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161.
162.
Journal of Plant Diseases and Protection - The study assessed the genetic variability among Macrophomina phaseolina (Tassi) Goid. isolates originating from six different countries (Turkey,...  相似文献   
163.
Journal of Plant Diseases and Protection - Prior to the first occurrence of chestnut blight in 1976, leaf spot caused by Cylindrosporium castaneae was one of the most important diseases of European...  相似文献   
164.
Landscape Ecology - In the original publication of the article, the third author name has been misspelt. The correct name is given in this Correction. The original version of this article was revised.  相似文献   
165.
Landscape Ecology - Landscape structure can affect seed dispersal, but the spatial scale at which such effect is maximized (scale of effect, SoE) is unknown. We assessed patterns and predictors of...  相似文献   
166.
为了实现精准喷雾,设计并制作了一套基于51单片机的精准喷雾自动/手动两种模式切换的控制装置。在自动模式下,单片机根据现场信号输入模块提供的作物病虫害情况分别打开或关闭对应的电磁阀;手动模式下,由面板手动开关分别控制各个电磁阀打开或关闭。经田间试验测定,该喷雾控制装置能够在自动或手动模式下实现精准喷雾作业控制。  相似文献   
167.
Defining the validity of a biochemical index of soil quality   总被引:2,自引:0,他引:2  
 The native soils of Galicia (NW Spain) exhibit a biochemical equilibrium such that total soil N is a function of five biochemical and microbiological parameters: microbial biomass C, mineralized N, phosphomonoesterase, β-glucosidase and urease activities. To investigate whether the ratio of the total N calculated from biochemical soil properties (Nc) and the total N as measured by the Kjeldahl method (Nk; Nc/Nk) can be used as an index of soil quality, we determined these variables and consequently the ratio in three kinds of disturbed soils: an artificially Cu-contaminated soil, two lignite mine soils, and a number of arable soils. In none of the studied soils did the individual biochemical parameters respond consistently to the factors influencing soil quality, but in all cases soil degradation was reflected by the Nc/Nk value, which differed more or less markedly from 100%. Nc/Nk can therefore be used for the rapid evaluation of soil degradation, since it distinguishes among biochemically balanced soils, soils in a transient state of high microbiological and biochemical activity and degraded soils. It can also serve as a reliable basis for the rapid calculation of the "ecological dose" (ED50) of soil pollutants. The use of Nc/Nk as an objective index of the biochemical quality of soils is recommended. Received: 20 December 1998  相似文献   
168.
In this paper we present surface dynamic properties (interfacial tension and surface dilational properties) of a whey protein isolate with a high content of beta-lactoglobulin (WPI) adsorbed on the oil-water interface as a function of adsorption time. The experiments were performed at constant temperature (20 degrees C), pH (5), and ionic strength (0.05 M). The surface rheological parameters and the interfacial tension were measured as a function of WPI concentration (ranging from 1 x 10(-)(1) to 1 x 10(-)(5)% w/w) and different processing factors (effect of convection and heat treatment). We found that the interfacial pressure, pi, and surface dilational modulus, E, increase and the phase angle, phi, decreases with time, theta, which should be associated with WPI adsorption. These phenomena have been related to diffusion of the protein toward the interface (at short adsorption time) and to the protein unfolding and/or protein-protein interactions (at long-term adsorption) as a function of protein concentration in solution and processing conditions.  相似文献   
169.
Supercritical fluid carbon dioxide extraction (SFE) has been evaluated for the extraction of 17 organohalogen and organophosphate pesticides in gazpacho (a table-ready food composite containing crude vegetables, white bread, vegetable oil, water, and other minor components) using anhydrous magnesium sulfate as drying agent. The effects of different parameters, such as fat content in gazpacho composites, magnesium sulfate/gazpacho ratio, supercritical fluid volume, pressure, temperature, and static modifier additions, on SFE recoveries from spiked gazpacho samples have been studied. Analyses were performed by gas chromatography (GC) with flame photometric (FPD), electron capture (ECD), and mass spectrometry (MSD) detectors. In most experiments, recoveries obtained for the nonpolar organohalogen pesticides were lower than those obtained for the most polar organophosphate pesticides, but overall pesticide recoveries determined by using the optimal SFE conditions indicate that SFE could be used to determine pesticide residue levels in gazpacho.  相似文献   
170.
The effect of 1-methylcyclopropene (1-MCP) at three different doses (0.25, 0.50, and 0.75 microL L(-1)) on the ripening processes of a climacteric, cv. Santa Rosa, and a suppressed climacteric type, cv. Golden Japan, plum was studied. For both cultivars, positive effects were observed in terms of inhibition of ethylene production and delays of the physical, chemical, and biochemical changes associated with ripening. 1-MCP-treated plums were firmer with lower weight loss, reduced degrees Brix/titratable acidity ratios, and lower color changes during cold storage and subsequent shelf life at 20 degrees C than controls. For most factors, the effectiveness of 1-MCP was dose-dependent in Santa Rosa but dose-independent for Golden Japan.  相似文献   
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