Monoclonal antibodies (mAbs) are widely used in virus research and disease diagnosis.  The nucleoprotein (NP) of influenza A virus (IAV) plays important roles in multiple stages of the virus life cycle.  Therefore, generating conserved mAbs against NP and characterizing their properties will provide useful tools for IAV research.  In this study, two mAbs against the NP protein, 10E9 and 3F3, were generated with recombinant truncated NP proteins (NP-1 and NP-2) as immunogens.  The heavy-chain subclass of both 10E9 and 3F3 was determined to be IgG2α, and the light-chain type was κ.  Truncation and site-specific mutation analyses showed that the epitopes of mAbs 10E9 and 3F3 were located in the N terminal 84–89 amino acids and the C terminal 320–324 amino acids of the NP protein, respectively.  We found that mAbs 10E9 and 3F3 reacted well with the NP protein of H1–H15 subtypes of IAV.  Both 10E9 and 3F3 can be used in immunoprecipitation assay, and 10E9 was also successfully applied in confocal microscopy.  Furthermore, we found that the 10E9-recognized ₈₄SAGKDP₈₉ epitope and 3F3-recognized ₃₂₀ENPAH₃₂₄ epitope were highly conserved in NP among all avian and human IAVs.  Thus, the two mAbs we developed could be used as powerful tools in the development of diagnostic methods of IAV, and also surely promote the basic research in understanding the replication mechanisms of IAV.

在中国南方稻作区，传统的早稻-晚稻双季稻模式（DR）种植面积迅速减少，同时，再生稻（RR）和稻虾（RC）作为两种新兴稻作模式正快速发展。本文采用能值分析法和生命周期评价法评估了稻作模式转变对水稻生产经营经济效益和生态可持续性的影响。经济效益分析结果表明：RC的生产产值和利润远大于RR和DR，RR和RC比DR的产投比分别提高了25.5和122.7%。与DR相比，由于较高的灌溉水、电力、幼虾苗和饲料等生产资料的投入，RC增加了能值投入，而RR则具有较低的总能值和不可再生能值投入，如灌溉水、电力、肥料和农药等。当稻作模式从DR转变为RR或者RC时，水稻生产的环境负载率分别减少了20.4和38.2%，而能值可持续性指标增加了34.8和65.2%。生命周期评价结果表明：RR和RC具有较低的潜在环境影响，它们的综合环境影响指数比DR分别低35.0和61.0%。与DR相比，RR的稻谷产量没有明显下降，但显著减少了经济成本和能值投入，而RC模式下稻谷产量下降严重（与RR相比减少了53.6%）。综上，再生稻模式是一种更有利于全面实现粮食安全、经济效益和生态可持续的种植模式。

水稻种植区域广以及播种期不一等原因引起的生长季温度不适宜，导致了水稻产量和品质的降低。本研究目的是评估不同物候期温度对水稻产量及品质的影响，以获得长江流域水稻不同物候期适宜温度范围。因此，本研究以区域性品种为研究对象，在长江流域不同生态区开展播期试验,观测比较水稻生育进程、产量和品质的差异。结果表明不同播期以及不同生态区，水稻生育进程、产量和品质具有显著性差异，而这恰好与营养生长期（VT）及前20天灌浆期日平均温度（GT20）显著相关。此外，与VT和GT20相比，水稻幼穗分化期温度（RT）变化差异相对较小。因此，根据不同产量和品质的VT和GT20阈值，将本研究试验结果划分为4种情景（Ⅰ, Ⅱ, Ⅲ, 和 Ⅳ）。其中，情景Ⅰ可获得高的整精米产量和稻米品质；与情景Ⅰ相比，情景Ⅲ和 Ⅳ的整精米产量下降了30.1%和27.6%；情景Ⅱ整精米产量增加不显著，但是其垩白粒率和垩白度要比情景Ⅰ分别高出50.6%和56.3%。综上所述，情景Ⅰ下的VT和GT20组合方式（22.8℃<VT<23.9℃和24.2℃<GT20<27.0℃或3.9℃<VT<25.3℃和4.2℃<GT20<24.9℃），可用于指导长江流域水稻播期调整和水稻适宜品种的选取，以提高该区域的水稻产量和品质。

