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The main aim of the work is to study the regulation of gene expression in the interaction between rice and Magnaporthe oryzae by gene chip technology. In this study, we mainly focused on changes of gene expression at 24, 48, and 72 hours post-inoculation (hpi), through which we could conduct a more comprehensive analysis of rice blast-related genes in the process of infection. The results showed that the experimental groups contained 460, 1227, and 3937 significant differentially expressed genes at 24, 48, and 72 hpi, respectively. Furthermore, 115 significantly differentially expressed genes were identified in response to rice blast infection at all three time points. By annotating these 115 genes, they were divided into three categories: metabolic pathways, proteins or enzymes, and organelle components. As expected, many of these genes were known rice blast-related genes; however, we discovered new genes with high fold changes. Most of them encoded conserved hypothetical proteins, and some were hypothetically conserved genes. Our study may contribute to finding new resistance genes and understanding the mechanism of rice blast development.

Chronic endometritis (CE) is a persistent and subtle local inflammatory disease characterized by abnormal plasma cell infiltration in the endometrial stroma.The incidence of chronic endometritis is as high as 15-57.5% in women suffering from infertility, implantation failure of in vitro fertilization (IVF) and unexplained recurrent abortion. Many studies both at home and abroad have shown that CE can reduce the receptivity of endometrium and affect embryo implantation. According to the existing reproductive immunity research, the abnormality of immune cell subsets in endometrium is an important factors leading to pregnancy failure. The immune microenvironment in endometrium consists of immune cells and immune molecules, and their influence on embryo implantation can not be ignored. This review paper discusses the controversy of pathogenesis, diagnosis and treatment of CE from the perspective of immune microenvironment by referring to related literature at home and abroad, and investigates the possible ways to improve the diagnosis and treatment of CE.

Background Maternally Expressed Gene 3 (MEG3) is expressed at low levels in placental villi during preeclampsia; however, its roles in unexplained recurrent spontaneous abortion (URSA) remain unclear. In this study, we aimed to explore the relationship between MEG3 and URSA. Methods The differentially expressed lncRNAs (MEG3) and its downstream genes (RASA1) were identified using bioinformatics analysis of Genomic Spatial Event (GSE) database. The expression levels of MEG3 in embryonic villis (with gestational ages of 49–63 days) and primary trophoblasts were determined using quantitative RT-PCR assay. A mouse model of Embryo implantation, Cell Counting Kit-8 (CCK-8), flow cytometry, and Transwell migration assays were performed to determine the implantation, proliferative, apoptotic, and invasive capacities of trophoblast. The level of phosphorylated core proteins in the RAS-MAPK pathway were analyzed using Western blot assay. The mechanisms of MEG3 in the regulation of RASA1 were studied by RNA pulldown, RNA immunoprecipitation (RIP), DNA pulldown, and chromatin immunoprecipitation (ChIP) assays. Results MEG3 had a low expression level in embryonic villis of 102 URSA patients compared with those of 102 normal pregnant women. MEG3 could promote proliferation and invasion, inhibit the apoptosis of primary trophoblast of URSA patients (PT-U cells), as well as promote embryo implantation of mouse. Besides, MEG3 also promoted the phosphorylation of rapidly accelerated fibrosarcoma (Raf), mitogen-activated protein kinase kinase (MEK), and extracellular-signal-regulated kinase (ERK) proteins. The results of RNA pull down and RIP assays showed that MEG3 bound with the enhancer of zeste homolog 2 (EZH2). The DNA pulldown assay revealed that MEG3 could bind to the promoter sequence of the RAS P21 Protein Activator 1 (RASA1) gene. Further, the ChIP assay showed that MEG3 promoted the binding of EZH2 to the promoter region of the RASA1 gene. Conclusions The inactivation of MEG3 in embryonic villi association with URSA; MEG3 inhibited the expression of RASA1 by mediating the histone methylation of the promoter of RASA1 gene by EZH2, thereby activating the RAS-MAPK pathway and enhancing the proliferative and invasive capacities of trophoblasts.

