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Rock-like materials can be used as a filling material to improve the stability of underground engineering substantially. And the optimization of the rock-like material is an effective way to improve the performance of the filling material. Firstly, the AHP-FUZZY comprehensive optimization model was constructed for the complexity and fuzziness of the rock-like filling material ratio optimization. Secondly, according to the mechanical properties of rock-like filling materials under special environment (such as high temperature, high humidity, high stress, and high airtight) in old goaf, mechanical properties of rock-like filling materials were studied with the method of field core and laboratory test, which revealed the variation law of mechanical properties with time, and the regression equation between mechanical parameters and time was established with the method of least squares. Finally, the strength and deformation characteristics of rock-like filling materials were monitored by the monitoring and early warning technology. The results show that the optimal ratio of the rock-like filling materials is "E3"; that is, the cement content is 9%, the ash ratio is 2 : 5, and the mass concentration is 74%. The mass concentration is the main factor that affects the slump of the slurry, and the proportion of fly ash and coal gangue content directly affects the stratification and bleeding rate of the slurry. Reasonably increasing the ash and gangue ratio can significantly improve the workability and water retention of the rock-like filling materials. Also, the amount of composite cementitious material is the main factor that affects the setting time and the strength of the rock-like material. What is more, the special environment in gob is good for each chemical reaction fully in rock-like filling materials and strengthens the gelling property of deformation resisting capability, which can be a benefit for disaster prevention of underground engineering. [ABSTRACT FROM AUTHOR]

Purpose: Federal crop insurance programs are the primary risk management programs of the US farm programs. Currently, these programs have been criticized for being disproportionally in favor of the riskier areas. Despite previous researchers having widely speculated its existence, a formal study of the scale, spatial pattern and fiscal impacts of such misrating phenomenon is still missing in the literature. Design/methodology/approach: This paper first purposes an empirically testable definition of misrating, and then detects the scale of the misrating phenomenon by using over two million actuarial records collected by United States Department of Agriculture (USDA's) risk management agency since 1989. Furthermore, multiple spatial statistics methods have been adopted to study the spatial patterns of the misrating statuses. Finally, the paper builds a simple theoretical model to study the potential fiscal impacts of any policy attempts to mitigate the misrating issue. Findings: The result reveals that roughly 40% of the counties display some degree of misrating. Furthermore, the distribution of misrating displays a significant pattern of positive global spatial autocorrelation, which reflects the existence of regional clusters of premium rate mispricing. Last but not least, the paper concludes that whether an attempt toward fair rating decreases the total program outlay or not relies on the demand elasticity of crop insurance in both overrated and underrated regions. Originality/value: This paper offers the first attempt to quantify the scale, identify the spatial pattern and evaluate the fiscal impact of the premium misrating in federal crop insurance programs. [ABSTRACT FROM AUTHOR]

• Spatial interaction effects influence the inland distribution maritime flows. • The presence of spatial interaction effects reveals direct and network effects. • GDP and travel time are key to the inter-port distribution of traffic. • For exports, spillovers are greater for GDP and travel time. • For imports, spillovers are greater for throughput. The relationship between the regional economy and the infrastructure endowment has long been discussed in the literature. In this context, it can be said that ports play an important role for regions, as they affect their competitiveness, while the regional economic activity has an effect on port traffic. Both circumstances influence the inland distribution of maritime traffic and are interconnected by the configuration of the hinterland of ports. The hypothesis of this paper is that spatial interaction effects, both exogenous and endogenous, shape the inter-port distribution of maritime traffic. The endogenous interaction effect arises when the inter-port distribution of the flows is influenced by those of nearby regions, whereas the exogenous interaction effect appears when the circumstances of these neighbours affect the flows generated by the region considered. The inter-port distribution of Spanish maritime flows of foreign trade for the period 1995–2015 was analysed in order to confirm the validity of this hypothesis. To that end, the Spatial Econometric Interaction Modelling (SEIM) framework was followed, and a Spatial Durbin Model (SDM) to origin-destination flows was applied. The results confirm that endogenous and exogenous interaction effects impact the inland distribution of the Spanish container flows and reveal the existence of direct and network effects regarding the variables analysed. [ABSTRACT FROM AUTHOR]

