云南陇川县香料烟覆膜与不覆膜栽培对比试验

为探究覆膜栽培和露地栽培对香料烟各项指标的影响,进行了田间试验。试验品种为当地常用优质品种云香巴斯玛1号,试验地点在陇川县章风镇迭撒村拉丙三组,设无膜露地栽培与覆膜栽培2个处理,不设重复。试验结果表明,覆膜栽培对香料烟的生育期、植物学性状、农艺性状、烟叶质量等方面均存在影响,表现优于无膜露地种植,建议在陇川县积极推广香料烟覆膜栽培技术,以有效提高种植户的经济收入,试验结果可为陇川县发展香料烟提供依据。

Leaf choice in black-and-white snub-nosed monkeys Rhinopithecus bieti is related to the physical and chemical properties of leaves

To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti, we collected mature leaves of nine food and five non-food plant species at the southernmost part of the species＇s range. Chemical properties such as fat, ash, crude protein （CP）, total phenolics （TP）, and fiber content including neutral detergent fiber （NDF）, acid detergent fiber （ADF）, lignin, celluloses and hemicelluloses, and physical toughness were measured. R. bieti tended to choose leaves with lower fiber content, higher ash, a higher ratio of CP/ADF, and lower toughness. No difference was found for fat, crude protein, total phenolics, hemicelluloses and lignin between food and non-food leaves. Even though the ratio of CP/ADF is generally regarded as a good indicator for colobine food choice, the difference in the ratio of CP/ADF between food and non-food leaves was only the result of differences in ADE Since positive correlations were found between ADF and tough- ness from all leaves （both food and non-food species）, and toughness of leaves was likely easier for R. bieti to sense than fiber content via mastication, the toughness of leaves may function as a predictor of food choice in this species [Current Zoology 56 （6） 643-49, 2010].

Essential Oil Composition of Six Pinus L. Taxa （Pinaceae） from Canada and Their Chemotaxonomy

In this study six Pinus L. taxa from Canada （P. strobus L., P. parviflora Siebold ＆ Zucc., P. mugo Turra subsp, mugo, P. resinosa Sol. ex Alton, P. flexilis E. James and P. nigra J. F. Arnold） were studied to determine on chemical characters of studied taxa. For this purpose, essential oil from needles of the six Pinus taxa were investigated by HS-SPME/GC-MS. 38, 33, 39, 28, 31 and 46 compounds were respectively identified from each species representing 95.90%, 95.07%, 95.79%, 96.20%, 93.05% and 96.25% of the oil. The results have given some clues on the chemotaxonomy of this genus and are of usable potentials of the plants as renewable resources. Although the essential oil composition of studied taxa showed chemical divergences because of climatical, seasonal, geographical and geological factors, but the major compounds of plant derivatives are generally similar and the major compounds are chemotaxonomical markers for studied taxa.

Soil microbial community composition and its driving factors in alpine grasslands along a mountain elevational gradient

Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soil microbial community of this type of vegetation in response to environmental change. Using phospholipid fatty acids （PLFA）, we investigated soil microbial community composition along an elevational gradient （3094-4131 m above sea level） on Mount Yajiageng, and we explored the impact of plant functional groups and soil chemistry on the soil microbial community. Except for Arbuscular Mycorrhizal fungi （AM fungi） biomarker 18：2ω6,9 increasing significantly, other biomarkers did not show a consistent trend with the elevational gradient. Microbial biomass quantified by total PLFAs did not show the elevational trend and had mean values ranging from 1.64 to 4.09 ktmol per g organic carbon （OC）, which had the maximum value at the highest site. Bacterial PLFAs exhibited a similar trend with total PLFAs, and its mean values ranged from 0.82 to 1.81 μmol （g OC）-1. The bacterial to fungal biomass ratios had the minimum value at the highest site, which might be related to temperature and soil total nitrogen （TN）. The ratios of Gram-negative to Gram-positive bacteria had a significantly negative correlation with soil TN and had the maximum value at the highest site. Leguminous plant coverage and soil TN explained 58% of the total variation in the soil microbial community and could achieve the same interpretation as the whole model. Other factors may influence the soil microbial community through interaction with leguminous plant coverage and soil TN. Soil chemistry and plant functional group composition in substantial amounts explained different parts of the variation within the soil microbial community, and the interaction between them had no impact on the soil microbial community maybe beeause long-term grazing greatly reduces litter. In sum, although there were obvious differences in soil microbial communities along the elevation gradient, there were no clear elevational trends found in general. Plant functional groups and soil chemistry respectively affect the different aspects of soil microbial community. Leguminous plant coverage and soil TN had important effects in shaping soil microbial community.

