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891.
Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from March 2004 to July 2005, with six mist-nets, during two nights, using the capture-recapture method. We captured 2970 individuals of 43 bat species. Montane rainforest had the greatest alpha diversity (H′ = 2.681; n = 37), whereas alpha diversity was similar among coffee plantations (H′ = 2.229-2.364; n = 23-26). The number of frugivorous and nectarivorous species was similar among the sites; the greatest exchange in species composition (beta diversity) occurred for insectivorous bats, which reduce their number in coffee plantations as pesticides are incorporated. Bat richness species was significantly related to the number of vegetation strata, height, and cover of trees. We suggest that coffee plantations could act as corridors, facilitating connection among different elements of the landscape in the Sierra Madre de Chiapas for some frugivorous and nectarivorous bats. 相似文献
892.
Nutritional status affects the processes of flowering and fruiting of plants. This study was conducted to determine the effects of fertilizer application on flowering, fruiting, and leaf nutrient content of Vanilla planifolia (Jacks. ex Andr). Treatments consisted of the application of grade 10-20-20 nitrogen, phosphorus, and potassium (NPK) fertilizer to the substratum in annual doses of 20, 50, and 100 g/plant plus a monthly application of foliar fertilizer. Two more treatments were foliar fertilization and no fertilization (control). Treatments increased the number of inflorescences and flower buds per plant, as well as the number and weight of fruits per plant, and decreased the abortion of flowers and immature fruits. These effects depended on the type of fertilizer, the amount applied, and the time of evaluation. The best results were obtained with the 100 g/plant/year treatment with an annual production of 1.5 kg of fruits per plant in the second year. Unfertilized plants produced 0.55 kg/plant/year. Differences were also found in foliar content of N, P, K, and copper (Cu) between vegetative and reproductive branches. Application of fertilizer to the substratum appears to improve reproductive parameters of vanilla plants and the production of beans, while foliar fertilization alone was ineffective in increasing crop productivity. Nutrients also seem to translocate from mature leaves to fruit racemes. 相似文献
893.
Comparative contents of dietary fiber, total phenolics, and minerals in persimmons and apples 总被引:3,自引:0,他引:3
Gorinstein S Zachwieja Z Folta M Barton H Piotrowicz J Zemser M Weisz M Trakhtenberg S Màrtín-Belloso O 《Journal of agricultural and food chemistry》2001,49(2):952-957
Dietary fibers, major phenolics, main minerals, and trace elements in persimmons and apples were analyzed and compared in order to choose a preferable fruit for an antiatherosclerotic diet. Fluorometry and atomic absorption spectrometry following microwave digestion were optimized for the determination of major phenolics and minerals. Total, soluble, and insoluble dietary fibers, total phenols, epicatechin, gallic and p-coumaric acids, and concentrations of Na, K, Mg, Ca, Fe, and Mn in whole persimmons, their pulps, and peels were significantly higher than in whole apples, pulps, and peels (P < 0.01-0.0025). Conversely, the contents of Cu and Zn were higher in apples than in persimmons. In persimmons and apples all of the above components were higher in their peels than in whole fruits and pulps. The relatively high contents of dietary fibers, total and major phenolics, main minerals, and trace elements make persimmon preferable for an antiatherosclerotic diet. 相似文献
894.
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
895.
Romero C Brenes M García P Garrido A 《Journal of agricultural and food chemistry》2002,50(13):3835-3839
There is increasing interest in olive polyphenols because of their biological properties as well as their contribution to the color, taste, and shelf life of olive products. However, some of these compounds remain unidentified. It has been shown that hydroxytyrosol 4-beta-D-glucoside (4-beta-D-glucosyl-3-hydroxyphenylethanol) coeluted with hydroxytyrosol [(3,4-dihydroxyphenyl)ethanol] under reversed phase conditions in the phenolic chromatograms of olive pulp, vegetation water, and pomace of olive oil processing. A method to separate this compound from hydroxytyrosol by HPLC has been developed. The concentration of this glucoside increased in olive pulp with maturation and could be the main phenolic compound in mature olives. In contrast, the presence of this compound was not detected in olive oil by using HPLC-MS. The compound must be considered both in table olives and olive oil processing because of its glucose and hydroxytyrosol contribution to these products. 相似文献
896.
