organs of the four tree species seedlings decreased in the order of root>stem>leaf, while that of K+ differed with tree species and NaCl stress, and leaf was the main storage organ for K+. The K+/Na+ ratio in different organs decreased in the sequence of leaf>stem>root. R. pseudoacacia under NaCl stress accumulated more K+ and less Na+ in stem and leaf, and had higher K+/Na+ ratio in all organs and higher dry mass, being assessed to be more salt-tolerant. In contrast, A. julibrissin under high NaCl stress accumulated more Na+ in stem and leaf, and had a lower K+/Na+ ratio in all organs and lower dry mass, being evaluated to be lesser salt-tolerant. The K+ accumulation in seedling stem and leaf and the Na+ retention in seedling root could be the main reasons for the salt tolerance of leguminous tree species under NaCl stress.

[Structural characteristics of Sophora moorcroftiana community on wind-sandy land in middle reaches of Yaluzangbu River].

Based on quadrat investigation and hierarchical cluster analysis, this paper studied the structural characteristics of Sophora moorcroftiana community at its different restoration succession stages on the wind-sandy land in middle reaches of Yaluzangbu River. The plant community on the wind-sandy land could be divided into 6 types, i.e., S. moorcroftiana community, Orinus thoroldii community, S. moorcroftiana < O. thoroldii community, S. moorcroftiana-O. thoroldii community, Artemisia weiibyii+S. moorcroftiana community, and S. moorcroftiana+A. weiibyii community. The restoration succession began with the sand-fixing S. moorcroftiana distributed on moving dune, followed by O. thoroldii invasion, and then, S. moorcroftiana-O. thoroldii community formed gradually. Another restoration succession approach began with O. thoroldii community, S. moorcroftiana occurred then, and finally, S. moorcroftiana-O, thoroldii community formed. On semi-fixed dune, A. weiibyi could invade the community, and S. moorcroftiana+A. weiibyi community formed. The climax community on the wind-sandy land was the shrub community dominated by S. moorcroftiana. With increasing slope grade, the coverage and height of S. moorcroftiana community tended to decrease. Biological crust had definite improvement effect on the soil physical and chemical properties. At the places with biological crust, surface soil water content was significantly higher, compared with that at the places with other restoration succession stages of S. moorcroftiana community. The crown diameter, plant height, and the sprouting branch number of S. moorcroftiana community were the highest on moving dune, followed by on fixed dune, and on semi-fixed dune. The dead branch number at different restoration succession stages indicated that S. moorcroftiana population had a declining trend after the sand was fixed.

Studies on the dynamic accumulations of Sophora alopecuroides L. Alkaloids in different harvest times and the appropriate harvest time.

A sensitive and accurate method for the simultaneous determination of five alkaloids, namely 9α-hydroxymatrine (M1), matrine (M2), sophoridine (M3), oxymatrine (M4), alopecurin A (M5) in different parts (seed, legume, stem, and root) and different harvest times of Sophora alopecuroides L. was developed by high performance liquid chromatography (HPLC) with photodiode array detector (PDA) for the first time. The separation by gradient elution was achieved on Scienhome Kromasil C(18) (4.6×250 mm, 5 µm) column at 30°C with acetonitrile (A)/0.1% phosphatic acid+0.1% triethylamine (B) as the mobile phase. The detection wavelength was 205 nm. The optimized method provided a good linear relation (r≥0.9993 for all the target compounds), satisfactory precision (RSD values less than 2.3%) and good recovery (96.4-103.6%). The limits of detection ranged between 0.11×10(-3) and 4.70×10(-3) µg for the different analytes. The method was successfully applied to analysis and quality control of alkaloid extracts from the traditional Chinese herbal drugs of S. alopecuroides L.

Diverse rhizobia associated with Sophora alopecuroides grown in different regions of Loess Plateau in China.

A total of seventy-five symbiotic bacterial strains isolated from root nodules of wild Sophora alopecuroides grown in different regions of China's Loess Plateau were characterized. Based on the combined RFLP patterns, thirty-five genotypes were defined among the rhizobia and they were classified into nine genomic species, including Mesorhizobium alhagi and M. gobiense as the main groups, as well as Agrobacterium tumefaciens, M. amorphae, Phyllobacterium trifolii, Rhizobium giardinii, R. indigoferae, Sinorhizobium fredii and S. meliloti as the minor groups according to the 16S rRNA and recA gene analyses. Five and three lineages of nodA and nifH were found, respectively, in these strains, implying that the symbiotic genes of the S. alopecuroides rhizobia had different origins or had divergently evolved. Results of correspondence analysis showed that there was a correlation between rhizobial genotypes and the geographic origins. Possible lateral transfer of the recA and 16S rRNA genes between the P. trifolii and A. tumefaciens strains, and that of symbiotic genes (nodA, nifH) between different genera, was shown by discrepancies of the phylogenetic relationships of the four gene loci. These results revealed diverse rhizobia associated with wild S. alopecuroides grown in different regions of China's Loess Plateau, and demonstrated for the first time the existence of symbiotic A. tumefaciens strains in root nodules of S. alopecuroides.