Low temperature affects plant growth and crop productivity. The CBF genes are a class of transcription factors that play important roles in cold response. Here we report that AtMYB14 participates in freezing tolerance in Arabidopsis by affecting expression of CBF genes. The AtMYB14 gene was down-regulated by cold treatment. AtMYB14 encodes a nuclear protein that functions as an R2R3-MYB transcription activator. Knock-down of AtMYB14 by artificial microRNA increased the tolerance to freezing stress. Both the CBF genes and the downstream genes were induced to a much higher level in AtMYB14 knock-down plants than in wild type under cold treatment. Our results suggest that AtMYB14 plays an important role in the plant response to cold stress. [ABSTRACT FROM AUTHOR]

Reports the potential existence of receptors outside the cell wall of the calmodulin (CaM). Methods used in the study; How cell wall proteins were isolated; Results of the study.

Cover crops have been reported as one of the most effective practices to increase soil organic carbon (SOC) for agroecosystems. Impacts of cover crops on SOC change vary depending on soil properties, climate, and management practices, but it remains unclear how these control factors affect SOC benefits from cover crops, as well as which management practices can maximize SOC benefits. To address these questions, we used an advanced process‐based agroecosystem model, ecosys, to assess the impacts of winter cover cropping on SOC accumulation under different environmental and management conditions. We aimed to answer the following questions: (1) To what extent do cover crops benefit SOC accumulation, and how do SOC benefits from cover crops vary with different factors (i.e., initial soil properties, cover crop types, climate during the cover crop growth period, and cover crop planting and terminating time)? (2) How can we enhance SOC benefits from cover crops under different cover crop management options? Specifically, we first calibrated and validated the ecosys model at two long‐term field experiment sites with SOC measurements in Illinois. We then applied the ecosys model to six cover crop field experiment sites spanning across Illinois to assess the impacts of different factors on SOC accumulation. Our modeling results revealed the following findings: (1) Growing cover crops can bring SOC benefits by 0.33 ± 0.06 MgC ha−1 year−1 in six cover crop field experiment sites across Illinois, and the SOC benefits are species specific to legume and non‐legume cover crops. (2) Initial SOC stocks and clay contents had overall small influences on SOC benefits from cover crops. During the cover crop growth period (i.e., winter and spring in the US Midwest), high temperature increased SOC benefits from cover crops, while the impacts from larger precipitation on SOC benefits varied field by field. (3) The SOC benefits from cover crops can be maximized by optimizing cover crop management practices (e.g., selecting cover crop types and controlling cover crop growth period) for the US Midwestern maize–soybean rotation system. Finally, we discussed the economic and policy implications of adopting cover crops in the US Midwest, including that current economic incentives to grow cover crops may not be sufficient to cover costs. This study systematically assessed cover crop impacts for SOC change in the US Midwest context, while also demonstrating that the ecosys model, with rigorous validation using field experiment data, can be an effective tool to guide the adaptive management of cover crops and quantify SOC benefits from cover crops. The study thus provides practical tools and insights for practitioners and policy‐makers to design cover crop related government agricultural policies and incentive programs for farmers and agri‐food related industries. [ABSTRACT FROM AUTHOR]

Discusses advances in plant biotechnology in China. Plant biotechnology in government's National High Technology Plan; Financial assistance from foreign governments and international organizations; Development of pathogen-resistant plants.

Cover crops have critical significance for agroecosystem sustainability and have long been promoted in the U.S. Midwest. Knowledge of cover cropping variations and impacts of government policies remains very limited. We developed an accurate and cost‐effective approach utilizing satellite fusion data, environmental variables, and machine learning to quantify cover cropping in corn and soybean fields from 2000 to 2021 in the U.S. Midwest. We found that cover crop adoption in most counties was stagnant from 2000 to 2011, but has significantly increased from 2011 to 2021. The adoption of 2021 is four times that of 2011, which was highly correlated to the funding for conservation programs. However, the percentage of cover crop adoption in the U.S. Midwest is still low (7.2%). Our work fills a critical gap in quantifying long‐term field‐level cover crop adoption at large regions and highlights the potential importance of incentive programs to promote sustainable agricultural practices. Plain Language Summary: Cover crops typically grow after cash crop harvesting and before the following season's planting of cash crops, and can bring benefits to agricultural sustainability. To stimulate cover crop adoption in the U.S. Midwest, the U.S. government has made significant financial and technical support to farmers for cover cropping (e.g., USDA Environmental Quality Incentives Program invested over $14 billion in conservation practices from 2010 to 2020). However, large‐scale and long‐term cover cropping information in the U.S. Midwest is largely missing. Timely and cost‐effective monitoring and verification of cover crop adoption are urgently needed. We utilized multi‐source remote sensing data and large amounts of ground truth data to develop effective approaches to detect cover crop adoption from 2000 to 2021 in a cost‐effective manner. We found that cover cropping acreage has significantly increased four times from 2011 to 2021. We also found the increase in cover crop adoption is highly correlated to the funding from federal and state conservation programs. The incentive programs could play an important role in promoting sustainable agricultural practices. Key Points: We developed a scalable remote sensing framework to detect field‐level cover cropping in the U.S. Midwest from 2000 to 2021Cover cropping adoption rate in the U.S. Midwest has significantly increased by four‐fold from 1.8% in 2011% to 7.2% in 2021Cover cropping rate is highly correlated to the incentives of federal and state conservation programs [ABSTRACT FROM AUTHOR]

