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Communis L. (communi + l)
Kinds of Communis L. Selected AbstractsA PCA-based modelling technique for predicting environmental suitability for organisms from presence recordsDIVERSITY AND DISTRIBUTIONS, Issue 1-2 2001M. P. Robertson We present a correlative modelling technique that uses locality records (associated with species presence) and a set of predictor variables to produce a statistically justifiable probability response surface for a target species. The probability response surface indicates the suitability of each grid cell in a map for the target species in terms of the suite of predictor variables. The technique constructs a hyperspace for the target species using principal component axes derived from a principal components analysis performed on a training dataset. The training dataset comprises the values of the predictor variables associated with the localities where the species has been recorded as present. The origin of this hyperspace is taken to characterize the centre of the niche of the organism. All the localities (grid-cells) in the map region are then fitted into this hyperspace using the values of the predictor variables at these localities (the prediction dataset). The Euclidean distance from any locality to the origin of the hyperspace gives a measure of the ,centrality' of that locality in the hyperspace. These distances are used to derive probability values for each grid cell in the map region. The modelling technique was applied to bioclimatic data to predict bioclimatic suitability for three alien invasive plant species (Lantana camara L., Ricinus communis L. and Solanum mauritianum Scop.) in South Africa, Lesotho and Swaziland. The models were tested against independent test records by calculating area under the curve (AUC) values of receiver operator characteristic (ROC) curves and kappa statistics. There was good agreement between the models and the independent test records. The pre-processing of climatic variable data to reduce the deleterious effects of multicollinearity, and the use of stopping rules to prevent overfitting of the models are important aspects of the modelling process. [source] Elaboration and Validation of a Diagrammatic Scale for Epidemiological Studies of Cercospora Leaf Spot of Castor BeanJOURNAL OF PHYTOPATHOLOGY, Issue 6 2010Wellington Freire Dos Santos Abstract The castor bean cercospora leaf spot (Cercospora ricinella Sacc. & Berl.) is a common disease in castor bean crop (Ricinus communis L.), causing defoliation and losses. In spite of this, the evaluation of disease severity is an important decision support for adoption of strategies and tactics for disease control. Therefore the objective of this work was to elaborate and to validate a diagrammatic to evaluate cercospora leaf spot severity in the castor bean. The scale was developed based on six treatments with different irrigation depths plus the control treatment without irrigation. Based on disease incidence analysis, it was possible to select different severity levels per treatment, which were used to define the percentage intervals of foliar diseased area of the diagrammatic scale. In view of the inexistence of standardized methods for the quantification of cercospora leaf spot in the field, the levels of 0%, 0.1 to 1%, 1.1 to 10%, 10.1 to 20% and 20.1 to 45% of lesioned foliar area were established, pointing out the observation that in the interval of 20 to 45% leaf fall started to occur. The scale was tested according its accuracy, precision and reproducibility. For that, 40 leaves with different disease severity levels were appraised by 10 users, without and with the scale, with an interval of seven days between evaluations of the same users. The appraisers obtained better results under utilization of the scale. The scale proposed in this work presented appropriate applicability for cercospora leaf spot evaluation in castor bean. Higher disease intensity was observed in the control and in treatments with higher irrigation depth and lower irrigation frequency. [source] Organic fertilizers derived from plant materials Part II: Turnover in field trialsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2006Torsten Müller Abstract Our aim was to investigate two different organic fertilizers derived from plant materials (OFDP) with respect to their nitrogen (N) and carbon (C) turnover in field trials planted with small radish (Raphanus sativus L. var. sativus) and white cabbage (Brassica oleracea L. convar. capitata var. alba) or fallow. The two fertilizers investigated were coarse seed meal of yellow lupin (Lupinus luteus L.) and coarse meal of castor cake (Ricinus communis L.). Under cool spring conditions, the soil turnover of yellow lupin,seed meal was slightly enhanced compared to castor-cake meal. During the vegetation period of the vegetables, N added with both fertilizers was metabolized more or less completely by soil microorganisms. Due to similar efficiencies of the fertilizers tested, no significant difference could be found in the N uptake of plants. From this point of view, yellow lupin,seed meal, which can be produced by farmers themselves, has the potential to replace the widely used castor-cake meal. Considerable amounts of N may remain in the field after fertilization with OFDPs either as mineral N or as easily mineralizable organic N. This N should be utilized immediately by a succeeding crop to avoid leaching losses. [source] Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Mateja Colaric Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source] Isolation and characterization of polymorphic microsatellite markers from European pear (Pyrus communis L.)MOLECULAR ECOLOGY RESOURCES, Issue 4 2006F. FERNÁNDEZ-FERNÁNDEZ Abstract This study reports the development and characterization of 19 