Plants as highly diverse sources of construction wood, handicrafts and fibre in the Heihe valley (Qinling Mountains, Shaanxi, China): the importance of minor forest products.

BACKGROUND: Chinese rural communities living among species-rich forests have little documentation on species used to make handicrafts and construction materials originating from the surrounding vegetation. Our research aimed at recording minor wood uses in the Heihe valley in the Qinling mountains. METHODS: We carried out 37 semi-structured interviews in seven villages. RESULTS: We documented the use of 84 species of plants. All local large canopy trees are used for some purpose. Smaller trees and shrubs which are particularly hard are selectively cut. The bark of a few species was used to make shoes, hats, steamers and ropes, but this tradition is nearly gone. A few species, mainly bamboo, are used for basket making, and year-old willow branches are used for brushing off the chaff during wheat winnowing. CONCLUSIONS: The traditional use of wood materials documented suggests that some rare and endangered tree species may have been selectively cut due to their valuable wood, e.g. Fraxinus mandshurica and Taxus wallichiana var. chinensis. Some other rare species, e.g. Dipteronia sinensis, are little used and little valued.

A morel improved growth and suppressed Fusarium infection in sweet corn.

A post-fire morel collected from Populus simonii stands in Mt. Qingling was identified as Morchella crassipes Mes-20 by using nuclear ribosomal DNA internal transcribed spacer phylogeny. It was inoculated into sweet corn to observe colonized roots in purified culture and in greenhouse experiments. The elongation and maturation zones of sweet corn were remarkably colonized at the cortex intercellular and intracellular cells, vessel cells, and around the Casparian strip, forming ectendomycorrhiza-like structures. Colonization was also observed in the zone of cell division proximal to the root cap. Greenhouse assays with sweet corn showed that this morel stimulated the development of the root system and significantly increased the dry root biomass. M. crassipes also significantly reduced the incidence of Fusarium verticillioides in the kernels of mature ears when inoculated into young ears before Fusarium inoculation and prevented Fusarium infection in corn ears compared with that of the control in the greenhouse. When grown under axenic conditions, M. crassipes produced the phytohormones abscisic acid, indole-3-acetic acid, and salicylic acid. The benefits to plants elicited by M. crassipes may result from these phytohormones which may improve the drought resistance, biomass growth and resistance to Fusarium.

Wild food plants and fungi used in the mycophilous Tibetan community of Zhagana (Tewo County, Gansu, China).

BACKGROUND: The aim of the study was to investigate knowledge and use of wild food plants and fungi in a highland valley in the Gannan Tibetan Autonomous Region on the north-eastern edges of the Tibetan Plateau. METHODS: Field research was carried out in four neighbouring villages in a mountain valley of the Diebu (Tewo) county, surrounded by spruce forests. The study consisted of 30 interviews with single informants, or group interviews (altogether 63 informants). Apart from collecting voucher specimens, we also identified fungi using DNA barcoding. RESULTS: We recorded the use of 54 species of vascular plants. We also recorded the use of 22 mushroom taxa, which made up the largest category of wild foods. Fruits formed the largest category of food plants, with 21 species, larger than the wild greens category, which consisted of 20 species eaten after boiling or frying and 7 as raw snacks. We also recorded the alimentary use of 10 species of edible flowers and 3 species with underground edible organs. On average, 20.8 edible taxa were listed per interview (median - 21). The most listed category of wild foods was green vegetables (mean - 7.5 species, median - 8 species), but fruits and mushrooms were listed nearly as frequently (mean - 6.3, median - 6 and mean - 5.8, - median 6 respectively). Other category lists were very short, e.g., flowers (mean - 1.3, median - 1) and underground edible parts (mean - 0.7, median - 1). Wild vegetables are usually boiled and/or fried and served as side-dishes, or their green parts are eaten as snacks during mountain treks (e.g., peeled rhubarb shoots). Wild fruits are mainly collected by children and eaten raw, they are not stored for further use. The most widely used wild staple foods are Potetilla anserina roots, an important ceremonial food served on such occasions as New Year or at funerals. They are boiled and served with sugar and butter. The most important famine plants remembered by people are the aerial bulbils of Persicaria vivipara. Flowers are used as children's snacks - their nectar is sucked. CONCLUSIONS: The number of wild taxa eaten in the studied valley is similar to that of other Tibetan areas. The structure of wild food plant taxa is also very typical for Tibetan speaking areas (e.g., the use of rhubarb shoots, Potentilla anserina, Persicaria vivipara). The studied community show a high level of mycophilia.