Rice blast disease is a major threat to rice production worldwide, but the mechanisms underlying rice resistance to the causal agent Magnaporthe oryzae remain elusive. Therefore, we carried out a transcriptome study on rice early defense response to M. oryzae. We found that the transcriptional profiles of rice compatible and incompatible interactions with M. oryzae were mostly similar, with genes regulated more prominently in the incompatible interactions. The functional analysis showed that the genes involved in signaling and secondary metabolism were extensively up-regulated. In particular, WRKY transcription factor genes were significantly enriched among the up-regulated genes. Overexpressing one of these WRKY genes, OsWRKY47, in transgenic rice plants conferred enhanced resistance against rice blast fungus. Our results revealed the sophisticated transcriptional reprogramming of signaling and metabolic pathways during rice early response to M. oryzae and demonstrated the critical roles of WRKY transcription factors in rice blast resistance. [ABSTRACT FROM AUTHOR]

Abstract: Soil salinity significantly limits plant productivity on agricultural lands, and salt tolerance of plant requires a complex mechanism in which many genes are involved. From an activation-tagging mutant collection, we identified a loss-of-function Arabidopsis mutant which exhibits hypersensitivity to NaCl during seed germination and is designated ssg1 (salt sensitive during seed germination 1). Knocking down the expression of SSG1 by RNAi recapitulated the phenotype of ssg1, suggesting that functional SSG1 is necessary for normal seed germination in the presence of NaCl. The seed germination of ssg1 was not sensitive to K+, but was hypersensitive to osmotic stress. SSG1 encodes a protein kinase, possibly with alternatively spliced forms. In vitro kinase assay indicated that SSG1 possessed protein kinase activity which can both auto-phosphorylate and phosphorylate substrate. Quantitative real-time RT-PCR analysis showed that, in the mutants ssg1-1 and ssg1-2, the expression level of some salt-responsive marker genes, i.e., SOS1, SOS2, SOS3, SOS4, AtNHX and AtNKT, was down-regulated, whereas SSG1 expression level was not changed in sos mutants. These results suggest that SSG1 is possibly a component in the signaling pathway in response of plants to salt stress. [Copyright &y& Elsevier]

Ethylene plays a crucial role in plant resistance to necrotrophic pathogens, in which ETHYLENE RESPONSE FACTORs (ERFs) are often involved., Here, we evaluated the role of an ERF transcription factor, RELATED TO AP2 2 (RAP2.2), in Botrytis resistance and ethylene responses in Arabidopsis. We analyzed the resistance of transgenic plants overexpressing RAP2.2 and the T-DNA insertion mutant to Botrytis cinerea. We assessed its role in the ethylene signaling pathway by molecular and genetic approaches., RAP2.2-overexpressing transgenic plants showed increased resistance to B. cinerea, whereas its T-DNA insertion mutant rap2.2-3 showed decreased resistance. Overexpression of RAP2.2 in ethylene insensitive 2 ( ein2) and ein3 ein3-like 1 ( eil1) mutants restored their resistance to B. cinerea. Both ethylene and Botrytis infection induced the expression of RAP2.2 and the induction was disrupted in ein2 and ein3 eil1 mutants. We identified rap2.12-1 as a T-DNA insertion mutant of RAP2.12, the closest homolog of RAP2.2. The hypocotyls of rap2.2-3 rap2.12-1 double mutants showed ethylene insensitivity. The constitutive triple response in constitutive triple response1 ( ctr1) was partially released in the rap2.2-3 rap2.12-1 ctr1 triple mutants., Our findings demonstrate that RAP2.2 functions as an important regulator in Botrytis resistance and ethylene responses. [ABSTRACT FROM AUTHOR]

