首创直接利用野生稻杂交选育恢复系与应用

袁隆平先生利用野生稻的败育型细胞质基因育成不育系,而笔者则首创了直接利用野生稻细胞核基因选育恢复系的新途径。笔者介绍了直接利用野生稻杂交选育恢复系的技术路线及方法,该法利用野生稻作为主体亲本,与多个各具有显著特点的恢复材料杂交,充分利用野生稻抗性强、适应性广、米质优等特点。采用“大群体多世代”的育种方法成功育成强优广谱性恢复系测253,并育成一系列高产、优质、多抗的新组合。笔者还介绍了测253及其配组组合的应用和产生的社会效益。     

CZDM膜制氮机组降氧工艺与氧气浓度变化规律研究

对CZDM膜制氮机组降氧工艺与氧气浓度变化规律进行了研究,利用CZDM膜制氮机纽产生的低氧浓度气体,采用一系列降氧工艺使试验仓粮堆内的氧气浓度从20.9%降低到2.0%共用去408 h.各工艺阶段粮堆平均氮气(氧气)浓度变化与该工艺前粮堆平均氮气(氧气)浓度和该工艺充入粮堆氮气浓度差成正比.本研究结果为开展低氧防治储粮害虫技术的应用提供了参考依据.     

Variations in clinical presentation and anatomical distribution of gross lesions of African swine fever in domestic pigs in the southern highlands of Tanzania: a field experience

African swine fever is a contagious viral disease responsible for up to 100% mortality among domestic pigs. A longitudinal study was carried out to determine the clinical presentation and anatomical distribution of gross lesions in affected pigs in Mbeya region, Tanzania during the 2010 to 2014 outbreaks. Data were collected during clinical and postmortem examination by field veterinarians and using a structured questionnaire. A total of 118 respondents (100%) showed awareness about African swine fever. During previous outbreaks, the mortality rate was almost 100%, while in 2014 it was estimated to be less than 50%.The clinical picture of the 2010–2012 outbreaks was characterized by high fever, depression, inappetance, mucosal congestion, hemorrhages, erythematous lesions in different body parts, and abortion. Several internal organs including the kidneys, spleen, and liver were congested and edematous. During the 2014 outbreak, a number of pigs (49.7%) were asymptomatic when brought to slaughter slabs but were found to have African swine fever gross lesions at postmortem examination as compared to 12.3% in 2010–2012. Bluish discoloration, which is normally distributed on the non-hairy parts of the body, was not apparent in some pigs except at postmortem examination. Some pigs (36.1%) presented nasal and/or oral bloody discharges which were uncommon (9.1%) during previous outbreaks. Moreover, other gross features included enlarged dark red renal lymph nodes and spleen. Clinical signs such as anorexia, diarrhea, and pyrexia were mainly observed when affected pigs reached moribund stage. The majority of pregnant sows died without presenting abortions. In some litters, suckling piglets (3–6 weeks) survived from the disease. These findings indicated that in 2014, African swine fever outbreak in Mbeya region was characterized by a different clinical picture.     

加速碳酸化法稳固化工业危险废物焚烧飞灰重金属的研究

该文对某危险废物处置中心工业危险废物焚烧产生飞灰的加速碳酸化过程进行了研究。测定飞灰中Cr、Ni、Cu、Zn、Cd、Hg、Pb等重金属浸出浓度,其中Pb浸出浓度超过危险废物鉴别标准及填埋场入场控制标准限值,高达288.40mg/L。对飞灰进行碳酸化处理,探讨碳酸化反应时间、反应温度、液固比和CO_2浓度等因素对飞灰中重金属Pb浸出特性的影响。结果表明,在反应时间2~4h,反应温度10~50℃、液固比3∶1~5∶1,CO_2浓度60%~100%范围内碳酸化效果显著。并通过正交实验得到最优反应条件为CO_2浓度100%,反应时间3h,液固比4∶1,反应温度30℃。通过利用X射线衍射(XRD),扫描电镜(SEM)对飞灰碳酸化前后进行表征。结果表明,碳酸化后飞灰中Ca(OH)2、CaClOH消失,CaCO_3增加明显,晶体吸附使得重金属浸出明显下降,飞灰颗粒表面生成了以CaCO_3为主的片状和圆柱状的晶体物质。重金属浸出实验表明,飞灰经碳酸化处理后,重金属Pb浸出浓度由288.40mg/L降至0.02mg/L。碳酸化法处理工业危险焚烧产生飞灰可以有效控制重金属Pb的浸出以及降低体系的pH(由13~14降至7左右),同时实现对温室气体CO_2的固定,具有潜在的应用价值。     