Determination of the Antioxidant, Phytochemical and Antibacterial Profiles of Flowers from Selected Ornamental Plants in Nueva Vizcaya, Philippines

With the increasing interest on natural products discovery, utilization of plant parts which are commonly disregarded is another breakthrough. This study sought to determine the secondary metabolites present, phenolic contents, radical scavenging activities and antibacterial properties of 10 selected ornamental flowers which were Adenium obesum, Allamanda cathartica, Bougainvillea glabra, Catharanthus roseus, Caesalpinia pulcherrima, Heliconia subulata, Ixora coccinea, Mussaenda philippica, Tecoma stans and Torenia fournieri, from Nueva Vizcaya, Philippines. The ethanolic crude extracts were subjected to thin layer chromatography （TLC） phytochemical screening. Total phenolics expressed as mg AAE/g sample were determined through Folin-Ciocalteu method. Radical scavenging activities were measured using DPPH assay. Antibacterial activities were assessed through TLC bioautography. To quantify bacterial susceptibility of C. pulcherrima, MIC and MBC were employed in the ethyl acetate sub-fraction. TLC showed different types of phenolics, alkaloids, essential oils and terpenes. T. fournieri showed the highest total phenolics with 155 mg AAE/g while H. subulatahad showed the lowest with 3.50 mg AAE/g. Measurement of IC59 showed that H. subulata had the highest antioxidant activity followed by T. fournieri with 303 ppm and 320 ppm, respectively. H. subulata having the least amount of total phenolics had greatest radical scavenging activity. This indicates that other than phenolics, other metabolites can pose great antioxidant activities. The antibacterial testing showed that M. philippica, 1. coccinea, 1-1. subulata, C. pulcherrima and A. cathartica were bioactive against Staphylococcus aureus and Escherichia coll. MIC and MBC of C. pulcherrima ethyl acetate sub-fraction is within the range of 2.5-10 mg/mL.

In vitro Antimicrobial Activity and Phytochemical Screening of Local Plants

Antimicrobial activity of extracts of local plants was evaluated, with two strain i.e E. coil and S. aurri （gram positive and gram negative） microorganisms. The in vitro anti bacterial activity was performed by agar disc diffusion method. The most active antibacterial plants were S. trifiliatus and A. mexicana. The significant antibacterial activity of active extracts was compared with the standered, antimicrobics, streptomycin （10 μg/disc）. The results obtained in the present study suggest that S. trifoliatus and A. mexicana can be used in treating diseases caused by the test organism.

Phytochemical Screening and Antimicrobial Evaluation of the Aqueous Extracts of Ammoides verticillata, an Endemic Species

Ammoides verticillata （Desf.） Briq. is an Algerian endemic species; the phytochemical screening （methods of Harborne, 1973） of the aerials parts wealth in polyphenol compounds： flavonoids, saponins, leucoanthocyanes, terpens and steroids and tannins; there is no alkaloids. There is an important quantity of essential oils in the flowers; the interest of this study is that this species remains until then it is not very known. The results of Aromatogram method by incorporation of Mtiller-Hinton on solid medium, showed a significant antimicrobial activity （method of Duraffourd, 1987） of the infusion and the ethanolic extract; the infusion of stems and flowers is indeed much more active on Echerichia coli, Citrobacter, Enterobacter, Staph aureus and Staph epidermidis, such as flowers extracts demonstrate an important antimicrobial activity on Staph aureus, Staph epidermidis, Streptococcus, Pseudomonas and Acinetobacter recognized as antibiotic resistant. This could give opportunities for using this species in the treatment of diverse infections and as a disinfecting additive on nosocomial area. The valorization, preservation and sustainable use ofAmmoides verticillata require the protection of its habitats.