Summary The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that is involved in regulating cell-cycle progression. It has been widely studied in yeast and animal cells, but the function and regulation of the APC/C in plant cells are largely unknown. The Arabidopsis APC/C comprises at least 11 subunits, only a few of which have been studied in detail. APC4 is proposed to be a connector in the APC/C in yeast and animals. Here, we report the functional characterization of the Arabidopsis APC4 protein. We examined three heterozygous plant lines carrying apc4 alleles. These plants showed pleiotropic developmental defects in reproductive processes, including abnormal nuclear behavior in the developing embryo sac and aberrant cell division in embryos; these phenotypes differ from those reported for mutants of other subunits. Some ovules and embryos of apc4/ + plants also accumulated cyclin B protein, a known substrate of APC/C, suggesting a compromised function of APC/C. Arabidopsis APC4 was expressed in meristematic cells of seedlings, ovules in pistils and embryos in siliques, and was mainly localized in the nucleus. Additionally, the distribution of auxin was distorted in some embryos of apc4/ + plants. Our results indicate that Arabidopsis APC4 plays critical roles in female gametogenesis and embryogenesis, possibly as a connector in APC/C, and that regulation of auxin distribution may be involved in these processes. [ABSTRACT FROM AUTHOR]

In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self‐maintenance and organ initiation, which are separated spatially in meristem. Prior to our study, WUS and WUS‐like WOX genes had been reported as essential for the development of the SAM. In this study, the consequences of gain of WOX1 function are described. Here we report the identification of an Arabidopsis gain‐of‐function mutant wox1‐D, in which the expression level of the WOX1 (WUSCHEL HOMEOBOX 1) was elevated and subtle defects in meristem development were observed. The wox1‐D mutant phenotype is dwarfed and slightly bushy, with a smaller shoot apex. The wox1‐D mutant also produced small and dark green leaves, and exhibited a failure in anther dehiscence and male sterility. Molecular evidences showed that the transcription of the stem cell marker gene CLV3 was down‐regulated in the meristem of wox1‐D but accumulated in the other regions, i.e., in the root‐hypocotyl junction and at the sites for lateral root initiation. The fact that the organ size and cell size in leaves of wox1‐D are smaller than those in wild type suggests that cell expansion is possibly affected in order to have partially retarded the development of lateral organs, possibly through alteration of CLV3 expression pattern in the meristem. An S‐adenosylmethionine decarboxylase (SAMDC) protein, SAMDC1, was found able to interact with WOX1 by yeast two‐hybrid and pull‐down assays in vitro. HPLC analysis revealed a significant reduction of polyamine content in wox1‐D. Our results suggest that WOX1 plays an important role in meristem development in Arabidopsis, possibly via regulation of SAMDC activity and polyamine homeostasis, and/or by regulating CLV3 expression. [ABSTRACT FROM AUTHOR]

Abstract: Lead (Pb) is one of the main sources of pollution in the environment, and is severely toxic to plants and animals. Using a DNA microarray, the transcriptional profiles of Arabidopsis thaliana genes in response to Pb treatment were investigated under different concentrations of Pb(NO3)2 solution from low (1μM, 10μM) to high (100μM) during the early stages of toxicity (3h and 24h). At each time point, Pb content was measured to confirm that the extensive heavy metal accumulation in Arabidopsis seedlings was caused by Pb treatment. Furthermore, eighteen selected genes with either moderate or high differential expression values from the microarray analysis were independently analyzed by quantitative real-time RT-PCR to confirm the reliability of the data. In our microarray analysis, the expressions of over 1310 genes were identified in response to Pb treatment. Extensive hierarchical clustering analysis of these responses indicated that the major consistently activated genes were also involved in common stress-induced responses. Especially, those that have been previously reported to be heavy metal inducible genes were significantly induced by lead treatment. Moreover, some important genes encoding enzymes or proteins involved in sulfur assimilation, GSH metabolism, indole-3-acedic acid (IAA) and jasmonic acid (JA) biosynthesis were activated, and these pathways were linked, directly or indirectly through signaling pathways, to biosynthesis of metal transports and detoxification molecules. Taken together, our results provided a new insight into the molecular mechanism of lead detoxification in Arabidopsis, and facilitated an understanding of the general lead/heavy metal-adaptive mechanism undertaken by plants. [Copyright &y& Elsevier]