Some studies suggest that the inactivation of the Ras-MAPK pathway in trophoblast cells can lead to recurrent abortion, but the molecular mechanism underlying the inactivation of this pathway in trophoblast cells is still unclear. This study aimed to explore the relationship between the mechanism of abnormal activation of RASA1, a regulatory protein of the Ras-MAPK pathway, and unexplained recurrent spontaneous abortion. RT-qPCR was used to detect the transcription levels of RASA1 gene. Immunohistochemistry and Western blot were used to detect the expression levels of the RASA1, Raf and MEK proteins. CCK-8, TUNEL and Transwell assays were used to detect the proliferative, apoptotic, and invasive capacities of HTR-8/SVneo cells. ChIP assays were used to detect the enrichment of H3K27me3 in RASA1 gene promoter. Abortion villi experiments showed that the enrichment of H3K27me3 in the RASA1 gene promoter was reduced, and that both RASA1 gene transcription and RASA1 protein expression were increased. Cell experiments confirmed that RASA1 could decrease the phosphorylated Raf and MEK proteins, inhibit the proliferation and invasion ability, and promote the apoptosis ability of HTR-8/SVneo cells. It was also found that the proliferation and invasion ability as well as the Ras-MAPK pathway activity of HTR-8/SVneo cells were inhibited when treated with histone methyltransferase inhibitor DZNep. RASA1 gene was abnormally activated in unexplained recurrent spontaneous abortion villi due to the decreased enrichment of H3K27me3 in the gene promoter. High expression of RASA1 could inhibit the activity of the Ras-MAPK pathway, and thus inhibit the proliferation and invasion ability of trophoblast cells.

The main aim of the work is to study the regulation of gene expression in the interaction between rice and Magnaporthe oryzae by gene chip technology. In this study, we mainly focused on changes of gene expression at 24, 48, and 72 hours post-inoculation (hpi), through which we could conduct a more comprehensive analysis of rice blast-related genes in the process of infection. The results showed that the experimental groups contained 460, 1227, and 3937 significant differentially expressed genes at 24, 48, and 72 hpi, respectively. Furthermore, 115 significantly differentially expressed genes were identified in response to rice blast infection at all three time points. By annotating these 115 genes, they were divided into three categories: metabolic pathways, proteins or enzymes, and organelle components. As expected, many of these genes were known rice blast-related genes; however, we discovered new genes with high fold changes. Most of them encoded conserved hypothetical proteins, and some were hypothetically conserved genes. Our study may contribute to finding new resistance genes and understanding the mechanism of rice blast development., GRAPHICAL ABSTRACT

Fatty acids (FAs) have been implicated in signaling roles in plant defense responses. We previously reported that mutation or RNAi-knockdown (OsSSI2-kd) of the rice OsSSI2 gene, encoding a stearoyl acyl carrier protein FA desaturase (SACPD), remarkably enhanced resistance to blast fungus Magnaporthe oryzae and the leaf-blight bacterium Xanthomonas oryzae pv. oryzae (Xoo). Transcriptomic analysis identified six AAA-ATPase family genes (hereafter OsAAA-ATPase1&ndash, 6) upregulated in the OsSSI2-kd plants, in addition to other well-known defense-related genes. Here, we report the functional analysis of OsAAA-ATPase1 in rice&rsquo, s defense response to M. oryzae. Recombinant OsAAA-ATPase1 synthesized in Escherichia coli showed ATPase activity. OsAAA-ATPase1 transcription was induced by exogenous treatment with a functional analogue of salicylic acid (SA), benzothiadiazole (BTH), but not by other plant hormones tested. The transcription of OsAAA-ATPase1 was also highly induced in response to M. oryzae infection in an SA-dependent manner, as gene induction was significantly attenuated in a transgenic rice line expressing a bacterial gene (nahG) encoding salicylate hydroxylase. Overexpression of OsAAA-ATPase1 significantly enhanced pathogenesis-related gene expression and the resistance to M. oryzae, conversely, RNAi-mediated suppression of this gene compromised this resistance. These results suggest that OsAAA-APTase1 plays an important role in SA-mediated defense responses against blast fungus M. oryzae.