Effects of elevated temperature on chemistry of an invasive plant,its native congener and their herbivores

Climatic warming affects plant growth and physiology,yet how warming alters chemistry in invasive plants and indirectly affects herbivorous insects remains largely unknown.Here,we explored warming-induced changes in leaf chemistry of the invasive plant Alternanthera philoxeroides and its native congener Alternanthera sessilis,and further examined how these changes affected the performance of the herbivores,Cassida piperata and Spodoptera litura.We conducted a simulated warming experiment to address its effects on 13 leaf chemical traits of A.philoxeroides and A.sessilis.We measured growth and development time of two herbivores reared on plants from warming or ambient controls.Warming significantly affected leaf chemistry composition for both the invasive and native Alternanthera.Warming decreased nitrogen concentration in A.philoxeroides and increased total flavonoid and total phenol concentration in A.sessilis.The effects of warming on nutrients(i.e.fructose,sucrose,total soluble sugar and starch)varied with individual chemicals and plant species.Weight of C.piperata pupal and S.litura larval reared on warming-treated A.sessilis significantly decreased compared with non-warmed control,and a similar pattern was observed for weight of S.litura larval feeding on warming-treated A.philoxeroides.In addition,warming-treated A.sessilis significantly prolonged larval development time of S.litura.These results indicate that warming can directly affect the leaf chemistry in both invasive plant and its native congener,but these effects vary by species.Such differences in warming-induced changes in plant chemistry could indirectly affect herbivorous insects associated with the invasive and native plants.

Phytochemistry,biological properties and quality control of Chuanxiong Rhizoma:a review

Chuanxiong Rhizoma is a widely used Chinese herbal medicine in the past 2000 years.Chuanxiong Rhizoma is composed of volatile oils,phthalide lactones,phenolic acids,polysaccharides and other compounds.To date,more than 149 compounds in Chuanxiong Rhizoma have been isolated and identified,and some of them have been reported to possess promising biological properties on cardiovascular and central nervous system disorders besides their anti-cancer and antioxidant effects.Modulation of inflammatory mediators and apoptotic factors are believed to contribute to its bioactivities.Analytical methods,such as HPLC,GC and UPLC,are employed for qualitative evaluation of Chuanxiong Rhizoma.In this work,harvest period,growing habitat,processing method and storage,which can affect the quality of Chuanxiong Rhizoma,were also discussed.Comprehensive quality control methods should be developed to ensure the safety,quality and efficacy use of Chuanxiong Rhizoma.Herein,we collected and analyzed the literature of Chuanxiong Rhizoma published on CNKI,ScienceDirect,Springer link,Wiley and PubMed in past two decades,and up-to-date information of Chuanxiong Rhizoma was provided in this paper.We suggested ligustilide,butylidenephthalide and total senkyunolides as the chemical markers to evaluate the quality of Chuanxiong Rhizoma.Additionally,the influences of soil conditions and processing methods on Chuanxiong Rhizoma as future research perspectives should also be further assessed.

Elevated CO_2 Accelerates Phosphorus Depletion by Common Bean(Phaseolus vulgaris) in Association with Altered Leaf Biochemical Properties

Phosphorus （P） is a major limiting factor for plant productivity in many ecosystems and agriculture. The projected increase in atmospheric CO2 is likely to result in changes in plant mineral consumption and growth. We studied P depletion by common bean （Phaseolus vulgaris） cultured hydroponically under ambient （377±77μmol mol^-1） or elevated （650±32 μmol mol^-1） CO2 in media of low or high P. Under elevated CO2 compared to ambient CO2, the maximum P depletion rate increased by 98% at low P and 250% at high P, and P was depleted about 2-5 weeks sooner; leaf acid phosphatase （APase） activity and chlorophyll content both increased significantly; root-to-shoot ratio increased significantly at high P, although it was unaffected at low P; lateral root respiration rate showed no change, suggesting that COs did not affect P depletion via metabolic changes to the roots; the total biomass at final harvest was significantly higher at both low and high P. Our data showed that the increased rate and amount of P depletion during plant growth under elevated CO2 occurred in association with alterations in leaf biochemical properties, i.e., enhanced activities of leaf APase and increased leaf chlorophyll content.

Modeling the effects of cross-protection control in plant disease with seasonality

Cross-protection in plants has been widely used to control losses caused by virus diseases in the world. Here, a non-autonomous plant-virus disease model was developed includ- ing cross-protection. Global dynamics of the model was discussed. Under the quite weak assumptions, integral form conditions were resolved for permanence of the system and extinction of diseases. Furthermore, we looked into the sufficient conditions that plants could be protected against the detrimental effects of infection by an infection with the mild virus isolates. Last, we performed numerical simulations. Our investigations sug- gested that cross-protection played an important role in controlling the spread of the challenging virus in plants.