Arabidopsis AtMRB1 is predicted to encode a novel protein of 432 amino acid residues in length, with four putative trans-membrane domains. In the present study, characterization of AtMRB1 is conducted. Green fluorescent protein (GFP) fusion protein assay showed that AtMRB1 was located in the plasma membrane. Transgenic lines overexpressing AtMRB1 driven by a CaMV 35S promoter were generated. Statistic analysis showed that, during the seedling stage, the organ sizes of the transgenic lines including hypocotyl length, root length and root weight were significantly larger than those of the wild type plants under both light and dark conditions. In the adult plant stage, the AtMRB1 overexpressor plants were found to have larger organ sizes in terms of leaf length and width, and increased number of cauline leaves and branches when bolting. Further observation indicated that the larger leaf size phenotype was due to a larger number of mesophyll cells, the size of which was not altered. Quantitative real-time polymerase chain reaction analysis showed that the transcription of ANT, ROT3 and GRF5 were upregulated in the AtMRB1-overexpressor plants. These data suggest that AtMRB1 is possibly a positive regulator of organ size development in Arabidopsis, mainly through cell number control. [ABSTRACT FROM AUTHOR]

• Auxin is essential for many aspects of plant growth and development, including the determination of lateral organ shapes. • Here, the characterization of a dominant Arabidopsis thaliana mutant spl-D (SPOROCYTELESS dominant), and the roles of SPL in auxin homeostasis and plant development, are reported. • The spl-D mutant displayed a severe up-curling leaf phenotype caused by increased expression of SPOROCYTELESS/NOZZLE (SPL/NZZ), a putative transcription factor gene that was previously linked to sporocyte formation. The spl-D plants also displayed pleiotropic developmental defects including fewer lateral roots, simpler venation patterns, and reduced shoot apical dominance. The leaf and floral phenotypes of spl-D and SPL over-expression lines were reminiscent of yucca (yuc) triple and quadruple mutants, suggesting that SPL may regulate auxin homeostasis. Consistent with this hypothesis, it was found that over-expression of SPL led to down-regulation of the auxin reporter DR5-GUS, and that many auxin-responsive genes were down-regulated in spl-D leaves. Interestingly, the expression of YUC2 and YUC6, two key genes in auxin biosynthesis, was significantly repressed in spl-D plants. • Taken together with the genetic and phenotypic analysis of spl-D/yuc6-D double mutant, these data suggest that SPL may regulate auxin homeostasis by repressing the transcription of YUC2 and YUC6 and participate in lateral organ morphogenesis. [ABSTRACT FROM AUTHOR]

Abstract: CDC5, a Myb-related protein, is reported to be essential for the G2 phase of cell cycle in yeast and animals, but little is known about its function in plants. In this study, Arabidopsis thaliana CDC5 (AtCDC5) is found to be nuclear localized, and the C-terminus of this protein is of transcriptional activation activity in yeast. By taking advantage of the virus induced gene silencing (VIGS) technique, we analyzed the phenotypes of the plants in which AtCDC5 is specifically silenced. The AtCDC5 VIGS plants died before bolting, in which accelerated cell death was detected. Further analysis showed that the transcripts of AtSPT and SAG13, but not SAG12, accumulated in these AtCDC5 VIGS plants, suggesting that the accelerated cell death is different from that occurred during leaf senescence. Furthermore, silencing of AtCDC5 by VIGS in either wild-type, npr1 or nahG plants all induces cell death, suggesting that SA is not crucial for the AtCDC5-associated cell death. [Copyright &y& Elsevier]

Abstract: MYB transcription factors play important roles in many plant developmental processes and various defense responses. Two groups of MYB transcription factors were found to share a W/Y-MDDIW motif. This motif alone shows no trans-activation activity in yeast, however, it enhances the trans-activation activity of the neighbor regions greatly. We further show that all the genes in the group 1, including the previously reported genes AtMYB21, PsMYB26, AmMYB305, and AmMYB340, are predominantly expressed in flowers. Furthermore, we found that these two groups of MYB transcription factor genes might be regulated by light, and probably preferentially expressed in the darkness, suggesting that they may play roles in the light signaling pathway. [Copyright &y& Elsevier]

