Characterization, antibacterial, total antioxidant, scavenging, reducing power and ion chelating activities of green synthesized silver, copper and titanium dioxide nanoparticles using Artemisia haussknechtii leaf extract.

Science.gov (United States)

Alavi, Mehran; Karimi, Naser

2017-12-12

Recently, major problem related to pathogenic bacteria is augmentation of antibiotic resistance which has been changed treatment and recovery of millions of infectious patients. The present study reports an eco-friendly, rapid and easy method for synthesis of silver (Ag), copper (Cu) and titanium dioxide (TiO 2 ) nanoparticles (NPs) using Artemisia haussknechtii leaf aqueous extract with antibacterial activities against multi-drug resistance (MDR) bacteria species. Three different concentrations (0.001, 0.01 and 0.1 M) of AgNO 3 , CuSO 4 and TiO (OH) 2 were investigated for obtaining optimum NPs green synthesis. Total phenolic content, total flavonoid content of leaf extract and total antioxidant activity (DPPH) assay were determined as radical scavenging methods. UV-Visible spectroscopy, Fourier transform infrared spectroscopy analysis, X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscope and atomic force microscopy (AFM) were used due to NPs characterization. The size average of the Ag, Cu and TiO 2 NPs obtained were respectively 10.69 ± 5.55, 35.36 ± 44.4 and 92.58 ± 56.98 nm. In the case of antibacterial assay, disc diffusion assay, minimum inhibitory concentration, minimum bactericidal concentration, bacterial growth and morphology of four MDR species Staphylococcus aureus ATCC 43300, Staphylococcus epidermidis ATCC 12258, Serratia marcescens ATTC13880 and Escherichia coli ATCC 25922 were evaluated. Results of this study demonstrated that A. haussknechtii leaf extract with various groups of phytochemicals such as phenols and flavonoids had suitable ability in green synthesis of Ag, Cu and TiO 2 NPs. Also, Ag and Cu NPs had more antibacterial activities compared to TiO 2 NPs.

BIOLOGICALLY ACTIVE COMPOUNDS OF ARTEMISIA ANNUA. ESSENTIAL OIL

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D. A. Konovalov

2016-01-01

Full Text Available Artemisia annua is a herblike annual plant which has been used in Chinese folk medicine for more than 2,000 years. In 1970-s sesquiterpenic lactone of artemisinin was isolated from the above-ground part of this plant. Today it is the most efficient known natural and synthetic compound for malaria treatment. The purpose of the study was to review the data from the open sources about a component composition of Artemisia annua essential oil in the spectrum of its pharmacological activity. Methods. The study was carried out using information and searching sources (PubMed, ScholarGoogle, library data bases (eLibrary, Cyberleninca, as well as the results of our studies. Results. We have established that aboveground part of Artemisia annua have a significant amount  of essential oil apart from the sesquiterpene lactones. Essential oil contains more than 120 components, which belong to different classes of natural compounds. The study for dynamics of the essential oil accumulation in the Artemisia annua herb showed that the amount of oil in the herb rises significantly during budding, reaching maximum value in blossom. Qualitative composition and quantitative content of certain components varies depending on ecological and  geographical factors,  plant growing phase, cultivation technology, drying methods etc. Well-known pharmacological studies of essential oil of the Artemisia annua characterize it as a prospective source for the development of new antimicrobial medicinal drugs. Besides, as the studies shown, it can be related to the 6 class according to K. Sidorov’s classification – “relatively non-hazardous substances”. Conclusion. The analysis of the open sources on the study of essential oil of Artemisia annua made by us, as well as the results of our own studies, including phytochemical studies allow characterizing the essential oil of Artemisia annua as a prospective source for the working out of new antimicrobial drugs.

BIOLOGICALLY ACTIVE COMPOUNDS OF ARTEMISIA ANNUA. SESQUITERPENE LACTONES

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D. A. Konovalov

2016-01-01

Full Text Available Artemisia annua is an herblike annual plant which has been used in Chinese folk medicine for more than 2,000 years. In 1970-s sesquiterpene lactones of artemisinin was isolated from the aboveground part of this plant. Today it is the most efficient known natural and synthetic compound for malaria treatment.The purpose of the study was the review of the information from the open sources about the study for sesquiterpene lactones of Artemisia annua referring to its pharmacological activity.Methods. The study was carried out using informational and search engines (PubMed, ScholarGoogle, library databases (eLibrary, Cyberleninca, and the results of our own researches.Results. It was established that apart from the essential oil and phenolic compounds, aboveground part of Artemisia annua, it contains a significant amount of sesquiterpene lactones. Qualitative content and quantitative composition of sesquiterpene lactones varies depending on the ecological and geographic factors, plants growing phase, cultivation technology, drying methods etc. Well-known pharmacological studies of the extracts from Artemisia annua herb with sesquiterpene lactones, as well as individual compounds of this group characterize this type of raw materials as a perspective source for more profound research.Conclusion. Our analysis of the open materials on the sesquiterpene lactones of Artemisia annua, including phytochemical and pharmacological ones, allows characterization of the Artemisia annua herb as a perspective source for new drugs working out.

Phytochemical Contents of Five Artemisia Species

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Murat KURSAT

2015-12-01

Full Text Available In the present study, the fatty acid compositions, vitamin, sterol contents and flavonoid constituents of five Turkish Artemisia species (A. armeniaca, A. incana , A. tournefortiana, A. haussknechtii and A. scoparia were determined by GC and HPLC techniques. The results of the fatty acid analysis showed that Artemisia species possess high saturated fatty acid compositions. On the other hand, the studied Artemisia species were found to have low vitamin and sterol contents. Eight flavononids (catechin, naringin, rutin, myricetin, morin, naringenin, quercetin, kaempferol were determined in the present study. It was found that Artemisia species contained high levels of flavonoids. Morin (45.35 ± 0.65 – 1406.79 ± 4.12 μg/g and naringenin (15.32 ± 0.46 – 191.18 ± 1.22 μg/g were identified in all five species. Naringin (268.13 ± 1.52 – 226.43 ± 1.17 μg/g and kaempferol (21.74 ± 0.65 – 262.19 ± 1.38 μg/g contents were noted in the present study. Present research showed that the studied Artemisia taxa have high saturated fatty acids and also rich flavonoid content.

Preparation of Au and Ag nanoparticles using Artemisia annua and their in vitro antibacterial and tyrosinase inhibitory activities

Energy Technology Data Exchange (ETDEWEB)

Basavegowda, Nagaraj; Idhayadhulla, Akber; Lee, Yong Rok, E-mail: yrlee@yu.ac.kr

2014-10-01

This work describes a plant-mediated approach to the preparation of metal nanoparticles using leaf extract of Artemisia annua (A. annua), an ethno-medicinal plant widely found in Asia, which was used as reducing and stabilizing agent. A. annua is used in traditional Chinese medicine to alleviate fever. Au and Ag nanoparticles were prepared using a one-step aqueous method at room temperature without any toxic chemicals. The formation of Au and Ag nanoparticles was monitored by UV–vis spectroscopy. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA). TEM analysis of Au nanoparticles showed that they had triangular and spherical shapes with sizes ranging from 15 to 40 nm. The silver nanoparticles were predominantly spherical and uniformly sized (30–50 nm). The Au and Ag nanoparticles produced showed significant tyrosinase inhibitory and antibacterial effects. These results suggest that the synthesized nanoparticles provide good alternatives in varied medical and industrial applications. - Highlights: • Au and Ag nanoparticles were synthesized using Artemisia annua leaf aqueous extract. • Nanoparticles were characterized by UV–vis spectroscopy, FT-IR, TEM, EDX, XRD, and TGA. • Au and Ag nanoparticles were of size 25 and 30 nm respectively, in spherical forms. • Nanoparticles showed significant tyrosinase inhibitory and antibacterial activities.

Preparation of Au and Ag nanoparticles using Artemisia annua and their in vitro antibacterial and tyrosinase inhibitory activities

International Nuclear Information System (INIS)

Basavegowda, Nagaraj; Idhayadhulla, Akber; Lee, Yong Rok

2014-01-01

This work describes a plant-mediated approach to the preparation of metal nanoparticles using leaf extract of Artemisia annua (A. annua), an ethno-medicinal plant widely found in Asia, which was used as reducing and stabilizing agent. A. annua is used in traditional Chinese medicine to alleviate fever. Au and Ag nanoparticles were prepared using a one-step aqueous method at room temperature without any toxic chemicals. The formation of Au and Ag nanoparticles was monitored by UV–vis spectroscopy. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA). TEM analysis of Au nanoparticles showed that they had triangular and spherical shapes with sizes ranging from 15 to 40 nm. The silver nanoparticles were predominantly spherical and uniformly sized (30–50 nm). The Au and Ag nanoparticles produced showed significant tyrosinase inhibitory and antibacterial effects. These results suggest that the synthesized nanoparticles provide good alternatives in varied medical and industrial applications. - Highlights: • Au and Ag nanoparticles were synthesized using Artemisia annua leaf aqueous extract. • Nanoparticles were characterized by UV–vis spectroscopy, FT-IR, TEM, EDX, XRD, and TGA. • Au and Ag nanoparticles were of size 25 and 30 nm respectively, in spherical forms. • Nanoparticles showed significant tyrosinase inhibitory and antibacterial activities

Artemisia pollen-indicated steppe distribution in southern China during the Last Glacial Maximum

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Liu Hongyan

2013-07-01

Full Text Available The Last Glacial Maximum (LGM was the coldest period during the previous 20,000 years. There have been different points of views on steppe distribution during the LGM period in southern China, partly due to the different interpretations of Artemisia occurrences. To make a reliable interpretation of the pollen fossil Artemisia, the modern distribution of Artemisia species and the relationship of pollen with climate and vegetation over a large spatial scale in China was thoroughly analyzed. Information about Artemisia species and pollen distributions used in this paper were collected from published works completed by other researchers as well as ourselves. The southern limit of steppe vegetation during the LGM period was interpreted from the published contour map of Artemisia pollen percentages during the LGM. Artemisia species in China are mostly distributed either in the horizontally distributed steppe regions or in the vertically distributed desert-steppe in the desert region, which indicates a cold and dry climate. The steppe is a distribution center of Artemisia pollen. Fractions of Artemisia in surface pollen assemblages are lower in both the desert and the temperate forest. Neither high Artemisia species cover nor high percentages of Artemisia pollen were found in the coast areas of China. Twenty-five percent of Artemisia pollen in sediments might indicate a local occurrence of steppe vegetation. Percentages of Artemisia pollen in the subtropical and tropical forest are less than 10%. A close relationship between Artemisia pollen and temperate steppe in China is demonstrated. The southern edge of the steppe vegetation during the LGM might be along the middle reach of the Yangtze River. Our results support the hypothesis that the isolated high fraction of Artemisia pollen along the northern edge of the South China Sea was transported from a large source area.

Laboratory evaluation of Artemisia annua L. extract and artemisinin activity against Epilachna paenulata and Spodoptera eridania.

Science.gov (United States)

Maggi, María E; Mangeaud, Arnaldo; Carpinella, María C; Ferrayoli, Carlos G; Valladares, Graciela R; Palacios, Sara M

2005-07-01

Ethanolic extract of aerial parts of Artemisia annua L. and artemisinin were evaluated as anti-insect products. In a feeding deterrence assay on Epilachna paenulata Germ (Coleoptera: Coccinellidae) larvae, complete feeding rejection was observed at an extract concentration of 1.5 mg/cm2 on pumpkin leaf tissue. The same concentration produced a feeding inhibition of 87% in Spodoptera eridania (Cramer) (Lepidoptera: Noctuidae). In a no-choice assay, both species ate less and gained less weight when fed on leaves treated with the extract. Complete mortality in E. paenulata and 50% mortality in S. eridania were observed with extract at 1.5 mg/cm2. Artemisinin exhibited a moderate antifeedant effect on E. paenulata and S. eridania at 0.03-0.375 mg/cm2. However, a strong effect on survival and body weight was observed when E. paenulata larvae were forced to feed on leaves treated at 0.03 and 0.075 mg/cm2. Artemisia annua ethanolic extract of aerial parts at 1.5 mg/cm2 showed no phytotoxic effect on pumpkin seedlings.

Artemisia scoparia – A new source of artemisinin

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Aditi Singh

2010-03-01

Full Text Available Artemisinin is considered as the most active and potent antimalarial drug. Till date Artemisia annua Linn. plant is the only source for its production The present investigation was carried out with an objective to search a new plant for artemisinin. An attempt was made on a perennial faintly odoratus herb, Artemisia scoparia Waldst et Kit. to find out an alternative of A. annua for the production of artemisinin. The yield of artemisinin was higher in aerial plant parts (0.015% in comparison to callus culture (0.001%. The present study concluded that Artemisia scoparia contains an antimalarial drug artemisinin.

Artemisia scoparia – A new source of artemisinin

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Aditi Singh

2010-06-01

Full Text Available Artemisinin is considered as the most active and potent antimalarial drug. Till date Artemisia annua Linn. plant is the only source for its production The present investigation was carried out with an objective to search a new plant for artemisinin. An attempt was made on a perennial faintly odoratus herb, Artemisia scoparia Waldst et Kit. to find out an alternative of A. annua for the production of artemisinin. The yield of artemisinin was higher in aerial plant parts (0.015% in comparison to callus culture (0.001%. The present study concluded that Artemisia scoparia contains an antimalarial drug artemisinin.

Polyploid response of Artemisia annua L. to colchicine treatment

Science.gov (United States)

Yunus, A.; Parjanto; Samanhudi; Hikam, M. P.; Widyastuti, Y.

2018-03-01

Artemisia (Artemisia annua) is a a medicinal herb originated from Asia, its contains Artemisinin for malaria (caused by Plasmodium falciparum) treatment. Artemisinin content in A. annua are relatively low, ranging from 0.01% -0.5%. In order to increase the Artemisinin content, polyploid induction could be one effort to be done. For that, this experiment aims to examine the effect of colchicine on morphological characteristics and the induction of polyploidization in Artemisia plants. Polyploid induction on Artemisia annua L. seeds was performed by soaking the Artemisia seeds in colchicine (0%, 0,05%, 0,1% and 0,2%; concentration based) for 2 hours. The experimental design was Completely Randomized Design, one factor, 4 colchicine treatments and in each treatment 7 replicate. The results showed that polyploid occur in plants treated with 0.05% colchicine concentration and its morphological characteristic are 89.4 cm height, 30 branches, 15.9 CCI chlorophyll content, 0.78 cm stem diameter, and chromosome number 2n = 27. In the stomata density of polyploid plants (treated by 0.05% colchicine) was 130 number/mm2 with stomata diameter of 22.8 μm.

Hypocholesterolemic and antiatherosclerotic effect of artemisia aucheri in hypercholesterolemic rabbits.

Science.gov (United States)

Dinani, N Jafari; Asgary, Asgary; Madani, H; Naderi, Gh; Mahzoni, P

2010-07-01

Atherosclerosis which results from gradual deposition of lipids in arteries is a leading cause of mortality worldwide. Diet is one of the most important factors underlying atherosclerosis. High-cholesterol diets enhance atherosclerosis and vegetarian diets are known to slow down the process. Artemisia aucheri is an herb of the Composite family. Many species of Artemisia have proven hypolipidemic and antioxidant properties. This study determine the effects of Artemisia aucheri on lipoproteins and atherosclerosis in hypercholesterolemic rabbits. Fifteen male rabbits were randomly divided into three groups. Normal diet group, high-cholesterol diet group (1% cholesterol) and Artemisia aucheri group (1% cholesterol diet supplemented with 100 mg/kg body weight the Artemisi aucheri every other day). Biochemical factors were measured at the start, end of the first and second months of the study. At the end of the study, the aorta were removed for assessment of atherosclerotic plaques. The results indicate that Artemisia aucheri significantly reduced the level of total cholesterol, LDL cholesterol and triglycerids and increased HDL cholesterol. The degree of atherosclerotic thickness was significantly reduced in the treated group. Therefore, Artemisia aucheri is one of the useful herbal medicine for preventation of atherosclerosis and more studies in this regard is recommended.

[Flavonoids of Artemisia campestris, ssp. glutinosa].

Science.gov (United States)

Hurabielle, M; Eberle, J; Paris, M

1982-10-01

Four flavanones (pinostrobin, pinocembrin, sakuranetin and naringenin), one dihydroflavonol (7-methyl aromadendrin) and one flavone (hispidulin) have been isolated from Artemisia campestris L. ssp. glutinosa Gay and identified by spectroscopic methods. Artemisia campestris L. sous-espèce glutinosa Gay est une Composée Anthémidée largement répandue sur les sables du littoral méditerranéean et abondante dans certaines régions d'Espagne et d'Italie. Dans le cadre d'une étude chimiotaxonomique du genre Artemisia Tourn., nous nous sommes intéressés à l'analyse des flavonoïdes, composés jamais décrits, à notre connaissance, dans cette espèce d' Artemisia. Les sommités fleuries d' Artemisia campestris sous-espèce glutinosa, séchées et pulvérisées, sont dégraissées à l'ether de pétrole et épuisées par le chloroforme. Le fractionnement de l'extrait chloroformique, par chromatographie sur colonne de silice, et la purification de certaines fractions conduisent à l'isolement de six génines flavoniques, à l'etat pur. L' étude des spectres UV, des spectres de masse et des spectres de RMN [1,2] et la comparaison avec des échantillons authentiques permettent de proposer, pour ces flavonoïdes, les structures de la pinostrobine [3], de la pinocembrine [4], de la sakuranétine, de la naringénine [5] (flavanones), de la méthyl-7-aromadendrine, [6, 7] (dihydroflavonol) et de l'hispiduline [8, 9] (flavone); quatre de ces génines sont méthylées. Parmi ces flavonoïdes, la pinostrobine n'a jamais été décrite, à notre connaissance, dans la famille des Composées; la pinocembrine, la sakuranétine et la naringénine ont déjà été signalées chez quelques Astéracées et Eupatoriées [10], et l'hispiduline dans la tribu des Anthémidées ( Santolina chamaecyparissus L.) [8]. Seule, la méthyl-7-aromadendrine semble décrite, à ce jour, dans le genre Artemisia Tourn. [7].

Selection and Clonal Propagation of High Artemisinin Genotypes of Artemisia annua

Science.gov (United States)

Wetzstein, Hazel Y.; Porter, Justin A.; Janick, Jules; Ferreira, Jorge F. S.; Mutui, Theophilus M.

2018-01-01

Artemisinin, produced in the glandular trichomes of Artemisia annua L. is a vital antimalarial drug effective against Plasmodium falciparum resistant to quinine-derived medicines. Although work has progressed on the semi-synthetic production of artemisinin, field production of A. annua remains the principal commercial source of the compound. Crop production of artemisia must be increased to meet the growing worldwide demand for artemisinin combination therapies (ACTs) to treat malaria. Grower artemisinin yields rely on plants generated from seeds from open-pollinated parents. Although selection has considerably increased plant artemisinin concentration in the past 15 years, seed-generated plants have highly variable artemisinin content that lowers artemisinin yield per hectare. Breeding efforts to produce improved F1 hybrids have been hampered by the inability to produce inbred lines due to self-incompatibility. An approach combining conventional hybridization and selection with clonal propagation of superior genotypes is proposed as a means to enhance crop yield and artemisinin production. Typical seed-propagated artemisia plants produce less than 1% (dry weight) artemisinin with yields below 25 kg/ha. Genotypes were identified producing high artemisinin levels of over 2% and possessing improved agronomic characteristics such as high leaf area and shoot biomass production. Field studies of clonally-propagated high-artemisinin plants verified enhanced plant uniformity and an estimated gross primary productivity of up to 70 kg/ha artemisinin, with a crop density of one plant m-2. Tissue culture and cutting protocols for the mass clonal propagation of A. annua were developed for shoot regeneration, rooting, acclimatization, and field cultivation. Proof of concept studies showed that both tissue culture-regenerated plants and rooted cutting performed better than plants derived from seed in terms of uniformity, yield, and consistently high artemisinin content. Use of

Artemisia systematics and phylogeny: Cytogenetic and molecular insights

Science.gov (United States)

Joan Valles; E. Durant. McArthur

2001-01-01

The genus Artemisia (Asteraceae, Anthemideae, Artemisiinae) is a large genus, one of the largest genera in its family. It is comprised of about 500 taxa at the specific or subspecific level, distributed in 5 sections or subgenera. Most species are perennial and many are landscape dominants of arid or semiarid regions. Artemisia is widely distributed in the Northern...

Variation in the chemical composition of essential oils from Artemisia ...

African Journals Online (AJOL)

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Methods: The essential oils were obtained from fresh and dried leaves of Artemisia afra using ... Keywords: Artemia salina, Artemisia afra, Essential oils, hydrodistillation, ..... by Kayode and Afolayan [11] that the dried seed .... foodborne fungi.

Applying high-resolution melting (HRM) technology to identify five commonly used Artemisia species.

Science.gov (United States)

Song, Ming; Li, Jingjian; Xiong, Chao; Liu, Hexia; Liang, Junsong

2016-10-04

Many members of the genus Artemisia are important for medicinal purposes with multiple pharmacological properties. Often, these herbal plants sold on the markets are in processed forms so it is difficult to authenticate. Routine testing and identification of these herbal materials should be performed to ensure that the raw materials used in pharmaceutical products are suitable for their intended use. In this study, five commonly used Artemisia species included Artemisia argyi, Artemisia annua, Artemisia lavandulaefolia, Artemisia indica, and Artemisia atrovirens were analyzed using high resolution melting (HRM) analysis based on the internal transcribed spacer 2 (ITS2) sequences. The melting profiles of the ITS2 amplicons of the five closely related herbal species are clearly separated so that they can be differentiated by HRM method. The method was further applied to authenticate commercial products in powdered. HRM curves of all the commercial samples tested are similar to the botanical species as labeled. These congeneric medicinal products were also clearly separated using the neighbor-joining (NJ) tree. Therefore, HRM method could provide an efficient and reliable authentication system to distinguish these commonly used Artemisia herbal products on the markets and offer a technical reference for medicines quality control in the drug supply chain.

Fire tolerance of a resprouting Artemisia (Asteraceae) shrub

Science.gov (United States)

Winter, S.L.; Fuhlendorf, S.D.; Goad, C.L.; Davis, C.A.; Hickman, K.R.; Leslie, David M.

2011-01-01

In North America, most Artemisia (Asteraceae) shrub species lack the ability to resprout after disturbances that remove aboveground biomass. We studied the response of one of the few resprouting Artemisia shrubs, Artemisia filifolia (sand sagebrush), to the effects of prescribed fires. We collected data on A. filifolia density and structural characteristics (height, canopy area, and canopy volume) in an A. filifolia shrubland in the southern Great Plains of North America. Our study sites included areas that had not been treated with prescribed fire, areas that had been treated with only one prescribed fire within the previous 5 years, and areas that had been treated with two prescribed fires within the previous 10 years. Our data were collected at time periods ranging from 1/2 to 5 years after the prescribed fires. Density of A. filifolia was not affected by one or two fires. Structural characteristics, although initially altered by prescribed fire, recovered to levels characteristic of unburned areas in 3-4 years after those fires. In contrast to most non-sprouting North American Artemisia shrub species, our research suggested that the resprouting A. filifolia is highly tolerant to the effects of fire. ?? 2011 Springer Science+Business Media B.V.

Expression of Beta-glucosidase increases trichome density and artemisinin content in transgenic Artemisia annua plants

Science.gov (United States)

Singh, Nameirakpam Dolendro; Kumar, Shashi; Daniell, Henry

2015-01-01

Artemisinin is highly effective against multidrug-resistant strains of Plasmodium falciparum, the etiological agent of the most severe form of malaria. However, a low level of accumulation of artemisinin in Artemisia annua is a major limitation for its production and delivery to malaria endemic areas of the world. While several strategies to enhance artemisinin have been extensively explored, enhancing storage capacity in trichome has not yet been considered. Therefore, trichome density was increased with the expression of β glucosidase (bgl1) gene in A. annua through Agrobacterium-mediated transformation. Transgene (bgl1) integration and transcript was confirmed by molecular analysis. Trichome density increased up to 20% in leaves and 66% in flowers of BGL1 transgenic plants than Artemisia control plants. High-performance liquid chromatography (HPLC, MS-TOF) data showed that artemisinin content increased up to 1.4% in leaf and 2.56% in flowers (g-1DW), similar to the highest yields achieved so far through metabolic engineering. Artemisinin was enhanced up to 5-fold in BGL1 transgenic flowers. The present study opens the possibility of increasing artemisinin content by manipulating trichomes density, which is a major reservoir of artemisinin. Combining biosynthetic pathway engineering with enhancing trichome density may further increase artemisinin yield in A. annua. Because oral feeding of Artemisia plant cells reduced parasitemia more efficiently than the purified drug, reduced drug resistance and cost of prohibitively expensive purification process, enhanced expression should play a key role in making this valuable drug affordable to treat malaria in a large global population that disproportionally impacts low-socioeconomic areas and underprivileged children. PMID:26360801

Cytogeography and chromosome evolution of subgenus Tridentatae of Artemisia (Asteraceae)

Science.gov (United States)

E. Durant McArthur; Stewart C. Sanderson

1999-01-01

The subgenus Tridentatae of Artemisia (Asteraceae: Anthemideae) is composed of 11 species of various taxonomic and geographic complexities. It is centered on Artemisia tridentata with its three widespread common subspecies and two more geographically confined ones. Meiotic chromosome counts on pollen mother cells...

talking back: biography as friendship in anna banti's artemisia1

African Journals Online (AJOL)

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Writing the life of another woman requires some of the same qualities ... marks Artemisia's second death; the first being the artist's prolonged absence from ..... has come under discussion again in a recent debate following the publication of monographs .... post-war Italy, the narrator recognises Artemisia's struggle and.

Expression of β-glucosidase increases trichome density and artemisinin content in transgenic Artemisia annua plants.

Science.gov (United States)

Singh, Nameirakpam Dolendro; Kumar, Shashi; Daniell, Henry

2016-03-01

Artemisinin is highly effective against multidrug-resistant strains of Plasmodium falciparum, the aetiological agent of the most severe form of malaria. However, a low level of accumulation of artemisinin in Artemisia annua is a major limitation for its production and delivery to malaria endemic areas of the world. While several strategies to enhance artemisinin have been extensively explored, enhancing storage capacity in trichome has not yet been considered. Therefore, trichome density was increased with the expression of β-glucosidase (bgl1) gene in A. annua through Agrobacterium-mediated transformation. Transgene (bgl1) integration and transcript were confirmed by molecular analysis. Trichome density increased up to 20% in leaves and 66% in flowers of BGL1 transgenic plants than Artemisia control plants. High-performance liquid chromatography, time of flight mass spectrometer data showed that artemisinin content increased up to 1.4% in leaf and 2.56% in flowers (per g DW), similar to the highest yields achieved so far through metabolic engineering. Artemisinin was enhanced up to five-fold in BGL1 transgenic flowers. This study opens the possibility of increasing artemisinin content by manipulating trichomes' density, which is a major reservoir of artemisinin. Combining biosynthetic pathway engineering with enhancing trichome density may further increase artemisinin yield in A. annua. Because oral feeding of Artemisia plant cells reduced parasitemia more efficiently than the purified drug, reduced drug resistance and cost of prohibitively expensive purification process, enhanced expression should play a key role in making this valuable drug affordable to treat malaria in a large global population that disproportionally impacts low-socioeconomic areas and underprivileged children. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Comparison of Artemisia annua bioactivities between traditional medicine and chemical extracts

KAUST Repository

Nageeb, Ahmed

2014-04-04

The present work investigates the efficacy of using Artemisia annua in traditional medicine in comparison with chemical extracts of its bioactive molecules. In addition, the effects of location (Egypt and Jericho) on the bioactivities of the plant were investigated. The results showed that water extracts of Artemisia annua from Jericho have stronger antibacterial activities than organic solvent extracts. In contrast, water and organic solvent extracts of the Artemisia annua from Egypt do not have anti-bacterial activity. Furthermore, while the methanol extract of EA displayed high anticancer affects, the water extract of Egypt and the extracts of Jericho did not show significant anticancer activity. Finally, the results showed that the methanol and water extracts of Jericho had the highest antioxidant activity, while the extracts of Egypt had none. The current results validate the scientific bases for the use of Artemisia annua in traditional medicine. In addition, our results suggest that the collection location of the Artemisia annua has an effect on its chemical composition and bioactivities. - See more at: http://www.eurekaselect.com/121416/article#sthash.2c2j9AoL.dpuf

Comparison of Artemisia annua bioactivities between traditional medicine and chemical extracts

KAUST Repository

Nageeb, Ahmed; Altawashi, Azza; Emwas, Abdul-Hamid M.; Al-Talla, Zeyad; Al Rifai, Nahla

2014-01-01

The present work investigates the efficacy of using Artemisia annua in traditional medicine in comparison with chemical extracts of its bioactive molecules. In addition, the effects of location (Egypt and Jericho) on the bioactivities of the plant were investigated. The results showed that water extracts of Artemisia annua from Jericho have stronger antibacterial activities than organic solvent extracts. In contrast, water and organic solvent extracts of the Artemisia annua from Egypt do not have anti-bacterial activity. Furthermore, while the methanol extract of EA displayed high anticancer affects, the water extract of Egypt and the extracts of Jericho did not show significant anticancer activity. Finally, the results showed that the methanol and water extracts of Jericho had the highest antioxidant activity, while the extracts of Egypt had none. The current results validate the scientific bases for the use of Artemisia annua in traditional medicine. In addition, our results suggest that the collection location of the Artemisia annua has an effect on its chemical composition and bioactivities. - See more at: http://www.eurekaselect.com/121416/article#sthash.2c2j9AoL.dpuf

Molecular phylogeny of Subtribe Artemisiinae (Asteraceae), including Artemisia and its allied and segregate genera

Science.gov (United States)

Watson, Linda E; Bates, Paul L; Evans, Timothy M; Unwin, Matthew M; Estes, James R

2002-01-01

Background Subtribe Artemisiinae of Tribe Anthemideae (Asteraceae) is composed of 18 largely Asian genera that include the sagebrushes and mugworts. The subtribe includes the large cosmopolitan, wind-pollinated genus Artemisia, as well as several smaller genera and Seriphidium, that altogether comprise the Artemisia-group. Circumscription and taxonomic boundaries of Artemisia and the placements of these small segregate genera is currently unresolved. Results We constructed a molecular phylogeny for the subtribe using the internal transcribed spacers (ITS) of nuclear ribosomal DNA analyzed with parsimony, likelihood, and Bayesian criteria. The resulting tree is comprised of three major clades that correspond to the radiate genera (e.g., Arctanthemum and Dendranthema), and two clades of Artemisia species. All three clades have allied and segregate genera embedded within each. Conclusions The data support a broad concept of Artemisia s.l. that includes Neopallasia, Crossostephium, Filifolium, Seriphidium, and Sphaeromeria. However, the phylogeny excludes Elachanthemum, Kaschgaria, and Stilnolepis from the Artemisia-group. Additionally, the monophyly of the four subgenera of Artemisia is also not supported, with the exception of subg. Dracunculus. Homogamous, discoid capitula appear to have arisen in parallel four to seven times, with the loss of ray florets. Thus capitular morphology is not a reliable taxonomic character, which traditionally has been one of the defining characters. PMID:12350234

De novo assembly and analysis of the Artemisia argyi transcriptome and identification of genes involved in terpenoid biosynthesis.

Science.gov (United States)

Liu, Miaomiao; Zhu, Jinhang; Wu, Shengbing; Wang, Chenkai; Guo, Xingyi; Wu, Jiawen; Zhou, Meiqi

2018-04-11

Artemisia argyi Lev. et Vant. (A. argyi) is widely utilized for moxibustion in Chinese medicine, and the mechanism underlying terpenoid biosynthesis in its leaves is suggested to play an important role in its medicinal use. However, the A. argyi transcriptome has not been sequenced. Herein, we performed RNA sequencing for A. argyi leaf, root and stem tissues to identify as many as possible of the transcribed genes. In total, 99,807 unigenes were assembled by analysing the expression profiles generated from the three tissue types, and 67,446 of those unigenes were annotated in public databases. We further performed differential gene expression analysis to compare leaf tissue with the other two tissue types and identified numerous genes that were specifically expressed or up-regulated in leaf tissue. Specifically, we identified multiple genes encoding significant enzymes or transcription factors related to terpenoid synthesis. This study serves as a valuable resource for transcriptome information, as many transcribed genes related to terpenoid biosynthesis were identified in the A. argyi transcriptome, providing a functional genomic basis for additional studies on molecular mechanisms underlying the medicinal use of A. argyi.

A test for clinal variation in Artemisia californica and associated arthropod responses to nitrogen addition.

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Meza-Lopez, Maria M; Mooney, Kailen A; Thompson, Amanda L; Ho, Nicole K; Pratt, Jessica D

2018-01-01

The response of plant traits to global change is of fundamental importance to understanding anthropogenic impacts on natural systems. Nevertheless, little is known about plant genetic variation in such responses or the indirect effect of environmental change on higher trophic levels. In a three-year common garden experiment, we grew the shrub Artemisia californica from five populations sourced along a 700 km latitudinal gradient under ambient and nitrogen (N) addition (20 kg N ha-1) and measured plant traits and associated arthropods. N addition increased plant biomass to a similar extent among all populations. In contrast, N addition effects on most other plant traits varied among plant populations; N addition reduced specific leaf area and leaf percent N and increased carbon to nitrogen ratios in the two northern populations, but had the opposite or no effect on the three southern populations. N addition increased arthropod abundance to a similar extent among all populations in parallel with an increase in plant biomass, suggesting that N addition did not alter plant resistance to herbivores. N addition had no effect on arthropod diversity, richness, or evenness. In summary, genetic variation among A. californica populations mediated leaf-trait responses to N addition, but positive direct effects of N addition on plant biomass and indirect effects on arthropod abundance were consistent among all populations.

Dicty_cDB: Contig-U15609-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available H641784 ) CHO_OF4972xp21r1.ab1 CHO_OF4 Nicotiana tabacum ge... 54 0.002 2 ( DY336731 ) OB_SEa04L12.r OB_SEa Ocimum basil...nt WO2007093776. 38 0.029 3 ( DQ508732 ) Perkinsus marinus delta9-elongating activity prot... 38 0.029 3 ( D...Y036171 ) CAIY2568.fwd CAIY Artemisia annua leaf Artemisia ... 42 0.33 2 ( AW6512...9 2 ( EY042621 ) CAIY6316.fwd CAIY Artemisia annua leaf Artemisia ... 42 0.39 2 ( EH069644 ) PMDAD81TO Perki...nsus marinus small insert cDNA lib... 38 0.41 2 ( EY042620 ) CAIY6316.rev CAIY Artemisia annua leaf Artemi

Evaluation of DNA barcode candidates for the discrimination of Artemisia L.

Science.gov (United States)

Liu, Geyu; Ning, Huixia; Ayidaerhan, Nurbolati; Aisa, Haji Akber

2017-11-01

Because of the very similar morphologies and wide diversity of Artemisia L. varieties, they are difficult to identify, and there have been many arguments about the systematic classification Artemisia L., especially concerning the division of species. DNA barcode technology is used to rapidly identify species based on standard short DNA sequences. To evaluate seven candidate DNA barcodes (ITS, ITS2, psbA-trnH, rbcL, matK, rpoB, and rpoC1) regarding their ability to identify closely related species of the Artemisia genus in Xinjiang. The corresponding PCR amplification efficiency, detectable genetic divergence, identification efficiency and phylogenetic tree were assessed. We found that the internal transcribed spacer (ITS) region exhibited the highest interspecific divergence, which was significantly higher than the observed intraspecific variation and showed the highest identification efficiency, followed by ITS2, psbA-trnH and, finally, rpoB. matK, rbcL, and rpoC1 performed poorly in this evaluation. ITS, ITS2, and psbA-trnH were able to perfectly identify the tested species Artemisia annua, A. absinthium, A. rupestris, A. tonurnefortiana, A. austriaca, A. dracunculus, A. vulgaris, and A. macrocephala. Therefore, we propose the ITS, ITS2, and psbA-trnH regions as promising DNA barcodes for the closely related species of Artemisia L. in Xinjiang.

Artemisia annua respon to various types of organic fertilizer and dose in lowland

Science.gov (United States)

Yunus, A.; Samanhudi; Brahmanto, N.; Widyastuti, Y.

2018-03-01

Artemisia annua belongs to asteraceae genus which has many benefits in the medical field. Artemisia contains artemisinin which is used to cure malaria disease. The obstacle of artemisia development in Indonesia is low artemisinin content and the fact that artemisia only able to grow well in the highland area. For that this experiment aimed to increase the artemisinin content through enhancing artemisia biomass in the lowland using the application of organic fertilizer. Experiment was conducted in GreenhouseLab, Faculty of Agriculture, Sebelas Maret University, Surakarta from October 2015 to January 2016. Two factor of treatment and three replications was performed during experiment. The first factor is the organic fertilizer type and the second is the application dose. Result showed that Rabbit manure at 40% application dose give best influence on the plant height (172,62 cm), number of branches (68,3 branch), flowering time (102,67 day after planted), fresh weight (56,47 g) and dry weight (43,15 g), moreover Rabbit manure at 80% dose give the best influence on the root length (27,33 cm).

Taxonomic and nomenclatural rearrangements in Artemisia subgen. Tridentatae, including a redefinition of Sphaeromeria (Asteraceae, Anthemideae)

Science.gov (United States)

Sonia Garcia; Teresa Garnatje; E. Durant McArthur; Jaume Pellicer; Stewart C. Sanderson; Joan Valles

2011-01-01

A recent molecular phylogenetic study of all members of Artemisia subgenus Tridentatae, as well as most of the other New World endemic Artemisia and the allied genera Sphaeromeria and Picrothamnus, raised the necessity of revising the taxonomic framework of the North American endemic Artemisia. Composition of the subgenus Tridentatae is enlarged to accommodate other...

Environ: E00355 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available E00355 Artemisia annua stem and leaf Crude drug Artemisinin [CPD:C09538], Artemisinic acid, Art...emisilactone, Artemisinol, Kaempferol [CPD:C05903], Coumarins, Comphene [CPD:C06076 C06304], 1,...8-Cineole [CPD:C09844], D-alpha-Cadinene [CPD:C16815], Caryophyllene epoxide [CPD:C16908], Cuminal, Artemisia alcohol, Art...phyllene [CPD:C09629], gamma-Caryophyllene Artemisia annua [TAX:35608] ... Asteraceae (daisy family) Artemisia annua stem and leaf (dried) ...

Leishmanicidal activities of Artemisia annua leaf essential oil against Visceral Leishmaniasis

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Mohammad eIslamuddin

2014-11-01

Full Text Available Visceral leishmaniasis (VL, the second-most dreaded parasitic disease after malaria, is currently endemic in 88 countries. Dramatic increases in the rates of infection, drug resistance and non-availability of safe vaccines have highlighted the need for identification of novel and inexpensive anti-leishmanial agents from natural sources. In this study, we showed the leishmanicidal effect of essential oil from Artemisia annua leaves (AALEO against Leishmania donovani in vitro and in vivo. AALEO was extracted by hydrodistillation and characterized by GC-MS, the most abundant compounds were found to be camphor (52.06 % followed by β-caryophyllene (10.95 %. AALEO exhibited significant leishmanicidal activity against L. donovani, with 50 % inhibitory concentration of 14.63 ± 1.49 µg ml-1 and 7.3 ± 1.85 µg ml─1, respectively, against the promastigotes and intracellular amastigotes. The effect was mediated through programmed cell death as confirmed by externalization of phosphatidylserine, DNA nicking by TdT-mediated dUTP nick-end labelling (TUNEL assay, dyskinetoplastidy, cell cycle arrest at sub-G0–G1 phase, loss of mitochondrial membrane potential and reactive oxygen species (ROS generation in promastigotes and nitric oxide (NO generation in ex vivo model. AALEO presented no cytotoxic effects against mammalian macrophages even at 200 µg ml─1. Intra-peritoneal administration of AALEO (200 mg/ kg.b.w. to infected BALB/c mice reduced the parasite burden by almost 90 % in the liver and spleen with significant reduction in weight. There was no hepato- or nephro-toxicity as demonstrated by normal levels of serum enzymes. The promising antileishmanial activity shown by camphor-rich AALEO may provide a new lead in the treatment of VL.

Allergy to foods in patients monosensitized to Artemisia pollen.

Science.gov (United States)

Garcia Ortiz, J C; Cosmes, P M; Lopez-Asunsolo, A

1996-12-01

It is known that patients with pollinosis may display clinical characteristics caused by allergy to certain fruits and vegetables, but subjects allergic to Artemisia seem to show particularly peculiar characteristics. The clinical features of 84 patients with rhinitis, asthma, urticaria, and/or anaphylaxis whose inhalant allergy was exclusively to Artemisia vulgaris were studied and compared with a control group of 50 patients monosensitized to grass pollen. The mean age for the beginning of symptoms was 30.2 years, and this was higher than in the control group (P history of atopia, lower than in the control group (P lettuce (two), pollen (two), beer (two), almond (one), peanut (one), other nuts (one), carrot (one), and apple (one). None of the patients monosensitized to grass had food allergy. CAP inhibition experiments were carried out on a single patient. Results showed the existence of common antigenic epitopes in pistachio and Artemisia pollen for this patient. We concluded that mugwort hay fever can be associated with the Compositae family of foods, but that it is not normally associated with other foods.

Studies of a new hybrid taxon in the Artemisia tridentata (Asteraceae: Anthemideae) complex

Science.gov (United States)

Heather D. Garrison; Leila M. Shultz; E. Durant McArthur

2013-01-01

Members of the Artemisia tridentata complex (ASTERACEAE: Anthemideae: Artemisia subgen. Tridentatae) have adapted to changing environmental conditions through geographic migration, introgression, and hybridization. These processes have resulted in morphologic and genetic variation. A presumed hybrid ("Bonneville" big sagebrush) of the complex occurs in the...

Constituents of Artemisia indica Willd. from Uttarakhand Himalaya: A source of davanone.

Science.gov (United States)

Haider, S Zafar; Mohan, Manindra; Andola, Harish Chandra

2014-07-01

The genus Artemisia is important due to its medicinal properties as well as vital aroma compounds of commercial value. The aim of the study was to explore the potential of the essential oil of Artemisia indica wildly growing in Uttarakhand. The aerial parts of Artemisia indica Willd. (Asteraceae), collected from wild growing habitat of Garhwal Himalaya, Uttarakhand (north of India) at full flowering stage were hydro-distilled and gave pale yellow oil with the yield of 0.8% (v/w). The obtained essential oil was analyzed by GC and GC-MS and identified 32 components, amounting 95.42% of the oil. Among detected compounds, the principal component was found to be davanone (30.80%), followed by β-pinene (15.30%) and germacrene-D (5.82%). To the best of our knowledge, this is the first report on A. indica from Himalayan region of India, which detected davanone as major component. The species, collected from a specific location, can be explored for isolation of davanone for its industrial utilization and as alternate source of Artemisia pallens, which have already established commercial value.

The growth response of Artemisia annua L. to organic fertilizer type in lowland

Science.gov (United States)

Prasetyo, L.; Widyastuti, Y.; Yunus, A.; Samanhudi

2018-03-01

Artemisia annua L. is a medicinal plant known in long period of time. Artemisia annua has a drug content therein, the compound is artemisinin, these compounds are useful as anti-malarial compounds. Growth of Artemisia annua L. in normal conditions is on the plateau. Planting can be done in lowland, but there is a risk that must be faced. This study was conducted to evaluate the response of the growth of the plant Artemisia annua conducted in lowland. This research was conducted at the Laboratory Jumantono of the Faculty of Agriculture, University of Sebelas Maret Surakarta. Data were analyzed using analysis of variance and if there is a significant difference continued with Duncan Multiple Range Test (DMRT) level of 5%. The results showed that the application of goat manure has a positive effect on plant height by 201.9 cm, the number of branches by 57, 30.67 ml root volume and root length of 25 cm, and weight 12.4 grams interest.

Investigation of Artemisia tridentata as a biogeochemical uranium indicator

Energy Technology Data Exchange (ETDEWEB)

Diebold, F E; McGrath, S [Montana Coll. of Mineral Science and Technology, Butte (USA)

1985-01-01

Hydroponic experiments were conducted with seedlings of Artemisia tridentata subsp. tridentata (big sagebrush) to test the effect of the phosphate speciation of uranium in solution on its uptake by big sagebrush. No single complex could be identified as being preferentially taken up by the plant, but the varying aqueous phosphate concentrations did affect uranium uptake by the plants at the higher uranium concentrations in solution. The data also substantiate the tendency for uranium to behave as an essential element in this plant species. The implications for the use of Artemisia tridentata as a biogeochemical uranium indicator are discussed.

Response of Artemisia annua L. to shade and manure fertilizer application in lowland altitude

Science.gov (United States)

Permana, H. H.; Widyastuti, Y.; Samanhudi; Yunus, A.

2018-03-01

Artemisia is a plant producing artemisinin substance which is the main compound in the treatment of malaria. Artemisia comes from China, usually grows wild in native habitats in the plains with an altitude of 1,000-1,500 meters above the sea level. Artemisia development efforts in Indonesia hampered by limited land with the required altitude due to their competition with vegetable crops. Based on this reason, this research is conducted to observe the growth of artemisia planted in lowland with the help of shade and manure. This study aims to determine the level of shade and best manure on the growth of Artemisia. Research conducted at the Laboratory of the Faculty of Agriculture UNS Jumantono using nested design with two factors, shade as main factor and manure fertilizer as sub factor. The data analysis used F test with confidence level of 5%, if significant, then continued with DMRT (Duncan Multiple Range Test). The results showed the treatment of shade gave no difference in growth within 50% shade, 75% shade as well as without shade treatment. Goat manure fertilizer gave the highest result and able to increase plant height, number of branches, flower weight and root volume.

[Essential oil from Artemisia lavandulaefolia induces apoptosis and necrosis of HeLa cells].

Science.gov (United States)

Zhang, Lu-min; Lv, Xue-wei; Shao, Lin-xiang; Ma, Yan-fang; Cheng, Wen-zhao; Gao, Hai-tao

2013-12-01

To investigate the effects of Artemisia lavandulaefolia essential oil on apoptosis and necrosis of HeLa cells. Cell viability was assayed using MTT method. The morphological and structure alterations in HeLa cells were observed by microscopy. Furthermore, cell apoptosis was measured by DNA Ladder and flow cytometry. DNA damage was measured by comet assay, and the protein expression was examined by Western blot analysis. MTT assay displayed essential oil from Artemisia lavandulaefolia could inhibit the proliferation of HeLa cells in a dose-dependent manner. After treated with essential oil of Artemisia lavadulaefolia for 24 h, HeLa cells in 100 and 200 microg/mL experiment groups exhibited the typical morphology changes of undergoing apoptosis, such as cell shrinkage and nucleus chromatin condensed. However, the cells in the 400 microg/mL group showed the necrotic morphology changes including cytomembrane rupture and cytoplasm spillover. In addition, DNA Ladder could be demonstrated by DNA electrophoresis in each experiment group. Apoptosis peak was also evident in flow cytometry in each experiment group. After treating the HeLa cells with essential oil of Artemisia lavadulaefolia for 6 h, comet tail was detected by comet assay. Moreover, western blotting analysis showed that caspase-3 was activated and the cleavage of PARP was inactivated. Essential oil from Artemisia lavadulaefolia can inhibit the proliferation of HeLa cells in vitro. Low concentration of essential oil from Artemisia lavadulaefolia can induce apoptosis, whereas high concentration of the compounds result in necrosis of HeLa cells. And,the mechanism may be related to the caspase-3-mediated-PARP apoptotic signal pathway.

Study of artemisinin and sugar accumulation in Artemisia vulgaris and Artemisia dracunculus "hairy" root cultures.

Science.gov (United States)

Drobot, Kateryna O; Matvieieva, Nadiia A; Ostapchuk, Andriy M; Kharkhota, Maxim A; Duplij, Volodymyr P

2017-09-14

We studied the effect of genetic transformation on biologically active compound (artemisinin and its co-products (ART) as well as sugars) accumulation in Artemisia vulgaris and Artemisia dracunculus "hairy" root cultures. Glucose, fructose, sucrose, and mannitol were accumulated in A. vulgaris and A. dracunculus "hairy" root lines. Genetic transformation has led in some cases to the sugar content increasing or appearing of nonrelevant for the control plant carbohydrates. Sucrose content was 1.6 times higher in A. vulgaris "hairy" root lines. Fructose content was found to be 3.4 times higher in A. dracunculus "hairy" root cultures than in the control roots. The accumulation of mannitol was a special feature of the leaves of A. vulgaris and A. dracunculus control roots. A. vulgaris "hairy" root lines differed also in ART accumulation level. The increase of ART content up to 1.02 mg/g DW in comparison with the nontransformed roots (up to 0.687 mg/g DW) was observed. Thus, Agrobacterium rhizogenes-mediated genetic transformation can be used for obtaining of A. vulgaris and A. dracunculus "hairy" root culture produced ART and sugars in a higher amount than mother plants.

IDENTIFIKASI DAN PENETAPAN KADAR SENYAWA KUMARIN DALAM EKSTRAK METANOL Artemisia Annua L. SECARA KROMATOGRAFI LAPIS TIPIS - DENSITOMETRI

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Sukmayati Alegantina

2012-08-01

Full Text Available Abstract. Artemisia annua L. contain the active compounds include: terpenoids, flavonoids, kumarin, artemisinin acid, artennuin B, phenols, saponins, and fat. Kumarin and its derivatives have biological activity that can stimulate skin pigment, blood anticoagulation and can inhibit the effects of carcinogens. With this biological activity of kumarin, the research is done to ensure there is kumarin by identification and measure kumarin level which is contained in the Artemisia annua L. herb. The analysis methods include the extraction and fractionation. Identification and determination of level with Thin-Layer Chromatography (TLC using a Densitometer CS-9301 PC. From the result of TLC identification of kumarin standard known that Artemisia annua L extract contain kumarin compound which marked by a blue spot flouresense on standards and methanol extract of artemisia annua L. seeing under UV light at a wavelength of 366 nm with Rf value of standard and sample is 0.31, the measurement of kumarin spot with Densitometer known that kumarin concentration in the extract of Artemisia annua L. is 10.5 ul/ ml with 105% RecoveryKeywords: Artemisia annua L, kumarin, TLC-Densitometry

Chemical compositions of essential oils from two Artemisia species used in Mongolian traditional medicine

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Javzmaa N

2018-02-01

Full Text Available Essential oils of aromatic and medicinal plants generally have a diverse range of activities because they possess many active constituents that work through a several modes of action. Artemisia, the largest genus of the family Asteraceae, has a number of effects against human and plant diseases. The main purpose of the present study was to investigate chemical compositions of essential oils of two Artemisia species, Artemisia palustris L and Artemisia sericea Weber ex Stechm from the Mongolian steppe zone using gas chromatography and gas chromatography-mass spectrometry. The essential oil of A.palustris was characterized by the presence of monoterpene hydrocarbons such as  trans-β-ocimene (59.1%, cis-β-ocimene (11.6% and myrcene (7.1%, while the oil of A.sericea was dominated by the presence of three oxygenated monoterpenoids as 1,8-cineole (25.8%, borneol (22.5% and camphor (18.8% which are used for preparation of a fragrance and medicinal products.

The Antioxidant Activities and Total Phenolic of Artemisia Martima, Achillea Millefolium and Matricaria Recutica

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A Mirzaei

2010-10-01

Full Text Available Introduction & Objective: Consumption of plant derived antioxidant contributes to reducing risks of certain chronic and degenerative diseases. The aim of the present study was to study the antioxidant activities and total phenolic of Artemisia Martima, Achillea Millefolium and Matricaria Recutica Materials & Methods: The present study was conducted at Yasuj University of Medical Sciences in 2009. The Stem and flower sample of plants were air-dried, and then grinded and were finally extracted by ethanol: water (70: 30 for 48 h in room temperature. Extracts were filtered and dried under vacuum system. The antioxidant activity of three ethanol extract of the medicinal plants, Artemisia martima, Achillea millefolium and Matricaria recutica, were analyzed by five different methods (1,1-diphenyl-2-picrylhydrazyl (DPPH radical, 2, 20azinobis- (3-ethylbenzthiazoline -6-sulphonic acid (ABTS radical cation,Ferric-reducing antioxidant power assay (FRAP, phosphomolybdenum (PMB and reducing power ( RP. In addition, for determination of antioxidant components, the total phenolic content was also analyzed. The collected data was analyzed by SPSS software. Results: For all antioxidant activity assays, Artemisia martima had the highest antioxidant activity value and also total phenol content. Antioxidant capacity analyses revealed that the FRAP and DPPH had comparable results. Antioxidant activity at 1 mg/mL, in ABTS were in the order Artemisia martima> Achillea millefolium> Matricaria recutica. Similar trend was observed for PMB content. RP, FRAP and DPPH were in the order Artemisia martima> Matricaria recutica > Achillea millefolium . Conclusion: The extracts showed a variety of antioxidant activities in all antioxidant assay system. This study demonstrated that Artemisia martima crude extract exhibit significant antioxidant activity.

Chemical Polymorphism of Essential Oils of Artemisia vulgaris Growing Wild in Lithuania.

Science.gov (United States)

Judzentiene, Asta; Budiene, Jurga

2018-02-01

Compositional variability of mugwort (Artemisia vulgaris L.) essential oils has been investigated in the study. Plant material (over ground parts at full flowering stage) was collected from forty-four wild populations in Lithuania. The oils from aerial parts were obtained by hydrodistillation and analyzed by GC(FID) and GC/MS. In total, up to 111 components were determined in the oils. As the major constituents were found: sabinene, 1,8-cineole, artemisia ketone, both thujone isomers, camphor, cis-chrysanthenyl acetate, davanone and davanone B. The compositional data were subjected to statistical analysis. The application of PCA (Principal Component Analysis) and AHC (Agglomerative Hierarchical Clustering) allowed grouping the oils into six clusters. AHC permitted to distinguish an artemisia ketone chemotype, which, to the best of our knowledge, is very scarce. Additionally, two rare cis-chrysanthenyl acetate and sabinene oil types were determined for the plants growing in Lithuania. Besides, davanone was found for the first time as a principal component in mugwort oils. The performed study revealed significant chemical polymorphism of essential oils in mugwort plants native to Lithuania; it has expanded our chemotaxonomic knowledge both of A. vulgaris species and Artemisia genus. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

The genus Artemisia L. in the northern region of Saudi Arabia: essential oil variability and antibacterial activities.

Science.gov (United States)

Guetat, Arbi; Al-Ghamdi, Faraj A; Osman, Ahmed K

2017-03-01

Four species of the genus Artemisia L. (Artemisia monosperma, Artemisia scoparia, Artemisia judaica and Artemisia sieberi) growing in the northern region of Saudi Arabia were investigated with respect to their volatile oil contents. The yield of oil varied between 0.30 and 0.41%, % (w/w). A. monosperma showed the highest number of compounds with 30 components representing 93.78% of oil composition. However, A. judaica showed the lowest number of compounds with only 16 components representing 87.47% of essential oil. A. scoparia and A. sieberi are both composed of 17 components, representing 97.14 and 94.2% of total oil composition. A. sieberi and A. judaica were dominated by spathulenol (30.42 and 28.41%, respectively). For A. monosperma, butanoic acid (17.87%) was a major component. However, A. scoparia was a chemotype of acenaphthene. (83.23%). Essential oil of studied species showed high antibacterial activities against common human pathogens.

Essential Oil Compositions in Artemisia scoparia Waldst

African Journals Online (AJOL)

Administrator

2012-05-22

May 22, 2012 ... Gazanchian, Ali* and Zarif Ketabi, Hamed. Department of Genetic and Physiology, Agricultural and Natural Resources Research Center of Khorasan, ..... Means with similar letters for both years are not significant (P < 0.05.). in Artemisia spp. REFERENCES. Al-Charchafchi F, Redha FM, Kamel WM (1988).

( Artemisia absinthium ) Extract On Oxidative Stress In Ameliorating ...

African Journals Online (AJOL)

exposure related disease. The aim of the study was to investigate the effect of aqueous extract of wormwood (Artemisia absinthium) on oxidative stress in rats protractedly exposed to lead. Aqueous extract of wormwood plant was administered ...

Evaluation and Selection of Mutative Artemisia (Artemisia annua L. According to the Altitude Variants

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ENDANG GATI LESTARI

2011-03-01

Full Text Available Induction of genetic variant of Artemisia annua L. was conducted through the application of gamma ray irradiation in 2007-2008. The aim was to obtain a plant with high artemisine content ≥ 0.5% and late flowering period of about ≥ 7 month after planting. Tweleve selected genotypes were subsequently examined to gain genetic stability on altitude of 1500, 950, and 540 m asl. The results showed that the plants had shorter flowering age in Cicurug (540 m asl than that of in Pacet (950 m asl and Gunung Putri (1540 m asl. Genotype 8 had the latest age of flowering in the three locations than the other genotypes, however, the growth and biomass were the lowest. Vegetative growth of Artemisia in Pacet and Gunung Putri was better than those in Cicurug. Genotype of 15 in Cicurug and 5A genotype in Gunung Putri and Pacet had higher wet and dry weight than that of two other associates. Based on plant biomass, 5 genotypes from Gunung Putri and Pacet i.e. 1D, 3, 5A, 14, and 15 genotypes were selected, as well as 5 genotypes i.e. 1D, 3, 4, 5A, and 15 genotypes from Cicurug. Analisys on artemisin content successfully obtained 5 selected somaclone lines i.e. 1B, 2, 4, 14, and 3 somaclones.

Phylogenetic analysis of Artemisia L. (Asteraceae) based on ...

African Journals Online (AJOL)

Administrator

2009-12-01

Dec 1, 2009 ... African Journal of Biotechnology Vol. 8 (23), pp. 6561-6568, 1 ... 3National Center of Excellence in Geology, University of Peshawar, Peshawar, Pakistan. Accepted 2 ... of the genus Artemisia in the South Asian region repre-.

Evaluation of artemisia mutant lines conducted from gamma irradiation treatment

International Nuclear Information System (INIS)

Ragapadmi Purnamaningsih; EG Lestari; M Syukur

2010-01-01

Cases of Malaria diseases attack in Indonesia has been increasing. Plasmodium falciparum the cause of malaria disease is now resistant to the usual medicine. One of malaria medicine which recommended by WHO is artemisinine compound extracted from Artemisia annua L plant. Low artemisinine content is one problem of Artemisia development in Indonesia. Increasing genetic variation using gamma irradiation is one alternative method to improve artemisinin content. In 2007, induce mutation had been done to artemisia seeds using gamma irradiation at dosage of 10-100 Gy. The good rooting planlet was regenerated and acclimatized in the green house, and then the seedling (M0 generation) was planted in the field at 1545 m asl. Plants derived from seeds without gamma irradiation treatment and cultured in vitro (in vitro control) were used as control. The result showed there were some morphological variations between the mutant lines (plant height, shape of the leaves and time of flowering). Ten mutant lines were selected based on biomass yield and analyzed for the artemisinine content.The result showed that artemisinine content of the mutant lines ranged from 0.44 - 1.41%, and it was significantly higher than that of in vitro control (0.43%). (author)

Genetic variability of Artemisia capillaris (Wormwood capillary) by ...

African Journals Online (AJOL)

The genetic variability among individuals of Artemisia capillaris from state of Terengganu, Malaysia was examined by using the random amplified polymorphic DNA (RAPD) technique. The samples were collected from differences regional in Terengganu State. The genomic DNA was extracted from the samples leaves.

Hypoglycemic Effect of Aqueous and Methanolic Extract of Artemisia afra on Alloxan Induced Diabetic Swiss Albino Mice

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Idris Ahmed Issa

2015-01-01

Full Text Available Diabetes mellitus is metabolic syndrome that causes disability, early death, and many other complications. Currently insulin and many synthetic drugs are used in diabetes treatment. However, these pharmaceutical drugs are too expensive particularly for sub-Saharan population in addition to their undesirable side effects. The present study was aimed to evaluate antidiabetic effect and toxicity level of Artemisia afra which was collected from its natural habitat in Bale Zone, around Goba town, 455 km southeast of Addis Ababa. Air dried aerial parts of Artemisia afra were separately extracted with both distilled water and 95% methanol. Oral acute toxicity test was conducted on healthy Swiss albino mice. Antidiabetic effect of the aqueous and methanolic extracts of Artemisia afra was separately evaluated on alloxan induced diabetic mice at doses of 500, 750, and 1000 mg/Kg body weight orally. The results indicate that mean lethal dose (LD50 for aqueous extract of Artemisia afra was 9833.4 mg/Kg. Blood glucose level was significantly decreased by 24% (p<0.005 and 56.9% (p<0.0004 in groups that received aqueous extract of Artemisia afra at dose of 500 mg/Kg and 750 mg/Kg, respectively. The methanolic extract of Artemisia afra also significantly lowered blood glucose by 49.8% (p<0.0001 at doses of 1000 mg/kg on the 5th hr. Aqueous extract of Artemisia afra was regarded as nontoxic and safe since its LD50 was found above 5000 mg/Kg. Aqueous extract showed higher effect at relatively lower dose as compared to methanolic extract. The aqueous extract was screened positive for phytochemicals like flavonoids, polyphenols, and tannins that were reported to have antioxidant activity.

Burial increases seed longevity of two Artemisia tridentata (Asteraceae) subspecies

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Wijayratne, Upekala C.; Pyke, David A.

2012-01-01

Premise of the study: Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an active role in postfire recovery of the foundation shrub Artemisia tridentata, yet conditions under which seeds persist are largely unknown. Methods: We investigated seed longevity of two Artemisia tridentata subspecies in situ by retrieving seed bags that were placed at varying depths over a 2 yr period. We also sampled naturally dispersed seeds in litter and soil immediately after seed dispersal and before flowering in subsequent seasons to estimate seed persistence. Key results: After 24 mo, seeds buried at least 3 cm below the soil surface retained 30–40% viability whereas viability of seeds on the surface and under litter declined to 0 and Artemisia tridentata has the potential to form a short-term soil seed bank that persists longer than has been commonly assumed, and that burial is necessary for seed longevity. Use of seeding techniques that promote burial of some seeds to aid in formation of a soil seed bank may increase restoration potential.

Characterization of element and mineral content in Artemisia annua ...

African Journals Online (AJOL)

Characterization of element and mineral content in Artemisia annua and Camellia sinensis leaves by handheld X-ray fluorescence. Traore Alassane, Diallo Mouhamadou, Gueye Papa El Hadji Omar, Wague Ahmadou, Lutgen Pierre, Sarr Ousmane, Mboup Souleymane ...

Drying affects artemisinin, dihydroartemisinic acid, artemisinic acid, and the antioxidant capacity of Artemisia annua L. leaves.

