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131.
Julia A. Richter Jan H. Behr Alexander Erban Joachim Kopka Christian Zrb 《Plant, cell & environment》2019,42(1):295-309
Salt‐affected farmlands are increasingly burdened by chlorides, carbonates, and sulfates of sodium, calcium, and magnesium. Intriguingly, the underlying physiological processes are studied almost always under NaCl stress. Two faba bean cultivars were subjected to low‐ and high‐salt treatments of NaCl, Na2SO4, and KCl. Assimilation rate and leaf water vapor conductance were reduced to approximately 25–30% without biomass reduction after 7 days salt stress, but this did not cause severe carbon shortage. The equimolar treatments of Na+, K+, and Cl? showed comparable accumulation patterns in leaves and roots, except for SO42? which did not accumulate. To gain a detailed understanding of the effects caused by the tested ion combinations, we performed nontargeted gas chromatography–mass spectrometry‐based metabolite profiling. Metabolic responses to various salts were in part highly linearly correlated, but only a few metabolite responses were common to all salts and in both cultivars. At high salt concentrations, only myo‐inositol, allantoin, and glycerophosphoglycerol were highly significantly increased in roots under all tested conditions. We discovered several metabolic responses that were preferentially associated with the presence of Na+, K+, or Cl?. For example, increases of leaf proline and decreases of leaf fumaric acid and malic acid were apparently associated with Cl? accumulation. 相似文献
132.
Plants defend their leaves using multiple defense traits that change functions with leaf age. We examined the effects of leaf age on the development of multiple defense traits in two related Mallotus (Euphorbiaceae) species: young plants of the fast‐growing Mallotus japonicus (Spreng.) Müll. Arg. and the slow‐growing Mallotus philippensis (Lam.) Müll. Arg. Sequential leaves of the two species were measured for their leaf area, leaf mass/area, densities of trichomes and pellucid dots, extrafloral nectar volume, and the numbers of extrafloral nectaries and pearl bodies. Mallotus japonicus shifted its defense tactics from direct defense using trichomes and pellucid dots in young leaves to biotic defense using extrafloral nectar and pearl bodies in middle‐aged leaves. In contrast, M. philippensis used direct, chemical defense throughout all leaf ages, together with the shift from indirect, biotic defense using extrafloral nectar in young leaves to direct, physical defense using leaf toughness in middle‐aged leaves. These results strongly suggest that, in relation to life history, plants can alter optimal combinations of multiple defense traits with leaf age. 相似文献
133.
山东半岛南部产卵场鳀鱼的产卵生态Ⅰ.鳀鱼鱼卵和仔稚幼鱼的数量与分布特征 总被引:6,自引:1,他引:5
2000-2004年5-7月,"北斗"号生物资源调查船对山东半岛南部产卵场进行了11个航次多学科的综合调查,鳀鱼鱼卵和仔稚幼鱼的数量与分布及其与环境因氐墓系为重点调查内容.调查结果表明:1)山东半岛南部产卵场5月中、下旬鳀鱼才进入产卵初期;6月上旬产卵个体逐渐增多,即将进入产卵盛期;6月中、下旬进入产卵盛期; 2)山东半岛南部产卵场中,35°N断面及其邻近海区的鳀鱼鱼卵密集分布区相当稳定,这一带海域基本上每年都有鱼卵的密集分布中心形成;北部海域的密集分布区的分布范围和分布位置变化比较大,但是,密集分布区一旦形成,鱼卵的平均密度相当可观;西南部沿岸一带海域的鱼卵数量很少.鳀鱼鱼卵的分布与海流、潮汐以及水温分布等物理海洋学要素的关系密切,南、北两个鱼卵密集分布区正是潮锋所在的位置,锋区的辐聚和卷夹作用,使鳀鱼鱼卵聚集成密集的斑块,从而形成了鱼卵的密集分布中心; 3)鳀鱼鱼卵在水体中的空间分布主要集中在上混合层,温跃层中的数量次之,下混合层的数量最少;统计学检验, 上混合层、温跃层和下混合层之间的鱼卵数量差异显著; 4)鳀鱼仔稚幼鱼的数量明显少于鱼卵,水平分布特征与鱼卵也有明显的差异. 相似文献
134.
S. Kim C.-G. Kim J. Oh B.-J. Kim † H.-S. Seo W.-S. Kim Y.-H. Lee ‡ 《Journal of fish biology》2008,72(5):1202-1214
An analysis of the 524 nucleotide long segment in the 16SrDNA mitochondrial gene of Maurolicus japonicus revealed that there are two major haplotypes (E and H) and two minor haplotypes (I and J), which comprise 63·6, 27·2, 4·6 and 4·6% of the population, respectively. The nucleotide sequence of the major haplotype E is identical to that of the most common haplotype in Maurolicus walvisensis (63·6% of the population). The other haplotypes of M. japonicus are almost identical to that of the haplotype E with only a single (haplotypes I and J) or three nucleotide differences (haplotype H). Phylogenetic trees of all the 16SrDNA haplotypes found thus far in the Maurolicus taxa show that the relationships among the haplotypes of M. japonicus and M. walvisensis are indistinguishable but that they are clearly distinctive from those of Maurolicus muelleri . Examination of the morphometric characteristics of specimens reveals similarities among the individuals of different haplotypes of M. japonicus and also between M. japonicus and M. walvisensis in almost all characteristics. The results suggest that despite the current ocean-wide allopatric distribution between M. japonicus and M. walvisensis , the two taxa are conspecific as M. japonicus . 相似文献
135.