Rice blast, caused by Magnaporthe oryzae (M. oryzae), is one of the most destructive diseases in cultivated rice. The Wuling Mountain Area is marked as the key area for the national prevention and control of rice blast disease in China and is the ideal area for M. oryzae research according to its unique natural condition. In this study, a simple, low-cost and effective marker system including RAPD, REMAP, rep-PCR and Avr genes was developed for genetic diversity analysis of 108 M. oryzae isolates collected from the Wuling Mountain Area during 2012–2014. The results showed significant changes in the genetic structures of M. oryzae populations over the 3 years. However, there was no remarkably simple relationship between the genetic lineages and pathotypes (physiological races) of M. oryzae. The main mechanisms of M. oryzae to overcome host genes in the natural conditions of the Wuling Mountain Area might be point mutations or small deletions of gene sequences.

Due to its unique natural conditions, the Wuling Mountain region is a key area of prevention and control of rice blast disease in China and an ideal area for investigation of its causal fungus, Magnaporthe oryzae (M. oryzae) research. A total of 237 M. oryzae isolates collected from the Wuling Mountain region in 2017–2018 were used for the study of genetic diversity and pathogenicity dynamics. A set of differential varieties (DVs), including 7 Chinese DVs, 12 Japanese DVs and 21 monogenic lines, were established, which differentiate the 237 isolates in this study into different physiological races. Cluster analysis of the combined molecular marker system (RAPD, REMAP, rep-PCR and the avirulence (Avr) gene) results showed that Baiyang and Jianshi had the greatest genetic diversity, which is consistent with the pathogenic results. The proportion of the two mating types was roughly equal each year; however, the dominance of the mating type between the two years was opposite. Furthermore, four isolates contained both mating types, which were assumed to be dual maters. Isolates with amplified bands of Avr genes (Avr-Pizt and Avr-Pita) and corresponding pathogenicity were selected for Sanger sequencing. The result showed that point mutations and small indels resulted in the loss of avirulence function, indicating that mutations are potential mechanism for the rich pathogenic and genetic diversity of M. oryzae in the Wuling Mountain region.

Rice blast resistance caused by Resistance (R) genes, most of which encode coiled-coil (CC), nucleotide-binding (NB), and leucine-rich-repeat (LRR) domains, is race-specific. Panicle blast 1 (Pb1) is a panicle blast resistance gene that confers a durable non-race-specific blast resistance to rice. Despite being non-R, Pb1 also encodes a CC-NB-LRR protein. Pb1 specifically interacts with rice WRKY45, a transcription factor (TF) in the rice salicylic acid signaling pathway, through its CC domain, and that this interaction is important for the blast resistance conferred by Pb1. Additionally, barley MLA10, an R protein for Blumeria graminis, specifically interacts with HvWRKY1/2. Here, we investigated whether the blast resistance between conferred by R genes and non-R Pb1 genes is mediated by their interaction with WRKY TFs. We performed targeted yeast two-hybrid and glutathione S-transferase (GST)-pull-down assays, which showed that all the five rice R proteins of the CC-NB-LRR type tested, Pi36, Pib, Pita, Pit, and Piz-t, interacted with WRKY45 and WRKY66 through their CC domains. However, elicitor-triggered immunity due to these R genes was not affected by the knockdown of these WRKY genes. The results suggest that R proteins can potentially transduce defense signals by interacting with WRKY TFs but the potentials are masked by HR-mediated elicitor-triggered immunity responses.

Blast, caused by the ascomycete fungus Magnaporthe oryzae, is one of the most devastating diseases of rice due to the high variation of the pathogen. Breeding high-yielding rice cultivar with durable resistance to rice blast is a priority in Southern China and in places where rice cultivation is an important branch in farming. Effectiveness and accuracy of resistant cultivar breeding largely depend on the development of markers specific to the target gene. In silico prediction of the resistance (R) Pi39 gene content of the interval was made and hence a candidate gene was identified to develop a perfect insertion–deletion (InDel) based marker for Pi39 gene selection. The Pi39 gene was successfully introgressed in two elite cultivars using both foreground (the InDel) and background (genome-wide microsatellites) genotypic and phenotypic selection. Five selected BC3F3 progeny lines were recovered and showed a high level of blast resistance. At least 97.5% of their genome was inherited from their recurrent par...