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Ferreira, Jorge F S; Luthria, Devanand L

2010-02-10

There is limited information on how postharvest drying of Artemisia annua affects artemisinin (ART) biosynthesis and A. annua antioxidant capacity. Antioxidants may boost the bioactivity of ART and the crop commercial value. We evaluated the effect of freeze, oven, shade, and sun drying, time of drying, and light intensity on the leaf concentration of ART, dihydroartemisinic acid (DHAA), artemisinic acid (AA), and on the leaf antioxidant capacity. Freeze-dried samples had the lowest ART concentrations as compared to the other drying methods. However, the ferric reducing antioxidant power assay showed that freeze- and oven-dried samples had similarly high antioxidant activities, which declined significantly after plants were shade- and sun-dried. Shade drying for 1, 2, and 3 weeks, under ambient or low light, did not change the ART content but significantly decreased the leaf antioxidant activity, mainly if sun-dried. A significant decrease (82% average) in DHAA was observed for all drying procedures as compared to freeze drying, with a simultaneous, significant increase in ART (33% average). The average bioconversion of DHAA to ART was 43% for oven- and shade-dried plants and 94% for sun-dried plants, reiterating the hypothesis that DHAA, not AA, is the main biosynthetic precursor of ART and suggesting that sun drying improves the bioconversion from DHAA to ART. Data also indicate that oven drying for 24 h at 45 degrees C can provide good levels of both ART and antioxidants in leaves. These findings are valuable for the commercial production of ART and of bioactive antioxidants that might synergize with the antimalarial and anticancer effects of ART when combined in traditional preparations to improve human and animal health.

Comparative analysis of ADS gene promoter in seven Artemisia ...

Indian Academy of Sciences (India)

2014-12-23

Dec 23, 2014 ... antimalarial drugs from plants that were used in traditional. Chinese medicine ...... ogy of eukaryotic promoter prediction-a review. Comput. Chem. ... Main J. J. 2006 Antiviral effect of artemisinin from Artemisia annua against a ...

Flower morphology and floral sequence in Artemisia annua (Asteraceae)

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Premise of the study: Artemisia annua produces phytochemicals possessing antimalarial, antitumor, anti-inflammatory, and anthelmintic activities. The main active ingredient, artemisinin, is extremely effective against malaria. Breeding to develop cultivars producing high levels of artemisinin can he...

Artemisia tilesii Ledeb hairy roots establishment using Agrobacterium rhizogenes-mediated transformation.

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Matvieieva, N A; Shakhovsky, A M; Belokurova, V B; Drobot, K O

2016-05-18

An efficient and rapid protocol for the establishment of Artemisia tilesii "hairy" root culture is reported. Leaf explants of aseptically growing plants were cocultured with Agrobacterium rhizogenes A4 wild strain or A. rhizogenes carrying the plasmids with nptII and ifn-α2b genes. Root formation on the explants started in 5-6 days after their cocultivation with bacterial suspension. Prolongation of explant cultivation time on the medium without cefotaxime led to stimulation of root growth. The effects of sucrose concentration as well as of the levels of synthetic indole-3-butyric acid (IBA) and native growth regulator Emistim on the stimulation of A. tilesii "hairy" root growth were studied. Maximum stimulating effect both for the control and for transgenic roots was observed in case of root cultivation on the media supplemented with IBA-up to 7.95- and 9.1-fold biomass increase, respectively. Cultivation on the medium with 10 μl/L Emistime has also led to the control roots growth stimulation (up to 2.75-fold). Emistime at 5 μl/L concentration led to 5.46-fold mass increase in only one "hairy" root line. Higher sucrose content (40 g/L) stimulated growth of two hairy root lines but had no effect on growth of the control roots.

Phellinus artemisiae sp. nov. (Basidiomycota, Hymenochaetaceae), from western USA

Czech Academy of Sciences Publication Activity Database

Vlasák, Josef; Vlasák, J.

2017-01-01

Roč. 303, č. 1 (2017), s. 93-96 ISSN 1179-3155 Institutional support: RVO:60077344 Keywords : chaparral Fungi * Phellinus artemisiae sp. nov. * molecular taxonomy * Fungi Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 1.240, year: 2016

Peptides extracted from Artemisia herba alba have antimicrobial ...

African Journals Online (AJOL)

Background: Artemisia herba alba, classified into the family of Asteraceae, is an aromatic herb that is traditionally used as a purgative and antipyretic folk medicine by rural people of south Tunisia. This study reports the first identification of antimicrobial peptides from this medicinal plant that inhibited the growth of several ...

Artemisia Extract Improves Insulin Sensitivity in Women With Gestational Diabetes Mellitus by Up-Regulating Adiponectin.

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Sun, Xia; Sun, Hong; Zhang, Jing; Ji, Xianghong

2016-12-01

Gestational diabetes mellitus (GDM) has affected a great number of pregnant women worldwide. Artemisia extracts have been found to exhibit a potent antidiabetic effect in the treatment of type 2 diabetes mellitus. We aimed to examine the effects of Artemisia extract on insulin resistance and lipid profiles in pregnant GDM patients. Patients in their second trimester were randomly assigned to the Artemisia extract group (AE) or to a placebo group (PO). They were instructed to consume either AE or PO daily for a period of 10 weeks. Glucose and insulin profiles and adiponectin level were assessed at baseline (week 0) and after the treatment (week 10). Compared to the PO group, fasting plasma glucose, serum insulin levels, homeostasis model of assessment of insulin resistance (HOMA-IR), and β-cell function (HOMA-B) were significantly reduced in the AE group participants. Moreover, levels of circulating adiponectin were also significantly up-regulated in the AE group, which also positively contributed to improved insulin sensitivity. Daily administration of Artemisia extract improves insulin sensitivity by up-regulating adiponectin in women with gestational diabetes mellitus. © 2016, The American College of Clinical Pharmacology.

Chemical Diversity and Biological Activity of the Volatiles of Five Artemisia Species from Far East Russia

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Gulmira Özek

2014-05-01

Full Text Available Artemisia argyi , A. feddei, A. gmelinii, A. manshurica, and A. olgensis (Asteraceae were collected in Far East Russia. Oils were hydrodistilled and simultaneously analyzed by GC-FID and GC/MS. Main constituents were found as follows in Artemisia oils: selin-11-en-4 a -ol (18.0%, 1,8-cineole (14.2.0%, artemisia alcohol (12.9%, borneol (9.7% in A. argyi; camphor (31.2%, 1,8-cineole (17.6%, a -thujone (5.7% in A. feddei; longiverbenone (12.0%, isopinocamphone (8.9%, 1,8-cineole (6.7%, camphor (5.8%, trans-p-menth-2-en-1-ol (5.3% in A. gmelinii; germacrene D (11.2%, rosifoliol (10.1%, caryophyllene oxide (6.8%, eudesma-4(15,7-dien-1 b -ol (5.6% in A. manshurica; eudesma-4(15,7-dien-1 b -ol (6.9%, caryophyllene oxide (5.6%, guaia-6,10(14-dien-4 b -ol (5.1% and hexadecanoic acid (5.0% in A. olgensis. Oils were subsequently submitted for antifungal and antimosquito evaluations. Artemisia species oils showed biting deterrent effects in Aedes aegypti and Artemisia gmelinii oil with the most active biting deterrence index values of 0.82 ± 0.1 at 10 m g/mL. Larval bioassay of A. gmelinii and A. olgensis oils showed higher larvicidal activity against Ae. aegypti larvae with LD50 values of 83.8 (72.6 – 95.7 ppm and 91.0 (73.8 – 114.5 ppm, respectively. Antifungal activity was evaluated against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides using direct overlay bioautography assay and all showed non-selective weak antifungal activity. Antioxidant evaluations of the oils were performed by using b -carotene bleaching, Trolox equivalent and DPPH tests. The tested Artemisia oils demonstrated moderate antioxidant activity.

Antiulcer effect of artemisia absinthium L. in rats

International Nuclear Information System (INIS)

Shafi, N.; Khan, G.A.; Ghauri, E.G.

2004-01-01

The extracts of Artemisia absinthium induced a significant decrease in volume of gastric juice, acid output and peptic activity but no effect was determined on mucin activity in acetylsalicylic acid (ASA) ulcerated rats. Moreover, they decreased the ulcer index significantly. Phytochemical analysis indicated the presence of saponins and glycosidic sugars in the extract. (author)

Engineering Isoprenoid Biosynthesis in Artemisia annua L. for the Production of Taxadiene: A Key Intermediate of Taxol

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Meiya Li

2015-01-01

Full Text Available Taxadiene is the first committed precursor to paclitaxel, marketed as Taxol, arguably the most important anticancer agent against ovarian and breast cancer. In Taxus, taxadiene is directly synthesized from geranylgeranyl diphosphate (GGPP that is the common precursor for diterpenoids and is found in most plants and microbes. In this study, Artemisia annua L., a Chinese medicinal herb that grows fast and is rich in terpenoids, was used as a genetic engineering host to produce taxadiene. The TXS (taxadiene synthase gene, cloned from Taxus and inserted into pCAMBIA1304, was transformed into Artemisia annua L. using the Agrobacterium tumefaciens-mediated method. Thirty independent transgenic plants were obtained, and GC-MS analysis was used to confirm that taxadiene was produced and accumulated up to 129.7 μg/g dry mass. However, the high expression of TXS did not affect plant growth or photosynthesis in transgenic Artemisia annua L. It is notable that artemisinin is produced and stored in leaves and most taxadiene accumulated in the stem of transgenic Artemisia annua L., suggesting a new way to produce two important compounds in one transgenic plant: leaves for artemisinin and stem for taxadiene. Overall, this study demonstrates that genetic engineering of the taxane biosynthetic pathway in Artemisia annua L. for the production of taxadiene is feasible.

Evaluation of ethanol extract of Artemisia maciverae aerial part for ...

African Journals Online (AJOL)

christy

Evaluation of ethanol extract of Artemisia maciverae aerial part for antiplasmodial activity ... median lethal dose of A. maciverae in mice was determined to be greater than ... medicinal uses [9]. ..... mode of action and mechanism of resistance.

Methanolic Extract’s Activity of Artemisia absinthium, Vitexagnus-castus and Phytolacaamericana Against Leishmania major; in vitro and in vivo

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Khanjani Jafroodi S.1 MSc,

2015-06-01

Full Text Available Aims Leishmaniasis is the most prevalent vector- borne parasitic disease in Iran. Drug treatment is the best way to treat leishmaniasis, while the common drugs are not efficient enough and inevitable side effects limit using these drugs. The aim of this study was to analyze in vitro and in vivo activity of the methanolic extract of Artemisia absinthium, Vitex agnus-castus and Phytolaca americana Against Leishmania major. Materials & Methods The methanolic extracts of Artemisia absinthium, Vitex agnuscastus and Phytolaca americana were prepared by cold percolation method. The inhibitory concentration 50 (IC50 of the plant extracts was determined against L. major promastigotes followed by efficacy evaluation of the extracts against amastigotes and in vivo assay in the BALB/c animal model. The data was analyzed with SPSS 19 software using Student’s T test and ANOVA. Findings Artemisia absinthium had the highest amount of active compounds against promastigotes of L. major (IC50=159.45 and antiprolifrative activity of Artemisia absinthium on both forms of L. major (extracellular promastigotes and intracellular amastigotes was the highest (MI=33%. Vitex agnus-castus had the least toxic effect for macrophages (8%. All extracts limited the progression of lesion size versus control group, however, only inhibitory effect of Artemisia absinthium extract was statistically significant. Conclusion Artemisia absinthium is the most effective growth inhibitor of amastigotes in animal lesions and it is safe for drug application in human and animals.

Strategies to enhance biologically active-secondary metabolites in cell cultures of Artemisia - current trends.

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Ali, Mohammad; Abbasi, Bilal Haider; Ahmad, Nisar; Khan, Haji; Ali, Gul Shad

2017-11-01

The genus Artemisia has been utilized worldwide due to its immense potential for protection against various diseases, especially malaria. Artemisia absinthium, previously renowned for its utilization in the popular beverage absinthe, is gaining resurgence due to its extensive pharmacological activities. Like A. annua, this species exhibits strong biological activities like antimalarial, anticancer and antioxidant. Although artemisinin was found to be the major metabolite for its antimalarial effects, several flavonoids and terpenoids are considered to possess biological activities when used alone and also to synergistically boost the bioavailability of artemisinin. However, due to the limited quantities of these metabolites in wild plants, in vitro cultures were established and strategies have been adopted to enhance medicinally important secondary metabolites in these cultures. This review elaborates on the traditional medicinal uses of Artemisia species and explains current trends to establish cell cultures of A. annua and A. absinthium for enhanced production of medicinally important secondary metabolites.

Antioxidant properties of volatile oils obtained from Artemisia taurica ...

African Journals Online (AJOL)

In this study, the antioxidant properties of volatile oils obtained from the earth parts of the Artemisia taurica Willd. and Salvia kronenburgii Rech. Fil. plants and their effects on xanthine oxidase enzyme were studied. The chemical contents of each volatile oil were determined by applying gas chromatograpghy-mass ...

Inhibitory Activity of Artemisia spicigera Essential Oil Against Fungal Species Isolated From Minced Meat

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Ghajarbeygi

2015-11-01

Full Text Available Background Meat is an important source of several nutrients. The capability top of fresh meat to rot, causing the group of studies food science, biological and chemical stability meat consideration. Objectives This study was conducted to examine the inhibitory effect of Artemisias spicigera essential oil against fungal species isolated from minced meat. Materials and Methods Two types of media dichloran 18% glycerol (DG18 agar and dichloran rosebengal chloramphenicol (DRBC agar were selected for the mycological analysis of the minced meat samples. To evaluate the antifungal activity of essential oils, the microdilution broth method based on the CLSI (M27A guideline was used. Results Artemisias spicigera essential oil has an inhibitory effect on the growth of fungi found in samples of minced meat. Aspergillus, Penicillium and Cladosporium were the most common genera on both medium types. Average Minimum Inhibitory Concentration 50 = 1.88 µL/mL and MIC90 = 2 µL/mL were reported. The genus of Mucor with MIC = 1.0 µL/mL was the most sensitive and Aspergilus versicolor was the most resistant species to the essential oil with MIC = 4 µL/mL. Conclusions The results of the present study show a favorable inhibitory effect of Artemisias spicigera essential oil on fungal growth, especially Aspergillus species. According to the results, antifungal components of Artemisias spicigera in different forms are used to prevent fungal pollution.

Detecting the differences in responses of stomatal conductance to moisture stresses between deciduous shrubs and Artemisia subshrubs.

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Gao, Qiong; Yu, Mei; Zhou, Chan

2013-01-01

Shrubs and subshrubs can tolerate wider ranges of moisture stresses in both soil and air than other plant life forms, and thus represent greater nonlinearity and uncertainty in ecosystem physiology. The objectives of this paper are to model shrub/subshrub stomatal conductance by synthesizing the field leaf gas exchanges data of 24 species in China, in order to detect the differences between deciduous shrubs and Artemisia subshrubs in their responses of stomatal conductance to changes in the moisture stresses. We revised a model of stomatal conductance by incorporating the tradeoff between xylem hydraulic efficiency and cavitation loss risk. We then fit the model at the three hierarchical levels: global (pooling all data as a single group), three functional groups (deciduous non-legume shrubs, deciduous legume shrubs, and subshrubs in Artemisia genus), and individual observations (species × sites). Bayesian inference with Markov Chain Monte Carlo method was applied to obtain the model parameters at the three levels. We found that the model at the level of functional groups is a significant improvement over that at the global level, indicating the significant differences in the stomatal behavior among the three functional groups. The differences in tolerance and sensitivities to changes in moisture stresses are the most evident between the shrubs and the subshrubs: The two shrub groups can tolerate much higher soil water stress than the subshrubs. The analysis at the observation level is also a significant improvement over that at the functional group level, indicating great variations within each group. Our analysis offered a clue for the equivocal issue of shrub encroachment into grasslands: While the invasion by the shrubs may be irreversible, the dominance of subshrubs, due to their lower resistance and tolerance to moisture stresses, may be put down by appropriate grassland management.

Optimization for ultrasound-assisted extraction of polysaccharides with chemical composition and antioxidant activity from the Artemisia sphaerocephala Krasch seeds.

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Zheng, Quan; Ren, Daoyuan; Yang, Nana; Yang, Xingbin

2016-10-01

Artemisia sphaerocephala Krasch seeds polysaccharides have been reported to have a variety of important biological activities. However, effective extraction of Artemisia sphaerocephala Krasch seeds polysaccharides is still an unsolved issue. In this study, the orthogonal rotatable central composite design was employed to optimize ultrasound-assisted extraction conditions of Artemisia sphaerocephala Krasch seeds polysaccharides. Based on a single-factor analysis method, ultrasonic power, extraction time, solid-liquid ratio and extraction temperature were shown to significantly affect the yield of polysaccharides extracted from the A. sphaerocephala Krasch seeds. The optimal conditions for extraction of Artemisia sphaerocephala Krasch seeds polysaccharides were determined as following: ultrasonic power 243W, extraction time 125min, solid-liquid ratio 64:1 and extraction temperature 64°C, where the experimental yield was 14.78%, which was well matched with the predicted value of 14.81%. Furthermore, ASKP was identified as a typical heteropolysaccharide with d-galacturonic acid (38.8%) d-galactose (20.2%) and d-xylose (15.5%) being the main constitutive monosaccharides. Moreover, Artemisia sphaerocephala Krasch seeds polysaccharides exhibited high total reducing power and considerable scavenging activities on DPPH, hydroxyl and superoxide radicals, in a concentration-dependent manner in vitro. Copyright © 2016 Elsevier B.V. All rights reserved.

In vitro and in vivo anthelmintic activity of extracts from Artemisia parviflora and A. sieversiana

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Irum S.

2017-09-01

Full Text Available In the northern areas of Pakistan, the use of Artemisia based therapeutics is a common practice. Plants of genus Artemisia are known to possess anthelmintic and therapeutic effect. Infections caused by gastrointestinal nematodes are major threat to livestock industry across the world resulting in loss of production and indirect economic losses due to high cost of anthelmintic drugs. Present study was carried out to evaluate in vitro and in vivo effect of Artemisia sieversiana and Artemisia parviflora on Haemonchus contortus, a parasitic nematode of small ruminants. Methanolic plant extract was tested against three different developmental stages using an egg hatch assay, infective larvae and adult worm motility assay. Different concentrations were used for the bioassays and post exposure mortality was recorded after 8 hr for adult worms and infective larvae, while egg inhibition percentage was observed after 27 hr. A highly significant ability to inhibit the egg hatching (100 % was recorded for both plant extracts while, the highest activity for adult worm assay and larvicidal assay was 90 % for A. sieversiana. The highest activity for adult motility and larvicidal assay for A. parviflora was 89 % and 86.6 % respectively. For in vivo trials maximum parentage reduction was 77.0 % for A. sieversiana and 73.6 % for A. parviflora. It is concluded that selected plant extracts were effective in reducing worm burden in animals.

ISOLASI DAN IDENTIFIKASI ARTEMISININ DARI HERBA Artemisia annua L .

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Sukmayati Alegantina

2012-07-01

Full Text Available Abstract. Malaria is still a major problem in Indonesia, because mortality in patients with severe malaria remains high. Many cases are occurs in endemic areas (e.g. Papua,Kalimantan, Bali and Sulawesi. Chloroquin is the most common antimalarial drug which is widely used since 1934. Plasmodium falciparum resistant to chloroquine was reported in some countries (e.g. Thailand, Vietnam, Indonesia, and Bangladesh. To delay the development of resistance, WHO recommended antimalarial combination therapy. Artemisinin and its derivatives (artesunate, artemether, dihydroartemisin produce rapid clearance of parasitemia and rapid resolution of symptoms compare with chloroquine. Artemisinin is obtained from Artemisia annua L. Even though there are some research produced a chemical synthetic of artemisinin, but it is not efficient and notstable. Our purposes are to conduct a preliminary research to obtain a method of isolation and identification of artemisinin which is the first step to develop a raw material of artemisinin as antimalarial drug in Indonesia.The first step of isolation is extraction from herb Artemisia annua L with n-hexane thatproduced n-hexane extract, this process is well-known as soxhletation. The second step isidentification of chemical substances from n-hexane extract. The third step is to obtain isolate from n-hexane extract by fractionation with acetonitril and separation with column chromatography. The last step is chemical and physical identification of isolateby TLC (Thin Layer (Chromatography and FT-IR.The result from n-hexane extract measurement is 4.33 % and from acetonitril fraction is2. 40 %. Chemical identification of n-hexan extract found there are terpenoid, phenol, flavonoid, fatty acid, atsiri oil and saponin. Organoleptic identification of isolate is white crystal, monosubstrate, odorless and bitter. Identification of isolate with TLC and FT-IR confirmed that the isolate is artemisinin.Keywords: artemisinin, Artemisia

Cytotoxicity of Dorema auchri, Achillea millefolium and Artemisia aucheri by Artemia

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M Ghavamizadeh

2013-09-01

Full Text Available Abstract Background & aim: Nowadays, toxic compounds derived from plants used against microbes and cancer cells. The aim of this study was to evaluate cytotoxicity of Dorema aucheri, Achillea millefollium and Artemisia aucheri using brine shrimp, Artemia urmiana, lethality test. Methods: In this experimental study, the plants were collected from the Kohgiluyeh and Boyer-Ahmad Province, then identified by a botanist. Clean and air-dried aerial parts of plants were extracted with suitable solvents. Cytotoxicity evaluation was performed using larvae hatched cysts were purchased from Urmia. Live larvae were exposed to different concentrations of extract and the numbers of live and dead larvae were counted after 24 hours. Mean of LC 50 of any extracts from control and exposed live larvae were examined. The data were analyzed using the Finney’s Probit analysis. Results: Hydro ethanol and chloroform extracts of Achillea millefolium, Dorema aucheri and Artemisia aucheri exhibited potent brine shrimp lethality with LC50 67.8±0.53μg.ml-1, 76.50±0.60μg.ml-1, 92.70±6.05μg.ml-1 respectively. The degree of lethality was found to be directly proportional to the concentration of extracts. Conclusion: According to BSLT, LC50 of D. aucheri, A. millefolium and A. aucheri, they were considered as toxic. So these plants could be a source of new compounds with biological activity. Key words: Artemia urmiana, Dorema auchri, Achillea millefolium, Artemisia aucheri, Cytotoxicity

Essential oil from Artemisia phaeolepis: chemical composition and antimicrobial activities.

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Ben Hsouna, Anis; Ben Halima, Nihed; Abdelkafi, Slim; Hamdi, Naceur

2013-01-01

Artemisia phaeolepis, a perennial herb with a strong volatile odor, grows on the grasslands of Mediterranean region. Essential oil obtained from Artemisia phaeolepis was analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. A total of 79 components representing 98.19% of the total oil were identified, and the main compounds in the oil were found to be eucalyptol (11.30%), camphor (8.21%), terpine-4-ol (7.32%), germacrene D (6.39), caryophyllene oxide (6.34%), and caryophyllene (5.37%). The essential oil showed definite inhibitory activity against 10 strains of test microorganisms. Eucalyptol, camphor, terpine-4-ol, caryophyllene, germacrene D and caryophyllene oxide were also examined as the major components of the oil. Camphor showed the strongest antimicrobial activity; terpine-4-ol, eucalyptol, caryophyllene and germacrene D were moderately active and caryophyllene oxide was weakly active. The study revealed that the antimicrobial properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components.

Artemisia communities in arid zones of Uzbekistan (Central Asia)

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Lyubov A. Kapustina; Montserrat Torrell; Joan Valles

2001-01-01

Central Asia, and particularly the former Soviet Middle Asian countries, with more than 180 taxa (45 endemics), is one of the centers of origin and speciation of the genus Artemisia L. (Asteraceae, Anthemideae). Several species of this genus, mainly belonging to subgenus Seriphidium (Besser) Rouy, are shrubs that dominate the landscape and form large communities in...

Evaluation of antimalarial, free-radical-scavenging and insecticidal activities of Artemisia scoparia and A. Spicigera, Asteraceae

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Fariba H. Afshar

2011-12-01

Full Text Available Artemisia species (Asteraceae, widespread throughout the world, are a group of important medicinal plants. The extracts of two medicinal plants of this genus, Artemisia scoparia Waldst. & Kit. and A. spicigera C. Koch, were evaluated for potential antimalarial, free-radical-scavenging and insecticidal properties, using the heme biocrystallisation and inhibition assay, the DPPH assay and the contact toxicity bioassay using the pest Tribolium castaneum, respectively. The methanol extracts of both species showed strong free-radical-scavenging activity and the RC50 values were 0.0317 and 0.0458 mg/mL, respectively, for A. scoparia and A. spicigera. The dichloromethane extracts of both species displayed a moderate level of potential antimalarial activity providing IC50 at 0.778 and 0.999 mg/mL for A. scoparia and A. spicigera, respectively. Both species of Artemisia showed insecticidal properties. However, A. spicigera was more effective than A. scoparia.

Antiparasitic efficacy of Artemisia absinthium, toltrazuril and amprolium against intestinal coccidiosis in goats.

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Iqbal, A; Tariq, K A; Wazir, V S; Singh, R

2013-04-01

Various anti-protozoal dugs have been popularly used in the treatment of goat coccidiosis; however, residual effects are well noticed in host animals. The present study was undertaken with the objective to evaluate the anticoccidial efficacy of Artemisia absinthium, as a safe alternative in comparison to two conventional anticoccidial drugs (toltrazuril and amprolium) in goats (Capra hircus) naturally infected with Eimeria spp. (>5,000 oocyst per gram of faeces). Goat kids (1-3 month old, 10 kg body weight) were randomly allocated into five groups (eight kids each). Group A was negative for coccidiosis and was retained as uninfected and untreated (negative control). Group B was infected and was kept untreated (positive control). Group C was given a single oral dose of toltrazuril (Baycox 5 %) at 20 mg kg(-1) BW (IM). Group D received amprolium soluble powder 20 w/w% at 50 mg kg(-1) BW 5 days daily. Group E was given a single dose of ethanolic extract of Artemisia absinthium at 2 g kg(-1) BW. Clinical signs, body-weight gain (BWG) and number of oocysts per gram faeces (OPG) were monitored daily for 30 days post treatment (DPT). The OPG was highly reduced as early as 7 DPT and there was a marked improvement in body weight gain (7 DPT) and faster clinical recovery (3-6 DPT) in the toltrazuril treated kids compared to amprolium and Artemisia absinthium treated groups (P ≤ 0.05). In Artemisia absinthium treated kids, the oocysts continued to be in faeces up to 28th day post treatment indicating that ethanolic extract of herb was less efficacious against caprine coccidiosis as compared to amprolium and toltrazuril. From the observations of the present study it can be concluded that control of goat coccidiosis through single treatment of toltrazuril was highly effective as compared to the other two treatments. However, integrated control involving pasture management, chemical and herbal control will be a more realistic and sustainable means of

Quality, energy requirement and costs of drying tarragon (Artemisia dracunculus L)

NARCIS (Netherlands)

ArabHosseini, A.

2005-01-01

Tarragon ( Artemisia dracunculus L.) is a favorite herbal and medicinal plant. Drying is necessary to achieve longer shelf life with high quality, preserving the original flavor. Essential oil content and color are the most important parameters that define the quality of herbal and medicinal plants.

Flavonoids from the aerial parts of Artemisia biennis Willd

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M. Mojarrab*

2017-11-01

Full Text Available Background and objectives: The genus Artemisia contains over 250 species all over the world. A. biennis Willd is one of the species which grows wildly in Iran. Camphor and (E-beta-farnesene have been reported as the major components of the essential oil from A. biennis. In spite of the presence of a rather wide range of reported bioactivities there is no previous phytochemical study on  A. biennis. Methods: The plant was collected from Zoshk (Khorasan Razavi province, Iran. Extraction was done by maceration method using petroleum ether, dichloromethane, ethyl acetate, ethanol and equal amounts of water and ethanol (hydroethanolic extract, respectively. A combination of solid phase extraction (SPE and high pressure liquid chromatography (HPLC of the hydroethanolic extract was used to purify the compounds. Structures of the isolated compounds were elucidated by spectroscopic means, including MS and 1HNMR. Results: Three known flavonoids, luteolin, kaempferol and apigenin were isolated and identified from the hydroethanolic extract. Conclusion: Our results are in good agreement with dominant presence of derivatives of the flavones luteolin and apigenin in the genus Artemisia which has been previously reported .

Potential ecological roles of artemisinin produced by Artemisia annua L.

Science.gov (United States)

Knudsmark Jessing, Karina; Duke, Stephen O; Cedergreeen, Nina

2014-02-01

Artemisia annua L. (annual wormwood, Asteraceae) and its secondary metabolite artemisinin, a unique sesquiterpene lactone with an endoperoxide bridge, has gained much attention due to its antimalarial properties. Artemisinin has a complex structure that requires a significant amount of energy for the plant to synthesize. So, what are the benefits to A. annua of producing this unique compound, and what is the ecological role of artemisinin? This review addresses these questions, discussing evidence of the potential utility of artemisinin in protecting the plant from insects and other herbivores, as well as pathogens and competing plant species. Abiotic factors affecting the artemisinin production, as well as mechanisms of artemisinin release to the surroundings also are discussed, and new data are provided on the toxicity of artemisinin towards soil and aquatic organisms. The antifungal and antibacterial effects reported are not very pronounced. Several studies have reported that extracts of A. annua have insecticidal effects, though few studies have proven that artemisinin could be the single compound responsible for the observed effects. However, the pathogen(s) or insect(s) that may have provided the selection pressure for the evolution of artemisinin synthesis may not have been represented in the research thus far conducted. The relatively high level of phytotoxicity of artemisinin in soil indicates that plant/plant allelopathy could be a beneficial function of artemisinin to the producing plant. The release routes of artemisinin (movement from roots and wash off from leaf surfaces) from A. annua to the soil support the rationale for allelopathy.

The Genus Artemisia: A 2012–2017 Literature Review on Chemical Composition, Antimicrobial, Insecticidal and Antioxidant Activities of Essential Oils

Science.gov (United States)

Singh, Pooja

2017-01-01

Essential oils of aromatic and medicinal plants generally have a diverse range of activities because they possess several active constituents that work through several modes of action. The genus Artemisia includes the largest genus of family Asteraceae has several medicinal uses in human and plant diseases aliments. Extensive investigations on essential oil composition, antimicrobial, insecticidal and antioxidant studies have been conducted for various species of this genus. In this review, we have compiled data of recent literature (2012–2017) on essential oil composition, antimicrobial, insecticidal and antioxidant activities of different species of the genus Artemisia. Regarding the antimicrobial and insecticidal properties we have only described here efficacy of essential oils against plant pathogens and insect pests. The literature revealed that 1, 8-cineole, beta-pinene, thujone, artemisia ketone, camphor, caryophyllene, camphene and germacrene D are the major components in most of the essential oils of this plant species. Oils from different species of genus Artemisia exhibited strong antimicrobial activity against plant pathogens and insecticidal activity against insect pests. However, only few species have been explored for antioxidant activity. PMID:28930281

The Genus Artemisia: a 2012–2017 Literature Review on Chemical Composition, Antimicrobial, Insecticidal and Antioxidant Activities of Essential Oils

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Abhay K. Pandey

2017-09-01

Full Text Available Essential oils of aromatic and medicinal plants generally have a diverse range of activities because they possess several active constituents that work through several modes of action. The genus Artemisia includes the largest genus of family Asteraceae has several medicinal uses in human and plant diseases aliments. Extensive investigations on essential oil composition, antimicrobial, insecticidal and antioxidant studies have been conducted for various species of this genus. In this review, we have compiled data of recent literature (2012–2017 on essential oil composition, antimicrobial, insecticidal and antioxidant activities of different species of the genus Artemisia. Regarding the antimicrobial and insecticidal properties we have only described here efficacy of essential oils against plant pathogens and insect pests. The literature revealed that 1, 8-cineole, beta-pinene, thujone, artemisia ketone, camphor, caryophyllene, camphene and germacrene D are the major components in most of the essential oils of this plant species. Oils from different species of genus Artemisia exhibited strong antimicrobial activity against plant pathogens and insecticidal activity against insect pests. However, only few species have been explored for antioxidant activity.

Chemical Analysis of Essential oil of "Artemisia haussknechtii Boiss" by GC and GC/ MS

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A. Nassir- Ahraadi . A. Rustaiyan

1994-08-01

Full Text Available The composition of the essential oil from the leaves and flowers of "Artemisia haussknechtii Boiss growing wild in the north-west of Iran, was investigated by GC and GC/MS."nThe main components of the volatile oil were 1,8 - cineol (16.5%, camphor (14.1%. artemisia ketone (10.5%, fragranol (9.0%, Yomogi alcohol (7.5% and B- pinene (5.4%. The total contribution of these compounds to the oil amounted to 63.0%."nMonoterpens and sesquiterpenes represent 90.08% and 1.52% of the oil respectively. Of the twenty oxygen-containing monoterpenes which made up a fairly large fraction of the terpenoid composition, the predominant components were 1,8 - cineole and camphor.

Establishing Artemisia tridentata ssp wyomingensis on mined lands: Science and economics

Energy Technology Data Exchange (ETDEWEB)

Schuman, G.E.; Vicklund, L.E.; Belden, S.E. [ARS, Cheyenne, WY (United States). High Plains Grasslands Research Station

2005-12-01

In 1996, the Wyoming Department of Environmental Quality enacted regulations governing the reestablishment of woody shrubs on mined lands. The regulation required that an average density of one shrub m{sup -2} be reestablished on at least 20% of the disturbed land area and that the shrub composition must include dominant premine species. In Wyoming, and much of the Northern Great Plains, that meant that Artemisia tridentata Nutt. ssp. wyomingensis (Beetle and Young) (Wyoming big sagebrush) had to be reestablished on mined lands. Artemisia tridentata Nutt. ssp. wyomingensis had proven difficult to reestablish on mined lands because of poor quality seed, seed dormancy and a poor understanding of the seedbed ecology of this species. Research in the last two decades has produced significant knowledge in the area of direct-seed establishment of Artemisia tridentata Nutt. ssp. wyomingensis on mined lands. Our research has shown that reducing grass seeding rates will reduce competition and result in larger sagebrush plants that are more likely to survive and provide greater structural diversity to the plant community. Economic analyses demonstrated that big sagebrush can be established at a cost of $0.01-0.05 per seedling using direct seeding methods compared to transplanting nursery grown seedlings, estimated to cost $0.72-$1.65 per seedling (depending on size) to grow and from $1.30-$2.40 to plant (flat land to 2:1 slopes). An adequate level of precipitation will be necessary to ensure successful establishment of this species no matter what method of propagation is selected and direct seeding gives greater opportunity for success because of the demonstrated longevity of the seed to germinate 3-5 years after the initial seeding.

Interactive effects of moss-dominated crusts and Artemisia ordosica on wind erosion and soil moisture in Mu Us sandland, China.

Science.gov (United States)

Yang, Yongsheng; Bu, Chongfeng; Mu, Xingmin; Shao, Hongbo; Zhang, Kankan

2014-01-01

To better understand the effects of biological soil crusts (BSCs) on soil moisture and wind erosion and study the necessity and feasibility of disturbance of BSCs in the Mu Us sandland, the effects of four treatments, including moss-dominated crusts alone, Artemisia ordosica alone, bare sand, and Artemisia ordosica combined with moss-dominated crusts, on rainwater infiltration, soil moisture, and annual wind erosion were observed. The major results are as follows. (1) The development of moss-dominated crusts exacerbated soil moisture consumption and had negative effects on soil moisture in the Mu Us sandland. (2) Moss-dominated crusts significantly increased soil resistance to wind erosion, and when combined with Artemisia ordosica, this effect became more significant. The contribution of moss-dominated crusts under Artemisia ordosica was significantly lower than that of moss-dominated crusts alone in sites where vegetative coverage > 50%. (3) Finally, an appropriate disturbance of moss-dominated crusts in the rainy season in sites with high vegetative coverage improved soil water environment and vegetation succession, but disturbance in sites with little or no vegetative cover should be prohibited to avoid the exacerbation of wind erosion.

Effects of light and drought stress on germination of Artemisia sieberi ...

African Journals Online (AJOL)

Preservation and development of plant cover are major factors in the management of range ecosystems. Artemisia sieberi is one of the native dominant species of vast areas in the Irano-Turanian bioclimatic region. This species is very tolerant to drought stress and grazing pressure. Therefore, it can be used to rehabilitate ...

Loss of artemisinin produced by Artemisia annua L. to the soil environment

Science.gov (United States)

Artemisia annua L. synthesizes and accumulates the secondary metabolite artemisinin, a compound with antimalarial properties. As cultivation of the plant is still the only cost effective source of artemisinin, the production takes place in monocultures of A. annua. Artemisinin is known to have inse...

The Nociceptive and Anti-Inflammatory Effects of Artemisia dracunculus L. Aqueous Extract on Fructose Fed Male Rats

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Shahraki Mohammad Reza

2015-01-01

Full Text Available Aim & Objective. Artemisia dracunculus L. (Tarragon species have been used as a traditional medicine. The present study was designed to evaluate the nociceptive and anti-inflammatory effects of A. dracunculus L. leaf aqueous extract on fructose drinking water (FDW in male rats. Materials & Methods. Forty-eight Wistar-albino male rats weighing 200–250 g were divided into control (C, control extract (CE, FDW, and FDWE groups (n=12. Group C did not receive any agents; Group CE did 100 mg/kg A. dracunculus L. aqueous extract on a daily basis for duration of four weeks. FDW Group received fructose drinking water (10%, weight/volume but did not receive any agents during trial period. FDWE group received 100 mg/kg A. dracunculus L. aqueous extract during trial period. At the end of experiment, a biphasic pain response was induced following interplanetary injection of formalin (50 µL, 1%. Obtained data were analyzed using SPSS software version 17 and using ANOVA and Tukey post hoc tests. Results were expressed as mean ± SE. Statistical differences were considered significant at P<0.05. Results. Our findings revealed that acute and chronic pain scores in FDW group are significantly higher than other ones and A. dracunculus L. aqueous extract causes significant decreasing of this parameter in FDWE group (P<0.001. Moreover, IL6 and TNF values in this group were significantly decreased compared to FDW group (P<0.05. Conclusion. Results in the present study show that FDW causes the pain response score to increase and cause proinflammatory cytokines in rat model but A. dracunculus L. leaf aqueous extract improves values of these parameters.

Dendrochronology of Atriplex portulacoides and Artemisia maritima in Wadden Sea salt marshes

NARCIS (Netherlands)

Decuyper, M.; Slim, P.A.; Loon-Steensma, van J.M.

2014-01-01

The study uses a rather unusual method, dendrochronology, to investigate the growth and survival of Atriplex portulacoides L. and Artemisia maritima L. on salt marshes at two field sites on the Dutch North Sea barrier islands of Terschelling and Ameland. By providing information on longevity of

Exploration and classification of chromatographic fingerprints as additional tool for identification and quality control of several Artemisia species.

Science.gov (United States)

Alaerts, Goedele; Pieters, Sigrid; Logie, Hans; Van Erps, Jürgen; Merino-Arévalo, Maria; Dejaegher, Bieke; Smeyers-Verbeke, Johanna; Vander Heyden, Yvan

2014-07-01

The World Health Organization accepts chromatographic fingerprints as a tool for identification and quality control of herbal medicines. This is the first study in which the distinction, identification and quality control of four different Artemisia species, i.e. Artemisia vulgaris, A. absinthium, A. annua and A. capillaris samples, is performed based on the evaluation of entire chromatographic fingerprint profiles developed with identical experimental conditions. High-Performance Liquid Chromatography (HPLC) with Diode Array Detection (DAD) was used to develop the fingerprints. Application of factorial designs leads to methanol/water (80:20 (v/v)) as the best extraction solvent for the pulverised plant material and to a shaking bath for 30 min as extraction method. Further, so-called screening, optimisation and fine-tuning phases were performed during fingerprint development. Most information about the different Artemisia species, i.e. the highest number of separated peaks in the fingerprint, was acquired on four coupled Chromolith columns (100 mm × 4.6 mm I.D.). Trifluoroacetic acid 0.05% (v/v) was used as mobile-phase additive in a stepwise linear methanol/water gradient, i.e. 5, 34, 41, 72 and 95% (v/v) methanol at 0, 9, 30, 44 and 51 min, where the last mobile phase composition was kept isocratic till 60 min. One detection wavelength was selected to perform data analysis. The lowest similarity between the fingerprints of the four species was present at 214 nm. The HPLC/DAD method was applied on 199 herbal samples of the four Artemisia species, resulting in 357 fingerprints. The within- and between-day variation of the entire method, as well as the quality control fingerprints obtained during routine analysis, were found acceptable. The distinction of these Artemisia species was evaluated based on the entire chromatographic profiles, developed by a shared method, and visualised in score plots by means of the Principal Component Analysis (PCA) exploratory data

Characterization and comparison of transgenic Artemisia annua GYR and wild-type NON-GYR plants in an environmental release trial.

Science.gov (United States)

Liu, H; Wu, G G; Wang, J B; Wu, X; Bai, L; Jiang, W; Lv, B B; Pan, A H; Jia, J W; Li, P; Zhao, K; Jiang, L X; Tang, X M

2016-08-26

The anti-malarial drug, artemisinin, is quite expensive as a result of its slow content in Artemisia annua. Recent investigations have suggested that genetic engineering of A. annua is a promising approach to improve the yield of artemisinin. In this study, the transgenic A. annua strain GYR, which has high artemisinin content, was evaluated in an environmental release trial. First, GYR plants were compared with the wild-type variety NON-GYR, with regard to phenotypic characters (plant height, crown width, stem diameter, germination rate, leaf dry weight, 1000-seed weight, leave shape). Second, stress resistance in the two varieties (salt, drought, herbicide, and cold resistance) was evaluated under different experimental conditions. Finally, gene flow was estimated. The results indicated that there were significant differences in several agronomic traits (plant height, stem diameter, and leave dry weight) between the transgenic GYR and NON-GYR plants. Salt stress in transgenic and control plants was similar, except under high NaCl concentrations (1.6%, w/w). Leaf water, proline, and MDA content (increased significantly) were significantly different. Transgenic A. annua GYR plants did not grow better than NON-GYR plants with respect to drought and herbicide resistance. The two varieties maintained vitality through the winter. Third, gene flow was studied in an environmental risk trial for transgenic GYR. The maximum gene flow frequency was 2.5%, while the maximum gene flow distance was 24.4 m; gene flow was not detected at 29.2 m at any direction. Our findings may provide an opportunity for risk assessment in future commercialization of transgenic A. annua varieties.

Molecular Cloning and Characterization of a Broad Substrate Terpenoid Oxidoreductase from Artemisia annua

NARCIS (Netherlands)

Ryden, Anna-Margareta; Ruyter-Spira, Carolien; Litjens, Ralph; Takahashi, Shunji; Quax, Wim; Osada, Hiroyuki; Bouwmeester, Harro; Kayser, Oliver

From Artemisia annua L., a new oxidoreductase (Red 1) was cloned, sequenced and functionally characterized. Through bioinformatics, heterologous protein expression and enzyme substrate conversion assays, the elucidation of the enzymatic capacities of Red1 was achieved. Red1 acts on monoterpenoids,

Molecular cloning and characterization of a broad substrate terpenoid oxidoreductase from Artemisia annua.

NARCIS (Netherlands)

Ryden, A.M.; Ruyter-Spira, C.P.; Litjens, R.; Takahashi, S.; Quax, W.J.; Osada, H.; Bouwmeester, H.J.; Kayser, O.

2010-01-01

From Artemisia annua L., a new oxidoreductase (Red 1) was cloned, sequenced and functionally characterized. Through bioinformatics, heterologous protein expression, and enzyme substrate conversion assays, the elucidation of the enzymatic capacities of Red1 was achieved. Red1 acts on monoterpenoids,

Artemisia annua L.: agro-techniques for semi-arid environments

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Marcello Scarcella

2011-09-01

Full Text Available Artemisia annua L. is an aromatic annual plant native in Asia, probably in China, and is widespread in all temperate regions. Aerial parts contain aromatic volatile oils and non-volatile sesquiterpenes used in pharmacopoeia. The most important sesquiterpene is artemisinin and its derivatives, which are used as a remedy against malaria. In the Mediterranean region, interest in cultivating Artemisia resulted in emerging industrial activities demanding local biomass with high content of artemisinin to start new production chains. The goal of this paper was to find out appropriate agro-techniques for semi-arid climate regions to be followed by local growers in order to get convenient yield in terms of biomass and artemisinin content. The specific research objectives were to test germplasm and to develop a pilot model for A. annua, including the main agro-techniques (plant density, nitrogen supply and irrigation requirements. Results were obtained after a two-year field study carried out in an area of Salento region. The effects of the season and of the tested cultivars were not significant. The highest biomass production (36 t ha-1 of dry biomass, associated with a high percentage of artemisinin (0.97 % on dry weight, was achieved by using 7.3 plant m-2, and by supplying 60 Kg N ha-1 and 150 mm of irrigation water.

Loss of essential oil of tarragon (Artemisia dranunculus L.) due to drying

NARCIS (Netherlands)

ArabHosseini, A.; Padhye, S.; Beek, van T.A.; Boxtel, van A.J.B.; Huisman, W.; Posthumus, M.A.; Müller, J.

2006-01-01

The effect of hot air-drying on the essential oil constituents and yield in French and Russian tarragon (Artemisia dracunculus L.) leaves was studied. The tarragon leaves were dried at air temperatures ranging from 40 to 90 °C. The drying stopped when the moisture content of the samples reached 10%

In vivo evaluation of antiparasitic effects of Artemisia abrotanum and Salvia officinalis extracts on Syphacia obvelata, Aspiculoris tetrapetra and Hymenolepis nana parasites

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Mahdi Amirmohammadi

2014-02-01

Full Text Available Objective: To evaluate the effects of Salvia officinalis and Artemisia abrotanum extracts against digestive system parasites of mice. Methods: The ethanol extract was prepared and dissolved in distilled water. The mebendazole was used as positive control and distilled water as negative control. After counting eggs per gram feces, infected mice with 16 eggs per gram feces contained two to three parasites of Syphacia obvelata, Aspicoloris terepetra and Hymenolipis nana designated in 4 groups. The first group was given extracts of Artemisia (150 mg/kg, the second group was given Salvia extract (150 mg/kg, the third group was given mebendazole (10 mg/kg and finally the fourth group was given distilled water (2 mL/kg. Results: The ethanol extracts of Artemisia and Salvia plants reduced the number of parasite eggs per gram of feces. Results showed significant reduction (P-value<0.001 in the number of eggs excreted by Hymenolepis nana, Aspiculuris tetraptera, Syphacia obvelata in mice. Conclusions: These results revealed that antiparasitic effects of Artemisia and Salvia are reasonable and these two plants might be used as antiparasitic natural products.

PRODUCTION OF THE NEW ANTIMALARIAL DRUG ARTEMISININ IN SHOOT CULTURES OF ARTEMISIA-ANNUA L

NARCIS (Netherlands)

WOERDENBAG, HJ; LUERS, JFJ; VANUDEN, W; PRAS, N; MALINGRE, TM; ALFERMANN, AW

From aseptically grown Artemisia annua plantlets, shoot cultures were initiated. Using different concentrations of auxine, cytokinine and sucrose, a suitable culture medium was developed, with respect to the growth of the shoots and their artemisinin accumulation. Nitrate concentration and

GABA-A Receptor Modulation and Anticonvulsant, Anxiolytic, and Antidepressant Activities of Constituents from Artemisia indica Linn

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Imran Khan

2016-01-01

Full Text Available Artemisia indica, also known as “Mugwort,” has been widely used in traditional medicines. However, few studies have investigated the effects of nonvolatile components of Artemisia indica on central nervous system’s function. Fractionation of Artemisia indica led to the isolation of carnosol, ursolic acid, and oleanolic acid which were evaluated for their effects on GABA-A receptors in electrophysiological studies in Xenopus oocytes and were subsequently investigated in mouse models of acute toxicity, convulsions (pentylenetetrazole induced seizures, depression (tail suspension and forced swim tests, and anxiety (elevated plus maze and light/dark box paradigms. Carnosol, ursolic acid, and oleanolic acid were found to be positive modulators of α1β2γ2L GABA-A receptors and the modulation was antagonized by flumazenil. Carnosol, ursolic acid, and oleanolic acid were found to be devoid of any signs of acute toxicity (50–200 mg/kg but elicited anticonvulsant, antidepressant, and anxiolytic activities. Thus carnosol, ursolic acid, and oleanolic acid demonstrated CNS activity in mouse models of anticonvulsant, antidepressant, and anxiolysis. The anxiolytic activity of all three compounds was ameliorated by flumazenil suggesting a mode of action via the benzodiazepine binding site of GABA-A receptors.

Effect of Drying on the Color of Tarragon (Artemisia dracunculus L.) Leaves

NARCIS (Netherlands)

ArabHosseini, A.; Padhye, S.; Huisman, W.; Boxtel, van A.J.B.; Müller, J.

2011-01-01

The effect of drying conditions on the color of tarragon (Artemisia dracunculus L.) leaves was studied. Tarragon leaves were dried at temperatures of 40 to 90 °C with a constant airflow of 0.6 m/s. The samples were collected at 7%, 10%, 20%, and 30% moisture content wet basis for evaluation of the

Attempting to restore mountain big sagebrush (Artemisia tridentata ssp. vaseyana) four years after fire

Science.gov (United States)

Restoration of shrubs is increasingly needed throughout the world because of altered fire regimes, anthropogenic disturbance, and over-utilization. The native shrub mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana (Rydb.) Beetle) is a restoration priority in western North America be...

Seasonal soil CO2 flux under big sagebrush (Artemisia tridentata Nutt.)

Science.gov (United States)

Michael C. Amacher; Cheryl L. Mackowiak

2011-01-01

Soil respiration is a major contributor to atmospheric CO2, but accurate landscape-scale estimates of soil CO2 flux for many ecosystems including shrublands have yet to be established. We began a project to measure, with high spatial and temporal resolution, soil CO2 flux in a stand (11 x 25 m area) of big sagebrush (Artemisia tridentata Nutt.) at the Logan, Utah,...

Terpenoid Profile of Artemisia Alba is Related to Endogenous Cytokinins in Vitro

Czech Academy of Sciences Publication Activity Database

Krumova, S.; Motyka, Václav; Dobrev, Petre; Todorova, M.; Trendafilova, A.; Evstatieva, L.; Danova, K.

2013-01-01

Roč. 19, č. 2 (2013), s. 26-30 ISSN 1310-0351 R&D Projects: GA ČR(CZ) GAP506/11/0774 Institutional research plan: CEZ:AV0Z50380511 Keywords : Artemisia alba * in vitro * endogenous cytokinins Subject RIV: EF - Botanics Impact factor: 0.136, year: 2012 http://www.agrojournal.org/19/02-06s.pdf

Artemisinin and sesquiterpene precursors in dead and green leaves of Artemisia annua L. crops

NARCIS (Netherlands)

Lommen, W.J.M.; Elzinga, S.; Verstappen, F.W.A.; Bouwmeester, H.J.

2007-01-01

This paper analyses the accumulation and concentrations of the antimalarial artemisinin in green and dead leaves of Artemisia annua crops in two field experiments. Concentration differences were analysed as being determined by (a) the total production of artemisinin plus its upstream precursors

Compositional Characters and Antimicrobial Potential of Artemisia stricta Edgew. f. stricta Pamp. Essential Oil

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N Manika

2016-01-01

Full Text Available Chemical and biological investigations were carried out to evaluate the composition and anti-microbial potential of a rare Artemisia species viz. Artemisia stricta Edgew. f. stricta Pamp. essential oil for the first time. GC and GC/MS analysis resulted in the identification of 27 compounds, which constituted 93.2% volatile constituents of the oil. The major constituents were capillene (41.6%, spathulenol (14.6% and β-caryophyllene (13.4%. The oil was also assayed to determine its antimicrobial potential against eight bacterial and six fungal strains. The oil exhibited both antifungal and antibacterial activities. Among bacteria, the oil was most effective against Staphylococcus epidermidis (MIC 0.625 mg/mL followed by Staphylococcu. Aureus (MIC 1.25 mg/mL . While among fungi, the oil was most effective against Aspergillus flavus followed by Aspergillus niger and Sporothrix schenckii with MIC as low as 0.625 mg/mL.

Treatment of Cutaneous Leishmaniasis in Murine Model by Hydro Alcoholic Essence of Artemisia sieberi

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A Doroodgar

2008-12-01

Full Text Available Background: Considering the prevalence of leishmaniasis in Iran and many side effects associated with pentavalent antimony compounds use in its treatment, this study was designed to evaluate the effect of Artemisia sieberi essence on the experimental ulcers of cutaneous leishmaniasis on BALB/c mice."nMethods: This experimental research was performed to determine the effect of various concentrations of  Artemisia essence in BALB/c mice previously infected with active Leishmania major promastigote. A total of 50 infected BALB/c mice were randomly divided into 5 groups. Three groups (30 mice were used in the experimental condi­tions and the others were assigned as the control groups. The experimental groups received 1%, 3% and 5% of Ar­temisia, respectively. One of the control groups received ethanol 80% and the other received no treatment. The drug was administered by dropping the liquid on the top lesions, three times daily for maximum of 30 d. Every 10 days the ulcers diameter were measured and sampled for amastigote in all groups. Ulcers diameter changes were deter­mined by statistical tests."nResults: After 30 days, diameter of CL lesions increased in 1%, 3% and 5% Artemisia concentrations and the control groups. Ulcers got bigger with the more concentration. Treatments could not reduce the diameter or caused small lesions. In addition, the mice direct smears in microscopic studies were positive."nConclusion: To find the effective concentration and the mechanism of the effectiveness of the drug, further investi­gations with less concentrates of A. sieberi essence are recommended.

Treatment of Cutaneous Leishmaniasis in Murine Model by Hydro Alcoholic Essence of Artemisia sieberi

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A Doroodgar

2008-12-01

Full Text Available Background: Considering the prevalence of leishmaniasis in Iran and many side effects associated with pentavalent antimony compounds use in its treatment, this study was designed to evaluate the effect of Artemisia sieberi essence on the experimental ulcers of cutaneous leishmaniasis on BALB/c mice.Methods: This experimental research was performed to determine the effect of various concentrations of  Artemisia essence in BALB/c mice previously infected with active Leishmania major promastigote. A total of 50 infected BALB/c mice were randomly divided into 5 groups. Three groups (30 mice were used in the experimental condi­tions and the others were assigned as the control groups. The experimental groups received 1%, 3% and 5% of Ar­temisia, respectively. One of the control groups received ethanol 80% and the other received no treatment. The drug was administered by dropping the liquid on the top lesions, three times daily for maximum of 30 d. Every 10 days the ulcers diameter were measured and sampled for amastigote in all groups. Ulcers diameter changes were deter­mined by statistical tests.Results: After 30 days, diameter of CL lesions increased in 1%, 3% and 5% Artemisia concentrations and the control groups. Ulcers got bigger with the more concentration. Treatments could not reduce the diameter or caused small lesions. In addition, the mice direct smears in microscopic studies were positive.Conclusion: To find the effective concentration and the mechanism of the effectiveness of the drug, further investi­gations with less concentrates of A. sieberi essence are recommended.

The solid-state fermentation of Artemisia capillaris leaves with Ganoderma lucidum enhances the anti-inflammatory effects in a model of atopic dermatitis.

Science.gov (United States)

Son, Hyeong-U; Lee, Seul; Heo, Jin-Chul; Lee, Sang-Han

2017-05-01

Artemisia capillaris, which belongs to the Asteraceae family and the genus Artemisia, has been reported to exert inhibitory effects on diabetes, cancer and inflammation. In this study, in order to enhance the bioactivity potential of the leaves of Artemisia by Ganoderma lucidum mycelium, we prepared aqueous samples of Artemisia capillaris (Ac) leaves, Ganoderma lucidum (Gl) and aqueous fractions produced by the solid fermentation of Ganoderma lucidum on Artemisia capillaris leaves (afAc/Gl). Thereafter, we evaluated whether these samples have potential to attenuate inflammation-related symptoms in an amimal model of 2,4-dinitrofluorobenzene (DNFB)-induced atopic dermatitis. We found that afAc/Gl exhibited enhanced anti-inflamamatory activity following the solid fermentation process when compared with Ac or Gl on ear thickness, ear epidermal thickness and eosinophil infiltration in the skin tissues. The expression of nitric oxide (NO) synthases (NOSs) was measured by immunohistochemical staining. The results revealed that afAc/Gl decreased endothelial NOS and inducible NOS expression compared with the DNFB group, while neuronal NOS expression was not altered. By comparing NO production, we found that as opposed to Ac, afAc/Gl has potential to inhibit atopic dermatitis-related symptoms during the inflammatory event. As regards matrix metalloproteinase (MMP) expression patterns, afAc/Gl exerted potent inhibitory activity on the mRNA expression of MMP-2, -7, -9, -12, -14 and -19. Taken together, these results suggest that the solid state fermentation of Ac by Gl is an effective strategy to obtaining useful ingredients which are converted into valuable compounds during an atopic inflammatory insult.

Sesquiterpene Lactones from Artemisia Genus: Biological Activities and Methods of Analysis

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Bianca Ivanescu

2015-01-01

Full Text Available Sesquiterpene lactones are a large group of natural compounds, found primarily in plants of Asteraceae family, with over 5000 structures reported to date. Within this family, genus Artemisia is very well represented, having approximately 500 species characterized by the presence of eudesmanolides and guaianolides, especially highly oxygenated ones, and rarely of germacranolides. Sesquiterpene lactones exhibit a wide range of biological activities, such as antitumor, anti-inflammatory, analgesic, antiulcer, antibacterial, antifungal, antiviral, antiparasitic, and insect deterrent. Many of the biological activities are attributed to the α-methylene-γ-lactone group in their molecule which reacts through a Michael-addition with free sulfhydryl or amino groups in proteins and alkylates them. Due to the fact that most sesquiterpene lactones are thermolabile, less volatile compounds, they present no specific chromophores in the molecule and are sensitive to acidic and basic mediums, and their identification and quantification represent a difficult task for the analyst. Another problematic aspect is represented by the complexity of vegetal samples, which may contain compounds that can interfere with the analysis. Therefore, this paper proposes an overview of the methods used for the identification and quantification of sesquiterpene lactones found in Artemisia genus, as well as the optimal conditions for their extraction and separation.

Artemisinin, related sesquiterpenes, and essential oil in artemisia-annua during a vegetation period in vietnam

NARCIS (Netherlands)

Woerdenbag, HJ; Pras, N; CHAN, NG; BANG, BT; Bos, R; van Uden, W; Y, PV; BOI, NV; Batterman, S; LUGT, CB

The active principle of Artemisia annua L., artemisinin, is currently being developed to a registered antimalarial drug. For production purposes, plants with a high artemisinin content are required. We followed the development of the artemisinin content and of the biosynthetically related

Flavonoids casticin and chrysosplenol D from Artemisia annua L. inhibit inflammation in vitro and in vivo

Czech Academy of Sciences Publication Activity Database

Li, Y.J.; Guo, Y.; Yang, Q.; Weng, X. G.; Yang, L.; Wang, Y.J.; Chen, Y.; Zhang, D.; Li, Q.; Liu, X.C.; Kan, X.X.; Chen, X.; Zhu, X.X.; Kmoníčková, E.; Zídek, Zdeněk

2015-01-01

Roč. 286, č. 3 (2015), s. 151-158 ISSN 0041-008X Institutional support: RVO:68378041 Keywords : Artemisia annua L. * Flavonoids * Casticin * Chrysosplenol D * Inflammation Subject RIV: EC - Immunology Impact factor: 3.847, year: 2015

Abiotic and biotic influences on Bromus tectoreum invasion and Artemisia tridentata recovery after fire

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Lea Condon; Peter J. Weisberg; Jeanne C. Chambers

2011-01-01

Native sagebrush ecosystems in the Great Basin (western USA) are often invaded following fire by exotic Bromus tectorum (cheatgrass), a highly flammable annual grass. Once B. tectorum is established, higher fire frequencies can lead to local extirpation of Artemisia tridentata ssp. vaseyana (mountain big sagebrush) and have cascading effects on sagebrush ecosystems and...

Thionation of Essential Oils from Algerian Artemisia Herba-alba L. and Ruta Montana L.: Impact on their Antimicrobial and Insecticidal Activities

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Nassiba Fekhar

2017-12-01

Full Text Available Essential oils were extracted from Artemisia herba-alba L. and Ruta montana L. by means of steam distillation and thionated with a reagent combination of phosphorus pentasulfide and sodium bicarbonate. Both parent essential oils and their modified ones were screened for their biological and insecticidal activities. The results showed that essential oils were composed mainly of ketones; essential oils from Artemisia herba-alba L. and those from Ruta montana L. consisted of bicyclic monoterpenes and acyclic aliphatic ketones (thujone, camphor and 2-undecanone, respectively. The antimicrobial activity of essential oils was substantially improved upon thionation (from 10 to 34 mm and from 11 to 32 mm. The insecticidal effect of the thionated essential oil from Ruta montana L. was observed to be very significant, but that of the essential oil from Artemisia herba-alba L. was observed to decrease (from 100% to 70% after 24 hrs. The extracted essential oils as well as their thionated forms were characterized by GC-MS, FT-IR, and UV-visible.

Isolation and characterization of three new monoterpene synthases from Artemisia annua

OpenAIRE

Ju-Xin eRuan; Jian-Xu eLi; Xin eFang; Ling-Jian eWang; Wen-Li eHu; Xiao-Ya eChen; Changqing eYang

2016-01-01

Artemisia annua, an annual herb used in traditional Chinese medicine, produces a wealth of monoterpenes and sesquiterpenes, including the well-known sesquiterpene lactone artemisinin, an active ingredient in the treatment for malaria. Here we report three new monoterpene synthases of A. annua. From a glandular trichome cDNA library, monoterpene synthases of AaTPS2, AaTPS5 and AaTPS6, were isolated and characterized. The recombinant proteins of AaTPS5 and AaTPS6 produced multiple products with...

Antidiabetic effects of Artemisia sphaerocephala Krasch. gum, a novel food additive in China, on streptozotocin-induced type 2 diabetic rats.

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Xing, Xiao-Hui; Zhang, Zheng-Mao; Hu, Xin-Zhong; Wu, Rui-Qin; Xu, Chao

2009-09-25

Since ancient times, practicians of traditional Chinese medicine have discovered that Artemisia sphaerocephala Krasch. (Asteraceae) seed powder was useful for the treatment of diabetes. Artemisia sphaerocephala Krasch. gum (ASK gum), which is extracted from seed powder of the plant, is a novel food additive favored by the food industry in China. The objective of this study was to determine the antidiabetic function of ASK gum on type 2 diabetes. Type 2 diabetic rat model was induced with high fat diet and low dose of streptozotocin (STZ). The effects of ASK gum on hyperglycemia, hyperlipemia, insulin resistance, and liver fat accumulation in type 2 diabetic rats were evaluated. The results were compared to those of normal rats and diabetic rats treated with metformin. The addition of ASK gum to the rats' food supply significantly lowered fasting blood glucose, glycated serum protein, serum cholesterol, and serum triglyceride in type 2 diabetic rats, and significantly elevated liver glucokinase, liver glycogen, and serum high density protein cholesterol in the diabetic rats. ASK gum significantly reduced insulin resistance and liver fat accumulation of type 2 diabetes. Artemisia sphaerocephala Krasch. gum can alleviate hyperglycemia, hyperlipemia and insulin resistance of type 2 diabetes.

Chemical Composition and Insecticidal Activity against Sitophilus zeamais of the Essential Oils of Artemisia capillaris and Artemisia mongolica

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Zhi Long Liu

2010-04-01

Full Text Available In our screening program for new agrochemicals from local wild plants, Artemisia capillaris and A. mongolica were found to possess insecticidal activity against the maize weevil, Sitophilus zeamais. The essential oils of aerial parts of the two plants were obtained by hydrodistillation and were investigated by GC and GC-MS. The main components of A. capillaris essential oil were 1,8-cineole (13.75%, germacrene D (10.41%, and camphor (8.57%. The main constituents of A. mongolica essential oil were α-pinene (12.68%, germacrene D (8.36%, and γ-terpinene (8.17%. Essential oils of A. capillaris and A. mongolica possess fumigant toxicity against S. zeamais adults with LC50 values of 5.31 and 7.35 mg/L respectively. The essential oils also show contact toxicity against S. zeamais adults with LD50 values of 105.95 and 87.92 mg/adult, respectively.

