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11.
CH Balachiranjeevi Naik S. Bhaskar V. Abhilash S. Akanksha B. C. Viraktamath M. S. Madhav A. S. Hariprasad G. S. Laha M. S. Prasad S. M. Balachandran C. N. Neeraja M. Satendra Kumar P. Senguttuvel K. B. Kemparaju V. P. Bhadana T. Ram G. Harika H. K. Mahadeva Swamy S. K. Hajira A. Yugander K. Pranathi M. Anila G. Rekha M. B. V. N. Kousik T. Dilip Kumar R. K. Swapnil Archana Giri R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2015,35(7):1-12
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H. W. Krause H.-J. Kreuzfeld U. Schmidt CH Dbler M. Michalik S. Taudien Ch. Fischer 《Chirality》1996,8(2):173-188
Substituted N-Cbz and N-Boc protected arylamino acrylic acids and esters have been prepared and used in asymmetric hydrogenations catalyzed by PROPRAPHOSRh. Stereoselectivities > 90% ee could be achieved, the rate of which is dependent on the position of the substituent in the aromatic ring. The N-Boc derivatives provide advantages compared with the N-Cbz analogues. The amino acid derivatives were fully characterized by 19F, 13C, and 1H NMR spectroscopy. © 1996 Wiley-Liss, Inc. 相似文献
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ON THE EARLY GROWTH RATE OF THE INDIVIDUAL FUNGUS HYPHA 总被引:1,自引:0,他引:1
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Acaricidal activity of Metarhizium anisopliae isolated from paddocks in the Mexican tropics against two populations of the cattle tick Rhipicephalus microplus 下载免费PDF全文
A. FERNÁNDEZ ‐SALAS M. A. ALONSO‐DÍAZ R. A. ALONSO‐MORALES R. LEZAMA‐GUTIÉRREZ J. C. RODRÍGUEZ‐RODRÍGUEZ J. A. CERVANTES‐CHÁVEZ 《Medical and veterinary entomology》2017,31(1):36-43
The acaricidal effects of 55 strains of Metarhizium anisopliae (Metschnikoff) Sorokin, 1883 (Hypocreales: Clavicipitaceae) isolated from paddocks of cattle farms were evaluated in two Rhipicephalus microplus (Canestrini 1887) (Ixodida: Ixodidae) populations, of which one was multi‐resistant and one was susceptible to chemical acaricides. Percentage mortality and reproductive efficiency indices in R. microplus were evaluated by adult immersion tests at a dose of 1 × 108 conidia/mL for each fungal strain. Some strains were selected to calculate lethal concentrations to kill 50% (LC50) and 99% (LC99) of engorged ticks. Strains MaV22, MaV26 and MaV55 induced 100% mortality in R. microplus on day 14. Strains MaV05, MaV09 and MaV22 caused mortality of >90% from day 12 onward in both tick populations. The most effective acaricidal fungal strain, MaV55, inhibited egg laying by 54.86 and 55.86% in acaricide‐resistant and ‐susceptible R. microplus populations, respectively. None of the fungal strains had statistically significant effects on larval hatching. In conclusion, nine strains of M. anisopliae demonstrated high acaricidal effects against R. microplus and reduced its egg laying. No differences in acaricidal effects were observed between the two populations of ticks tested. 相似文献
15.
F. ORANGE F. WESTALL J.-R. DISNAR D. PRIEUR N. BIENVENU M. LE ROMANCER CH. DÉFARGE 《Geobiology》2009,7(4):403-418
Hydrothermal activity was common on the early Earth and associated micro‐organisms would most likely have included thermophilic to hyperthermophilic species. 3.5–3.3 billion‐year‐old, hydrothermally influenced rocks contain silicified microbial mats and colonies that must have been bathed in warm to hot hydrothermal emanations. Could they represent thermophilic or hyperthermophilic micro‐organisms and if so, how were they preserved? We present the results of an experiment to silicify anaerobic, hyperthermophilic micro‐organisms from the Archaea Domain Pyrococcus abyssi and Methanocaldococcus jannaschii, that could have lived on the early Earth. The micro‐organisms were placed in a silica‐saturated medium for periods up to 1 year. Pyrococcus abyssi cells were fossilized but the M. jannaschii cells lysed naturally after the exponential growth phase, apart from a few cells and cell remains, and were not silicified although their extracellular polymeric substances were. In this first simulated fossilization of archaeal strains, our results suggest that differences between species have a strong influence on the potential for different micro‐organisms to be preserved by fossilization and that those found in the fossil record represent probably only a part of the original diversity. Our results have important consequences for biosignatures in hydrothermal or hydrothermally influenced deposits on Earth, as well as on early Mars, as environmental conditions were similar on the young terrestrial planets and traces of early Martian life may have been similarly preserved as silicified microfossils. 相似文献
16.
