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941.
Signalling requirements for Erwinia amylovora‐induced disease resistance,callose deposition and cell growth in the non‐host Arabidopsis thaliana 下载免费PDF全文
Safae Hamdoun Min Gao Manroop Gill Ashley Kwon John L. Norelli Hua Lu 《Molecular Plant Pathology》2018,19(5):1090-1103
Erwinia amylovora is the causal agent of the fire blight disease in some plants of the Rosaceae family. The non‐host plant Arabidopsis serves as a powerful system for the dissection of mechanisms of resistance to E. amylovora. Although not yet known to mount gene‐for‐gene resistance to E. amylovora, we found that Arabidopsis activated strong defence signalling mediated by salicylic acid (SA), with kinetics and amplitude similar to that induced by the recognition of the bacterial effector avrRpm1 by the resistance protein RPM1. Genetic analysis further revealed that SA signalling, but not signalling mediated by ethylene (ET) and jasmonic acid (JA), is required for E. amylovora resistance. Erwinia amylovora induces massive callose deposition on infected leaves, which is independent of SA, ET and JA signalling and is necessary for E. amylovora resistance in Arabidopsis. We also observed tumour‐like growths on E. amylovora‐infected Arabidopsis leaves, which contain enlarged mesophyll cells with increased DNA content and are probably a result of endoreplication. The formation of such growths is largely independent of SA signalling and some E. amylovora effectors. Together, our data reveal signalling requirements for E. amylovora‐induced disease resistance, callose deposition and cell fate change in the non‐host plant Arabidopsis. Knowledge from this study could facilitate a better understanding of the mechanisms of host defence against E. amylovora and eventually improve host resistance to the pathogen. 相似文献
942.
Deok Ho Kwon In-Hong Jeong Sung Jun Hong Myung-Pyo Jung Ki-Su Kim Si Woo Lee Si Hyeock Lee 《Journal of Asia》2018,21(1):293-300
The small brown planthopper (SBPH, Laodelphax striatellus Fallén) is an important pest that causes severe yield losses in rice by transmitting viral plant diseases. For the proper management of this pest, therefore, it is necessary to understand its temporal and spatial dynamics by establishing a periodical monitoring system. A dataset, including the number of SBPHs by location, collection method [aerial collection net (AeCN) or light trap (LT)] and period (May–Aug.) for five years (2011–2015) was provided by the Rural Developmental Administration, and missing values were imputed using multiple imputation methods. Of the 15,848 individuals collected, approximately 47% and 52.9% were collected using the AeCN and LT methods, respectively. Large numbers of SBPHs were generally collected from western coastal regions using AeCNs but not LTs. A high incidence of migratory SBPHs was observed during Julian days 144–166 using the AeCN method, with slightly different migration periods in each year. Generally, the migratory SBPHs made up 39.4% of the total populations of SBPHs during those periods. According to clustering analysis, the migratory region was located along the western coastal regions. Putative migration paths were estimated by trajectory cluster analyses using meteorological data. Interestingly, an L-shaped trajectory path emerged as a potentially important route for migratory SBPHs, passing through major wheat cultivation areas in Henan, Anhui, Jiangsu, and Zhejiang provinces in China, where high densities of SBPHs occur from late May to early June. These results would provide valuable information to predict the incidence period of migratory SBPHs and establish a proactive management system against SBPH, including the basis for the detection of hazardous factors and decisions regarding appropriate pesticide treatment periods. 相似文献
943.
Adjusting the Anisotropy of 1D Sb2Se3 Nanostructures for Highly Efficient Photoelectrochemical Water Splitting 下载免费PDF全文
Wooseok Yang Jihoon Ahn Yunjung Oh Jeiwan Tan Hyungsoo Lee Jaemin Park Hyeok‐Chan Kwon Juran Kim William Jo Joosun Kim Jooho Moon 《Liver Transplantation》2018,8(14)
Sb2Se3 has recently spurred great interest as a promising light‐absorbing material for solar energy conversion. Sb2Se3 consists of 1D covalently linked nanoribbons stacked via van der Waals forces and its properties strongly depend on the crystallographic orientation. However, strategies for adjusting the anisotropy of 1D Sb2Se3 nanostructures are rarely investigated. Here, a novel approach is presented to fabricate 1D Sb2Se3 nanostructure arrays with different aspect ratios on conductive substrates by simply spin‐coating Sb‐Se solutions with different molar ratios of thioglycolic acid and ethanolamine. A relatively small proportion of thioglycolic acid induces the growth of short Sb2Se3 nanorod arrays with preferred orientation, leading to fast carrier transport and enhanced photocurrent. After the deposition of TiO2 and Pt, an appropriately oriented Sb2Se3 nanostructure array exhibits a significantly enhanced photoelectrochemical performance; the photocurrent reaches 12.5 mA cm?2 at 0 V versus reversible hydrogen electrode under air mass 1.5 global illumination. 相似文献
944.