microsatellite primer pairs developed from genomic DNA of European pear (Pyrus communis) and their transferability to other Pyrus and Malus material. The primers were designed from two different genomic libraries enriched for di- and trinucleotide repeats. When tested in six P. communis cultivars and 15 other Pyrus species, 13 primers revealed single-locus polymorphism and six showed more complex patterns that suggest multiple loci. Two to 18 alleles were detected per locus and two primer pairs were sufficient to discriminate all accessions. Transferability of nine primer pairs to Malus was demonstrated through amplification of discrete products in two accessions. [source] Glutathione S-transferases and malondialdehyde in the liver of NOD mice on short-term treatment with plant mixture extract P-9801091PHYTOTHERAPY RESEARCH, Issue 4 2003R. Petlevski Abstract Changes in the concentration of glutathione S-transferases (GSTs) and malondialdehyde (MDA) were assessed in the liver of normal and diabetic NOD mice with and without treatment with the plant extract P-9801091. The plant extract P-9801091 is an antihyperglycaemic preparation containing Myrtilli folium (Vaccinium myrtillus L.), Taraxaci radix (Taraxacum of,cinale Web.), Cichorii radix (Cichorium intybus L.), Juniperi fructus (Juniperus communis L.) , Centaurii herba (Centaurium umbellatum Gilib.), Phaseoli pericarpium (Phaseolus vulgaris L.), Millefolii herba (Achillea millefolium L.), Mori folium (Morus nigra L.), Valerianae radix (Valeriana of,cinalis L.) and Urticae herba et radix (Urtica dioica L). Hyperglycaemia in diabetes mellitus is responsible for the development of oxidative stress (via glucose auto-oxidation and protein glycation), which is characterized by increased lipid peroxide production (MDA is a lipid peroxidation end product) and/or decreased antioxidative defence (GST in the liver is predominantly an , enzyme, which has antioxidative activity). The catalytic concentration of GSTs in the liver was signi,cantly reduced in diabetic NOD mice compared with normal NOD mice (p < 0.01), while the concentration of MDA showed a rising tendency (not signi,cant). The results showed that statistically signi,cant changes in antioxidative defence occurred in the experimental model of short-term diabetes mellitus. A 7-day treatment with P-9801091 plant extract at a dose of 20 mg/kg body mass led to a signi,cant increase in the catalytic concentration of GSTs in the liver of diabetic NOD mice (p < 0.01) and a decrease in MDA concentration (not signi,cant), which could be explained by its antihyperglycaemic effect. Copyright © 2003 John Wiley & Sons, Ltd. [source] Variation in oxygen isotope fractionation during cellulose synthesis: intramolecular and biosynthetic effectsPLANT CELL & ENVIRONMENT, Issue 10 2006LEONEL STERNBERG ABSTRACT The oxygen isotopic composition of plant cellulose is commonly used for the interpretations of climate, ecophysiology and dendrochronology in both modern and palaeoenvironments. Further applications of this analytical tool depends on our in-depth knowledge of the isotopic fractionations associated with the biochemical pathways leading to cellulose. Here, we test two important assumptions regarding isotopic effects resulting from the location of oxygen in the carbohydrate moiety and the biosynthetic pathway towards cellulose synthesis. We show that the oxygen isotopic fractionation of the oxygen attached to carbon 2 of the glucose moieties differs from the average fractionation of the oxygens attached to carbons 3,6 from cellulose by at least 9%, for cellulose synthesized within seedlings of two different species (Triticum aestivum L. and Ricinus communis L.). The fractionation for a given oxygen in cellulose synthesized by the Triticum seedlings, which have starch as their primary carbon source, is different than the corresponding fractionation in Ricinus seedlings, within which lipids are the primary carbon source. This observation shows that the biosynthetic pathway towards cellulose affects oxygen isotope partitioning, a fact heretofore undemonstrated. Our findings may explain the species-dependent variability in the overall oxygen isotope fractionation during cellulose synthesis, and may provide much-needed insight for palaeoclimate reconstruction using fossil cellulose. [source] Proteomic analysis of core breakdown disorder in Conference pears (Pyrus communis L.)PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 12 2007Romina Pedreschi Abstract 2-DE was applied to study core breakdown disorder in controlled atmosphere stored 'Conference' pears. This physiological disorder is characterized by internal browning of the fruit tissue and the development of cavities. Suitable protein phenol extraction/ammonium acetate-methanol precipitation and 2-DE protocols for a wide pH range were established for pear tissue. The protein expression profiles of healthy, sound (intact tissue of pears with core breakdown) and brown tissue were analyzed with the univariate non-parametric Kolmogorov-Smirnov test and multivariate statistical techniques such as principal component analysis and partial least square discriminant analysis. Both statistical approaches revealed interesting differentially expressed proteins between healthy and disordered pears. LC-ESI-MS/MS identification of differentially expressed proteins between healthy and sound tissue revealed their participation in the energy metabolism, the antioxidant system and ethylene biosynthesis. Up-regulated characteristic proteins in brown tissue were mainly involved in energy metabolism and defense mechanisms. Proteomics coupled to univariate and multivariate statistical techniques seems to be an efficient approach to get a better insight into the different mechanisms and pathways leading to the core breakdown disorder. [source] | |||||||||||||