The anti-tumor activity and mechanism of alkaloids from Aconitum szechenyianum Gay.

In the current study, the anti-tumor activity of Aconitum szechenyianum Gay alkaloids (ASA) and its mechanism of action were investigated. The result showed that ASA could induce apoptosis in HepG-2, Hela and A549 cells but not in normal human embryonic kidney 293A cells, and its apoptotic effect on A549 cells was stronger than those of HepG-2 and Hela cells. Moreover, the following study showed that ASA could up-regulate the expression levels of p38 and phosphorylated p38 MAPK, suggesting ASA-induced apoptosis was associated with the p38 MAPK mediated pathway. Furthermore, ASA could up-regulate TNF-R1 and DR5 via activation of p38 MAPK, thereby activating caspase 8, revealing the death receptor pathway was also involved in this process. In addition, ASA could led to a loss in the mitochondrial out membrane potential, up-regulate p53, phosphorylated p53 and Bax, down-regulate Bcl-2, release cytochrome c from the mitochondria to the cytoplasm, and activate caspase-9 and caspase-3 in A549 cells, which revealed that ASA could also induce apoptosis through the mitochondria mediated pathway. These results suggested that ASA played the anti-tumor role through the activation of p38 MAPK-, death receptor-, mitochondria- and caspase-dependent apoptotic pathways.

Aza-polycyclic aromatic hydrocarbons from Saruma henryi.

A new azafluoranthene alkaloid, named sarumine (1), along with six known N-containing derivatives of phenanthrenes, 2-7, were isolated from the whole herb of Saruma henryi. Their structures were elucidated on the basis of extensive spectroscopic analysis. Moreover, antimicrobial activities of all compounds were evaluated.

Molecular characterization and expression analyses of an anthocyanin synthase gene from Magnolia sprengeri Pamp.

Anthocyanin synthase (ANS), which catalyzes the conversion of colorless leucoanthocyanins into colored anthocyanins, is a key enzyme in the anthocyanin biosynthetic pathway. It plays important roles in plant development and defense. An ANS gene designated as MsANS was cloned from Magnolia sprengeri using rapid amplification of complementary DNA (cDNA) ends technology. The full-length MsANS is 1171-bp long and contains a 1080-bp open reading frame encoding a 360 amino acid polypeptide. In a sequence alignment analysis, the deduced MsANS protein showed high identity to ANS proteins from other plants: Prunus salicina var. cordata (74 % identity), Ampelopsis grossedentata (74 % identity), Pyrus communis (73 % identity), and Prunus avium (73 % identity). A structural analysis showed that MsANS belongs to 2-oxoglutarate (2OG)- and ferrous iron-dependent oxygenase family because it contains three binding sites for 2OG. Real-time quantitative polymerase chain reaction analyses showed that the transcript level of MsANS was 26-fold higher in red petals than in white petals. The accumulation of anthocyanins in petals of white, pink, and red M. sprengeri flowers was analyzed by HPLC. The main anthocyanin was cyanidin-3-o-glucoside chloride, and the red petals contained the highest concentration of this pigment.

Genome-wide transcriptome analysis of genes involved in flavonoid biosynthesis between red and white strains of Magnolia sprengeri pamp.

BACKGROUND: Magnolia sprengeri Pamp is one of the most highly valuable medicinal and ornamental plants of the Magnolia Family. The natural color of M. sprengeri is variable. The complete genome sequence of M. sprengeri is not available; therefore we sequenced the transcriptome of white and red petals of M. sprengeri using Illumina technology. We focused on the identity of structural and regulatory genes encoding the enzymes involved in the determination of flower color. RESULTS: We sequenced and annotated a reference transcriptome for M. sprengeri, and aimed to capture the transcriptional determinanats of flower color. We sequenced a normalized cDNA library of white and red petals using Illumina technology. The resulting reads were assembled into 77,048 unique sequences, of which 28,243 could be annotated by Gene Ontology (GO) analysis, while 48,805 transcripts lacked GO annotation. The main enzymes involved in the flavonoid biosynthesis, such as phenylalanine ammonia-Lyase, cinnamat-4-Hydroxylase, dihydroflavonol-4-reductase, flavanone 3-hydroxylase, flavonoid-3'-hydroxylase, flavonol synthase, chalcone synthase and anthocyanidin synthase, were identified in the transcriptome. A total of 270 transcription factors were sorted into three families, including MYB, bHLH and WD40 types. Among these transcription factors, eight showed 4-fold or greater changes in transcript abundance in red petals compared with white petals. High-performance liquid chromatography analysis of anthocyanin compositions showed that the main anthocyanin in the petals of M. sprengeri is cyanidin-3-O-glucoside chloride and its content in red petals was 26-fold higher than that in white petals. CONCLUSION: This study presents the first next-generation sequencing effort and transcriptome analysis of a non-model plant from the Family Magnoliaceae. Genes encoding key enzymes were identified and the metabolic pathways involved in biosynthesis and catabolism of M. sprengeri flavonoids were reconstructed. Identification of these genes and pathways adds to the current knowledge of the molecular biology and biochemistry of their production in plant. Such insights into the mechanisms supporting metabolic processes could be used to genetically to enhance flower color among members of the Magnoliaceae.