【目的】H7亚型禽流感病毒(Avian influenza virus, AIV)和H5亚型一样，多数属于高致病性毒株，通常在禽类间传播，引起家禽出现严重的临床症状和高死亡率。从1996年至2012年，加拿大、意大利、墨西哥、荷兰、英国和美国出现了人感染H7亚型流感病毒(H7N2、H7N3和H7N7)的病例。2013年，中国报告了人感染H7N9流感病毒的事件，此后，该病毒持续在人和禽类中传播。因此，开展H7亚型禽流感病毒抗体检测工作成为一个重要问题。【方法】该研究用纯化的H7-AIV作为包被抗原，辣根过氧化物酶（Horseradish peroxidase, HRP）标记的单克隆抗体1H9（HRP-1H9）作为竞争抗体，采用棋盘滴定法建立了一种检测H7亚型AIV抗体的竞争性酶联免疫吸附实验(Competitive enzyme-linked immunosorbent assay, cELISA)。【结果】抗原包被的最佳浓度为5 μg mL^-1，血清稀释度为1/10，酶标抗体为1/3000。用ROC曲线分析法测定178份AIV阴性和368份AIV阳性血清（n=546）的cELISA临界值，当PI为40%时，cELISA的特异性和敏感性分别为99.15%和98.12%。该方法可检测H7Nx（N1--N4、N7--N9）禽流感病毒抗体，与H1 -- H6、H8 -- H15亚型禽流感病毒及鸡新城疫病毒(Newcastle disease virus, NDV)、传染性支气管炎病毒(Infectious bronchitis virus, IBV)和传染性法氏囊病病毒(Infectious bursal disease virus, IBDV)等常见禽类病毒无反应，具有良好的特异性。该方法与血凝素抑制试验的符合率为98.56%。重复性实验表明，批内和批间重复的变异系数均小于12%。【结论、创新性】综上所述，本研究利用H7亚型特异性酶标单克隆抗体作为竞争抗体，建立了cELISA抗体检测方法，其优势是酶标抗体与待检血清同时加入反应孔中进行竞争反应，与先加入待检血清，再加竞争抗体反应的常规方法比较，简化了操作步骤，缩短反应时间，为开展H7-AIV抗体的大量检测提供了一种简单、便捷的技术手段。

Inoculation of wheat (Triticum aestivum L.) leaves with wheat powdery mildew fungus (Blumeria graminis f. sp. tritici) induces the cell death in adventitious roots.  Reactive oxygen species (ROS) play a key role in respond to biotic stress in plants.  To study the involvement of ROS and the degree of cell death in the wheat roots following inoculation, ROS levels and microstructure of root cells were analyzed in two wheat cultivars that are susceptible (Huamai 8) and resistant
(Shenmai 8) to powdery mildew fungus.  At 18 d after powdery mildew fungus inoculation, only Huamai 8 displayed the leaf lesions, while root cell death occurred in both varieties.  Huamai 8 had a high level of ROS accumulation, which is associated with increased root cell degradation, while in Shenmai 8, there was little ROS accumulation correlating with slight root cell degradation.  The molecular study about the expression levels of ROS scavenging genes (MnSOD and CAT) in wheat roots showed that these genes expression decreased after the leaves of wheat was inoculated.  The difference between Huamai 8
and Shenmai 8 on subcellular localization of H₂O₂ and O₂^–· was corresponded with the different down-regulation of the genes encoding for superoxide dismutase and catalase in two wheat cultivars.  These results suggested that ROS were involved in the process by which powdery mildew fungus induced cell death in wheat roots.

   In 2013, a human influenza outbreak caused by a novel H7N9 virus occurred in China.  Recently, the H7N9 virus acquired multiple basic amino acids at its hemagglutinin (HA) cleavage site, leading to the emergence of a highly pathogenic virus.  The development of an effective diagnostic method is imperative for the prevention and control of highly pathogenic H7N9 influenza.  Here, we designed and synthesized three pairs of primers based on the nucleotide sequence at the HA cleavage site of the newly emerged highly pathogenic H7N9 influenza virus.  One of the primer pairs and the corresponding probe displayed a high level of amplification efficiency on which a real-time RT-PCR method was established.  Amplification using this method resulted in a fluorescent signal for only the highly pathogenic H7N9 virus, and not for any of the H1–H15 subtype reference strains, thus demonstrating high specificity.  The method detected as low as 39.1 copies of HA-positive plasmid and exhibited similar sensitivity to the virus isolation method using embryonated chicken eggs.  Importantly, the real-time RT-PCR method exhibited 100% consistency with the virus isolation method in the diagnosis of field samples.  Collectively, our data demonstrate that this real-time RT-PCR assay is a rapid, sensitive and specific method, and the application will greatly aid the surveillance, prevention, and control of highly pathogenic H7N9 influenza viruses.