ANALYSIS OF ARTEMISININ AND RELATED SESQUITERPENOIDS FROM ARTEMISIA-ANNUA L BY COMBINED GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

NARCIS (Netherlands)

WOERDENBAG, HJ; PRAS, N; BOS, R; VISSER, JF; HENDRIKS, H; MALINGRE, TM

1991-01-01

The sesquiterpenoid artemisinin (3) and its biosynthetic precursors arteannuic acid (1), arteannuin B (2) and artemisitene (4) can be separated and identified by combined gas chromatography/mass spectrometry both as a mixture of reference standards as well as in extracts of Artemisia annua L. From

Use of UV absorption for identifying subspecies of Artemisia tridentata

International Nuclear Information System (INIS)

Spomer, G.G.; Henderson, D.M.

1988-01-01

Use of UV absorption spectra for identifying subspecies of Artemisia tridentata Nutt. was investigated by analyzing the relative optical densities of alcohol extracts from herbarium and fresh plant material at 240 nm, 250 nm, and 265 nm. In all but 1 comparison, mean relative optical densities were significantly different (p=0.95) between subspecies, but intraplant and intrasubspecies variation and overlap was found to be too large to permit use of UV absorbance alone for identifying individual specimens. These results held whether dry or fresh leaves were extracted, or whether methanol or ethanol was used as the extracting solvent. (author)

Big sagebrush (Artemisia tridentata) in a shifting climate context: Assessment of seedling responses to climate

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Martha A. Brabec

2014-01-01

The loss of big sagebrush (Artemisia tridentata) throughout the Great Basin Desert has motivated efforts to restore it because of fire and other disturbance effects on sagebrush-dependent wildlife and ecosystem function. Initial establishment is the first challenge to restoration, and appropriateness of seeds, climate, and weather variability are factors that may...

Study on effect of Artemisia sieberi hydro-alcoholic extract on the survival of Lactobacillus acidophilus and Bifidobacterium lactis in probiotic yoghurt

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Saeed Akbari

2017-05-01

Full Text Available Background and Aim: In the present study, the possibility of probiotic yoghurt production using Artemisia sieberi hydro- alcoholic extract and also the effects of different concentrations of this medicinal herb on the survival of two probiotic strains, Lactobacillus acidophilus and Bifidobacterium lactis, in probiotic yoghurt were investigated. Materials and Methods: In different treatments, the amounts of 0, 0.1, 0.2, 0.3 and 0.4 gr/lit of Artemisia sieberi extract together with conventional yoghurt starter, Bif. lactis and lact. acidophilus were added to 1 liter of boiled milk. The samples were incubated at 37˚centigrade, and then, the acidity and pH changes every two hours during the incubation period were examined up to approximately 80˚ of the survival of probiotic bacteria was tested during the storage of the samples in the refrigerator. On the tenth day, after yoghurt production, all the samples were examined for sensory evaluation using a panel test and the obtained data was analyzed by means of SPSS software (V:19. Results: There was no significant difference in the acidity and pH changes during the production process of probiotic yoghurt in different treatments. The probiotic yoghurt containing 0.4 gr/lit  of Artemisia hydro-alcoholic extract had the best quality in terms of organoleptic properties and shelf life of the product. During 21 days storage in the refrigerator none of the treatments showed the number of probiotic bacteria less than 106 bacteria in gram. Conclusion: It was found that appropriate concentrations of Artemisia sieberi extract can be used for the production of probiotic yoghurt, as a new functional food containing Lactobacillus acidophilus and Bifodobacterium lactis.

Essential oil composition of four Artemisia species from Ethiopia

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N. Asfaw

2015-01-01

Full Text Available The essential oil composition of four Artemisia species, namely A. schimperi Sch. Bip. ex Engl. A. abyssinica Sch. Bip. ex A. Rich., A. afra Jacq. ex Willd., and A. absinthium L. (previously called A. rehan from Ethiopia has been studied. The essential oil obtained from A. absinthium (seedling from Europe grown in two places in Ethiopia (Addis Ababa and Butajira was also analyzed for comparison. Morphological study on the leaves of A. absinthium L. from Ethiopia (previously called A. rehan and A. absinthium (from Europe was also conducted. The essential oils were obtained by hydrodistillation using a Clevenger apparatus and analyzed by capillary GC and GC/MS. Forty three compounds representing 76 to 94% of the oils were identified. The composition of the essential oils of A. schimperi, A. afra and A. abyssinica are mainly dominated by irregular monoterpenes: yogomi alcohol (13.5-37.6%, artemisyl acetate (12.7-35.5%, and artemisia ketone (2.3-13.2%. The composition of the oil of A. absinthium (previously A. rehan however, differs from the other three species in having camphor (21.2-28.3% and davanone (21.3-26.5% as major components. The composition of A. absinthum (Europe was found to have β-thujone (42.3-66.4% and chamazulene (11.3-24.2% as major components. The study indicated that the composition of the essential oil of A. absinthium (previously A. rehan is not only different from the other three species but also from A. absinthium from Europe and does not belong to any of the chemotypes described for the species in the literature. The morphological study on the leaves also showed that it differs from that of A. absinthium from Europe. DOI: http://dx.doi.org/10.4314/bcse.v29i1.11

Chemical Composition of the Essential Oil from Artemisia arborescens L. Growing Wild in Algeria

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Gilles Figuérédo

2010-01-01

Full Text Available Essential oil extracted from dried aerial part of Artemisia arborescens L. collected from Bejaïa (Algeria, was analyzed by gas chromatography-flame ionization detector (GC-FID and gas chromatography coupled to mass spectrometry (GC-MS. The main constituents of the essential oil were chamazulene (30.2%, β-thujone (27.8%, β-eudesmol (8.1% and catalponol (5.5%.

Artemisia vulgaris pollen allergoids digestibility in the simulated conditions of the gastrointestinal tract

OpenAIRE

RATKO M. JANKOV; NATALIJA DJ. POLOVIC; MARIJA DJ. GAVROVIC-JANKULOVIC; LIDIJA BURAZER; DANICA DJERGOVIC-PETROVIC; OLGA VUCKOVIC; OLIKA DROBNJAK; ZORICA SPORCIC; MARINA ATANASKOVIC-MARKOVIC; RATKO M. JANKOV

2006-01-01

Chemically modified allergens (allergoids) have found use in both traditional and novel forms of immunotherapy of allergic disorders. Novel forms of immunotherapy include local allergen delivery, via the gastrointestinal tract. This study conveys the gastrointestinal stability of three types ofmugwort pollen allergoids under simulated conditions of the gut. Allergoids of the pollen extract of Artemisia vulgaris were obtained by means of potassium cyanate, succinic and maleic anhydride. Gastro...

A molecular phylogenetic approach to western North America endemic Artemisia and allies (Asteraceae): Untangling the sagebrushes

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Sonia Garcia; E. Durant McArthur; Jaume Pellicer; Stewart C. Sanderson; Joan Valles; Teresa Garnatje

2011-01-01

Premise of the study: Artemisia subgenus Tridentatae plants characterize the North American Intermountain West. These are landscape-dominant constituents of important ecological communities and habitats for endemic wildlife. Together with allied species and genera (Picrothamnus and Sphaeromeria), they make up an intricate series of taxa whose limits are uncertain,...

A status review on the pharmacological implications of Artemisia absinthium: A critically endangered plant

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Mubashir Hussain

2017-03-01

Full Text Available Medicinal plants are the nature’s gift for the humanity to treat various diseases and to spend a prosperous healthy life. There are almost 500 species of Artemisia. Among them, Artemisia absinthium (A. absinthium which is commonly known as wormwood is a well-known herb. It is mentioned in almost all the herbal medicinal books of the Western world. The aim of this review article is to gather information about A. absinthium which is currently scattered in form of various publications. Through this review article tried to attract the attention of people for therapeutic potential of A. absinthium. The present review comprises upto date information of active ingredients, up and down in absinthe, controversy, essential oil, traditional uses, in vitro production of secondary metabolites for pharmaceutical, pharmacology such as antitumor, neurotoxic, neuroprotective, hepatoprotective, antimalarial, anthelminitc, antipyretic, antidepressant, antiulcer, antioxidant, antibacterial, antiprotozoal and challenges of A. absinthium. Some progress has been made, but still consistent efforts are required to explore the individual compounds isolated from A. absinthium to validate and understand its traditional uses and clinical practices. This review article provides preliminary information and gives a direction for the basic and clinical research on A. absinthium (wormwood.

Quantitative determination of flavonoids by column high-performance liquid chromatography with mass spectrometry and ultraviolet absorption detection in Artemisia afra and comparative studies with various species of Artemisia plants.

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Avula, Bharathi; Wang, Yan-Hong; Smillie, Troy J; Mabusela, Wilfred; Vincent, Leszek; Weitz, Frans; Khan, Ikhlas A

2009-01-01

A simple and specific analytical method for the quantitative determination of flavonoids from the aerial parts of the Artemisia afra plant samples was developed. By column high-performance liquid chromatography (HPLC) with UV absorption and mass spectrometry (MS) detection, separation was achieved on a reversed-phase octadecylsilyl (C18) column with water, methanol, and acetonitrile, all containing 0.1% acetic acid, as the mobile phase. These methods were used to analyze various species of Artemisia plant samples. The wavelength used for quantification of flavonoids with the diode array detector was 335 nm. The limits of detection (LOD) by HPLC/MS were found to be 7.5, 7.5, 10, 2.0, and 2.0 ng/mL; and by LC-UV the LODs were 500, 500, 500, 300, and 300 ng/mL for apigenin, chrysoeriol, tamarixetin, acacetin, and genkwanin, respectively. The HPLC/MS method was found to be 50-150 times more sensitive than the HPLC-UV method. HPLC/MS coupled with an electrospray ionization interface is described for the identification and quantification of flavonoids in various plant samples. This method involved the use of the [M+H]+ ions of the compounds at mass-to-charge ratio of 1.0606, 301.0712, 317.0661, 285.0763, and 285.0763 (calculated mass), respectively, in the positive ion mode with extractive ion monitoring.

Flowering branches cause injuries to second-year main stems of Artemisia tridentata nutt. subspecies tridentata

Science.gov (United States)

Lance S. Evans; Angela Citta; Stewart C. Sanderson

2012-01-01

Eccentricity of stems of Artemisia tridentata Nutt. (big sagebrush) has been reported previously. Analysis of samples observed over 2 years documented that each stem terminal produces about 8-10 branches each year, and during second-year growth, 3-8 of these develop into short, flowering, determinate branches. Each flowering branch produces hundreds of seeds and then...

[Allelopathic effects of Artemisia sacrorum population in typical steppe based on niche theory].

Science.gov (United States)

Wang, Hui; Xie, Yong-Sheng; Cheng, Ji-Min; She, Xiao-Yan

2012-03-01

By using modified Levins niche width index and Pianka niche overlap index, this paper analyzed the ecological competition between constructive and dominant species in a typical steppe. The stem- and leaf extracts from the constructive species (Artemisia sacrorum) were utilized to study their allelopathic potential on the seed germination and plant growth of the dominant species (Stipa bungeana, Thymus mongolicus, S. grandis, and Leymus secalinus), and the ecological position of A. sacrorum in the steppe succession. In the steppe, S. bungeana had the widest niche width (0.99), followed by T. mongolicus (0.94), A. sacrorum (0.82), S. grandis (0.76), and L. secalinus (0.73). The niche overlap value between A. sacrorum and S. bungeana, S. bungeana and T. mongolicus, T. mongolicus and S. grandis, and A. sacrorum and T. mongolicus was 0.90, 0.95, 0.94, and 0.86, respectively. The allelopathic effects of A. sacrorum extracts varied with their concentration. For the seed germination, root growth, and shoot growth of the dominant species, A. sacrorum extracts showed a trend of promoting at low concentrations and inhibiting at high concentrations. The extracts of A. sacrorum had a stronger promotion effect on the root growth of S. bungeana than on that of T. mongolicus, but a stronger inhibition effect on the shoot growth of T. mongolicus than on that of S. bungeana. Methanol extracts had stronger allelopathic effects than aqueous extracts. The high niche overlap between A. sacrorum and S. bungeana, and T. mongolicus and S. grandis indicated that the steppe community would continue succession to S. bungeana, while A. sacrorum population was only an important transitional stage during the succession. The allelopathic effect of A. sacrorum played a driving role in the succession process.

Antibacterial and antioxidant activities of the essential oil of Artemisia echegarayi Hieron. (Asteraceae Actividad antibacteriana y antioxidante del aceite esencial extraído de Artemisia echegarayi Hieron. (Asteraceae

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A. Laciar

2009-12-01

Full Text Available Artemisia echegarayi Hieron. (Asteraceae is commonly known in Argentina as “ajenjo”. Many studies report high efficacy of essential oils against food-borne pathogenic bacteria. The antimicrobial activity and minimal inhibitory concentration of A. echegarayi essential oil were evaluated against seven bacterial species of significant importance in food hygiene, by using the disc diffusion assay and the micro-well dilution method, respectively. Volatile components of the extract were analyzed by gas chromatography-mass spectrometry and major components were determined. Furthermore, the essential oil was tested for its antioxidant activity. The essential oil inhibited the growth of gram-positive and gram-negative tested bacteria, with the exception of Proteus mirabilis. A. echegarayi essential oil presented the lowest minimal inhibitory concentration against Listeria monocytogenes and Bacillus cereus. Two terpenes, thujone and camphor, were identified from this essential oil as the principal constituents responsible for antibacterial activity. The oil showed a free radical scavenging activity equivalent to 50% of the reference compound. These preliminary studies showed promising results since this essential oil may provide an alternative to promote its use as a natural food additive.Artemisia echegarayi Hieron. (Asteraceae, conocida como “ajenjo”, es una planta típica de la región de Cuyo (Argentina. En este trabajo se evaluó la actividad antimicrobiana in vitro y la concentración inhibitoria mínima del aceite esencial extraído de sus partes aéreas frente a especies bacterianas que con frecuencia contaminan los alimentos. Se utilizaron las técnicas de difusión con discos en agar y microdilución en placa respectivamente. Además, se determinó la actividad antioxidante de este aceite esencial in vitro por espectrofotometría. En general, tanto las bacterias gram-positivas como las gram-negativas fueron inhibidas por este aceite, con

Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups.

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Reich, Peter B; Walters, Michael B; Ellsworth, David S; Vose, James M; Volin, John C; Gresham, Charles; Bowman, William D

1998-05-01

Based on prior evidence of coordinated multiple leaf trait scaling, we hypothesized that variation among species in leaf dark respiration rate (R d ) should scale with variation in traits such as leaf nitrogen (N), leaf life-span, specific leaf area (SLA), and net photosynthetic capacity (A max ). However, it is not known whether such scaling, if it exists, is similar among disparate biomes and plant functional types. We tested this idea by examining the interspecific relationships between R d measured at a standard temperature and leaf life-span, N, SLA and A max for 69 species from four functional groups (forbs, broad-leafed trees and shrubs, and needle-leafed conifers) in six biomes traversing the Americas: alpine tundra/subalpine forest, Colorado; cold temperate forest/grassland, Wisconsin; cool temperate forest, North Carolina; desert/shrubland, New Mexico; subtropical forest, South Carolina; and tropical rain forest, Amazonas, Venezuela. Area-based R d was positively related to area-based leaf N within functional groups and for all species pooled, but not when comparing among species within any site. At all sites, mass-based R d (R d-mass ) decreased sharply with increasing leaf life-span and was positively related to SLA and mass-based A max and leaf N (leaf N mass ). These intra-biome relationships were similar in shape and slope among sites, where in each case we compared species belonging to different plant functional groups. Significant R d-mass -N mass relationships were observed in all functional groups (pooled across sites), but the relationships differed, with higher R d at any given leaf N in functional groups (such as forbs) with higher SLA and shorter leaf life-span. Regardless of biome or functional group, R d-mass was well predicted by all combinations of leaf life-span, N mass and/or SLA (r 2 ≥ 0.79, P morphological, chemical and metabolic traits.

Leaf-IT: An Android application for measuring leaf area.

Science.gov (United States)

Schrader, Julian; Pillar, Giso; Kreft, Holger

2017-11-01

The use of plant functional traits has become increasingly popular in ecological studies because plant functional traits help to understand key ecological processes in plant species and communities. This also includes changes in diversity, inter- and intraspecific interactions, and relationships of species at different spatiotemporal scales. Leaf traits are among the most important traits as they describe key dimensions of a plant's life history strategy. Further, leaf area is a key parameter with relevance for other traits such as specific leaf area, which in turn correlates with leaf chemical composition, photosynthetic rate, leaf longevity, and carbon investment. Measuring leaf area usually involves the use of scanners and commercial software and can be difficult under field conditions. We present Leaf-IT, a new smartphone application for measuring leaf area and other trait-related areas. Leaf-IT is free, designed for scientific purposes, and runs on Android 4 or higher. We tested the precision and accuracy using objects with standardized area and compared the area measurements of real leaves with the well-established, commercial software WinFOLIA using the Altman-Bland method. Area measurements of standardized objects show that Leaf-IT measures area with high accuracy and precision. Area measurements with Leaf-IT of real leaves are comparable to those of WinFOLIA. Leaf-IT is an easy-to-use application running on a wide range of smartphones. That increases the portability and use of Leaf-IT and makes it possible to measure leaf area under field conditions typical for remote locations. Its high accuracy and precision are similar to WinFOLIA. Currently, its main limitation is margin detection of damaged leaves or complex leaf morphologies.

Optimal balance of water use efficiency and leaf construction cost with a link to the drought threshold of the desert steppe ecotone in northern China.

Science.gov (United States)

Wei, Haixia; Luo, Tianxiang; Wu, Bo

2016-09-01

In arid environments, a high nitrogen content per leaf area (Narea) induced by drought can enhance water use efficiency (WUE) of photosynthesis, but may also lead to high leaf construction cost (CC). Our aim was to investigate how maximizing Narea could balance WUE and CC in an arid-adapted, widespread species along a rainfall gradient, and how such a process may be related to the drought threshold of the desert-steppe ecotone in northern China. Along rainfall gradients with a moisture index (MI) of 0·17-0·41 in northern China and the northern Tibetan Plateau, we measured leaf traits and stand variables including specific leaf area (SLA), nitrogen content relative to leaf mass and area (Nmass, Narea) and construction cost (CCmass, CCarea), δ(13)C (indicator of WUE), leaf area index (LAI) and foliage N-pool across populations of Artemisia ordosica In samples from northern China, a continuous increase of Narea with decreasing MI was achieved by a higher Nmass and constant SLA (reduced LAI and constant N-pool) in high-rainfall areas (MI > 0·29), but by a lower SLA and Nmass (reduced LAI and N-pool) in low-rainfall areas (MI ≤ 0·29). While δ(13)C, CCmass and CCarea continuously increased with decreasing MI, the low-rainfall group had higher Narea and δ(13)C at a given CCarea, compared with the high-rainfall group. Similar patterns were also found in additional data for the same species in the northern Tibetan Plateau. The observed drought threshold where MI = 0·29 corresponded well to the zonal boundary between typical and desert steppes in northern China. Our data indicated that below a climatic drought threshold, drought-resistant plants tend to maximize their intrinsic WUE through increased Narea at a given CCarea, which suggests a linkage between leaf functional traits and arid vegetation zonation. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please

Investigating contact toxicity of Geranium and Artemisia essential oils on Bemisia tabaci Gen.

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Fatemeh Yarahmadi

2013-04-01

Full Text Available Objective: Sweet potato whitefly, Bemisia tabaci Gen. (B. tabaci, is one of the most important pests of various greenhouse crops in Iran. Nowadays, chemical insecticides are broadly used for control of the pests that causes risk to consumer's health. For the first time, contact toxicity of Pelargonium roseum Andrews and Artemisia sieberi Besser essential oils on B. tabaci and its possible application against the whitefly was evaluated in 2012. Materials and Methods: Essential oil with concentrations of 2500, 1250, 125, and 12 ppm were used. Infested leaves of greenhouse cucumber were treated by mentioned concentrations. After 24 hours, mortality of B. tabaci was recorded and compared after correcting by Abbot's formula. Results: Results showed that all concentrations of the essential oil could significantly reduce population of B. tabaci compared with the control treatment. Phytotoxicity of the treated leaves were recorded after 24, 48, and 72 hours and compared with the control. Concentrations of 2500, 1250, and 125 ppm caused severe phytotoxicity on greenhouse cucumber leaves and therefore are not suitable for greenhouse application. Phytotoxicity of 12 ppm was relatively low. Conclusions: This data implicated suitable protective effects of the essential oils to the pest infestation. Therefore, essential oils distillated from Geranium and Artemisia could be applied to control B. tabaci in greenhouse cucumber at V/V 12 ppm.

RNAi down-regulation of cinnamate-4-hydroxylase increases artemisinin biosynthesis in Artemisia annua

OpenAIRE

Kumar, Ritesh; Vashisth, Divya; Misra, Amita; Akhtar, Md Qussen; Jalil, Syed Uzma; Shanker, Karuna; Gupta, Madan Mohan; Rout, Prashant Kumar; Gupta, Anil Kumar; Shasany, Ajit Kumar

2016-01-01

Cinnamate-4-hydroxylase (C4H) converts trans-cinnamic acid (CA) to p-coumaric acid (COA) in the phenylpropanoid/lignin biosynthesis pathway. Earlier we reported increased expression of AaCYP71AV1 (an important gene of artemisinin biosynthesis pathway) caused by CA treatment in Artemisia annua. Hence, AaC4H gene was identified, cloned, characterized and silenced in A. annua with the assumption that the elevated internal CA due to knock down may increase the artemisinin yield. Accumulation of t...

Antibacterial and antiprotozoal effect of Artemisia annua extracts

DEFF Research Database (Denmark)

Ivarsen, E.; Fretté, X. C.; Engberg, R. M.

2012-01-01

be banned in the EU. Extracts of aerial parts of Artemisia annua (AA) showed antimicrobial activity in overnight cultures of CP strains isolated from diseased broilers. The hexane extract (HEX) gave the strongest inhibition (MIC=185ppm) while the dichloromethane extract (DCM) gave a weaker inhibition (MIC......=270ppm). The dietary incorporation of HEX reduced the population of CP and the severity of the associated small intestinal lesions (P>0.05) in broilers when applying a NE disease model. The antibacterial compounds from HEX and DCM, chrysosplenol and ponticaepoxide, were isolated. This is the first...... report of activity against CP for these compounds. HEX, DCM and artemisinin were also tested against HM. The two latter showed highest antiprotozoal effect in vitro (MLC=1.0mg/ml and IC50=1.3mg/ml respectively), and were tested in vivo in infected poultry. However, no effect against HM at the given...

Evolutionary and ecological implications of genome size in the North American endemic sagebrushes and allies (Artemisia, Asteraceae)

Science.gov (United States)

Sonia Garcia; Miguel A. Canela; Teresa Garnatje; E. Durant McArthur; Jaume Pellicer; Stewart C. Sanderson; Joan Valles

2008-01-01

The genome size of 51 populations of 20 species of the North American endemic sagebrushes (subgenus Tridentatae), related species, and some hybrid taxa were assessed by flow cytometry, and were analysed in a phylogenetic framework. Results were similar for most Tridentatae species, with the exception of three taxonomically conflictive species: Artemisia bigelovii Gray...

Final report on the safety assessment of AloeAndongensis Extract, Aloe Andongensis Leaf Juice,aloe Arborescens Leaf Extract, Aloe Arborescens Leaf Juice, Aloe Arborescens Leaf Protoplasts, Aloe Barbadensis Flower Extract, Aloe Barbadensis Leaf, Aloe Barbadensis Leaf Extract, Aloe Barbadensis Leaf Juice,aloe Barbadensis Leaf Polysaccharides, Aloe Barbadensis Leaf Water, Aloe Ferox Leaf Extract, Aloe Ferox Leaf Juice, and Aloe Ferox Leaf Juice Extract.

Science.gov (United States)

2007-01-01

Plant materials derived from the Aloe plant are used as cosmetic ingredients, including Aloe Andongensis Extract, Aloe Andongensis Leaf Juice, Aloe Arborescens Leaf Extract, Aloe Arborescens Leaf Juice, Aloe Arborescens Leaf Protoplasts, Aloe Barbadensis Flower Extract, Aloe Barbadensis Leaf, Aloe Barbadensis Leaf Extract, Aloe Barbadensis Leaf Juice, Aloe Barbadensis Leaf Polysaccharides, Aloe Barbadensis Leaf Water, Aloe Ferox Leaf Extract, Aloe Ferox Leaf Juice, and Aloe Ferox Leaf Juice Extract. These ingredients function primarily as skin-conditioning agents and are included in cosmetics only at low concentrations. The Aloe leaf consists of the pericyclic cells, found just below the plant's skin, and the inner central area of the leaf, i.e., the gel, which is used for cosmetic products. The pericyclic cells produce a bitter, yellow latex containing a number of anthraquinones, phototoxic compounds that are also gastrointestinal irritants responsible for cathartic effects. The gel contains polysaccharides, which can be acetylated, partially acetylated, or not acetylated. An industry established limit for anthraquinones in aloe-derived material for nonmedicinal use is 50 ppm or lower. Aloe-derived ingredients are used in a wide variety of cosmetic product types at concentrations of raw material that are 0.1% or less, although can be as high as 20%. The concentration of Aloe in the raw material also may vary from 100% to a low of 0.0005%. Oral administration of various anthraquinone components results in a rise in their blood concentrations, wide systemic distribution, accumulation in the liver and kidneys, and excretion in urine and feces; polysaccharide components are distributed systemically and metabolized into smaller molecules. aloe-derived material has fungicidal, antimicrobial, and antiviral activities, and has been effective in wound healing and infection treatment in animals. Aloe barbadensis (also known as Aloe vera)-derived ingredients were not toxic

Chemical composition and acetylcholinesterase inhibitory activity of Artemisia maderaspatana essential oil.

Science.gov (United States)

Jyotshna; Srivastava, Nidhi; Singh, Bhuwanendra; Chanda, Debabrata; Shanker, Karuna

2015-01-01

To date, there are no reports to validate the Indian traditional and folklore claims of Artemisia maderaspatana L. (syn. Grangea maderaspatana L.) (Asteraceae) for the treatment of Alzheimer's disease. The present study characterizes the volatile components (non-polar compounds) of A. maderaspatana and evaluates its acetylcholinesterase inhibition potential. The essential oils (yield 0.06% v/w) were obtained from fresh aerial part of A. maderaspatana. The characterization of volatile components (non-polar compounds) was performed by GC-MS data and with those of reference compounds compiled in the spectral library of in-house database. The in vitro acetylcholinesterase (AChE) inhibition of the volatile organic constituents (VOC's) of A. maderaspatana aerial part was evaluated in varying concentration ranges (0.70-44.75 µg/mL) with Ellman's method. The major components were α-humulene (46.3%), β-caryophyllene (9.3%), α-copaene (8.2%), β-myrcene (4.3%), Z(E)-α-farnesene (3.7%), and calarene (3.5%). Chemical variability among other Artemisia spp. from different climatic regions of India and countries namely Iran and France was observed. The experimental results showed that diverse volatile organic constituents of A. maderaspatana have significant acetylcholinesterase inhibitory activity (an IC50 value of 31.33 ± 1.03 µg/mL). This is the first report on the inhibition of acetylcholinesterase properties of essential oil of A. maderaspatana obtained from fresh aerial part. The present results indicate that essential oil of A. maderaspatana isolated from the northern region of India could inhibit AChE moderately. Therefore, the possibility of novel AChE inhibitors might exist in VOCs of this plant.

Identification of Repellent and Insecticidal Constituents from Artemisia mongolica Essential Oil against Lasioderma serricorne

OpenAIRE

You, Chunxue; Guo, Shanshan; Zhang, Wenjuan; Yang, Kai; Geng, Zhufeng; Du, Shushan; Wang, Chengfang; Deng, Zhiwei

2015-01-01

The aims of this research were to determine the chemical composition and insecticidal and repellent activities of the Artemisia mongolica essential oil against Lasioderma serricorne and to isolate active constituents from the essential oil. The essential oil of A. mongolica was obtained by hydrodistillation and 36 components were identified with GC-MS. Eucalyptol (39.88%), (S)-cis-verbenol (14.93%), 4-terpineol (7.20%), (−)-camphor (6.02%), and α-terpineol (4.20%) were found to be major compo...

Ribosomal DNA, heterochromatin, and correlation with genome size in diploid and polyploid North American endemic sagebrushes (Artemisia, Asteraceae)

Science.gov (United States)

Sonia Garcia; Teresa Garnatje; Jaume Pellicer; E. Durant McArthur; Sonja Siljak-Yakovlev; Joan Valles

2009-01-01

Subgenus Tridentatae (Artemisia, Asteraceae) can be considered a polyploid complex. Both polyploidy and hybridization have been documented in the Tridentatae. Fluorescent in situ hybridization (FISH) and fluorochrome banding were used to detect and analyze ribosomal DNA changes linked to polyploidization in this group by studying four diploidpolyploid species pairs. In...

Exogenous nitric oxide donor protects Artemisia annua from oxidative stress generated by boron and aluminium toxicity.

Science.gov (United States)

Aftab, Tariq; Khan, M Masroor A; Naeem, M; Idrees, Mohd; Moinuddin; Teixeira da Silva, Jaime A; Ram, M

2012-06-01

Nitric oxide (NO) is an important signal molecule modulating the response of plants to environmental stress. Here we report the effects of boron (B) and aluminium (Al) contamination in soil, carried out with or without application of exogenous SNP (NO donor), on various plant processes in Artemisia annua, including changes in artemisinin content. The addition of B or Al to soil medium significantly reduced the yield and growth of plants and lowered the values of net photosynthetic rate, stomatal conductance, internal CO(2) concentration and total chlorophyll content. The follow-up treatment of NO donor favoured growth and improved the photosynthetic efficiency in stressed as well as non-stressed plants. Artemisinin content was enhanced by 24.6% and 43.8% at 1mmole of soil-applied B or Al. When SNP was applied at 2mmole concentration together with either 1mmole of B and/or Al, it further stimulated artemisinin biosynthesis compared to the control. Application of B+Al+SNP proved to be the best treatment combination for the artemisinin content in Artemisia annua leaves. Copyright © 2012 Elsevier Inc. All rights reserved.

Maize YABBY genes drooping leaf1 and drooping leaf2 affect agronomic traits by regulating leaf architecture

Science.gov (United States)

Leaf architectural traits, such as length, width and angle, directly influence canopy structure and light penetration, photosynthate production and overall yield. We discovered and characterized a maize (Zea mays) mutant with aberrant leaf architecture we named drooping leaf1 (drl1), as leaf blades ...

Chemical composition of the essentialoil of the artemisia arborescens L. growing wild in Lebanon

International Nuclear Information System (INIS)

El Beyrouthy, M.; Arnold-Spotolides, N.; Labaki, M.; Najm, S.; Cazier, F.; Abou kais, A.

2011-01-01

The essential oil obtained by hydrodistillation from air dried aerial parts of Artemisia arborescens L. from Lebanon was analyzed by GC/MS. Forty three compounds representing 95.33% of the oil sample were identified. The major component wasβ -thujone (68.5%), followed by chamazulene (12.3%), and some lesser amounts of terpinen-4-ol (1.8%), myrcene (1.3%),α -thujone (1.2%), linalool (1%), cis-thuyanol-4-ol (1%), carvacrol (0.9%), β -cubebene (0.8%) and camphor (0.8%).

Deep sequencing of amplicons reveals widespread intraspecific hybridization and multiple origins of polyploidy in big sagebrush (Artemisia tridentata, Asteraceae)

Science.gov (United States)

Bryce A. Richardson; Justin T. Page; Prabin Bajgain; Stewart C. Sanderson; Joshua A. Udall

2012-01-01

Premise of the study: Hybridization has played an important role in the evolution and ecological adaptation of diploid and polyploid plants. Artemisia tridentata (Asteraceae) tetraploids are extremely widespread and of great ecological importance. These tetraploids are often taxonomically identified as A. tridentata subsp. wyomingensis or as autotetraploids of diploid...

Production of artemisinin and its derivatives in hairy roots of Artemisia dubia induced by rolA gene transformation

International Nuclear Information System (INIS)

Amanullah, M.; Mirza, B.; Zia, M.

2016-01-01

Artemisinin and its derivatives are phytochemical constituents of genus Artemisia. Demand of these plant secondary metabolitesis increasing due to their immense therapeutic significance. Besides their established antimalarial role, recent studies have also disclosed their anticancer potentials. It has made imperative to develop new and efficient sources of these compounds. Inherent synthetic challenges give biological sources preference over chemical synthesis of artemisinin and its derivatives. Therefore, genetic improvement of plants and, rather less preferentially, microbes is focus of current research to gain increase productivity of these valuable drugs. This study has analyzed A. dubiaas potential source of artemisinin and its derivatives. Transformation of Artemisia dubia was carried out using A. tumefaciens strain LBA 4404 containing rolA gene constructed on pRB 29. Healthy and acclimatizable transgenic plants were produced using optimized concentrations of BAP and NAA. Previously acclimatized rol ABC transgenic plants were also In vitro regenerated for comparative analysis of artemisinin and its derivatives. PCR amplification of rolA gene was done to confirm the integration of T-DNA in transgenic plants.TLC analysis was performed to evaluate comparative production of artemisinin and derivatives in rolA and rol ABC transgenic A. dubia. It revealed that rolA transgenic plants contain comparable amounts of these metabolites. Both type of transgenic plants manifested the enhancement of other uncharacterized compounds as well. Besides systematic optimization of In vitro regenerative protocol for Artemisia dubia, relative regeneration ability of rol transgenic and controlplants was also assessed at four regenerative stages. It was observed that unlike control, rol transgenic plants showed best root induction only on combination of auxins and cytokines. It was concluded that rol genes transformation of plants is an efficient tool to enhance their secondary

Composition and antimicrobial activity of essential oils of Artemisia judaica, A. herba-alba and A. arborescens from Libya

Directory of Open Access Journals (Sweden)

Janaćković Peđa

2015-01-01

Full Text Available The essential oils obtained by hydrodistillation from the aerial parts of Artemisia judaica L., Artemisia herba-alba Asso. and Artemisia arborescens L. (cultivated from Libya, were analyzed by GC and GC-MS. The antimicrobial properties were determined using the broth microdilution method against eight bacterial species: Bacillus cereus (clinical isolate, Micrococcus flavus (ATCC10240, Listeria monocytogenes (NCTC7973, Staphylococcus aureus (ATCC6538, Escherichia coli (ATCC35210, Pseudomonas aeruginosa (ATCC27853, Salmonella typhimurium (ATCC13311, Enterobacter cloacae (human isolates and eight fungal species: Aspergillus niger (ATCC6275, A. ochraceus (ATCC12066, A. versicolor (ATCC11730, A. fumigatus (ATCC1022, Penicillium ochrochloron (ATCC9112, P. funiculosum (ATCC10509, Trichoderma viride (IAM5061 and Candida albicans (human isolate. The major constituents of A. arborescens oil were sesquiterpene hydrocarbons (47.4%. Oxygenated monoterpenes were the dominant constituents in the A. judaica and A. herba-alba oils (54.2% and 77.3%, respectively. Camphor (24.7% and chamazulene (20.9% were the major components in the essential oil of A. arborescens, chrysanthenone (20.8%, cis-chrysanthenyl acetate (17.6% and cis-thujone (13.6% dominated in the A. herba-alba oil, and the major constituents in the A. judaica oil were piperitone (30.21% and cis-chrysanthenol (9.1%. The best antimicrobial activity was obtained for A. judaica oil and the lowest effect was noticed in A. arborescens oil. The effect of the tested oils was higher against Gram (+ than Gram (- bacteria. All three oils showed the best antibacterial activity against Listeria monocytogenes and the lowest against Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, compared to streptomycin and ampicillin. All three oils showed better antifungal activities than ketoconazole, except A. arborescens oil against Aspergillus niger. [Projekat Ministarstv nauke Republike Srbije, br. 173029

Hypolipidaemic Effect of Hericium erinaceum Grown in Artemisia capillaris on Obese Rats.

Science.gov (United States)

Choi, Won-Sik; Kim, Young-Sun; Park, Byeoung-Soo; Kim, Jang-Eok; Lee, Sung-Eun

2013-06-01

In this study, ethanolic extracts from Hericium erinaceum cultivated with Artemisia capillaris (HEAC) were assessed for their ability to lower the cholesterol levels of male Sprague-Dawley rats fed a high-fat diet. Rats were randomly subdivided into seven test groups. Each group contained eight rats fed a high-fat diet during a growth period lasting 4 wk. Supplementation with the extracts was performed once a day for 2 wk after the high-fat diet. The control group (rats fed a high-fat diet) showed a high efficiency ratio (feed efficiency ratio) value compared to the normal group. Biochemical parameters, including total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and triglyceride (TG) levels dramatically increased in the control group compared to the normal group. High-density lipoprotein-cholesterol (HDL-c) content in the control group was also significantly lower relative to the normal group. Two positive control groups, treated with simvastatin and atorvastatin, had lowered TC, LDL-c, and TG levels, and increased HDL-c content compared to the control group. Treatment with the tested extracts, including HEAC, ethanolic extracts from Hericium erinaceum, and ethanolic extracts from Artemisia capillaris reduced TC, LDL-c, and TG levels and elevated HDL-c content in the hyperlipidemia rats. The atherogenic index and cardiac risk factor values for the HEAC-treated group were 0.95 and 1.95, respectively. Simvastatin- and atorvastatin-treated groups showed atherogenic index values of 1.56 and 1.69, respectively, and cardiac risk factor values of 2.56 and 2.69, respectively. These results show HEAC possesses an ability to cure hyperlipidemia in rats and may serve as an effective natural medicine for treating hyperlipidemia in humans.

Composition of the Essential oil of Artemisia absinthium from Tajikistan

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Farukh S. Sharopov

2012-01-01

Full Text Available Three samples of Artemisia absinthium were collected from two different locations in the central-south of Tajikistan. The essential oils were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. A total of 41 compounds were identified representing 72-94% of total oil compositions. The major components of A. absinthium oil were myrcene (8.6-22.7%, cis-chrysanthenyl acetate (7.7-17.9%, a dihydrochamazulene isomer (5.5-11.6%, germacrene D (2.4-8.0%, β-thujone (0.4-7.3%, linalool acetate (trace-7.0%, α-phellandrene (1.0-5.3%, and linalool (5.3-7.0%. The chemical compositions of A. absinthium from Tajikistan are markedly different from those from European, Middle Eastern, or other Asian locations and likely represent new chemotypes.

Antioxidant activities and essential oil composition of Herba Artemisiae Scopariae from China.

Science.gov (United States)

Jiang, Shan; Lai, Pengxiang; Li, Jie; Wang, Guichun

2012-01-01

The essential oil in traditional Chinese medicine (TCM) Herba Artemisiae Scopariae (HAC) grown in China was obtained by hydrodistillation and studied by GC and GC-MS. Twenty compounds were identified representing 96.6% of the essential oil, of which the most prominent were n-hexadecanoic acid (33.1%), caryophyllene oxide (19.1%) and spathulenol (9.9%). The antioxidant activity of the essential oil (25-400 µg/ml) of HAC was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/antioxidant power (FRAP) assay. The essential oil of HAC exhibited a strong antioxidant activity, which possess a good potential for use in the food and pharmaceutical industry.

Flavonoids from Artemisia annua L. as Antioxidants and Their Potential Synergism with Artemisinin against Malaria and Cancer

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Jorge F.S. Ferreira

2010-04-01

Full Text Available Artemisia annua is currently the only commercial source of the sesquiterpene lactone artemisinin.Since artemisinin was discovered as the active component of A. annua in early 1970s, hundreds of papers have focused on the anti-parasitic effects of artemisinin and its semi-synthetic analogs dihydroartemisinin, artemether, arteether, and artesunate. Artemisinin per se has not been used in mainstream clinical practice due to its poor bioavailability when compared to its analogs. In the past decade, the work with artemisinin-based compounds has expanded to their anti-cancer properties. Although artemisinin is a major bioactive component present in the traditional Chinese herbal preparations (tea, leaf flavonoids, also present in the tea, have shown a variety of biological activities and may synergize the effects of artemisinin against malaria and cancer. However, only a few studies have focused on the potential synergistic effects between flavonoids and artemisinin. The resurgent idea that multi-component drug therapy might be better than monotherapy is illustrated by the recent resolution of the World Health Organization to support artemisinin-based combination therapies (ACT, instead of the previously used monotherapy with artemisinins. In this critical review we will discuss the possibility that artemisinin and its semi-synthetic analogs might become more effective to treat parasitic diseases (such as malaria and cancer if simultaneously delivered with flavonoids. The flavonoids present in A. annua leaves have been linked to suppression of CYP450 enzymes responsible for altering the absorption and metabolism of artemisinin in the body, but also have been linked to a beneficial immunomodulatory activity in subjects afflicted with parasitic and chronic diseases.

High-fat diet-induced neuropathy of prediabetes and obesity: effect of PMI-5011, an ethanolic extract of Artemisia dracunculus L.

Science.gov (United States)

Watcho, Pierre; Stavniichuk, Roman; Ribnicky, David M; Raskin, Ilya; Obrosova, Irina G

2010-01-01

Artemisia species are a rich source of herbal remedies with antioxidant and anti-inflammatory properties. We evaluated PMI-5011, an ethanolic extract of Artemisia dracunculus L., on neuropathy in high-fat diet-fed mice, a model of prediabetes and obesity developing oxidative stress and proinflammatory changes in peripheral nervous system. C57Bl6/J mice fed high-fat diet for 16 weeks developed obesity, moderate nonfasting hyperglycemia, nerve conduction deficit, thermal and mechanical hypoalgesia, and tactile allodynia. They displayed 12/15-lipoxygenase overexpression, 12(S)-hydroxyeicosatetraenoic acid accumulation, and nitrosative stress in peripheral nerve and spinal cord. PMI-5011 (500 mg kg(-1) d(-1), 7 weeks) normalized glycemia, alleviated nerve conduction slowing and sensory neuropathy, and reduced 12/15-lipoxygenase upregulation and nitrated protein expression in peripheral nervous system. PMI-5011, a safe and nontoxic botanical extract, may find use in treatment of neuropathic changes at the earliest stage of disease.

Phylogeny of Artemisia L.: Recent developments

African Journals Online (AJOL)

STORAGESEVER

2009-06-03

Jun 3, 2009 ... 1Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan. 2National ... It is a well known wind pollinated cosmopolitan genus ... (ITS) of nuclear ribosomal DNA (Kornkven et al., 1998; ..... The leaf structure.

"Breath figures" on leaf surfaces-formation and effects of microscopic leaf wetness.

Science.gov (United States)

Burkhardt, Juergen; Hunsche, Mauricio

2013-01-01

"Microscopic leaf wetness" means minute amounts of persistent liquid water on leaf surfaces which are invisible to the naked eye. The water is mainly maintained by transpired water vapor condensing onto the leaf surface and to attached leaf surface particles. With an estimated average thickness of less than 1 μm, microscopic leaf wetness is about two orders of magnitude thinner than morning dewfall. The most important physical processes which reduce the saturation vapor pressure and promote condensation are cuticular absorption and the deliquescence of hygroscopic leaf surface particles. Deliquescent salts form highly concentrated solutions. Depending on the type and concentration of the dissolved ions, the physicochemical properties of microscopic leaf wetness can be considerably different from those of pure water. Microscopic leaf wetness can form continuous thin layers on hydrophobic leaf surfaces and in specific cases can act similar to surfactants, enabling a strong potential influence on the foliar exchange of ions. Microscopic leaf wetness can also enhance the dissolution, the emission, and the reaction of specific atmospheric trace gases e.g., ammonia, SO2, or ozone, leading to a strong potential role for microscopic leaf wetness in plant/atmosphere interaction. Due to its difficult detection, there is little knowledge about the occurrence and the properties of microscopic leaf wetness. However, based on the existing evidence and on physicochemical reasoning it can be hypothesized that microscopic leaf wetness occurs on almost any plant worldwide and often permanently, and that it significantly influences the exchange processes of the leaf surface with its neighboring compartments, i.e., the plant interior and the atmosphere. The omission of microscopic water in general leaf wetness concepts has caused far-reaching, misleading conclusions in the past.

The presence of eucalyptol in Artemisia australis validates its use in traditional Hawaiian medicine

Institute of Scientific and Technical Information of China (English)

David; Zant; Daniel; A.Gubler

2014-01-01

Objective:To identify the major organic compounds of Artemisia austeralis(A.australis),a plant used in traditional Hawaiian medicine for the treatment of asthma.Methods:The dichloromethane extract of A.australis was analyzed by gas chromatography—mass spectroscopy and major compounds were identified by a National Institute of Standards and Technology library search and confirmed by peak enhancement Results:The major chemical components of A.australis include eucalyptol.borneol,and caryophyllene.Conclusions:The presence and biological activity of eucalyptol correlate very well with the usage of this plant in traditional Hawaiian medicine.

The presence of eucalyptol in Artemisia australis validates its use in traditional Hawaiian medicine

Institute of Scientific and Technical Information of China (English)

David Zant; Daniel A. Gubler

2014-01-01

Objective: To identify the major organic compounds of Artemisia australis (A. australis), a plant used in traditional Hawaiian medicine for the treatment of asthma.Methods:The dichloromethane extract of A. australis was analyzed by gas chromatography-mass spectroscopy and major compounds were identified by a National Institute of Standards and Technology library search and confirmed by peak enhancement.Results:The major chemical components of A. australis include eucalyptol, borneol, and caryophyllene.Conclusions:The presence and biological activity of eucalyptol correlate very well with the usage of this plant in traditional Hawaiian medicine.

Effect of Plant Growth Regulators on Leaf Number, Leaf Area and Leaf Dry Matter in Grape

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Zahoor Ahmad BHAT

2011-03-01

Full Text Available Influence of phenylureas (CPPU and brassinosteriod (BR along with GA (gibberellic acid were studied on seedless grape vegetative characteristics like leaf number, leaf area and leaf dry matter. Growth regulators were sprayed on the vines either once (7 days after fruit set or 15 days after fruit set or twice (7+15 days after fruit set. CPPU 2 ppm+BR 0.4 ppm+GA 25 ppm produced maximum number of leaves (18.78 while as untreated vines produced least leaf number (16.22 per shoot. Maximum leaf area (129.70 cm2 and dry matter content (26.51% was obtained with higher CPPU (3 ppm and BR (0.4 ppm combination along with GA 25 ppm. Plant growth regulators whether naturally derived or synthetic are used to improve the productivity and quality of grapes. The relatively high value of grapes justifies more expensive inputs. A relatively small improvement in yield or fruit quality can justify the field application of a very costly product. Application of new generation growth regulators like brassinosteroids and phenylureas like CPPU have been reported to increase the leaf number as well as leaf area and dry matter thereby indirectly influencing the fruit yield and quality in grapes.

Green synthesis and characterization of silver nanoparticles using Artemisia absinthium aqueous extract — A comprehensive study

International Nuclear Information System (INIS)

Ali, Mohammad; Kim, Bosung; Belfield, Kevin D.; Norman, David; Brennan, Mary; Ali, Gul Shad

2016-01-01

Unlike chemical synthesis, biological synthesis of nanoparticles is gaining tremendous interest, and plant extracts are preferred over other biological sources due to their ample availability and wide array of reducing metabolites. In this project, we investigated the reducing potential of aqueous extract of Artemisia absinthium L. for synthesizing silver nanoparticles (AgNPs). Optimal synthesis of AgNPs with desirable physical and biological properties was investigated using ultra violet–visible spectroscopy (UV–vis), dynamic light scattering (DLS), transmission electron microscopy (TEM) and energy-dispersive X-ray analysis (EDX). To determine their appropriate concentrations for AgNP synthesis, two-fold dilutions of silver nitrate (20 to 0.62 mM) and aqueous plant extract (100 to 0.79 mg ml"−"1) were reacted. The results showed that silver nitrate (2 mM) and plant extract (10 mg ml"−"1) mixed in different ratios significantly affected size, stability and yield of AgNPs. Extract to AgNO_3 ratio of 6:4 v/v resulted in the highest conversion efficiency of AgNO_3 to AgNPs, with the particles in average size range of less than 100 nm. Furthermore, the direct imaging of synthesized AgNPs by TEM revealed polydispersed particles in the size range of 5 to 20 nm. Similarly, nanoparticles with the characteristic peak of silver were observed with EDX. This study presents a comprehensive investigation of the differential behavior of plant extract and AgNO_3 to synthesize biologically stable AgNPs. - Graphical abstract: Aqueous extract from Artemisia absinthium when used in appropriate ratio (shown in Eppendorf tubes and microtiter plate) is highly active in reducing elemental silver to colloidal silver nanoparticles in the 5–20 nm size range (shown in TEM image, bottom left panel; DLS histogram, upper left panel; EDX analysis, bottom right panel). - Highlights: • Artemisia absinthium extract provides excellent reducing potential for biosynthesis of silver

Green synthesis and characterization of silver nanoparticles using Artemisia absinthium aqueous extract — A comprehensive study

Energy Technology Data Exchange (ETDEWEB)

Ali, Mohammad [Mid-Florida Research and Education Center and Department of Plant Pathology, University of Florida/Institute of Food and Agricultural Sciences, 2725 Binion Rd., Apopka, FL 32703 (United States); Kim, Bosung [Department of Chemistry, University of Central Florida, Orlando, FL 32816 (United States); Belfield, Kevin D. [Department of Chemistry, University of Central Florida, Orlando, FL 32816 (United States); College of Science and Liberal Arts, New Jersey Institute of Technology, Newark, NJ 07102 (United States); Norman, David; Brennan, Mary [Mid-Florida Research and Education Center and Department of Plant Pathology, University of Florida/Institute of Food and Agricultural Sciences, 2725 Binion Rd., Apopka, FL 32703 (United States); Ali, Gul Shad, E-mail: gsali@ufl.edu [Mid-Florida Research and Education Center and Department of Plant Pathology, University of Florida/Institute of Food and Agricultural Sciences, 2725 Binion Rd., Apopka, FL 32703 (United States)

2016-01-01

Unlike chemical synthesis, biological synthesis of nanoparticles is gaining tremendous interest, and plant extracts are preferred over other biological sources due to their ample availability and wide array of reducing metabolites. In this project, we investigated the reducing potential of aqueous extract of Artemisia absinthium L. for synthesizing silver nanoparticles (AgNPs). Optimal synthesis of AgNPs with desirable physical and biological properties was investigated using ultra violet–visible spectroscopy (UV–vis), dynamic light scattering (DLS), transmission electron microscopy (TEM) and energy-dispersive X-ray analysis (EDX). To determine their appropriate concentrations for AgNP synthesis, two-fold dilutions of silver nitrate (20 to 0.62 mM) and aqueous plant extract (100 to 0.79 mg ml{sup −1}) were reacted. The results showed that silver nitrate (2 mM) and plant extract (10 mg ml{sup −1}) mixed in different ratios significantly affected size, stability and yield of AgNPs. Extract to AgNO{sub 3} ratio of 6:4 v/v resulted in the highest conversion efficiency of AgNO{sub 3} to AgNPs, with the particles in average size range of less than 100 nm. Furthermore, the direct imaging of synthesized AgNPs by TEM revealed polydispersed particles in the size range of 5 to 20 nm. Similarly, nanoparticles with the characteristic peak of silver were observed with EDX. This study presents a comprehensive investigation of the differential behavior of plant extract and AgNO{sub 3} to synthesize biologically stable AgNPs. - Graphical abstract: Aqueous extract from Artemisia absinthium when used in appropriate ratio (shown in Eppendorf tubes and microtiter plate) is highly active in reducing elemental silver to colloidal silver nanoparticles in the 5–20 nm size range (shown in TEM image, bottom left panel; DLS histogram, upper left panel; EDX analysis, bottom right panel). - Highlights: • Artemisia absinthium extract provides excellent reducing potential for

Why do leaf-tying caterpillars abandon their leaf ties?

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Michelle Sliwinski

2013-09-01

Full Text Available Leaf-tying caterpillars act as ecosystem engineers by building shelters between overlapping leaves, which are inhabited by other arthropods. Leaf-tiers have been observed to leave their ties and create new shelters (and thus additional microhabitats, but the ecological factors affecting shelter fidelity are poorly known. For this study, we explored the effects of resource limitation and occupant density on shelter fidelity and assessed the consequences of shelter abandonment. We first quantified the area of leaf material required for a caterpillar to fully develop for two of the most common leaf-tiers that feed on white oak, Quercus alba. On average, Psilocorsis spp. caterpillars consumed 21.65 ± 0.67 cm2 leaf material to complete development. We also measured the area of natural leaf ties found in a Maryland forest, to determine the distribution of resources available to caterpillars in situ. Of 158 natural leaf ties examined, 47% were too small to sustain an average Psilocorsis spp. caterpillar for the entirety of its development. We also manipulated caterpillar densities within experimental ties on potted trees to determine the effects of cohabitants on the likelihood of a caterpillar to leave its tie. We placed 1, 2, or 4 caterpillars in ties of a standard size and monitored the caterpillars twice daily to track their movement. In ties with more than one occupant, caterpillars showed a significantly greater propensity to leave their tie, and left sooner and at a faster rate than those in ties as single occupants. To understand the consequences of leaf tie abandonment, we observed caterpillars searching a tree for a site to build a shelter in the field. This is a risky behavior, as 17% of the caterpillars observed died while searching for a shelter site. Caterpillars that successfully built a shelter traveled 110 ± 20 cm and took 28 ± 7 min to find a suitable site to build a shelter. In conclusion, leaf-tying caterpillars must frequently

Artemisia spicigera Essential Oil: Assessment of Phytochemical and Antioxidant Properties

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Ghajarbeygi

2015-11-01

Full Text Available Background Essential oils (EO, also called volatile odoriferous oil, are aromatic oily liquids extracted from different parts of plants. In general, the constituents in EOs are terpenes, aromatic compounds (aldehyde, alcohol, phenol, methoxy derivatives, and so on, and terpenoids (isoprenoids. Essential Oils have been known to possess antioxidant and antimicrobial activities, thereby serving as natural additives in foods and food products. Objectives The aim of this study was to assess the quantity and quality of compounds, with active chemical and antioxidant properties, of Artemisia spicigera essential oil (EO due to the effect of geographic location and season of harvest on the phenolic compounds of the plant. The plant was collected from east Azarbayjan province, Iran (both before and after the flowering stage. Materials and Methods A. spicigera EO was analyzed by gas chromatogram/mass spectrometry (GC-MS. The antioxidant activity and total phenolic content before and after flowering were evaluated by the Folin Ciocalteu method. Also, the yields of essential oil as a percentage based on the level of dry plant and the volume of extracted oil was determined. Results Analysis of A. spicigera EO by gas chromatogram-mass spectrometry showed that spachulenol 1 H cycloprop (18.39% and bicyclo hexan-3-en, 4-met (26.16%, were the prominent EOs of Artemisia before and after the flowering stage; the total phenolic EO before and after the flowering stage was 23.61 ± 1.08 µg/mL and 17.71 ± 0.9 µg/mL, respectively. Also level of flavonoid content before and after the flowering stage was 37.27 ± 1.70 µg/mL and 29.04 ± 1.30 µg/mL, respectively. This EO was able to reduce the stable free radical 2, 2-diphenol,1-picryl hydrazyl (DPPH with an IC50 of 86.14 ± 2.23 and 96.18 ± 2.61 µg/mL, before and after flowering, respectively. Yield of EO before and after flowering was 0.5% and 0.6%, respectively. Conclusions Results have shown that A. spicigera EO

Narrow hybrid zone between two subspecies of big sagebrush (Artemisia tridentata: Asteraceae): XI. Plant-insect interactions in reciprocal transplant gardens

Science.gov (United States)

John H. Graham; E. Durant McArthur; D. Carl Freeman

2001-01-01

Basin big sagebrush (Artemisia tridentata ssp. tridentata) and mountain big sagebrush (A. t. ssp. vaseyana) hybridize in a narrow zone near Salt Creek, Utah. Reciprocal transplant experiments in this hybrid zone demonstrate that hybrids are more fit than either parental subspecies, but only in the hybrid zone. Do hybrids experience greater, or lesser, use by...

Can Leaf Spectroscopy Predict Leaf and Forest Traits Along a Peruvian Tropical Forest Elevation Gradient?

Science.gov (United States)

Doughty, Christopher E.; Santos-Andrade, P. E.; Goldsmith, G. R.; Blonder, B.; Shenkin, A.; Bentley, L. P.; Chavana-Bryant, C.; Huaraca-Huasco, W.; Díaz, S.; Salinas, N.; Enquist, B. J.; Martin, R.; Asner, G. P.; Malhi, Y.

2017-11-01

High-resolution spectroscopy can be used to measure leaf chemical and structural traits. Such leaf traits are often highly correlated to other traits, such as photosynthesis, through the leaf economics spectrum. We measured VNIR (visible-near infrared) leaf reflectance (400-1,075 nm) of sunlit and shaded leaves in 150 dominant species across ten, 1 ha plots along a 3,300 m elevation gradient in Peru (on 4,284 individual leaves). We used partial least squares (PLS) regression to compare leaf reflectance to chemical traits, such as nitrogen and phosphorus, structural traits, including leaf mass per area (LMA), branch wood density and leaf venation, and "higher-level" traits such as leaf photosynthetic capacity, leaf water repellency, and woody growth rates. Empirical models using leaf reflectance predicted leaf N and LMA (r2 > 30% and %RMSE < 30%), weakly predicted leaf venation, photosynthesis, and branch density (r2 between 10 and 35% and %RMSE between 10% and 65%), and did not predict leaf water repellency or woody growth rates (r2<5%). Prediction of higher-level traits such as photosynthesis and branch density is likely due to these traits correlations with LMA, a trait readily predicted with leaf spectroscopy.

Leaf size and leaf display of thirty-eight tropical tree species

NARCIS (Netherlands)

Poorter, L.; Rozendaal, D.M.A.

2008-01-01

Trees forage for light through optimal leaf display. Effective leaf display is determined by metamer traits (i.e., the internode, petiole, and corresponding leaf), and thus these traits strongly co-determine carbon gain and as a result competitive advantage in a light-limited environment. We

Characterization of Nutritional Composition, Antioxidative Capacity, and Sensory Attributes of Seomae Mugwort, a Native Korean Variety of Artemisia argyi H. Lév. & Vaniot

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Jae Kyeom Kim

2015-01-01

Full Text Available Few studies have investigated Seomae mugwort (a Korean native mugwort variety of Artemisia argyi H. Lév. & Vaniot, exclusively cultivated in the southern Korean peninsula, and the possibility of its use as a food resource. In the present study, we compared the nutritional and chemical properties as well as sensory attributes of Seomae mugwort and the commonly consumed species Artemisia princeps Pamp. In comparison with A. princeps, Seomae mugwort had higher contents of polyunsaturated fatty acids, total phenolic compounds, vitamin C, and essential amino acids. In addition, Seomae mugwort had better radical scavenging activity and more diverse volatile compounds than A. princeps as well as favorable sensory attributes when consumed as tea. Given that scant information is available regarding the Seomae mugwort and its biological, chemical, and sensory characteristics, the results herein may provide important characterization data for further industrial and research applications of this mugwort variety.

Comparative study of the effects of artesunate and garlic extract on ...

African Journals Online (AJOL)

Crown gall disease causes great economic losses worldwide by reducing crop yields and increases susceptibility to opportunistic pathogens. The anti-malarial Artesunate which is a derivative of artemisinin from Artemisia annua leaf and Garlic extracts known for their inhibitory and cytotoxic effects on the proliferation of ...

Evaluation of Methane from Sisal Leaf Residue and Palash Leaf Litter

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Arisutha, S.; Baredar, P.; Deshpande, D. M.; Suresh, S.

2014-12-01

The aim of this study is to evaluate methane production from sisal leaf residue and palash leaf litter mixed with different bulky materials such as vegetable market waste, hostel kitchen waste and digested biogas slurry in a laboratory scale anaerobic reactor. The mixture was prepared with 1:1 proportion. Maximum methane content of 320 ml/day was observed in the case of sisal leaf residue mixed with vegetable market waste as the feed. Methane content was minimum (47 ml/day), when palash leaf litter was used as feed. This was due to the increased content of lignin and polyphenol in the feedstock which were of complex structure and did not get degraded directly by microorganisms. Sisal leaf residue mixtures also showed highest content of volatile fatty acids (VFAs) as compared to palash leaf litter mixtures. It was observed that VFA concentration in the digester first increased, reached maximum (when pH was minimum) and then decreased.

‘Breath figures’ on leaf surfaces – formation and effects of microscopic leaf wetness

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Jürgen eBurkhardt

2013-10-01

Full Text Available ‘Microscopic leaf wetness’ means minute amounts of persistent liquid water on leaf surfaces which are invisible to the naked eye. The water is mainly maintained by transpired water vapor condensing onto the leaf surface and to attached leaf surface particles. With an estimated average thickness of less than 1 µm, microscopic leaf wetness it is about 2 orders of magnitude thinner than morning dewfall. The most important physical processes which reduce the saturation vapor pressure and promote condensation are cuticular absorption and the deliquescence of hygroscopic leaf surface particles. Deliquescent salts form highly concentrated solutions. Depending on the amount and concentration of the dissolved ions, the physicochemical properties of microscopic leaf wetness can be considerably different from those of pure water. Microscopic leaf wetness can form continuous thin layers on hydrophobic leaf surfaces and in specific cases can act similar to surfactants, enabling a strong potential influence on the foliar exchange of ions. Microscopic leaf wetness can also enhance the dissolution, the emission, and the reaction of specific atmospheric trace gases e.g. ammonia, SO2, or ozone, leading to a strong potential role for microscopic leaf wetness in plant/atmosphere interaction. Due to its difficult detection, there is little knowledge about the occurrence and the properties of microscopic leaf wetness. However, based on the existing evidence and on physicochemical reasoning it can be hypothesized that microscopic leaf wetness occurs on almost any plant worldwide and often permanently, and that it significantly influences the exchange processes of the leaf surface with its neighboring compartments, i.e., the plant interior and the atmosphere. The omission of microscopic water in general leaf wetness concepts has caused far-reaching, misleading conclusions in the past.

Bioactivity of essential oil from Artemisia stolonifera (Maxim.) Komar. and its main compounds against two stored-product insects.

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Zhang, Wen-Juan; Yang, Kai; You, Chun-Xue; Wang, Ying; Wang, Cheng-Fang; Wu, Yan; Geng, Zhu-Feng; Su, Yang; Du, Shu-Shan; Deng, Zhi-Wei

2015-01-01

Artemisia stolonifera, a perennial herb, is widely distrbuted in China. The aim of this study was to analyze the essential oil from the aerial parts of Artemisia stolonifera, as well as to evaluate the bioactivity of the oil and its main constituents. The essential oil was analyzed by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry that allowed characterizing 22 compounds. The main components were eucalyptol (32.93%), β-pinene (8.18%), camphor (6.12%) and terpinen-4-ol (6.11%), and obtained from the essential oil after a further isolation. During the contact toxicity tests, the essential oil (LD50 = 8.60 μg/adult) exhibited stronger toxicity against Tribolium castaneum adults than those isolated constituents, however, camphor and terpinen-4-ol showed 1 and 2 times toxicity against Lasioderma serricorne adults than the essential oil (LD50 = 12.68 μg/adult) with LD50 values of 11.30 and 5.42 μg/adult, respectively. In the fumigant toxicity tests, especially on Tribolium castaneum, the essential oil (LC50 = 1.86 mg/L air) showed almost the same level toxicity as positive control, methyl bromide (LC50 = 1.75 mg/L air). Moreover, the essential oil and its four isolated constituents also exhibited strong repellency against two stored-product insects.