CH. H. HÄNISCH TEN GATE J. VAN NETTEN J. F. DORTLAND J. BRUINSMA 《Physiologia plantarum》1975,33(4):276-279
Effects of metabolic inhibitors and growth regulators on the course of abscission and on the activities of cell wall solubilizing enzymes were studied in pedicel explants of Begonia flower buds. Actinomycin D, chloramphenicol and 2,4-dinitrophenol slightly retarded abscission, whereas cycloheximide exerted a strong inhibition if applied until 10.5 h after explant excision. Indoleacetic acid retarded and ethylene promoted abscission and cell wall solubilization. However, the activities of cell wall solubilizing enzymes did not correspond with the course of abscission. No polygalacturonase and pectic acid and pectin transeliminases could be detected in the abscission zone during abscission, whereas a low pectin methylesterase activity did not change. Endo- and exocellulase activities did not increase until about 10 h after the onset of abscission, indicating that they are the result rather than the cause of abscission. 相似文献
17.
ALEXEY V. F. CH. BOBROV PETER K. ENDRESS ALEXANDER P. MELIKIAN MIKHAIL S. ROMANOV ALEXEY N. SOROKIN ALEJANDRO PALMAROLA BEJERANO 《Botanical journal of the Linnean Society. Linnean Society of London》2005,148(3):265-274
The indehiscent fruitlets of the apparently basalmost extant angiosperm, Amborella trichopoda, have a pericarp that is differentiated into five zones, a thin one‐cell‐layered skin (exocarp), a thick fleshy zone of 25–35 cell layers (outer mesocarp), a thick, large‐celled sclerenchymatous zone (unlignified) of 6–18 cell layers (middle mesocarp), a single cell layer with thin‐walled (silicified?) cells (inner mesocarp), and a 2–4‐cell‐layered, small‐celled sclerenchymatous zone (unlignified) derived from the inner epidermis (endocarp). The border between inner and outer mesocarp is not even but the inner mesocarp forms a network of ridges and pits; the ridges support the vascular bundles, which are situated in the outer mesocarp. In accordance with previous observations by Bailey & Swamy, no ethereal oil cells were observed in the pericarp; however, lysigenous cavities as mentioned by these authors are also lacking; they seem to be an artefact caused by re‐expanding dried fruits. The seed coat is not sclerified. The fruitlets of Amborella differ from externally similar fruits or fruitlets in other basal angiosperms, such as Austrobaileyales or Laurales, in their histology. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148 , 265–274. 相似文献
18.
竹叶眼子菜(Potamogeton malaianus)、微齿眼子菜(Potamogeton maackianus)、苦草(Vallisneria spiralis)、穗花狐尾藻(Myriophyllum spicatum)、黑藻(Hydrilla verticillata)是长江中下游湖泊主要的沉水植物。在栽培条件下,它们的无性繁殖速率(单位时间内新增个体数)大小顺序为黑藻>微齿眼子菜>竹叶眼子菜>苦草>穗花狐尾藻。同时采用抛掷实验的方法观察研究了这5种沉水植物及其无性繁殖体的存活和生根情况;完整植株存活率为黑藻>穗花狐尾藻>微齿眼子菜>竹叶眼子菜>苦草,无性繁殖体部分存活率为黑藻>苦草>穗花狐尾藻>微齿眼子菜>竹叶眼子菜。生根能力和其存活时间长短相关,而且生根能力与存活率大小基本一致。在实验中,只有穗花狐尾藻的断枝存活率和生根能力存在差异,故无性繁殖体生根能力为黑藻>苦草>微齿眼子菜>竹叶眼子菜>穗花狐尾藻。 相似文献
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