[Soil respiration characteristics in the clear-cutting site of Quercus aliena var. acuteserrata forest in Xiaolong Mountain in Qinling Mountains].

By using Li-6400 portable photosynthesis system with soil chamber, the soil respiration rates (Rs) of Quercus aliena var. acuteserrata forest land (control site) and their clear-cutting site were measured in Xiaolong Mountain of Qinling Mountains from May 2011 to April 2012 to understand the diurnal and monthly dynamics of soil respiration rate and the influences from soil temperature, soil moisture, soil physical and chemical properties. The results showed that both diurnal and monthly dynamics of soil respiration rate presented a single-peak curve, similar to the variation of soil temperature at the clear-cutting and control sites. During the study period, the maximum monthly mean values of soil respiration rate at the clear-cutting and control sites occurred in July (4.63 and 4.01 micromol x m(-2) x s(-1), respectively) and the minimum values presented in February (0.10 and 0.30 micromol x m(-2) x s(-1), respectively). Soil respiration rate in 4-6 months after clear-cutting was higher than at the control site, and became lower afterwards. 89. 6% -90. 8% of soil respiration rate variation was interpreted by the multiple regression models of soil temperature, soil moisture and their interaction at the clear-cutting site, and 94.7%-95.5% at the control site. The Q10 values computed by exponential equations were 3.47-4.22 and 3.54-3.96 at the clear-cutting and control sites, respectively. The C fluxes at the clear-cutting and control sites were 344.8 and 512.9 g x m(-2) annually, and 24.2 and 40.9 g x m(-2) in winter, respectively.

Wild food plants used by the Tibetans of Gongba Valley (Zhouqu county, Gansu, China).

BACKGROUND: The ethnobotany of Tibetans is a seriously under-studied topic. The aim of the study was to investigate knowledge and use of wild food plants in a valley inhabited by Tibetans in the Gannan Tibetan Autonomous Region. METHODS: The field research was carried out in a wooded mountain valley in 9 neighbouring villages the Zhouqu (Brugchu) county, and comprised 17 interviews with single informants and 14 group interviews, involving 122 people altogether. RESULTS: We recorded the use of 81 species of vascular plants from 41 families. Fruits formed the largest category, with 42 species, larger than the wild greens category, with 36 species. We also recorded the culinary use of 5 species of edible flowers, 7 species with underground edible organs and 5 taxa of fungi. On average, 16.2 edible taxa were listed per interview (median - 16). Green vegetables formed the largest category of wild foods (mean - 8.7 species, median - 9 species), but fruits were listed nearly as frequently (mean - 6.9, median - 6). Other categories were rarely mentioned: flowers (mean - 0.2, median - 0), underground edible parts (mean - 0.3, median - 0) and mushrooms (mean - 1.5, - median 1).Wild vegetables are usually boiled and/or fried and served as side-dishes (cai). They are often lacto-fermented. Wild fruits are mainly collected by children and eaten raw, they are not stored for further use. The most widely used wild vegetables are: Eleuterococcus spp., Pteridium aquilinum, Helwingia japonica, Aralia chinensis, Allium victorialis, Pteridium aquilinum, Ixeris chinensis, Thlaspi arvense and Chenopodium album. The culinary use of Caltha palustris as a green vegetable is very interesting. In its raw state, marsh marigold is a toxic plant, due to the presence of protoanemonin. In this area it is dried or lactofermented before use. The most commonly eaten fruits are: Pyrus xerophila, Prunus salicina, Berchemia sinica, Rubus spp. and Eleagnus umbellata. CONCLUSIONS: The number of wild taxa eaten in the studied valley is relatively large compared to most studies from around the world. However, compared to the northern slope of the Qinling, in Shaanxi, the list is considerably shorter, in spite of the similar methodology applied and similar research effort involved.