Arthropod repellency, especially tick (Ixodes ricinus), exerted by extract from Artemisia abrotanum and essential oil from flowers of Dianthus caryophyllum.

Science.gov (United States)

Tunón, H; Thorsell, W; Mikiver, A; Malander, I

2006-06-01

A toluene extract of southernwood (Artemisia abrotanum) and the essential oil from flowers of carnation (Dianthus caryophyllum ) exerted pronounced a repellent effect both against ticks (nymphs of Ixodes ricinus) and yellow fever mosquitoes (Aedes aegypti). The most potent repellents found were coumarin and thujyl alcohol from A. abrotanum and phenylethanol from D. caryophyllum where coumarin and thujyl alcohol were also detected.

The effects of combining Artemisia annua and Curcuma longa ethanolic extracts in broilers challenged with infective oocysts of Eimeria acervulina and E. maxima

Science.gov (United States)

Due to an increasing demand for natural products to control coccidiosis in broilers we investigated the effects of supplementing a combination of ethanolic extracts of Artemisia annua and Curcuma longa in drinking water. Three different dosages of this herbal mixture were compared with a negative co...

Type specimens of taxa of Artemisia L. (Asteraceae from Siberia and the Far East kept in the Herbarium of V.L. Komarov Botanical Insitute

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A. A. Korobkov

2015-04-01

Full Text Available Typification of 97 Artemisia (Asteraceae taxa from Siberia and the Far East kept in the Herbarium of V.L. Komarov Botanical Institute was carried out. Holotypes for 39 taxa, lectotypes for 48 taxa, 28 syntypes and 4 isotypes are given.

Leaf habit and woodiness regulate different leaf economy traits at a given nutrient supply.

Science.gov (United States)

Ordoñez, Jenny C; van Bodegom, Peter M; Witte, Jan-Philip M; Bartholomeus, Ruud P; van Dobben, Han F; Aerts, Rien

2010-11-01

The large variation in the relationships between environmental factors and plant traits observed in natural communities exemplifies the alternative solutions that plants have developed in response to the same environmental limitations. Qualitative attributes, such as growth form, woodiness, and leaf habit can be used to approximate these alternative solutions. Here, we quantified the extent to which these attributes affect leaf trait values at a given resource supply level, using measured plant traits from 105 different species (254 observations) distributed across 50 sites in mesic to wet plant communities in The Netherlands. For each site, soil total N, soil total P, and water supply estimates were obtained by field measurements and modeling. Effects of growth forms, woodiness, and leaf habit on relations between leaf traits (SLA, specific leaf area; LNC, leaf nitrogen concentration; and LPC, leaf phosphorus concentration) vs. nutrient and water supply were quantified using maximum-likelihood methods and Bonferroni post hoc tests. The qualitative attributes explained 8-23% of the variance within sites in leaf traits vs. soil fertility relationships, and therefore they can potentially be used to make better predictions of global patterns of leaf traits in relation to nutrient supply. However, at a given soil fertility, the strength of the effect of each qualitative attribute was not the same for all leaf traits. These differences may imply a differential regulation of the leaf economy traits at a given nutrient supply, in which SLA and LPC seem to be regulated in accordance to changes in plant size and architecture while LNC seems to be primarily regulated at the leaf level by factors related to leaf longevity.

Genetic Transformation of Artemisia carvifolia Buch with rol Genes Enhances Artemisinin Accumulation.

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Erum Dilshad

Full Text Available The potent antimalarial drug artemisinin has a high cost, since its only viable source to date is Artemisia annua (0.01-0.8% DW. There is therefore an urgent need to design new strategies to increase its production or to find alternative sources. In the current study, Artemisia carvifolia Buch was selected with the aim of detecting artemisinin and then enhancing the production of the target compound and its derivatives. These metabolites were determined by LC-MS in the shoots of A. carvifolia wild type plants at the following concentrations: artemisinin (8μg/g, artesunate (2.24μg/g, dihydroartemisinin (13.6μg/g and artemether (12.8μg/g. Genetic transformation of A. carvifolia was carried out with Agrobacterium tumefaciens GV3101 harboring the rol B and rol C genes. Artemisinin content increased 3-7-fold in transgenics bearing the rol B gene, and 2.3-6-fold in those with the rol C gene. A similar pattern was observed for artemisinin analogues. The dynamics of artemisinin content in transgenics and wild type A.carvifolia was also correlated with the expression of genes involved in its biosynthesis. Real time qPCR analysis revealed the differential expression of genes involved in artemisinin biosynthesis, i.e. those encoding amorpha-4, 11 diene synthase (ADS, cytochrome P450 (CYP71AV1, and aldehyde dehydrogenase 1 (ALDH1, with a relatively higher transcript level found in transgenics than in the wild type plant. Also, the gene related to trichome development and sesquiterpenoid biosynthesis (TFAR1 showed an altered expression in the transgenics compared to wild type A.carvifolia, which was in accordance with the trichome density of the respective plants. The trichome index was significantly higher in the rol B and rol C gene-expressing transgenics with an increased production of artemisinin, thereby demonstrating that the rol genes are effective inducers of plant secondary metabolism.

The Allelopathic Effects of Sinapis alba L., Achillea millefolium L.,

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R Jafarpoor

2012-02-01

Full Text Available In the recent years application of allelopathic effects in weeds managment have attracted the attention of many researchers. To study the effects of water extracts and various amount of plants powder of Sinapis, achillea, salvia, artemisia and wanut leaf on seed germination and seedling growth of bean, two separate factorial experiments were carried out in completely randomized design, with 3 and 5 replications, under laboratory and greenhouse conditions in the Agricultural Research Center Western Azerbayjan. In the first experiment, five concentrations of weeds water extracts including 0 (control, 2.5, 5, 7.5 and 10 percents was applied on bean seeds. With increasing in concentration of Sinapis, Achillea and Salvia germination percentage of bean was decreased but Artemisia and Salvia hadn’t any effects on the germination. The most preventing effect on radicle and plumule lengths of bean were observed respectively in 90.5 and 83.2 percents with 10% Sinapis concentration. In second experiment soil of the pots was extended with plants powder in rates of 0, 0.33, 0.67, 1 and 1.33 percent. Decrease in plant height and leaf area were in Salvia, with 35.6% and 57.1%, respectively. Salvia concentration of 40 gr in soil, decreased total dry matter with 54% control, but Walnut leaf with amounts of 10, 20, 30 gr in soil increased than total dry matter. Existence of more than 30 gr Salvia and 40 gr Artemisia in the soil decreased 33.7% root dry weight compared to control. 40gr Salvia in soil decreased the dry weight of the seed from 452.6mg (control to 257.6mg.

Effect of Addition of Moringa Leaf By-Product (Leaf-Waste) on ...

African Journals Online (AJOL)

The effects of incorporation of Moringa leaf fibre (a by-product of leaf processing which contains 24% Crude Fibre by dry weight at 0, 5 and 10 % substitution of wheat flour in cookies was investigated. Three products containing wheat flour: Moringa leaf fibre ratios of 100:0, 95:5, and 90:10 respectively were prepared, and a ...

Global variability in leaf respiration in relation to climate and leaf traits

Science.gov (United States)

Atkin, Owen K.

2015-04-01

Leaf respiration plays a vital role in regulating ecosystem functioning and the Earth's climate. Because of this, it is imperative that that Earth-system, climate and ecosystem-level models be able to accurately predict variations in rates of leaf respiration. In the field of photosynthesis research, the F/vC/B model has enabled modellers to accurately predict variations in photosynthesis through time and space. By contrast, we lack an equivalent biochemical model to predict variations in leaf respiration. Consequently, we need to rely on phenomenological approaches to model variations in respiration across the Earth's surface. Such approaches require that we develop a thorough understanding of how rates of respiration vary among species and whether global environmental gradients play a role in determining variations in leaf respiration. Dealing with these issues requires that data sets be assembled on rates of leaf respiration in biomes across the Earth's surface. In this talk, I will use a newly-assembled global database on leaf respiration and associated traits (including photosynthesis) to highlight variation in leaf respiration (and the balance between respiration and photosynthesis) across global gradients in growth temperature and aridity.

Effect of nitrogen supply on leaf appearance, leaf growth, leaf nitrogen economy and photosynthetic capacity in maize (Zea mays L.)

NARCIS (Netherlands)

Vos, J.; Putten, van der P.E.L.; Birch, C.J.

2005-01-01

Leaf area growth and nitrogen concentration per unit leaf area, Na (g m-2 N) are two options plants can use to adapt to nitrogen limitation. Previous work indicated that potato (Solanum tuberosum L.) adapts the size of leaves to maintain Na and photosynthetic capacity per unit leaf area. This paper

SU-F-T-350: Continuous Leaf Optimization (CLO) for IMRT Leaf Sequencing

Energy Technology Data Exchange (ETDEWEB)

Long, T; Chen, M; Jiang, S; Lu, W [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: To study a new step-and-shoot IMRT leaf sequencing model that avoids the two main pitfalls of conventional leaf sequencing: (1) target fluence being stratified into a fixed number of discrete levels and/or (2) aperture leaf positions being restricted to a discrete set of locations. These assumptions induce error into the sequence or reduce the feasible region of potential plans, respectively. Methods: We develop a one-dimensional (single leaf pair) methodology that does not make assumptions (1) or (2) that can be easily extended to a multi-row model. The proposed continuous leaf optimization (CLO) methodology takes in an existing set of apertures and associated intensities, or solution “seed,” and improves the plan without the restrictiveness of 1or (2). It then uses a first-order descent algorithm to converge onto a locally optimal solution. A seed solution can come from models that assume (1) and (2), thus allowing the CLO model to improve upon existing leaf sequencing methodologies. Results: The CLO model was applied to 208 generated target fluence maps in one dimension. In all cases for all tested sequencing strategies, the CLO model made improvements on the starting seed objective function. The CLO model also was able to keep MUs low. Conclusion: The CLO model can improve upon existing leaf sequencing methods by avoiding the restrictions of (1) and (2). By allowing for more flexible leaf positioning, error can be reduced when matching some target fluence. This study lays the foundation for future models and solution methodologies that can incorporate continuous leaf positions explicitly into the IMRT treatment planning model. Supported by Cancer Prevention & Research Institute of Texas (CPRIT) - ID RP150485.

Artemisia umbelliformis Lam. and Génépi Liqueur: Volatile Profile as Diagnostic Marker for Geographic Origin and To Predict Liqueur Safety.

Science.gov (United States)

Boggia, Lorenzo; Pignata, Giuseppe; Sgorbini, Barbara; Colombo, Maria Laura; Marengo, Arianna; Casale, Manuela; Nicola, Silvana; Bicchi, Carlo; Rubiolo, Patrizia

2017-04-05

Artemisia umbelliformis, commonly known as "white génépi", is characterized by a volatile fraction rich in α- and β-thujones, two monoterpenoids; under European Union (EU) regulations these are limited to 35 mg/L in Artemisia-based beverages because of their recognized activity on the human central nervous system. This study reports the results of an investigation to define the geographical origin and thujone content of individual plants of A. umbelliformis from different geographical sites, cultivated experimentally at a single site, and to predict the thujone content in the resulting liqueurs through their volatile fraction. Headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) and non-separative HS-SPME-MS were used as analytical platforms to create a database suitable for chemometric description and prediction through linear discriminant analysis (LDA). HS-SPME-MS was applied to shorten analysis time. With both approaches, a diagnostic prediction of (i) plant geographical origin and (ii) thujone content of plant-related liqueurs could be made.

On the temporal variation of leaf magnetic parameters: seasonal accumulation of leaf-deposited and leaf-encapsulated particles of a roadside tree crown.

Science.gov (United States)

Hofman, Jelle; Wuyts, Karen; Van Wittenberghe, Shari; Samson, Roeland

2014-09-15

Understanding the accumulation behaviour of atmospheric particles inside tree leaves is of great importance for the interpretation of biomagnetic monitoring results. In this study, we evaluated the temporal variation of the saturation isothermal remanent magnetisation (SIRM) of leaves of a roadside urban Platanus × acerifolia Willd. tree in Antwerp, Belgium. We hereby examined the seasonal development of the total leaf SIRM signal as well as the leaf-encapsulated fraction of the deposited dust, by washing the leaves before biomagnetic analysis. On average 38% of the leaf SIRM signal was exhibited by the leaf-encapsulated particles. Significant correlations were found between the SIRM and the cumulative daily average atmospheric PM10 and PM2.5 measurements. Moreover, a steady increase of the SIRM throughout the in-leaf season was observed endorsing the applicability of biomagnetic monitoring as a proxy for the time-integrated PM exposure of urban tree leaves. Strongest correlations were obtained for the SIRM of the leaf-encapsulated particles which confirms the dynamic nature of the leaf surface-accumulated particles. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of Wind on the Relation of Leaf N, P Stoichiometry with Leaf Morphology in Quercus Species

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Peng Zhang

2018-02-01

Full Text Available Leaf nitrogen (N and phosphorus (P stoichiometry correlates closely to leaf morphology, which is strongly impacted by wind at multiple scales. However, it is not clear how leaf N, P stoichiometry and its relationship to leaf morphology changes with wind load. We determined the leaf N and P concentrations and leaf morphology—including specific leaf area (SLA and leaf dissection index (LDI—for eight Quercus species under a simulated wind load for seven months. Leaf N and P concentrations increased significantly under these conditions for Quercus acutissima, Quercus rubra, Quercus texana, and Quercus palustris—which have elliptic leaves—due to their higher N, P requirements and a resultant leaf biomass decrease, which is a tolerance strategy for Quercus species under a wind load. Leaf N:P was relatively stable under wind for all species, which supports stoichiometric homeostasis. Leaf N concentrations showed a positive correlation to SLA, leaf N and P concentrations showed positive correlations to LDI under each wind treatment, and the slope of correlations was not affected by wind, which indicates synchronous variations between leaf stoichiometry and leaf morphology under wind. However, the intercept of correlations was affected by wind, and leaf N and P use efficiency decreased under the wind load, which suggests that the Quercus species changes from “fast investment-return” in the control to “slow investment-return” under windy conditions. These results will be valuable to understanding functional strategies for plants under varying wind loads, especially synchronous variations in leaf traits along a wind gradient.

Are leaf physiological traits related to leaf water isotopic enrichment in restinga woody species?

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BRUNO H.P. ROSADO

2013-09-01

Full Text Available During plant-transpiration, water molecules having the lighter stable isotopes of oxygen and hydrogen evaporate and diffuse at a faster rate through the stomata than molecules having the heavier isotopes, which cause isotopic enrichment of leaf water. Although previous models have assumed that leaf water is well-mixed and isotopically uniform, non-uniform stomatal closure, promoting different enrichments between cells, and different pools of water within leaves, due to morpho-physiological traits, might lead to inaccuracies in isotopic models predicting leaf water enrichment. We evaluate the role of leaf morpho-physiological traits on leaf water isotopic enrichment in woody species occurring in a coastal vegetation of Brazil known as restinga. Hydrogen and oxygen stable isotope values of soil, plant stem and leaf water and leaf traits were measured in six species from restinga vegetation during a drought and a wet period. Leaf water isotopic enrichment relative to stem water was more homogeneous among species during the drought in contrast to the wet period suggesting convergent responses to deal to temporal heterogeneity in water availability. Average leaf water isotopic enrichment relative to stem water during the drought period was highly correlated with relative apoplastic water content. We discuss this observation in the context of current models of leaf water isotopic enrichment as a function of the Péclet effect. We suggest that future studies should include relative apoplastic water content in isotopic models.

Are leaf physiological traits related to leaf water isotopic enrichment in restinga woody species?

Science.gov (United States)

Rosado, Bruno H P; De Mattos, Eduardo A; Sternberg, Leonel Da S L

2013-09-01

During plant-transpiration, water molecules having the lighter stable isotopes of oxygen and hydrogen evaporate and diffuse at a faster rate through the stomata than molecules having the heavier isotopes, which cause isotopic enrichment of leaf water. Although previous models have assumed that leaf water is well-mixed and isotopically uniform, non-uniform stomatal closure, promoting different enrichments between cells, and different pools of water within leaves, due to morpho-physiological traits, might lead to inaccuracies in isotopic models predicting leaf water enrichment. We evaluate the role of leaf morpho-physiological traits on leaf water isotopic enrichment in woody species occurring in a coastal vegetation of Brazil known as restinga. Hydrogen and oxygen stable isotope values of soil, plant stem and leaf water and leaf traits were measured in six species from restinga vegetation during a drought and a wet period. Leaf water isotopic enrichment relative to stem water was more homogeneous among species during the drought in contrast to the wet period suggesting convergent responses to deal to temporal heterogeneity in water availability. Average leaf water isotopic enrichment relative to stem water during the drought period was highly correlated with relative apoplastic water content. We discuss this observation in the context of current models of leaf water isotopic enrichment as a function of the Péclet effect. We suggest that future studies should include relative apoplastic water content in isotopic models.

How do leaf veins influence the worldwide leaf economic spectrum? Review and synthesis.

Science.gov (United States)

Sack, Lawren; Scoffoni, Christine; John, Grace P; Poorter, Hendrik; Mason, Chase M; Mendez-Alonzo, Rodrigo; Donovan, Lisa A

2013-10-01

Leaf vein traits are implicated in the determination of gas exchange rates and plant performance. These traits are increasingly considered as causal factors affecting the 'leaf economic spectrum' (LES), which includes the light-saturated rate of photosynthesis, dark respiration, foliar nitrogen concentration, leaf dry mass per area (LMA) and leaf longevity. This article reviews the support for two contrasting hypotheses regarding a key vein trait, vein length per unit leaf area (VLA). Recently, Blonder et al. (2011, 2013) proposed that vein traits, including VLA, can be described as the 'origin' of the LES by structurally determining LMA and leaf thickness, and thereby vein traits would predict LES traits according to specific equations. Careful re-examination of leaf anatomy, published datasets, and a newly compiled global database for diverse species did not support the 'vein origin' hypothesis, and moreover showed that the apparent power of those equations to predict LES traits arose from circularity. This review provides a 'flux trait network' hypothesis for the effects of vein traits on the LES and on plant performance, based on a synthesis of the previous literature. According to this hypothesis, VLA, while virtually independent of LMA, strongly influences hydraulic conductance, and thus stomatal conductance and photosynthetic rate. We also review (i) the specific physiological roles of VLA; (ii) the role of leaf major veins in influencing LES traits; and (iii) the role of VLA in determining photosynthetic rate per leaf dry mass and plant relative growth rate. A clear understanding of leaf vein traits provides a new perspective on plant function independently of the LES and can enhance the ability to explain and predict whole plant performance under dynamic conditions, with applications towards breeding improved crop varieties.

Type 2C Phosphatase 1 of Artemisia annua L. Is a Negative Regulator of ABA Signaling

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Fangyuan Zhang

2014-01-01

Full Text Available The phytohormone abscisic acid (ABA plays an important role in plant development and environmental stress response. Additionally, ABA also regulates secondary metabolism such as artemisinin in the medicinal plant Artemisia annua L. Although an earlier study showed that ABA receptor, AaPYL9, plays a positive role in ABA-induced artemisinin content improvement, many components in the ABA signaling pathway remain to be elucidated in Artemisia annua L. To get insight of the function of AaPYL9, we isolated and characterized an AaPYL9-interacting partner, AaPP2C1. The coding sequence of AaPP2C1 encodes a deduced protein of 464 amino acids, with all the features of plant type clade A PP2C. Transcriptional analysis showed that the expression level of AaPP2C1 is increased after ABA, salt, and drought treatments. Yeast two-hybrid and bimolecular fluorescence complementation assays (BiFC showed that AaPYL9 interacted with AaPP2C1. The P89S, H116A substitution in AaPYL9 as well as G199D substitution or deletion of the third phosphorylation site-like motif in AaPP2C1 abolished this interaction. Furthermore, constitutive expression of AaPP2C1 conferred ABA insensitivity compared with the wild type. In summary, our data reveals that AaPP2C1 is an AaPYL9-interacting partner and involved in the negative modulation of the ABA signaling pathway in A. annua L.

An evolutionary perspective on leaf economics : Phylogenetics of leaf mass per area in vascular plants

NARCIS (Netherlands)

Flores, Olivier; Garnier, Eric; Wright, Ian J.; Reich, Peter B.; Pierce, Simon; Diaz, Sandra; Pakeman, Robin J.; Rusch, Graciela M.; Bernard-Verdier, Maud; Testi, Baptiste; Bakker, Jan P.; Bekker, Renee M.; Cerabolini, Bruno E. L.; Ceriani, Roberta M.; Cornu, Guillaume; Cruz, Pablo; Delcamp, Matthieu; Dolezal, Jiri; Eriksson, Ove; Fayolle, Adeline; Freitas, Helena; Golodets, Carly; Gourlet-Fleury, Sylvie; Hodgson, John G.; Brusa, Guido; Kleyer, Michael; Kunzmann, Dieter; Lavorel, Sandra; Papanastasis, Vasilios P.; Perez-Harguindeguy, Natalia; Vendramini, Fernanda; Weiher, Evan

In plant leaves, resource use follows a trade-off between rapid resource capture and conservative storage. This "worldwide leaf economics spectrum" consists of a suite of intercorrelated leaf traits, among which leaf mass per area, LMA, is one of the most fundamental as it indicates the cost of leaf

Easy Leaf Area: Automated digital image analysis for rapid and accurate measurement of leaf area.

Science.gov (United States)

Easlon, Hsien Ming; Bloom, Arnold J

2014-07-01

Measurement of leaf areas from digital photographs has traditionally required significant user input unless backgrounds are carefully masked. Easy Leaf Area was developed to batch process hundreds of Arabidopsis rosette images in minutes, removing background artifacts and saving results to a spreadsheet-ready CSV file. • Easy Leaf Area uses the color ratios of each pixel to distinguish leaves and calibration areas from their background and compares leaf pixel counts to a red calibration area to eliminate the need for camera distance calculations or manual ruler scale measurement that other software methods typically require. Leaf areas estimated by this software from images taken with a camera phone were more accurate than ImageJ estimates from flatbed scanner images. • Easy Leaf Area provides an easy-to-use method for rapid measurement of leaf area and nondestructive estimation of canopy area from digital images.

Leaf anatomical traits determine the 18O enrichment of leaf water in coastal halophytes

Science.gov (United States)

Liang, J.; Lin, G., Sr.; Sternberg, L. O.

2017-12-01

Foliar anatomical adaptations to high-salinity environment in mangroves may be recorded by leaf water isotopes. Recent studies observed that a few mangrove species have lower 18O enrichment of leaf water (ΔL) relative to source water than the adjacent terrestrial trees, but what factors actually control this phenomenon is still disputable at present. To resolve this issue, we collected 15 species of true mangrove plants, 14 species of adjacent freshwater trees and 4 species of semi-mangrove plants at five study sites on the southeastern coast of China. Leaf stomatal density and pore size, water content, ΔL and other related leaf physiological traits were determined for the selected leaves of these plants. Our results confirmed that ΔL values of mangroves were generally 3 4 ‰ lower than those of the adjacent freshwater or semi-mangrove species. Higher leaf water per area (LWC) and lower leaf stomatal density (LS) of mangroves played co-dominant roles in lowering ΔL through elongating effective leaf mixing length by about 20%. The Péclet model incorporated by LWC and LS performed well in predicting ΔL. The demonstrated general law between leaf anatomy and ΔL in this paper based on a large pool of species bridges the gap between leaf functional traits and metabolic proxies derived ΔL, which will have considerable potential applications in vegetation succession and reconstruction of paleoclimate research.

Effects of leaf movement on leaf temperature, transpiration and radiation interception in soybean under water stress conditions

International Nuclear Information System (INIS)

Isoda, A.; Wang, P.

2001-01-01

Varietal differences in leaf movement were examined in terms of radiation interception, leaf temperature and transpiration under water stressed conditions. Five cultivars (Qindou 7232, Gaofei 16, Dongnong 87 - 138, 8285 - 8 and 8874) were grown in a concrete frame field in Xinjiang, China. Irrigation treatments (irrigation and no irrigation) were made from the flowering to the pod filling stage. A leaflet in the uppermost layer of the canopy was restrained horizontally. Leaf temperatures, transpiration rate (stem sap flow rate of the main stem per unit leaf area) and intercepted radiation of each leaflet were measured. There were greater varietal differences in leaf movement, leaf temperature and transpiration rate. Leaf temperature seemed to be adjusted by leaf movement and transpiration. The extent to which is adjusted by leaf movement and transpiration differed among the cultivars; leaf temperature was influenced mainly by leaf movement for Gaofei 16 and Dongnong 87 - 138, mainly by transpiration for Qindou 7232 and 8874, and by both for 8285 - 8. Intercepted radiation in the upper two layers of the canopy (20 cm from the uppermost) was greater in the irrigated plot, although the mean values of total leaflets of the irrigated plot were not different as compared to the non-irrigated plot. Although paraheliotropic leaf movement decreased radiation interception, it offers some possibilities for the improvement in radiation penetration within a dense canopy. Cumulated amount of transpiration during a day was compared between the restrained-leaf and the non-leaf-restrained plants in 8874. Paraheliotropic leaf movement reduced water loss by 23% in the irrigated and 71% in the non-irrigated plots

Consequences of pre-inoculation with native arbuscular mycorrhizae on root colonization and survival of Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) seedlings after transplanting

Science.gov (United States)

Bill Eugene Davidson

2015-01-01

Inoculation of seedlings with arbuscular mycorrhizal fungi (AMF) is a common practice aimed at improving seedling establishment. The success of this practice largely depends on the ability of the inoculum to multiply and colonize the growing root system after transplanting. These events were investigated in Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush...

Rapid, high-resolution measurement of leaf area and leaf orientation using terrestrial LiDAR scanning data

International Nuclear Information System (INIS)

Bailey, Brian N; Mahaffee, Walter F

2017-01-01

The rapid evolution of high performance computing technology has allowed for the development of extremely detailed models of the urban and natural environment. Although models can now represent sub-meter-scale variability in environmental geometry, model users are often unable to specify the geometry of real domains at this scale given available measurements. An emerging technology in this field has been the use of terrestrial LiDAR scanning data to rapidly measure the three-dimensional geometry of trees, such as the distribution of leaf area. However, current LiDAR methods suffer from the limitation that they require detailed knowledge of leaf orientation in order to translate projected leaf area into actual leaf area. Common methods for measuring leaf orientation are often tedious or inaccurate, which places constraints on the LiDAR measurement technique. This work presents a new method to simultaneously measure leaf orientation and leaf area within an arbitrarily defined volume using terrestrial LiDAR data. The novelty of the method lies in the direct measurement of the fraction of projected leaf area G from the LiDAR data which is required to relate projected leaf area to total leaf area, and in the new way in which radiation transfer theory is used to calculate leaf area from the LiDAR data. The method was validated by comparing LiDAR-measured leaf area to (1) ‘synthetic’ or computer-generated LiDAR data where the exact area was known, and (2) direct measurements of leaf area in the field using destructive sampling. Overall, agreement between the LiDAR and reference measurements was very good, showing a normalized root-mean-squared-error of about 15% for the synthetic tests, and 13% in the field. (paper)

Leaf endophyte load influences fungal garden development in leaf-cutting ants

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Van Bael Sunshine A

2012-11-01

Full Text Available Abstract Background Previous work has shown that leaf-cutting ants prefer to cut leaf material with relatively low fungal endophyte content. This preference suggests that fungal endophytes exact a cost on the ants or on the development of their colonies. We hypothesized that endophytes may play a role in their host plants’ defense against leaf-cutting ants. To measure the long-term cost to the ant colony of fungal endophytes in their forage material, we conducted a 20-week laboratory experiment to measure fungal garden development for colonies that foraged on leaves with low or high endophyte content. Results Colony mass and the fungal garden dry mass did not differ significantly between the low and high endophyte feeding treatments. There was, however, a marginally significant trend toward greater mass of fungal garden per ant worker in the low relative to the high endophyte treatment. This trend was driven by differences in the fungal garden mass per worker from the earliest samples, when leaf-cutting ants had been foraging on low or high endophyte leaf material for only 2 weeks. At two weeks of foraging, the mean fungal garden mass per worker was 77% greater for colonies foraging on leaves with low relative to high endophyte loads. Conclusions Our data suggest that the cost of endophyte presence in ant forage material may be greatest to fungal colony development in its earliest stages, when there are few workers available to forage and to clean leaf material. This coincides with a period of high mortality for incipient colonies in the field. We discuss how the endophyte-leaf-cutter ant interaction may parallel constitutive defenses in plants, whereby endophytes reduce the rate of colony development when its risk of mortality is greatest.

Easy Leaf Area: Automated Digital Image Analysis for Rapid and Accurate Measurement of Leaf Area

Directory of Open Access Journals (Sweden)

Hsien Ming Easlon

2014-07-01

Full Text Available Premise of the study: Measurement of leaf areas from digital photographs has traditionally required significant user input unless backgrounds are carefully masked. Easy Leaf Area was developed to batch process hundreds of Arabidopsis rosette images in minutes, removing background artifacts and saving results to a spreadsheet-ready CSV file. Methods and Results: Easy Leaf Area uses the color ratios of each pixel to distinguish leaves and calibration areas from their background and compares leaf pixel counts to a red calibration area to eliminate the need for camera distance calculations or manual ruler scale measurement that other software methods typically require. Leaf areas estimated by this software from images taken with a camera phone were more accurate than ImageJ estimates from flatbed scanner images. Conclusions: Easy Leaf Area provides an easy-to-use method for rapid measurement of leaf area and nondestructive estimation of canopy area from digital images.

Automated Leaf Tracking using Multi-view Image Sequences of Maize Plants for Leaf-growth Monitoring

Science.gov (United States)

Das Choudhury, S.; Awada, T.; Samal, A.; Stoerger, V.; Bashyam, S.

2017-12-01

Extraction of phenotypes with botanical importance by analyzing plant image sequences has the desirable advantages of non-destructive temporal phenotypic measurements of a large number of plants with little or no manual intervention in a relatively short period of time. The health of a plant is best interpreted by the emergence timing and temporal growth of individual leaves. For automated leaf growth monitoring, it is essential to track each leaf throughout the life cycle of the plant. Plants are constantly changing organisms with increasing complexity in architecture due to variations in self-occlusions and phyllotaxy, i.e., arrangements of leaves around the stem. The leaf cross-overs pose challenges to accurately track each leaf using single view image sequence. Thus, we introduce a novel automated leaf tracking algorithm using a graph theoretic approach by multi-view image sequence analysis based on the determination of leaf-tips and leaf-junctions in the 3D space. The basis of the leaf tracking algorithm is: the leaves emerge using bottom-up approach in the case of a maize plant, and the direction of leaf emergence strictly alternates in terms of direction. The algorithm involves labeling of the individual parts of a plant, i.e., leaves and stem, following graphical representation of the plant skeleton, i.e., one-pixel wide connected line obtained from the binary image. The length of the leaf is measured by the number of pixels in the leaf skeleton. To evaluate the performance of the algorithm, a benchmark dataset is indispensable. Thus, we publicly release University of Nebraska-Lincoln Component Plant Phenotyping dataset-2 (UNL-CPPD-2) consisting of images of the 20 maize plants captured by visible light camera of the Lemnatec Scanalyzer 3D high throughout plant phenotyping facility once daily for 60 days from 10 different views. The dataset is aimed to facilitate the development and evaluation of leaf tracking algorithms and their uniform comparisons.

Measurement for the MLC leaf velocity profile by considering the leaf leakage using a radiographic film

International Nuclear Information System (INIS)

Chow, James C L; Grigorov, Grigor N

2006-01-01

A method to measure the velocity profile of a multi-leaf collimator (MLC) leaf along its travel range using a radiographic film is reported by considering the intra-leaf leakage. A specific dynamic MLC field with leaves travelling from the field edge to the isocentre line was designed. The field was used to expose a radiographic film, which was then scanned, and the dose profile along the horizontal leaf axis was measured. The velocity at a sampling point on the film can be calculated by considering the horizontal distance between the sampling point and the isocentre line, dose at the sampling point, dose rate of the linear accelerator, the total leaf travel time from the field edge to isocentre line and the pre-measured dose rate of leaf leakage. With the leaf velocities and velocity profiles for all MLC leaves measured routinely, a comprehensive and simple QA for the MLC can be set up to test the consistency of the leaf velocity performance which is essential to the IMRT delivery using a sliding window technique. (note)

Evaluación y control de calidad de la tintura homeopática de Artemisia absinthium L.

OpenAIRE

Chalala Vázquez, Madeline; García García, Dinah María; Crespo Valiente, Maritza; Rodríguez Ferradá, Carlos A; Hechevarría Sosa, Isabel

2004-01-01

El presente trabajo tiene como objetivo fundamental el estudio de la evaluación y control de calidad de la tintura homeopática de Artemisia absinthium L. cultivada en las condiciones de Cuba, especie de amplio uso y reconocido valor terapéutico. En la investigación se utilizaron las partes aéreas y floridas frescas de dicha planta. Se obtuvieron 13 lotes de tintura según el método de la escuela francesa; a un título de etanol del 65 % v/v y se establecieron los indicadores de calidad tales co...

Identification of Repellent and Insecticidal Constituents of the Essential Oil of Artemisia rupestris L. Aerial Parts against Liposcelis bostrychophila Badonnel

OpenAIRE

Liu, Xin; Li, Yin; Li, He; Deng, Zhi; Zhou, Ligang; Liu, Zhi; Du, Shu

2013-01-01

The aim of this research was to determine the chemical composition and insecticidal and repellent activity of the essential oil of Artemisia rupestris L. aerial parts against the booklice Liposcelis bostrychophila Badonnel and isolation of insecticidal and repellent constituents from the essential oil. The essential oil of A. rupestris was obtained by hydrodistillation and analyzed by GC-MS. A total of 30 components of the essential oil of A. rupestris was identified and the principal compoun...

Evaluation of Cytotoxicity and Antifertility Effect of Artemisia kopetdaghensis

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Davood Oliaee

2014-01-01

Full Text Available To date, there is no report on safety of Artemisia Kopetdaghensis. This study aimed to determine the possible undesirable effects of A. Kopetdaghensis on reproduction of female rats. The pregnant rats were treated (i.p. with vehicle or 200 and 400 mg/kg of A. Kopetdaghensis hydroalcoholic extract from the 2nd to 8th day of pregnancy. Then, number and weight of neonates, duration of pregnancy, and percent of dead fetuses were determined. Also, cytotoxicity of this plant was tested using fibroblast (L929 and ovary (Cho cell lines. The A. Kopetdaghensis had no significant effect on duration of pregnancy, average number of neonates, and weight of neonates. However, administration of 200 and 400 mg/kg of the extract led to 30 and 44% abortion in animals, respectively. The extract at concentrations ≥200 μg/mL significantly (P<0.001 inhibited the proliferation of L929 fibroblast cells. Regarding the Cho cells, the extract induced toxicity only at concentration of 800 μg/mL (P<0.01. Our results showed that continuous consumption of A. Kopetdaghensis in pregnancy may increase the risk of abortion and also may have toxic effect on some cells.

Volatile Components of the Essential Oil of Artemisia montana and Their Sedative Effects.

Science.gov (United States)

Kunihiro, Kento; Myoda, Takao; Tajima, Noriaki; Gotoh, Kotaro; Kaneshima, Tai; Someya, Takao; Toeda, Kazuki; Fujimori, Takane; Nishizawa, Makoto

2017-08-01

The sedative effects of volatile components in the essential oil of Artemisia montana ("Yomogi") were investigated and measured using gas chromatography-mass spectrometry (GC-MS). Major components identified included 1,8-cineol, camphor, borneol, α-piperitone, and caryophyllene oxide. Among them, 1,8-cineol exhibited the highest flavor dilution (FD) value in an aroma extract dilution analysis (AEDA), followed by borneol, o-cymene, β-thujone, and bornyl acetate. The sedative effects of yomogi oil aroma were evaluated by sensory testing, analysis of salivary α-amylase activity, and measurement of relative fluctuation of oxygenated hemoglobin concentration in the brain using near-infrared spectroscopy (NIRS). All results indicated the stress-reducing effects of the essential oil following nasal exposure, and according to the NIRS analysis, 1,8-cineol is likely responsible for the sedative effects of yomogi oil.

Geometric leaf placement strategies

International Nuclear Information System (INIS)

Fenwick, J D; Temple, S W P; Clements, R W; Lawrence, G P; Mayles, H M O; Mayles, W P M

2004-01-01

Geometric leaf placement strategies for multileaf collimators (MLCs) typically involve the expansion of the beam's-eye-view contour of a target by a uniform MLC margin, followed by movement of the leaves until some point on each leaf end touches the expanded contour. Film-based dose-distribution measurements have been made to determine appropriate MLC margins-characterized through an index d 90 -for multileaves set using one particular strategy to straight lines lying at various angles to the direction of leaf travel. Simple trigonometric relationships exist between different geometric leaf placement strategies and are used to generalize the results of the film work into d 90 values for several different strategies. Measured d 90 values vary both with angle and leaf placement strategy. A model has been derived that explains and describes quite well the observed variations of d 90 with angle. The d 90 angular variations of the strategies studied differ substantially, and geometric and dosimetric reasoning suggests that the best strategy is the one with the least angular variation. Using this criterion, the best straightforwardly implementable strategy studied is a 'touch circle' approach for which semicircles are imagined to be inscribed within leaf ends, the leaves being moved until the semicircles just touch the expanded target outline

Apparent over-investment in leaf venation relaxes leaf morphological constraints on photosynthesis in arid habitats

Science.gov (United States)

de Boer, Hugo; Drake, Paul; Veneklaas, Erik

2017-04-01

The close relationship between leaf water status and stomatal conductance implies that the hydraulic architecture of leaves poses an important constraint on transpiration, specifically in arid environments with high evaporative demands. However, it remains uncertain how morphological, hydraulic and photosynthetic traits are coordinated to achieve optimal leaf functioning in arid environments. Critical is that leaf veins supply the mesophyll with water that evaporates when stomata are open to allow CO2 uptake for photosynthesis. Theoretical analyses suggest that water is optimally distributed in the mesophyll when the lateral distance between veins (dx) is equal to the distance from these veins to the epidermis (dy), expressed as dx:dy≈1. Although this theory is supported by observations on many derived angiosperms, we hypothesize that plants in arid environments may reduce dx:dy below unity owing to climate-specific functional adaptations of increased leaf thickness and increased vein density. To test our hypothesis we assembled leaf hydraulic, morphological and photosynthetic traits of 68 species from the Eucalyptus and Corymbia genera (termed eucalypts) along an aridity gradient in southwestern Australia. We inferred the potential gas exchange advantage of reducing dx beyond dy using a model that links leaf morphology and hydraulics to photosynthesis. Our observations reveal that eucalypts in arid environments have thick amphistomatous leaves with high vein densities, resulting in dx:dy ratios that range from 1.6 to 0.15 along the aridity gradient. Our model suggests that as leaves become thicker, the effect of reducing dx beyond dy is to offset the reduction in leaf gas exchange that would result from maintaining dx:dy at unity. This apparent over-investment in leaf venation may be explained from the selective pressure of aridity, under which traits associated with long leaf lifespan, high hydraulic and thermal capacitances, and high potential rates of leaf

NARROW LEAF 7 controls leaf shape mediated by auxin in rice

NARCIS (Netherlands)

Fujino, Kenji; Matsuda, Yasuyuki; Ozawa, Kenjirou; Nishimura, Takeshi; Koshiba, Tomokazu; Fraaije, Marco W.; Sekiguchi, Hiroshi

Elucidation of the genetic basis of the control of leaf shape could be of use in the manipulation of crop traits, leading to more stable and increased crop production. To improve our understanding of the process controlling leaf shape, we identified a mutant gene in rice that causes a significant

Scaling up stomatal conductance from leaf to canopy using a dual-leaf model for estimating crop evapotranspiration.

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Risheng Ding

Full Text Available The dual-source Shuttleworth-Wallace model has been widely used to estimate and partition crop evapotranspiration (λET. Canopy stomatal conductance (Gsc, an essential parameter of the model, is often calculated by scaling up leaf stomatal conductance, considering the canopy as one single leaf in a so-called "big-leaf" model. However, Gsc can be overestimated or underestimated depending on leaf area index level in the big-leaf model, due to a non-linear stomatal response to light. A dual-leaf model, scaling up Gsc from leaf to canopy, was developed in this study. The non-linear stomata-light relationship was incorporated by dividing the canopy into sunlit and shaded fractions and calculating each fraction separately according to absorbed irradiances. The model includes: (1 the absorbed irradiance, determined by separately integrating the sunlit and shaded leaves with consideration of both beam and diffuse radiation; (2 leaf area for the sunlit and shaded fractions; and (3 a leaf conductance model that accounts for the response of stomata to PAR, vapor pressure deficit and available soil water. In contrast to the significant errors of Gsc in the big-leaf model, the predicted Gsc using the dual-leaf model had a high degree of data-model agreement; the slope of the linear regression between daytime predictions and measurements was 1.01 (R2 = 0.98, with RMSE of 0.6120 mm s-1 for four clear-sky days in different growth stages. The estimates of half-hourly λET using the dual-source dual-leaf model (DSDL agreed well with measurements and the error was within 5% during two growing seasons of maize with differing hydrometeorological and management strategies. Moreover, the estimates of soil evaporation using the DSDL model closely matched actual measurements. Our results indicate that the DSDL model can produce more accurate estimation of Gsc and λET, compared to the big-leaf model, and thus is an effective alternative approach for estimating and

Seasonality of Leaf Carbon Isotopic Composition and Leaf Water Isotopic Enrichment in a Mixed Evergreen Forest in Southern California

Science.gov (United States)

Santiago, L. S.; Sickman, J. O.; Goulden, M.; DeVan, C.; Pasquini, S. C.; Pivovaroff, A. L.

2011-12-01

Leaf carbon isotopic composition and leaf water isotopic enrichment reflect physiological processes and are important for linking local and regional scale processes to global patterns. We investigated how seasonality affects the isotopic composition of bulk leaf carbon, leaf sugar carbon, and leaf water hydrogen under a Mediterranean climate. Leaf and stem samples were collected monthly from four tree species (Calocedrus decurrens, Pinus lambertiana, Pinus ponderosa, and Quercus chrysolepis) at the James San Jacinto Mountain Reserve in southern California. Mean monthly bulk leaf carbon isotopic composition varied from -34.5 % in P. ponderosa to -24.7 % in P. lambertiana and became more depleted in 13C from the spring to the summer. Mean monthly leaf sugar varied from -29.3 % in P. ponderosa to -21.8 % in P. lambertiana and was enriched in 13C during the winter, spring and autumn, but depleted during the mid-summer. Leaf water hydrogen isotopic composition was 28.4 to 68.8 % more enriched in deuterium than source water and this enrichment was greater as seasonal drought progressed. These data indicate that leaf carbon and leaf water hydrogen isotopic composition provide sensitive measures that connect plant physiological processes to short-term climatic variability.

Leaf sequencing algorithms for segmented multileaf collimation

International Nuclear Information System (INIS)

Kamath, Srijit; Sahni, Sartaj; Li, Jonathan; Palta, Jatinder; Ranka, Sanjay

2003-01-01

The delivery of intensity-modulated radiation therapy (IMRT) with a multileaf collimator (MLC) requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC during radiation delivery. It is imperative that the fluence map delivered using the leaf sequence file is as close as possible to the fluence map generated by the dose optimization algorithm, while satisfying hardware constraints of the delivery system. Optimization of the leaf sequencing algorithm has been the subject of several recent investigations. In this work, we present a systematic study of the optimization of leaf sequencing algorithms for segmental multileaf collimator beam delivery and provide rigorous mathematical proofs of optimized leaf sequence settings in terms of monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation constraint and leaf interdigitation constraint. Our analytical analysis shows that leaf sequencing based on unidirectional movement of the MLC leaves is as MU efficient as bidirectional movement of the MLC leaves

Leaf sequencing algorithms for segmented multileaf collimation

Energy Technology Data Exchange (ETDEWEB)

Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States)

2003-02-07

The delivery of intensity-modulated radiation therapy (IMRT) with a multileaf collimator (MLC) requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC during radiation delivery. It is imperative that the fluence map delivered using the leaf sequence file is as close as possible to the fluence map generated by the dose optimization algorithm, while satisfying hardware constraints of the delivery system. Optimization of the leaf sequencing algorithm has been the subject of several recent investigations. In this work, we present a systematic study of the optimization of leaf sequencing algorithms for segmental multileaf collimator beam delivery and provide rigorous mathematical proofs of optimized leaf sequence settings in terms of monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation constraint and leaf interdigitation constraint. Our analytical analysis shows that leaf sequencing based on unidirectional movement of the MLC leaves is as MU efficient as bidirectional movement of the MLC leaves.

Study on creation of an indocalamus leaf flavor

Directory of Open Access Journals (Sweden)

Guangyong ZHU

2015-01-01

Full Text Available AbstractFlavors represent a small but significant segment of food industry. Sensory characteristics play an important role in the process of consumer acceptance and preference. Indocalamus leaf takes on a pleasant odor and indocalamus leaf flavor can be used in many products. However, indocalamus leaf flavor formula has not been reported. Therefore, developing an indocalamus leaf flavor is of significant interests. Note is a distinct flavor or odor characteristic. This paper concentrates on preparation and creation of indocalamus leaf flavor according to the notes of indocalamus leaf. The notes were obtained by smelling indocalamus leaf, and the results showed that the notes of indocalamus leaf flavor can be classified as: green-leafy note, sweet note, beany note, aldehydic note, waxy note, woody note, roast note, creamy note, and nutty note. According to the notes of indocalamus leaf odor, a typical indocalamus leaf flavor formula was obtained. The indocalamus leaf flavor blended is pleasant, harmonious, and has characteristics of indocalamus leaf odor.

The dosimetric impact of leaf interdigitation and leaf width on VMAT treatment planning in Pinnacle: comparing Pareto fronts

International Nuclear Information System (INIS)

Van Kesteren, Z; Janssen, T M; Damen, E; Van Vliet-Vroegindeweij, C

2012-01-01

To evaluate in an objective way the effect of leaf interdigitation and leaf width on volumetric modulated arc therapy plans in Pinnacle. Three multileaf collimators (MLCs) were modeled: two 10 mm leaf width MLCs, with and without interdigitating leafs, and a 5 mm leaf width MLC with interdigitating leafs. Three rectum patients and three prostate patients were used for the planning study. In order to compare treatment techniques in an objective way, a Pareto front comparison was carried out. 200 plans were generated in an automated way, per patient per MLC model, resulting in a total of 3600 plans. From these plans, Pareto-optimal plans were selected which were evaluated for various dosimetric variables. The capability of leaf interdigitation showed little dosimetric impact on the treatment plans, when comparing the 10 mm leaf width MLC with and without leaf interdigitation. When comparing the 10 mm leaf width MLC with the 5 mm leaf width MLC, both with interdigitating leafs, improvement in plan quality was observed. For both patient groups, the integral dose was reduced by 0.6 J for the thin MLC. For the prostate patients, the mean dose to the anal sphincter was reduced by 1.8 Gy and the conformity of the V 95% was reduced by 0.02 using the thin MLC. The V 65% of the rectum was reduced by 0.1% and the dose homogeneity with 1.5%. For rectum patients, the mean dose to the bowel was reduced by 1.4 Gy and the mean dose to the bladder with 0.8 Gy for the thin MLC. The conformity of the V 95% was equivalent for the 10 and 5 mm leaf width MLCs for the rectum patients. We have objectively compared three types of MLCs in a planning study for prostate and rectum patients by analyzing Pareto-optimal plans which were generated in an automated way. Interdigitation of MLC leafs does not generate better plans using the SmartArc algorithm in Pinnacle. Changing the MLC leaf width from 10 to 5 mm generates better treatment plans although the clinical relevance remains to be proven

The dosimetric impact of leaf interdigitation and leaf width on VMAT treatment planning in Pinnacle: comparing Pareto fronts.

Science.gov (United States)

van Kesteren, Z; Janssen, T M; Damen, E; van Vliet-Vroegindeweij, C

2012-05-21

To evaluate in an objective way the effect of leaf interdigitation and leaf width on volumetric modulated arc therapy plans in Pinnacle. Three multileaf collimators (MLCs) were modeled: two 10 mm leaf width MLCs, with and without interdigitating leafs, and a 5 mm leaf width MLC with interdigitating leafs. Three rectum patients and three prostate patients were used for the planning study. In order to compare treatment techniques in an objective way, a Pareto front comparison was carried out. 200 plans were generated in an automated way, per patient per MLC model, resulting in a total of 3600 plans. From these plans, Pareto-optimal plans were selected which were evaluated for various dosimetric variables. The capability of leaf interdigitation showed little dosimetric impact on the treatment plans, when comparing the 10 mm leaf width MLC with and without leaf interdigitation. When comparing the 10 mm leaf width MLC with the 5 mm leaf width MLC, both with interdigitating leafs, improvement in plan quality was observed. For both patient groups, the integral dose was reduced by 0.6 J for the thin MLC. For the prostate patients, the mean dose to the anal sphincter was reduced by 1.8 Gy and the conformity of the V(95%) was reduced by 0.02 using the thin MLC. The V(65%) of the rectum was reduced by 0.1% and the dose homogeneity with 1.5%. For rectum patients, the mean dose to the bowel was reduced by 1.4 Gy and the mean dose to the bladder with 0.8 Gy for the thin MLC. The conformity of the V(95%) was equivalent for the 10 and 5 mm leaf width MLCs for the rectum patients. We have objectively compared three types of MLCs in a planning study for prostate and rectum patients by analyzing Pareto-optimal plans which were generated in an automated way. Interdigitation of MLC leafs does not generate better plans using the SmartArc algorithm in Pinnacle. Changing the MLC leaf width from 10 to 5 mm generates better treatment plans although the clinical relevance remains

DIFFERENCES IN LEAF GAS EXCHANGE AND LEAF CHARACTERISTICS BETWEEN TWO ALMOND CULTIVARS

Directory of Open Access Journals (Sweden)

George D. Nanos

2013-12-01

Full Text Available Leaf chlorophyll content, specific leaf weight (SLW, photosynthetic and transpiration rates, stomatal functioning, water use efficiency and quantum yield were assessed during the kernel filling period for two consecutive years in order to understand tissue-centered physiological profile differences between two commercial almond cultivars, ‘Ferragnès’ and ‘Texas’. Similar SLWs were observed on the studied cultivars; however, chlorophyll content, net photosynthetic and transpiration rates and stomatal functioning demonstrated statistically significant differences. In both cultivars, an overall decline in the examined parameters towards fruit maturation (i.e. end of the summer was recorded. ‘Ferragnès’ leaves were found to be more efficient in leaf photosynthesis related performance during kernel filling, when irrigated sufficiently, in comparison to ‘Texas’ leaves. Low average values of leaf conductance during summer in ‘Texas’ leaves revealed its potential for adaptation in cool climates and increased carbon assimilation therein for high kernel yield.

Estimating leaf functional traits by inversion of PROSPECT: Assessing leaf dry matter content and specific leaf area in mixed mountainous forest

Science.gov (United States)

Ali, Abebe Mohammed; Darvishzadeh, Roshanak; Skidmore, Andrew K.; Duren, Iris van; Heiden, Uta; Heurich, Marco

2016-03-01

Assessments of ecosystem functioning rely heavily on quantification of vegetation properties. The search is on for methods that produce reliable and accurate baseline information on plant functional traits. In this study, the inversion of the PROSPECT radiative transfer model was used to estimate two functional leaf traits: leaf dry matter content (LDMC) and specific leaf area (SLA). Inversion of PROSPECT usually aims at quantifying its direct input parameters. This is the first time the technique has been used to indirectly model LDMC and SLA. Biophysical parameters of 137 leaf samples were measured in July 2013 in the Bavarian Forest National Park, Germany. Spectra of the leaf samples were measured using an ASD FieldSpec3 equipped with an integrating sphere. PROSPECT was inverted using a look-up table (LUT) approach. The LUTs were generated with and without using prior information. The effect of incorporating prior information on the retrieval accuracy was studied before and after stratifying the samples into broadleaf and conifer categories. The estimated values were evaluated using R2 and normalized root mean square error (nRMSE). Among the retrieved variables the lowest nRMSE (0.0899) was observed for LDMC. For both traits higher R2 values (0.83 for LDMC and 0.89 for SLA) were discovered in the pooled samples. The use of prior information improved accuracy of the retrieved traits. The strong correlation between the estimated traits and the NIR/SWIR region of the electromagnetic spectrum suggests that these leaf traits could be assessed at canopy level by using remotely sensed data.

Comparative Phytochemical Analysis of Essential Oils from Different Biological Parts of Artemisia herba alba and Their Cytotoxic Effect on Cancer Cells

Science.gov (United States)

Tilaoui, Mounir; Ait Mouse, Hassan; Jaafari, Abdeslam; Zyad, Abdelmajid

2015-01-01

Purpose Carrying out the chemical composition and antiproliferative effects against cancer cells from different biological parts of Artemisia herba alba. Methods Essential oils were studied by gas chromatography coupled to mass spectrometry (GC–MS) and their antitumoral activity was tested against P815 mastocytoma and BSR kidney carcinoma cell lines; also, in order to evaluate the effect on normal human cells, oils were tested against peripheral blood mononuclear cells PBMCs. Results Essential oils from leaves and aerial parts (mixture of capitulum and leaves) were mainly composed by oxygenated sesquiterpenes 39.89% and 46.15% respectively; capitulum oil contained essentially monoterpenes (22.86%) and monocyclic monoterpenes (21.48%); esters constituted the major fraction (62.8%) of stem oil. Essential oils of different biological parts studied demonstrated a differential antiproliferative activity against P815 and BSR cancer cells; P815 cells are the most sensitive to the cytotoxic effect. Leaves and capitulum essential oils are more active than aerial parts. Interestingly, no cytotoxic effect of these essential oils was observed on peripheral blood mononuclear cells. Conclusion Our results showed that the chemical composition variability of essential oils depends on the nature of botanical parts of Artemisia herba alba. Furthermore, we have demonstrated that the differential cytotoxic effect depends not only on the essential oils concentration, but also on the target cells and the botanical parts of essential oils used. PMID:26196123

Spectral reflectance relationships to leaf water stress

Science.gov (United States)

Ripple, William J.

1986-01-01

Spectral reflectance data were collected from detached snapbean leaves in the laboratory with a multiband radiometer. Four experiments were designed to study the spectral response resulting from changes in leaf cover, relative water content of leaves, and leaf water potential. Spectral regions included in the analysis were red (630-690 nm), NIR (760-900 nm), and mid-IR (2.08-2.35 microns). The red and mid-IR bands showed sensitivity to changes in both leaf cover and relative water content of leaves. The NIR was only highly sensitive to changes in leaf cover. Results provided evidence that mid-IR reflectance was governed primarily by leaf moisture content, although soil reflectance was an important factor when leaf cover was less than 100 percent. High correlations between leaf water potentials and reflectance were attributed to covariances with relative water content of leaves and leaf cover.

Comparison of leaf-on and leaf-off ALS data for mapping riparian tree species

Science.gov (United States)

Laslier, Marianne; Ba, Antoine; Hubert-Moy, Laurence; Dufour, Simon

2017-10-01

Forest species composition is a fundamental indicator of forest study and management. However, describing forest species composition at large scales and of highly diverse populations remains an issue for which remote sensing can provide significant contribution, in particular, Airborne Laser Scanning (ALS) data. Riparian corridors are good examples of highly valuable ecosystems, with high species richness and large surface areas that can be time consuming and expensive to monitor with in situ measurements. Remote sensing could be useful to study them, but few studies have focused on monitoring riparian tree species using ALS data. This study aimed to determine which metrics derived from ALS data are best suited to identify and map riparian tree species. We acquired very high density leaf-on and leaf-off ALS data along the Sélune River (France). In addition, we inventoried eight main riparian deciduous tree species along the study site. After manual segmentation of the inventoried trees, we extracted 68 morphological and structural metrics from both leaf-on and leaf-off ALS point clouds. Some of these metrics were then selected using Sequential Forward Selection (SFS) algorithm. Support Vector Machine (SVM) classification results showed good accuracy with 7 metrics (0.77). Both leaf-on and leafoff metrics were kept as important metrics for distinguishing tree species. Results demonstrate the ability of 3D information derived from high density ALS data to identify riparian tree species using external and internal structural metrics. They also highlight the complementarity of leaf-on and leaf-off Lidar data for distinguishing riparian tree species.

Specific leaf area estimation from leaf and canopy reflectance through optimization and validation of vegetation indices

NARCIS (Netherlands)

Ali, A.M.; Darvishzadeh, R.; Skidmore, A.K.; van Duren, I.C.

2017-01-01

Specific leaf area (SLA), which is defined as the leaf area per unit of dry leaf mass is an important component when assessing functional diversity and plays a key role in ecosystem modeling, linking plant carbon and water cycles as well as quantifying plant physiological processes. However, studies

Antioxidant properties of extracts from selected plant materials (Caesalpinia spinosa, Perilla frutescens, Artemisia annua and Viola wittrockiana) in vitro and in model food systems

OpenAIRE

Skowyra, Monika

2014-01-01

Phenolic compounds, ubiquitous in plants, are of considerable interest and are increasingly becoming a subject of intensive research due to their bioactive properties such as antioxidant, antimicrobial, anti-mutagenic, anti-viral and anti-inflammatory activity. The objective of this research was to determine the antioxidant activity of extracts from selected plant materials, namely Caesalpinia spinosa, Perilla frutescens, Artemisia annua and Viola wittrockiana Gams. Plant material extracts we...

Leaf hydraulic conductance declines in coordination with photosynthesis, transpiration and leaf water status as soybean leaves age regardless of soil moisture

Science.gov (United States)

Locke, Anna M.; Ort, Donald R.

2014-01-01

Photosynthesis requires sufficient water transport through leaves for stomata to remain open as water transpires from the leaf, allowing CO2 to diffuse into the leaf. The leaf water needs of soybean change over time because of large microenvironment changes over their lifespan, as leaves mature in full sun at the top of the canopy and then become progressively shaded by younger leaves developing above. Leaf hydraulic conductance (K leaf), a measure of the leaf’s water transport capacity, can often be linked to changes in microenvironment and transpiration demand. In this study, we tested the hypothesis that K leaf would decline in coordination with transpiration demand as soybean leaves matured and aged. Photosynthesis (A), stomatal conductance (g s) and leaf water potential (Ψleaf) were also measured at various leaf ages with both field- and chamber-grown soybeans to assess transpiration demand. K leaf was found to decrease as soybean leaves aged from maturity to shading to senescence, and this decrease was strongly correlated with midday A. Decreases in K leaf were further correlated with decreases in g s, although the relationship was not as strong as that with A. Separate experiments investigating the response of K leaf to drought demonstrated no acclimation of K leaf to drought conditions to protect against cavitation or loss of g s during drought and confirmed the effect of leaf age in K leaf observed in the field. These results suggest that the decline of leaf hydraulic conductance as leaves age keeps hydraulic supply in balance with demand without K leaf becoming limiting to transpiration water flux. PMID:25281701

Seagrass leaf element content

NARCIS (Netherlands)

Vonk, J.A.; Smulders, Fee O.H.; Christianen, Marjolijn J.A.; Govers, Laura L.

2017-01-01

Knowledge on the role of seagrass leaf elements and in particular micronutrients and their ranges is limited. We present a global database, consisting of 1126 unique leaf values for ten elements, obtained from literature and unpublished data, spanning 25 different seagrass species from 28 countries.

Estimating leaf area and leaf biomass of open-grown deciduous urban trees

Science.gov (United States)

David J. Nowak

1996-01-01

Logarithmic regression equations were developed to predict leaf area and leaf biomass for open-grown deciduous urban trees based on stem diameter and crown parameters. Equations based on crown parameters produced more reliable estimates. The equations can be used to help quantify forest structure and functions, particularly in urbanizing and urban/suburban areas.

Prophylactic effect of paw-paw leaf and bitter leaf extracts on the ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-18

Aug 18, 2008 ... (ANOVA) and significant means separated using FLSD = LSD procedure as outlined in Obi (2002). RESULTS AND DISCUSSION. In pre-soaking, paw-paw leaf (PL) extract had no significant effect (P > 0.05) on the disease incidence at. 50% anthesis. Bitter leaf (BL) extract had a high signifi- cant effect (P ...

Effects of Artemisia herba-alba essential oils on survival stored cereal pests: Tribolium castaneum (Herbst (Coleoptera, Tenebrionidae and Trogoderma granarium (Everst (Coleoptera, Dermestidae

Directory of Open Access Journals (Sweden)

Ben Slimane Badreddine

2016-05-01

Full Text Available Objective: To assess the chemical components and toxicity of Artemisia herba-alba (A. herbaalba essential oil against two major stored cereal pests, Tribolium castaneum (T. castaneum and Trogoderma granarium (T. granarium. Methods: Two bioassay actions were tasted: repellent and fumigant actions against adult and larvae, respectively, to assess the effect of A. herba-alba essential oil. Results: Gas chromatography-mass spectrometer analyses of the essential oil contained β-thujone (12.50%, α-thujone (8.78%, sabinyl acetate (8.56%, terpinene-4-ol (8.51%, α-terpineol (3.35%, 1,8-cineol (5.45%, γ-terpene (4.82%, camphor (4.52%, dimethylethylbenzene (3.93% and α-terpinene (3.35% as the major components. Fumigant toxicity tests showed that A. herba-alba oil was more toxic than T. granarium (LC50 = 2.09 mg/mL, LC90 = 4.12 mg/mL and T. castaneum (LC50 = 6.39 mg/mL, LC90 = 10.10 mg/mL. Conclusions: This study has highlighted a bioinsecticide activity of A. herba-alba against two insect pests of stored foodstuffs (T. castaneum and T. granarium. The Artemisia essential oil offers an interesting potential insecticide that could be studied more deeply to isolate and identify the active substances, to study their physiological impact on other insects

Artemisia argyi attenuates airway inflammation in ovalbumin-induced asthmatic animals.

Science.gov (United States)

Shin, Na-Rae; Ryu, Hyung-Won; Ko, Je-Won; Park, Sung-Hyeuk; Yuk, Heung-Joo; Kim, Ha-Jung; Kim, Jong-Choon; Jeong, Seong-Hun; Shin, In-Sik

2017-09-14

Artemisia argyi is a traditional herbal medicine in Korea and commonly called as mugwort. It is traditionally used as food source and tea to control abdominal pain, dysmenorrhea, uterine hemorrhage, and inflammation. We investigated the effects of A. argyi (TOTAL) and dehydromatricarin A (DA), its active component on ovalbumin (OVA)-induced allergic asthma. The animals were sensitized on day 0 and 14 by intraperitoneal injection of OVA with aluminum hydroxide. On day 21, 22 and 23 after the initial sensitization, the animals received an airway challenge with OVA for 1h using an ultrasonic nebulizer. TOTAL (50 and 100mg/kg) or DA (10 and 20mg/kg) were administered to mice by oral gavage once daily from day 18-23. Airway hyperresponsiveness (AHR) was measured 24h after final OVA challenge. TOTAL and DA treated animals reduced inflammatory cell counts, cytokines and AHR in asthmatic animals, which was accompanied with inflammatory cell accumulation and mucus hypersecretion. Furthermore, TOTAL and DA significantly declined Erk phosphorylation and the expression of MMP-9 in asthmatic animals. In conclusion, we indicate that Total and DA suppress allergic inflammatory responses caused by OVA challenge. It was considered that A. argyi has a potential for treating allergic asthma. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Joint Leaf chlorophyll and leaf area index retrieval from Landsat data using a regularized model inversion system

Science.gov (United States)

Leaf area index (LAI) and leaf chlorophyll (Chl) content represent key biophysical and biochemical controls on water, energy and carbon exchange processes in the terrestrial biosphere. In combination, LAI and leaf Chl content provide critical information on vegetation density, vitality and photosynt...