Improving the Performance and Stability of Inverted Planar Flexible Perovskite Solar Cells Employing a Novel NDI‐Based Polymer as the Electron Transport Layer 下载免费PDF全文
Hong Il Kim Myeong‐Jong Kim Kyoungwon Choi Chaesung Lim Yun‐Hi Kim Soon‐Ki Kwon Taiho Park 《Liver Transplantation》2018,8(16)
A new naphthalene diimide (NDI)‐based polymer with strong electron withdrawing dicyanothiophene (P(NDI2DT‐TTCN)) is developed as the electron transport layer (ETL) in place of the fullerene‐based ETL in inverted perovskite solar cells (Pero‐SCs). A combination of characterization techniques, including atomic force microscopy, scanning electron microscopy, grazing‐incidence wide‐angle X‐ray scattering, near‐edge X‐ray absorption fine‐structure spectroscopy, space‐charge‐limited current, electrochemical impedance spectroscopy, photoluminescence (PL), and time‐resolved PL decay, is used to demonstrate the interface phenomena between perovskite and P(NDI2DT‐TTCN) or [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM). It is found that P(NDI2DT‐TTCN) not only improves the electron extraction ability but also prevents ambient condition interference by forming a hydrophobic ETL surface. In addition, P(NDI2DT‐TTCN) has excellent mechanical stability compared to PCBM in flexible Pero‐SCs. With these improved functionalities, the performance of devices based on P(NDI2DT‐TTCN) significantly outperform those based on PCBM from 14.3 to 17.0%, which is the highest photovoltaic performance with negligible hysteresis in the field of polymeric ETLs. 相似文献
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948.
Sang Mi An Jung Hye Hwang Seulgi Kwon Go Eun Yu Da Hye Park Deok Gyeong Kang 《Animal biotechnology》2018,29(4):301-308
Litter size is among the most important traits in swine breeding. However, information on the genetics of litter size in pigs is lacking. In this study, we identified single nucleotide polymorphisms (SNPs) in the insulin-like growth factor binding protein 2 and 3 (IGFBP2 and IGFBP3) genes in Berkshire pigs and analyzed their association with litter size traits. The IGFBP2 SNP was located on chromosome 15 intron 2 (455, A?>?T) and the IGFBP3 SNP was on chromosome 18 intron 2 (53, A?>?G). The AT type of IGFBP2 and the GG type of IGFBP3 had the highest values for all litter size traits including total number born (TNB), number of pigs born alive, and breeding value according to TNB. Homozygous GG pigs expressed higher levels of IGFBP3 mRNA in the endometrium than pigs of other genotypes, and a positive correlation was observed between litter size traits and IGFBP3 but not IGFBP2 expression level. These results suggest that SNPs in the IGFBP2 and the IGFBP3 gene are useful biomarkers for increasing the reproductive productivity of Berkshire pigs. 相似文献
949.
950.
Kwang-Hee Son Young-Kook Kim Hyun-Woo Lee Woo-Sang Lee Sung-Uk Kim Tae-Sook Jeong Byoung-Mog Kwon Song-Hae Bok 《Biotechnology letters》1996,18(11):1297-1300
Summary Fermentation optimization for the fungus Aspergillus fumigatus F93 was performed to amplify the most promising biological activity. Twelve active variables were analysed and optimized by the Plackett-Burman design, consisting of 16 experiments. Farnesyl protein transferase inhibitory activity showed the best response for the design, and selected parameters were confirmed by separate experiments in the optimized fermentation condition. 相似文献