In response to pathogen attack, plants prioritize defense reactions generally at the expense of plant growth. In this work, we report that changes in phytohormone signaling pathways are associated with the stunted plant growth caused by blast disease in rice seedlings. Infection of rice seedlings with blast fungus Magnaporthe oryzae (race 007.0) at the four-leaf stage (three true leaves) resulted in considerable inhibition of the growth of the upper uninfected distal leaves; the length of leaf blade and leaf sheath of the sixth and seventh leaf was reduced by 27 and 82%, and 88 and 72%, respectively, compared to that in the uninoculated plant control. Interestingly, cutting off the blast-infected fourth leaf blade within 2 days post inoculation (dpi) significantly rescued the inhibition of leaf growth, implying that an inhibitory substance(s) and/or signal was generated in the blast-infected leaves (fourth leaf) and transmitted to the upper distal leaves (sixth and seventh) during the 2-dpi period that induced growth inhibition. Expression analysis of marker genes for phytohormone pathways revealed acute activation of the jasmonate (JA) and abscisic acid (ABA) signaling pathways, and repression of auxin, gibberellic acid (GA) and salicylic acid (SA) signaling pathways, in the sixth leaf. The genes related to cell wall expansion were also significantly downregulated. In the blast-infected fourth leaf, JA pathway was activated within 2 dpi, followed by activation of ABA pathway 3 dpi. Further, leaf inhibition caused by blast infection was partially rescued in the rice mutant line coleoptile photomorphogenesis 2 (cpm2), which is defective in the gene encoding allene oxide cyclase (OsAOC). These results indicate that the JA signaling pathway is at least partly involved in the growth inhibition processes. Collectively, our data suggest that, upon pathogen attack, rice seedlings prioritize defense reactions against the infecting pathogen by temporarily ceasing plant growth through the systemic control of phytohormone pathways.

Rice blast resistance (R) genes-mediated resistance response depends on various resistance-related genes involved in incompatible interactions. In this work, the expression profiles of innate rice immunity related genes were examined in the mediated resistance response of true/field resistance genes. Three sets of rice near-isogenic lines (NILs) were used: the resistant NILs carrying true resistance genes in the genetic background of the susceptible cultivar Nipponbare (NB), NB-Pib, NB-Pizt, NB-Pik and NB-Pita2; NILs bearing field resistance genes pi21 in the susceptible cultivar Aichiasahi (AA) AA-pi21, Kahei (KHR). The marker gene OsWRKY45 of salicylic acid (SA) signalling was upregulated in all tested cultivars. And, JAmyb (marker gene of jasmonic acid signalling) showed higher upregulation in the resistance lines with nucleotide-binding sites and leucine-rich repeat (NBS-LRR) R genes Pib, Pizt, Pik, Pita2 and Pikahei than in NB and KHS. SalT of abscisic acid (ABA) signalling may be involved in the R/Avr interaction, including Pizt, Pik, pi21 and Pikahei. However, SalT was shown to negatively regulate Pib/AvrPib interaction. OsPR1b and PBZ1 were differentially expressed and strongly activated at a later stage by 48 h post-inoculation. Interestingly, there was evidence that OsPR1b and PBZ1 played an important role in the pi21-mediated response. It was shown that OsRAR1 could be upregulated in the true resistance line NB-Pita2 and the field resistance line KHR, while OsSGT1 and OsHSP90 could be upregulated in all tested lines. The involvement of these genes illustrated the complexity of the downstream signalling pathways in the mediated resistance response of true/field resistance genes.