Using Leaf Samples to Establish a Library of Tropical Leaf Fingerprints

Science.gov (United States)

Ngo, P.; Nguyen, R.; Anderson, C.; Weiss, P.

2010-12-01

Variation in leaf chemistry is directly expressed in spectroscopic patterns of tropical canopies. The goal of the Spectranomics project is to explore this variation in the hopes of developing a method to measure tropical forest diversity remotely from airborne or space-bound spectroscopy in the future. We analyzed tomato leaves for various chemical compositions to better understand the Spectranomics approach to quantifying chemical data of tropical species. We also compared our data to standard data in each analysis. Our results allow us to give the tomato leaves a chemical signature in which we are able to use to compare to other leaf samples. Using this process, we are able to create a library of leaf signatures and document the variety of tree species in tropical forests around the world.

Leaf density explains variation in leaf mass per area in rice between cultivars and nitrogen treatments.

Science.gov (United States)

Xiong, Dongliang; Wang, Dan; Liu, Xi; Peng, Shaobing; Huang, Jianliang; Li, Yong

2016-05-01

Leaf mass per area (LMA) is an important leaf trait; however, correlations between LMA and leaf anatomical features and photosynthesis have not been fully investigated, especially in cereal crops. The objectives of this study were (a) to investigate the correlations between LMA and leaf anatomical traits; and (b) to clarify the response of LMA to nitrogen supply and its effect on photosynthetic nitrogen use efficiency (PNUE). In the present study, 11 rice varieties were pot grown under sufficient nitrogen (SN) conditions, and four selected rice cultivars were grown under low nitrogen (LN) conditions. Leaf anatomical traits, gas exchange and leaf N content were measured. There was large variation in LMA across selected rice varieties. Regression analysis showed that the variation in LMA was more closely related to leaf density (LD) than to leaf thickness (LT). LMA was positively related to the percentage of mesophyll tissue area (%mesophyll), negatively related to the percentage of epidermis tissue area (%epidermis) and unrelated to the percentage of vascular tissue area (%vascular). The response of LMA to N supplementation was dependent on the variety and was also mainly determined by the response of LD to N. Compared with SN, photosynthesis was significantly decreased under LN, while PNUE was increased. The increase in PNUE was more critical in rice cultivars with a higher LMA under SN supply. Leaf density is the major cause of the variation in LMA across rice varieties and N treatments, and an increase in LMA under high N conditions would aggravate the decrease in PNUE. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

7 CFR 30.2 - Leaf tobacco.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf tobacco. 30.2 Section 30.2 Agriculture... Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO STOCKS AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.2 Leaf...

7 CFR 29.3035 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.3035 Section 29.3035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Leaf structure. The cell development of a leaf as indicated by its porosity or solidity. (See Elements...

7 CFR 29.3526 - Leaf scrap.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling...

7 CFR 29.3034 - Leaf scrap.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and...

7 CFR 29.6022 - Leaf scrap.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results...

Infrared remote sensing for canopy temperature in paddy field and relationship between leaf temperature and leaf color

International Nuclear Information System (INIS)

Wakiyama, Y.

2002-01-01

Infrared remote sensing is used for crop monitoring, for example evaluation of water stress, detection of infected crops and estimation of transpiration and photosynthetic rates. This study was conducted to show another application of remote sensing information. The relationship between rice leaf temperature and chlorophyll content in the leaf blade was investigated by using thermography during the ripening period. The canopy of a rice community fertilized by top dressing was cooler than that not fertilized in a 1999 field experiment. In an experiment using thermocouples to measure leaf temperature, a rice leaf with high chlorophyll content was also cooler than that with a low chlorophyll content. Transpiration resistance and transpiration rate were measured with a porometer. Transpiration rate was higher with increasing chlorophyll content in the leaf blade. Stomatal aperture is related to chlorophyll content in the leaf blade. High degree of stomatal aperture is caused by high chlorophyll content in the leaf blade. As degree of stomatal aperture increases, transpiration rate increases. Therefore the rice leaf got cooler with increasing chlorophyll content in leaf blade. Paddy rice communities with different chlorophyll contents were provided with fertilization of different nitrogen levels on basal and top dressing in a 2000 field experiment. Canopy temperature of the rice community with high chlorophyll content was 0.85°C cooler than that of the rice community with low chlorophyll content. Results of this study revealed that infrared remote sensing could detect difference in chlorophyll contents in rice communities and could be used in fertilizer management in paddy fields. (author)

An analytical approach for optimizing the leaf design of a multi-leaf collimator in a linear accelerator

International Nuclear Information System (INIS)

Topolnjak, R; Heide, U A van der

2008-01-01

In this study, we present an analytical approach for optimizing the leaf design of a multi-leaf collimator (MLC) in a linear accelerator. Because leaf designs vary between vendors, our goal is to characterize and quantify the effects of different compromises which have to be made between performance parameters. Subsequently, an optimal leaf design for an earlier proposed six-bank MLC which combines a high-resolution field-shaping ability with a large field size is determined. To this end a model of the linac is created that includes the following parameters: the source size, the maximum field size, the distance between source and isocenter, and the leaf's design parameters. First, the optimal radius of the leaf tip was found. This optimum was defined by the requirement that the fluence intensity should fall from 80% of the maximum value to 20% in a minimal distance, defining the width of the fluence penumbra. A second requirement was that this penumbra width should be constant when a leaf moves from one side of the field to the other. The geometric, transmission and total penumbra width (80-20%) were calculated depending on the design parameters. The analytical model is in agreement with Elekta, Varian and Siemens collimator designs. For leaves thinner than 4 cm, the transmission penumbra becomes dominant, and for leaves close to the source the geometric penumbra plays a role. Finally, by choosing the leaf thickness of 3.5 cm, 4 cm and 5 cm from the lowest to the highest bank, respectively, an optimal leaf design for a six-bank MLC is achieved

Apparent Overinvestment in Leaf Venation Relaxes Leaf Morphological Constraints on Photosynthesis in Arid Habitats1[OPEN

Science.gov (United States)

de Boer, Hugo J.; Drake, Paul L.; Wendt, Erin; Price, Charles A.; Schulze, Ernst-Detlef; Turner, Neil C.; Nicolle, Dean

2016-01-01

Leaf veins supply the mesophyll with water that evaporates when stomata are open to allow CO2 uptake for photosynthesis. Theoretical analyses suggest that water is optimally distributed in the mesophyll when the lateral distance between veins (dx) is equal to the distance from these veins to the epidermis (dy), expressed as dx:dy ≈ 1. Although this theory is supported by observations of many derived angiosperms, we hypothesize that plants in arid environments may reduce dx:dy below unity owing to climate-specific functional adaptations of increased leaf thickness and increased vein density. To test our hypothesis, we assembled leaf hydraulic, morphological, and photosynthetic traits of 68 species from the Eucalyptus and Corymbia genera (termed eucalypts) along an aridity gradient in southwestern Australia. We inferred the potential gas-exchange advantage of reducing dx beyond dy using a model that links leaf morphology and hydraulics to photosynthesis. Our observations reveal that eucalypts in arid environments have thick amphistomatous leaves with high vein densities, resulting in dx:dy ratios that range from 1.6 to 0.15 along the aridity gradient. Our model suggests that, as leaves become thicker, the effect of reducing dx beyond dy is to offset the reduction in leaf gas exchange that would result from maintaining dx:dy at unity. This apparent overinvestment in leaf venation may be explained from the selective pressure of aridity, under which traits associated with long leaf life span, high hydraulic and thermal capacitances, and high potential rates of leaf water transport confer a competitive advantage. PMID:27784769

7 CFR 29.6023 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.6023 Section 29.6023 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6023 Leaf structure. The cell development of a leaf as indicated by its...

7 CFR 29.1030 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.1030 Section 29.1030 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1030 Leaf structure. The cell development of a leaf as indicated by its porosity. (See...

7 CFR 29.3527 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.3527 Section 29.3527 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3527 Leaf structure. The cell development of a leaf as indicated by its porosity. (See...

Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant.

Science.gov (United States)

Shi, Pei-Jian; Xu, Qiang; Sandhu, Hardev S; Gielis, Johan; Ding, Yu-Long; Li, Hua-Rong; Dong, Xiao-Bo

2015-10-01

The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a -3/2 power between average biomass and density or a -1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.

Effect of Cytokinin and Auxin Treatments on Morphogenesis, Terpenoid Biosynthesis, Photosystem Structural Organization, and Endogenous Isoprenoid Cytokinin Profile in Artemisia alba Turra In Vitro

Czech Academy of Sciences Publication Activity Database

Danova, K.; Motyka, Václav; Todorova, M.; Trendafilova, A.; Krumova, S.; Dobrev, Petre; Andreeva, T.; Oreshkova, T.; Taneva, S.; Evstatieva, L.

2018-01-01

Roč. 37, č. 2 (2018), s. 403-418 ISSN 0721-7595 R&D Projects: GA ČR(CZ) GA16-14649S Institutional support: RVO:61389030 Keywords : Artemisia alba Turra in vitro * Cis- and trans-zeatin * Endogenous cytokinins * Photosystem II and thylakoid morphology * Plant growth regulators * Terpenoid profile of the essential oil Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 2.073, year: 2016

Transcriptional analyses of natural leaf senescence in maize.

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Wei Yang Zhang

Full Text Available Leaf senescence is an important biological process that contributes to grain yield in crops. To study the molecular mechanisms underlying natural leaf senescence, we harvested three different developmental ear leaves of maize, mature leaves (ML, early senescent leaves (ESL, and later senescent leaves (LSL, and analyzed transcriptional changes using RNA-sequencing. Three sets of data, ESL vs. ML, LSL vs. ML, and LSL vs. ESL, were compared, respectively. In total, 4,552 genes were identified as differentially expressed. Functional classification placed these genes into 18 categories including protein metabolism, transporters, and signal transduction. At the early stage of leaf senescence, genes involved in aromatic amino acids (AAAs biosynthetic process and transport, cellular polysaccharide biosynthetic process, and the cell wall macromolecule catabolic process, were up-regulated. Whereas, genes involved in amino acid metabolism, transport, apoptosis, and response to stimulus were up-regulated at the late stage of leaf senescence. Further analyses reveals that the transport-related genes at the early stage of leaf senescence potentially take part in enzyme and amino acid transport and the genes upregulated at the late stage are involved in sugar transport, indicating nutrient recycling mainly takes place at the late stage of leaf senescence. Comparison between the data of natural leaf senescence in this study and previously reported data for Arabidopsis implies that the mechanisms of leaf senescence in maize are basically similar to those in Arabidopsis. A comparison of natural and induced leaf senescence in maize was performed. Athough many basic biological processes involved in senescence occur in both types of leaf senescence, 78.07% of differentially expressed genes in natural leaf senescence were not identifiable in induced leaf senescence, suggesting that differences in gene regulatory network may exist between these two leaf senescence

Effects of Artemisia dracunculus Aqueous Extract on Blood Sugar, Serum Insulin, Triglyceride and Liver Enzymes in Fructose Drinking Water Male Rats

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Mohammad Reza Shahraki

2017-02-01

Full Text Available Background Artemisia are various groups of plants which are used as an herbal medicine in all countries; the present study was designed to evaluate the effects of Artemisia dracunculus (AD leaves aqueous extract on blood sugar, serum insulin, and triglyceride and liver enzymes in Fructose Drinking water (FDW male rats. Methods At the beginning of experiment, 48 Wistar-albino male rats, weighing 200 - 250g were divided into control (C and FDW groups (n = 24. FDW group received FDW (10%, w/v for a month but control group did not receive any agents during the trial period. A half of control and FDW groups received AD L aqueous extract daily during trial period. At the end, animals were anesthetized, sacrificed and blood samples were collected from cervical vessels. Serum insulin, Blood glucose, insulin resistance index, triglyceride and liver enzymes were measured by ordinary methods. Obtained data were analyzed using SPSS-17 via one way ANOVA and Tukey tests. Results Our results showed that serum insulin, blood sugar, insulin resistance index, triglyceride, Aspartate amino transferase (AST and Alanine amino transferase (ALT values in FDW group significantly increased compared to C and C + E groups but these values in group FDW + E were significantly decreases compared to group FDW (P < 0.001. Conclusions Our findings demonstrated that AD L aqueous extract improves blood sugar, serum insulin, insulin resistance index and liver enzymes in rat model.

Ozone induced leaf loss and decreased leaf production of European Holly (Ilex aquifolium L.) over multiple seasons

International Nuclear Information System (INIS)

Ranford, Jonathan; Reiling, Kevin

2007-01-01

European Holly (Ilex aquifolium L.) was used to study the impact of one short (28 day) ozone fumigation episode on leaf production, leaf loss and stomatal conductance (g s ), in order to explore potential longer term effects over 3 growing seasons. Young I. aquifolium plants received an episode of either charcoal-filtered air or charcoal-filtered air with 70 nl l -1 O 3 added for 7 h d -1 over a 28 day period from June 15th 1996, then placed into ambient environment, Stoke-on-Trent, U.K. Data were collected per leaf cohort over the next three growing seasons. Ozone exposure significantly increased leaf loss and stomatal conductance and reduced leaf production over all subsequent seasons. Impact of the initial ozone stress was still detected in leaves that had no direct experimental ozone exposure. This study has shown the potential of ozone to introduce long-term phenological perturbations into ecosystems by influencing productivity over a number of seasons. - Ozone significantly alters Ilex aquifolium leaf production and loss over multiple seasons

Photoperiod-H1 (Ppd-H1) Controls Leaf Size.

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Digel, Benedikt; Tavakol, Elahe; Verderio, Gabriele; Tondelli, Alessandro; Xu, Xin; Cattivelli, Luigi; Rossini, Laura; von Korff, Maria

2016-09-01

Leaf size is a major determinant of plant photosynthetic activity and biomass; however, it is poorly understood how leaf size is genetically controlled in cereal crop plants like barley (Hordeum vulgare). We conducted a genome-wide association scan for flowering time, leaf width, and leaf length in a diverse panel of European winter cultivars grown in the field and genotyped with a single-nucleotide polymorphism array. The genome-wide association scan identified PHOTOPERIOD-H1 (Ppd-H1) as a candidate gene underlying the major quantitative trait loci for flowering time and leaf size in the barley population. Microscopic phenotyping of three independent introgression lines confirmed the effect of Ppd-H1 on leaf size. Differences in the duration of leaf growth and consequent variation in leaf cell number were responsible for the leaf size differences between the Ppd-H1 variants. The Ppd-H1-dependent induction of the BARLEY MADS BOX genes BM3 and BM8 in the leaf correlated with reductions in leaf size and leaf number. Our results indicate that leaf size is controlled by the Ppd-H1- and photoperiod-dependent progression of plant development. The coordination of leaf growth with flowering may be part of a reproductive strategy to optimize resource allocation to the developing inflorescences and seeds. © 2016 American Society of Plant Biologists. All rights reserved.

The Presence of Amorpha-4, 11-Diene Synthase, a Key Enzyme in Artemisinin Production in Ten Artemisia Species

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GA. Garoosi

2011-12-01

Full Text Available Background and the purpose of the study: Artemisinin is one of the most effective medicine against malaria, which is produced naturally by Artemisia annua in low yield. It is produced in a metabolic pathway, in which several genes and gene products are involved. One of the key genes in this pathway is am1, which encodes amorpha-4, 11-diene synthase (ADS, a key enzyme in artemisinin biosynthesis pathway. The aim of this study was to determine the presence of this gene in ten Artemisia species in order to increase the yield of production of Artemisinin. Methods : The experiments were carried out using PCR. Specific primers were designed based on the published am1 gene sequence obtained from A. annua (NCBI, accession number AF327527. Results: The amplification of this gene by the specific primers was considered as a positive sign for the potentiality of artemisinin production. Since the entire am1 gene was not amplified in any of the 10 species used, four parts of the gene, essential in ADS enzyme function, corresponding to a pair site of Arg10-Pro12 in the first 100 amino acids, b aspartate rich motif (DDXXD, c active site final lid and d active site including farnesyl diphosphate (FDP ionization sites and catalytic site in the ADS enzyme, were investigated. Major conclusion: The sequence corresponding to ADS active site was amplified only in A. annua, A. aucheri and A. chamaemelifolia. The negative results obtained with other species could be due to some sequence alteration, such as point mutations or INDELs. We propose A. aucheri and A. chamaemelifolia as two potential candidate species for further characterization, breeding and transferring am1 gene for artemisinin overproduction.

Bioactivity of essential oil of Artemisia argyi Lévl. et Van. and its main compounds against Lasioderma serricorne.

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Zhang, Wen-Juan; You, Chun-Xue; Yang, Kai; Chen, Ran; Wang, Ying; Wu, Yan; Geng, Zhu-Feng; Chen, Hai-Ping; Jiang, Hai-Yan; Su, Yang; Lei, Ning; Ma, Ping; Du, Shu-Shan; Deng, Zhi-Wei

2014-01-01

Artemisia argyi Lévl. et Van., a perennial herb with a strong volatile odor, is widely distrbuted in the world. Essential oil obtained from Artemisia argyi was analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 32 components representing 91.74% of the total oil were identified and the main compounds in the oil were found to be eucalyptol (22.03%), β-pinene (14.53%), β-caryophyllene (9.24%) and (-)-camphor (5.45%). With a further isolation, four active constituents were obtained from the essential oil and identified as eucalyptol, β-pinene, β-caryophyllene and camphor. The essential oil and the four isolated compounds exhibited potential bioactivity against Lasioderma serricorne adults. In the progress of assay, it showed that the essential oil, camphor, eucalyptol, β-caryophyllene and β-pinene exhibited strong contact toxicity against L. serricorne adults with LD50 values of 6.42, 11.30, 15.58, 35.52, and 65.55 μg/adult, respectively. During the fumigant toxicity test, the essential oil, eucalyptol and camphor showed stronger fumigant toxicity against L. serricorne adults than β-pinene (LC50 = 29.03 mg/L air) with LC50 values of 8.04, 5.18 and 2.91 mg/L air. Moreover, the essential oil, eucalyptol, β-pinene and camphor also exhibited the strong repellency against L. serricorne adults, while, β-caryophyllene exhibited attracting activity relative to the positive control, DEET. The study revealed that the bioactivity properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components. The results indicate that the essential oil of A. argyi and the isolated compounds have potential to be developed into natural insecticides, fumigants or repellents in controlling insects in stored grains and traditional Chinese medicinal materials.

Wind increases leaf water use efficiency.

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Schymanski, Stanislaus J; Or, Dani

2016-07-01

A widespread perception is that, with increasing wind speed, transpiration from plant leaves increases. However, evidence suggests that increasing wind speed enhances carbon dioxide (CO2 ) uptake while reducing transpiration because of more efficient convective cooling (under high solar radiation loads). We provide theoretical and experimental evidence that leaf water use efficiency (WUE, carbon uptake per water transpired) commonly increases with increasing wind speed, thus improving plants' ability to conserve water during photosynthesis. Our leaf-scale analysis suggests that the observed global decrease in near-surface wind speeds could have reduced WUE at a magnitude similar to the increase in WUE attributed to global rise in atmospheric CO2 concentrations. However, there is indication that the effect of long-term trends in wind speed on leaf gas exchange may be compensated for by the concurrent reduction in mean leaf sizes. These unintuitive feedbacks between wind, leaf size and water use efficiency call for re-evaluation of the role of wind in plant water relations and potential re-interpretation of temporal and geographic trends in leaf sizes. © 2015 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

Relating Stomatal Conductance to Leaf Functional Traits.

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Kröber, Wenzel; Plath, Isa; Heklau, Heike; Bruelheide, Helge

2015-10-12

Leaf functional traits are important because they reflect physiological functions, such as transpiration and carbon assimilation. In particular, morphological leaf traits have the potential to summarize plants strategies in terms of water use efficiency, growth pattern and nutrient use. The leaf economics spectrum (LES) is a recognized framework in functional plant ecology and reflects a gradient of increasing specific leaf area (SLA), leaf nitrogen, phosphorus and cation content, and decreasing leaf dry matter content (LDMC) and carbon nitrogen ratio (CN). The LES describes different strategies ranging from that of short-lived leaves with high photosynthetic capacity per leaf mass to long-lived leaves with low mass-based carbon assimilation rates. However, traits that are not included in the LES might provide additional information on the species' physiology, such as those related to stomatal control. Protocols are presented for a wide range of leaf functional traits, including traits of the LES, but also traits that are independent of the LES. In particular, a new method is introduced that relates the plants' regulatory behavior in stomatal conductance to vapor pressure deficit. The resulting parameters of stomatal regulation can then be compared to the LES and other plant functional traits. The results show that functional leaf traits of the LES were also valid predictors for the parameters of stomatal regulation. For example, leaf carbon concentration was positively related to the vapor pressure deficit (vpd) at the point of inflection and the maximum of the conductance-vpd curve. However, traits that are not included in the LES added information in explaining parameters of stomatal control: the vpd at the point of inflection of the conductance-vpd curve was lower for species with higher stomatal density and higher stomatal index. Overall, stomata and vein traits were more powerful predictors for explaining stomatal regulation than traits used in the LES.

7 CFR 30.31 - Classification of leaf tobacco.

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2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Classification of leaf tobacco. 30.31 Section 30.31... REGULATIONS TOBACCO STOCKS AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.31 Classification of leaf tobacco. For the purpose of this classification leaf tobacco shall...

Biophysical control of leaf temperature

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Dong, N.; Prentice, I. C.; Wright, I. J.

2014-12-01

In principle sunlit leaves can maintain their temperatures within a narrower range than ambient temperatures. This is an important and long-known (but now overlooked) prediction of energy balance theory. Net radiation at leaf surface in steady state (which is reached rapidly) must be equal to the combination of sensible and latent heat exchanges with surrounding air, the former being proportional to leaf-to-air temperature difference (ΔT), the latter to the transpiration rate. We present field measurements of ΔT which confirm the existence of a 'crossover temperature' in the 25-30˚C range for species in a tropical savanna and a tropical rainforest environment. This finding is consistent with a simple representation of transpiration as a function of net radiation and temperature (Priestley-Taylor relationship) assuming an entrainment factor (ω) somewhat greater than the canonical value of 0.26. The fact that leaves in tropical forests are typically cooler than surrounding air, often already by solar noon, is consistent with a recently published comparison of MODIS day-time land-surface temperatures with air temperatures. Theory further predicts a strong dependence of leaf size (which is inversely related to leaf boundary-layer conductance, and therefore to absolute magnitude of ΔT) on moisture availability. Theoretically, leaf size should be determined by either night-time constraints (risk of frost damage to active leaves) or day-time constraints (risk of heat stress damage),with the former likely to predominate - thereby restricting the occurrence of large leaves - at high latitudes. In low latitudes, daytime maximum leaf size is predicted to increase with temperature, provided that water is plentiful. If water is restricted, however, transpiration cannot proceed at the Priestley-Taylor rate, and it quickly becomes advantageous for plants to have small leaves, which do not heat up much above the temperature of their surroundings. The difference between leaf

Possible Roles of Strigolactones during Leaf Senescence

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Yusuke Yamada

2015-09-01

Full Text Available Leaf senescence is a complicated developmental process that involves degenerative changes and nutrient recycling. The progress of leaf senescence is controlled by various environmental cues and plant hormones, including ethylene, jasmonic acid, salicylic acid, abscisic acid, cytokinins, and strigolactones. The production of strigolactones is induced in response to nitrogen and phosphorous deficiency. Strigolactones also accelerate leaf senescence and regulate shoot branching and root architecture. Leaf senescence is actively promoted in a nutrient-poor soil environment, and nutrients are transported from old leaves to young tissues and seeds. Strigolactones might act as important signals in response to nutrient levels in the rhizosphere. In this review, we discuss the possible roles of strigolactones during leaf senescence.

Cotton leaf curl Burewala virus with intact or mutant transcriptional activator proteins: complexity of cotton leaf curl disease.

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Kumar, Jitendra; Gunapati, Samatha; Alok, Anshu; Lalit, Adarsh; Gadre, Rekha; Sharma, Naresh C; Roy, Joy K; Singh, Sudhir P

2015-05-01

Cotton leaf curl disease (CLCuD) is a serious disease of cotton on the Indian subcontinent. In the present study, three cotton leaf curl viruses, cotton leaf curl Burewala virus (CLCuBuV), cotton leaf curl Kokhran virus (CLCuKoV) and cotton leaf curl Multan virus (CLCuMV), and their associated satellites, cotton leaf curl Multan betasatellite (CLCuMB) and cotton leaf curl Multan alphasatellite (CLCuMA), were detected. CLCuBuV with either intact (CLCuBuV-1) or mutant (CLCuBuV-2) transcriptional activator protein (TrAP) were detected in different plants. Agroinoculation with CLCuBuV-1 or CLCuBuV-2 together with CLCuMB and CLCuMA, resulted in typical leaf curling and stunting of tobacco plants. Inoculation with CLCuKoV or an isolate of CLCuMV (CLCuMV-2), together with CLCuMB and CLCuMA, induced severe leaf curling, while the other isolate of CLCuMV (CLCuMV-1), which was recombinant in origin, showed mild leaf curling in tobacco. To investigate the effect of intact or mutant TrAP and also the recombination events, CLCuBuV-1, CLCuBuV-2, CLCuMV-1 or CLCuMV-2 together with the satellites (CLCuMA and CLCuMB) were transferred to cotton via whitefly-mediated transmission. Cotton plants containing CLCuBuV-1, CLCuBuV-2 or CLCuMV-2 together with satellites showed curling and stunting, whereas the plants having CLCuMV-1 and the satellites showed only mild and indistinguishable symptoms. CLCuBuV-1 (intact TrAP) showed severe symptoms in comparison to CLCuBuV-2 (mutant TrAP). The present study reveals that two types of CLCuBuV, one with an intact TrAP and the other with a mutant TrAP, exist in natural infection of cotton in India. Additionally, CLCuMuV-1, which has a recombinant origin, induces mild symptoms in comparison to the other CLCuMV isolates.

Effects of Artemisia lanata Extract on Reproductive Parameters of Female Rats

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Ainehchi Nava

2014-04-01

Full Text Available Objective: Until date, there is no report on safety of Artemisia lanata. This study aimed to determine the possible undesirable effects of A. lanata on reproduction of female rats. Materials and Methods: The pregnant rats were treated (i.p. with vehicle or 200 and 400mg/kg of A. lanata hydroalcoholic extract from the 2-8 day of pregnancy. Then, number and weight of neonates, duration of pregnancy, and percent of dead fetuses were determined. Furthermore, cytotoxicity of this plant was tested using fibroblast (L929 and Chinese hamster ovary (Cho cell lines. Results: The A. lanata had no significant effect on duration of pregnancy, average number of neonates, and weight of neonates. However, administration of 200 and 400 mg/kg of the extract led to 30 and 44% abortion in animals, respectively. The extract at concentrations ≥ 200 μg/ml significantly (P < 0.001 inhibited the proliferation of L929 fibroblast cells. Regarding the Cho cells, the extract induced toxicity only at concentration of 800 μg/ml (P < 0.010. Conclusion: Our results showed that continuous consumption of A. lanata in pregnancy may increase the risk of abortion and also may have toxic effect on some cells.

Control of Three Stored−Product Beetles with Artemisia haussknechtii (Boiss (Asteraceae Essential Oil

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Seyed Mehdi Hashemi

2012-12-01

Full Text Available Fumigant toxicity of the essential oil of aerial parts from Artemisia haussknechtii (Boiss (Asteraceae was investigated against the cowpea weevil Callosobruchus maculatus (Fab., the rice weevil Sitophilus oryzae (L., and the red flour beetle Tribolium castaneum (Herbst. Dry ground plants were subjected to hydro−distillation using a Clevenger−type apparatus and the chemical composition of the volatile oil was studied by gas chromatography−mass spectrometry (GC−MS. The major components of the oil were camphor (29.24%, 1, 8−cineol (27.62%, yomogi alcohol (5.23%, and camphene (4.80%. The essential oil in same concentrations was assayed against (1−7 days old adults of insect species and percentage mortality was recorded after 24, 48, and 72 h exposure times. LC50 values were varied between 19.84 and 103.59 μL L-1 air, depending on insect species and exposure time. Callosobruchus maculatus was more susceptible than other species. These results suggested that A. haussknechtii oil might have potential as a control agent against C. maculatus, S. oryzae and T. castaneum.

The plant leaf movement analyzer (PALMA): a simple tool for the analysis of periodic cotyledon and leaf movement in Arabidopsis thaliana.

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Wagner, Lucas; Schmal, Christoph; Staiger, Dorothee; Danisman, Selahattin

2017-01-01

The analysis of circadian leaf movement rhythms is a simple yet effective method to study effects of treatments or gene mutations on the circadian clock of plants. Currently, leaf movements are analysed using time lapse photography and subsequent bioinformatics analyses of leaf movements. Programs that are used for this purpose either are able to perform one function (i.e. leaf tip detection or rhythm analysis) or their function is limited to specific computational environments. We developed a leaf movement analysis tool-PALMA-that works in command line and combines image extraction with rhythm analysis using Fast Fourier transformation and non-linear least squares fitting. We validated PALMA in both simulated time series and in experiments using the known short period mutant sensitivity to red light reduced 1 ( srr1 - 1 ). We compared PALMA with two established leaf movement analysis tools and found it to perform equally well. Finally, we tested the effect of reduced iron conditions on the leaf movement rhythms of wild type plants. Here, we found that PALMA successfully detected period lengthening under reduced iron conditions. PALMA correctly estimated the period of both simulated and real-life leaf movement experiments. As a platform-independent console-program that unites both functions needed for the analysis of circadian leaf movements it is a valid alternative to existing leaf movement analysis tools.

Effects of nitrogen application rate and leaf age on the distribution pattern of leaf SPAD readings in the rice canopy.

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Hu Yang

Full Text Available A Soil-Plant Analysis Development (SPAD chlorophyll meter can be used as a simple tool for evaluating N concentration of the leaf and investigating the combined effects of nitrogen rate and leaf age on N distribution. We conducted experiments in a paddy field over two consecutive years (2008-2009 using rice plants treated with six different N application levels. N distribution pattern was determined by SPAD readings based on the temporal dynamics of N concentrations in individual leaves. At 62 days after transplantation (DAT in 2008 and DAT 60 in 2009, leaf SPAD readings increased from the upper to lower in the rice canopy that received N levels of 150 to 375 kg ha(-1The differences in SPAD readings between the upper and lower leaf were larger under higher N application rates. However, as plants grew, this atypical distribution of SPAD readings in canopy leaf quickly reversed to the general order. In addition, temporal dynamics of the leaf SPAD readings (N concentrations were fitted to a piecewise function. In our model, changes in leaf SPAD readings were divided into three stages: growth, functioning, and senescence periods. The leaf growth period lasted approximately 6 days, and cumulative growing days were not affected by N application rates. The leaf functioning period was represented with a relatively stable SPAD reading related to N application rate, and cumulative growing days were extended with increasing N application rates. A quadratic equation was utilized to describe the relationship between SPAD readings and leaf age during the leaf senescence period. The rate of decrease in SPAD readings increased with the age of leaves, but the rate was slowed by N application. As leaves in the lower canopy were physiologically older than leaves in the upper canopy, the rate of decrease in SPAD readings was faster in the lower leaves.

Effect of Artemisia absinthium essential oil on antioxidative systems of broiler's liver

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Kostadinović Ljiljana M.

2014-01-01

Full Text Available The effect of Artemisia absinthium essential oil (AAEO on enzymatic activity of super-oxide-dismutase (SOD, glutathione-peroxidase (GSHPx, glutathione-reductase (GR, peroxidase (POD, xantine-oxidase (XOD and non-enzymatic (content of lipid peroxides (LPx and gluthathione (GSH antioxidative status of broilers infected with mixture of oocysts of Eimeria tenella, Eimeria mitis and Eimeria necatrix in comparison to coccidiostat salinomycin was investigated. The in vivo investigation were carried out on 120 Arbor acres broilers of both sexes. Broilers were randomly distributed into four groups. Group A was uninfected and untreated; group B was infected and was kept untreated; group C preventively received coccidiostatic salinomycin in quantity of 60 mg/kg of feed and was inoculated with coccidia species at 21st day-of-age and group D received in feed AAEO in quantity of 3 g/kg and was infected with Eimeria oocysts at 21st day-of-age. Livers were collected for the subsequent evaluation of antioxidative status. It was concluded that AAEO added in feed for broilers prevented the development of coccidia oocysts and therefore it can be used as prophylactic feed additive.

A hairy-leaf gene, BLANKET LEAF, of wild Oryza nivara increases photosynthetic water use efficiency in rice.

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Hamaoka, Norimitsu; Yasui, Hideshi; Yamagata, Yoshiyuki; Inoue, Yoko; Furuya, Naruto; Araki, Takuya; Ueno, Osamu; Yoshimura, Atsushi

2017-12-01

High water use efficiency is essential to water-saving cropping. Morphological traits that affect photosynthetic water use efficiency are not well known. We examined whether leaf hairiness improves photosynthetic water use efficiency in rice. A chromosome segment introgression line (IL-hairy) of wild Oryza nivara (Acc. IRGC105715) with the genetic background of Oryza sativa cultivar 'IR24' had high leaf pubescence (hair). The leaf hairs developed along small vascular bundles. Linkage analysis in BC 5 F 2 and F 3 populations showed that the trait was governed by a single gene, designated BLANKET LEAF (BKL), on chromosome 6. IL-hairy plants had a warmer leaf surface in sunlight, probably due to increased boundary layer resistance. They had a lower transpiration rate under moderate and high light intensities, resulting in higher photosynthetic water use efficiency. Introgression of BKL on chromosome 6 from O. nivara improved photosynthetic water use efficiency in the genetic background of IR24.

Seasonal patterns of leaf gas exchange and water relations in dry rain forest trees of contrasting leaf phenology.

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Choat, Brendan; Ball, Marilyn C; Luly, Jon G; Donnelly, Christine F; Holtum, Joseph A M

2006-05-01

Diurnal and seasonal patterns of leaf gas exchange and water relations were examined in tree species of contrasting leaf phenology growing in a seasonally dry tropical rain forest in north-eastern Australia. Two drought-deciduous species, Brachychiton australis (Schott and Endl.) A. Terracc. and Cochlospermum gillivraei Benth., and two evergreen species, Alphitonia excelsa (Fenzal) Benth. and Austromyrtus bidwillii (Benth.) Burret. were studied. The deciduous species had higher specific leaf areas and maximum photosynthetic rates per leaf dry mass in the wet season than the evergreens. During the transition from wet season to dry season, total canopy area was reduced by 70-90% in the deciduous species and stomatal conductance (g(s)) and assimilation rate (A) were markedly lower in the remaining leaves. Deciduous species maintained daytime leaf water potentials (Psi(L)) at close to or above wet season values by a combination of stomatal regulation and reduction in leaf area. Thus, the timing of leaf drop in deciduous species was not associated with large negative values of daytime Psi(L) (greater than -1.6 MPa) or predawn Psi(L) (greater than -1.0 MPa). The deciduous species appeared sensitive to small perturbations in soil and leaf water status that signalled the onset of drought. The evergreen species were less sensitive to the onset of drought and g(s) values were not significantly lower during the transitional period. In the dry season, the evergreen species maintained their canopies despite increasing water-stress; however, unlike Eucalyptus species from northern Australian savannas, A and g(s) were significantly lower than wet season values.

Leaf area index from litter collection: impact of specific leaf area variability within a beech stand

Energy Technology Data Exchange (ETDEWEB)

Bouriaud, O. [Inst. National de la Recherche Agronomique, Centre de Recherches Forestieres de Nancy, Champenoux (France); Soudani, K. [Univ. Paris-Sud XI, Dept. d' Ecophysiologie Vegetale, Lab. Ecologie Systematique et Evolution, Orsay Cedex (France); Breda, N. [Inst. National de la Recherche Agronomique, Centre de Recherches Forestieres de Nancy, Champenoux (France)

2003-06-01

Litter fall collection is a direct method widely used to estimate leaf area index (LAI) in broad-leaved forest stands. Indirect measurements using radiation transmittance and gap fraction theory are often compared and calibrated against litter fall, which is considered as a reference method, but few studies address the question of litter specific leaf area (SLA) measurement and variability. SLA (leaf area per unit of dry weight, m{sup 2}{center_dot}g{sup -1}) is used to convert dry leaf litter biomass (g .m{sup -}2) into leaf area per ground unit area (m{sup 2}{center_dot}m{sup -2}). We paid special attention to this parameter in two young beech stands (dense and thinned) in northeastern France. The variability of both canopy (closure, LAI) and site conditions (soil properties, vegetation) was investigated as potential contributing factors to beech SLA variability. A systematic description of soil and floristic composition was performed and three types of soil were identified. Ellenberg's indicator values were averaged for each plot to assess nitrogen soil content. SLA of beech litter was measured three times during the fall in 23 plots in the stands (40 ha). Litter was collected bimonthly in square-shaped traps (0.5 m{sup 2}) and dried. Before drying, 30 leaves per plot and for each date were sampled, and leaf length, width, and area were measured with the help of a LI-COR areameter. SLA was calculated as the ratio of cumulated leaf area to total dry weight of the 30 leaves. Leaves characteristics per plot were averaged for the three dates of litter collection. Plant area index (PAI), estimated using the LAI-2000 plant canopy analyser and considering only the upper three rings, ranged from 2.9 to 8.1. Specific leaf area of beech litter was also highly different from one plot to the other, ranging from 150 to 320 cm{sup 2}{center_dot}g{sup -1}. Nevertheless, no relationship was found between SLA and stand canopy closure or PAI On the contrary, a significant

Leaf area index from litter collection: impact of specific leaf area variability within a beech stand

International Nuclear Information System (INIS)

Bouriaud, O.; Soudani, K.; Breda, N.

2003-01-01

Litter fall collection is a direct method widely used to estimate leaf area index (LAI) in broad-leaved forest stands. Indirect measurements using radiation transmittance and gap fraction theory are often compared and calibrated against litter fall, which is considered as a reference method, but few studies address the question of litter specific leaf area (SLA) measurement and variability. SLA (leaf area per unit of dry weight, m 2 ·g -1 ) is used to convert dry leaf litter biomass (g .m - 2) into leaf area per ground unit area (m 2 ·m -2 ). We paid special attention to this parameter in two young beech stands (dense and thinned) in northeastern France. The variability of both canopy (closure, LAI) and site conditions (soil properties, vegetation) was investigated as potential contributing factors to beech SLA variability. A systematic description of soil and floristic composition was performed and three types of soil were identified. Ellenberg's indicator values were averaged for each plot to assess nitrogen soil content. SLA of beech litter was measured three times during the fall in 23 plots in the stands (40 ha). Litter was collected bimonthly in square-shaped traps (0.5 m 2 ) and dried. Before drying, 30 leaves per plot and for each date were sampled, and leaf length, width, and area were measured with the help of a LI-COR areameter. SLA was calculated as the ratio of cumulated leaf area to total dry weight of the 30 leaves. Leaves characteristics per plot were averaged for the three dates of litter collection. Plant area index (PAI), estimated using the LAI-2000 plant canopy analyser and considering only the upper three rings, ranged from 2.9 to 8.1. Specific leaf area of beech litter was also highly different from one plot to the other, ranging from 150 to 320 cm 2 ·g -1 . Nevertheless, no relationship was found between SLA and stand canopy closure or PAI On the contrary, a significant relationship between SLA and soil properties was observed. Both SLA

Effect of nitrogen supply on leaf growth, leaf nitrogen economy and photosynthetic capacity in potato

NARCIS (Netherlands)

Vos, J.; Putten, van der P.E.L.

1998-01-01

Literature reports show little effect of nitrogen supply on radiation use efficiency in potato and in other dicotyledonous C3 species. This paper tests the hypothesis that potato reduces leaf size rather than leaf nitrogen concentration and photosynthetic capacity when nitrogen is in short supply.

Leaf extraction and analysis framework graphical user interface: segmenting and analyzing the structure of leaf veins and areoles.

Science.gov (United States)

Price, Charles A; Symonova, Olga; Mileyko, Yuriy; Hilley, Troy; Weitz, Joshua S

2011-01-01

Interest in the structure and function of physical biological networks has spurred the development of a number of theoretical models that predict optimal network structures across a broad array of taxonomic groups, from mammals to plants. In many cases, direct tests of predicted network structure are impossible given the lack of suitable empirical methods to quantify physical network geometry with sufficient scope and resolution. There is a long history of empirical methods to quantify the network structure of plants, from roots, to xylem networks in shoots and within leaves. However, with few exceptions, current methods emphasize the analysis of portions of, rather than entire networks. Here, we introduce the Leaf Extraction and Analysis Framework Graphical User Interface (LEAF GUI), a user-assisted software tool that facilitates improved empirical understanding of leaf network structure. LEAF GUI takes images of leaves where veins have been enhanced relative to the background, and following a series of interactive thresholding and cleaning steps, returns a suite of statistics and information on the structure of leaf venation networks and areoles. Metrics include the dimensions, position, and connectivity of all network veins, and the dimensions, shape, and position of the areoles they surround. Available for free download, the LEAF GUI software promises to facilitate improved understanding of the adaptive and ecological significance of leaf vein network structure.

Leaf Area Estimation Models for Ginger ( Zingibere officinale Rosc ...

African Journals Online (AJOL)

The study was carried out to develop leaf area estimation models for three cultivars (37/79, 38/79 and 180/73) and four accessions (29/86, 30/86, 47/86 and 52/86) of ginger. Significant variations were observed among the tested genotypes in leaf length (L), leaf width (W) and actual leaf area (ALA). Leaf area was highly ...

A Global Data Set of Leaf Photosynthetic Rates, Leaf N and P, and Specific Leaf Area

Data.gov (United States)

National Aeronautics and Space Administration — ABSTRACT: This global data set of photosynthetic rates and leaf nutrient traits was compiled from a comprehensive literature review. It includes estimates of Vcmax...

A Global Data Set of Leaf Photosynthetic Rates, Leaf N and P, and Specific Leaf Area

Data.gov (United States)

National Aeronautics and Space Administration — This global data set of photosynthetic rates and leaf nutrient traits was compiled from a comprehensive literature review. It includes estimates of Vcmax (maximum...

Does investment in leaf defenses drive changes in leaf economic strategy? A focus on whole-plant ontogeny.

Science.gov (United States)

Mason, Chase M; Donovan, Lisa A

2015-04-01

Leaf defenses have long been studied in the context of plant growth rate, resource availability, and optimal investment theory. Likewise, one of the central modern paradigms of plant ecophysiology, the leaf economics spectrum (LES), has been extensively studied in the context of these factors across ecological scales ranging from global species data sets to temporal shifts within individuals. Despite strong physiological links between LES strategy and leaf defenses in structure, function, and resource investment, the relationship between these trait classes has not been well explored. This study investigates the relationship between leaf defenses and LES strategy across whole-plant ontogeny in three diverse Helianthus species known to exhibit dramatic ontogenetic shifts in LES strategy, focusing primarily on physical and quantitative chemical defenses. Plants were grown under controlled environmental conditions and sampled for LES and defense traits at four ontogenetic stages. Defenses were found to shift strongly with ontogeny, and to correlate strongly with LES strategy. More advanced ontogenetic stages with more conservative LES strategy leaves had higher tannin activity and toughness in all species, and higher leaf dry matter content in two of three species. Modeling results in two species support the conclusion that changes in defenses drive changes in LES strategy through ontogeny, and in one species that changes in defenses and LES strategy are likely independently driven by ontogeny. Results of this study support the hypothesis that leaf-level allocation to defenses might be an important determinant of leaf economic traits, where high investment in defenses drives a conservative LES strategy.

Spectrophotometry of Artemisia tridentata to quantitatively determine subspecies

Science.gov (United States)

Richardson, Bryce; Boyd, Alicia; Tobiasson, Tanner; Germino, Matthew

2018-01-01

Ecological restoration is predicated on our abilities to discern plant taxa. Taxonomic identification is a first step in ensuring that plants are appropriately adapted to the site. An example of the need to identify taxonomic differences comes from big sagebrush (Artemisia tridentata). This species is composed of three predominant subspecies occupying distinct environmental niches, but overlap and hybridization are common in ecotones. Restoration of A. tridentata largely occurs using wildland collected seed, but there is uncertainty in the identification of subspecies or mix of subspecies from seed collections. Laboratory techniques that can determine subspecies composition would be desirable to ensure that subspecies match the restoration site environment. In this study, we use spectrophotometry to quantify chemical differences in the water-soluble compound, coumarin. Ultraviolet (UV) absorbance of A. tridentata subsp. vaseyana showed distinct differences among A.t. tridentata and wyomingensis. No UV absorbance differences were detected between A.t. tridentata and wyomingensis. Analyses of samples from > 600 plants growing in two common gardens showed that UV absorbance was unaffected by environment. Moreover, plant tissues (leaves and seed chaff) explained only a small amount of the variance. UV fluorescence of water-eluted plant tissue has been used for many years to indicate A.t. vaseyana; however, interpretation has been subjective. Use of spectrophotometry to acquire UV absorbance provides empirical results that can be used in seed testing laboratories using the seed chaff present with the seed to certify A. tridentata subspecies composition. On the basis of our methods, UV absorbance values 3.1 would indicate either A.t. tridentata or wyomingensis. UV absorbance values between 2.7 and 3.1 would indicate a mixture of A.t. vaseyana and the other two subspecies.

Natural regeneration processes in big sagebrush (Artemisia tridentata)

Science.gov (United States)

Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

2014-01-01

Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified and characterized the controls of big sagebrush seed production, germination, and establishment. The largest knowledge gaps and associated research needs include quiescence and dormancy of embryos and seedlings; variation in seed production and germination percentages; wet-thermal time model of germination; responses to frost events (including freezing/thawing of soils), CO2 concentration, and nutrients in combination with water availability; suitability of microsite vs. site conditions; competitive ability as well as seedling growth responses; and differences among subspecies and ecoregions. Potential impacts of climate change on big sagebrush regeneration could include that temperature increases may not have a large direct influence on regeneration due to the broad temperature optimum for regeneration, whereas indirect effects could include selection for populations with less stringent seed dormancy. Drier conditions will have direct negative effects on germination and seedling survival and could also lead to lighter seeds, which lowers germination success further. The short seed dispersal distance of big sagebrush may limit its tracking of suitable climate; whereas, the low competitive ability of big sagebrush seedlings may limit successful competition with species that track climate. An improved understanding of the

Influence of Vegetation Structure on Lidar-derived Canopy Height and Fractional Cover in Forested Riparian Buffers During Leaf-Off and Leaf-On Conditions

Science.gov (United States)

Wasser, Leah; Day, Rick; Chasmer, Laura; Taylor, Alan

2013-01-01

Estimates of canopy height (H) and fractional canopy cover (FC) derived from lidar data collected during leaf-on and leaf-off conditions are compared with field measurements from 80 forested riparian buffer plots. The purpose is to determine if existing lidar data flown in leaf-off conditions for applications such as terrain mapping can effectively estimate forested riparian buffer H and FC within a range of riparian vegetation types. Results illustrate that: 1) leaf-off and leaf-on lidar percentile estimates are similar to measured heights in all plots except those dominated by deciduous compound-leaved trees where lidar underestimates H during leaf off periods; 2) canopy height models (CHMs) underestimate H by a larger margin compared to percentile methods and are influenced by vegetation type (conifer needle, deciduous simple leaf or deciduous compound leaf) and canopy height variability, 3) lidar estimates of FC are within 10% of plot measurements during leaf-on periods, but are underestimated during leaf-off periods except in mixed and conifer plots; and 4) depth of laser pulse penetration lower in the canopy is more variable compared to top of the canopy penetration which may influence within canopy vegetation structure estimates. This study demonstrates that leaf-off lidar data can be used to estimate forested riparian buffer canopy height within diverse vegetation conditions and fractional canopy cover within mixed and conifer forests when leaf-on lidar data are not available. PMID:23382966

Leaf structural characteristics are less important than leaf chemical properties in determining the response of leaf mass per area and photosynthesis of Eucalyptus saligna to industrial-age changes in [CO2] and temperature.

Science.gov (United States)

Xu, Cheng-Yuan; Salih, Anya; Ghannoum, Oula; Tissue, David T

2012-10-01

The rise in atmospheric [CO(2)] is associated with increasing air temperature. However, studies on plant responses to interactive effects of [CO(2)] and temperature are limited, particularly for leaf structural attributes. In this study, Eucalyptus saligna plants were grown in sun-lit glasshouses differing in [CO(2)] (290, 400, and 650 µmol mol(-1)) and temperature (26 °C and 30 °C). Leaf anatomy and chloroplast parameters were assessed with three-dimensional confocal microscopy, and the interactive effects of [CO(2)] and temperature were quantified. The relative influence of leaf structural attributes and chemical properties on the variation of leaf mass per area (LMA) and photosynthesis within these climate regimes was also determined. Leaf thickness and mesophyll size increased in higher [CO(2)] but decreased at the warmer temperature; no treatment interaction was observed. In pre-industrial [CO(2)], warming reduced chloroplast diameter without altering chloroplast number per cell, but the opposite pattern (reduced chloroplast number per cell and unchanged chloroplast diameter) was observed in both current and projected [CO(2)]. The variation of LMA was primarily explained by total non-structural carbohydrate (TNC) concentration rather than leaf thickness. Leaf photosynthetic capacity (light- and [CO(2)]-saturated rate at 28 °C) and light-saturated photosynthesis (under growth [CO(2)] and temperature) were primarily determined by leaf nitrogen contents, while secondarily affected by chloroplast gas exchange surface area and chloroplast number per cell, respectively. In conclusion, leaf structural attributes are less important than TNC and nitrogen in affecting LMA and photosynthesis responses to the studied climate regimes, indicating that leaf structural attributes have limited capacity to adjust these functional traits in a changing climate.

Composition of the essential oils from Rocky Mountain juniper (Juniperus scopulorum), Big sagebrush (Artemisia tridentata), and White Sage (Salvia apiana).

Energy Technology Data Exchange (ETDEWEB)

Hochrein, James Michael; Irwin, Adriane Nadine; Borek, Theodore Thaddeus III

2003-09-01

The essential oils of Juniperus scopulorum, Artemisia tridentata, and Salvia apiana obtained by steam extraction were analyzed by GC-MS and GC-FID. For J. scopulorum, twenty-five compounds were identified which accounts for 92.43% of the oil. The primary constituents were sabinene (49.91%), {alpha}-terpinene (9.95%), and 4-terpineol (6.79%). For A. tridentata, twenty compounds were identified which accounts for 84.32% of the oil. The primary constituents were camphor (28.63%), camphene (16.88%), and 1,8-cineole (13.23%). For S. apiana, fourteen compounds were identified which accounts for 96.76% of the oil. The primary component was 1,8-cineole (60.65%).

Dependence of fluence errors in dynamic IMRT on leaf-positional errors varying with time and leaf number

International Nuclear Information System (INIS)

Zygmanski, Piotr; Kung, Jong H.; Jiang, Steve B.; Chin, Lee

2003-01-01

In d-MLC based IMRT, leaves move along a trajectory that lies within a user-defined tolerance (TOL) about the ideal trajectory specified in a d-MLC sequence file. The MLC controller measures leaf positions multiple times per second and corrects them if they deviate from ideal positions by a value greater than TOL. The magnitude of leaf-positional errors resulting from finite mechanical precision depends on the performance of the MLC motors executing leaf motions and is generally larger if leaves are forced to move at higher speeds. The maximum value of leaf-positional errors can be limited by decreasing TOL. However, due to the inherent time delay in the MLC controller, this may not happen at all times. Furthermore, decreasing the leaf tolerance results in a larger number of beam hold-offs, which, in turn leads, to a longer delivery time and, paradoxically, to higher chances of leaf-positional errors (≤TOL). On the other end, the magnitude of leaf-positional errors depends on the complexity of the fluence map to be delivered. Recently, it has been shown that it is possible to determine the actual distribution of leaf-positional errors either by the imaging of moving MLC apertures with a digital imager or by analysis of a MLC log file saved by a MLC controller. This leads next to an important question: What is the relation between the distribution of leaf-positional errors and fluence errors. In this work, we introduce an analytical method to determine this relation in dynamic IMRT delivery. We model MLC errors as Random-Leaf Positional (RLP) errors described by a truncated normal distribution defined by two characteristic parameters: a standard deviation σ and a cut-off value Δx 0 (Δx 0 ∼TOL). We quantify fluence errors for two cases: (i) Δx 0 >>σ (unrestricted normal distribution) and (ii) Δx 0 0 --limited normal distribution). We show that an average fluence error of an IMRT field is proportional to (i) σ/ALPO and (ii) Δx 0 /ALPO, respectively, where

The Nissan LEAF electric powertrain

Energy Technology Data Exchange (ETDEWEB)

Nakazawa, Shinsuke [Nissan Motor Co., Ltd. (Japan)

2011-07-01

The need for CO{sub 2} reduction as a countermeasure to global warming, and to move away from our dependence on fossil fuels as a countermeasure to energy security are urgent issues. One of the ultimate goals to achieving these targets is to develop a 'Zero emission car' such as an electric vehicle or a fuel cell vehicle, along with the manufacturing of clean energy. Nissan have developed a new powertrain for the electric vehicle, and have installed it in the Nissan LEAF. Sales of the Nissan LEAF started in North America, Europe and Japan in 2010, with plans to sell it globally by 2012. In order to achieve an improved driving range, power performance and drivability performance, Nissan have adapted a high efficiency synchronous motor, a water-cooled inverter, and reducer. Moreover, the Nissan LEAF has the capability of a 3.3kW AC charge and a 50kW DC quick charge. This presentation will introduce the features of the electric powertrain adopted for Nissan LEAF. (orig.)

A non-destructive method for estimating onion leaf area

Directory of Open Access Journals (Sweden)

Córcoles J.I.

2015-06-01

Full Text Available Leaf area is one of the most important parameters for characterizing crop growth and development, and its measurement is useful for examining the effects of agronomic management on crop production. It is related to interception of radiation, photosynthesis, biomass accumulation, transpiration and gas exchange in crop canopies. Several direct and indirect methods have been developed for determining leaf area. The aim of this study is to develop an indirect method, based on the use of a mathematical model, to compute leaf area in an onion crop using non-destructive measurements with the condition that the model must be practical and useful as a Decision Support System tool to improve crop management. A field experiment was conducted in a 4.75 ha commercial onion plot irrigated with a centre pivot system in Aguas Nuevas (Albacete, Spain, during the 2010 irrigation season. To determine onion crop leaf area in the laboratory, the crop was sampled on four occasions between 15 June and 15 September. At each sampling event, eight experimental plots of 1 m2 were used and the leaf area for individual leaves was computed using two indirect methods, one based on the use of an automated infrared imaging system, LI-COR-3100C, and the other using a digital scanner EPSON GT-8000, obtaining several images that were processed using Image J v 1.43 software. A total of 1146 leaves were used. Before measuring the leaf area, 25 parameters related to leaf length and width were determined for each leaf. The combined application of principal components analysis and cluster analysis for grouping leaf parameters was used to reduce the number of variables from 25 to 12. The parameter derived from the product of the total leaf length (L and the leaf diameter at a distance of 25% of the total leaf length (A25 gave the best results for estimating leaf area using a simple linear regression model. The model obtained was useful for computing leaf area using a non

Modeling canopy-level productivity: is the "big-leaf" simplification acceptable?

Science.gov (United States)

Sprintsin, M.; Chen, J. M.

2009-05-01

The "big-leaf" approach to calculating the carbon balance of plant canopies assumes that canopy carbon fluxes have the same relative responses to the environment as any single unshaded leaf in the upper canopy. Widely used light use efficiency models are essentially simplified versions of the big-leaf model. Despite its wide acceptance, subsequent developments in the modeling of leaf photosynthesis and measurements of canopy physiology have brought into question the assumptions behind this approach showing that big leaf approximation is inadequate for simulating canopy photosynthesis because of the additional leaf internal control on carbon assimilation and because of the non-linear response of photosynthesis on leaf nitrogen and absorbed light, and changes in leaf microenvironment with canopy depth. To avoid this problem a sunlit/shaded leaf separation approach, within which the vegetation is treated as two big leaves under different illumination conditions, is gradually replacing the "big-leaf" strategy, for applications at local and regional scales. Such separation is now widely accepted as a more accurate and physiologically based approach for modeling canopy photosynthesis. Here we compare both strategies for Gross Primary Production (GPP) modeling using the Boreal Ecosystem Productivity Simulator (BEPS) at local (tower footprint) scale for different land cover types spread over North America: two broadleaf forests (Harvard, Massachusetts and Missouri Ozark, Missouri); two coniferous forests (Howland, Maine and Old Black Spruce, Saskatchewan); Lost Creek shrubland site (Wisconsin) and Mer Bleue petland (Ontario). BEPS calculates carbon fixation by scaling Farquhar's leaf biochemical model up to canopy level with stomatal conductance estimated by a modified version of the Ball-Woodrow-Berry model. The "big-leaf" approach was parameterized using derived leaf level parameters scaled up to canopy level by means of Leaf Area Index. The influence of sunlit

Ethanolic extract of Artemisia aucheri induces regression of aorta wall fatty streaks in hypercholesterolemic rabbits.

Science.gov (United States)

Asgary, S; Dinani, N Jafari; Madani, H; Mahzouni, P

2008-05-01

Artemisia aucheri is a native-growing plant which is widely used in Iranian traditional medicine. This study was designed to evaluate the effects of A. aucheri on regression of atherosclerosis in hypercholesterolemic rabbits. Twenty five rabbits were randomly divided into five groups of five each and treated 3-months as follows: 1: normal diet, 2: hypercholesterolemic diet (HCD), 3 and 4: HCD for 60 days and then normal diet and normal diet + A. aucheri (100 mg x kg(-1) x day(-1)) respectively for an additional 30 days (regression period). In the regression period dietary use of A. aucheri in group 4 significantly decreased total cholesterol, triglyceride and LDL-cholesterol, while HDL-cholesterol was significantly increased. The atherosclerotic area was significantly decreased in this group. Animals, which received only normal diet in the regression period showed no regression but rather progression of atherosclerosis. These findings suggest that A. aucheri may cause regression of atherosclerotic lesions.

Baby leaf lettuce germplasm enhancement: developing diverse populations with resistance to bacterial leaf spot caused by Xanthomonas campestris pv. vitians

Science.gov (United States)

Baby leaf lettuce cultivars with resistance to bacterial leaf spot (BLS) caused by Xanthomonas campestris pv. vitians (Xcv) are needed to reduce crop losses. The objectives of this research were to assess the genetic diversity for BLS resistance in baby leaf lettuce cultivars and to select early gen...

Leaf turgor loss point is correlated with drought tolerance and leaf carbon economics traits.

Science.gov (United States)

Zhu, Shi-Dan; Chen, Ya-Jun; Ye, Qing; He, Peng-Cheng; Liu, Hui; Li, Rong-Hua; Fu, Pei-Li; Jiang, Guo-Feng; Cao, Kun-Fang

2018-05-01

Leaf turgor loss point (πtlp) indicates the capacity of a plant to maintain cell turgor pressure during dehydration, which has been proven to be strongly predictive of the plant response to drought. In this study, we compiled a data set of πtlp for 1752 woody plant individuals belonging to 389 species from nine major woody biomes in China, along with reduced sample size of hydraulic and leaf carbon economics data. We aimed to investigate the variation of πtlp across biomes varying in water availability. We also tested two hypotheses: (i) πtlp predicts leaf hydraulic safety margins and (ii) it is correlated with leaf carbon economics traits. Our results showed that there was a positive relationship between πtlp and aridity index: biomes from humid regions had less negative values than those from arid regions. This supports the idea that πtlp may reflect drought tolerance at the scale of woody biomes. As expected, πtlp was significantly positively correlated with leaf hydraulic safety margins that varied significantly across biomes, indicating that this trait may be useful in modelling changes of forest components in response to increasing drought. Moreover, πtlp was correlated with a suite of coordinated hydraulic and economics traits; therefore, it can be used to predict the position of a given species along the 'fast-slow' whole-plant economics spectrum. This study expands our understanding of the biological significance of πtlp not only in drought tolerance, but also in the plant economics spectrum.

7 CFR 29.3528 - Leaf surface.

Science.gov (United States)

2010-01-01

... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3528 Leaf surface. The roughness or smoothness of the web or lamina of a tobacco leaf...

Flavonoids casticin and chrysosplenol D from Artemisia annua L. inhibit inflammation in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Li, Yu-Jie; Guo, Yan; Yang, Qing; Weng, Xiao-Gang; Yang, Lan; Wang, Ya-Jie; Chen, Ying; Zhang, Dong; Li, Qi; Liu, Xu-Cen; Kan, Xiao-Xi; Chen, Xi [Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700 (China); Zhu, Xiao-Xin, E-mail: zhuxx59@163.com [Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700 (China); Kmoníèková, Eva [Institute of Pharmacology and Toxicology, Faculty of Medicine in Pilsen, Charles University, Pilsen (Czech Republic); Zídek, Zdenìk [Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeòská 1083, 142 20 Prague (Czech Republic)

2015-08-01

Background: The aim of our experiments was to investigate the anti-inflammatory properties of casticin and chrysosplenol D, two flavonoids present in Artemisia annua L. Methods: Topical inflammation was induced in ICR mice using croton oil. Mice were then treated with casticin or chrysosplenol D. Cutaneous histological changes and edema were assessed. ICR mice were intragastrically administrated with casticin or chrysosplenol D followed by intraperitoneal injection of lipopolysaccharide (LPS). Mouse Raw264.7 macrophage cells were incubated with casticin or chrysosplenol D. Intracellular phosphorylation was detected, and migration was assessed by trans-well assay. HT-29/NFκB-luc cells were incubated with casticin or chrysosplenol D in the presence or absence of LPS, and NF-κB activation was quantified. Results: In mice, administration of casticin (0.5, 1 and 1.5 μmol/cm{sup 2}) and chrysosplenol D (1 and 1.5 μmol/cm{sup 2}) inhibited croton oil-induced ear edema (casticin: 29.39–64.95%; chrysosplenol D: 37.76–65.89%, all P < 0.05) in a manner similar to indomethacin (0.5, 1 and 1.5 μmol/cm{sup 2}; 55.63–84.58%). Casticin (0.07, 0.13 and 0.27 mmol/kg) and chrysosplenol D (0.07, 0.14 and 0.28 mmol/kg) protected against LPS-induced systemic inflammatory response syndrome (SIRS) in mice (all P < 0.05), in a manner similar to dexamethasone (0.03 mmol/kg). Casticin and chrysosplenol D suppressed LPS-induced release of IL-1 beta, IL-6 and MCP-1, inhibited cell migration, and reduced LPS-induced IκB and c-JUN phosphorylation in Raw264.7 cells. JNK inhibitor SP600125 blocked the inhibitory effect of chrysosplenol D on cytokine release. Conclusions: The flavonoids casticin and chrysosplenol D from A. annua L. inhibited inflammation in vitro and in vivo. - Highlights: • We report a new activity of the flavonoids present in Artemisia annua L. • These flavonoids inhibit croton oil-induced ear edema in mice. • These flavonoids protect against LPS-induced SIRS in

Non-destructive measurement of soybean leaf thickness via X-ray computed tomography allows the study of diel leaf growth rhythms in the third dimension.