[Effects of environmental stress on seedlings root growth and nodulation of leguminous shrubs in the dry valley of Minjiang River].

A field investigation was made to understand the seedlings root nodulation, biomass accumulation, root length, and fine root percentage of Sophora davidii, Indigofera lenticellata and Campylotropis polyantha along an altitudinal gradient on two contrasting sloped hills (north Zongqu and south Jingzhoushan) in the dry valley of Minjiang River. In the meantime, a greenhouse experiment was conducted to study the adaptation responses of 2 month-old S. davidii and C. polyantha seedlings root nodulation to different soil moisture regimes (80%, 60%, 40%, and 20% WHC). For the three test shrub species, fewer nodules were observed at lower altitude (1600-1950 m) areas, the nodule number per plant of S. davidii, I. lenticellata, and C. polyantha being 0.1 +/- 0.1, 0.9 +/- 0.5, and 5.7 +/- 1.9, and the non-nodulation plant accounting for 65.1%, 12.3% and 17.6%, respectively. The nodule number of the three species increased with increasing altitude, and correlated positively with root length and fine root percentage. However, there were no significant differences in the plant growth and biomass at different altitudes. When the soil moisture content was lower than 60% WHC, the nodule number and the fresh and dry mass of both S. davidii and C. polyantha decreased markedly, and at 20% WHC, no nodule and only 9.8 +/- 3.6 nodules were observed for S. davidii and C. polyantha, respectively, indicating that in this dry valley, the root nodulation capability of endemic leguminous shrubs was very low. Comparing with S. davidii, C. polyantha had higher root nodulation capability and drought-resistance. Prior to introducing these shrub species in forestation practices, to keep the soil moisture content higher than 40% WHC was recommended for relatively efficient biological nitrogen fixation.

[Characterization of soil microbial community function and structure in rhizosphere of typical tree species and the meaning for environmental indication in the Loess Plateau].

Determination of the soil microbial community structure in rhizosphere of typical tree species in the Loess Plateau can be of great theoretical significance for correctly assessing the characteristics of soil ecological rehabilitation of the Loess Plateau. In this study,spore density analysis, microbial cultivation and BIOLOG were employed to evaluate the AMF spore density and soil microbial community diversity under four tree species with vesicular-arbuscular mycorrhizae in ecological rehabilitation area of the Loess Plateau, north Shaanxi Province. The results show that the different tree species differed significantly in both soil microbial number and microbial functional diversity, AMF spore density of Hippophae rhamnoides soil is 2.24 times than that of the Robinia pseudoacacia soil,and the rank as following order: Hippophae rhamnoides > Sophora viciifolia > Caragana microphylla > Robinia pseudoacacia . The statistical significant are detected in the bacteria and actinomyces numbers, however, there is no statistical significance in fungi number among the treatments. The principle component analyses indicates that scatter of Caragana microphylla and Hippophae rhamnoides are smaller than that of Sophora viciifolia and Robinia pseudoacacia, these results suggest that the soil community structure strongly varied among the different tree species. Numbers of carbon sources related to the first two components are 14 and 8. Correlation analysis shows that the AMF spore density appeared extremely significantly and positively correlated with the number of bacteria,and the metabolic of amino acids,amines and aromatic compounds, respectively. Moreover,AMF spore density positively correlated with the average well color development (AWCD), nevertheless, no correlations are found among AMF spore density, carboxylic acids,carbohydrates and polymers. These results suggest that AMF spore density is shown to be an important environmental biology parameter used in correctly assessing the soil bacteria metabolic community and diversity under the tree species in ecological rehabilitation of the Loess Plateau, north Shaanxi Province.

Quantitative expression analysis of the ABC genes in Sophora tetraptera, a woody legume with an unusual sequence of floral organ development.

Sophora is a woody genus of the Leguminosae in which an unusual order and process of floral organ development is often observed. The SEM results for Sophora tetraptera revealed precocious initiation of the carpel, delayed development of petals, and floral organ development interrupted by an unusual prolonged summer-autumn dormant period which occurred between organ initiation and organ differentiation. These observations provided an opportunity to track key floral identity genes over an extended developmental period. Homologues of LEAFY, APETALA1, PISTILLATA, and AGAMOUS were isolated from S. tetraptera. Real-time PCR enabled a simultaneous and quantitative analysis of both the temporal and spatial expression patterns of these four genes. Expression differences in the range of three to five orders of magnitude were detected between different genes and between different stages of flower development for the same gene. Although not functionally tested, the spatial expression patterns of the genes were consistent with expectations based on the ABC model of floral development. Their temporal expression patterns were consistent with the timing of flower initiation and the unusual order of organ development. Quantitatively, while the expression levels of the LFY homologue and the A-class gene were high during the periods of organ initiation and organ differentiation and low during the summer-autumn dormant period, high expression levels of the B- and C-class genes were detected only during the rapid, albeit delayed, phase of organ differentiation. Additionally, the sustained expression of the floral organ identity genes after differentiation reflects on-going roles for these genes during subsequent organ development.