Rice Bowman-Birk inhibitors (RBBI), with one (8 kD) or two homologous domains (16 kD), were found to be effective trypsin inhibitors in vitro. In this study, we demonstrate that the 25-kD protein corresponding to the three-domain RBBI indeed exists in rice in planta, and that the RBBIs are regulated by development and wounding. We also found by inhibitory activity assay that the 3:13 disulfide bond, but not the 4:5 disulfide bond, suppresses the trypsin-inhibitory activity, and the D3 domain of RBBI3-1 has no inhibitory activity against trypsin, chymotrypsin, paparin or subtilisin. Mutation analyses showed that conversion from Lys to Leu or Tyr in the N-terminal P1 site in D1 domain did not create chymotrypsin-inhibitory activity, suggesting that the structure of the reactive loop in D1 domain hinder the new inhibitory specificity at P1 site, and the chymotrypsin-inhibitory activity might need the participation of other structures, e.g. 3:13 disulfide bond. [ABSTRACT FROM AUTHOR]

Abstract: The cDNA and genomic DNA of a green tissue-specific gene were cloned from maize (Zea mays L.) using cDNA-amplified fragment length polymorphism (cDNA-AFLP) and library screening. The deduced protein was highly similar to Hordeum vulgare germin-like protein 1 (HvGLP1), and the maize gene was therefore designated Zmglp1. Northern blot specifically detected the mRNA of Zmglp1 in young whorl leaves at the early-whorl stage. However, at the late-whorl, tassel, and silk stages, Zmglp1 transcripts were highly abundant in young whorl leaves; less abundant in mature leaves, young tassels, and cobs; and not detectable in roots, immature kernels, and stalks. RNA in situ hybridization revealed that Zmglp1 expressed only in mesophyllous, phloem, and guard cells in the young whorl leaves. Deletion analysis of the promoter in transgenic Arabidopsis resulted in the identification of several regions containing important regulatory cis-elements controlling the expression levels and circadian rhythm-oscillated patterns of Zmglp1. [Copyright &y& Elsevier]

The WIP1-2 gene was cloned from rice. It belongs to the Bowman-Birk inhibitor gene family. Northern blot showed that expression of this gene was induced by wounding and jasmonic acid (JA). It indicates that the OsWIP1 gene plays an important role in the rice defense system. The OsWIP1-2 was cloned into pET28a and expressed in E. coli. Its expressed product was purified in the form of fusion protein and tested for the inhibitory activities against trypsin and chymotrypsin. It was found that the fusion protein could inhibit chymotrypsin, but not trypsin. It was also found that the His tag at its C-terminal affected its inhibitory activity significantly. The fusion protein with a natural C-terminal had the inhibitory activity, while no inhibitory activity was detected in the fusion protein with a (His)6-tag at its C-terminal. This implies that extra amino acid residues at the C-terminal of OsWIP1-2 may interfere with its correct folding. The inhibitory assay indicated that the members of rice Bowman-Birk inhibitor gene family probably differentiated both in their structure and function. [ABSTRACT FROM AUTHOR]

Avian infectious bronchitis virus (AIBV) is classified as a member of the genus coronavirus in the family coronaviridae. The enveloped virus has a positive-sense, single-stranded RNA genome of approximately 28 kilo-bases, which has a 5' cap structure and 3' polyadenylation tract. The complete genome sequence of infectious bronchitis virus (IBV), Beijing isolate, was determined by cloning sequencing and primer walking. The whole genome is 27733 nucleotides in length, has ten open reading frames: 5'-orf1a-orf1ab-s-3a3b-e-m- 6a-6b-n-3'. Alignments of the genome sequence of IBV Beijing isolate with those of two AIBV strains and one SARS coronavirus were performed respectively. The genome sequence of IBV Bering isolate compared with that of the IBV strain LX4 (uncompleted, 19440 bp in size) was 91.2% similarity. However, the full-length genome sequence of IBV Beijing isolate was 85.2% identity to that of IBV Strain Beaudette, and was only 50.8% homology to that of SARS coronavirus. The results showed that the genome of IBV has remarkable variation. And IBV Beijing isolate is not closely related to SARS coronavirus. Phylogenetic analyses based on the whole genome sequence, S protein, M protein and N protein, also showed that AIBV Beijing isolate is lone virus in group III and is distant from SARS coronavirus. In conclusion, this study will contribute to the studies of diagnosis and diseases control on IBV in China. [ABSTRACT FROM AUTHOR]