    Plant height (PH) is one of the most important agronomic traits of rice, as it directly affects the lodging resistance and the high yield potential. Meanwhile, PH is often constrained by water supply over the entire growth period. In this study, a recombinant inbred line (RIL) derived from Xiaobaijingzi and Kongyu 131 strains grown under drought stress and with normal irrigation over 2 yr (2013 and 2014), respectively (regarded as four environments), was used to dissect the genetic basis of PH by developmental dynamics QTL analysis combined with QTL×environment interactions. QTLs with net effects excluding the accumulated effects were detected to explore the relationship between gene×gene interactions and gene×environment interactions in specific growth period. A total of 26 additive QTLs (A-QTLs) and 37 epistatic QTLs (E-QTLs) associated with PH were detected by unconditional and conditional mapping over seven growth periods. qPH-2-3, qPH-4-3, qPH-6-1, qPH-7-1, and qPH-12-5 could be detected by both unconditional and conditional analyses. qPH-4-3 and qPH-7-5 were detected in four stages (periods) to be sequentially expressed QTLs controlling PH continuous variation. QTLs with additive effects (A-QTLs) were mostly expressed in the period S3|S2 (the time interval from stages 2 to 3), and QTL×environment interactions performed actively in the first three stages (periods) which could be an important developmental period for rice to undergo external morphogenesis during drought stress. Several QTLs showed high adaptability for drought stress and many QTLs were closely related to the environments such as qPH-3-5, qPH-2-2 and qPH-6-1. 72.5% of the QTLs with a and aa effects detected by conditional analysis were under drought stress, and the PVE of QTLs detected by conditional analysis under drought stress were also much higher than that under normal irrigation. We infer that environments would influence the detection results and sequential expression of genes was highly influenced by environments as well. Many QTLs (qPH-1-2, qPH-3-5, qPH-4-1, qPH-2-3) coincident with previously identified drought resistance genes. The result of this study is helpful to elucidating the genetic mechanism and regulatory network underlying the development of PH in rice and providing references to marker assisted selection.

Segregation analysis of the mixed genetic model of major gene plus polygene was used to identify the major genes for cotton yield-related traits using six generations P1, P2, F1, B1, B2, and F2 generated from the cross of Baimian 1 × TM-1. In addition to boll size and seed index, the major genes for the other five traits were detected: one each for seed yield, lint percentage, boll number, lint index; and two for lint yield. Quantitative trait locus/loci (QTL) mapping was performed in the F2 and F2:3 populations of above cross through molecular marker technology, and a total of 50 QTL (26 suggestive and 24 significant) for yield-related traits were detected. Four common QTL were discovered: qLP-3b(F2)/qLP-3(F2:3) and qLP-19b (F2)/qLP-19(F2:3) for lint percentage, qBN-17(F2)/qBN-17(F2:3) for boll number, and qBS-26b(F2)/qBS-26(F2:3) for boll size. Especially, qLP- 3b(F2)/qLP-3(F2:3), not only had LOD scores >3 but also exceeded the permutation threshold (5.13 and 5.29, respectively), correspondingly explaining 23.47 and 29.55% of phenotypic variation. This QTL should be considered preferentially in marker assisted selection (MAS). Segregation analysis and QTL mapping could mutually complement and verify, which provides a theoretical basis for genetic improvement of cotton yield-related traits by using major genes (QTL).