Science.gov (United States)

Pfeifer, Johannes; Mielewczik, Michael; Friedli, Michael; Kirchgessner, Norbert; Walter, Achim

2018-01-01

Present-day high-resolution leaf growth measurements provide exciting insights into diel (24-h) leaf growth rhythms and their control by the circadian clock, which match photosynthesis with oscillating environmental conditions. However, these methods are based on measurements of leaf area or elongation and neglect diel changes of leaf thickness. In contrast, the influence of various environmental stress factors to which leaves are exposed to during growth on the final leaf thickness has been studied extensively. Yet, these studies cannot elucidate how variation in leaf area and thickness are simultaneously regulated and influenced on smaller time scales. Only few methods are available to measure the thickness of young, growing leaves non-destructively. Therefore, we evaluated X-ray computed tomography to simultaneously and non-invasively record diel changes and growth of leaf thickness and area. Using conventional imaging and X-ray computed tomography leaf area, thickness and volume growth of young soybean leaves were simultaneously and non-destructively monitored at three cardinal time points during night and day for a period of 80 h under non-stressful growth conditions. Reference thickness measurements on paperboards were in good agreement to CT measurements. Comparison of CT with leaf mass data further proved the consistency of our method. Exploratory analysis showed that measurements were accurate enough for recording and analyzing relative diel changes of leaf thickness, which were considerably different to those of leaf area. Relative growth rates of leaf area were consistently positive and highest during 'nights', while diel changes in thickness fluctuated more and were temporarily negative, particularly during 'evenings'. The method is suitable for non-invasive, accurate monitoring of diel variation in leaf volume. Moreover, our results indicate that diel rhythms of leaf area and thickness show some similarity but are not tightly coupled. These

What Is a Leaf? An Online Tutorial and Tests

Science.gov (United States)

Burrows, Geoffrey

2008-01-01

A leaf is a fundamental unit in botany and understanding what constitutes a leaf is fundamental to many plant science activities. My observations and subsequent testing indicated that many students could not confidently and consistently recognise a leaf from a leaflet, or recognise basic leaf arrangements and the various types of compound or…

Modeling the leaf angle dynamics in rice plant.

Directory of Open Access Journals (Sweden)

Yonghui Zhang

Full Text Available The leaf angle between stem and sheath (SSA is an important rice morphological trait. The objective of this study was to develop and validate a dynamic SSA model under different nitrogen (N rates for selected rice cultivars. The time-course data of SSA were collected in three years, and a dynamic SSA model was developed for different main stem leaf ranks under different N rates for two selected rice cultivars. SSA increased with tiller age. The SSA of the same leaf rank increased with increase in N rate. The maximum SSA increased with leaf rank from the first to the third leaf, then decreased from the third to the final leaf. The relationship between the maximum SSA and leaf rank on main stem could be described with a linear piecewise function. The change of SSA with thermal time (TT was described by a logistic equation. A variety parameter (the maximum SSA of the 3rd leaf on main stem and a nitrogen factor were introduced to quantify the effect of cultivar and N rate on SSA. The model was validated against data collected from both pot and field experiments. The relative root mean square error (RRMSE was 11.56% and 14.05%, respectively. The resulting models could be used for virtual rice plant modeling and plant-type design.

Screening Study of Leaf Terpene Concentration of 75 Borneo Rainforest Plant Species: Relationships with Leaf Elemental Concentrations and Morphology

Directory of Open Access Journals (Sweden)

Jordi Sardans

2015-01-01

Full Text Available Terpenes confer advantage in plant protection against abiotic stresses such as heat and drought and biotic stresses such as herbivore and pathogen attack. We conducted a screening of leaf mono- and sesquiterpene concentrations in 75 common woody plant species in the rainforest of Danum Valley (Borneo. Terpene compounds were found in 73 out of the 75 analysed species. Similar or lower proportions have been reported in other parts of the world. To our knowledge, this study reports for the first time the foliar concentration of mono- and/or sesquiterpene for 71 species and 39 genera not previously analyzed. Altogether 80 terpene compounds were determined across the species, and out of these only linalool oxide and (E- g -bisabolene had phylogenetic signal. A significant negative relationship between leaf monoterpene concentration and leaf length was observed, but leaf mono- and sesquitepene concentration were not related to any other leaf morphological trait nor to leaf elemental composition. Functions such as temperature protection, radiation protection or signaling and communication could underlie the high frequency of terpene-containing species of this tropical ecosystem which has multiple and very diverse interactions among multiple species.

Allelopathic potential of Artemisia arborescens: isolation, identification and quantification of phytotoxic compounds through fractionation-guided bioassays.

Science.gov (United States)

Araniti, Fabrizio; Lupini, Antonio; Sorgonà, Agostino; Conforti, Filomena; Marrelli, Mariangela; Statti, Giancarlo Antonio; Menichini, Francesco; Abenavoli, Maria Rosa

2013-01-01

The aerial part of Artemisia arborescens L. (Asteraceae) was extracted with water and methanol, and both extracts were fractionated using n-hexane, chloroform, ethyl acetate and n-butanol. The potential phytotoxicity of both crude extracts and their fractions were assayed in vitro on seed germination and root growth of lettuce (Lactuca sativa L.), a sensitive species largely employed in the allelopathy studies. The inhibitory activities were analysed by dose-response curves and the ED 50 were estimated. Crude extracts strongly inhibited both germination and root growth processes. The fraction-bioassay indicated the following hierarchy of phytotoxicity for both physiological processes: ethyl acetate ≥ n-hexane > chloroform ≥ n-butanol. On the n-hexane fraction, GC-MS analyses were carried out to characterise and quantify some of the potential allelochemicals. Twenty-one compounds were identified and three of them, camphor, trans-caryophyllene and pulegone were quantified.

Effect of Artemisia annua L. leaves essential oil and ethanol extract on behavioral assays

Directory of Open Access Journals (Sweden)

Fabio F. Perazzo

Full Text Available Artemisia annua has been used as a traditional plant for the treatment of malaria and fever in China because of the presence of its active compound, artemisinin. The present study evaluated the central activity of the essential oil and the crude ethanol extract of A. annua L. in animals as a part of a psychopharmacological screening of this plant. The extract was prepared in ethanol (AEE and the essential oil (AEO obtained by hydrodistillation, both with fresh leaves. Induced immobility, the forced swimming test (FST and the open-field test (OFT are well-known animal models to study drug-induced depression. The administration of A. annua essential oil or crude ethanol extract increased the immobility time in the FST and decreased other activities (ambulation, exploration, rearing and grooming in the OFT in animals. Both AEO and AEE prolonged pentobarbital-induced sleep as well, but the essential oil had a marked effect. Observing these results, it is possible to suggest that A. annua crude ethanol extract and essential oil could act as depressors on the Central Nervous System (CNS.

Measurement of Leaf Mass and Leaf Area of Oaks In A Mediterranean-climate Region For Biogenic Emission Estimation

Science.gov (United States)

Karlik, J.

Given the key role played by biogenic volatile organic compounds (BVOC) in tro- pospheric chemistry and regional air quality, it is critical to generate accurate BVOC emission inventories. Because several oak species have high BVOC emission rates, and oak trees are often of large stature with corresponding large leaf masses, oaks may be the most important genus of woody plants for BVOC emissions modeling in the natural landscapes of Mediterranean-climate regions. In California, BVOC emis- sions from oaks may mix with anthropogenic emissions from urban areas, leading to elevated levels of ozone. Data for leaf mass and leaf area for a stand of native blue oaks (Quercus douglasii) were obtained through harvest and leaf removal from 14 trees lo- cated in the Sierra Nevada foothills of central California. Trees ranged in height from 4.2 to 9.9 m, with trunk diameters at breast height of 14 to 85 cm. Mean leaf mass density was 730 g m-2 for the trees and had an overall value of 310 g m-2 for the site. Consideration of the surrounding grassland devoid of trees resulted in a value of about 150 g m-2, less than half of reported values for eastern U.S. oak woodlands, but close to a reported value for oaks found in St. Quercio, Italy. The mean value for leaf area index (LAI) for the trees at this site was 4.4 m2 m-2. LAI for the site was 1.8 m2 m-2, but this value was appropriate for the oak grove only; including the surrounding open grassland resulted in an overall LAI value of 0.9 m2 m-2 or less. A volumetric method worked well for estimating the leaf mass of the oak trees. Among allometric relationships investigated, trunk circumference, mean crown radius, and crown projec- tion were well correlated with leaf mass. Estimated emission of isoprene (mg C m-2 h-1) for the site based these leaf mass data and experimentally determined emission rate was similar to that reported for a Mediterranean oak woodland in France.

Leaf-jams - A new and unique leaf deposit in the ephemeral Hoanib River, NW Namibia: Origin and plant taphonomic implications

Energy Technology Data Exchange (ETDEWEB)

Hofmann, Christa-Ch. [University of Vienna, Department of Palaeontology, Palaeobotany Studies Group, Althanstrasse 14, 1090, Vienna (Austria); Rice, A. Hugh N. [University of Vienna, Department of Geodynamics and Sedimentology, Althanstrasse 14, 1090, Vienna (Austria)

2010-08-01

This paper documents a previously unrecorded type of leaf deposit, comprising essentially monospecific linear accumulations of Colophospermum mopane leaves on a point bar of the ephemeral Hoanib River, NW Namibia. In these 'leaf-jams', leaf laminae stand on edge, orientated more-or-less normal to bedding. Leaf-jams, which formed upstream of cobbles, clumps of grass and sticks wedged against the former two, were orientated subparallel to the adjacent meandering river-bed, such that over the 40 m of their occurrence, their mean azimuth changed by 59 anticlockwise downstream. The longest leaf-jam was 50 cm and contained approximately 500 leaves, as well as grass culms, twigs (C. mopane, Tamarix usneoides and unidentified) and medium- to fine-grained sand and silt. Individual leaf-jams were partially buried in the point bar sediments up to a depth of 3 cm. Leaf-jam formation occurred in the austral summer of 2006, during the waning stage of a major flood caused by anomalous tropical to extra-tropical storms. Their monospecifity is due to the overwhelming preponderance of the zonal taxon C. mopane in the catchment area, although the Khowarib Gorge contains a quite diverse azonal plant association due to the presence of a permanent water-seep. During leaf-jam formation, the water depth was less than the height of the cobbles (0.1 m), with stream flow-rates competent to transport medium-grained sand (velocity estimated at 0.5 m s{sup -} {sup 1}). Leaves must have been partially or fully waterlogged to inhibit buoyancy forces tending to lift them out of the developing leaf-jams, which propagated upstream in a manner comparable to longitudinal bars in a braided river. If fossilised, such deposits would probably lead to a very biased interpretation of the composition of the surrounding flora; the correct interpretation would be the one least favoured by palaeobotanists. (author)

Chromosome-damaging effect of betel leaf.

Science.gov (United States)

Sadasivan, G; Rani, G; Kumari, C K

1978-05-01

The chewing of betel leaf with other ingredients is a widespread addiction in India. The chromosome damaging effect was studied in human leukocyte cultures. There was an increase in the frequency of chromatid aberrations when the leaf extract was added to cultures.

Functional and chemical stability of a medicinal herb, Artemisia capillaris, following gamma sterilization

Energy Technology Data Exchange (ETDEWEB)

Jung, Uhee; Jeong, Ill Yun; Bae, Mun Hyoung; Byun, Myung Woo; Jo, Sung Kee [Radiation Research Center for Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

2007-08-15

The stability of functional and chemical properties of gamma-irradiated (10 kGy) Artemisia capillaris, a widely used herb in the traditional Oriental medicine, was investigated. Functional properties of the extracts of gamma-irradiated and non-irradiated A. capillaris were compared in antioxidant activities, such as 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical and superoxide anion radical scavenging, lipid peroxidation inhibition, and protection of lymphocyte and plasmid DNA. Their chemical properties were assessed by HPLC analysis, comparing with chlorogenic acid and caffeic acid, which were isolated from ethylacetate fraction as major compounds with strong antioxidant activities. No significant difference in functional properties between irradiated and non-irradiated A. capillaris was found in all antioxidant assays. Also HPLC analysis of ethyl acetate fractions of irradiated and non-irradiated A. capillaris revealed the preservation of chlorogenic acid ({sub t}R=3.124 min) and caffeic acid ({sub t}R=3.672 min), and showed almost the same pattern in the general peaks. These results suggest that the chemical components and antioxidant properties of A. capillaris are not affected largely by gamma-ray irradiation. Therefore, this study may provide evidence that the irradiated herbs retain their potential functional properties.

Does leaf chemistry differentially affect breakdown in tropical vs temperate streams? Importance of standardized analytical techniques to measure leaf chemistry

Science.gov (United States)

Marcelo Ard& #243; n; Catherine M. Pringle; Susan L. Eggert

2009-01-01

Comparisons of the effects of leaf litter chemistry on leaf breakdown rates in tropical vs temperate streams are hindered by incompatibility among studies and across sites of analytical methods used to measure leaf chemistry. We used standardized analytical techniques to measure chemistry and breakdown rate of leaves from common riparian tree species at 2 sites, 1...

7 CFR 29.2277 - Leaf scrap.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.2277 Section 29.2277 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists...

Impact of anatomical traits of maize (Zea mays L.) leaf as affected by nitrogen supply and leaf age on bundle sheath conductance.

Science.gov (United States)

Retta, Moges; Yin, Xinyou; van der Putten, Peter E L; Cantre, Denis; Berghuijs, Herman N C; Ho, Quang Tri; Verboven, Pieter; Struik, Paul C; Nicolaï, Bart M

2016-11-01

The mechanism of photosynthesis in C 4 crops depends on the archetypal Kranz-anatomy. To examine how the leaf anatomy, as altered by nitrogen supply and leaf age, affects the bundle sheath conductance (g bs ), maize (Zea mays L.) plants were grown under three contrasting nitrogen levels. Combined gas exchange and chlorophyll fluorescence measurements were done on fully grown leaves at two leaf ages. The measured data were analysed using a biochemical model of C 4 photosynthesis to estimate g bs . The leaf microstructure and ultrastructure were quantified using images obtained from micro-computed tomography and microscopy. There was a strong positive correlation between g bs and leaf nitrogen content (LNC) while old leaves had lower g bs than young leaves. Leaf thickness, bundle sheath cell wall thickness and surface area of bundle sheath cells per unit leaf area (S b ) correlated well with g bs although they were not significantly affected by LNC. As a result, the increase of g bs with LNC was little explained by the alteration of leaf anatomy. In contrast, the combined effect of LNC and leaf age on S b was responsible for differences in g bs between young leaves and old leaves. Future investigations should consider changes at the level of plasmodesmata and membranes along the CO 2 leakage pathway to unravel LNC and age effects further. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Photoperiod-H1 (Ppd-H1) Controls Leaf Size1[OPEN

Science.gov (United States)

Digel, Benedikt; Tavakol, Elahe; Verderio, Gabriele; Xu, Xin

2016-01-01

Leaf size is a major determinant of plant photosynthetic activity and biomass; however, it is poorly understood how leaf size is genetically controlled in cereal crop plants like barley (Hordeum vulgare). We conducted a genome-wide association scan for flowering time, leaf width, and leaf length in a diverse panel of European winter cultivars grown in the field and genotyped with a single-nucleotide polymorphism array. The genome-wide association scan identified PHOTOPERIOD-H1 (Ppd-H1) as a candidate gene underlying the major quantitative trait loci for flowering time and leaf size in the barley population. Microscopic phenotyping of three independent introgression lines confirmed the effect of Ppd-H1 on leaf size. Differences in the duration of leaf growth and consequent variation in leaf cell number were responsible for the leaf size differences between the Ppd-H1 variants. The Ppd-H1-dependent induction of the BARLEY MADS BOX genes BM3 and BM8 in the leaf correlated with reductions in leaf size and leaf number. Our results indicate that leaf size is controlled by the Ppd-H1- and photoperiod-dependent progression of plant development. The coordination of leaf growth with flowering may be part of a reproductive strategy to optimize resource allocation to the developing inflorescences and seeds. PMID:27457126

Leaf wetness distribution within a potato crop

Science.gov (United States)

Heusinkveld, B. G.

2010-07-01

The Netherlands has a mild maritime climate and therefore the major interest in leaf wetness is associated with foliar plant diseases. During moist micrometeorological conditions (i.e. dew, fog, rain), foliar fungal diseases may develop quickly and thereby destroy a crop quickly. Potato crop monocultures covering several hectares are especially vulnerable to such diseases. Therefore understanding and predicting leaf wetness in potato crops is crucial in crop disease control strategies. A field experiment was carried out in a large homogeneous potato crop in the Netherlands during the growing season of 2008. Two innovative sensor networks were installed as a 3 by 3 grid at 3 heights covering an area of about 2 hectares within two larger potato crops. One crop was located on a sandy soil and one crop on a sandy peat soil. In most cases leaf wetting starts in the top layer and then progresses downward. Leaf drying takes place in the same order after sunrise. A canopy dew simulation model was applied to simulate spatial leaf wetness distribution. The dew model is based on an energy balance model. The model can be run using information on the above-canopy wind speed, air temperature, humidity, net radiation and within canopy air temperature, humidity and soil moisture content and temperature conditions. Rainfall was accounted for by applying an interception model. The results of the dew model agreed well with the leaf wetness sensors if all local conditions were considered. The measurements show that the spatial correlation of leaf wetness decreases downward.

Foraging on individual leaves by an intracellular feeding insect is not associated with leaf biomechanical properties or leaf orientation.

Directory of Open Access Journals (Sweden)

Justin Fiene

Full Text Available Nearly all herbivorous arthropods make foraging-decisions on individual leaves, yet systematic investigations of the adaptive significance and ecological factors structuring these decisions are rare with most attention given to chewing herbivores. This study investigated why an intracellular feeding herbivore, Western flower thrips (WFT Frankliniella occidentalis Pergande, generally avoids feeding on the adaxial leaf surface of cotton cotyledons. WFT showed a significant aversion to adaxial-feeding even when excised-cotyledons were turned up-side (abaxial-side 'up', suggesting that negative-phototaxis was not a primary cause of thrips foraging patterns. No-choice bioassays in which individual WFT females were confined to either the abaxial or adaxial leaf surface showed that 35% fewer offspring were produced when only adaxial feeding was allowed, which coincided with 32% less plant feeding on that surface. To test the hypothesis that leaf biomechanical properties inhibited thrips feeding on the adaxial surface, we used a penetrometer to measure two variables related to the 'toughness' of each leaf surface. Neither variable negatively co-varied with feeding. Thus, while avoiding the upper leaf surface was an adaptive foraging strategy, the proximate cause remains to be elucidated, but is likely due, in part, to certain leaf properties that inhibit feeding.

7 CFR 29.2278 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.2278 Section 29.2278 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... structure. The cell development of a leaf as indicated by its porosity. (See chart, § 29.2351.) ...

7 CFR 29.2529 - Leaf scrap.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

Inheritance of okra leaf type in different genetic backgrounds and its ...

African Journals Online (AJOL)

use

2011-11-21

Nov 21, 2011 ... discontinuous variation for leaf shape in F2 generations of three crosses .... Variable classes in leaf types (a) Normal leaf (b) Okra leaf (c) Sub-okra leaf. ..... insect pests on different isogenic lines of cotton variety H-777. J.

Waiting for the Leaf; Warten auf den Leaf

Energy Technology Data Exchange (ETDEWEB)

Wilms, Jan

2012-01-15

Nissan will be the first manufacturer to launch an electric vehicle of the VW Golf category in the German market. With a mileage of about 170 km and a roomy passenger compartment, the Leaf promises much comfort. In the US market, it was launched two years ago. Was it worth while waiting for?.

From leaf to whole-plant water use efficiency (WUE in complex canopies: Limitations of leaf WUE as a selection target

Directory of Open Access Journals (Sweden)

Hipólito Medrano

2015-06-01

Full Text Available Plant water use efficiency (WUE is becoming a key issue in semiarid areas, where crop production relies on the use of large volumes of water. Improving WUE is necessary for securing environmental sustainability of food production in these areas. Given that climate change predictions include increases in temperature and drought in semiarid regions, improving crop WUE is mandatory for global food production. WUE is commonly measured at the leaf level, because portable equipment for measuring leaf gas exchange rates facilitates the simultaneous measurement of photosynthesis and transpiration. However, when those measurements are compared with daily integrals or whole-plant estimates of WUE, the two sometimes do not agree. Scaling up from single-leaf to whole-plant WUE was tested in grapevines in different experiments by comparison of daily integrals of instantaneous water use efficiency [ratio between CO2 assimilation (AN and transpiration (E; AN/E] with midday AN/E measurements, showing a low correlation, being worse with increasing water stress. We sought to evaluate the importance of spatial and temporal variation in carbon and water balances at the leaf and plant levels. The leaf position (governing average light interception in the canopy showed a marked effect on instantaneous and daily integrals of leaf WUE. Night transpiration and respiration rates were also evaluated, as well as respiration contributions to total carbon balance. Two main components were identified as filling the gap between leaf and whole plant WUE: the large effect of leaf position on daily carbon gain and water loss and the large flux of carbon losses by dark respiration. These results show that WUE evaluation among genotypes or treatments needs to be revised.

A finger leaf design for dual layer MLCs

International Nuclear Information System (INIS)

Cui Weijie; Dai Jianrong

2010-01-01

Objective: To introduce a finger leaf design that is applied to dual layer MLCs. Methods: An optimization model was firstly constructed to describe the problem of determining leaf end shapes,and the corresponding problems were then solved by the simplex search method or the simulated annealing technique. Optimal parameters for arc shapes of leaf end projections were obtained, and a comparison was done between optimized MLCs and conventional MLCs in terms of field conformity. The optimization process was based on 634 target fields selected from the patient data base of a treatment planning system. Areas of these fields ranged from 20.0 to 602.7 cm with a mean and its standard deviation of (125.7 ± 0.0) cm 2 . Results: The optimized leaf end shapes projected to the isocenter plane were semicircles. With the finger leaf design, the total area of discrepancy regions between MLC fields and target fields was reduced by 32.3%. Conclusions: The finger leaf design improves the conformity of the MLC shaped fields to the desired target fields. (authors)

Leaf Wetness within a Lily Canopy

NARCIS (Netherlands)

Jacobs, A.F.G.; Heusinkveld, B.G.; Klok, E.J.

2005-01-01

A wetness duration experiment was carried out within a lily field situated adjacent to coastal dunes in the Netherlands. A within-canopy model was applied to simulate leaf wetness in three layers, with equal leaf area indices, within the canopy. This simulation model is an extension of an existing

How Does Temperature Impact Leaf Size and Shape in Four Woody Dicot Species? Testing the Assumptions of Leaf Physiognomy-Climate Models

Science.gov (United States)

McKee, M.; Royer, D. L.

2017-12-01

The physiognomy (size and shape) of fossilized leaves has been used to reconstruct the mean annual temperature of ancient environments. Colder temperatures often select for larger and more abundant leaf teeth—serrated edges on leaf margins—as well as a greater degree of leaf dissection. However, to be able to accurately predict paleotemperature from the morphology of fossilized leaves, leaves must be able to react quickly and in a predictable manner to changes in temperature. We examined the extent to which temperature affects leaf morphology in four tree species: Carpinus caroliniana, Acer negundo, Ilex opaca, and Ostrya virginiana. Saplings of these species were grown in two growth cabinets under contrasting temperatures (17 and 25 °C). Compared to the cool treatment, in the warm treatment Carpinus caroliniana leaves had significantly fewer leaf teeth and a lower ratio of total number of leaf teeth to internal perimeter; and Acer negundo leaves had a significantly lower feret diameter ratio (a measure of leaf dissection). In addition, a two-way ANOVA tested the influence of temperature and species on leaf physiognomy. This analysis revealed that all plants, regardless of species, tended to develop more highly dissected leaves with more leaf teeth in the cool treatment. Because the cabinets maintained equivalent moisture, humidity, and CO2 concentration between the two treatments, these results demonstrate that these species could rapidly adapt to changes in temperature. However, not all of the species reacted identically to temperature changes. For example, Acer negundo, Carpinus caroliniana, and Ostrya virginiana all had a higher number of total teeth in the cool treatment compared to the warm treatment, but the opposite was true for Ilex opaca. Our work questions a fundamental assumption common to all models predicting paleotemperature from the physiognomy of fossilized leaves: a given climate will inevitably select for the same leaf physiognomy

7 CFR 29.2530 - Leaf structure.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf structure. 29.2530 Section 29.2530 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2530 Leaf structure. The cell development of...

Importance of Secondary Metabolites for Leaf Beetles (Coleoptera: Chrysomelidae

Directory of Open Access Journals (Sweden)

A. N. EKİZ

2014-06-01

Full Text Available Leaf beetles (Chrysomelidae are one of the most diverse families of herbivorous insects. Many of them are important agricultural pests and cause remarkable loss of crop and money as well. Plant leaves and roots are primary food source of both larva and adults of leaf beetles. Plants produce many secondary metabolites in reaction to herbivore insects. It is a well-known phenomenon that quantity and variety of secondary metabolites in plant leaves may change in response to insect attacks. Herbivore insects have to deal with such defensive secondary chemicals and overcome either by detoxifying or storing them. Accordingly, many specialist herbivores coevolved with their host plant. Certain phenolic glycosides may reduce leaf beetle feeding. Condensed tannins are anti-herbivore defenses against leaf chewing beetles, including leaf beetles. Flavonoid compounds are feeding deterrents for many flea leaf beetles. Cinnamic acid derivatives are other known feeding deterrents for leaf beetles. Secondary metabolites quantity and nutritional quality of host plants are not only important for feeding but also for providing enemy-free space and suitable oviposition sites.

Models for leaf area estimation in dwarf pigeon pea by leaf dimensions

Directory of Open Access Journals (Sweden)

Rafael Vieira Pezzini

2018-03-01

Full Text Available ABSTRACT This study aims to determine the most suitable model to estimate the leaf area of dwarf pigeon pea in function of the leaf central leaflet dimension. Six samplings of 200 leaves were performed in the first experiment, at 36, 42, 50, 56, 64, and 72 days after emergence (DAE. In the second experiment, seven samplings of 200 leaves were performed at 29, 36, 43, 49, 57, 65, and 70 DAE, totaling 2600 leaves. The length (L and width (W of the central leaflet were measured in all leaves composed by left, central, and right leaflets, the product of length times width (LW was calculated, and the leaf area (Y – sum of left, central, and right leaflet areas was determined by digital images. Linear, power, quadratic, and cubic models of Y as function of L, W, and LW were built using data from the second experiment. Leaves from the first experiment were used to validate the models. In dwarf pigeon pea, the linear (Ŷ = – 0.4088 + 1.6669x, R2 = 0.9790 is preferable, but power (Ŷ = 1.6097x1.0065, R2 = 0.9766, quadratic (Ŷ = – 0.3625 + 1.663x + 0.00007x2, R2 = 0.9790, and cubic (Ŷ = 0.7216 + 1.522x + 0.005x2 – 5E–05x3, R2 = 0.9791 models in function of LW are also suitable to estimate the leaf area obtained by digital images. The power model (Ŷ = 5.2508x1.7868, R2 = 0.95 based on the central leaflet width is less laborious because requires only one variable, but it presents accuracy reduction.

Leveraging multiple datasets for deep leaf counting

OpenAIRE

Dobrescu, Andrei; Giuffrida, Mario Valerio; Tsaftaris, Sotirios A

2017-01-01

The number of leaves a plant has is one of the key traits (phenotypes) describing its development and growth. Here, we propose an automated, deep learning based approach for counting leaves in model rosette plants. While state-of-the-art results on leaf counting with deep learning methods have recently been reported, they obtain the count as a result of leaf segmentation and thus require per-leaf (instance) segmentation to train the models (a rather strong annotation). Instead, our method tre...

Resistance in winter barley against Ramularia leaf spot

DEFF Research Database (Denmark)

Hjortshøj, Rasmus Lund

Ramularia leaf spot is an emerging disease in barley caused by R. collo-cygni. At present little is known about the resistance mechanisms carried out by the host plant to avoid disease development. Nor is the lifecycle of the fungus or its populations structure fully understood. To gain insight....... fulvum-tomato and S. tritici-wheat in order to find modelsystems to enhance interpretation of results from R. collo-cygni-barley interaction. Results from the mapping showed that resistance to Ramularia leaf spot is controlled by a number of QTL’s, some of which co-locate with other physiological traits....... The populations further segregated for physiological leaf spots, a phenomenon related to the leaf damage imposed by Rubellin, although, resistance to physiological leafspots appeared to come from the Ramularia leaf spot susceptible parent. The toxin assay further supported this result as the genotypes susceptible...

Isolation and Characterization of Three New Monoterpene Synthases from Artemisia annua

Science.gov (United States)

Ruan, Ju-Xin; Li, Jian-Xu; Fang, Xin; Wang, Ling-Jian; Hu, Wen-Li; Chen, Xiao-Ya; Yang, Chang-Qing

2016-01-01

Artemisia annua, an annual herb used in traditional Chinese medicine, produces a wealth of monoterpenes and sesquiterpenes, including the well-known sesquiterpene lactone artemisinin, an active ingredient in the treatment for malaria. Here we report three new monoterpene synthases of A. annua. From a glandular trichome cDNA library, monoterpene synthases of AaTPS2, AaTPS5, and AaTPS6, were isolated and characterized. The recombinant proteins of AaTPS5 and AaTPS6 produced multiple products with camphene and 1,8-cineole as major products, respectively, and AaTPS2 produced a single product, β-myrcene. Although both Mg2+ and Mn2+ were able to support their catalytic activities, altered product spectrum was observed in the presence of Mn2+ for AaTPS2 and AaTPS5. Analysis of extracts of aerial tissues and root of A. annua with gas chromatography–mass spectrometry detected more than 20 monoterpenes, of which the three enzymes constituted more than 1/3 of the total. Mechanical wounding induced the expression of all three monoterpene synthase genes, and transcript levels of AaTPS5 and AaTPS6 were also elevated after treatments with phytohormones of methyl jasmonate, salicylic acid, and gibberellin, suggesting a role of these monoterpene synthases in plant–environment interactions. The three new monoterpene synthases reported here further our understanding of molecular basis of monoterpene biosynthesis and regulation in plant. PMID:27242840

Isolation and characterization of three new monoterpene synthases from Artemisia annua

Directory of Open Access Journals (Sweden)

Ju-Xin eRuan

2016-05-01

Full Text Available Artemisia annua, an annual herb used in traditional Chinese medicine, produces a wealth of monoterpenes and sesquiterpenes, including the well-known sesquiterpene lactone artemisinin, an active ingredient in the treatment for malaria. Here we report three new monoterpene synthases of A. annua. From a glandular trichome cDNA library, monoterpene synthases of AaTPS2, AaTPS5 and AaTPS6, were isolated and characterized. The recombinant proteins of AaTPS5 and AaTPS6 produced multiple products with camphene and 1,8-cineole as major products, respectively, and AaTPS2 produced a single product, β-myrcene. Although both Mg2+ and Mn2+ were able to support their catalytic activities, altered product spectrum was observed in the presence of Mn2+ for AaTPS2 and AaTPS5. Analysis of extracts of aerial tissues and root of A. annua with gas chromatography-mass spectrometry (GC-MS detected more than 20 monoterpenes, of which the three enzymes constituted more than 1/3 of the total. Mechanical wounding induced the expression of all three monoterpene synthase genes, and transcript levels of AaTPS5 and AaTPS6 were also elevated after treatments with phytohormones of methyl jasmonate (MeJA, salicylic acid (SA and gibberellin (GA, suggesting a role of these monoterpene synthases in plant-environment interactions. The three new monoterpene synthases reported here further our understanding of molecular basis of monoterpene biosynthesis and regulation in plant.

[Latitude variation mechanism of leaf traits of Metasequoia glyptostroboides in eastern coastal China].

Science.gov (United States)

Guo, Wei Hong; Wang, Hua; Yu, Mu Kui; Wu, Tong Gui; Han, You Zhi

2017-03-18

We analyzed the rules of Metasequoia glyptostroboides along with latitude, including leaf length, leaf width, leaf perimeter, leaf area, ratio of leaf length to width, specific leaf area (SLA), and leaf dry mass based on eight stands growing at different latitudes in the coastal area of eastern China, as well as their relationships with climatic and soil factors. The results showed that the leaf length, leaf width and leaf perimeter increased with increasing latitude, while the leaf area and SLA firstly increased and then decreased. The mean annual temperature and annual precipitation were the major environmental factors affecting the leaf traits along latitude gradient. With the increase of soil N content, the SLA decreased firstly and then increased, while the leaf mass decreased significantly. With the increase of soil P content, the SLA increased, and the leaf mass decreased significantly.

Endophytic fungi reduce leaf-cutting ant damage to seedlings

Science.gov (United States)

Bittleston, L. S.; Brockmann, F.; Wcislo, W.; Van Bael, S. A.

2011-01-01

Our study examines how the mutualism between Atta colombica leaf-cutting ants and their cultivated fungus is influenced by the presence of diverse foliar endophytic fungi (endophytes) at high densities in tropical leaf tissues. We conducted laboratory choice trials in which ant colonies chose between Cordia alliodora seedlings with high (Ehigh) or low (Elow) densities of endophytes. The Ehigh seedlings contained 5.5 times higher endophyte content and a greater diversity of fungal morphospecies than the Elow treatment, and endophyte content was not correlated with leaf toughness or thickness. Leaf-cutting ants cut over 2.5 times the leaf area from Elow relative to Ehigh seedlings and had a tendency to recruit more ants to Elow plants. Our findings suggest that leaf-cutting ants may incur costs from cutting and processing leaves with high endophyte loads, which could impact Neotropical forests by causing variable damage rates within plant communities. PMID:20610420

Consequences of leaf calibration errors on IMRT delivery

International Nuclear Information System (INIS)

Sastre-Padro, M; Welleweerd, J; Malinen, E; Eilertsen, K; Olsen, D R; Heide, U A van der

2007-01-01

IMRT treatments using multi-leaf collimators may involve a large number of segments in order to spare the organs at risk. When a large proportion of these segments are small, leaf positioning errors may become relevant and have therapeutic consequences. The performance of four head and neck IMRT treatments under eight different cases of leaf positioning errors has been studied. Systematic leaf pair offset errors in the range of ±2.0 mm were introduced, thus modifying the segment sizes of the original IMRT plans. Thirty-six films were irradiated with the original and modified segments. The dose difference and the gamma index (with 2%/2 mm criteria) were used for evaluating the discrepancies between the irradiated films. The median dose differences were linearly related to the simulated leaf pair errors. In the worst case, a 2.0 mm error generated a median dose difference of 1.5%. Following the gamma analysis, two out of the 32 modified plans were not acceptable. In conclusion, small systematic leaf bank positioning errors have a measurable impact on the delivered dose and may have consequences for the therapeutic outcome of IMRT

Generality of leaf trait relationships: A test across six biomes

Energy Technology Data Exchange (ETDEWEB)

Reich, P.B. [Univ. of Minnesota, Saint Paul, MN (United States). Dept. of Forest Resources; Ellsworth, D.S. [Brookhaven National Lab., Upton, NY (United States). Dept. of Applied Science; Walters, M.B. [Michigan State Univ., East Lansing, MI (United States). Dept. of Forestry; Vose, J.M. [Forest Service, Otto, NC (United States). Coweeta Hydrological Lab.; Gresham, C. [Clemson Univ., Georgetown, SC (United States). Baruch Forest Inst.; Volin, J.C. [Florida Atlantic Univ., Davie, FL (United States). Div. of Science; Bowman, W.D. [Inst. of Arctic and Alpine Research, Boulder, CO (United States). Mountain Research Station]|[Univ. of Colorado, Boulder, CO (United States). Dept. of Evolutionary, Population, and Organismic Biology

1999-09-01

Convergence in interspecific leaf trait relationships across diverse taxonomic groups and biomes would have important evolutionary and ecological implications. Such convergence has been hypothesized to result from trade-offs that limit the combination of plant traits for any species. Here the authors address this issue by testing for biome differences in the slope and intercept of interspecific relationships among leaf traits: longevity, net photosynthetic capacity (A{sub max}), leaf diffusive conductance (G{sub S}), specific leaf area (SLA), and nitrogen (N) status, for more than 100 species in six distinct biomes of the Americas. The six biomes were: alpine tundra-subalpine forest ecotone, cold temperate forest-prairie ecotone, montane cool temperate forest, desert shrubland, subtropical forest, and tropical rain forest. Despite large differences in climate and evolutionary history, in all biomes mass-based leaf N (N{sub mass}), SLA, G{sub S}, and A{sub max} were positively related to one another and decreased with increasing leaf life span. The relationships between pairs of leaf traits exhibited similar slopes among biomes, suggesting a predictable set of scaling relationships among key leaf morphological, chemical, and metabolic traits that are replicated globally among terrestrial ecosystems regardless of biome or vegetation type. However, the intercept (i.e., the overall elevation of regression lines) of relationships between pairs of leaf traits usually differed among biomes. With increasing aridity across sites, species had greater A{sub max} for a given level of G{sub S} and lower SLA for any given leaf life span. Using principal components analysis, most variation among species was explained by an axis related to mass-based leaf traits (A{sub max}, N, and SLA) while a second axis reflected climate, G{sub S}, and other area-based leaf traits.

Effects of some growth regulating applications on leaf yield, raw ...

African Journals Online (AJOL)

This study investigated the effects of repetitive applications of herbagreen (HG), humic acid (HA), combined foliar fertilizer (CFF) and HG+CFF performed in the Müsküle grape variety grafted on 5 BB rootstock on fresh or pickled leaf size and leaf raw cellulose content. HA application increased leaf area and leaf water ...

Patterns of leaf morphology and leaf N content in relation to winter temperatures in three evergreen tree species

Science.gov (United States)

Mediavilla, Sonia; Gallardo-López, Victoria; González-Zurdo, Patricia; Escudero, Alfonso

2012-09-01

The competitive equilibrium between deciduous and perennial species in a new scenario of climate change may depend closely on the productivity of leaves along the different seasons of the year and on the morphological and chemical adaptations required for leaf survival during the different seasons. The aim of the present work was to analyze such adaptations in the leaves of three evergreen species ( Quercus ilex, Q. suber and Pinus pinaster) and their responses to between-site differences in the intensity of winter harshness. We explore the hypothesis that the harshness of winter would contribute to enhancing the leaf traits that allow them to persist under conditions of stress. The results revealed that as winter harshness increases a decrease in leaf size occurs in all three species, together with an increase in the content of nitrogen per unit leaf area and a greater leaf mass per unit area, which seems to be achieved only through increased thickness, with no associated changes in density. P. pinaster was the species with the most intense response to the harshening of winter conditions, undergoing a more marked thickening of its needles than the two Quercus species. Our findings thus suggest that lower winter temperatures involve an increase in the cost of leaf production of evergreen species, which must be taken into account in the estimation of the final cost and benefit balance of evergreens. Such cost increases would be more pronounced for those species that, like P. pinaster, show a stronger response to the winter cold.

Dynamics of vacuum-sealed, double-leaf partitions

Science.gov (United States)

Kavanaugh, Joshua Stephen

The goal of this research is to investigate the feasibility and potential effectiveness of using vacuum-sealed, double-leaf partitions for applications in noise control. Substantial work has been done previously on double-leaf partitions where the acoustics of the inner chamber and mechanical vibrations of structural supports are passively and actively controlled. The work presented here is unique in that the proposed system aims to eliminate the need for active acoustic control of transmitted acoustic energy by removing all the air between the two panels of the double partition. Therefore, the only remaining energy paths would be along the boundary and at the points where there are intermediate structural supports connecting the two panels. The eventual goal of the research is to develop a high-loss double-leaf partition that simplifies active control by removing the need for control of the air cavity and channeling all the energy into discrete structural paths. The work presented here is a first step towards the goal of designing a high-loss, actively-controlled double-leaf partition with an air-evacuated inner chamber. One experiment is conducted to investigate the effects of various levels of vacuum on the response of a double-leaf partition whose panels are mechanically coupled only at the boundary. Another experiment is conducted which investigates the effect of changing the stiffness of an intermediate support coupling the two panels of a double-leaf partition in which a vacuum has been applied to the inner cavity. The available equipment was able to maintain a 99% vacuum between the panels. Both experiments are accompanied by analytical models used to investigate the importance of various dynamic parameters. Results show that the vacuum-sealed system shows some potential for increased transmission loss, primarily by the changing the natural frequencies of the double-leaf partition.

Predicting tropical plant physiology from leaf and canopy spectroscopy.

Science.gov (United States)

Doughty, Christopher E; Asner, Gregory P; Martin, Roberta E

2011-02-01

A broad regional understanding of tropical forest leaf photosynthesis has long been a goal for tropical forest ecologists, but it has remained elusive due to difficult canopy access and high species diversity. Here we develop an empirical model to predict sunlit, light-saturated, tropical leaf photosynthesis using leaf and simulated canopy spectra. To develop this model, we used partial least squares (PLS) analysis on three tropical forest datasets (159 species), two in Hawaii and one at the biosphere 2 laboratory (B2L). For each species, we measured light-saturated photosynthesis (A), light and CO(2) saturated photosynthesis (A(max)), respiration (R), leaf transmittance and reflectance spectra (400-2,500 nm), leaf nitrogen, chlorophyll a and b, carotenoids, and leaf mass per area (LMA). The model best predicted A [r(2) = 0.74, root mean square error (RMSE) = 2.9 μmol m(-2) s(-1))] followed by R (r(2) = 0.48), and A(max) (r(2) = 0.47). We combined leaf reflectance and transmittance with a canopy radiative transfer model to simulate top-of-canopy reflectance and found that canopy spectra are a better predictor of A (RMSE = 2.5 ± 0.07 μmol m(-2) s(-1)) than are leaf spectra. The results indicate the potential for this technique to be used with high-fidelity imaging spectrometers to remotely sense tropical forest canopy photosynthesis.

Specific characteristics of essential oils of four Artemisia species from the Mongolian Trans-Altai Gobi

Directory of Open Access Journals (Sweden)

N. Javzmaa

2016-03-01

Full Text Available The essential oil compositions of four Artemisia species in Mongolian Trans-Altai Gobi were studied by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS. The oil from A.macrocephala Jacq and A.dracunculus Ledeb. were characterized by the presence of monoterpene hydrocarbons and oxygenated monoterpeneoids predominately. E-nerolidol (26.95%, methyleugenol (23.29% and sabinene (13.21% were found as main components in the essential oils of A.dracunculus. A.macrocephalla was characterized by the presence of chamazulene (13.8%, cineol (11.7%, myrcene (9.0%, germacrene-D (7.1%. A.anethifolia Web was characterized by the presence of fragrant compounds as camphor (26.05%, α-thujone (10.1%, borneol (5.1%. Davanone and davanone derivatives were also detected in the sample in amount of 7.7% in total. A.scoparia Waldst differed by domination of monoterpene hydrocarbons (78.9% with (Z- β-ocimene (29.24%, α-pinene (15.19%, limonene (10.27% and myrcene (9.61%.Mongolian Journal of Chemistry 16 (42, 2015, 34-38

The essential oil of Artemisia capillaris protects against CCl4-induced liver injury in vivo

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Qinghan Gao

Full Text Available Abstract To study the hepatoprotective effect of the essential oil of Artemisia capillaris Thunb., Asteraceae, on CCl4-induced liver injury in mice, the levels of serum aspartate aminotransferase and alanine aminotransferase, hepatic levels of reduced glutathione, activity of glutathione peroxidase, and the activities of superoxide dismutase and malondialdehyde were assayed. Administration of the essential oil of A. capillaris at 100 and 50 mg/kg to mice prior to CCl4 injection was shown to confer stronger in vivo protective effects and could observably antagonize the CCl4-induced increase in the serum alanine aminotransferase and aspartate aminotransferase activities and malondialdehyde levels as well as prevent CCl4-induced decrease in the antioxidant superoxide dismutase activity, glutathione level and glutathione peroxidase activity (p < 0.01. The oil mainly contained β-citronellol, 1,8-cineole, camphor, linalool, α-pinene, β-pinene, thymol and myrcene. This finding demonstrates that the essential oil of A. capillaris can protect hepatic function against CCl4-induced liver injury in mice.

The Effect of Leaf Stacking on Leaf Reflectance and Vegetation Indices Measured by Contact Probe during the Season

Czech Academy of Sciences Publication Activity Database

Neuwirthová, E.; Lhotáková, Z.; Albrechtová, Jana

2017-01-01

Roč. 17, č. 6 (2017), s. 1-23, č. článku 1202. ISSN 1424-8220 Institutional support: RVO:67985939 Keywords : broadleaved trees * leaf optical properties * leaf traits Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 2.677, year: 2016

BOREAS TE-9 NSA Leaf Chlorophyll Density

Science.gov (United States)

Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Margolis, Hank; Sy, Mikailou

2000-01-01

The BOREAS TE-9 team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. These data were collected to help provide an explanation of potential seasonal and spatial changes of leaf pigment properties in boreal forest species at the NSA. At different dates (FFC-Winter, FFC-Thaw, IFC-1, IFC-2, and IMC-3), foliage samples were collected from the upper third of the canopy for five NSA sites (YJP, OJP, OBS, UBS, and OA) near Thompson, Manitoba. Subsamples of 100 needles for black spruce, 20 needles for jack pine, and single leaf for trembling aspen were cut into pieces and immersed in a 20-mL DMF aliquot in a Nalgene test tube. The extracted foliage materials were then oven-dried at 68 C for 48 hours and weighed. Extracted leaf dry weight was converted to a total leaf area basis to express the chlorophyll content in mg/sq cm of total leaf area. The data are provided in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Silver nano fabrication using leaf disc of Passiflora foetida Linn

Science.gov (United States)

Lade, Bipin D.; Patil, Anita S.

2017-06-01

The main purpose of the experiment is to develop a greener low cost SNP fabrication steps using factories of secondary metabolites from Passiflora leaf extract. Here, the leaf extraction process is omitted, and instead a leaf disc was used for stable SNP fabricated by optimizing parameters such as a circular leaf disc of 2 cm (1, 2, 3, 4, 5) instead of leaf extract and grade of pH (7, 8, 9, 11). The SNP synthesis reaction is tried under room temperature, sun, UV and dark condition. The leaf disc preparation steps are also discussed in details. The SNP obtained using (1 mM: 100 ml AgNO3+ singular leaf disc: pH 9, 11) is applied against featured room temperature and sun condition. The UV spectroscopic analysis confirms that sun rays synthesized SNP yields stable nano particles. The FTIR analysis confirms a large number of functional groups such as alkanes, alkyne, amines, aliphatic amine, carboxylic acid; nitro-compound, alcohol, saturated aldehyde and phenols involved in reduction of silver salt to zero valent ions. The leaf disc mediated synthesis of silver nanoparticles, minimizes leaf extract preparation step and eligible for stable SNP synthesis. The methods sun and room temperature based nano particles synthesized within 10 min would be use certainly for antimicrobial activity.

Reading the Leaves: A Comparison of Leaf Rank and Automated Areole Measurement for Quantifying Aspects of Leaf Venation

Directory of Open Access Journals (Sweden)

Walton A. Green

2014-08-01

Full Text Available The reticulate venation that is characteristic of a dicot leaf has excited interest from systematists for more than a century, and from physiological and developmental botanists for decades. The tools of digital image acquisition and computer image analysis, however, are only now approaching the sophistication needed to quantify aspects of the venation network found in real leaves quickly, easily, accurately, and reliably enough to produce biologically meaningful data. In this paper, we examine 120 leaves distributed across vascular plants (representing 118 genera and 80 families using two approaches: a semiquantitative scoring system called “leaf ranking,” devised by the late Leo Hickey, and an automated image-analysis protocol. In the process of comparing these approaches, we review some methodological issues that arise in trying to quantify a vein network, and discuss the strengths and weaknesses of automatic data collection and human pattern recognition. We conclude that subjective leaf rank provides a relatively consistent, semiquantitative measure of areole size among other variables; that modal areole size is generally consistent across large sections of a leaf lamina; and that both approaches—semiquantitative, subjective scoring; and fully quantitative, automated measurement—have appropriate places in the study of leaf venation.

Up-scaling of water use efficiency from leaf to canopy as based on leaf gas exchange relationships and the modeled in-canopy light distribution

DEFF Research Database (Denmark)

Linderson, Maj-Lena; Mikkelsen, Teis Nørgaard; Ibrom, Andreas

2012-01-01

The aim of this study was to evaluate the extent to which water use efficiency (WUE) at leaf scale can be used to assess WUE at canopy scale, leaf WUE being assumed to be a constant function of vapor pressure deficit and to thus not be dependent upon other environmental factors or varying leaf...... properties. Leaf WUE and its variability and dependencies were assessed using leafgas-exchange measurements obtained during two growing seasons, 1999 and 2000, at the Soroe beech forest study site on Zealand in Denmark. It was found that the VPD-normalized leaf WUE, WUEnormleaf, although dependent...

Betel leaf in stoma care.

Science.gov (United States)

Banu, Tahmina; Talukder, Rupom; Chowdhury, Tanvir Kabir; Hoque, Mozammel

2007-07-01

Construction of a stoma is a common procedure in pediatric surgical practice. For care of these stomas, commercially available devices such as ostomy bag, either disposable or of longer duration are usually used. These are expensive, particularly in countries like Bangladesh, and proper-sized ones are not always available. We have found an alternative for stoma care, betel leaf, which is suitable for Bangladeshis. We report the outcome of its use. After construction of stoma, at first zinc oxide paste was applied on the peristomal skin. A betel leaf with shiny, smooth surface outwards and rough surface inwards was put over the stoma with a hole made in the center according to the size of stoma. Another intact leaf covers the stomal opening. When bowel movement occurs, the overlying intact leaf was removed and the fecal matter was washed away from both. The leaves were reused after cleaning. Leaves were changed every 2 to 3 days. From June 1998 to December 2005, in the department of pediatric surgery, Chittagong Medical College and Hospital, Chittagong, Bangladesh, a total of 623 patients had exteriorization of bowel. Of this total, 495 stomas were cared for with betel leaves and 128 with ostomy bags. Of 623 children, 287 had sigmoid colostomy, 211 had transverse colostomy, 105 had ileostomy, and 20 had jejunostomy. Of the 495 children under betel leaf stoma care, 13 patients (2.6%) developed skin excoriation. There were no allergic reactions. Of the 128 patients using ostomy bag, 52 (40.65%) had skin excoriation. Twenty-four (18.75%) children developed some allergic reactions to adhesive. Monthly costs for betel leaves were 15 cents (10 BDT), whereas ostomy bags cost about US$24. In the care of stoma, betel leaves are cheap, easy to handle, nonirritant, and nonallergic.

Method for continuous measurement of export from a leaf

International Nuclear Information System (INIS)

Geiger, D.R.; Fondy, B.R.

1979-01-01

Export of labeled material derived by continuous photosynthesis in 14 CO 2 was monitored with a Geiger-Mueller detector positioned next to an exporting leaf blade. Rate of export of labeled material was calculated from the difference between rates of retention and net photosynthesis of labeled carbon for the observed leaf. Given certain conditions, including nearly constant distribution of labeled material among minor veins and various types of cells, count rate data for the source leaf can be coverted to rate of export of carbon. Changes in counting efficiency resulting from changes in leaf water status can be corrected for with data from a transducer which measures leaf thickness. Export data agreed with data obtained by monitoring the arrival of 14 C in the sink region; isolated leaves gave values near zero for export of labeled carbon from a given leaf on an intact plant. The technique detects changes in export with a resolution of 10 to 20 minutes

The influence of leaf anatomy on the internal light environment and photosynthetic electron transport rate: exploration with a new leaf ray tracing model.

Science.gov (United States)

Xiao, Yi; Tholen, Danny; Zhu, Xin-Guang

2016-11-01

Leaf photosynthesis is determined by biochemical properties and anatomical features. Here we developed a three-dimensional leaf model that can be used to evaluate the internal light environment of a leaf and its implications for whole-leaf electron transport rates (J). This model includes (i) the basic components of a leaf, such as the epidermis, palisade and spongy tissues, as well as the physical dimensions and arrangements of cell walls, vacuoles and chloroplasts; and (ii) an efficient forward ray-tracing algorithm, predicting the internal light environment for light of wavelengths between 400 and 2500nm. We studied the influence of leaf anatomy and ambient light on internal light conditions and J The results show that (i) different chloroplasts can experience drastically different light conditions, even when they are located at the same distance from the leaf surface; (ii) bundle sheath extensions, which are strips of parenchyma, collenchyma or sclerenchyma cells connecting the vascular bundles with the epidermis, can influence photosynthetic light-use efficiency of leaves; and (iii) chloroplast positioning can also influence the light-use efficiency of leaves. Mechanisms underlying leaf internal light heterogeneity and implications of the heterogeneity for photoprotection and for the convexity of the light response curves are discussed. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

ANXIOLYTIC ACTIVITY OF OCIMUM SANCTUM LEAF EXTRACT

OpenAIRE

Chattopadhyay, R.R.

1994-01-01

The anxiolytic activity of Ocimum sanctum leaf extract was studied in mice. O.sanctum leaf extract produced significant anxiolytic activity in plus – maze and open field behaviour test models. The effect was compared with diazepam, a standard antianxiety drug.

[Seasonal differences in the leaf hydraulic conductance of mature Acacia mangium in response to its leaf water use and photosynthesis].

Science.gov (United States)

Zhao, Ping; Sun, Gu-Chou; Ni, Guang-Yan; Zeng, Xiao-Ping

2013-01-01

In this study, measurements were made on the leaf water potential (psi1), stomatal conductance (g(s)), transpiration rate, leaf area index, and sapwood area of mature Acacia mangium, aimed to understand the relationships of the leaf hydraulic conductance (K1) with the leaf water use and photosynthetic characteristics of the A. mangium in wet season (May) and dry season (November). The ratio of sapwood area to leaf area (A(sp)/A(cl)) of the larger trees with an average height of 20 m and a diameter at breast height (DBH) of 0.26 m was 8.5% higher than that of the smaller trees with an average height of 14.5 m and a DBH of 0.19 m, suggesting that the larger trees had a higher water flux in their leaf xylem, which facilitated the water use of canopy leaf. The analysis on the vulnerability curve of the xylem showed that when the K1 decreased by 50%, the psi1 in wet season and dry season was -1.41 and -1.55 MPa, respectively, and the vulnerability of the xylem cavitation was higher in dry season than in wet season. The K1 peak value in wet season and dry season was 5.5 and 4.5 mmol x m(-2) x s(-1) x MPa(-1), and the maximum transpiration rate (T(r max)) was 3.6 and 1.8 mmol x m(-2) x s(-1), respectively. Both the K1 and T(r max), were obviously higher in wet season than in dry season. Within a day, the K1 and T(r), fluctuated many times, reflecting the reciprocated cycle of the xylem cavitation and refilling. The leaf stomatal closure occurred when the K1 declined over 50% or the psi1 reached -1.6 MPa. The g(s) would be maintained at a high level till the K1 declined over 50%. The correlation between the hydraulic conductance and photosynthetic rate was more significant in dry season than in wet season. The loss of leaf hydraulic conductance induced by seasonal change could be the causes of the decrease of T(r) and CO2 gas exchange.

[Revision to origin of northern Artemisia argyi in Compendium of Materia Medica (Bencao gangmu)].

Science.gov (United States)

Huang, Lu-qi; Qiu, Le

2014-12-01

The origin of northern Artemisia argyi recorded in Compendium of Materia Medica(Bencao gangmu) is Fudao(Chinese characters) in Tangyin county, While there is only Fudao(Chinese characters) instead of Fudao(Chinese characters). Whether indeed Fudao(Chinese characters) is Fudao(Chinese characters)? By reviewing the genuine evolution of A. argyi, doing textual research on Fudao(Chinese characters) and combing with field survey data of national census of Chinese Materia Medica resources, this paper concluded that the word Fudao(Chinese characters) firstly emerged in Figure Canon of Chinese Materia Medica(Bencao tujing) of Susong in Song dynasty and was applied in later generations, but the implication was not clear, then emerged both Tangyin and Fudao(Chinese characters) in Compendium of Materia Medica(Bencao gangmu). The place Fudao(Chinese characters) is one of the graves of Bianque, that existed from Shang and Zhou dynasty and never changed until now, the A. argyi of Tangyin was famous from the grave of Bianque in Fudao(Chinese characters), which could infer that Lishizhen considered Fudao (Chinese characters) was Fudao(Chinese characters) indeed, and the origin of northern A. argyi was Fudao(Chinese characters) in Tangyin county.

Understanding of Leaf Development—the Science of Complexity

Directory of Open Access Journals (Sweden)

Robert Malinowski

2013-06-01

Full Text Available The leaf is the major organ involved in light perception and conversion of solar energy into organic carbon. In order to adapt to different natural habitats, plants have developed a variety of leaf forms, ranging from simple to compound, with various forms of dissection. Due to the enormous cellular complexity of leaves, understanding the mechanisms regulating development of these organs is difficult. In recent years there has been a dramatic increase in the use of technically advanced imaging techniques and computational modeling in studies of leaf development. Additionally, molecular tools for manipulation of morphogenesis were successfully used for in planta verification of developmental models. Results of these interdisciplinary studies show that global growth patterns influencing final leaf form are generated by cooperative action of genetic, biochemical, and biomechanical inputs. This review summarizes recent progress in integrative studies on leaf development and illustrates how intrinsic features of leaves (including their cellular complexity influence the choice of experimental approach.

Does leaf chemistry differentially affect breakdown in tropical versus temperate streams? Importance of standardized analytical techniques to measure leaf chemistry

Science.gov (United States)

Marcelo Ardon; Catherine M. Pringle; Susan L. Eggert

2009-01-01

Comparisons of the effects of leaf litter chemistry on leaf breakdown rates in tropical vs temperate streams are hindered by incompatibility among studies and across sites of analytical methods used to...

Comparison of antimalarial activity of Artemisia turanica extract with current drugs in vivo.

Science.gov (United States)

Taherkhani, Mahboubeh; Rustaiyan, Abdolhossein; Nahrevanian, Hossein; Naeimi, Sabah; Taherkhani, Tofigh

2013-03-01

The purpose of this study was to compare antimalarial activity of Artemisia turanica Krasch as Iranian flora with current antimalarial drugs against Plasmodium berghei in vivo in mice. Air-dried aerial parts of Iranian flora A. turanica were collected from Khorasan, northeastern Iran, extracted with Et2O/MeOH/Petrol and defatted. Toxicity of herbal extracts was assessed on male NMRI mice, and their antimalarial efficacy was compared with antimalarial drugs [artemether, chloroquine and sulfadoxinepyrimethamine (Fansidar)] on infected P. berghei animals. All the groups were investigated for parasitaemia, body weight, hepatomegaly, splenomegaly and anemia. The significance of differences was determined by Analysis of Variances (ANOVA) and Student's t-test using Graph Pad Prism software. The inhibitory effects of A. turanica extract on early decline of P. berghei parasitaemia highlights its antimalarial activity, however, this effect no longer can be observed in the late infection. This may be due to the metabolic process of A. turanica crude extract by mice and reduction of its concentration in the body. Crude extract of A. turanica represented its antisymptomatic effects by stabilization of body, liver and spleen weights. This study confirmed antimalarial effects of A. turanica extracts against murine malaria in vivo during early infection, however, there are more benefits on pathophysiological symptoms by this medication.

TLC-direct bioautography for determination of antibacterial activity of Artemisia adamsii essential oil.

Science.gov (United States)

Horváth, Györgyi; Acs, Kamilla; Kocsis, Béla

2013-01-01

The aim of the present study was the chemical characterization of the essential oil of a Mongolian medicinal plant, Artemisia adamsii Besser, and the investigation of the antibacterial effect of its oil on different human pathogenic bacteria (Staphylococcus aureus, methicillin-resistant S. aureus, and S. epidermidis). The chemical composition of the oil was established by GC and GC/MS. Direct bioautography was used for detecting the antibacterial activity of the essential oil. The result of GC experiments showed that a-thujone was the main component (64.4%) of the oil, while the amount of beta-thujone was 7.1%. 1,8-Cineole seemed to be the other relevant component (15.2%). The antibacterial activity of the A. adamsii essential oil against all three investigated bacteria was observed in the bioautographic system, but this effect was not proportional to the concentrations of a- or beta-thujone; therefore, from a microbiological aspect, thujone content does not determine the medicinal value of this oil. On the whole, the combination of TLC separation with biological detection is an appropriate method for evaluating multicomponent and hydrophobic plant extracts, for instance, essential oils, and it provides more reliable results than traditional microbiological methods (e.g., disc diffusion and agar plate techniques).

The application of biotic elicitor on Artemisia annua L. to increase artemisinin content

Science.gov (United States)

Darwati, I.; Manohara, D.; Rohimatun; Nurhayati, H.

2018-01-01

Artemisinin-based Combination Therapy (ACT) has been recommended by WHO as an alternative to treat malaria overcoming drug resistance. The secondary metabolic products in plants, including artemisinin, can be increased by utilizing biotic elicitor from fungi. The research was conducted in Gunung Putri Research Installation, Cipanas, West Java from 2010 to 2011. Phytophthora sp. from eggplant and Colletotrichum sp. from Artemisia annua were applied as biotic elicitor. The types of biotic elicitor applied to the plants were 1) the medium of potato dextrose broth were inoculated with fungi and harvested after 10 days (filtrate), 2) powdery mycelium of both fungi. There were 16 treatments: control negative, control positive (uninoculated medium) 1%, 2%, 3% (v/v)], Phytophthora sp. filtrate [1, 2% and 3% (v/v)], Colletotrichum sp. filtrate [1, 2% and 3% (v/v)], Phytophthora sp. mycelium [1%, 2% and 3% (w/v)], Colletotrichum sp mycelium [1%, 2% and 3% (w/v)]. The elicitor application increased plant production by 26.21% and artemisinin yield by 72% compared to control. Furthermore, the artemisinin production of the plants treated with medium inoculated with 2% filtrate of Phytophthora sp (FP2) (25.19 kg/ha) and 1% powdery mycelium of Colletotrichum sp (MC1) (26.42 kg/ha) were higher than control (K) (11.17 kg/ha).

