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951.
József Garay Zoltán Sebestyén Zoltán Varga Manuel Gámez Alejandro Torres José E. Belda Tomás Cabello 《Journal of pest science》2015,88(2):343-358
Over the last few decades, important advances have been made in understanding of host–parasitoid relations and their applications to biological pest control. Not only has the number of agent species increased, but new manipulation techniques for natural enemies have also been empirically introduced, particularly in greenhouse crops. This makes biocontrol more complex, requiring a new mathematical modeling approach appropriate for the optimization of the release of agents. The present paper aimed at filling this gap by the development of a temperature- and stage-dependent dynamic mathematical model of the host–parasitoid system with an improved functional response. The model is appropriate not only for simulation analysis of the efficiency of biocontrol agents, but also for the application of optimal control methodology for the optimal timing of agent releases, and for the consideration of economic implications. Based on both laboratory and greenhouse trials, the model was validated and fitted to the data of Chelonus oculator (F.) (Hym.: Braconidae) as a biological control agent against the beet armyworm, Spodoptera exigua Hübner (Lep.: Noctuidae). We emphasize that this model can be easily adapted to other interacting species involved in biological or integrated pest control with either parasitoid or predator agents. 相似文献
952.
Gutiérrez A Rodríguez IM Del Río JC 《Journal of agricultural and food chemistry》2004,52(15):4764-4773
The chemical composition of lignin and lipids of bast fibers from kenaf (Hibiscus cannabinus) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with a high syringyl/guaiacyl ratio (5.4) and minor amounts of p-hydroxyphenyl units. Simultaneously, sinapyl and coniferyl acetates were also identified, indicating that this lignin is partially acetylated. p-Hydroxycinnamic acids were found in only trace amounts. The main lipids identified by GC/MS of extracts from kenaf fibers were series of long-chain n-fatty acids, waxes, n-alkanes, and n-fatty alcohols. Free and esterified sterols and triterpenols, steroid hydrocarbons, and steroid and triterpenoid ketones, as well as steryl glycosides, were also found. Finally, the fate of the main constituents of kenaf fibers in alkaline pulping was also investigated. 相似文献
953.
Saiz-Abajo MJ Gonzales-Saiz JM Pizarro C 《Journal of agricultural and food chemistry》2004,52(25):7711-7719
Near-infrared (NIR) spectroscopy was used to discriminate between wine vinegar (red or white) and alcohol vinegar. One orthogonal signal correction method (OSC) was applied on a set of 73 vinegar NIR spectra from both origins and artificial blends made in the laboratory in order to remove information unrelated to a specific chemical response (tartaric acid), which was selected due to its high discriminant ability to differentiate between wine vinegar and alcohol vinegar samples. These corrected NIR spectra, as well as raw NIR spectra and 14 physicochemical variables, were used to develop separate classification models using the potential functions method as a class-modeling technique. The aforementioned models were compared to evaluate the suitability of NIR spectroscopy as a rapid method for discriminating between vinegar origins. The transformation of vinegar NIR spectra by means of an orthogonal signal correction method prompted a notable improvement in the specificity of the constructed classification models. The classification model developed was then applied to artificial vinegar blends made in the laboratory to test its capacity to recognize adulterated vinegar samples. 相似文献
954.
955.
Gianmarco?Mugnai Federico?RossiEmail authorView authors OrcID profile Vincent?John?Martin?Noah?Linus?Felde Claudia?Colesie Burkhard?Büdel Stephan?Peth Aaron?Kaplan Roberto?De?Philippis 《Biology and Fertility of Soils》2018,54(1):27-40
Soil inoculation with cyanobacteria (cyanobacterization) is a biotechnological method widely studied to improve soil quality and productivity. During their growth on soil, cyanobacteria excrete exopolysaccharides (EPSs) which glue trichomes to soil particles, in a three-dimensional extracellular polymeric matrix. EPS productivity is an important screening parameter to select proficient inoculants and is affected by growth conditions and abiotic stresses. In this study, we evaluated the capability of the cyanobacterium Schizothrix cf. delicatissima AMPL0116 to form biocrusts when inoculated in sand microcosms under stressing conditions, and the characteristics of the synthesized polymeric matrix. In parallel, we evaluated the characteristics of exopolysaccharidic exudates of the strain when grown in liquid culture, under optimal growth setting. Our results pointed out at significant differences of the exopolymers produced in the two conditions in terms of monosaccharidic composition and molecular weight distribution, and proved the capability of S. cf. delicatissima AMPL0116 to form stable bioaggregates on sandy soils. 相似文献
956.
Bird schistosomes of wildfowl in the Czech Republic and Poland 总被引:3,自引:0,他引:3
957.