Water used in agriculture consumes much energy, mainly due to pumping water for irrigation, but the water-energy nexus is always neglected in arid and semi-arid areas. Based on hydrological observation data, irrigation data and socioeconomic data over the past 50 yr, this study has derived a detailed estimate of greenhouse gas (GHG) emissions from agricultural water use in the Minqin Oasis. Results show that the decreasing water supply and increasing demand for agriculture has caused severe water deficits over the past 50 yr in this region. The groundwater energy use rate rose by 76% between 1961 and 2009 because of the serious decline in groundwater levels. An increase in pump lift by an average 1 m would cause GHG emission rates to rise by around 2%. Over the past 10 yr, the GHG emissions from groundwater accounted for 65-88% of the total emissions from agricultural water. GHG emissions for diverted water varied from 0.047 to 0.074 Mt CO2e as the water input increased. Long distance conveyance and high pump lifts need more electricity input than groundwater abstraction does. Government policies have had a favorable effect on total emissions by reducing water abstraction. But groundwater depletion, exacerbated by a growing population and an expansion in arable land, remains the principal energy-water nexus challenge in the region. In response to the increasing water-energy crisis, energy-saving irrigation technology, matching to cost efficiencies, and better coordination between different infrastructural agencies could be feasible ways of rendering the water and energy sectors more sustainable over the long term.

Basic vegetative period (BVP) is an important trait for determining flowering time and adaptation to variable environments. A short BVP barley mutant is about 30 d shorter than its wild type. Genetic analysis using 557 F2 individuals revealed that the short BVP is governed by a single recessive gene (BVP-1) and was further validated in 2 090 F3 individuals. The BVP-1 gene was first mapped to barley chromosome 1H using SSR markers. Comparative genomic analysis demonstrated that the chromosome region of BVP-1 is syntenic to rice chromosome 5 and Brachypodium chromosome 2. Barley ESTs/genes were identified after comparison with candidate genes in rice and Brachypodium; seven new gene-specific markers were developed and mapped in the mapping populations. The BVP-1 gene co-segregated with the Mot1 and Ftsh4 genes and was flanked by the gene-specific markers AK252360 (0.2 cM) and CA608558 (0.5 cM). Further analysis demonstrated that barley and wheat share the same short BVP gene controlling early flowering.

The joint analysis of the mixed genetic model of major gene and polygene was conducted to study the inheritance of cryotolerance in cotton during the overwintering period. H077 (G. hirsutum L., weak cryotolerance) and H113 (G. barbadence L., strong cryotolerance) were used as parents. Cryotolerance of six generation populations including P1, P2, F1, B1, B2, and F2, from each of the two reciprocal crosses H077×H113 and H113×H077 were all investigated. The results showed that cryotolerance in cotton during the overwintering period was accorded with two additive major genes and additivedominance polygene genetic model. For cross H077×H113, the heritabilities of major genes in B1, B2, and F2 were 83.62, 76.84, and 90.56%, respectively; and the heritability of polygene could only be detected in B2, which was 7.76%. For cross H113×H077, the heritabilities of major genes in B1, B2, and F2 were 67.42, 68.95, and 83.40%, respectively; and the heritability of polygene was only detected in F2, which was 6.51%. In addition, the whole heritability in F2 was always higher than that in B1 and B2 in each cross. Therefore, for the cryotolerance breeding of perennial cotton, the method of single cross recombination or single backcross should be adopted to transfer major genes, and the selection in F2 would be more efficient than that in other generations.

To develop a modified live vaccine (MLV) against porcine reproductive and respiratory syndrome virus (PRRSV), virulent CH-1a strain was attenuated by serial passages up to 130 passage (P130) in Marc-145 cells. The virulence and immune efficacy of the attenuated CH-1a were evaluated in pigs. The results showed that animals inoculated with P130 did not develop any clinical sign of the disease, but produced rapid and effective humoral immune responses against PRRSV challenge, indicating that attenuated CH-1a P130 is the candidate as the effective vaccine against PRRSV. To define the potential mutations in the attenuated CH-1a genome, we sequenced and analyzed the ORF5 gene of CH-1a strain of different passages (P39, P55, P65, P70, P85, P100, P115, P120, P125, and P130) and found that three mutations (C5Y, H38Q and L146Q) which may be related with the attenuation of CH-1a. In addition, we also found a unique restriction enzyme site (TspEI) in the ORF5 gene of attenuated CH-1a, which can be used as a genetic marker to distinguish original and attenuated CH-1a.