Pseudozyma spp. are yeast-like fungi, classified in the Ustilaginales, which are mostly epiphytic or saprophytic and are not pathogenic to plants. Several Pseudozyma species have been reported to exhibit biological activity against powdery mildews. However, previous studies have reported that Pseudozyma aphidis, which can colonize plant surfaces, is not associated with the collapse of powdery mildew colonies. In this report, we describe a novel P. aphidis strain and study its interactions with its plant host and the plant pathogen Botrytis cinerea. This isolate was found to secrete extracellular metabolites that inhibit various fungal pathogens in vitro and significantly reduce B. cinerea infection in vivo. Moreover, P. aphidis sensitized Arabidopsis (Arabidopsis thaliana) plants' defense machinery via local and systemic induction of PATHOGENESIS-RELATED1 (PR1) and PLANT DEFENSIN1.2 (PDF1.2) expression. P. aphidis also reduced B. cinerea infection, locally and systemically, in Arabidopsis mutants impaired in jasmonic acid (JA) or salicylic acid (SA) signaling. Thus, in addition to direct inhibition, P. aphidis may inhibit B. cinerea infection via induced resistance in a manner independent of SA, JA, and Nonexpressor of PR1 (NPR1). P. aphidis primed the plant defense machinery and induced stronger activation of PDF1.2 after B. cinerea infection. Finally, P. aphidis fully or partially reconstituted PR1 and PDF1.2 expression in npr1-1 mutant and in plants with the SA hydroxylase NahG transgene, but not in a jasmonate resistant1-1 mutant, after B. cinerea infection, suggesting that P. aphidis can bypass the SA/NPR1, but not JA, pathway to activate PR genes. Thus, either partial gene activation is sufficient to induce resistance, or the resistance is not directed solely through PR1 and PDF1.2 but probably through other pathogen-resistance genes or pathways as well.

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Articles you may be interested inEffective lifetime of electrons trapped in the oxide of a metal-oxide-semiconductor structure Appl. Phys. Lett. 75, 522 (1999); 10.1063/1.124435 Depth profile of trapped charges in oxide layer of 6HSiC metal-oxide-semiconductor structures Determination of trapped charge distributions in the dielectric of a metaloxidesemiconductor structure J. Appl. Phys. 57, 5359 (1985); 10.1063/1.334856Capture and release of electrons on Na+related trapping sites in the SiO2 layer of metaloxide semiconductor structures at temperatures between 77 and 296°K This paper discusses electron injected induced trapping-detrapping behavior of nitrided gate insulators and its consistency with the dynamic balance model which characterizes standard silicon dioxide insulators. The experimental results show that the dynamic trapping model is also applicable for the novel nitrided insulators; trapping-detrapping characteristics are field dependent, the magnitude of the trapped negative charge is reduced when the electric field is increased, trappingdetrapping reversibility is evident, steady state trapping level is determined by the insulator field, and the trapping and detrapping transients are dominated by ,the density of the injected electrons. The occupation probability function is determined to be almost identical for both insulator types. The main difference between nitrided insulators and control oxides is lower trapping cross sections for nitrided insulators, and lower concentration of generated traps leading to improved immunity to degradation during charge injection. The novel dielectric layer is of potential use for the fabrication of reliable ultrathin gate oxide films for standard complementary metal-oxide-semiconductor

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Silicon epitaxy and selective poly-epi growth (SPEG) were performed in a conventional epitaxy system at temperatures below 1000~ using a silane source in hydrogen ambient. Characterization methods included secondary ion mass spectrometry, transmission electron microscopy (TEM), scanning electron microscopy, and electrical measurements. Epitaxial silicon layers with good quality were obtained for both uniform and SPEG wafers at temperatures as low as 850~ A strong correlation between the electrical results and the interfacial oxygen concentrations was obtained. The electrical results degrade while the interfacial oxygen concentration increases as the bake and deposition temperatures are reduced. This is attributed to inefficient removal of the native oxide. Nevertheless, the presence of relatively small precipitates of silicon oxide seen by TEM may still permit growth of an epitaxial layer with good electrical quality. The epitaxial layer was found to be about 50% thicker than the poly layer deposited over the oxide. This is explained by the smaller sticking coefficient of silicon to oxide as compared to that of silicon to silicon. This difference in layer thickness results in the formation of facets at the transition region between poly and epi.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 152.14.136.77 Downloaded on 2015-03-11 to IP