M. G. Luna N. E. Sánchez P. C. Pereyra E. Nieves V. Savino E. Luft E. Virla S. Speranza 《EPPO Bulletin》2012,42(2):260-267
By means of an international project, Argentinian and Italian researchers are carrying out joint research to study biological and ecological aspects of Tuta absoluta biological control. This paper lists indigenous natural enemies reported for T. absoluta, as well as the current results on T. absoluta egg and larval parasitoids in both countries. Parasitoid species that conformed to different guilds are shown to coexist in cropping conditions, and some show positive characteristics as potential biocontrol agents against T. absoluta by means of augmentative releases. Future laboratory and field evaluations of the efficacy of biological control programmes in Argentina and Italy are proposed. 相似文献
958.
The effects of temperature on anatomical and chemical characteristics of Quercus cerris cork were examined. Cork samples were subjected to isothermal air heating between 150 °C and 400 °C and analyzed for mass loss, cellular structure and chemical composition.The thermal decomposition of Q. cerris cork is similar to that of Q. suber cork. Cork is thermally stable below 200 °C and after that degradation depended on temperature and heating time with increasing mass loss, i.e. 3% at 200 °C 10 min and 46% at 350 °C 60 min. With temperature and starting at 200 °C, cells expanded, cell wall thickness was reduced and corrugations were lost.Extractives degraded at lower temperatures, although aliphatic extractives were found to be more stable. Suberin from Q. cerris was more heat resistant than Q. suber suberin, while lignin showed similar resistance.These results provide a basis for studies on the production of Q. cerris bark expanded cork agglomerates for insulation purposes. 相似文献
959.
The Kunitz-type protease inhibitors are the best-characterized family of serine protease inhibitors, probably due to their abundance in several organisms. These inhibitors consist of a chain of ~60 amino acid residues stabilized by three disulfide bridges, and was first observed in the bovine pancreatic trypsin inhibitor (BPTI)-like protease inhibitors, which strongly inhibit trypsin and chymotrypsin. In this review we present the protease inhibitors (PIs) described to date from marine venomous animals, such as from sea anemone extracts and Conus venom, as well as their counterparts in terrestrial venomous animals, such as snakes, scorpions, spiders, Anurans, and Hymenopterans. More emphasis was given to the Kunitz-type inhibitors, once they are found in all these organisms. Their biological sources, specificity against different proteases, and other molecular blanks (being also K+ channel blockers) are presented, followed by their molecular diversity. Whereas sea anemone, snakes and other venomous animals present mainly Kunitz-type inhibitors, PIs from Anurans present the major variety in structure length and number of Cys residues, with at least six distinguishable classes. A representative alignment of PIs from these venomous animals shows that, despite eventual differences in Cys assignment, the key-residues for the protease inhibitory activity in all of them occupy similar positions in primary sequence. The key-residues for the K+ channel blocking activity was also compared. 相似文献
960.
Oualid Haddad Erwan Guyot Nicolas Marinval Fabien Chevalier Lo?c Maillard Latifa Gadi Christelle Laguillier-Morizot Olivier Oudar Angela Sutton Nathalie Charnaux Hanna Hlawaty 《Marine drugs》2015,13(11):6588-6608
Induction of angiogenesis is a potential treatment for chronic ischemia. Low molecular weight fucoidan (LMWF), the sulfated polysaccharide from brown seaweeds, has been shown to promote revascularization in a rat limb ischemia, increasing angiogenesis in vivo. We investigated the potential role of two heparan sulfate (HS) metabolism enzymes, exostosin-2 (EXT2) and heparanase (HPSE), and of two HS-membrane proteoglycans, syndecan-1 and -4 (SDC-1 and SDC-4), in LMWF induced angiogenesis. Our results showed that LMWF increases human vascular endothelial cell (HUVEC) migration and angiogenesis in vitro. We report that the expression and activity of the HS-degrading HPSE was increased after LMWF treatment. The phenotypic tests of LMWF-treated and EXT2- or HPSE-siRNA-transfected cells indicated that EXT2 or HPSE expression significantly affect the proangiogenic potential of LMWF. In addition, LMWF increased SDC-1, but decreased SDC-4 expressions. The effect of LMWF depends on SDC-4 expression. Silencing EXT2 or HPSE leads to an increased expression of SDC-4, providing the evidence that EXT2 and HPSE regulate the SDC-4 expression. Altogether, these data indicate that EXT2, HPSE, and SDC-4 are involved in the proangiogenic effects of LMWF, suggesting that the HS metabolism changes linked to LMWF-induced angiogenesis offer the opportunity for new therapeutic strategies of ischemic diseases. 相似文献