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991.
M. Szechyńska‐Hebda M. Hebda D. Mierzwiński P. Kuczyńska M. Mirek M. Wędzony A. van Lammeren S. Karpiński 《Plant pathology》2013,62(4):867-878
This study showed that several mechanisms of the basal resistance of winter triticale to Microdochium nivale are cultivar‐dependent and can be induced specifically during plant hardening. Experiments and microscopic observations were conducted on triticale cvs Hewo (able to develop resistance after cold treatment) and Magnat (susceptible to infection despite hardening). In cv. Hewo, cold hardening altered the physical and chemical properties of the leaf surface and prevented both adhesion of M. nivale hyphae to the leaves and direct penetration of the epidermis. Cold‐induced submicron‐ and micron‐scale roughness on the leaf epidermis resulted in superhydrophobicity, restricting fungal adhesion and growth, while the lower permeability and altered chemical composition of the host cell wall protected against tissue digestion by the fungus. The fungal strategy to access the nutrient resources of resistant hosts is the penetration of leaf tissues through stomata, followed by biotrophic intercellular growth of individual hyphae and the formation of haustoria‐like structures within mesophyll cells. In contrast, a destructive necrotrophic fungal lifestyle occurs in susceptible seedlings, despite cold hardening of the plants, with the host epidermis, mesophyll and vascular tissues being digested and becoming disorganized as a result of the low chemical and mechanical stability of the cell wall matrix. This work indicates that specific genetically encoded physical and mechanical properties of the cell wall and leaf tissues that depend on cold hardening are factors that can determine plant resistance against fungal diseases. 相似文献
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Polyurethane (PU) films containing different amounts of fly ash particles (FAPs) were prepared by simple solution casting method. The morphological, thermal, and mechanical properties of the composite films were investigated by several characterization methods. Results show that sufficient amounts (up to 40 wt%) of FAPs can be incorporated throughout the film. The presence of FAPs within PU film not only acts as filler to increase the mechanical strength of the film but also increases its volatile organic compounds (VOCs) adsorption capacity. The VOCs adsorption capacity of FAPs/PU composite films were investigated on three different compounds (chloroform, toluene, and benzene). It showed consistent trend in the order of toluene > benzene > chloroform for all the samples. The VOCs adsorption capacity of PU film was found to be increased by two fold when 20 wt% of FA was incorporated through it. The present results suggest the potential use of FAPs as filler materials for PU films with improved VOCs adsorption from outdoor and indoor air. 相似文献
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Barbara Lorkowska-Zawicka Kamil Kamiński Justyna Ciejka Krzysztof Szczubia?ka Magdalena Bia?as Krzysztof Okoń Dariusz Adamek Maria Nowakowska Jacek Jawień Rafa? Olszanecki Ryszard Korbut 《Marine drugs》2014,12(7):3953-3969
This study was performed to evaluate the ability of N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC), the cationically modified chitosan, to form biologically inactive complexes with unfractionated heparin and thereby blocking its anticoagulant activity. Experiments were carried out in rats in vivo and in vitro using the activated partial thromboplastin time (APTT) and prothrombin time (PT) tests for evaluation of heparin anticoagulant activity. For the first time we have found that HTCC effectively neutralizes anticoagulant action of heparin in rat blood in vitro as well as in rats in vivo. The effect of HTCC on suppression of heparin activity is dose-dependent and its efficacy can be comparable to that of protamine-the only agent used in clinic for heparin neutralization. HTCC administered i.v. alone had no direct effect on any of the coagulation tests used. The potential adverse effects of HTCC were further explored using rat experimental model of acute toxicity. When administered i.p. at high doses (250 and 500 mg/kg body weight), HTCC induced some significant dose-dependent structural abnormalities in the liver. However, when HTCC was administered at low doses, comparable to those used for neutralization of anticoagulant effect of heparin, no histopathological abnormalities in liver were observed. 相似文献
995.
Jae-hong Choi Mi-hyeon Kim Joon-soo Park Jeong-min Jeon Dae-ok Kim A. D. Towns 《Fibers and Polymers》2007,8(1):37-42
In Part 1 of this study, the dyeability, color shade, wash, light fastness and compatibility of homogeneous disperse dyes
on PLA fabric and PET fabric were reported. The present paper (Part 2) focuses on the application of commercial disperse dyes
to PLA fabric. Specific areas of investigation are the coloration properties of dyes originally intended for the production
of high lightfastness polyester fabrics or for application to cellulose diacetate. The compatibility of the eight members
of the dye set was investigated. In terms of lightfastness, the ratings were higher than that of conventional disperse dyes.
In addition, the use of dye combinations to achieve synergistic uptake on PLA was explored leading to the pronounced synergism
with a mixture of CI Disperse Blue 374 and 284. 相似文献
996.
Summary Available information has been reviewed on tuber resistance toP. infestans, its inheritance and breeding procedures used to obtain potato cultivars superior in this character.
P. infestans is worldwide the most destructive potato pathogen. Tuber resistance is an essential component of potato resistance as this
pathogen is often responsible for tuber rot in storage, and infected tubers of susceptible cultivars provide an important
way for its overwintering.
In Europe many cultivars and advanced breeders selections have been obtained with tuber resistance toP. infestans, but in the last decades no progress is noted in the mean level of this resistance in cultivars. The expression of tuber
resistance depends to a large extent on testing conditions and therefore it can be difficult to evaluate. Consequently making
progress in breeding is not easy, and also cultivar assessment data from various countries sometimes differ considerably.
It is concluded from published data that it should be easier to make progress in breeding potato cultivars with resistant
tubers if more attention is paid to combining the various types of resistance which are already known, and if the genetic
determination of durable resistance toP. infestans is better understood.
Professor Dr. K.M. Świeżyński passed away on 27th July 2000 相似文献
997.
Warabieda Michał Mikiciński Artur Oleszczak Marcin Puławska Joanna 《European journal of plant pathology / European Foundation for Plant Pathology》2021,161(3):543-552
European Journal of Plant Pathology - In April 2019, hydroponically cultivated cucumber plants with characteristic symptoms of crazy root disease were found in two different commercial production... 相似文献
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