136.
A new lindenane sesquiterpene glucoside named yinxiancaoside A (1), a new, rare bidesmosidic megastigmane sesquiterpene glucoside named yinxiancaoside B (5), and three known sesquiterpene glucosides, chloranoside A (2), pisumionoside (3), and sarcaglaboside A (4), were isolated from the whole plant of Chloranthus japonicus Sieb. The structures of the new compounds were established by an extensive study of their spectral data, especially 1D- and 2D-NMR. The cytotoxic activity of the isolated compounds against human hepatoma (Hepg-2), human ovarian carcinoma (OV420), and human breast cancer (MCF-7) cells was investigated. 相似文献
137.
Dae Sik Jang Jong Min Kim Junghyun Kim Jeong Lim Yoo Young Sook Kim Jin Sook Kim 《化学与生物多样性》2008,5(12):2718-2723
An anthraquinone, emodin ( 1 ), and five flavonoids, kaempferol‐3‐O‐β‐D ‐glucoside ( 2 ), quercetin ( 3 ), quercitrin ( 4 ), isoquercitrin ( 5 ), and (+)‐catechin ( 6 ), were isolated from an AcOEt‐soluble extract of the fruits of Rumex japonicus. Their structures were determined by spectroscopic data interpretation. All the isolates were evaluated for their potential to inhibit AGEs (advanced glycation end products) formation and AGEs cross‐linking, and to break already formed AGEs cross‐links. 相似文献
138.
本文构建了海鲈(Lateolabrax japonicus)头肾全长eDNA文库.PCR方法扩增得到海鲈的核糖体蛋白L8基因,全长848bp,编码257个氨基酸,含有L2及L2-C两个保守区.进化分析结果表明,以L8为参照的进化鉴定结果同经典的分子生物学标准18s鉴定结果十分相似,因此核糖体蛋白L8基因L8可以作为鉴定物种进化程度的新标准. 相似文献
139.
In eastern Hokkaidô, Japan, the native crayfish Cambaroides japonicus de Haan has been declining rapidly while the exotic crayfish Pacifastacus leniusculus Dana has been expanding its range. We speculated that the observed displacement of Cambaroides by Pacifastacus is partly due to an interference interaction for shelter between the two species. We studied the impacts of Pacifastacus on Cambaroides by testing experimentally whether intensity of interference, the outcome of dominance order and shelter occupancy differed between single- and mixed-species combinations of the two species. Pacifastacus showed less defensive behaviours towards Cambaroides than to conspecifics. In contrast, Cambaroides exhibited more defensive behaviours towards Pacifastacus than to conspecifics. Pairwise comparison of agonistic behaviours in mixed species groups revealed that Pacifastacus exhibiting frequently more aggressive attacks while Camaboides showing more defensive behaviours to their respective counterparts. Dominance in aggressive encounter generally dictated shelter occupancy in mixed-species and Pacifastacus pairs but not in Cambaroides pairs. Because shelter utilization, when these are not limited in supply, was much more frequent in Cambaroides than Pacifastacus, Cambaroides suffered interference from both conspecifics and heterospecifics when they competed for a single shelter. Pacifastacus, however, did not show any change in shelter occupancy in the presence or absence of conspecics or heterospecifics. Inferiority in aggressive interactions and shelter occupancy can therefore be a critical disadvantage for Cambaroides if shelters are limited in natural situations. 相似文献
140.
Hiroshi Fukuda 《Molluscan research.》2017,37(4):268-281
Based on the examination of old literature, the names of two species of Batillus Schumacher, 1817, a subgenus of Turbo Linnaeus, 1758, are revised. Turbo cornutus [Lightfoot], 1786 should be restricted to the species endemic to southern China and Taiwan. Turbo chinensis Ozawa & Tomida, 1995 is the junior synonym of T. cornutus. The species of Japan and Korea has long been misidentified with T. cornutus. Turbo japonicus Reeve, 1848 has been used for two very different species: one from Mauritius and another from Japan, with the species from Mauritius being valid, and a member of the subgenus Marmarostoma Swainson, 1840, while the Japanese/Korean species, lacking an available name, is provided with a new replacement name, T. sazae nom. nov.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:7E99BA4B-CEB5-4510-BC5E-7852232926B8 相似文献