湖南省某生猪批发市场疫病传播风险评估

为评估湖南省某生猪批发市场猪群疫病的发生风险,找出可能的风险因素,便于提出针对性预防措施,采用自行设计的调查问卷,结合访谈和现场调查,对27户经营户进行了调查,并将调查结果和调运数据相结合进行了疫病传播风险定性评估。结果显示:该市场疫病传入的可能性"高",内部传播的可能性"中等",疫病传出的可能性"高"。生猪调运频次多、数量大,经纪人行为复杂,运输车辆清洗消毒不彻底是可能的风险因素。评估结果提示,应尽量减少经纪人行为影响,重点加强对运输车辆的清洗消毒。     

6种人兽共患病病原核酸液相芯片检测体系的建立

本研究通过设计、合成特异性引物和探针并对其进行修饰,将探针和特定荧光编码微球共价交联后,利用Luminex检测仪读取荧光信号,从而建立了针对布鲁氏菌、沙门氏菌、弓形虫,狂犬病病毒、巴氏通体、弯曲杆菌等6种病原的液相芯片检测方法。数据显示,本研究建立的液相芯片检测体系具有良好的特异性,检测灵敏度达50拷贝数,能同时检测6种重要人兽共患病病原,对于这6种人兽共患病的快速筛查和控制提供了技术支撑。     

2018年安徽省部分地区A型禽流感流行率横断面研究

为了解安徽省A型禽流感病毒感染情况,2018年4—5月,在安徽省北部、中部和南部7个市,随机选取各类型场点173个,在每个场点内随机采集35份咽喉/泄殖腔和环境拭子样品,使用荧光RT-PCR进行A型、H5亚型、H7亚型流感病毒核酸检测。结果显示：在4个养殖场、3个活禽批发市场和17个农贸市场检出了A型禽流感病毒,场点阳性率分别为2.9%（4/140）、75.0%（3/4）、80.9%（17/21）,未检出H5和H7亚型流感病毒核酸;A型禽流感群体流行率为11.2%（95%CI：6.5%~15.8%）,个体流行率为1.2%（95%CI：0.9%~1.5%）;活禽交易市场内,禽群感染A型禽流感病毒的风险较高（OR=136,95%CI：32.7~549.4）。结果表明,A型禽流感病毒在养殖和交易环节存在一定的污染,而在活禽交易市场的污染更严重,是今后禽流感防控的重点,需继续加强活禽交易市场的管理和消毒灭源工作。     

Response of labile organic C and N pools to plastic film removal from semiarid farmland soil

To examine the effects of plastic film removal on grain yield and soil organic matter (SOM), a spring maize (Zea may L.) field experiment was conducted for 5 yr at Changwu Agricultural and Ecological Experimental Station of Northwest China. Compared with traditional plastic film mulching during entire growing stages (FM), plastic film removal at the silking stage (RM) resulted in a 6.3% higher average maize yield. Under the RM treatment, soil organic carbon and total nitrogen significantly increased after the 5‐yr cultivation in the 0‐ to 20‐cm layer. Significant increases in extractable organic C (EOC), KMnO₄‐oxidizable C (KMnO₄‐C) and C management index (CMI) in the 0‐ to 20‐cm layer, and light fraction organic C and EOC in the 20‐ to 40‐cm layer were observed in response to plastic film removal after the 1‐yr treatment; the responses were more significant after 5 yr. Under the RM treatment, significant increases in microbial biomass C, light fraction organic N, extractable organic N, KMnO₄‐C and CMI were also observed after five years in the 20‐ to 40‐cm layer. Moreover, KMnO₄‐C and EOC were much more sensitive than other labile SOM fractions to the application of RM, even after only 1 yr of cultivation. Therefore, compared with mulching for the whole growing season, plastic film removal at the maize silking stage is an effective option for increasing yields and enhancing SOM concentration and soil sustainability in the regions with semiarid monsoon climates that have sufficient rainfall during maize reproductive stages.     

5种农药低空喷雾防治黄脊竹蝗成虫效果分析

为确定低空喷雾无公害药剂防治黄脊竹蝗成虫的林间最佳浓度水平和用药量，掌握低空喷雾施药技术，在福建省三明市三元区的毛竹林建立试验区，应用无人机开展低空喷雾防治试验。结果表明：药后7 d，5种农药的防治效果均超过90%，其林间最佳浓度水平（药剂与纯净水的体积比）为：1.5%苦参碱可溶液和1.2%烟碱·苦参碱乳油均为1：1 000；25%阿维·灭幼脲悬浮剂为1：700，1%苦参·藜芦碱可溶液和4%鱼藤酮乳油均为1：600，原药量用为900 mL/hm²。5种农药防治效果良好，可推广应用于防治黄脊竹蝗成虫。     