Hormone crosstalk is pivotal in plant–pathogen interactions. Here, we report on the accumulation of cytokinins (CK) in rice seedlings after infection of blast fungus Magnaporthe oryzae and its potential significance in rice–M. oryzae interaction. Blast infection to rice seedlings increased levels of N6-(Δ2-isopentenyl) adenine (iP), iP riboside (iPR), and iPR 5′-phosphates (iPRP) in leaf blades. Consistent with this, CK signaling was activated around the infection sites, as shown by histochemical staining for β-glucuronidase activity driven by a CK-responsive OsRR6 promoter. Diverse CK species were also detected in the hyphae (mycelium), conidia, and culture filtrates of blast fungus, indicating that M. oryzae is capable of production as well as hyphal secretion of CK. Co-treatment of leaf blades with CK and salicylic acid (SA), but not with either one alone, markedly induced pathogenesis-related genes OsPR1b and probenazole-induced protein 1 (PBZ1). These effects were diminished by RNAi-knockdown of OsNPR1 or WRKY45, the key regulators of the SA signaling pathway in rice, indicating that the effects of CK depend on these two regulators. Taken together, our data imply a coevolutionary rice–M. oryzae interaction, wherein M. oryzae probably elevates rice CK levels for its own benefits such as nutrient translocation. Rice plants, on the other hand, sense it as an infection signal and activate defense reactions through the synergistic action with SA.

Plant basic leucine zipper (bZIP) proteins play an essential role in the genes expression and regulation in higher plants. They have been shown to regulate diverse plant specific phenomena, including germination, floral induction and development, seed maturation, photomorphogenesis, biotic and abiotic stresses. Resistance response mediated by the rice blast resistance gene Pi36 is a typical signal transduction, in which 12 OsbZIP genes were differentially expressed by microarray analyses. To understand the potential function of OsbZIP genes during the defense responses against rice blast, the expression analysis of these OsbZIP genes, in response to the blast fungus inoculation and the related defense signal molecules induction, were further conducted using real-time fluorescent quantitative polymerase chain reaction (PCR) technique. Our data indicates that among the 12 OsbZIP genes, the expression level eight tested genes were differentially regulated and maintained to 96 h points post inoculation in rice resistant and susceptible cultivars during Magnaporthe oryzae infection, and all of them were also significantly up-regulated by one or several kinds of exogenous plant hormones stresses. Although, these genes were induced only at early time points (1 to 24 h); it is evident that the OsbZIP genes may be involved in different signaling pathway, and play potential important functions in the defense response to rice blast. Keywords: OsbZIP transcription factors, rice blast, resistance response, plant hormones stresses. African Journal of Biotechnology Vol. 12(34), pp. 5294-5302

A new bacterial blight recessive resistance gene xa34(t) was identified from the descendant of somatic hybridization between an aus rice cultivar (cv.) BG1222 and susceptible cv. IR24 against Chinese race V (isolate 5226). The isolate was used to test the resistance or susceptibility of F(1) progenies and reciprocal crosses of the parents. The results showed that F(1) progenies appeared susceptibility there were 128R (resistant):378S (susceptible) and 119R:375S plants in F(2) populations derived from two crosses of BG1222/IR24 and IR24/BG1222, respectively, which both calculates into a 1R:3S ratio. 320 pairs of stochastically selected SSR primers were used for genes' initial mapping. The screened results showed that two SSR markers, RM493 and RM446, found on rice chromosome 1 linked to xa34(t). Linkage analysis showed that these two markers were on both sides of xa34(t) with the genetic distances 4.29 and 3.05 cM, respectively. The other 50 SSR markers in this region were used for genes' fine mapping. The further results indicated that xa34(t) was mapped to a 1.42 cM genetic region between RM10927 and RM10591. In order to further narrow down the genomic region of xa34(t), 43 of insertion/deletion (Indel) markers (BGID1-43) were designed according to the sequences comparison between japonica and indica rice. Parents' polymorphic detection and linkage assay showed that the Indel marker BGID25 came closer to the target gene with a 0.4 cM genetic distance. A contig map corresponding to the locus was constructed based on the reference sequences aligned by the xa34(t) linked markers. Consequently, the locus of xa34(t) was defined to a 204 kb interval flanked by markers RM10929 and BGID25.

The resistance gene Pi36 confers a stable and high level of resistance against Chinese isolates of the rice blast pathogen Magnaporthe oryzae. Quantitative real time RT-PCR was used to investigate the expression profiles of various resistance-related genes in both the Pi36/AvPi36 incompatible interactions. Among 17 members of the OsMAPK family, OsMAPK2, OsMAPK4, OsMAPK8 and OsMAPK15 were differentially expressed, as were OsWRKY30, OsWRKY32, OsWRKY64 and OsWRKY67 among the 13 OsWRKY members studied. The induction of the expression of genes from both of these families suggests that both the JA and SA pathways are involved in Pi36-mediated defence. Other genes differentially expressed included the OsbZIP transcription factors, OsNIF1 and OsNIF2, and the NPR1 homologue OsNH2, all of which were reported in the rice blast pathosystem. The involvement of these genes illustrates the complexity of the downstream signalling pathways involved in the Pi36/AvrPi36 interaction.

