硝酸还原酶（Nitrate reductase, NR）是植物体内同化硝态氮的关键酶，其活性受翻译后磷酸化修饰调控。通过分析硝酸还原酶NIA1磷酸化位点定向突变株系（S532D和S532A）、OsNia1过表达株系（OE）及野生型（WT）的表型、氮代谢和活性氧代谢的差异，探究不同形态氮素营养下NIA1蛋白的去磷酸化对水稻生长和生理生化的影响。研究表明，与WT和OE相比，S532D和S532A具有更强的氮素同化能力。以硝酸铵作为氮源时，S532D和S532A的株高、地上部干重和叶绿素含量均低于WT和OE，H₂O₂、MDA和亚硝酸盐含量则较高；以硝酸钾作为氮源时，S532D和S532A的株高、地上部干重和叶绿素含量高于WT和OE，所有株系叶片中的H₂O₂和MDA含量无明显差异，各株系间亚硝酸盐含量差异减小；以硫酸铵作为氮源，除NR活性外，各株系间的其它生理指标均无显著差异。相较于硝酸铵和硫酸铵，以硝酸钾作为氮源时各株系叶片中NH₄⁺-N的含量较低。q-PCR分析表明OsGS和OsNGS1基因表达受下游代谢产物的负调控，OsNrt2.2受硝酸盐诱导表达。综上，硝酸铵作为氮源时NIA1磷酸化位点定向突变株系长势较弱是由于过量积累的亚硝酸盐对自身的毒害；硝酸钾作为氮源时NIA1磷酸化位点定向突变株系对硝酸盐、亚硝酸盐和铵盐的同化速率加快，能够提供较多的氮素营养，提高了水稻对铵态氮缺乏的耐受性。

遗传特性的探索，可以了解群体内遗传结构，对探索群体形成提供有效信息。而选择信号检测不仅能反映选择对品种的培育作用，还有助于更好地理解选择机制。海南猪、五指山猪、两广小花猪是我国华南地区优秀的地方品种，具有耐粗饲、性成熟早、肉质鲜美等优点。杜洛克猪经历了长时间的正向选择，具有生长速度快、饲料转换率高、瘦肉率高等特点。本研究基于SNP（single-nucleotide polymorphism）芯片数据，对华南地区地方猪种及杜洛克猪6个群体，共计259个个体进行了主成分分析、系统发生树构建、群体结构分析、连锁不平衡分析、有效群体大小估计以及全基因组选择信号检测，旨在探究华南地区地方猪种的遗传特性与选择信号，为后续保种及利用提供一定参考信息。结果显示，6个猪群体被分为华南地区地方猪种和杜洛克猪两簇，而华南地区地方猪种簇中，海南地区地方猪种与两广小花猪分为两簇，此结果与主成分分析结果相似；5个华南地区地方猪种的有效群体大小在近年呈现迅速衰减趋势；当标记间距为100kb时，5个地方猪群体的连锁不平衡程度变化范围为：0.16-0.20，而杜洛克猪群体的连锁不平衡程度为0.32；此外，在华南地区地方猪种群体基因组中共检测到15个潜在受选择区域，在杜洛克猪基因组中检测到8个潜在受选择区域。综上所述，华南地区地方猪保种工作刻不容缓。群体结果分析和选择信号检测揭示了华南地区地方猪种不同群体间受选择方向的差异。本研究不仅为研究华南地区地方猪种的起源、有效群体大小和选择提供了新见解，并且还为日后该猪种的利用提供了参考信息。

重组病毒活载体疫苗是一种能够有效激活特异性和非特异性免疫、可多联多价、安全性好的新型疫苗。动物α疱疹病毒拥有较大的基因组，含有多个不影响病毒复制的非必需区，能够插入接受外源基因并表达相应抗原蛋白；同时具有较广泛的宿主谱，能够在宿主体内复制并持续刺激动物产生对抗相应病原的免疫力，是作为重组病毒活载体疫苗的理想载体。随着基因编辑技术的发展，可通过多种方法构建能够表达外源基因的重组病毒。目前以动物α疱疹病毒为载体的重组病毒活载体疫苗研究已经涉及禽类、猪、牛、羊、伴侣动物等，目前成功构建的多株重组动物α疱疹病毒能免疫后可使动物同时获得对多种疾病的免疫。本文总结了重组动物α疱疹病毒构建方法、外源基因的引入和表达以及动物α疱疹病毒活载体疫苗免疫作用三个方面的内容，包括了最新的基因编辑技术、不同的构建策略及其优缺点、外源基因的选择、插入形式和位点等，并介绍了各种动物α疱疹病毒活载体疫苗的最新研究进展，旨在为新型动物α疱疹病毒活载体疫苗的研究和开发提供一定的参考。

