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Optical strain measurement system based on three-dimension digital image correlation (3D-DIC) has been employed for postgraduate experiment teaching in the advanced experiment mechanics, and several research-oriented experiments have been designed and developed. This paper presents a typical experiment. The tensile elastic modulus of aluminum cylindrical specimens with through-hole was measured and the hole-edge strain concentration was observed directly. Furthermore, the elastic modulus of aluminum specimens performed by the proposed 3D-DIC system was carefully compared with this obtained by strain gage. The agreement between the two measurements was good. The experimental results demonstrated that the optical technique used for the measurement of elastic modulus of various material specimens was simple yet effective, hence, the high accuracy of 3D-DIC system was verified. More importantly, the optical technique provided a new study routine for the strain and displacement measurement of the specimens that cannot be measured by conventional contact methods. This high-accuracy 3D-DIC system can accomplish the three-dimension displacement and strain field contactlessly and visually. It was used in postgraduate experiment teaching. The result showed that the experiment can further enhance the capacity for scientific research and innovation and broaden the horizon of the students. And it makes postgraduates deeply understand and master the knowledge of mechanics and advanced measurement methods in the field of mechanics. [ABSTRACT FROM AUTHOR]

The coding products of WRKY gene family plays important roles in plant growth and development as well as in various stress responses. They have been identified in various plants, but only few in common tobacco (Nicotiana tabacum L.). In this study, 164 putative WRKY proteins in the common tobacco genome were identified by using the conserved WRKY sequence (PF03106) from the Pfam database. Phylogenetic trees, functional domain analysis, chromosomal localization, subcellular localization and tissue expression patterns were analyzed with the bioinformatics softwares, including DNAMAN 5.0, Weblogo 3, MEGA 5.1, MG2C and MEME. First of all, phylogenetic trees divided all the candidate genes into three subfamilies: Ⅰ, Ⅱ and Ⅲ, respectively, and subfamily Ⅱ could be further divided into five subgroups: group Ⅱ-a, -b, -c, -d and -e. Secondly, the WRKY regions contained a highly conserved heptapeptide stretch WRKYGQK followed by a zinc-finger motif. Most of the NtWRKY genes contained 2-5 exons and a highly conserved gene structure. Thirdly, 154 out of 164 NtWRKY genes were distributed with different densities on 24 chromosomes, and each subfamily with different patterns and frequency. The largest number of NtWRKY genes was found on chromosome VI, and only one on chromosome X. Fourthly, the majority of NtWRKY members located in the nucleus, with 74 percent of subfamily Ⅲ in the extracellular matrix. Lastly, the members in the same subfamily had different spatial and temporal expression profiles, with 11 NtWRKY genes in roots, stems and leaves expressed at various levels. The expression of genes NtWRKY26, NtWRKY30 and NtWRKY32 can be induced by Phytophthora nicotianae. Our research thus provides valuable information for NtWRKY gene cloning and functional characterization in common tobacco.

In this paper, Shannong 87074-519, a derivative of wheat-decaploid Elytrigia elongata, was identified by inoculation assessment, cytological analysis, simple sequence repeat (SSR), molecular marker technique,and genomic in situ hybridization (GISH). The results are as follows: the chromosome number of Shannong87074-519 in root tip cells was 2n=44, 22 bivalents were observed in most PMC at MI, and the average chromosome configuration was 2n=44=21.82 II+0.36 I , and the chromosome configuration (2n=43=21 II +1 I) was observed in most PMC of F1 between Shannong87074-519 and C.S. at MI. Therefore, it was an alien disomic addition line with one pair chromosome of Elytrigia elongata. Then the St total genomic DNA was labeled as probe in GISH, the green-yellow hybridization signal was observed in two intact chromosomes, indicating that Shannong87074-519 was added by one pair chromosome of St genome. The SSR-PCR technique was employed in the primer filtration, and the molecular marker BARC165 was singled out from 170 primers, which could amplify the specific molecular marker BARC165(268) of Elytrigia elongata in Shannong87074-519. Subsequently, the specific segment in Elytrigia elongata was cloned and labeled as probe in GISH of root tip cells of Shannong87074-519, the light yellow hybridization signal was observed in both chromatin at interphase and chromosome at mitotic metaphase, thus the BARC165(268) could be applied as a specific molecular marker to detect alien chromatin of Elytrigia elongata in Shannong87074-519. Because of the good agronomic characteristics, high immunity to yellow rust, and dominant new yellow rust resistant gene located at the added chromosome St, assigned as YrSt temporarily, Shannong87074-519 has very important value in wheat breeding and genetics improvement.