Marker-Assisted Selection of Xa21 Conferring Resistance to Bacterial Leaf Blight in indica Rice Cultivar LT2

Bacterial leaf blight of rice (BLB), caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient parent. IRBB21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC₃F₃ lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC₃F₃ 5.1.5.1, BC₃F₃ 5.1.5.12, BC₃F₃ 8.5.6.44, BC₃F₃ 9.5.4.1 and BC₃F₃ 9.5.4.23) were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.     

基于系统动力学的稻田塘堰系统水转化模拟及验证

为了描述稻田塘堰系统水转化过程,以水量平衡原理为基础,建立稻田塘堰系统水转化系统动力学模型。利用漳河灌区三干渠中游区域尺度塘堰日水位观测资料对模型进行检验,模拟结果的复相关系数、Nash-Sutcliffe系数和均方根误差分别为0.90、0.79和0.155 m/d。在浅水灌溉模式下,对研究区域内塘堰调蓄方式进行动态模拟,结果表明,塘堰在完全调蓄时可以保障作物充分灌溉,在部分调蓄与不调蓄时作物分别在第72天和45天发生水分胁迫,塘堰灌溉对保证作物正常生长天数具有显著效果。当塘堰完全调蓄时,在浅水灌溉、湿润灌溉及间歇灌溉模式下,塘堰最低蓄水量占最大蓄水量的比例分别为2.0%、18.9%和41.3%,塘堰的有效水利用率分别为84.7%、80.9%和67.7%。研究可为稻田塘堰系统合理利用雨水资源、灌溉管理提供理论依据。     

毒性与无毒性织纹螺肌肉蛋白的差异分析

通过SDS-PAGE分析毒性和无毒性织纹螺肌肉蛋白的电泳图谱差异,综合比较蛋白条带的迁移率及浓度得出,毒性织纹螺肌浆蛋白的特征条带主要为23.6ku和35.0ku,无毒性织纹螺的特征条带主要为22.8ku和31.2ku;毒性织纹螺肌原纤维的特征条带主要为38.0ku、50.8ku和135.0ku,无毒性织纹螺的特征条带主要为36.9ku和125.8ku.结合优化样品制备、等电点聚焦程序等条件,初步建立了织纹螺肌肉蛋白的双向电泳条件,并通过双向电泳分析了毒性和无毒性织纹螺肌肉中存在的差异蛋白.     

国内外杀虫绿僵菌制剂的登记现状与剂型技术进展

生物农药在植物保护工作中日益受到重视。绿僵菌是重要的昆虫病原真菌,作为真菌杀虫剂已被成功应用于蝗虫、金龟子、象甲等多种害虫的田间防治。近40年来,已有83个绿僵菌产品在13个国家或地区获得注册,制剂研究与加工技术方面取得了新进展,可湿性粉剂、悬浮剂等传统剂型质量得到改善,超低容量剂、浸渍剂等新剂型可适应特殊应用环境,产品的防治对象涵盖范围更广。本文就国内外绿僵菌产品注册登记情况、制剂类型特性及制剂技术的载体、助剂和加工过程等主要因素进行综述,以期为我国真菌生物农药的科研、应用及产业发展提供基础依据。     

狂犬病诊断技术研究进展

狂犬病是由狂犬病毒引起的以中枢神经系统感染为特征的一种人兽共患病。除常规的临床诊断外,狂犬病的确诊依赖于实验室诊断方法,方法主要有病原学诊断、血清学诊断和分子生物学诊断方法等。该文就目前国内外应用的狂犬病诊断方法进行综述,并比较各种方法的优点和缺点,为狂犬病的临床快速诊断和深入研究提供科学依据。     

优化利用农广校教育资源构建农民科技教育培训体系

本文通过对作为农业远距离教育主体和农民教育主渠道的农业广播电视学校的资源优势、特点的分析,探讨依托农广校构建农民科技教育培训体系。