The seed storage protein composition of one collection of cultivated einkorn wheat (Triticum monococcum L. ssp. monococcum) of Spanish origin has been analysed by SDS-PAGE and A-PAGE. Three allelic variants were detected for the Glu-A1m, whereas up to six alleles were detected for the Glu-A3m. For the gliadins, 7 and 14 alleles for the Gli-A1m and Gli-A2m were found between the evaluated accessions. Internal variability was detected in some of these materials, which could be
related to the landrace nature of them. Up to 48 different genotypes based on the origin and seed storage protein composition
have been identified. Further researches on these materials must be carried out for determining the variability degree in
morphological traits that could complement the evaluation for their safeguard. 相似文献
897.
Slobodan Miko Georg Koch Saša Mesić Martina Šparica Miko Marko Šparica Polona Vreča Tadej Dolenec 《Journal of Soils and Sediments》2007,7(5):303-312
Background, Aim and Scope
Most of the cathment areas supplying water and mineral matter to the Adriatic bays with healing mud/peloids are affected by various degrees of human impact, i.e. activity that is introducing various types of contaminants to environment. The bays represent shallow marine depositional environments where organic-rich sediments accumulate. Investigations for balneological characterization of several localities along the Croatian coast have shown that these organic-rich sediments may be classified as healing mud, i.e. peloids. Healing mud due to its balneologic features is in treatment of various diseases and in improvement of the overall health conditions and general well-being. Various components of mud, particularly trace elements, could be absorbed through dermal contact. Therefore, the study of the abundance of such potentially toxic elements as As, Pb, Hg, Cd, Se, Sb, Cu, Zn in marine sediments used as healing mud is necessary in order to know their mobility and to avoid possible intoxications. 相似文献898.
Gómez-Plaza E Gil-Muñoz R López-Roca JM Martínez A 《Journal of agricultural and food chemistry》2000,48(3):736-741
The purpose of this work was to determine the influence of vinification technique (maceration temperature and clarification method), storage temperature, and length of storage time on the phenolic compounds and color of young red wines. Multivariate analysis of variance and principal component analysis pointed to significant differences among all of the variables according to vinification technique and length of storage time. Storage temperature did not cause significant differences between some of the variables. The best color characteristics were obtained when low-temperature maceration wines were clarified with polyvinylpyrrolidone. Color quality also improved with lower storage temperature. 相似文献
899.
Robson Thiago Xavier de Sousa Gaspar Henrique Korndörfer Rogério Augusto Brem Soares Patrícia Rezende Fontoura 《Journal of plant nutrition》2015,38(9):1444-1455
Phosphate applications are still rare in sugarcane cultivation and can be done with phosphorus fertilizers of residual over. This study aims to evaluate the agronomic efficiency of phosphate fertilization before sugarcane planting and its effect on sugarcane yield. The study was carried out over three crop cycles at the Jalles Machado sugar-mill in Goianésia, GO, Brazil. The treatments consisted of five different phosphorus sources (soluble and insoluble) applied at a rate of 300 kg ha?1 phosphorus pentoxide (P2O5). The phosphorus fertilizers used were: triple superphosphate, mono-ammonium phosphate (MAP), Arad rock phosphate, Itafós rock phosphate, and magnesium term phosphate. The effects of these fertilizers were evaluated by plant height (ground to Top Visible Dewlap; TVD), leaf phosphorus content, agronomic efficiency, and sugarcane yield from cane-plants, first ratoon, and second ratoon. Magnesium term phosphate and triple superphosphate resulted in greater plant-cane height. Leaf phosphorus concentrations were highest with applications of MAP, magnesium term phosphate, and triple superphosphate. Phosphate applications did not affect sugarcane plant yield, but did increase ratoon yield. In general, the residual effect of insoluble phosphate increased over the years. The agronomic efficiency (AE) of phosphate was (in descending order): triple superphosphate (100%), term phosphate (89%), MAP (80%), Itafós rock phosphate (67%), and Arad rock phosphate (60%). 相似文献
900.
María López-Martín Marta Velasco-Molina Heike Knicker 《Journal of Soils and Sediments》2016,16(2):360-370