A plasmid (pCW) was modified to code for the complete sequence of house fly (Musca domestica) cytochrome P450 6A1 (CYP6A1) with only the second amino acid changed in the N-terminal portion and this plasmid was used to express the enzyme CYP6A1 in Escherichia coli cells. With the addition of delta-aminolevulinic acid and FeCl(3) to the culture, the enzyme was produced at a level about 0.25 micromol L(-1) (15mgL(-1)) of culture with approximately 50% of the P450 being associated with the membrane fraction. The CYP6A1 protein was characterized and the content of CYP6A1 in each fraction was determined by the spectroscopic method. A nearly homogenous CYP6A1 was obtained by purification with a combination of DEAE Sepharose fast flow and hydroxyapatite chromatography. Direct electrochemistry of CYP6A1 in a didodecyldimethylammonium bromide (DSAB) film on an edge-plane pyrolytic graphite electrode (EPG) has been obtained and the catalytic activity of the enzyme to aldrin has been demonstrated by the cyclic voltammetry.

The resistance (R) gene Pi37, present in the rice cultivar St. No. 1, was isolated by an in silico map-based cloning procedure. The equivalent genetic region in Nipponbare contains four nucleotide binding site–leucine-rich repeat (NBS–LRR) type loci. These four candidates for Pi37 (Pi37-1, -2, -3, and -4) were amplified separately from St. No. 1 via long-range PCR, and cloned into a binary vector. Each construct was individually transformed into the highly blast susceptible cultivar Q1063. The subsequent complementation analysis revealed Pi37-3 to be the functional gene, while -1, -2, and -4 are probably pseudogenes. Pi37 encodes a 1290 peptide NBS–LRR product, and the presence of substitutions at two sites in the NBS region (V239A and I247M) is associated with the resistance phenotype. Semiquantitative expression analysis showed that in St. No. 1, Pi37 was constitutively expressed and only slightly induced by blast infection. Transient expression experiments indicated that the Pi37 product is restricted to the cytoplasm. Pi37-3 is thought to have evolved recently from -2, which in turn was derived from an ancestral -1 sequence. Pi37-4 is likely the most recently evolved member of the cluster and probably represents a duplication of -3. The four Pi37 paralogs are more closely related to maize rp1 than to any of the currently isolated rice blast R genes Pita, Pib, Pi9, Pi2, Piz-t, and Pi36.

The gene Pi15 for resistance of rice to Magnaporthe grisea was previously mapped to a ≈0.7-cM region on chromosome 9. To further define the chromosomal region of the Pi15 locus, a contig spanning the locus was constructed, in silico,through bioinformatics analysis using a reference sequence of the cultivar 'Nipponbare'. One simple sequence repeat marker adopted from the International Rice Microsatellite Initiative and six candidate resistance gene (CRG) markers, developed from gene annotation of the reference sequence of the contig, were used for linkage analysis in a mapping population consisting of 504 extremely susceptible F 2 plants. The Pil5 locus was delimited to a ≈0.5-cM region flanked by the markers CRG5 and CRG2 and co-segregated with the markers BAPi15 782 , CRG3 and CRG4, which was physically converted to a 44-kb interval.