Wild food plants and wild edible fungi in two valleys of the Qinling Mountains (Shaanxi, central China).

BACKGROUND: The aim of the study was to investigate knowledge and use of wild food plants in two mountain valleys separated by Mount Taibai--the highest peak of northern China and one of its biodiversity hotspots, each adjacent to species-rich temperate forest vegetation. METHODS: Seventy two free lists were collected among the inhabitants of two mountain valleys (36 in each). All the studied households are within walking distance of primary forest vegetation, however the valleys differed in access to urban centers: Houzhenzi is very isolated, and the Dali valley has easier access to the cities of central Shaanxi. RESULTS: Altogether, 185 wild food plant species and 17 fungi folk taxa were mentioned. The mean number of freelisted wild foods was very high in Houzhenzi (mean 25) and slightly lower in Dali (mean 18). An average respondent listed many species of wild vegetables, a few wild fruits and very few fungi. Age and male gender had a positive but very low effect on the number of taxa listed.Twelve taxa of wild vegetables (Allium spp., Amaranthus spp., Caryopteris divaricata, Helwingia japonica, Matteucia struthiopteris, Pteridium aquilinum, Toona sinensis, Cardamine macrophylla, Celastrus orbiculatus, Chenopodium album, Pimpinella sp., Staphylea bumalda &S. holocarpa), two species of edible fruits (Akebia trifoliata, Schisandra sphenanthera) and none of the mushrooms were freelisted by at least half of the respondents in one or two of the valleys. CONCLUSION: The high number of wild vegetables listed is due to the high cultural position of this type of food in China compared to other parts of the world, as well as the high biodiversity of the village surroundings. A very high proportion of woodland species (42%, double the number of the ruderal species used) among the listed taxa is contrary to the general stereotype that wild vegetables in Asia are mainly ruderal species. The very low interest in wild mushroom collecting is noteworthy and is difficult to explain. It may arise from the easy access to the cultivated Auricularia and Lentinula mushrooms and very steep terrain, making foraging for fungi difficult.

[Carbon sequestration of young Robinia pseudoacacia plantation in Loess Plateau].

In order to understand the carbon sequestration of ecological forests in Loess Plateau, a comparative study was made on the organic carbon density (OCD) of soil, litter, and plant organs in an 8-year-old Robinia pseudoacacia plantation and nearby barren land. Comparing with the barren land, the young R. pseudoacacia plantation had a decrease (0.26 kg x m(-2)) of soil OCD, but the OCD in its litter, root system, and aboveground organs increased by 121.1%, 202.0%, and 656. 7%, respectively, with a total carbon sequestration increased by 3.3% annually, which illustrated that R. pseudoacacia afforestation on Loess Plateau had an obvious positive effect on carbon sequestration.

[Spatial distribution pattern of Larix chinensis population in Taibai Mt].

Larix chinensis is an endangered species only distributed in Qinling Mountains of China. It has a concentrated distribution in Taibai Mt., and plays an important role in environmental protection in the high altitude. After an investigation on fifteen 400 m2 plots, a comparative study on the spatial distribution pattern of L. chinensis population and its dynamics was made by the tests of discrete distribution pattern and aggregation intensity. The results showed that at different sampling areas, L. chinensis populations all performed the pattern of clustering distribution. As the sampling area increased, the congregating intensity of L. chinensis population appeared the pattern of high-->low-->high, but the highest congregation occurred in the areas of 100 m2 and 25 m2. The clustering intensity went down from low to high altitude, and the area with the highest clustering intensity occurred on that of 25 m2 in low altitude, 150 m2 in middle altitude, and 100 m2 in higher altitude. The clustering intensity in shade slope was higher than that in sunny slope, and the area with the highest clustering intensity was 100 m2 on shade slope, and 150 m2 on sunny slope. With the population age increased, the distribution pattern had a trend from clustering to random, the clustering intensity decreased somewhat, and the area with the highest clustering intensity was 150 m2 in young or old stages, and 100 m2 in middle stage. The distribution pattern of L. chinensis population was related to its ecological characteristics, community composition, and environmental factors. In situ conservation should be strengthened in the future. In lower altitude or on shade slope, the measurements of thinning no-aim in tree and shrub species should be taken; while in higher altitude area or sunny slope, thinning shrub species in patch form would be better for L. chinensis populations block renovating. The fostering area for L. chinensis populations should be suit to the area with the highest clustering intensity of populations.