Focuses on δ-OAT, ornithine-o-aminotransferase, the key enzyme involved in proline biosynthesis. Transfer of the Arabidopsis δ-OAT gene into rice (Oryza satiya L. ssp japonica cv. Zhongzuo 321); Integration confirmed by PCR and Southern blot analysis; Confirmation that the gene was over-expressed in transgenic rice; Biochemical analysis testing in salt or drought stress conditions; Finding that proline contents in the leaves and roots were 5 to 15 times greater than that of non-transgenic control plants; Affect on the germination rate; Slower growth in rice plants with increased NaCl concentration; Enhanced resistance to KCl and MgSO4 stresses found in transgenic rice; Affect of the over-expression of δ-OAT on plant yields; Conclusion that the over-expression of δ-OAT with the accumulation of proline improves salt and drought tolerance and increases of rice yields.

Large collections of insertional Arabidopsis lines are valuable for research on functional genomics. Using the activation tagging vector pSKI015, more than 45 000 T-DNA insertion lines were generated by Agrobacterium-mediated floral-dip transformation protocol. 2304 insertion lines were analyzed and 1502 items of plant sequences flanking the T-DNA insertion sites were obtained by a modified thermal asymmetric interlaced PCR (TAIL-PCR) protocol. These sequences were searched against Genebank database using blast and 1194 insertion sites were determined according to the sequences matching to the Arabidopsis genome sequence. The insertion sites were distributed on all the five Arabidopsis chromosomes and the interfered genes were classified into 14 function categories. Analysis on 1194 items of 100-bp sequences surrounding T-DNA insertion sites showed that 27 and 31% GC contents were likely to favor the T-DNA integration. Sixty-eight items of these 100-bp sequences having more than two insertions were chosen to look for motifs in favor of T-DNA integration. The results showed that “ATNTT” (N represents A/T/C/G) and the polyT and polyA motifs probably play a role in the T-DNA integration event. [Copyright &y& Elsevier]

Bowman-Birk inhibitor (BBI) genes encode serine protease inhibitors that have repetitive cysteine-rich domains with reactive sites for the trypsin or chymotrypsin family. We have identified seven BBI genes from japonica rice (Oryza sativa subsp. japonica var Teqing). All of the genes identified were found in a single cluster on the southern end of the long arm of rice chromosome 1. Four of the seven BBI genes have two repetitive cysteine-rich domains, whereas one has a truncated domain with only one reactive site. We have also identified three novel BBI genes, each of which possesses three repetitive domains instead of two. In situ hybridization analyses indicated that the accumulation of rice BBI transcripts was differentially regulated in germinating embryos and also in the leaves, roots, and flower organs at later developmental stages. Different members of the rice BBI gene family displayed different expression patterns during rice seed germination, and wounding induced the expression of rice BBI transcripts. The three-domain BBIs had higher expression levels than the two-domain BBIs. It was also found that the mRNA of rice BBI genes was present in abundant amounts in scutellar epithelium and aleurone layer cells. RBBI3-1, one of the three-domain RBBI, exhibited in vitro trypsin-inhibiting activity but no chymotrypsin-inhibiting activity. Overexpression of RBBI2-3 in transgenic rice plants resulted in resistance to the fungal pathogen Pyricularia oryzae, indicating that proteinase inhibitors confer resistance against the fungal pathogen in vivo and that they might play a role in the defense system of the rice plant. [ABSTRACT FROM AUTHOR]

Demonstrates that the rga5 is a functional gene encoding gibberellin 20-oxidase in rice. Increase in the endogenous GA[sub 1] level and plant height of rice by over-expressing rga5; Effect of overexpression and antisense-expression on the biological characters of rice.

Provides information on a study which constructed chimeric promoters by fusing wheat GstAl and potato Gst1 gene promoter elements with minimal promoter sequence of rice actin gene Act1 and its 5' untranslated leader sequences. Materials and methods; Results and discussion.

Presents a study which isolated a cloned protein from rice anthers. Materials and methods; Results and discussion.