Blast resistance in the indica cultivar (cv.) Q61 was inherited as a single dominant gene in two F2 populations, F2-1 and F2-2, derived from crosses between the donor cv. and two susceptible japonica cvs. Aichi Asahi and Lijiangxintuanheigu (LTH), respectively. To rapidly determine the chromosomal location of the resistance (R) gene detected in Q61, random amplified polymorphic DNA (RAPD) analysis was performed in the F2-1 population using bulked-segregant analysis (BSA) in combination with recessive-class analysis (RCA). One of the three linked markers identified, BA1126(550), was cloned and sequenced. The R gene locus was roughly mapped on rice chromosome 8 by comparison of the BA1126(550) sequence with rice sequences in the databases (chromosome landing). To confirm this finding, seven known markers, including four sequence-tagged-site (STS) markers and three simple-sequence repeat (SSR) markers flanking BA1126(550) on chromosome 8, were subjected to linkage analysis in the two F2 populations. The locus was mapped to a 5.8 cM interval bounded by RM5647 and RM8018 on the short arm of chromosome 8. This novel R gene is therefore tentatively designated as Pi36(t). For fine mapping of the Pi36(t) locus, five additional markers including one STS marker and four candidate resistance gene (CRG) markers were developed in the target region, based on the genomic sequence of the corresponding region of the reference japonica cv. Nipponbare. The Pi36(t) locus was finally localized to an interval of about 0.6 cM flanked by the markers RM5647 and CRG2, and co-segregated with the markers CRG3 and CRG4. To physically map this locus, the Pi36(t)-linked markers were mapped by electronic hybridization to bacterial artificial chromosome (BAC) or P1 artificial chromosome (PAC) clones of Nipponbare, and a contig map was constructed in silico through Pairwise BLAST analysis. The Pi36(t) locus was physically delimited to an interval of about 17.0 kb, based on the genomic sequence of Nipponbare.

The elite rice cultivar Yuejingsimiao 2 (YJ2) is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance (R) gene donor cultivars such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F(2) and F(4) populations indicated the resistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a bulked-segregant analysis using genome-wide selected SSR markers with F(4) lines that segregated into 3 resistant (R):1 susceptible (S) or 1R:3S. The recessive R gene on chromosome 8 was further mapped to an interval ≈1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F(4) line that segregated into 1R:3S. Given that no major R gene was mapped to this interval, the novel R gene was designated as pi55(t). Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metal-associated domain-containing protein, respectively, were suggested as the most likely candidates for pi55(t).

For automatic service composition, a planning based framework MOCIS is proposed. Planning is based on two major techniques, service reasoning and constraint satisfaction. Constraint satisfaction can be divided into quality constraint satisfaction and quantity constraint satisfaction. Contrary to traditional methods realizing upon techniques by interleaving activity, message and provider, the novelty of the framework is dividing these concerns into three layers, with activity layer majoring service reasoning, message layer for quality constraint and provider layer for quantity constraint. The layered architecture makes automatic web service composition possible for activity tree that abstract BPEL list and concrete BPEL list are achieved automatically with each layer, and users can selection proper abstract BPEL or BPEL to satisfy their request. And E-traveling composition cases have been tested, demonstrating that complex service can be achieved through three layers compositing automatically.

The paper reviews the characteristics of geological disasters in Three Gorges reservoir area and the bandwidth of the communication lines, as well as the functions and the effects of emergency rescue system. The thesis briefly describes the target and content of the monitoring and prediction of the emergent geological disasters commanding platform, and also gives the data flow analysis of its subsystems emergency — commanding car, upon which the overall system block diagram design of the commanding car can be achieved. According to the mainly indexes of the system requirements, we analyze the functions of its sub-modules, and finally implement the system. The spot test shows that the design of this system is reliable, security and strong, of which the voice is clear, the images are smooth, the data transmission is stable.

A blind audio watermarking algorithm in the time domain is proposed. The audio signal is divided into frames and the watermark is inserted on a frame by frame basis. The proposed algorithm detects the watermark using a signal processor based on the stochastic resonance mechanism. The watermark detection does not need the original audio. The parameter-induce stochastic resonance in audio watermarking is observed and the interpretation to this phenomenon is given. For the synchronization attack, the experimental results show that the stochastic resonance signal processor can catch up and surpass the performance of the matched filter. This reveals a robustness superiority of the stochastic resonance signal processor, compared to the matched filter operating outside its strict nominal conditions, which is especially helpful for the audio watermarking.