The effect of air pollution and other environmental stressors on leaf fluctuating asymmetry and specific leaf area of Salix alba L

Energy Technology Data Exchange (ETDEWEB)

Wuytack, Tatiana, E-mail: tatiana.wuytack@ua.ac.be [Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Wuyts, Karen, E-mail: karen.wuyts@ugent.be [Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Gontrode (Melle) (Belgium); Van Dongen, Stefan, E-mail: stefan.vandongen@ua.ac.be [Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Baeten, Lander, E-mail: lander.baeten@ugent.be [Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Gontrode (Melle) (Belgium); Kardel, Fatemeh, E-mail: fatemeh.kardel@ua.ac.be [Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Verheyen, Kris, E-mail: kris.verheyen@ugent.be [Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Gontrode, Melle (Belgium); Samson, Roeland, E-mail: roeland.samson@ua.ac.be [Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

2011-10-15

We aimed at evaluating the effect of low-level air pollution on leaf area fluctuating asymmetry (FAA) and specific leaf area (SLA) of Salix alba L., taking into account other environmental factors. Cuttings were grown in standardized conditions in the near vicinity of air quality measuring stations in Belgium. Variability of SLA and FAA between measuring stations explained 83% and 7.26%, respectively, of the total variability. FAA was not influenced by air pollution or environmental factors such as shading, herbivory, air temperature and humidity. SLA was increased by an increase in shadow, while NO{sub x} and O{sub 3} concentrations had only a marginal influence. The influence of SO{sub 2} concentration was negligible. Although our data analysis suggests a relationship between SLA and NO{sub x}/O{sub 3} concentration, the absence of a straightforward relationship between FAA and SLA and air pollution still questions the usefulness of these bio-indicators for monitoring air pollution. - Highlights: > Leaf characteristics of white willow as possible bio-indicators for air quality. > Fluctuating asymmetry is not a good bio-indicator for monitoring the air quality. > Shadow increases specific leaf area. > NO{sub x} and O{sub 3} change specific leaf area of white willow. - Specific leaf area of S. alba increased with increasing shade and, in less extent, with increasing NO{sub x} and decreasing O{sub 3} concentration, while leaf asymmetry did not respond to air pollution

The effect of air pollution and other environmental stressors on leaf fluctuating asymmetry and specific leaf area of Salix alba L

International Nuclear Information System (INIS)

Wuytack, Tatiana; Wuyts, Karen; Van Dongen, Stefan; Baeten, Lander; Kardel, Fatemeh; Verheyen, Kris; Samson, Roeland

2011-01-01

We aimed at evaluating the effect of low-level air pollution on leaf area fluctuating asymmetry (FAA) and specific leaf area (SLA) of Salix alba L., taking into account other environmental factors. Cuttings were grown in standardized conditions in the near vicinity of air quality measuring stations in Belgium. Variability of SLA and FAA between measuring stations explained 83% and 7.26%, respectively, of the total variability. FAA was not influenced by air pollution or environmental factors such as shading, herbivory, air temperature and humidity. SLA was increased by an increase in shadow, while NO x and O 3 concentrations had only a marginal influence. The influence of SO 2 concentration was negligible. Although our data analysis suggests a relationship between SLA and NO x /O 3 concentration, the absence of a straightforward relationship between FAA and SLA and air pollution still questions the usefulness of these bio-indicators for monitoring air pollution. - Highlights: → Leaf characteristics of white willow as possible bio-indicators for air quality. → Fluctuating asymmetry is not a good bio-indicator for monitoring the air quality. → Shadow increases specific leaf area. → NO x and O 3 change specific leaf area of white willow. - Specific leaf area of S. alba increased with increasing shade and, in less extent, with increasing NO x and decreasing O 3 concentration, while leaf asymmetry did not respond to air pollution

Use of NAP gene to manipulate leaf senescence in plants

Science.gov (United States)

Gan, Susheng; Guo, Yongfeng

2013-04-16

The present invention discloses transgenic plants having an altered level of NAP protein compared to that of a non-transgenic plant, where the transgenic plants display an altered leaf senescence phenotype relative to a non-transgenic plant, as well as mutant plants comprising an inactivated NAP gene, where mutant plants display a delayed leaf senescence phenotype compared to that of a non-mutant plant. The present invention also discloses methods for delaying leaf senescence in a plant, as well as methods of making a mutant plant having a decreased level of NAP protein compared to that of a non-mutant plant, where the mutant plant displays a delayed leaf senescence phenotype relative to a non-mutant plant. Methods for causing precocious leaf senescence or promoting leaf senescence in a plant are also disclosed. Also disclosed are methods of identifying a candidate plant suitable for breeding that displays a delayed leaf senescence and/or enhanced yield phenotype.

A better way of representing stem area index in two-big-leaf models: the application and impact on canopy integration of leaf nitrogen content

Science.gov (United States)

Chen, M.; Butler, E. E.; Wythers, K. R.; Kattge, J.; Ricciuto, D. M.; Thornton, P. E.; Atkin, O. K.; Flores-Moreno, H.; Reich, P. B.

2017-12-01

In order to better estimate the carbon budget of the globe, accurately simulating gross primary productivity (GPP) in earth system models is critical. When upscaling leaf level photosynthesis to the canopy, climate models uses different big-leaf schemes. About half of the state-of-the-art earth system models use a "two-big-leaf" scheme that partitions canopies into direct and diffusively illuminated fractions to reduce high bias of GPP simulated by one-big-leaf models. Some two-big-leaf models, such as ACME (identical in this respect to CLM 4.5) add leaf area index (LAI) and stem area index (SAI) together when calculating canopy radiation transfer. This treatment, however, will result in higher fraction of sunlit leaves. It will also lead to an artificial overestimation of canopy nitrogen content. Here we introduce a new algorithm of simulating SAI in a two-big-leaf model. The new algorithm reduced the sunlit leave fraction of the canopy and conserved the nitrogen content from leaf to canopy level. The lower fraction of sunlit leaves reduced global GPP especially in tropical area. Compared to the default model, for the past 100 years (1909-2009), the averaged global annual GPP is lowered by 4.11 PgC year-1 using this new algorithm.

Timing and duration of autumn leaf development in Sweden

Science.gov (United States)

Bolmgren, Kjell

2014-05-01

The growing season is changing in both ends and autumn phases seem to be responding in more diverse ways than spring events. Indeed, we know little about autumn leaf phenological strategies and how they are correlated with fitness components or ecosystem properties, and how they vary between species and over bioclimatic gradients. In this study more than 10 000 students were involved in observing autumn leaf development at 378 sites all over Sweden (55-68°N). They followed an image based observation protocol classifying autumn leaf development into five levels, from summer green (level 0) to 100% autumn leaf colored (level 4) canopy. In total, they submitted almost 12 000 observations between August 9 and November 15. 75% of the observations were made on the common species of Populus tremula, Betula pendula/pubescens and Sorbus aucuparia. The expected (negative) correlation between latitude and start of leaf senescence (level 2) was found in Populus and Betula, but not in Sorbus. The duration of the leaf senescence period, defined as the period between 1/3 (level 2) and 100% (level 4) of the canopy autumn leaf colored, was negatively correlated with latitude in Populus and Betula, but not in Sorbus. There was also a strong (negative) correlation of the start (level 2) and the duration of the leaf senescence in the early senescing Sorbus and Betula, while this effect was weaker in the late senescing Populus.

Leaf size indices and structure of the peat swamp forest

Directory of Open Access Journals (Sweden)

L.G. Aribal

2017-12-01

Full Text Available Leaf size indices of the tree species in the peatland of Agusan del Sur in Mindanao in Philippines was examined to deduce the variation of forest structure and observed forest zonation.  Using raunkiaer and webb’s leaf size classification, the leaf morphometrics of seven tree species consistently found on the established sampling plots were determined.  The species includes Ternstroemia philippinensis Merr., Polyscias aherniana Merr. Lowry and G.M. Plunkett, Calophyllum sclerophyllum Vesque, Fagraea racemosa Jack, Ilex cymosa Blume, Syzygium tenuirame (Miq. Merr. and Tristaniopsis micrantha Merr. Peter G.Wilson and J.T.Waterh.The LSI were correlated against the variables of the peat physico-chemical properties (such as bulk density, acrotelm thickness, peat depth, total organic carbon, nitrogen, phosphorus, and potassium, pH; water (pH, ammonium, nitrate, phosphate; and leaf tissue elements (nitrogen, phosphorus and potassium.  Result showed a decreasing leaf size indices and a three leaf size category consisting of mesophyllous, mesophyllous-notophyllous and microphyllous were observed which corresponds to the structure of vegetation i.e., from the tall-pole forest having the biggest average leaf area of 6,142.29 mm2 to the pygmy forest with average leaf area of 1,670.10 mm2.  Such decreased leaf size indices were strongly correlated to soil nitrogen, acrotelm thickness, peat depth, phosphate in water, nitrogen and phosphorus in the plant tissue.

Evaluation of two methods of predicting MLC leaf positions using EPID measurements

International Nuclear Information System (INIS)

Parent, Laure; Seco, Joao; Evans, Phil M.; Dance, David R.; Fielding, Andrew

2006-01-01

In intensity modulated radiation treatments (IMRT), the position of the field edges and the modulation within the beam are often achieved with a multileaf collimator (MLC). During the MLC calibration process, due to the finite accuracy of leaf position measurements, a systematic error may be introduced to leaf positions. Thereafter leaf positions of the MLC depend on the systematic error introduced on each leaf during MLC calibration and on the accuracy of the leaf position control system (random errors). This study presents and evaluates two methods to predict the systematic errors on the leaf positions introduced during the MLC calibration. The two presented methods are based on a series of electronic portal imaging device (EPID) measurements. A comparison with film measurements showed that the EPID could be used to measure leaf positions without introducing any bias. The first method, referred to as the 'central leaf method', is based on the method currently used at this center for MLC leaf calibration. It mimics the manner in which leaf calibration parameters are specified in the MLC control system and consequently is also used by other centers. The second method, a new method proposed by the authors and referred to as the ''individual leaf method,'' involves the measurement of two positions for each leaf (-5 and +15 cm) and the interpolation and extrapolation from these two points to any other given position. The central leaf method and the individual leaf method predicted leaf positions at prescribed positions of -11, 0, 5, and 10 cm within 2.3 and 1.0 mm, respectively, with a standard deviation (SD) of 0.3 and 0.2 mm, respectively. The individual leaf method provided a better prediction of the leaf positions than the central leaf method. Reproducibility tests for leaf positions of -5 and +15 cm were performed. The reproducibility was within 0.4 mm on the same day and 0.4 mm six weeks later (1 SD). Measurements at gantry angles of 0 deg., 90 deg., and 270 deg

Climatic Controls on Leaf Nitrogen Content and Implications for Biochemical Modeling.

Science.gov (United States)

Tcherednichenko, I. A.; White, M.; Bastidas, L.

2007-12-01

Leaf nitrogen (N) content, expressed as percent total nitrogen per unit of leaf dry mass, is a widely used parameter in biochemical modeling, due mainly to its role as a potentially limiting factor for photosynthesis. The amount of nitrogen, however, does not occur in a fixed amount in every leaf, but rather varies continuously with the leaf life cycle, in constant response to soil-root-stem-leaf-climate interactions and demand for growth. Moreover, while broad data on leaf N has become available it is normally measured under ambient conditions with consequent difficulty for distinguishing between genetic and time specific environmental effects. In the present work we: 1) Investigate the theoretical variation of leaf mass, specific heat capacity and leaf thickness of full sun-expanded leaves as a regulatory mechanism to ensure thermal survival along with long-term climatic radiation/temperature gradient; and discuss nitrogen and carbon controls on leaf thickness. 2) Based on possible states of partition between nitrogenous and non-nitrogenous components of a leaf we further derive probability density functions (PDFs) of nitrogen and carbon content and assess the effect of water and nutrient uptake on the PDFs. 3) Translate the results to spatially explicit representation over the conterminous USA at 1 km spatial resolution by providing maximum potential values of leaf N of fully expanded leaf optimally suited for long term climatic averages values and soils conditions. Implications for potential presence of inherently slow/fast growing species are discussed along with suitability of results for use by biochemical models.

Trade-offs between seed and leaf size (seed-phytomer-leaf theory): functional glue linking regenerative with life history strategies … and taxonomy with ecology?

Science.gov (United States)

Hodgson, John G; Santini, Bianca A; Montserrat Marti, Gabriel; Royo Pla, Ferran; Jones, Glynis; Bogaard, Amy; Charles, Mike; Font, Xavier; Ater, Mohammed; Taleb, Abdelkader; Poschlod, Peter; Hmimsa, Younes; Palmer, Carol; Wilson, Peter J; Band, Stuart R; Styring, Amy; Diffey, Charlotte; Green, Laura; Nitsch, Erika; Stroud, Elizabeth; Romo-Díez, Angel; de Torres Espuny, Lluis; Warham, Gemma

2017-11-10

While the 'worldwide leaf economics spectrum' (Wright IJ, Reich PB, Westoby M, et al. 2004. The worldwide leaf economics spectrum. Nature : 821-827) defines mineral nutrient relationships in plants, no unifying functional consensus links size attributes. Here, the focus is upon leaf size, a much-studied plant trait that scales positively with habitat quality and components of plant size. The objective is to show that this wide range of relationships is explicable in terms of a seed-phytomer-leaf (SPL) theoretical model defining leaf size in terms of trade-offs involving the size, growth rate and number of the building blocks (phytomers) of which the young shoot is constructed. Functional data for 2400+ species and English and Spanish vegetation surveys were used to explore interrelationships between leaf area, leaf width, canopy height, seed mass and leaf dry matter content (LDMC). Leaf area was a consistent function of canopy height, LDMC and seed mass. Additionally, size traits are partially uncoupled. First, broad laminas help confer competitive exclusion while morphologically large leaves can, through dissection, be functionally small. Secondly, leaf size scales positively with plant size but many of the largest-leaved species are of medium height with basally supported leaves. Thirdly, photosynthetic stems may represent a functionally viable alternative to 'small seeds + large leaves' in disturbed, fertile habitats and 'large seeds + small leaves' in infertile ones. Although key elements defining the juvenile growth phase remain unmeasured, our results broadly support SPL theory in that phytometer and leaf size are a product of the size of the initial shoot meristem (≅ seed mass) and the duration and quality of juvenile growth. These allometrically constrained traits combine to confer ecological specialization on individual species. Equally, they appear conservatively expressed within major taxa. Thus, 'evolutionary canalization' sensu Stebbins (Stebbins GL

Antioxidant Activity and Cytotoxicity of the Leaf and Bark Extracts of ...

African Journals Online (AJOL)

Purpose: To investigate the antioxidant potential and cytotoxicity of the leaf and bark extracts of Tarchonanathus campharatus.. Methods: The antioxidant activity of the aqueous leaf extract (Aq LF), methanol leaf extract (MET LF), dichloromethane leaf extract (DCM LF), methanol bark extract (MET BK), dichloromethane bark ...

Estimating leaf photosynthetic pigments information by stepwise multiple linear regression analysis and a leaf optical model

Science.gov (United States)

Liu, Pudong; Shi, Runhe; Wang, Hong; Bai, Kaixu; Gao, Wei

2014-10-01

Leaf pigments are key elements for plant photosynthesis and growth. Traditional manual sampling of these pigments is labor-intensive and costly, which also has the difficulty in capturing their temporal and spatial characteristics. The aim of this work is to estimate photosynthetic pigments at large scale by remote sensing. For this purpose, inverse model were proposed with the aid of stepwise multiple linear regression (SMLR) analysis. Furthermore, a leaf radiative transfer model (i.e. PROSPECT model) was employed to simulate the leaf reflectance where wavelength varies from 400 to 780 nm at 1 nm interval, and then these values were treated as the data from remote sensing observations. Meanwhile, simulated chlorophyll concentration (Cab), carotenoid concentration (Car) and their ratio (Cab/Car) were taken as target to build the regression model respectively. In this study, a total of 4000 samples were simulated via PROSPECT with different Cab, Car and leaf mesophyll structures as 70% of these samples were applied for training while the last 30% for model validation. Reflectance (r) and its mathematic transformations (1/r and log (1/r)) were all employed to build regression model respectively. Results showed fair agreements between pigments and simulated reflectance with all adjusted coefficients of determination (R2) larger than 0.8 as 6 wavebands were selected to build the SMLR model. The largest value of R2 for Cab, Car and Cab/Car are 0.8845, 0.876 and 0.8765, respectively. Meanwhile, mathematic transformations of reflectance showed little influence on regression accuracy. We concluded that it was feasible to estimate the chlorophyll and carotenoids and their ratio based on statistical model with leaf reflectance data.

Optimal leaf positions for chlorophyll meter measurement in rice

Directory of Open Access Journals (Sweden)

Zhaofeng eYuan

2016-05-01

Full Text Available The Soil Plant Analysis Development (SPAD chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.. A flatbed color scanner was used to map the dynamic chlorophyll distribution and irregular leaf shapes. Calculus algorithm was adopted to estimate the potential positions for SPAD meter measurement along the leaf blade. Data generated by the flatbed color scanner and SPAD meter were analysed simultaneously. The results suggested that a position 2/3 of the distance from the leaf base to the apex (2/3 position could represent the chlorophyll content of the entire leaf blade, as indicated by the relatively low variance of measurements at that positon. SPAD values based on di-positional leaves and the extracted chlorophyll a and b contents were compared. This comparison showed that the 2/3 position on the lower leaves tended to be more sensitive to changes in chlorophyll content. Finally, the 2/3 position and average SPAD values of the fourth fully expanded leaf from the top were compared with leaf nitrogen concentration. The results showed the 2/3 position on that leaf was most suitable for predicting the nitrogen status of rice. Based on these results, we recommend making SPAD measurements at the 2/3 position on the fourth fully expanded leaf from the top. The coupling of dynamic chlorophyll distribution and irregular leaf shapes information can provide a promising approach for the calibration of SPAD meter measurement, which can further benefit the in situ nitrogen management by providing reliable estimation of crops nitrogen nutrition status.

Leaf area prediction models for Tsuga canadensis in Maine

Science.gov (United States)

Laura S. Kenefic; R.S. Seymour

1999-01-01

Tsuga canadensis (L.) Carr. (eastern hemlock) is a common species throughout the Acadian forest. Studies of leaf area and growth efficiency in this forest type have been limited by the lack of equations to predict leaf area of this species. We found that sapwood area was an effective leaf area surrogate in T. canadensis, though...

Simulated Acid Rain-induced Alterations in Flowering, Leaf ...

African Journals Online (AJOL)

Evaluation of SAR effects on budding, flowering, leaf abscission and pollen development revealed that ... Keywords: Simulated acid rain, Helianthus annuus, flowering, leaf abscission, pollen germination, sunflower. ... HOW TO USE AJOL.

Growth and artemisinin content of artemisia Annua L. As a result of gamma irradiation on shoot culture

International Nuclear Information System (INIS)

Tri Muji Ermayanti; Erwin Al Hafiizh; Andri Fadillah Martin; Arthur A Lelono; Wiguna Rahman

2016-01-01

Artemisinin is the main compound produced by Artemisia annua is used as antimalarial drug. Many research have been conducted in order to increase artemisinin content in A. annua so that it can be produced economically. In several plants, mutation can be induced by Gamma irradiation to increase their secondary metabolite production. The aim of this research was to investigate the growth and artemisinin content of A. annua after Gamma irradiation. Irradiation was conducted using in vitro shoot tips with 5-50 Gy. Survival rate, growth of shoot culture, ploidy level confirmation, acclimatization, growth of plants in the field and artemisinin content were recorded. The results showed that LD_5_0 of A. annua was 37 Gy, therefore, shoots only grew in the control environment in the laboratory, their growth in the field was inhibited. Irradiation with 50 Gy, shoots only grew for 8 weeks, and died afterwards. Irradiation dose affected on growth of plants in the field as well as their artemisinin content. (author)

A leaf gas exchange model that accounts for intra-canopy variability by considering leaf nitrogen content and local acclimation to radiation in grapevine (Vitis vinifera L.).

Science.gov (United States)

Prieto, Jorge A; Louarn, Gaëtan; Perez Peña, Jorge; Ojeda, Hernán; Simonneau, Thierry; Lebon, Eric

2012-07-01

Understanding the distribution of gas exchange within a plant is a prerequisite for scaling up from leaves to canopies. We evaluated whether leaf traits were reliable predictors of the effects of leaf ageing and leaf irradiance on leaf photosynthetic capacity (V(cmax) , J(max) ) in field-grown vines (Vitis vinifera L). Simultaneously, we measured gas exchange, leaf mass per area (LMA) and nitrogen content (N(m) ) of leaves at different positions within the canopy and at different phenological stages. Daily mean leaf irradiance cumulated over 10 d (PPFD(10) ) was obtained by 3D modelling of the canopy structure. N(m) decreased over the season in parallel to leaf ageing while LMA was mainly affected by leaf position. PPFD(10) explained 66, 28 and 73% of the variation of LMA, N(m) and nitrogen content per area (N(a) ), respectively. Nitrogen content per unit area (N(a) = LMA × N(m) ) was the best predictor of the intra-canopy variability of leaf photosynthetic capacity. Finally, we developed a classical photosynthesis-stomatal conductance submodel and by introducing N(a) as an input, the model accurately simulated the daily pattern of gas exchange for leaves at different positions in the canopy and at different phenological stages during the season. © 2012 Blackwell Publishing Ltd.

Optimal leaf sequencing with elimination of tongue-and-groove underdosage

Energy Technology Data Exchange (ETDEWEB)

Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)

2004-02-07

The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

Optimal leaf sequencing with elimination of tongue-and-groove underdosage

International Nuclear Information System (INIS)

Kamath, Srijit; Sahni, Sartaj; Palta, Jatinder; Ranka, Sanjay; Li, Jonathan

2004-01-01

The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

Do Aphids Alter Leaf Surface Temperature Patterns During Early Infestation?

Directory of Open Access Journals (Sweden)

Thomas Cahon

2018-03-01

Full Text Available Arthropods at the surface of plants live in particular microclimatic conditions that can differ from atmospheric conditions. The temperature of plant leaves can deviate from air temperature, and leaf temperature influences the eco-physiology of small insects. The activity of insects feeding on leaf tissues, may, however, induce changes in leaf surface temperatures, but this effect was only rarely demonstrated. Using thermography analysis of leaf surfaces under controlled environmental conditions, we quantified the impact of presence of apple green aphids on the temperature distribution of apple leaves during early infestation. Aphids induced a slight change in leaf surface temperature patterns after only three days of infestation, mostly due to the effect of aphids on the maximal temperature that can be found at the leaf surface. Aphids may induce stomatal closure, leading to a lower transpiration rate. This effect was local since aphids modified the configuration of the temperature distribution over leaf surfaces. Aphids were positioned at temperatures near the maximal leaf surface temperatures, thus potentially experiencing the thermal changes. The feedback effect of feeding activity by insects on their host plant can be important and should be quantified to better predict the response of phytophagous insects to environmental changes.

Leaf micromorphology of some Phyllanthus L. species (Phyllanthaceae)

Energy Technology Data Exchange (ETDEWEB)

Solihani, N. S., E-mail: noorsolihani@gmail.com; Noraini, T., E-mail: norainitalip@gmail.com [School of Environmental and Natural Resource Sciences Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Azahana, A., E-mail: bell-azahana@yahoo.com [Department of Plant Science, Kulliyyah of Science, International Islamic University Malaysia, Kuantan Campus, Kuantan, Pahang (Malaysia); Nordahlia, A. S., E-mail: nordahlia@frim.gov.my [Forest Research Institute of Malaysia, 52109 Kepong, Selangor (Malaysia)

2015-09-25

Comparative leaf micromorphological study was conducted of five chosen Phyllanthus L. (Phyllanthaceae) species, namely P. acidus L., P. elegans Wall. ex Müll. Arg., P. emblica L., P. urinaria L. and P. pulcher Wall. ex Müll. Arg. The objective of this study is to identify the leaf micromorphological characteristics that can be used in species identification. The procedures involve examination under scanning electron microscope. Findings of this study have demonstrated variations in the leaf micromorphological characteristics such as in the types of waxes present on adaxial and abaxial epidermis surfaces, in the stomata and types of trichome. Common character present in all species studied are the presence of a thin film layer and buttress-like waxes on epidermal leaf surfaces. Diagnostics characters found in this study are the presence of papilla in P. elegens, amphistomatic stomata in P. urinaria and flaky waxes in P. pulcher. The result of this study has shown that leaf micromorphological characters have some taxonomic significance and can be used in identification of species in the genus Phyllanthus.

Leaf absorbance and photosynthesis

Science.gov (United States)

Schurer, Kees

1994-01-01

The absorption spectrum of a leaf is often thought to contain some clues to the photosynthetic action spectrum of chlorophyll. Of course, absorption of photons is needed for photosynthesis, but the reverse, photosynthesis when there is absorption, is not necessarily true. As a check on the existence of absorption limits we measured spectra for a few different leaves. Two techniques for measuring absorption have been used, viz. the separate determination of the diffuse reflectance and the diffuse transmittance with the leaf at a port of an integrating sphere and the direct determination of the non-absorbed fraction with the leaf in the sphere. In a cross-check both methods yielded the same results for the absorption spectrum. The spectrum of a Fuchsia leaf, covering the short-wave region from 350 to 2500 nm, shows a high absorption in UV, blue and red, the well known dip in the green and a steep fall-off at 700 nm. Absorption drops to virtually zero in the near infrared, with subsequent absorptions, corresponding to the water absorption bands. In more detailed spectra, taken at 5 nm intervals with a 5 nm bandwidth, differences in chlorophyll content show in the different depths of the dip around 550 nm and in a small shift of the absorption edge at 700 nm. Spectra for Geranium (Pelargonium zonale) and Hibiscus (with a higher chlorophyll content) show that the upper limit for photosynthesis can not be much above 700 nm. No evidence, however, is to be seen of a lower limit for photosynthesis and, in fact, some experiments down to 300 nm still did not show a decrease of the absorption although it is well recognized that no photosynthesis results with 300 nm wavelengths.

Antibacterial Activity of Vernonia amygdalina Leaf Extracts against ...

African Journals Online (AJOL)

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(Bitter leaf), Allium sativum (Garlic), O. gratissimum. (Scent leaf) ... complex active components that are useful ... hydroxide was added. .... KEY: CPX-Ciprofloxacin, Ro-Rocephin, St-Streptomycin, AU-Augmentin, SXT-Septrin, SP- Sparfloxacin, ...

Estimation of leaf area in tropical maize

NARCIS (Netherlands)

Elings, A.

2000-01-01

Leaf area development of six tropical maize cultivars grown in 1995 and 1996 in several tropical environments in Mexico (both favourable and moisture-and N-limited) was observed and analysed. First, the validity of a bell-shaped curve describing the area of individual leaves as a function of leaf

Frost and leaf-size gradients in forests: global patterns and experimental evidence.

Science.gov (United States)

Lusk, Christopher H; Clearwater, Michael J; Laughlin, Daniel C; Harrison, Sandy P; Prentice, Iain Colin; Nordenstahl, Marisa; Smith, Benjamin

2018-05-16

Explanations of leaf size variation commonly focus on water availability, yet leaf size also varies with latitude and elevation in environments where water is not strongly limiting. We provide the first conclusive test of a prediction of leaf energy balance theory that may explain this pattern: large leaves are more vulnerable to night-time chilling, because their thick boundary layers impede convective exchange with the surrounding air. Seedlings of 15 New Zealand evergreens spanning 12-fold variation in leaf width were exposed to clear night skies, and leaf temperatures were measured with thermocouples. We then used a global dataset to assess several climate variables as predictors of leaf size in forest assemblages. Leaf minus air temperature was strongly correlated with leaf width, ranging from -0.9 to -3.2°C in the smallest- and largest-leaved species, respectively. Mean annual temperature and frost-free period were good predictors of evergreen angiosperm leaf size in forest assemblages, but no climate variable predicted deciduous leaf size. Although winter deciduousness makes large leaves possible in strongly seasonal climates, large-leaved evergreens are largely confined to frost-free climates because of their susceptibility to radiative cooling. Evergreen leaf size data can therefore be used to enhance vegetation models, and to infer palaeotemperatures from fossil leaf assemblages. © 2018 The Authors New Phytologist © 2018 New Phytologist Trust.

TALE and Shape: How to Make a Leaf Different.

Science.gov (United States)

Di Giacomo, Elisabetta; Iannelli, Maria Adelaide; Frugis, Giovanna

2013-05-06

The Three Amino acid Loop Extension (TALE) proteins constitute an ancestral superclass of homeodomain transcription factors conserved in animals, plants and fungi. In plants they comprise two classes, KNOTTED1-LIKE homeobox (KNOX) and BEL1-like homeobox (BLH or BELL, hereafter referred to as BLH), which are involved in shoot apical meristem (SAM) function, as well as in the determination and morphological development of leaves, stems and inflorescences. Selective protein-protein interactions between KNOXs and BLHs affect heterodimer subcellular localization and target affinity. KNOXs exert their roles by maintaining a proper balance between undifferentiated and differentiated cell state through the modulation of multiple hormonal pathways. A pivotal function of KNOX in evolutionary diversification of leaf morphology has been assessed. In the SAM of both simple- and compound-leafed seed species, downregulation of most class 1 KNOX (KNOX1) genes marks the sites of leaf primordia initiation. However, KNOX1 expression is re-established during leaf primordia development of compound-leafed species to maintain transient indeterminacy and morphogenetic activity at the leaf margins. Despite the increasing knowledge available about KNOX1 protein function in plant development, a comprehensive view on their downstream effectors remains elusive. This review highlights the role of TALE proteins in leaf initiation and morphological plasticity with a focus on recent advances in the identification of downstream target genes and pathways.

Simple models for predicting leaf area of mango (Mangifera indica L.

Directory of Open Access Journals (Sweden)

Maryam Ghoreishi

2012-01-01

Full Text Available Mango (Mangifera indica L., one of the most popular tropical fruits, is cultivated in a considerable part of southern Iran. Leaf area is a valuable parameter in mango research, especially plant physiological and nutrition field. Most of available methods for estimating plant leaf area are difficult to apply, expensive and destructive which could in turn destroy the canopy and consequently make it difficult to perform further tests on the same plant. Therefore, a non-destructive method which is simple, inexpensive, and could yield an accurate estimation of leaf area will be a great benefit to researchers. A regression analysis was performed in order to determine the relationship between the leaf area and leaf width, leaf length, dry and fresh weight. For this purpose 50 mango seedlings of local selections were randomly took from a nursery in the Hormozgan province, and different parts of plants were separated in laboratory. Leaf area was measured by different method included leaf area meter, planimeter, ruler (length and width and the fresh and dry weight of leaves were also measured. The best regression models were statistically selected using Determination Coefficient, Maximum Error, Model Efficiency, Root Mean Square Error and Coefficient of Residual Mass. Overall, based on regression equation, a satisfactory estimation of leaf area was obtained by measuring the non-destructive parameters, i.e. number of leaf per seedling, length of the longest and width of widest leaf (R2 = 0.88 and also destructive parameters, i.e. dry weight (R2 = 0.94 and fresh weight (R2= 0.94 of leaves.

Effects of leaf age within growth stages of pepper and sorghum plants on leaf thickness, water, chlorophyll, and light reflectance. [in spectral vegetation discrimination

Science.gov (United States)

Gausman, H. W.; Cardenas, R.; Berumen, A.

1974-01-01

Pepper and sorghum plants (characterized by porous and compact leaf mesophylls, respectively) were used to study the influence of leaf age on light reflectance. Measurements were limited to the upper five nodal positions within each growth stage, since upper leaves make up most of the reflectance surfaces remotely sensed. The increase in leaf thickness and water content with increasing leaf age was taken into consideration, since each of these factors affects the reflectance as well as the selection of spectral wavelength intervals for optimum discrimination of vegetation.

Bioactivities and Chemical Constituents of Essential Oil Extracted from Artemisia anethoides Against Two Stored Product Insects.

Science.gov (United States)

Liang, Jun-Yu; Wang, Wen-Ting; Zheng, Yan-Fei; Zhang, Di; Wang, Jun-Long; Guo, Shan-Shan; Zhang, Wen-Juan; Du, Shu-Shan; Zhang, Ji

2017-01-01

The chemical constituents of the essential oil extracted from Artemisia anethoides and the bioactivities of essential oil against Tribolium castaneum and Lasioderma serricorne were investigated. The main components of the essential oil were 1,8-cineole (36.54%), 2-isopropyl-5-methyl-3-cyclohexen-1-one (10.40%), terpinen-4-ol (8.58%), 2-isopropyltoluene (6.20) and pinocarveol (5.08%). The essential oil of A. anethoides possessed contact and fumigant toxicities against T. castaneum adults (LD 50 = 28.80 μg/adult and LC 50 = 13.05 mg/L air, respectively) and against L. serricorne (LD 50 = 24.03 μg/adult and LD 50 = 8.04 mg/L air, respectively). The crude oil showed repellent activity against T. castaneum and L. serricorne. Especially, the percentage repellency of essential oil was same level with DEET (positive control) against T. castaneum. The results indicated that the essential oil of A. anethoides had the potential to be developed as insecticide and repellent for control of T. castaneum and L. serricorne.

Ontogeny of the sheathing leaf base in maize (Zea mays).

Science.gov (United States)

Johnston, Robyn; Leiboff, Samuel; Scanlon, Michael J

2015-01-01

Leaves develop from the shoot apical meristem (SAM) via recruitment of leaf founder cells. Unlike eudicots, most monocot leaves display parallel venation and sheathing bases wherein the margins overlap the stem. Here we utilized computed tomography (CT) imaging, localization of PIN-FORMED1 (PIN1) auxin transport proteins, and in situ hybridization of leaf developmental transcripts to analyze the ontogeny of monocot leaf morphology in maize (Zea mays). CT imaging of whole-mounted shoot apices illustrates the plastochron-specific stages during initiation of the basal sheath margins from the tubular disc of insertion (DOI). PIN1 localizations identify basipetal auxin transport in the SAM L1 layer at the site of leaf initiation, a process that continues reiteratively during later recruitment of lateral leaf domains. Refinement of these auxin transport domains results in multiple, parallel provascular strands within the initiating primordium. By contrast, auxin is transported from the L2 toward the L1 at the developing margins of the leaf sheath. Transcripts involved in organ boundary formation and dorsiventral patterning accumulate within the DOI, preceding the outgrowth of the overlapping margins of the sheathing leaf base. We suggest a model wherein sheathing bases and parallel veins are both patterned via the extended recruitment of lateral maize leaf domains from the SAM. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

CIRCADIAN CLOCK-ASSOCIATED 1 Inhibits Leaf Senescence in Arabidopsis

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Yi Song

2018-03-01

Full Text Available Leaf senescence is an integral part of plant development, and the timing and progressing rate of senescence could substantially affect the yield and quality of crops. It has been known that a circadian rhythm synchronized with external environmental cues is critical for the optimal coordination of various physiological and metabolic processes. However, the reciprocal interactions between the circadian clock and leaf senescence in plants remain unknown. Here, through measuring the physiological and molecular senescence related markers of several circadian components mutants, we found that CIRCADIAN CLOCK-ASSOCIATED 1 inhibits leaf senescence. Further molecular and genetic studies revealed that CCA1 directly activates GLK2 and suppresses ORE1 expression to counteract leaf senescence. As plants age, the expression and periodic amplitude of CCA1 declines and thus weakens the inhibition of senescence. Our findings reveal an age-dependent circadian clock component of the process of leaf senescence.

Accumulation of three different sizes of particulate matter on plant leaf surfaces: Effect on leaf traits

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Chen Xiaoping

2015-01-01

Full Text Available Plants not only improve air quality by adsorbing particulate matter (PM on leaf surfaces but can also be affected by their accumulation. In this study, a field investigation was performed in Wuhan, China, into the relationship between seven leaf traits and the accumulation of three different sizes of PM (PM11, PM2.5 and PM0.2 on leaves. The retention abilities of plant leaves with respect to the three sizes of PM differed significantly at different sites and species. The average PM retention capabilities of plant leaves and specific leaf area (SLA were significantly greater in a seriously polluted area, whereas the average values of chlorophyll a (Chl a, chlorophyll b (Chl b, total chlorophyll, carotenoid, pH and relative water content (RWC were greater at the control site. SLA significantly positively correlated with the size of PM, but Chl a, Chl b, total chlorophyll, RWC significantly negatively correlated with the size of PM, whereas the pH did not correlate significantly with the the PM fractions. Additionally, SLA was found to be affected by large particles (PM11, p<0.01; PM2.5 had a more obvious effect on plant leaf traits than the other PM (p<0.05. Overall, the findings from this study provide useful information regarding the selection of plants to reduce atmospheric pollution.

Atividade antibacteriana e a preditividade do condimento Artemisia dracunculus Linn. (Asteraceae, variedade inodora - estragão -, frente à Salmonella sp Antimicrobial activity and preditivity of Artemisia acunculus (Asteraceae, var. inodora - tarragon -, as condiment, against Salmonella sp

Directory of Open Access Journals (Sweden)

Heloisa Helena Carvalho

2006-03-01

Full Text Available Avaliou-se a atividade antibacteriana de extrato aquoso do condimento estragão - Artemisia dracunculus linn. (Asteraceae, variedade inodora -, frente à Salmonella enteritidis (ATCC 11076, por meio do sistema de tubos múltiplos e pelo emprego de desinibidores bacterianos, determinando-se a Intensidade de Inibição/Inativação (IINIB/IINAB, observando-se expressiva inibição, bem como ausência de inativação sobre esta salmonela. Na presença do fator matéria orgânica/sujeira representada pelo leite, estes atributos repetiram-se, embora com menor intensidade de inibição. Posteriormente, avaliou-se a preditividade de uma técnica oficial de isolamento desta bactéria, utilizando uma solução experimental de leite e caldo BHI (Brain Heart Infusion, contaminada com 10(4 UFC/mL da salmonela em estudo. Verificou-se a ausência de isolamento desta bactéria em alíquotas de 25 mL, após períodos de 24, 48 e 72 h de incubação a 36ºC, comprometendo a Validade Preditiva dos Resultados Negativos (VPR- do teste. Sugere-se que, nas investigações epidemiológicas de surtos toxiinfectivos alimentares, devem-se ser acrescidas informações sobre condimentação vegetal, entre outras, pertinentes à complexidade crescente do sistema de alimentação e nutrição.It was evaluated antibacterial activity of watery extract of the condiment tarragon - Artemisia dracunculus linn., var. inodora -, against the Salmonella enteritidis (ATCC 11076, through the system of multiple pipes and the job of bacterial inhibitors, it was determined Intensity of inhibition/inativation (IINIB/IINAB, observing expressive inhibition, as well as absence of inativation on this salmonela. In presence of the organic substance, represented by skimmed barren milk, these attributes if had repeated, even so with lesser intensity of inhnibition. Later, it was evaluated preditividade of one official technique of isolation of this bacterium, using an experimental solution of milk

Leaf surface anatomy in some woody plants from northeastern Mexico

International Nuclear Information System (INIS)

Maiti, R.; Rodriguez, H.G.; Balboa, P.C.R.; Kumari, A

2016-01-01

Studies on leaf surface anatomy of woody plants and its significance are rare. The present study was undertaken in the Forest Science Faculty Experimental Research Station, UANL, Mexico, with objectives to determine the variability in leaf surface anatomy in the woody plants of the Tamaulipan thornscrub and its utility in taxonomy and possible adaptation to the prevailing semiarid conditions. The results show the presence of large variability in several leaf anatomical traits viz., waxy leaf surface, type of stomata, its size, and distribution. The species have been classified on the basis of various traits which can be used in species delimitation and adaptation to the semiarid condition such as waxy leaf surface, absence sparse stomata on the leaf surface, sunken stomata. The species identified as better adapters to semi-arid environments on the basis of the presence and absence of stomata on both adaxial and abaxial surface viz., Eysenhardtia texana, Parkinsonia texana, Gymnosperma glutinosum, Celtis laevigata, Condalia hookeri and Karwinskia humboldtiana. (author)

Antibacterial activity, chemical composition, and cytotoxicity of leaf?s essential oil from brazilian pepper tree (schinus terebinthifolius, raddi)

OpenAIRE

Silva, A.B.; Silva, T.; Franco, E.S.; Rabelo, S.A.; Lima, E.R.; Mota, R.A.; da C?mara, C.A.G.; Pontes-Filho, N.T.; Lima-Filho, J.V.

2010-01-01

The antibacterial potential of leaf?s essential oil (EO) from Brazilian pepper tree (Schinus terebinthifolius Raddi) against staphylococcal isolates from dogs with otitis externa was evaluated. The minimum inhibitory concentration of EO ranged from 78.1 to 1,250 ?g/mL. The oil was analyzed by GC and GC/MS and cytotoxicity tests were carried out with laboratory animals.

Effects of canopy structural variables on retrieval of leaf dry matter content and specific leaf area from remotely sensed data

NARCIS (Netherlands)

Ali, A.M.; Darvishzadeh, R.; Skidmore, A.K.; van Duren, I.C.

2016-01-01

Leaf dry matter content (LDMC) and specific leaf area (SLA) are two important traits in measuring biodiversity. To use remote sensing for the estimation of these traits, it is essential to understand the underlying factors that influence their relationships with canopy reflectance. The effect of

[Effects of simulated warming on the growth, leaf phenology, and leaf traits of Salix eriostachya in sub-alpine timberline ecotone of western Sichuan, China].

Science.gov (United States)

Xu, Zhen-feng; Hu, Ting-xing; Zhang, Li; Zhang, Yuan-bin; Xian, Jun-ren; Wang, Kai-yun

2009-01-01

By using open-top chamber (OTC), the effects of simulated warming on the growth, leaf phenology, and leaf traits of Salix eriostachya in sub-alpine timberline ecotone of Western Sichuan were studied. The results showed that comparing with the control, the mean air temperature at 1.2 m above the ground throughout S. eriostachya growth season in OTC increased by 2.9 degrees C, while the soil temperature at the depth of 5 cm only increased by 0.4 degrees C. The temperature increase in OTC made S. eriostachya budding advanced and defoliation postponed obviously, and the leaf life-span longer. The leaf and branch growth rates as well as the specific leaf area in OTC increased obviously, whereas the leaf nitrogen concentration decreased significantly. In OTC, the stomata conductance, net photosynthetic rate, photorespiration, and dark respiration rate of S. eriostachya all exhibited an increasing trend. It was suggested that S. eriostachya had stronger capability to adapt to warming, and, under the background of future global climate change, the elevation of S. eriostachya distribution in the timberline ecotone would be likely to ascend.

Penumbra measurements of BeamModulatorTM multi leaf collimator

International Nuclear Information System (INIS)

Lu Xiaoguang; Wang Yunlai; Huo Xiaoqing; Sha Xiangyan; Miao Xiongfei

2010-01-01

Objective: To evaluate the penumbra of a new multileaf collimator equipped with Elekta Synergy accelerator. Methods: The penumbra were derived from beam profiles measured in air and water using PinPoint ion chamber with PTW MP3 water phantom. Variations of penumbra with X-ray beam energy, depth in water, and leaf position were investigated. Results: The penumbra in air for 6 MV X-ray was 2 mm less than that at depth of maximal dose in water. The penumbra of leaf side was 1 mm less than that of the leaf end. The penumbra had close relationship with beam energy, depth in water and leaf position. penumbra increased with beam quality and water depth. The leaf position had great influence on the penumbra. Conclusions: The penumbra of the multileaf collimator is related to its original design and radiation delivery technique. Special considerations should be taken into during treatment planning. Regular measurement should be performed to guarantee the delivery quality. (authors)

Inverse gradients in leaf wax δD and δ13C values along grass blades of Miscanthus sinensis: implications for leaf wax reproduction and plant physiology.

Science.gov (United States)

Gao, Li; Huang, Yongsong

2013-06-01

Compound specific hydrogen and carbon isotopic ratios of higher plant leaf waxes have been extensively used in paleoclimate and paleoenvironmental reconstructions. However, studies so far have focused on the comparison of leaf wax isotopic differences in bulk leaf samples between different plant species. We sampled three different varieties of tall grasses (Miscanthus sinensis) in six segments from base to tip and determined hydrogen and carbon isotopic ratios of leaf waxes, as well as hydrogen and oxygen isotopic ratios of leaf water samples. We found an increasing, base-to-tip hydrogen isotopic gradient along the grass blades that can probably be attributed to active leaf wax regeneration over the growth season. Carbon isotopic ratios, on the other hand, show opposite trends to hydrogen isotopic ratios along the grass blades, which may reflect different photosynthetic efficiencies at different blade locales.

LEAF MICROMORPHOMETRY OF Schinus molle L. (ANARCADIACEAE IN DIFFERENT CANOPY HEIGHTS.

Directory of Open Access Journals (Sweden)

Marinês Ferreira Pires

2015-03-01

Full Text Available Leaf characterization of trees is essential for its identification and use, as well as to understand its relationships with environment. The objective of this work is to study the leaflet anatomy and leaf biometrical characteristics at different canopy heights of Schinus molle plants as a function of its environmental and physiological modifications. Leaves were collected at three different canopy heights: base, middle and upper canopy in a plantation of S. molle. Leaves were used for anatomical and biometrical analysis. For the anatomical analysis, leaves were fixed in FAA and stored in ethanol 70% and further submitted to transversal and paradermical sections. Slides were photomicrographed and image analysis was performed in UTHSCSA-Imagetool. For biometrical analysis leaf area, length, width, dry mass and specific leaf area were evaluated. The leaflets exhibited single layer epidermis, anomocytic and ciclocytic stomata, isobilateral mesophyll, subepidermal parenchyma layer in both adaxial and abaxial faces of epidermis, secretory vessels and lamellar collenchyma in midrib and leaf border. Leaf anatomy modifications occurred in cuticle and mesophyll thickness, vascular system, phloem thickness, and stomatal density in accordance with leaf canopy position. Leaves were smaller and with reduced leaf area at higher canopy positions. S. molle leaf anatomy is different from other species within Schinus genre with modifications under different environmental and physiological modifications promoted by its canopy height.

The effect of glyphosate on import into a sink leaf of sugar beet

International Nuclear Information System (INIS)

Shieh, Wenjang; Geiger, D.R.

1990-01-01

The basis for glyphosate inducted limitation of carbon import into developing leaves was studied in sugar beet. To separate the effects of the herbicide on export from those on import, glyphosate was supplied to a developing leaf from two exporting source leaves which fed the sink leaf. Carbon import into the sink leaf was determined by supplying 14 CO 2 to a third source leaf which also supplies carbon to the monitored sink leaf. Import into the sink leaf decreased within 2 to 3 h after glyphosate application, even though photosynthesis and export in the source leaf supplying 14 C were unaffected. Reduced import into the sink leaf was accompanied by increased import by the tap root. Elongation of the sink leaf was only slightly decreased following arrival of glyphosate. Photosynthesis by the sink leaf was not inhibited. The results to data support the view that import is slowed by the inhibition of synthesis of structural or storage compounds in the developing leaves

CO2 and temperature effects on leaf area production in two annual plant species

International Nuclear Information System (INIS)

Ackerly, D.D.; Coleman, J.S.; Morse, S.R.; Bazzaz, F.A.

1992-01-01

The authors studied leaf area production in two annual plant species, Abutilon theophrasti and Amaranthus retroflexus, under three day/night temperature regimes and two concentrations of carbon dioxide. The production of whole-plant leaf area during the first 30 d of growth was analyzed in terms of the leaf initiation rate, leaf expansion, individual leaf area, and, in Amaranthus, production of branch leaves. Temperature and CO 2 influenced leaf area production through effects on the rate of development, determined by the production of nodes on the main stem, and through shifts in the relationship between whole-plant leaf area and the number of main stem nodes. In Abutilon, leaf initiation rate was highest at 38 degree, but area of individual leaves was greatest at 28 degree. Total leaf area was greatly reduced at 18 degree due to slow leaf initiation rates. Elevated CO 2 concentration increased leaf initiation rate at 28 degree, resulting in an increase in whole-part leaf area. In Amaranthus, leaf initiation rate increased with temperature, and was increased by elevated CO 2 at 28 degree. Individual leaf area was greatest at 28 degree, and was increased by elevated CO 2 at 28 degree but decreased at 38 degree. Branch leaf area displayed a similar response to CO 2 , butt was greater at 38 degree. Overall, wholeplant leaf area was slightly increased at 38 degree relative to 28 degree, and elevated CO 2 levels resulted in increased leaf area at 28 degree but decreased leaf area at 38 degree

Analysis of leaf surfaces using scanning ion conductance microscopy.

Science.gov (United States)

Walker, Shaun C; Allen, Stephanie; Bell, Gordon; Roberts, Clive J

2015-05-01

Leaf surfaces are highly complex functional systems with well defined chemistry and structure dictating the barrier and transport properties of the leaf cuticle. It is a significant imaging challenge to analyse the very thin and often complex wax-like leaf cuticle morphology in their natural state. Scanning electron microscopy (SEM) and to a lesser extent Atomic force microscopy are techniques that have been used to study the leaf surface but their remains information that is difficult to obtain via these approaches. SEM is able to produce highly detailed and high-resolution images needed to study leaf structures at the submicron level. It typically operates in a vacuum or low pressure environment and as a consequence is generally unable to deal with the in situ analysis of dynamic surface events at submicron scales. Atomic force microscopy also possess the high-resolution imaging required and can follow dynamic events in ambient and liquid environments, but can over exaggerate small features and cannot image most leaf surfaces due to their inherent roughness at the micron scale. Scanning ion conductance microscopy (SICM), which operates in a liquid environment, provides a potential complementary analytical approach able to address these issues and which is yet to be explored for studying leaf surfaces. Here we illustrate the potential of SICM on various leaf surfaces and compare the data to SEM and atomic force microscopy images on the same samples. In achieving successful imaging we also show that SICM can be used to study the wetting of hydrophobic surfaces in situ. This has potentially wider implications than the study of leaves alone as surface wetting phenomena are important in a range of fundamental and applied studies. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

RNAi down-regulation of cinnamate-4-hydroxylase increases artemisinin biosynthesis in Artemisia annua.

Science.gov (United States)

Kumar, Ritesh; Vashisth, Divya; Misra, Amita; Akhtar, Md Qussen; Jalil, Syed Uzma; Shanker, Karuna; Gupta, Madan Mohan; Rout, Prashant Kumar; Gupta, Anil Kumar; Shasany, Ajit Kumar

2016-05-25

Cinnamate-4-hydroxylase (C4H) converts trans-cinnamic acid (CA) to p-coumaric acid (COA) in the phenylpropanoid/lignin biosynthesis pathway. Earlier we reported increased expression of AaCYP71AV1 (an important gene of artemisinin biosynthesis pathway) caused by CA treatment in Artemisia annua. Hence, AaC4H gene was identified, cloned, characterized and silenced in A. annua with the assumption that the elevated internal CA due to knock down may increase the artemisinin yield. Accumulation of trans-cinnamic acid in the plant due to AaC4H knockdown was accompanied with the reduction of p-coumaric acid, total phenolics, anthocyanin, cinnamate-4-hydroxylase (C4H) and phenylalanine ammonia lyase (PAL) activities but increase in salicylic acid (SA) and artemisinin. Interestingly, feeding trans-cinnamic acid to the RNAi line increased the level of artemisinin along with benzoic (BA) and SA with no effect on the downstream metabolites p-coumaric acid, coniferylaldehyde and sinapaldehyde, whereas p-coumaric acid feeding increased the content of downstream coniferylaldehyde and sinapaldehyde with no effect on BA, SA, trans-cinnamic acid or artemisinin. SA is reported earlier to be inducing the artemisinin yield. This report demonstrates the link between the phenylpropanoid/lignin pathway with artemisinin pathway through SA, triggered by accumulation of trans-cinnamic acid because of the blockage at C4H.

7 CFR 29.1162 - Leaf (B Group).

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf (B Group). 29.1162 Section 29.1162 Agriculture... INSPECTION Standards Grades § 29.1162 Leaf (B Group). This group consists of leaves normally grown at or above the midportion of the stalk. Leaves of the B group have a pointed tip, tend to fold, usually are...

Temperature-sensitive leaf color mutation in rice

International Nuclear Information System (INIS)

Shu Qingyao; Liu Guifu; Xia Yingwu

1996-01-01

Studies on the leaf color appearance of 4 chlorophyll-deficient mutation lines both in field and in phytotron were carried out. The mutation lines were induced by 60 Co gamma rays, and showed that white or yellow leaves at seedling stage were quite different from their-parent 2177 S, a thermal sensitive genie male sterile line and any other rice materials. The temperature had great influence on the expression of leaf color at seedling stage in the mutation lines. the leaf color was white at 30∼35 degree C for the lines W 4 and W 11 . The chlorophyll content of 1.5-leaf-age seedlings was 0.0219 and 0.0536 mg/g FW respectively for W 4 and W 11 at 35 degree C. When the temperature dropped to 20∼25 degree C, the seedlings showed yellow or yellowish and the chlorophyll content reached to 0.2410 and 0.3431 mg/g FW at 25 degree C, respectively. However, the responses to temperature for W 17 and W 25 were just the opposite. They were white at 20∼25 degree C, but appeared greenish at 30∼35 degree C. The chlorophyll content increased from 0.0813 and 0.0172 mg/g FW at 25 degree C to 1.0570 and 1.1367 mg/g FW at 35 degree C for the lines W 1 -7 and W 25 , respectively. The parent line 2177 S showed normal green and the chlorophyll content was between 2.108 and 2.118 mg/g FW. The W 11 is exception, which showed yellow to light green in lifetime, and all the mutation lines could convert to normal green after the extension of the fourth leaf. The chlorophyll content of 3.5-leaf-age W 4 and W 17 seedlings grown under 25 degree C reached to 2.2190 and 1.993 mg/g FW, which was about 86. 6% and 81.1% of that of 2177 S at the same stage. When grown at the temperature bellow 20 degree C, W 25 maintained white and could not changed into green after the 4th leaf extension, and showed a conditional lethal status

Diallel analysis of leaf disease resistance in inbred Brazilian popcorn cultivars.

Science.gov (United States)

Vieira, R A; Scapim, C A; Moterle, L M; Tessmann, D J; Conrado, T V; Amaral Júnior, A T

2009-12-01

We estimated general and specific combining abilities and examined resistance to northern leaf blight (Exserohilum turcicum) and to gray leaf spot (Cercospora zeae-maydis) in a set of nine inbred popcorn lines. These inbreds were crossed in a complete diallel scheme without reciprocals, which produced 36 F(1) hybrids. Two experiments with a square lattice design and three replications were conducted during the 2008/2009 crop season, in Maringá, PR, Brazil. The severity of northern leaf blight and gray leaf spot was assessed under natural infestation conditions. Data were examined by individual and joint analysis of variance. Individual and joint Griffing's diallel analyses were carried out for adjusted means. General combining ability and specific combining ability were significant (P < 0.10) by the F-test for northern leaf blight and gray leaf spot infestation levels. This denotes that additive and non-additive gene effects both contributed to resistance to these diseases, but that the additive gene effects were more important. Among the inbred lines, P(8) and P(9) gave the highest resistance to northern leaf blight, and P(3) and P(4.3) gave the highest resistance to gray leaf spot. The hybrids P(7.4) x P(8) and P(4.3) x P(9) could be exploited by reciprocal recurrent selection to provide genotypes with both northern leaf blight and gray leaf spot resistance. Significant interaction between general combining ability and crop season (P < 0.10) denotes the importance of environment, even though the disease levels in the hybrids were quite consistent.

Novel insect leaf-mining after the end-Cretaceous extinction and the demise of cretaceous leaf miners, Great Plains, USA.

Directory of Open Access Journals (Sweden)

Michael P Donovan

Full Text Available Plant and associated insect-damage diversity in the western U.S.A. decreased significantly at the Cretaceous-Paleogene (K-Pg boundary and remained low until the late Paleocene. However, the Mexican Hat locality (ca. 65 Ma in southeastern Montana, with a typical, low-diversity flora, uniquely exhibits high damage diversity on nearly all its host plants, when compared to all known local and regional early Paleocene sites. The same plant species show minimal damage elsewhere during the early Paleocene. We asked whether the high insect damage diversity at Mexican Hat was more likely related to the survival of Cretaceous insects from refugia or to an influx of novel Paleocene taxa. We compared damage on 1073 leaf fossils from Mexican Hat to over 9000 terminal Cretaceous leaf fossils from the Hell Creek Formation of nearby southwestern North Dakota and to over 9000 Paleocene leaf fossils from the Fort Union Formation in North Dakota, Montana, and Wyoming. We described the entire insect-feeding ichnofauna at Mexican Hat and focused our analysis on leaf mines because they are typically host-specialized and preserve a number of diagnostic morphological characters. Nine mine damage types attributable to three of the four orders of leaf-mining insects are found at Mexican Hat, six of them so far unique to the site. We found no evidence linking any of the diverse Hell Creek mines with those found at Mexican Hat, nor for the survival of any Cretaceous leaf miners over the K-Pg boundary regionally, even on well-sampled, surviving plant families. Overall, our results strongly relate the high damage diversity on the depauperate Mexican Hat flora to an influx of novel insect herbivores during the early Paleocene, possibly caused by a transient warming event and range expansion, and indicate drastic extinction rather than survivorship of Cretaceous insect taxa from refugia.

Novel insect leaf-mining after the end-Cretaceous extinction and the demise of cretaceous leaf miners, Great Plains, USA.

Science.gov (United States)

Donovan, Michael P; Wilf, Peter; Labandeira, Conrad C; Johnson, Kirk R; Peppe, Daniel J

2014-01-01

Plant and associated insect-damage diversity in the western U.S.A. decreased significantly at the Cretaceous-Paleogene (K-Pg) boundary and remained low until the late Paleocene. However, the Mexican Hat locality (ca. 65 Ma) in southeastern Montana, with a typical, low-diversity flora, uniquely exhibits high damage diversity on nearly all its host plants, when compared to all known local and regional early Paleocene sites. The same plant species show minimal damage elsewhere during the early Paleocene. We asked whether the high insect damage diversity at Mexican Hat was more likely related to the survival of Cretaceous insects from refugia or to an influx of novel Paleocene taxa. We compared damage on 1073 leaf fossils from Mexican Hat to over 9000 terminal Cretaceous leaf fossils from the Hell Creek Formation of nearby southwestern North Dakota and to over 9000 Paleocene leaf fossils from the Fort Union Formation in North Dakota, Montana, and Wyoming. We described the entire insect-feeding ichnofauna at Mexican Hat and focused our analysis on leaf mines because they are typically host-specialized and preserve a number of diagnostic morphological characters. Nine mine damage types attributable to three of the four orders of leaf-mining insects are found at Mexican Hat, six of them so far unique to the site. We found no evidence linking any of the diverse Hell Creek mines with those found at Mexican Hat, nor for the survival of any Cretaceous leaf miners over the K-Pg boundary regionally, even on well-sampled, surviving plant families. Overall, our results strongly relate the high damage diversity on the depauperate Mexican Hat flora to an influx of novel insect herbivores during the early Paleocene, possibly caused by a transient warming event and range expansion, and indicate drastic extinction rather than survivorship of Cretaceous insect taxa from refugia.

Herba Artemisiae Capillaris Extract Prevents the Development of Streptozotocin-Induced Diabetic Nephropathy of Rat

Directory of Open Access Journals (Sweden)

Jianan Geng

2018-01-01

Full Text Available Diabetic nephropathy (DN is a major cause of end-stage renal disease throughout the world; until now there is no specific drug available. In this work, we use herba artemisiae capillaris extract (HACE to alleviate renal fibrosis characterized by the excessive accumulation of extracellular matrix (ECM in rats, aiming to investigate the protective effect of the HACE on DN. We found that the intragastric treatment of high-dose HACE could reverse the effect of streptozotocin not only to decrease the level of blood glucose and blood lipid in different degree but also further to improve renal functions. It is worth mentioning that the effect of HACE treatment was comparable to the positive drug benazepril. Moreover, we found that HACE treatment could on one hand inhibit oxidative stress in DN rats through regulating enzymatic activity for scavenging reactive oxygen species and on the other hand increase the ECM degradation through regulating the activity of metalloproteinase-2 (MMP-2 and the expression of tissue transglutaminase (tTG, which explained why HACE treatment inhibited ECM accumulation. On the basis of above experimental results, we conclude that HACE prevents DN development in a streptozotocin-induced DN rat model, and HACE is a promising candidate to cure DN in clinic.

Characterization of a sagebrush (Artemisia tridentata ssp. wyomingensis) die-off on the Handford Site

International Nuclear Information System (INIS)

Cardenas, A.; Lewinsohn, J.; Auger, C.; Downs, J.L.; Cadwell, L.L.; Burrows, R.

1997-09-01

The Hanford Site contains one of the few remaining contiguous areas of shrub-steppe habitat left in Washington State. This habitat is home to many native plant and wildlife species, some of which are threatened with extinction or are unique to the Site. The importance of the Hanford Site increases as other lands surrounding the Site are developed, and these native species and habitats are lost. Stands of Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) on the Site are a particularly important component of shrub-steppe habitat, because a number of wildlife require big sagebrush for food and cover. Since 1993, researchers and field biologists have made anecdotal observations of dying and declining sagebrush in stands of shrubs near the 100 Areas. This study was initiated to delineate and document the general boundary where sagebrush stands appear to be declining. We mapped the areal extent of the die-off using a global positioning system and found that the central portion of the die-off encompasses 280 hectares. Shrub stand defoliation was estimated to be near or greater than 80% in this area. The remainder of the die-off area exhibits varying mixtures of completely defoliated, partially defoliated, and healthy-looking stands. Declining sagebrush stands comprise a total of 1776 hectares

Characterization of a sagebrush (Artemisia tridentata ssp. wyomingensis) die-off on the Handford Site

Energy Technology Data Exchange (ETDEWEB)

Cardenas, A.; Lewinsohn, J.; Auger, C.; Downs, J.L.; Cadwell, L.L.; Burrows, R.

1997-09-01

The Hanford Site contains one of the few remaining contiguous areas of shrub-steppe habitat left in Washington State. This habitat is home to many native plant and wildlife species, some of which are threatened with extinction or are unique to the Site. The importance of the Hanford Site increases as other lands surrounding the Site are developed, and these native species and habitats are lost. Stands of Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) on the Site are a particularly important component of shrub-steppe habitat, because a number of wildlife require big sagebrush for food and cover. Since 1993, researchers and field biologists have made anecdotal observations of dying and declining sagebrush in stands of shrubs near the 100 Areas. This study was initiated to delineate and document the general boundary where sagebrush stands appear to be declining. We mapped the areal extent of the die-off using a global positioning system and found that the central portion of the die-off encompasses 280 hectares. Shrub stand defoliation was estimated to be near or greater than 80% in this area. The remainder of the die-off area exhibits varying mixtures of completely defoliated, partially defoliated, and healthy-looking stands. Declining sagebrush stands comprise a total of 1776 hectares.

Leaf Surface Effects on Retrieving Chlorophyll Content from Hyperspectral Remote Sensing

Science.gov (United States)

Qiu, Feng; Chen, JingMing; Ju, Weimin; Wang, Jun; Zhang, Qian

2017-04-01

Light reflected directly from the leaf surface without entering the surface layer is not influenced by leaf internal biochemical content. Leaf surface reflectance varies from leaf to leaf due to differences in the surface roughness features and is relatively more important in strong absorption spectral regions. Therefore it introduces dispersion of data points in the relationship between biochemical concentration and reflectance (especially in the visible region). Separation of surface from total leaf reflection is important to improve the link between leaf pigments content and remote sensing data. This study aims to estimate leaf surface reflectance from hyperspectral remote sensing data and retrieve chlorophyll content by inverting a modified PROSPECT model. Considering leaf surface reflectance is almost the same in the visible and near infrared spectral regions, a surface layer with a reflectance independent of wavelength but varying from leaf to leaf was added to the PROSPECT model. The specific absorption coefficients of pigments were recalibrated. Then the modified model was inverted on independent datasets to check the performance of the model in predicting the chlorophyll content. Results show that differences in estimated surface layer reflectance of various species are noticeable. Surface reflectance of leaves with epicuticular waxes and trichomes is usually higher than other samples. Reconstruction of leaf reflectance and transmittance in the 400-1000 nm wavelength region using the modified PROSPECT model is excellent with low root mean square error (RMSE) and bias. Improvements for samples with high surface reflectance (e.g. maize) are significant, especially for high pigment leaves. Moreover, chlorophyll retrieved from inversion of the modified model is consequently improved (RMSE from 5.9-13.3 ug/cm2 with mean value 8.1 ug/cm2, while mean correlation coefficient is 0.90) compared to results of PROSPECT-5 (RMSE from 9.6-20.2 ug/cm2 with mean value 13

Fire ants protect mealybugs against their natural enemies by utilizing the leaf shelters constructed by the leaf roller Sylepta derogata.

