非洲猪瘟（African swine fever，ASF）是由非洲猪瘟病毒（African swine fever virus, ASFV）引起的家猪和野猪的一种急性、烈性、高度接触性传染病，发病率和致死率可高达100%，是全球危害猪群最严重的传染病之一，严重威胁

着全球养猪业、食品安全和经济发展。

自2018年8月中国首次爆发ASF疫情至2021年，高毒力基因II型、低毒力基因II型和基因I型三种不同类型的ASFV陆续被报道。这使得ASFV感染的鉴别诊断更具挑战性。截止目前，仍无有效的预防疫苗和特效的治疗药物，因此，能够明确区分基因I型和II型ASFV的鉴别诊断方法对于ASF的有效预防和控制至关重要。在此，我们基于基因I型和II型ASFV编码P72蛋白B646L基因C端的两个单核苷酸多态性（SNP）位点，利用突变阻滞扩增系统（ARMS）和定量实时PCR（qPCR）技术开发了一种双重ARMS-qPCR方法。进一步研究显示，该方法标准曲线的R²值在0.992 - 0.999，线性关系良好；与PRRSV、CSFV、PRV、PCV2、PEDV、TGEV 和 PoRV 七种病原无交叉反应，具有较高的特异性；能够稳定的检测含有10个拷贝数的基因I型和II型ASFV B646L基因的标准品质粒，敏感性较好；组间和组内变异系数均小于2.2%，重复性良好。此外，我们用18个基因I型和18个基因II型ASFV感染样本，包括血液、口腔和直肠拭子、组织和细胞培养物对其进一步的验证，并与动物世界卫生组织（WOAH）推荐的qPCR方法进行比对。结果显示，ARMS-qPCR方法成功鉴别诊断出36个基因I型和II型ASFV感染样本，且与WOAH推荐的qPCR方法检测的结果一致。因此，我们建立的ARMS-qPCR方法可用于检测和区分基因I型和基因II型

Direct-sowing establishment method has great significance in improving winter oilseed rape (Brassica napus L.) production and guaranteeing edible oil security in China. However, nutrient responses on direct sown winter oilseed rape (DOR) performance and population development dynamic are still not well understood. Therefore, five on-farm experiments were conducted in the reaches of the Yangtze River (RYR) to determine the effects of nitrogen (N), phosphorus (P), and potassium (K) deficiencies on population density, dry matter production, nutrient uptake, seed yield, and yield components of DOR plants. Four fertilization treatments included the balanced NPK application treatment (NPK, 180 kg N, 39.3 kg P, 100 kg K, and 1.8 kg borax ha–1) and three nutrient deficiency treatments based on the NPK treatment, i.e., –N, –P, and –K. The results indicated that DOR population density declined gradually throughout the growing season, especially at over-wintering and pod-development stages. Nutrient deficiency decreased nutrient concentration in DOR plants, limited dry matter production and nutrient uptake, and thereby exacerbated density reduction during plants growth. The poor individual growth and reduced population density together decreased seed yield in the nutrient deficiency treatment. Averaged across all the experiments, seed yield reduced 61% by N deficiency, 38.3% by P deficiency, and 14.4% by K deficiency. The negative effects of nutrient deficiency on DOR performances followed the order of –N>–P>–K, and the effects were various among different nutrient deficiencies. Although N deficiency improved DOR emergence, but it seriously limited dry matter production and nutrient uptake, which in turn led to substantial plants death and therefore resulted in a very low harvested density. The P deficiency significantly reduced initial density, limited plants growth, and exacerbated density reduction. The K deficiency mainly decreased individual growth and yield, but did not affect density dynamic. Our results highlighted the importance of balanced NPK application in DOR production, suggesting that management strategy of these nutrients should be comprehensively considered with an aim to build an appropriate population structure with balanced plant density and individual growth.

Overestimation of nitrogen (N) uptake requirement is one of the driving forces of the overuse of N fertilization and the low efficiency of N use in China. In this study, we collected data from 1 844 site-years of rice (Oryza sativa L.) under various rotation cropping systems across the Yangtze River Valley. Selected treatments included without (N0 treatment) and with N application (N treatment) which were recommended by local technicians, with a wide grain range of 1.5–11.9 t ha–1. Across the 1 844 site-years, over 96% of the sites showed yield increase (relative yield>105%) with N fertilization, and the increase rates decreased from 78.9 to 16.2% within the lowest range <4.0 to the highest >6.5 t ha–1. To produce one ton of grain, the rice absorbed approximately 17.8 kg N in the N0 treatment and 20.4 kg N in the N treatment. The value of partial factor productivity by N (PFPN) reached a range of 35.2–51.4 kg grain kg–1 with N application under the current recommended N rate. Averaged recovery rate of N (REN) was above 36.0% in yields below 6.0 t ha–1 and lower than 31.7% in those above 6.0 t ha–1. Soil properties only affected yield increments within low rice yield levels (<5.5 t ha–1). There is a poor relationship between N application rates and indigenous nitrogen supply (INS). From these observations and considering the local INS, we concluded there was a great potential for improvement in regional grain yield and N efficiency.

To characterize the β-lactam resistance in veterinary clinical isolates of Haemophilus parasuis, 115 isolates were examined for the β-lactam resistance, the possession of β-lactamase, and the presence of β-lactamase genes. The genetic relationship among isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Overall, the commonly detected resistance phenotypes were resistant to ampicillin (26.09%), penicillin (22.61%), amoxicillin (21.74%), cefazolin (14.78%), cefaclor (12.17%), and cefotaxime (6.96%). These strains showed high minimal inhibitory concentration (MICs) to oxacillin. 20.87% strains produced β-lactamase, and 4.35% strains showed extended-spectrum b-lactamase (ESBL) phenotype. Moreover, 19 strains harboured bla genes including TEM-1 (n=5), TEM-116 (n=10), and ROB-1 (n=5). Significantly, one strain possessed both TEM-1 and ROB-1, and displayed resistance to cefotaxime (MIC=8 mg L-1). The epidemiological analysis of PFGE revealed high genetic diversity among bla-positive isolates. This work shows that TEM- and ROB-type β-lactamases are prevalent in H. parasuis isolates in China.