The paper addresses the noise image which adopts the embedded zerotree wavelet coding algorithm to compress and then results in decreasing the amount of the zerotree and increasing the amount of the alone-zero, which will affect the compression effect. Therefore this paper brings forward the characteristic directional median filter to reduce noise before the noise image compression; aim at solving the insufficiency of the scope table order frequent adjusts in the EZW algorithm, we proposes to adopt adaptive depth first search strategy through definition floating threshold. The result shows that the new image compression scheme has improved better than traditional EZW algorithm in the aspects of image quality, compression effect and compression coding efficiency.

Due to the problem of detecting weak signal in strong noise, a method of pulse signal detection was put forward which is based on multiresolution wavelet analysis. According to Parserval theorem, the frame of signal space decomposition and energy distributing was established by this method, and a complete orthogonal multi-resolution description is defined, the design of floating threshold of multiresolution wavelet analysis was discussed, and the removing noise algorithm has been given. The result of experiment and emulation shows that multi-band wavelet analysis is able to extract the weak and unclear pulse signal from white noise. This method is applied to laser pulse exploration system, and which has better effect.

The indica rice variety Kasalath carries Pi36, a gene that determines resistance to Chinese isolates of rice blast and that has been located to a 17-kb interval on chromosome 8. The genomic sequence of the reference japonica variety Nipponbare was used for an in silico prediction of the resistance (R) gene content of the interval and hence for the identification of candidate gene(s) for Pi36. Three such sequences, which all had both a nucleotide-binding site and a leucine-rich repeat motif, were present. The three candidate genes were amplified from the genomic DNA of a number of varieties by long-range PCR, and the resulting amplicons were inserted into pCAMBIA1300 and/or pYLTAC27 vectors to determine sequence polymorphisms correlated to the resistance phenotype and to perform transgenic complementation tests. Constructs containing each candidate gene were transformed into the blast-susceptible variety Q1063, which allowed the identification of Pi36-3 as the functional gene, with the other two candidates being probable pseudogenes. The Pi36-encoded protein is composed of 1056 amino acids, with a single substitution event (Asp to Ser) at residue 590 associated with the resistant phenotype. Pi36 is a single-copy gene in rice and is more closely related to the barley powdery mildew resistance genes Mla1 and Mla6 than to the rice blast R genes Pita, Pib, Pi9, and Piz-t. An RT–PCR analysis showed that Pi36 is constitutively expressed in Kasalath.

Blast, caused by the ascomycete fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. The Chinese native cultivar (cv.) Q15 expresses the broad-spectrum resistance to most of the isolates collected from China. To effectively utilize the resistance, three rounds of linkage analysis were performed in an F2 population derived from a cross of Q15 and a susceptible cv. Tsuyuake, which segregated into 3:1 (resistant/susceptible) ratio. The first round of linkage analysis employing simple sequence repeat (SSR) markers was carried out in the F2 population through bulked-segregant assay. A total of 180 SSR markers selected from each chromosome equally were surveyed. The results revealed that only two polymorphic markers, RM247 and RM463, located on chromosome 12, were linked to the resistance (R) gene. To further define the chromosomal location of the R gene locus, the second round of linkage analysis was performed using additional five SSR markers, which located in the region anchored by markers RM247 and RM463. The locus was further mapped to a 0.27 cM region bounded by markers RM27933 and RM27940 in the pericentromeric region towards the short arm. For fine mapping of the R locus, seven new markers were developed in the smaller region for the third round of linkage analysis, based on the reference sequences. The R locus was further mapped to a 0.18 cM region flanked by marker clusters 39M11 and 39M22, which is closest to, but away from the Pita/Pita 2 locus by 0.09 cM. To physically map the locus, all the linked markers were landed on the respective bacterial artificial chromosome clones of the reference cv. Nipponbare. Sequence information of these clones was used to construct a physical map of the locus, in silico, by bioinformatics analysis. The locus was physically defined to an interval of ≈37 kb. To further characterize the R gene, five R genes mapped near the locus, as well as 10 main R genes those might be exploited in the resistance breeding programs, were selected for differential tests with 475 Chinese isolates. The R gene carrier Q15 conveys resistances distinct from those conditioned by the carriers of the 15 R genes. Together, this valuable R gene was, therefore, designated as Pi39(t). The sequence information of the R gene locus could be used for further marker-based selection and cloning.