Directory of Open Access Journals (Sweden)

Aiming Zhou

Full Text Available The importance of mutualism is receiving more attention in community ecology. In this study, the fire ant Solenopsis invicta was found to take advantage of the shelters constructed by the leaf roller Sylepta derogata to protect mealybugs (Phenacoccus solenopsis against their natural enemies. This protective effect of fire ant tending on the survival of mealybugs in shelters was observed when enemies and leaf rollers were simultaneously present. Specifically, fire ants moved the mealybugs inside the shelters produced by S. derogata on enemy-infested plants. Compared with that in plants without ants, the survival of mealybugs in shelters in the presence of natural enemies in plants with ants markedly improved. Both the protection of ants and the shelters provided by leaf rollers did not affect the survival of mealybugs in the absence of enemies in plants. Ants and leaf rollers significantly improved the survival of mealybugs in predator-infested plants, whereas no such improvement was observed in parasitoid-infested ones.

Theoretical analysis of radiation field penumbra from a multi leaf collimator

International Nuclear Information System (INIS)

Li Shidong; Boyer, Arthur; Findley, David; Mok, Ed

1996-01-01

Purpose/Objective: Analysis and measurement of the difference between the light field and the radiation field of the multi leaf collimator (MLC) leaves that are constructed with curved ends. Material and Methods: A Varian MLC with curved leaf ends was installed on a Clinac 2300 C/D. The leaves were 6.13 cm deep (dimension in beam direction) and were located 53.9 cm from the x-ray target. The leaf ends had an 8 cm radius of curvature. A relation was derived using three dimensional geometry predicting the location of the light field edge relative to the geometric projection of the tip of the curved leaf end. This is a nonlinear relationship because the shadow of the leaf is generated by different points along the leaf end surface as the leaf moves across the field. The theoretical edge of the radiation fluence for a point source was taken to be located along the projection of a chord whose length was 1 Half-Value Thickness (HVT). The chords having projection points across the light field edge were computed using an analytical solution. The radiation transmission through the leaf end was then estimated. The HVT used for tungsten alloy, the leaf material, was 0.87 cm and 0.94 cm for the 6 MV and 15 MV photon beams, respectively. The location of the projection of the 1 HVT chord at a distance of 100 cm from x-ray target was also a nonlinear function of the projection of the leaf tip. Results: The displacement of the light field edge relative to the projection of the leaf tip varies from 0 mm when the leaf tip projects to the central axis, to approximately 3.2 mm for a 20 cm half-field width. The light field edge was always displaced into the unblocked area. The displacement of the projection of the 1 HVT chord relative to the projection of the leaf tip varies from 0.3 mm on the central axis to 3.0 mm for a 20 cm half-field width. The projection of 1 HVT chord was deviated from the light field edge by only 0.3 mm which would be slightly increased to 0.4 mm on decreasing

Short Communication: The developmentt of a leaf tensilmeter for in ...

African Journals Online (AJOL)

The development of a portable leaf tensilmeter for the in situ measurement of leaf tensile strength is described. Tensile strength is determined by the distortion of strain gauges on modified stripping pliers which are used to break leaf blades. The output is displayed via an analogue chip through a liquid crystal display.

Plant traits and environment: floating leaf blade production and turnover of waterlilies.

Science.gov (United States)

Klok, Peter F; van der Velde, Gerard

2017-01-01

Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L.) Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba , Nuphar lutea , Nymphaea candida . The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/B max ) of the three species ranged from 1.35-2.25. The ratio Vegetation period (Period with floating leaves)/Mean leaf life span ranged from 2.94-4.63, the ratio Growth period (Period with appearance of new floating leaves)/Vegetation period from 0.53-0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba , may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.

The Cytotoxic, Antibacterial and Free Radical Scavenging Activities of Crude Extracts of Matricaria chamomilla, Salvadora persica and Artemisia annua

KAUST Repository

Seddek, Ahmed

2011-12-01

The discovery of drugs from natural sources has been a rapidly growing science in this era. Plants used for medicinal purposes have been usually studied as rich sources of bioactive chemical compounds that can be used as medications. Several plant-derived drugs have been approved so far. Cancer and infectious diseases have been common targets for the science of drug discovery, due to the high mortality rates caused by these diseases all over the world. Several plant-derived compounds are being marketed now as anti-cancer agents. However, finding novel antimicrobial and anti-cancer compounds has become an important goal to overcome the problems of existing anti-cancer and antimicrobial agents, such as resistance and non-selectivity. In this thesis project, an attempt to find out useful biological activities of the crude extracts of some plants used traditionally for medicinal purposes in Saudi Arabia has been made. Matricaria chamomilla, Salvadora persica and Artemisia annua have been selected for study, based on the literature review performed. These plants were screened for three biological activities; anti-cancer, anti-bacterial and free radical scavenging activities. The experimental part of the study consisted of some common in-vitro techniques, such as cytotoxicity and cell viability assays, disk diffusion assay and 1,1-diphenyl-2-picryl-hydrazyl assay. In addition, the crude extract of Matricaria chamomilla has undergone chemical fractionation and four solvent fractions were obtained using column chromatography. The crude extract of Matricaria chamomilla showed a promising anti-bacterial activity against Escherichia coli and a very promising free radical scavenging activity that was comparable to ascorbic acid, an important anti-oxidant. The four solvent fractions obtained from that extract showed that these activities were produced by more than one compound belonging to different solvent fractions. In addition, the crude extract of Artemisia annua showed

Incomplete resistance to coffee leaf rust (Hemileia vastatrix)

NARCIS (Netherlands)

Eskes, A.B.

1983-01-01

Incomplete resistance to coffee leaf rust ( Hemileia vastatrix ) may be of value in obtaining durable resistance, which is of great importance for the perennial coffee crop. Methods were developed to assess incomplete resistance to coffee leaf rust by using illustrated scales

cassava brown streak disease effects on leaf metabolites

African Journals Online (AJOL)

USER

Plate 1. Progression of CBSD in cassava leaves with scores 1= leaf from clean plant, no CBSD, 2 = Mild CBSD leaf veinal ... absorb the excess water, after which they were rolled ..... to low carbon dioxide exchange, as observed in sugar cane ...

Leaf gas exchange of mature bottomland oak trees

Science.gov (United States)

Rico M. Gazal; Mark E. Kubiske; Kristina F. Connor

2009-01-01

We determined how changes in environmental moisture affected leaf gas exchange in Nuttall (Quercus texana Buckley), overcup (Q. lyrata Walt.), and dominant and codominant swamp chestnut (Q. michauxii Nutt.) oak trees in Mississippi and Louisiana. We used canopy access towers to measure leaf level gas...

Leaf area estimation of cassava from linear dimensions

Directory of Open Access Journals (Sweden)

SAMARA ZANETTI

2017-08-01

Full Text Available ABSTRACT The objective of this study was to determine predictor models of leaf area of cassava from linear leaf measurements. The experiment was carried out in greenhouse in the municipality of Botucatu, São Paulo state, Brazil. The stem cuttings with 5-7 nodes of the cultivar IAC 576-70 were planted in boxes filled with about 320 liters of soil, keeping soil moisture at field capacity, monitored by puncturing tensiometers. At 80 days after planting, 140 leaves were randomly collected from the top, middle third and base of cassava plants. We evaluated the length and width of the central lobe of leaves, number of lobes and leaf area. The measurements of leaf areas were correlated with the length and width of the central lobe and the number of lobes of the leaves, and adjusted to polynomial and multiple regression models. The linear function that used the length of the central lobe LA = -69.91114 + 15.06462L and linear multiple functions LA = -69.9188 + 15.5102L + 0.0197726K - 0.0768998J or LA = -69.9346 + 15.0106L + 0.188931K - 0.0264323H are suitable models to estimate leaf area of cassava cultivar IAC 576-70.

Sorption of lead from aqueous solutions by spent tea leaf | Yoshita ...

African Journals Online (AJOL)

Pb) from solution. The Pb removal by the spent tea leaf adsorbent depended on pretreatment of spent tea leaf, adsorption contact time and adsorbent dosage. The optimum pretreatment conditions were confirmed to be that tea leaf was ground ...

Effects of artemisinin and Artemisia annua extracts on xenic bacteria isolated from clonal cultures of Histomonas meleagridis

DEFF Research Database (Denmark)

Thøfner, I.C.N.; Hess, C.; Liebhart, D.

Infection with the protozoa Histomonas meleagridis in poultry has re-emerged since the ban of effective drugs. Consequently efforts are set to find alternatives to chemotherapeutics to combat histomonosis. At present histomonads need accompanying bacteria when cultured in vitro, probably serving...... nutrient supply due to their appearance in parasitic food vacuoles. However, the relationship of the parasite and the bacteria is not fully clear. Six previously established clonal cultures of H. meleagridis were used to evaluate the effect of five Artemisia annua derived materials (i.e. dry leaves...... with the antibacterial tests, it is reasonable to assume that the observed inhibitory effect of the tested materials is attributed to a direct effect on the protozoa. However, the potential of these materials on histomonosis has been tested in vivo in chickens and in turkeys without success....

Fumigant and repellent activities of essential oil extracted from Artemisia dubia and its main compounds against two stored product pests.

Science.gov (United States)

Liang, Jun-Yu; Guo, Shan-Shan; Zhang, Wen-Juan; Geng, Zhu-Feng; Deng, Zhi-Wei; Du, Shu-Shan; Zhang, Ji

2018-05-01

The major chemical constituents of the essential oil extracted from Artemisia dubia wall. ex Bess. (Family: Asteraceae) were found as terpinolene (19.02%), limonene (17.40%), 2,5-etheno[4.2.2]propella-3,7,9-triene (11.29%), isoelemicin (11.05%) and p-cymene-8-ol (5.93%). Terpinolene and limonene were separated as main components from the essential oil. The essential oil showed fumigant toxicity against Tribolium castaneum and Liposcelis bostrychophila with LC 50 values of 49.54 and 0.74 mg/L, respectively. The essential oil and isolated compounds of A. dubia showed repellency activities against both insects. Terpinolene and limonene showed the fumigant toxicity against T. castaneum. Terpinolene showed obvious fumigant toxicity against L. bostrychophila. The results indicated that the essential oil of A. dubia had potential to be developed into natural insecticides for controlling stored product pests.

Leaf appearance rate and final main stem leaf number as affected by temperature and photoperiod in cereals grown in Mediterranean environment

Directory of Open Access Journals (Sweden)

Ezio Riggi

2017-09-01

Full Text Available In the present study, a two-year field trial was carried out with the aim to evaluate daylength and air temperature effects on leaf appearance and related rates in two durum wheat (Triticum durum Desf., two bread wheat (Triticum aestivum L. and two barley (Hordeum vulgare L. cultivars, using six different sowing dates (SD. Significant effects of SD on final main stem leaf number (FLN, thermal leaf appearance rate (TLAR, daily leaf appearance rate (DLAR and phyllochron (PhL were found. Cultivars resulted inversely correlated to mean air temperature in the interval emergence - fifth leaf full expansion (E-V. Linear response of leaf number over days after sowing was shown for all SD and cultivars, with R2 higher than 0.95. FLN linearly decreased from the first to the last SD for durum wheat, while more variable behaviour was observed in bread wheat. TLAR and DLAR showed a linear increment of the rate from the first to the last SD in durum wheat, while did not for bread wheat and barley. PhL in durum wheat decreased from the first to the last SD. Barley and bread wheat showed the highest values on those SDs which did not reach flowering. The increase of TLAR was affected by photoperiod and photothermal units in durum wheat, while by temperatures only in barley and bread wheat. Present results might find practical application in the improvement of phenology simulation models for durum wheat, bread wheat and barley grown in Mediterranean area in absence of water and nutrient stress.

Non-destructive linear model for leaf area estimation in Vernonia ferruginea Less

Directory of Open Access Journals (Sweden)

MC. Souza

Full Text Available Leaf area estimation is an important biometrical trait for evaluating leaf development and plant growth in field and pot experiments. We developed a non-destructive model to estimate the leaf area (LA of Vernonia ferruginea using the length (L and width (W leaf dimensions. Different combinations of linear equations were obtained from L, L2, W, W2, LW and L2W2. The linear regressions using the product of LW dimensions were more efficient to estimate the LA of V. ferruginea than models based on a single dimension (L, W, L2 or W2. Therefore, the linear regression “LA=0.463+0.676WL” provided the most accurate estimate of V. ferruginea leaf area. Validation of the selected model showed that the correlation between real measured leaf area and estimated leaf area was very high.

Leaf life span plasticity in tropical seedlings grown under contrasting light regimes.

Science.gov (United States)

Vincent, Gregoire

2006-02-01

The phenotypic plasticity of leaf life span in response to low resource conditions has a potentially large impact on the plant carbon budget, notably in evergreen species not subject to seasonal leaf shedding, but has rarely been well documented. This study evaluates the plasticity of leaf longevity, in terms of its quantitative importance to the plant carbon balance under limiting light. Seedlings of four tropical tree species with contrasting light requirements (Alstonia scholaris, Hevea brasiliensis, Durio zibethinus and Lansium domesticum) were grown under three light regimes (full sunlight, 45 % sunlight and 12 % sunlight). Their leaf dynamics were monitored over 18 months. All species showed a considerable level of plasticity with regard to leaf life span: over the range of light levels explored, the ratio of the range to the mean value of life span varied from 29 %, for the least plastic species, to 84 %, for the most. The common trend was for leaf life span to increase with decreasing light intensity. The plasticity apparent in leaf life span was similar in magnitude to the plasticity observed in specific leaf area and photosynthetic rate, implying that it has a significant impact on carbon gain efficiency when plants acclimate to different light regimes. In all species, median survival time was negatively correlated with leaf photosynthetic capacity (or its proxy, the nitrogen content per unit area) and leaf emergence rate. Longer leaf life spans under low light are likely to be a consequence of slower ageing as a result of a slower photosynthetic metabolism.

Linkage between canopy water storage and drop size distributions of leaf drips

Science.gov (United States)

Nanko, Kazuki; Watanabe, Ai; Hotta, Norifumi; Suzuki, Masakazu

2013-04-01

Differences in drop size distribution (DSD) of leaf drips among tree species have been estimated and physically interpreted to clarify the leaf drip generation process. Leaf drip generation experiments for nine species were conducted in an indoor location without foliage vibration using an automatic mist spray. Broad-leaved species produced a similar DSD among species whose leaves had a matte surface and a second similar DSD among species whose leaves had a coated surface. The matte broad leaves produced a larger and wider range of DSDs than the coated broad leaves. Coated coniferous needles had a wider range of DSDs than the coated broad leaves and different DSDs were observed for different species. The species with shorter dense needles generated a larger DSD. The leaf drip diameter was calculated through the estimation of a state of equilibrium of a hanging drop on the leaves based on physical theory. The calculations indicated that the maximum diameter of leaf drips was determined by the contact angle, and the range of DSDs was determined by the variation in contact length and the contact diameter at the hanging points. The results revealed that leaf drip DSD changed due to variations in leaf hydrophobicity, leaf roughness, leaf geometry and leaf inclination among the different tree species. This study allows the modelization of throughfall DSD. Furthermore, it indicates the possibility of interpreting canopy water processes from canopy water storage to drainage through the contact angle and leaf drip DSD. The part of this study is published in Nanko et al. (2013, Agric. Forest. Meteorol. 169, 74-84).

Plant traits and environment: floating leaf blade production and turnover of waterlilies

Directory of Open Access Journals (Sweden)

Peter F. Klok

2017-04-01

Full Text Available Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L. Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba, Nuphar lutea, Nymphaea candida. The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/Bmax of the three species ranged from 1.35–2.25. The ratio Vegetation period (Period with floating leaves/Mean leaf life span ranged from 2.94–4.63, the ratio Growth period (Period with appearance of new floating leaves/Vegetation period from 0.53–0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba, may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.

Effects of combination of leaf resources on competition in container mosquito larvae.

Science.gov (United States)

Reiskind, M H; Zarrabi, A A; Lounibos, L P

2012-08-01

Resource diversity is critical to fitness in many insect species, and may determine the coexistence of competitive species and the function of ecosystems. Plant material provides the nutritional base for numerous aquatic systems, yet the consequences of diversity of plant material have not been studied in aquatic container systems important for the production of mosquitoes. To address how diversity in leaf detritus affects container-inhabiting mosquitoes, we examined how leaf species affect competition between two container inhabiting mosquito larvae, Aedes aegypti and Aedes albopictus, that co-occur in many parts of the world. We tested the hypotheses that leaf species changes the outcome of intra- and interspecific competition between these mosquito species, and that combinations of leaf species affect competition in a manner not predictable based upon the response to each leaf species alone (i.e. the response to leaf combinations is non-additive). We find support for our first hypothesis that leaf species can affect competition, evidence that, in general, leaf combination alters competitive interactions, and no support that leaf combination impacts interspecific competition differently than intraspecific competition. We conclude that combinations of leaves increase mosquito production non-additively such that combinations of leaves act synergistically, in general, and result in higher total yield of adult mosquitoes in most cases, although certain leaf combinations for A. albopictus are antagonistic. We also conclude that leaf diversity does not have a different effect on interspecific competition between A. aegypti and A. albopictus, relative to intraspecific competition for each mosquito.

7 CFR 29.2662 - Heavy Leaf (B Group).

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Heavy Leaf (B Group). 29.2662 Section 29.2662 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... REGULATIONS TOBACCO INSPECTION Standards Grades § 29.2662 Heavy Leaf (B Group). This group consists of leaves...

Coconut leaf bioactivity toward generalist maize insect pests

Science.gov (United States)

Tropical plants are often more resistant to insects than temperate plants due to evolution of robust defenses to cope with a more constant insect threat. Coconut (Cocos nucifera L.) has very few chewing leaf feeding insect pests and was tested against two omnivorous leaf feeding caterpillar species,...

Nutritive evaluation of Telfairia occidentalis leaf protein concentrate ...

African Journals Online (AJOL)

Leaf meal (LM), leaf proteins concentrate (LPC) and LPC residues from Telfairia occidentalis were produced, chemically characterized and the protein quality of the LPC evaluated using rats. Five infant weaning foods were formulated using varying combinations of T. occidentalis LPC and soybean meal. These foods were ...

Bioactive constituents of Chinese natural medicines. I. New sesquiterpene ketones with vasorelaxant effect from Chinese moxa, the processed leaves of Artemisia argyi Levl. et Vant.: moxartenone and moxartenolide.

Science.gov (United States)

Yoshikawa, M; Shimada, H; Matsuda, H; Yamahara, J; Murakami, N

1996-09-01

Two new sesquiterpene ketones, moxartenone and moxartenolide, and three octadecadienoic acids were isolated from Chinese moxa, the processed leaves of Artemisia argyi LEVL. et VANT., together with two sesquiterpenes, five triterpenes, two phenyl propanoids and three polyoxyflavones. The chemical structures of new sesquiterpenes, moxartenone, moxartenolide, and octadecadienoic acids were determined on the basis of chemical and physiochemical evidence. Moxartenolide was found to inhibit the contractions induced by a high concentration of K+, by norepinephrine, and by serotonin in isolated aortic strips of rat, while moxartenone showed little activity.

Peach leaf responses to soil and cement dust pollution.

Science.gov (United States)

Maletsika, Persefoni A; Nanos, George D; Stavroulakis, George G

2015-10-01

Dust pollution can negatively affect plant productivity in hot, dry and with high irradiance areas during summer. Soil or cement dust were applied on peach trees growing in a Mediterranean area with the above climatic characteristics. Soil and cement dust accumulation onto the leaves decreased the photosynthetically active radiation (PAR) available to the leaves without causing any shade effect. Soil and mainly cement dust deposition onto the leaves decreased stomatal conductance, photosynthetic and transpiration rates, and water use efficiency due possibly to stomatal blockage and other leaf cellular effects. In early autumn, rain events removed soil dust and leaf functions partly recovered, while cement dust created a crust partially remaining onto the leaves and causing more permanent stress. Leaf characteristics were differentially affected by the two dusts studied due to their different hydraulic properties. Leaf total chlorophyll decreased and total phenol content increased with dust accumulation late in the summer compared to control leaves due to intense oxidative stress. The two dusts did not cause serious metal imbalances to the leaves, except of lower leaf K content.

Evaluating a tobacco leaf humidification system involving nebulisation

Directory of Open Access Journals (Sweden)

Néstor Enrique Cerquera Peña

2010-05-01

Full Text Available A tobacco leaf humidifying system involving nebulisation was designned, implemented and evaluated; it had a system for monitoring and recording environmental conditions thereby producing an environment having more homogeneous relative humidity, ensuring better water use, better control of relative humidity and better control in managing cured tobacco leaf moisture content, thereby leading to a consequent improvement in final product quality. 55% to 75% relative humidity and 4 to 6 hour working ranges were obtained to en- sure leaf humidification reached 16% humidity on a wet basis. Two new designs are proposed for the conditioning stage regarding this conditioning chamber’s operational management, based on the results and field observations, which would allow better leaf management, thereby avoiding the risk of losses due to manipulation and over-humidification. This work strengthens research in the field of tobacco pos- tharvest technology, complementing other research projects which have been carried out in Colombia.

Sugarbeet leaf spot disease (Cercospora beticola Sacc.)dagger.

Science.gov (United States)

Weiland, John; Koch, Georg

2004-05-01

SUMMARY Leaf spot disease caused by Cercospora beticola Sacc. is the most destructive foliar pathogen of sugarbeet worldwide. In addition to reducing yield and quality of sugarbeet, the control of leaf spot disease by extensive fungicide application incurs added costs to producers and repeatedly has selected for fungicide-tolerant C. beticola strains. The genetics and biochemistry of virulence have been examined less for C. beticola as compared with the related fungi C. nicotianae, C. kikuchii and C. zeae-maydis, fungi to which the physiology of C. beticola is often compared. C. beticola populations generally are not characterized as having race structure, although a case of race-specific resistance in sugarbeet to C. beticola has been reported. Resistance currently implemented in the field is quantitatively inherited and exhibits low to medium heritability. Cercospora beticola Sacc.; Kingdom Fungi, Subdivision Deuteromycetes, Class Hyphomycetes, Order Hyphales, Genus Cercospora. Circular, brown to red delimited spots with ashen-grey centre, 0.5-6 mm diameter; dark brown to black stromata against grey background; pale brown unbranched sparingly septate conidiophores, hyaline acicular conidia, multiseptate, from 2.5 to 4 microm wide and 50-200 microm long. Propagative on Beta vulgaris and most species of Beta. Reported on members of the Chenopodiaceae and on Amaranthus. Disease symptoms: Infected leaves and petioles of B. vulgaris exhibit numerous circular leaf spots that coalesce in severe cases causing complete leaf collapse. Dark specks within a grey spot centre are characteristic for the disease. Older leaves exhibit a greater number of lesions with larger spot diameter. During the latter stage of severe epiphytotics, new leaf growth can be seen emerging from the plant surrounded by prostrate, collapsed leaves. Fungicides in the benzimidazole and triazole class as well as organotin derivatives and strobilurins have successfully been used to control Cercospora

Responses of rubber leaf phenology to climatic variations in Southwest China

Science.gov (United States)

Zhai, De-Li; Yu, Haiying; Chen, Si-Chong; Ranjitkar, Sailesh; Xu, Jianchu

2017-11-01

The phenology of rubber trees (Hevea brasiliensis) could be influenced by meteorological factors and exhibits significant changes under different geoclimates. In the sub-optimal environment in Xishuangbanna, rubber trees undergo lengthy periods of defoliation and refoliation. The timing of refoliation from budburst to leaf aging could be affected by powdery mildew disease (Oidium heveae), which negatively impacts seed and latex production. Rubber trees are most susceptible to powdery mildew disease at the copper and leaf changing stages. Understanding and predicting leaf phenology of rubber trees are helpful to develop effective means of controlling the disease. This research investigated the effect of several meteorological factors on different leaf phenological stages in a sub-optimal environment for rubber cultivation in Jinghong, Yunnan in Southwest China. Partial least square regression was used to quantify the relationship between meteorological factors and recorded rubber phenologies from 2003 to 2011. Minimum temperature in December was found to be the critical factor for the leaf phenology development of rubber trees. Comparing the delayed effects of minimum temperature, the maximum temperature, diurnal temperature range, and sunshine hours were found to advancing leaf phenologies. A comparatively lower minimum temperature in December would facilitate the advancing of leaf phenologies of rubber trees. Higher levels of precipitation in February delayed the light green and the entire process of leaf aging. Delayed leaf phenology was found to be related to severe rubber powdery mildew disease. These results were used to build predictive models that could be applied to early warning systems of rubber powdery mildew disease.

Phenotypic characterization and inheritance of two foliar mutants in pea (Pisum Sativum L.): 'Reduced leaf size' and 'Orange leaf'

International Nuclear Information System (INIS)

Naidenova, N.; Vassilevska-Ivanova, R.; Tcekova, Z.

2003-01-01

Two foliar pea (Pisum sativum L.) mutants characterized by reduced leaf size (2/978) and orange leaf (2/1409 M) were established. Both mutants were described morphologically and their productivity potential , pollen viability and inheritance of the mutant traits were evaluated. The mutant 2/978 was identified after irradiation of dry seeds from cv Borek with 15 Gy fast neutrons and was related to the leaf mutation 'rogue'. Reciprocal crosses between mutant 2/978 and cv Borel were executed, and F 1 and F 2 generations were analyzed. The altered leaf trait was presented in all F 1 plants suggesting a dominant character. F 2 segregation data indicated that the trait was controlled by a single dominant gene. The mutant 2/1409M originated from the mutant 2/978 after irradiation with 50 Gy γ-rays. The main mutant's phenotypic characteristic was the orange-yellow coloration of leaves and plants. After of series of crosses it was established that induced chlorophyll mutation is monogenic, recessive and both mutant traits are independently inherited. Two mutants could be used as appropriate plant material for genetic and biological investigations

The infrared emissivities of soil and Artemisia tridentata and subsequent temperature corrections in a shrub-steppe ecosystem

International Nuclear Information System (INIS)

Hipps, L.E.

1989-01-01

The determination of plant and soil temperatures using remote sensing technology is examined in a shrub-steppe ecosystem. The emissivities of Artemisia tridentata L. shrubs and the soil surface were examined in such an ecosystem. The emissivity of A. tridentata plants was calculated to be 0.97, which is in the range of reported values for other green plants. The soil emissivity was 0.93. Temperature readings from an infrared thermometer (IRT) must be corrected for the emissivity value of the target and the reflected sky radiation. Although these two factors produce errors which are opposite in sign, they will not offset one another. An analysis is presented which quantifies the temperature error resulting from ignoring the corrections. The error is negligible only for emissivity values greater than 0.98. The error is proportional to temperature, and increases rapidly with decreases in emissivity. The true emissivities must be determined, and the above corrections must be calculated in order to obtain accurate temperatures in an ecosystem from remote sensing methods. (author)

The infrared emissivities of soil and Artemisia tridentata and subsequent temperature corrections in a shrub-steppe ecosystem

International Nuclear Information System (INIS)

Hipps, L.E.

1989-01-01

The determination of plant and soil temperatures using remote sensing technology is examined in a shrub-steppe ecosystem. The emissivities of Artemisia tridentata L. shrubs and the soil surface were examined in such an ecosystem. The emissivity of A. tridentata plants was calculated to be 0.97, which is in the range of reported values for other green plants. The soil emissivity was 0.93. Temperature readings from an infrared thermometer (IRT) must be corrected for the emissivity value of the target and the reflected sky radiation. Although these two factors produce errors which are opposite in sign, they will not offset one another. An analysis is presented which quantifies the temperature error resulting from ignoring the corrections. The error is negligible only for emissivity values greater than 0.98. The error is proportional to temperature, and increases rapidly with decreases in emissivity. The true emissivities must be determined, and the above corrections must be calculated in order to obtain accurate temperatures in an ecosystem from remote sensing methods

Hyperbolic projections of siemens 3d-mlc leaf paths

International Nuclear Information System (INIS)

Menzies, N.

2004-01-01

Full text: The Siemens Primus linear accelerator has the option of being fitted with a multi-leaf collimator (3D-MLC) that is marketed as having 'double focus', to achieve a constant dose penumbra for all leaf settings. This is achieved by moving the leaves through arcs (similar to some conventional collimator jaws), as well as shaping the leaf side-faces as divergent planes from the x-ray source. One consequence of the mechanical design of the 3D-MLC is that as individual leaves are moved, their projections from the light / x-ray source to the treatment plane follow paths that are hyperbolic, as shown in the figure below. (The eccentricity of the hyperbola is a function of leaf number / distance from centre.) The trajectories of the MLC leaves were modelled (in a spreadsheet) using geometrical projections of the MLC leaves to the treatment plane, with construction details provided in Siemens documentation. The results were checked against the image of the leaf in the linac light field. This problem belongs to the class of conic sections in mathematics, where the intersection of a plane with both nappes of a double right circular cone results in a hyperbola. The good agreement between the model and the light field image provided confirmation of the MLC construction details. AS/NZS 4434.1:1996 (reproduced from IEC 976:1989) provides specifications for maximum deviation from orthogonality of adjacent edges, which can be interpreted for MLC collimators to parallelism of the direction of leaf travel and the adjacent collimator edge (e.g. Elekta ATS). However for the Siemens 'double focused' MLC, it is demonstrated that the geometrical construction of the MLC militates against the leaf image being used for this kind of test. It is also demonstrated that at last one commercial treatment planning system models the Siemens leaf trajectories linearly. The clinical significance of the error in this model is shown to be negligible. Copyright (2004) Australasian College of

Role of soil-to-leaf tritium transfer in controlling leaf tritium dynamics: Comparison of experimental garden and tritium-transfer model results.

Science.gov (United States)

Ota, Masakazu; Kwamena, Nana-Owusua A; Mihok, Steve; Korolevych, Volodymyr

2017-11-01

Environmental transfer models assume that organically-bound tritium (OBT) is formed directly from tissue-free water tritium (TFWT) in environmental compartments. Nevertheless, studies in the literature have shown that measured OBT/HTO ratios in environmental samples are variable and generally higher than expected. The importance of soil-to-leaf HTO transfer pathway in controlling the leaf tritium dynamics is not well understood. A model inter-comparison of two tritium transfer models (CTEM-CLASS-TT and SOLVEG-II) was carried out with measured environmental samples from an experimental garden plot set up next to a tritium-processing facility. The garden plot received one of three different irrigation treatments - no external irrigation, irrigation with low tritium water and irrigation with high tritium water. The contrast between the results obtained with the different irrigation treatments provided insights into the impact of soil-to-leaf HTO transfer on the leaf tritium dynamics. Concentrations of TFWT and OBT in the garden plots that were not irrigated or irrigated with low tritium water were variable, responding to the arrival of the HTO-plume from the tritium-processing facility. In contrast, for the plants irrigated with high tritium water, the TFWT concentration remained elevated during the entire experimental period due to a continuous source of high HTO in the soil. Calculated concentrations of OBT in the leaves showed an initial increase followed by quasi-equilibration with the TFWT concentration. In this quasi-equilibrium state, concentrations of OBT remained elevated and unchanged despite the arrivals of the plume. These results from the model inter-comparison demonstrate that soil-to-leaf HTO transfer significantly affects tritium dynamics in leaves and thereby OBT/HTO ratio in the leaf regardless of the atmospheric HTO concentration, only if there is elevated HTO concentrations in the soil. The results of this work indicate that assessment models

Automated rice leaf disease detection using color image analysis

Science.gov (United States)

Pugoy, Reinald Adrian D. L.; Mariano, Vladimir Y.

2011-06-01

In rice-related institutions such as the International Rice Research Institute, assessing the health condition of a rice plant through its leaves, which is usually done as a manual eyeball exercise, is important to come up with good nutrient and disease management strategies. In this paper, an automated system that can detect diseases present in a rice leaf using color image analysis is presented. In the system, the outlier region is first obtained from a rice leaf image to be tested using histogram intersection between the test and healthy rice leaf images. Upon obtaining the outlier, it is then subjected to a threshold-based K-means clustering algorithm to group related regions into clusters. Then, these clusters are subjected to further analysis to finally determine the suspected diseases of the rice leaf.

Strigolactone Regulates Leaf Senescence in Concert with Ethylene in Arabidopsis.

Science.gov (United States)

Ueda, Hiroaki; Kusaba, Makoto

2015-09-01

Leaf senescence is not a passive degenerative process; it represents a process of nutrient relocation, in which materials are salvaged for growth at a later stage or to produce the next generation. Leaf senescence is regulated by various factors, such as darkness, stress, aging, and phytohormones. Strigolactone is a recently identified phytohormone, and it has multiple functions in plant development, including repression of branching. Although strigolactone is implicated in the regulation of leaf senescence, little is known about its molecular mechanism of action. In this study, strigolactone biosynthesis mutant strains of Arabidopsis (Arabidopsis thaliana) showed a delayed senescence phenotype during dark incubation. The strigolactone biosynthesis genes MORE AXIALLY GROWTH3 (MAX3) and MAX4 were drastically induced during dark incubation and treatment with the senescence-promoting phytohormone ethylene, suggesting that strigolactone is synthesized in the leaf during leaf senescence. This hypothesis was confirmed by a grafting experiment using max4 as the stock and Columbia-0 as the scion, in which the leaves from the Columbia-0 scion senesced earlier than max4 stock leaves. Dark incubation induced the synthesis of ethylene independent of strigolactone. Strigolactone biosynthesis mutants showed a delayed senescence phenotype during ethylene treatment in the light. Furthermore, leaf senescence was strongly accelerated by the application of strigolactone in the presence of ethylene and not by strigolactone alone. These observations suggest that strigolactone promotes leaf senescence by enhancing the action of ethylene. Thus, dark-induced senescence is regulated by a two-step mechanism: induction of ethylene synthesis and consequent induction of strigolactone synthesis in the leaf. © 2015 American Society of Plant Biologists. All Rights Reserved.

Computer aided FEA simulation of EN45A parabolic leaf spring

Directory of Open Access Journals (Sweden)

Krishan Kumar

2013-04-01

Full Text Available This paper describes computer aided finite element analysis of parabolic leaf spring. The present work is an improvement in design of EN45A parabolic leaf spring used by a light commercial automotive vehicle. Development of a leaf spring is a long process which requires lots of test to validate the design and manufacturing variables. A three-layer parabolic leaf spring of EN45A has been taken for this work. The thickness of leaves varies from center to the outer side following a parabolic pattern. These leaf springs are designed to become lighter, but also provide a much improved ride to the vehicle through a reduction on interleaf friction. The CAD modeling of parabolic leaf spring has been done in CATIA V5 and for analysis the model is imported in ANSYS-11 workbench. The finite element analysis (FEA of the leaf spring has been carried out by initially discretizing the model into finite number of elements and nodes and then applying the necessary boundary conditions. Maximum displacement, directional displacement, equivalent stress and weight of the assembly are the output targets of this analysis for comparison & validation of the work.

Correlated evolution of stem and leaf hydraulic traits in Pereskia (Cactaceae).

Science.gov (United States)

Edwards, Erika J

2006-01-01

Recent studies have demonstrated significant correlations between stem and leaf hydraulic properties when comparing across species within ecological communities. This implies that these traits are co-evolving, but there have been few studies addressing plant water relations within an explicitly evolutionary framework. This study tests for correlated evolution among a suite of plant water-use traits and environmental parameters in seven species of Pereskia (Cactaceae), using phylogenetically independent contrasts. There were significant evolutionary correlations between leaf-specific xylem hydraulic conductivity, Huber Value, leaf stomatal pore index, leaf venation density and leaf size, but none of these traits appeared to be correlated with environmental water availability; only two water relations traits - mid-day leaf water potentials and photosynthetic water use efficiency - correlated with estimates of moisture regime. In Pereskia, it appears that many stem and leaf hydraulic properties thought to be critical to whole-plant water use have not evolved in response to habitat shifts in water availability. This may be because of the extremely conservative stomatal behavior and particular rooting strategy demonstrated by all Pereskia species investigated. These results highlight the need for a lineage-based approach to understand the relative roles of functional traits in ecological adaptation.

The leaf phenophase of deciduous species altered by land pavements

Science.gov (United States)

Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

2018-02-01

It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash (Fraxinus chinensis) and maple (Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

[Spectrum Variance Analysis of Tree Leaves Under the Condition of Different Leaf water Content].

Science.gov (United States)

Wu, Jian; Chen, Tai-sheng; Pan, Li-xin

2015-07-01

Leaf water content is an important factor affecting tree spectral characteristics. So Exploring the leaf spectral characteristics change rule of the same tree under the condition of different leaf water content and the spectral differences of different tree leaves under the condition of the same leaf water content are not only the keys of hyperspectral vegetation remote sensing information identification but also the theoretical support of research on vegetation spectrum change as the differences in leaf water content. The spectrometer was used to observe six species of tree leaves, and the reflectivity and first order differential spectrum of different leaf water content were obtained. Then, the spectral characteristics of each tree species leaves under the condition of different leaf water content were analyzed, and the spectral differences of different tree species leaves under the condition of the same leaf water content were compared to explore possible bands of the leaf water content identification by hyperspectral remote sensing. Results show that the spectra of each tree leaf have changed a lot with the change of the leaf water content, but the change laws are different. Leaf spectral of different tree species has lager differences in some wavelength range under the condition of same leaf water content, and it provides some possibility for high precision identification of tree species.

Natural Pineapple Leaf Fibre Extraction On Josapine And Morris

OpenAIRE

Mazalan Muhammad Firdaus; Yusof Yusri

2017-01-01

The pineapple’s leaf plant contains approximately 2.5% to 3.5% of strong white silky fibres. These fibres are useful and can be extracted from the leaves. There are a few ways to extract the fibre such as hand scrapping and by extraction machine. The objective of this research is to study the quality of fibre extraction by using different age of pineapple leaf. Next, the study aims to compare the quality of Josapine and Morris pineapple leaf with tensile test. Fibre yield percentage are calcu...

Leaf processing behaviour in Atta leafcutter ants: 90% of leaf cutting takes place inside the nest, and ants select pieces that require less cutting.

Science.gov (United States)

Garrett, Ryan W; Carlson, Katherine A; Goggans, Matthew Scott; Nesson, Michael H; Shepard, Christopher A; Schofield, Robert M S

2016-01-01

Leafcutter ants cut trimmings from plants, carry them to their underground nests and cut them into smaller pieces before inoculating them with a fungus that serves as a primary food source for the colony. Cutting is energetically costly, so the amount of cutting is important in understanding foraging energetics. Estimates of the cutting density, metres of cutting per square metre of leaf, were made from samples of transported leaf cuttings and of fungal substrate from field colonies of Atta cephalotes and Atta colombica. To investigate cutting inside the nest, we made leaf-processing observations of our laboratory colony, A. cephalotes. We did not observe the commonly reported reduction of the leaf fragments into a pulp, which would greatly increase the energy cost of processing. Video clips of processing behaviours, including behaviours that have not previously been described, are linked. An estimated 2.9 (±0.3) km of cutting with mandibles was required to reduce a square metre of leaf to fungal substrate. Only about 12% (±1%) of this cutting took place outside of the nest. The cutting density and energy cost is lower for leaf material with higher ratios of perimeter to area, so we tested for, and found that the laboratory ants had a preference for leaves that were pre-cut into smaller pieces. Estimates suggest that the energy required to transport and cut up the leaf material is comparable to the metabolic energy available from the fungus grown on the leaves, and so conservation of energy is likely to be a particularly strong selective pressure for leafcutter ants.

QTL mapping of flag leaf-related traits in wheat (Triticum aestivum L.).

Science.gov (United States)

Liu, Kaiye; Xu, Hao; Liu, Gang; Guan, Panfeng; Zhou, Xueyao; Peng, Huiru; Yao, Yingyin; Ni, Zhongfu; Sun, Qixin; Du, Jinkun

2018-04-01

QTL controlling flag leaf length, flag leaf width, flag leaf area and flag leaf angle were mapped in wheat. This study aimed to advance our understanding of the genetic mechanisms underlying morphological traits of the flag leaves of wheat (Triticum aestivum L.). A recombinant inbred line (RIL) population derived from ND3331 and the Tibetan semi-wild wheat Zang1817 was used to identify quantitative trait loci (QTLs) controlling flag leaf length (FLL), flag leaf width (FLW), flag leaf area (FLA), and flag leaf angle (FLANG). Using an available simple sequence repeat genetic linkage map, 23 putative QTLs for FLL, FLW, FLA, and FLANG were detected on chromosomes 1B, 2B, 3A, 3D, 4B, 5A, 6B, 7B, and 7D. Individual QTL explained 4.3-68.52% of the phenotypic variance in different environments. Four QTLs for FLL, two for FLW, four for FLA, and five for FLANG were detected in at least two environments. Positive alleles of 17 QTLs for flag leaf-related traits originated from ND3331 and 6 originated from Zang1817. QTLs with pleiotropic effects or multiple linked QTL were also identified on chromosomes 1B, 4B, and 5A; these are potential target regions for fine-mapping and marker-assisted selection in wheat breeding programs.

Evaluation of leaf energy dissipation by the Photochemical Reflectance

Science.gov (United States)

Raddi, S.; Magnani, F.

Starting from the early paper by Heber (1969), several studies have demonstrated a subtle shift in leaf spectroscopic characteristics (both absorbance and reflectance) in response to rapid changes in environmental conditions. More recent work, briefly reviewed here, has also demonstrated the existence of two components in the maked peak centered at 505-540 nm: an irreversible component, attributed to the interconversion of leaf xanthophylls, and a reversible component at slightly longer wavelengths, resulting from conformational changes induced by the buildup of a pH gradient across the thylakoid membrane associated with photosynthetic electron transport. Both processes (xanthophyll de-epoxidation and conformational changes) are known to contribute to the dissipation of excess energy in Photosystem II (PSII). Leaf spectroscopy could therefore provide a powerful non-invasive tool for the determination of leaf photosynthetic processes. This led to the development of the normalized spectral index PRI (Photochemical Reflectance Index; Gamon, Penuelas &Field 1992; Gamon, Serrano &Surfus 1997), which relates the functional signal at 531 nm to a reference signal at 570 nm. The index has been found to track diurnal changes in xanthophyll de-epoxidation state, radiation use efficiency and fluorescence in response to light, both at the leaf and more recently at the canopy level. A common relationship has also beenreported across species and functional types, although such a generality has not always been confirmed. Recent reports (Stylinski et al. 2000) have also hinted of a possible link between PRI and leaf photosynthetic potential, possibly through the correlation between xanthophyll content and electron transport machinery in the chloroplast. Such a link, if confirmed, could prove very useful for the remote sensing and modelling ofvegetation. Some of these open questions were addressed in the present study. The correlation between leaf function and reflectance was

Translational researches on leaf senescence for enhancing plant productivity and quality.

Science.gov (United States)

Guo, Yongfeng; Gan, Su-Sheng

2014-07-01

Leaf senescence is a very important trait that limits yield and biomass accumulation of agronomic crops and reduces post-harvest performance and the nutritional value of horticultural crops. Significant advance in physiological and molecular understanding of leaf senescence has made it possible to devise ways of manipulating leaf senescence for agricultural improvement. There are three major strategies in this regard: (i) plant hormone biology-based leaf senescence manipulation technology, the senescence-specific gene promoter-directed IPT system in particular; (ii) leaf senescence-specific transcription factor biology-based technology; and (iii) translation initiation factor biology-based technology. Among the first strategy, the P SAG12 -IPT autoregulatory senescence inhibition system has been widely explored and successfully used in a variety of plant species for manipulating senescence. The vast majority of the related research articles (more than 2000) showed that crops harbouring the autoregulatory system displayed a significant delay in leaf senescence without any abnormalities in growth and development, a marked increase in grain yield and biomass, dramatic improvement in horticultural performance, and/or enhanced tolerance to drought stress. This technology is approaching commercialization. The transcription factor biology-based and translation initiation factor biology-based technologies have also been shown to be very promising and have great potentials for manipulating leaf senescence in crops. Finally, it is speculated that technologies based on the molecular understanding of nutrient recycling during leaf senescence are highly desirable and are expected to be developed in future translational leaf senescence research. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Titan Lifting Entry & Atmospheric Flight (T-LEAF) Science Mission

Science.gov (United States)

Lee, G.; Sen, B.; Ross, F.; Sokol, D.

2016-12-01

Northrop Grumman has been developing the Titan Lifting Entry & Atmospheric Flight (T-LEAF) sky rover to roam the lower atmosphere and observe at close quarters the lakes and plains of Saturn's ocean moon, Titan. T-LEAF also supports surface exploration and science by providing precision delivery of in-situ instruments to the surface of Titan. T-LEAF is a highly maneuverable sky rover and its aerodynamic shape (i.e., a flying wing) does not restrict it to following prevailing wind patterns on Titan, but allows mission operators to chart its course. This freedom of mobility allows T-LEAF to follow the shorelines of Titan's methane lakes, for example, or to target very specific surface locations. We will present a straw man concept of T-LEAF, including size, mass, power, on-board science payloads and measurement, and surface science dropsonde deployment CONOPS. We will discuss the various science instruments and their vehicle level impacts, such as meteorological and electric field sensors, acoustic sensors for measuring shallow depths, multi-spectral imagers, high definition cameras and surface science dropsondes. The stability of T-LEAF and its long residence time on Titan will provide for time to perform a large aerial survey of select prime surface targets deployment of dropsondes at selected locations surface measurements that are coordinated with on-board remote measurements communication relay capabilities to orbiter (or Earth). In this context, we will specifically focus upon key factors impacting the design and performance of T-LEAF science: science payload accommodation, constraints and opportunities characteristics of flight, payload deployment and measurement CONOPS in the Titan atmosphere. This presentation will show how these factors provide constraints as well as enable opportunities for novel long duration scientific studies of Titan's surface.

Butterfly Learning and the Diversification of Plant Leaf Shape

Directory of Open Access Journals (Sweden)

Denise Dalbosco Dell'aglio

2016-07-01

Full Text Available Visual cues are important for insects to find flowers and host plants. It has been proposed that the diversity of leaf shape in Passiflora vines could be a result of negative frequency dependent selection driven by visual searching behavior among their butterfly herbivores. Here we tested the hypothesis that Heliconius butterflies use leaf shape as a cue to initiate approach towards a host plant. We first tested for the ability to recognize shapes using a food reward conditioning experiment. Butterflies showed an innate preference for flowers with three and five petals. However, they could be trained to increase the frequency of visits to a non-preferred flower with two petals, indicating an ability to learn to associate shape with a reward. Next we investigated shape learning specifically in the context of oviposition by conditioning females to lay eggs on two shoots associated with different artificial leaf shapes: their own host plant, Passiflora biflora, and a lanceolate non-biflora leaf shape. The conditioning treatment had a significant effect on the approach of butterflies to the two leaf shapes, consistent with a role for shape learning in oviposition behavior. This study is the first to show that Heliconius butterflies use shape as a cue for feeding and oviposition, and can learn shape preference for both flowers and leaves. This demonstrates the potential for Heliconius to drive negative frequency dependent selection on the leaf shape of their Passiflora host plants.

Gamma irradiation enhances biological activities of mulberry leaf extract

International Nuclear Information System (INIS)

Cho, Byoung-Ok; Che, Denis Nchang; Yin, Hong-Hua; Jang, Seon-Il

2017-01-01

The purpose of this study was to investigate the influence of irradiation on the anti-oxidative, anti-inflammatory and whitening effects of mulberry leaf extract. This was done by comparing the phenolic contents; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effects; 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) radical scavenging effects; in vitro tyrosinase inhibitory effects and the production of IL-6, TNF-α, PGE 2 , and NO in lipopolysaccharide-stimulated RAW264.7 macrophages and the production of IL-6 and TNF-α in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated HMC-1 cells, respectively. The results showed that irradiated mulberry leaf extract possesses more anti-oxidant, anti-inflammatory, and tyrosinase inhibitory activities than their non-irradiated counterpart, probably due to increase in phenolic contents induced by gamma irradiation at dose of 10kGy. This research stresses on the importance of irradiation in functional foods. - Highlights: • Gamma-irradiated mulberry leaf extract enhanced in vitro antioxidant activities. • Gamma-irradiated mulberry leaf extract enhanced in vitro tyrosinase inhibitory effects. • Gamma-irradiated mulberry leaf extract treatment reduced the production of IL-6, TNF-α, PGE 2 , and NO.

Ecophysiological function of leaf 'windows' in Lithops species - 'Living Stones' that grow underground.

Science.gov (United States)

Martin, C E; Brandmeyer, E A; Ross, R D

2013-01-01

Leaf temperatures were lower when light entry at the leaf tip window was prevented through covering the window with reflective tape, relative to leaf temperatures of plants with leaf tip windows covered with transparent tape. This was true when leaf temperatures were measured with an infrared thermometer, but not with a fine-wire thermocouple. Leaf tip windows of Lithops growing in high-rainfall regions of southern Africa were larger than the windows of plants (numerous individuals of 17 species) growing in areas with less rainfall and, thus, more annual insolation. The results of this study indicate that leaf tip windows of desert plants with an underground growth habit can allow entry of supra-optimal levels of radiant energy, thus most likely inhibiting photosynthetic activity. Consequently, the size of the leaf tip windows correlates inversely with habitat solar irradiance, minimising the probability of photoinhibition, while maximising the absorption of irradiance in cloudy, high-rainfall regions. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

Comparison of gold leaf thickness in Namban folding screens using X-ray fluorescence

Energy Technology Data Exchange (ETDEWEB)

Pessanha, Sofia; Madeira, Teresa I.; Manso, Marta [Centro de Fisica Atomica da Universidade de Lisboa, Lisbon (Portugal); Guerra, Mauro; Carvalho, Maria Luisa [Centro de Fisica Atomica da Universidade de Lisboa, Lisbon (Portugal); Universidade Nova de Lisboa, Departamento de Fisica, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Gac, Agnes le [Centro de Fisica Atomica da Universidade de Lisboa, Lisbon (Portugal); Universidade Nova de Lisboa, Departamento de Conservacao e Restauro, Faculdade de Ciencias e Tecnologia, Caparica (Portugal)

2014-09-15

In this work, the thickness of the gold leaf applied in six Japanese folding screens is compared using a nondestructive approach. Four screens belonging to the Momoyama period (∝1573-1603) and two screens belonging to the early Edo period (∝1603-1868) were analyzed in situ using energy dispersive X-ray fluorescence, and the thickness of the applied gold leaf was evaluated using a methodology based on the attenuation of the different characteristic lines of gold in the gold leaf layer. Considering that the leaf may well not be made of pure gold, we established that, for the purpose of comparing the intensity ratios of the Au lines, layers made with gold leaf of high grade can be considered identical. The gold leaf applied in one of the screens from the Edo period was found to be thinner than the gold leaf applied in the other ones. This is consistent with the development of the beating technology to obtain ever more thin gold leafs. (orig.)

Comparison of gold leaf thickness in Namban folding screens using X-ray fluorescence

International Nuclear Information System (INIS)

Pessanha, Sofia; Madeira, Teresa I.; Manso, Marta; Guerra, Mauro; Carvalho, Maria Luisa; Gac, Agnes le

2014-01-01

In this work, the thickness of the gold leaf applied in six Japanese folding screens is compared using a nondestructive approach. Four screens belonging to the Momoyama period (∝1573-1603) and two screens belonging to the early Edo period (∝1603-1868) were analyzed in situ using energy dispersive X-ray fluorescence, and the thickness of the applied gold leaf was evaluated using a methodology based on the attenuation of the different characteristic lines of gold in the gold leaf layer. Considering that the leaf may well not be made of pure gold, we established that, for the purpose of comparing the intensity ratios of the Au lines, layers made with gold leaf of high grade can be considered identical. The gold leaf applied in one of the screens from the Edo period was found to be thinner than the gold leaf applied in the other ones. This is consistent with the development of the beating technology to obtain ever more thin gold leafs. (orig.)

Gold leaf counter electrodes for dye-sensitized solar cells

Science.gov (United States)

Shimada, Kazuhiro; Toyoda, Takeshi

2018-03-01

In this study, a gold leaf 100 nm thin film is used as the counter electrode in dye-sensitized solar cells. The traditional method of hammering gold foil to obtain a thin gold leaf, which requires only small amounts of gold, was employed. The gold leaf was then attached to the substrate using an adhesive to produce the gold electrode. The proposed approach for fabricating counter electrodes is demonstrated to be facile and cost-effective, as opposed to existing techniques. Compared with electrodes prepared with gold foil and sputtered gold, the gold leaf counter electrode demonstrates higher catalytic activity with a cobalt-complex electrolyte and higher cell efficiency. The origin of the improved performance was investigated by surface morphology examination (scanning electron microscopy), various electrochemical analyses (cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy), and crystalline analysis (X-ray diffractometry).

Novel fungal disease in complex leaf-cutting ant societies

DEFF Research Database (Denmark)

Hughes, David Peter; Evans, Harry C.; Hywel-Jones, Nigel

2009-01-01

1. The leaf-cutting ants practise an advanced system of mycophagy where they grow a fungus as a food source. As a consequence of parasite threats to their crops, they have evolved a system of morphological, behavioural, and chemical defences, particularly against fungal pathogens (mycopathogens). 2....... Specific fungal diseases of the leaf-cutting ants themselves have not been described, possibly because broad spectrum anti-fungal defences against mycopathogens have reduced their susceptibility to entomopathogens. 3. Using morphological and molecular tools, the present study documents three rare infection...... events of Acromyrmex and Atta leaf-cutting ants by Ophiocordyceps fungi, agenus of entomopathogens that is normally highly specific in its host choice. 4. As leaf-cutting ants have been intensively studied, the absence of prior records of Ophiocordyceps suggests that these infections may be a novel event...

Isolation and partial characterization of an acid phosphatase from Artemisia vulgaris pollen extract

Directory of Open Access Journals (Sweden)

RATKO M. JANKOV

2002-09-01

Full Text Available An acid phosphatase from an extract of mugwort (Artemisia vulgaris pollen was purified by a factor of 48 by a combination of ion exchange and gel-chromatography. The molecular weights of the enzyme were 76 kDa and 73 kDa, determined by gel filtration on a Sephadex G-100 sf column and by SDS PAGE (under reducing and non-reducing conditions, respectively. In analytical isoelectrofocusing, the enzyme appears as two very close bands, pI at about 4.2. The optimum pH for the enzyme is 5.4. The apparent Km for p-nitrophenyl phosphate was estimated to be 0.16 mM. The purified enzyme has broad specificity, and hydrolyses p-nitrophenyl phosphate and a-naphthyl phosphate. Pyrophosphate and O-phospho-L-tyrosine were estimated to be the best substrates for this enzyme as potential in vivo substrates. The enzyme is inhibited competitively by phosphate (Ki = 1.25 mM, molybdate (Ki = 0.055 mM and pyrophosphate (Ki = 6.7 mM and non-competitively by fluoride (Ki = 9.8 mM. Metal ions such as Hg2+, Cu2+ and Zn2+ express an inhibitory effect on the enzyme, while the enzyme is slightly activated by non-ionic detergents, Tween 20 and Triton X-100. There is no change in the enzyme activity in the presence of tartrate, citrate, EDTA, 1,10-phenanthroline and sulfhydryl-group modifiers such as p-chloromercuribenzoate and N-ethylmaleimide.

Cytotoxic Properties of Three Isolated Coumarin-hemiterpene Ether Derivatives from Artemisia armeniaca Lam.

Science.gov (United States)

Mojarrab, Mahdi; Emami, Seyed Ahmad; Delazar, Abbas; Tayarani-Najaran, Zahra

2017-01-01

Considering multiple reports on cytotoxic activity of the Artemisia genus and its phytochemicals, in the current study A. armeniaca Lam. and the three components isolated from the plant were subjected to cytotoxic studies. Analytical fractionation of A. armeniaca aerial parts for the first time was directed to the isolation of 7-hydroxy-8-(4-hydroxy-3-methylbutoxy) comarin (armenin), 8-hydroxy-7-(4-hydroxy-3-methylbutoxy) comarin (isoarmenin) and deoxylacarol. Cytotoxicity assessed with alamalBlue® assay and apoptosis was detected by PI staining and western blot analysis of Bax and PARP proteins. Extracts and all compounds exhibited cytotoxic activity against apoptosis-proficient HL-60 and apoptosis-resistant K562 cells, with the lowest cytotoxic activity on J774 cell line as non-malignant cell. Armenin as the most potent component decreased the viability of cell with IC50 of 22.5 and 71.1 µM for K562 and HL-60 cells respectively and selected for further mechanistic study. Armenin increased the sub-G1 peak in flow cytometry histogram of HL-60 and K562 treated cells and increase in the amount of Bax protein and the cleavage of PARP in comparison with the control after treatment for 48 h in K562 treated cells verified the apoptotic activity of the armenin. Taken together, according to the finding of this study armenin was introduced as a novel cytotoxic compound with apoptotic activity, which is encouraging for further mechanistic and clinical studies.

Radioprotection of Swiss albino mice by Adhatoda vesica leaf extract

International Nuclear Information System (INIS)

Kumar, A.

2003-01-01

Full text: The radioprotective role of aqueous extract of Adhatoda vesica leaf extract against radiation induced hematological alterations in peripheral blood of Swiss albino mice was studied at various post-irradiation intervals between 6 hrs to 30 days. Oral administration of Adhatoda vesica leaf extract (800 mg / kg body weight) prior to whole-body irradiation showed a significant protection in terms of survival percentage and hematological parameters. Mice exposed to radiation (8 Gy) without Adhatoda vesica leaf extract pre-treatment exhibited signs of radiation sickness like anorexia, lethargicity, ruffled hairs and diarrhoea and such animals died within 26 days post-irradiation. The dose reduction factor (DRF=1.6) for Adhatoda vesica leaf extract was calculated from LD50/30 values. A significant decline in hematological constituents (RBCs, WBCs, Hb and Hct) was evident till day 15, at later period of observation (day 15 onwards), no animals could survive from control group whereas, in Adhatoda vesica leaf extract pre-treated irradiated group, a gradual recovery was noted in the hematological values. However, these hematological values remained significantly below the normal even till day 30. A significant decrease in GSH was recorded in control animals. Experimental animals showed a significant increase in GSH content (blood as well as liver) with respect to control, but such values remained below normal. A significant increase in TBARS level in liver and serum was evident in control animals. Although, no significant difference was noticed in such levels in normal and Adhatoda vesica leaf extract treated animals. But, a significant decrease was registered in Adhatoda vesica leaf extract pretreated irradiated animals. The results from the present study suggest that Adhatoda vesica leaf extract has radioprotective role in stimulating/protecting the hematopoietic system thereby enhancing the survival and increasing the hematological constituents in peripheral

Leaf and stem morphoanatomy of Petiveria alliacea.

Science.gov (United States)

Duarte, M R; Lopes, J F

2005-12-01

Petiveria alliacea is a perennial herb native to the Amazonian region and used in traditional medicine for different purposes, such as diuretic, antispasmodic and anti-inflammatory. The morphoanatomical characterization of the leaf and stem was carried out, in order to contribute to the medicinal plant identification. The plant material was fixed, freehand sectioned and stained either with toluidine blue or astra blue and basic fuchsine. Microchemical tests were also applied. The leaf is simple, alternate and elliptic. The blade exhibits paracytic stomata on the abaxial side, non-glandular trichomes and dorsiventral mesophyll. The midrib is biconvex and the petiole is plain-convex, both traversed by collateral vascular bundles adjoined with sclerenchymatic caps. The stem, in incipient secondary growth, presents epidermis, angular collenchyma, starch sheath and collateral vascular organization. Several prisms of calcium oxalate are seen in the leaf and stem.

Leaf morphophysiology of a Neotropical mistletoe is shaped by seasonal patterns of host leaf phenology.

Science.gov (United States)

Scalon, Marina Corrêa; Rossatto, Davi Rodrigo; Domingos, Fabricius Maia Chaves Bicalho; Franco, Augusto Cesar

2016-04-01

Several mistletoe species are able to grow and reproduce on both deciduous and evergreen hosts, suggesting a degree of plasticity in their ability to cope with differences in intrinsic host functions. The aim of this study was to investigate the influence of host phenology on mistletoe water relations and leaf gas exchange. Mistletoe Passovia ovata parasitizing evergreen (Miconia albicans) hosts and P. ovata parasitizing deciduous (Byrsonima verbascifolia) hosts were sampled in a Neotropical savanna. Photosynthetic parameters, diurnal cycles of stomatal conductance, pre-dawn and midday leaf water potential, and stomatal anatomical traits were measured during the peak of the dry and wet seasons, respectively. P. ovata showed distinct water-use strategies that were dependent on host phenology. For P. ovata parasitizing the deciduous host, water use efficiency (WUE; ratio of photosynthetic rate to transpirational water loss) was 2-fold lower in the dry season than in the wet season; in contrast, WUE was maintained at the same level during the wet and dry seasons in P. ovata parasitizing the evergreen host. Generally, mistletoe and host diurnal cycles of stomatal conductance were linked, although there were clear differences in leaf water potential, with mistletoe showing anisohydric behaviour and the host showing isohydric behaviour. Compared to mistletoes attached to evergreen hosts, those parasitizing deciduous hosts had a 1.4-fold lower stomatal density and 1.2-fold wider stomata on both leaf surfaces, suggesting that the latter suffered less intense drought stress. This is the first study to show morphophysiological differences in the same mistletoe species parasitizing hosts of different phenological groups. Our results provide evidence that phenotypical plasticity (anatomical and physiological) might be essential to favour the use of a greater range of hosts.

7 CFR 29.2438 - Thin Leaf (C Group).

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Thin Leaf (C Group). 29.2438 Section 29.2438... REGULATIONS TOBACCO INSPECTION Standards Grades § 29.2438 Thin Leaf (C Group). This group consists of leaves... body than those of the B group, and show little or no ground injury. Choice- and fine-quality tobacco...

7 CFR 29.1163 - Smoking Leaf (H Group).

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Smoking Leaf (H Group). 29.1163 Section 29.1163... REGULATIONS TOBACCO INSPECTION Standards Grades § 29.1163 Smoking Leaf (H Group). This group consists of leaves normally grown at or above the midportion of the stalk. Leaves of the H group show a high degree...

Determining past leaf-out times of New England's deciduous forests from herbarium specimens.

Science.gov (United States)

Everill, Peter H; Primack, Richard B; Ellwood, Elizabeth R; Melaas, Eli K

2014-08-01

• There is great interest in studying leaf-out times of temperate forests because of the importance of leaf-out in controlling ecosystem processes, especially in the face of a changing climate. Remote sensing and modeling, combined with weather records and field observations, are increasing our knowledge of factors affecting variation in leaf-out times. Herbarium specimens represent a potential new source of information to determine whether the variation in leaf-out times observed in recent decades is comparable to longer time frames over past centuries.• Here we introduce the use of herbarium specimens as a method for studying long-term changes in leaf-out times of deciduous trees. We collected historical leaf-out data for the years 1834-2008 from common deciduous trees in New England using 1599 dated herbarium specimens with young leaves.• We found that leaf-out dates are strongly affected by spring temperature, with trees leafing out 2.70 d earlier for each degree C increase in mean April temperature. For each degree C increase in local temperature, trees leafed out 2.06 d earlier. Additionally, the mean response of leaf-out dates across all species and sites over time was 0.4 d earlier per decade. Our results are of comparable magnitude to results from studies using remote sensing and direct field observations.• Across New England, mean leaf-out dates varied geographically in close correspondence with those observed in studies using satellite data. This study demonstrates that herbarium specimens can be a valuable source of data on past leaf-out times of deciduous trees. © 2014 Botanical Society of America, Inc.