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Natural history of Arabidopsis thaliana and oomycete symbioses 总被引:1,自引:1,他引:0
Eric B. Holub 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(1):91-109
Molecular ecology of plant–microbe interactions has immediate significance for filling a gap in knowledge between the laboratory
discipline of molecular biology and the largely theoretical discipline of evolutionary ecology. Somewhere in between lies
conservation biology, aimed at protection of habitats and the diversity of species housed within them. A seemingly insignificant
wildflower called Arabidopsis thaliana has an important contribution to make in this endeavour. It has already transformed botanical research with deepening understanding
of molecular processes within the species and across the Plant Kingdom; and has begun to revolutionize plant breeding by providing
an invaluable catalogue of gene sequences that can be used to design the most precise molecular markers attainable for marker-assisted
selection of valued traits. This review describes how A. thaliana and two of its natural biotrophic parasites could be seminal as a model for exploring the biogeography and molecular ecology
of plant–microbe interactions, and specifically, for testing hypotheses proposed from the geographic mosaic theory of co-evolution. 相似文献
995.
Atlantic salmon fed diets devoid of fishmeal but added 0.5 g kg?1 fish protein concentrate (FPC) showed reduced growth and lipid deposition without affecting protein accretion as compared to fish fed a fishmeal‐based control diet. The aim of the current study was to assess whether higher inclusion of FPC improved the growth and lipid deposition of Atlantic salmon (initial body weight 380 g) fed high plant protein diets. Quadruplicate groups of fish were fed diets containing 200 g kg?1 fishmeal of which was replaced with FPC (150, 112, 75, 38 and 0 g kg?1) for a period of 79 days. The rest of the diet protein was a mixture of plant proteins. The lipid source used was fish oil. A fishmeal‐based diet was included as a positive control for growth performance. None of the test diets differed from the positive control‐fed fish in voluntary feed intake, growth performance or nutrient accretion. Thus, the test diets were found appropriate to assess the effect of FPC inclusion. Replacement of fishmeal with increasing concentration of FPC did not affect voluntary feed intake (P = 0.56), but growth performance decreased (P = 0.02) resulting in an increased feed conversion ratio (P = 0.003). Viscerosomatic index decreased as diet FPC inclusion increased (P = 0.012) without affecting the dress out weight (P = 0.08). Thus, the apparently improved growth in fish fed the diets with the low FPC inclusion was because of a higher visceral mass. Possible reasons for the reduced visceral mass following addition of FPC to high plant protein diets are discussed. 相似文献
996.
以粘虫为供试昆虫,测定了天然分布于甘肃省天祝高寒草原的醉马草、异叶青兰、臭蒿、黄花马先蒿、山莨菪、披针叶黄华、乳白香青、节裂角茴香、密花香薷、锐果鸢尾、迷果芹、风毛菊、星状风毛菊、毛果婆婆纳、麻花艽、珠芽蓼等16种植物丙酮提取物的杀虫活性.结果表明:节裂角茴香、臭蒿对粘虫的拒食活性比较明显,处理后48 h对粘虫的拒食活率为72.1%、86.9%;披针叶黄华、迷果芹在处理后72 h对粘虫的触杀活性为30.0%和23.3%;醉马草在处理后48 h对粘虫的胃毒活性为16.7%.其他植物对供试粘虫杀虫活性较弱. 相似文献
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Highly preferred orientation copper coatings show excellent functions. Many factors affect copper coatings’ crystal preferred orientation, and additives are one of the factors. Copper coatings were prepared at 0.040 A/cm 2 and 0.150 A/cm 2 by constant current, respectively. The electrolytes were acid CuSO4 solution with additives MPS (3-mercapto propane sodium sulfonate) or SPS(poly-2-sulfur-2-propane sodium sulfonate), and their combinations with PEG (polyethylene glycol) and Cl -. X-ray diffraction shows that (220) lattice plane fully preferred orientation is obtained at the higher current density 0.150 A/cm 2 with the combination of MPS+Cl - or SPS+Cl -. But different preferred orientations are obtained with only MPS or SPS, or other combinations, such as MPS+PEG, MPS+PEG+Cl -, SPS+PEG, SPS+PEG+Cl -. Using different combinations of additives is an effective method to obtain highly preferred orientation lattice planes earlier in the process of electrodeposition. 相似文献
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The structure and principle of double-channel elliptical crystal spectrometer are presented.The whole process of manufacturing dispersive element with natural muscovite is specified.The instrument was applied to diagnose plasma produced by laser on "XG-II" facility and the spectrum of flat Au was obtained.In order to analyze the reason of unsatisfactory pattern in which spectral lines interveined each other,X-ray diffraction experiment and observating surface of muscovite were conducted.The experimental results show that using such natural muscovite as dispersive element is the real reason for interlaced spectrum. 相似文献