Bleeding canker, a devastating disease of pear trees (Pyrus pyrifolia L.), was first reported in the 1970s in Jiangsu, China and more recently in other provinces in China.  Trees infected with bleeding canker pathogen, Dickeya fangzhongdai, develop cankers on the trunks and branches, and a rust-colored mixture of bacterial ooze and tree sap could be seen all over the trunks and branches.  In this study, we provided detail descriptions of the symptoms and epidemiology of bleeding canker disease.  Based on pathogenic and phenotypic characterizations, we identified the causal agent of bleeding canker of pear as D. fangzhongdai.  Dickeya fangzhongdai strains isolated from pear were also pathogenic on Solanum tuberosum, Brassica pekinensis, Lycopersicon esculentum, and Phalaenopsis aphrodite based on artificial inoculation, and the pathogen were more virulent on potato than that of D. solani strain.  This study provides new information about this disease and bleeding canker disease of pear.

The aim of this study was to evaluate the growth of rape (Brassica napus L.) seedlings under different light intensities to select appropriate conditions for cultivation in an indoor system.  Seedlings were grown under different light intensities of red and blue light provided by light-emitting diodes (LEDs) and their self-adjustment ability and changes in leaf microstructure were evaluated.  Light was supplied by red LEDs with peak wavelengths of 630 (R₁) and 660 nm (R₂) and by blue LEDs (B) with a peak wavelength of 445 nm (the light intensity ratio of R₁:R₂:B was 3:3:2), at intensities of 400 (R₁R₂B400), 300 (R₁R₂B300), and 200 μmol m^–2 s^–1 (R₁R₂B200).  Natural solar light served as the control (C).  Plant height, stem diameter, root length, leaf area, and dry weight of rape seedlings gradually increased with increasing light intensity.  The seedlings in the R₁R₂B400 treatment grew more vigorously, while those in the R₁R₂B200 treatment were weaker.  The photosynthetic pigment contents did not differ significantly between the R₁R₂B400 treatment and C, but were significantly lower in the R₁R₂B300 and R₁R₂B200 treatments.  The highest intercellular CO₂ concentration, stomatal conductance, and transpiration rate were in the R₁R₂B300 treatment.  The highest photosynthetic rate was in the R₁R₂B400 treatment, and was related to more compact leaves, thicker and tidier palisade and spongy tissues, and well-developed chloroplasts.  In contrast, the seedlings in the R₁R₂B200 treatment had disordered mesophyll cells, round chloroplasts, and fractured and fuzzy grana lamellae, all of which inhibited plant growth.  In conclusion, the seedlings in the R₁R₂B400 treatment had well-developed leaves, which favored photosynthesis.  Compared with the light intensities below 300 μmol m^–2 s^–1, the light intensity of 400 μmol m^–2 s^–1 provided by a combination of red and blue LEDs was beneficial for cultivating strong and healthy rape seedlings in an artificial system.  

Using a household survey data collected from four leading maize producing provinces in China, this paper studies the decisions of maize farmers on seed choices and variety portfolios when asymmetrical information exists in the market. Our findings indicate, while farmers generally tend to adopt new varieties with the expectation of potential higher yield, the primary driver to do so for those who have less information on seed varieties is to reduce production risk. Improving seed market management and providing more seed information to farmers would be beneficial in choosing seed varieties and maize production.

To gain more precise information about molecular genetic variation for wild populations of Blumeria graminis f. sp. tritici from Qinghai Province, China, 38 single-colony isolates were purified from samples collected from Haidong District, Xining City and Hainan Tibetan Autonomous Prefecture in 2010. The virulence of 21 isolates among them was tested at seedling stage on 34 wheat cultivars (lines) carrying known powdery mildew (Pm) resistant genes. The results showed that V1a, V3a, V3c, V3e, V5a, V6, V7, V8 and V19 had high virulence frequencies (>75%), indicating a wide distribution; and V1c, V5b, V12, V13, V16, V21, VXBD, V2+6, V2+Mld and V4+8, with less distribution, appeared to be lower in frequencies (0-20%). The Nei’s gene diversity (H), Shannon’s information index (I) and the percentage of polymorphic loci (P) were 0.23, 0.35 and 67.65%, respectively, which revealed a virulent diversity. The results from single nucleotide polymorphisms (SNPs) of 38 isolates showed that three housekeeping genes were found to contain a total of 9 SNP sites. 10 haplotypes (H1-H10) were inferred from the concatenated sequences, with 1 haplotype (H1) comprising of over 55% of Qinghai population. Phylogenic analysis did not show obvious geographical subdivision between the isolates. A multilocus haplotype network presented a radial structure, with H1 in the central as an inferred ancestor. Using analysis of molecular variance (AMOVA), we found 1.63% of the total variation was among populations and 98.37% within populations, with a low fixations index (FST=0.01634, P<0.05). This revealed a relatively high genetic diversity but a low genetic divergence in Qinghai population. Moreover, the molecular data on gene flow (Nm=6.32) confirmed the migration of pathogen populations among areas in Qinghai Province.