2005-2018年澜沧江下游流域景观生态安全时空变化及其驱动因素

[目的] 分析澜沧江下游流域景观生态安全时空变化规律和驱动机制，为该流域及流经国家的人与自然协调可持续发展提供科学依据。[方法] 以2005，2010，2015和2018年4期遥感影像为数据源，通过景观指数和GIS空间分析方法评价流域景观生态安全，采用双变量空间自相关方法明确城市、道路、河流、高程、坡度、气温和降水等因素对景观生态安全的驱动作用。[结果] ①2005—2018年，澜沧江下游流域的整体景观生态安全度呈先升后降的变化特征。其中，北部和中西部景观生态安全较差，东部、南部和东南部较好，但也有恶化趋势；②各景观类型中，景观生态安全度从大到小为：水域 > 林地 > 草地 > 耕地 > 建设用地 > 裸地。其中，林地和草地的景观生态安全度存在波动，耕地和水域的景观生态安全度一直上升，而建设用地和裸地的景观生态安全度持续下降；③距城市距离、距道路距离、气温和降水等社会和气象因素对景观生态安全时空变化的驱动作用最强，距河流距离也对景观生态安全的时空变化有一定解释作用，而高程和坡度等地形因素并非澜沧江下游流域景观生态安全时空变化的主要驱动因素。[结论] 应尽量降低由人类活动引起的生态环境负荷，积极发挥气象因素对生态安全的正向效应，促进澜沧江下游流域的人与自然协调可持续发展。     

Effects of intrauterine growth restriction during late pregnancy on the ovine fetal renal function and antioxidant capacity

This study investigated the effects of intrauterine growth restriction during late pregnancy on the ovine fetal renal function and renal antioxidant capacity. Eighteen ewes pregnant were randomly divided into control group (CG, ad libitum, 0.67 MJ ME·BW^−0.75·day⁻¹, n = 6), restricted group 1 (RG1, 0.18 MJ ME·BW^−0.75·day⁻¹, n = 6), and restricted group 2 (RG2, 0.33 MJ ME·BW^−0.75·day⁻¹, n = 6). At 140 days, the fetal blood, allantoic fluid and kidney tissue were collected to determinate fetal renal function and renal antioxidant capacity. The results showed that the fetal weight, kidney weight, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), aquaporin-2 (AQP-2) and aquaporin-3 (AQP-3), and total antioxidant capacity (T-AOC) in RG1 group were decreased compared with the CG (P < 0.05), but the contents of β2-Microglobulin (β 2-MG), cystatin C (Cys-C), filtered sodium excretion fraction (FENa), malondialdehyde (MDA), and hydroxyl radical (OH) in RG1 group were increased (P < 0.05). The impaired ovine fetal renal growth, antioxidant imbalance and dysfunction of glomerulus ultrafiltration, and the renal tubules reabsorption were induced by maternal malnutrition during late pregnancy.     

辽宁省不同熟期水稻品质性状分析

对辽宁省不同熟期水稻品种品质性状进行综合分析,为水稻优质育种和栽培提供参考。以辽宁省中早熟、中熟、中晚熟和晚熟4个熟期65个品种（系）为试验材料,分析辽宁省不同熟期水稻品种（系）品质性状差异及其相关关系。结果表明,垩白粒率、垩白度、透明度的变异系数较大,不同熟期间表现基本一致。4个熟期中中早熟品种（系）的品质性状整体较好,只有垩白度的优质米达标率较低,说明垩白性状是今后水稻品质改良的重点。相关分析表明,垩白粒率、垩白度均与直链淀粉含量呈极显著正相关,与胶稠度呈显著负相关,糙米率与精米率、整精米率、胶稠度呈极显著正相关。辽宁省水稻优质育种可通过合理调整直链淀粉含量,降低垩白粒率和垩白度,提高整精米率,实现品质的整体改善。     

甘蔗与蔗茅杂交亲本及后代材料的抗旱性鉴定

研究旨在筛选出优良抗旱育种材料,为今后甘蔗抗旱育种和抗旱栽培技术提供重要的理论依据。采用盆栽干旱处理,测定蔗茅野生种无性系、甘蔗栽培品种（系）及其杂交后代共12份材料苗期与抗旱相关的8项生理生化指标,利用极点排序法对供试材料的抗旱性进行了综合评价。结果表明：干旱胁迫下,12份供试材料的Pro、MDA、SS及PMP均呈上升趋势,SP、Chl和SOD活性呈下降趋势,CAT活性有升有降。极点排序法分析表明,12个供试材料的抗旱强弱为：‘蔗茅99-2’>‘蔗茅99-1’>‘蔗茅99-4’>‘蔗茅I91-8’>‘蔗茅99-3’>‘蔗茅90-29’>‘滇蔗01-58’>‘滇蔗04-14’>‘滇蔗02-39’>‘蔗茅II91-2’>‘新台糖10’>‘崖城89-9’,说明蔗茅优质抗旱性状可以通过基因渗透方式传递给后代。在苗期干旱胁迫下,‘蔗茅99-2’在渗透调节等方面表现出积极的生理响应。