林麝肺源ST1249型铜绿假单胞菌的分离鉴定及其全基因组序列分析

【目的】对分离自林麝化脓肺脏的1株疑似铜绿假单胞菌(PA)进行鉴定,并分析其致病和耐药机制,为林麝PA感染化脓性疾病的防控奠定基础。【方法】将病原菌分离纯化后,依次进行生化试验、16S rRNA序列分析、药敏试验和小鼠致病性试验,并通过全基因组测序,对分离菌株进行群体进化和物种分型分析以及基因功能注释。【结果】分离自林麝化脓肺脏的1株疑似铜绿假单胞菌经鉴定与PA相符,命名为FMDP001。药敏试验显示其对阿莫西林、头孢曲松、氨曲南、多粘菌素B和林可霉素耐药;对小鼠半数致死量为9.4×10~5 CFU/mL。全基因组序列分析显示该菌基因组大小为6 955 100 bp,序列类型为ST1249,与B136-33株同源性最高,且两菌株基因组平均核苷酸一致性(ANI)值达98.93%;全基因组中共有357个序列编码FMDP001与致病性相关的基因,根据功能分为黏附、铁摄取、胞外毒性蛋白和调控系统;84个序列编码耐药基因,其中多药耐药外排泵为主要成分。【结论】从林麝化脓肺脏中分离到1株致病性较强的PA,并获得ST1249型林麝源PA的全基因组序列,序列显示该菌携带大量药物外排泵及生物膜形成相关基因,决定其具有多重耐药特性,哌拉西林等可作为该类型PA感染的临床用药。     

毒死蜱对桔小实蝇体内代谢酶的影响

为了解毒死蜱对桔小实蝇体内代谢酶的影响，采用不同浓度的毒死蜱对桔小实蝇敏感种群进行连续处理，测定其体内的羧酸酯酶（CarE）、谷胱甘肽S-转移酶（GSTs）、过氧化氢酶（CAT）、过氧化物酶（POD）的活性。结果表明：随着毒死蜱浓度的增加，桔小实蝇的敏感性出现逐渐下降的趋势，体内的CarE活性得到显著提升（F=43.21，p=0.024），抗性倍数为1.74，GSTs活性也显著上升（F=47.73，p=0.018），抗性倍数为1.98，但对CAT、POD的提升作用较小，表明毒死蜱对桔小实蝇体内的CarE、GSTs活力具有一定的诱导作用。     

福州地区冬菠菜品种比较试验

冬季对7个菠菜品种进行植物学性状、产量、冬性以及抗病性进行比较试验,结果表明,BC2、越超2个品种具备长势强、叶色绿、抗病、冬性强、产量高等特点,可作为福州地区冬季主栽品种。     

早熟薄皮甜瓜新品种香瑞1号的选育

香瑞1号是黑龙江省青冈县瑞雪农业有限责任公司以NY-99为父本、RX-99为母本选育的早熟薄皮甜瓜新品种.全生育期68d,果实发育期27 d.子、孙蔓均可结瓜.果实长圆形,果皮黄白色,果实大小整齐,外形美观,不裂果;中心可溶性固形物14%,品质优.单果质量500～600g,667m2产量3 500 kg左右.田间表现对...     

The mechanical roles of the clasping leaf sheath in cereals: Two case studies from oat and wheat plants

Stem lodging is a common problem in cereal crop production and a main constraint for grain yield improvement. The leaf sheath that surrounds and protects the hollow internodes of stem could provide the plants with a great physical support. However, this biomechanical function has been ignored for several decades in cereal crops. This study aimed to examine the biomechanical properties of basal stem internodes and lodging susceptibility of the whole plants with or without the clasping leaf sheath in wheat (Triticum aestivum L.) and oat (Avena sativa L.) among different genotypes and agronomic practices (including planting densities and nitrogen application rates). The main objective was to quantify the mechanical role of the leaf sheath in oat and wheat crops by a “safety factor” method. On average, the leaf sheath contributed 40%, 68% and 38% of the overall stem bending strength, flexural rigidity and safety factor, in oat, while it accounted for 11%, 24% and 10%, respectively, in wheat plants. The significant contribution of the leaf sheath is due to its vital role in enlarging the peripheral position (i.e., second moment of area) and stiffness (i.e., Young's modulus). The contribution ratios (%) were found to be higher in oat than in wheat plants, due to the greater mass density of leaf sheath and more proficient/prevailing stay-green capability in oat genotypes. This study emphasizes the important mechanical role of clasping leaf sheath on stem internodes of cereals and indicates that the stay-green trait of the leaf sheath can be exploited to design appropriate varieties with improved lodging resistance and great yield potential.     

云南小麦品种（系）锈病和赤霉病抗性功能基因的KASP标记检测

利用5个锈病成株期抗性基因的KASP标记Sr2_ger9 3p、Lr34jagger、CSTM4_67G、Lr68-2、VPM_SNP和抗赤霉病基因Fhb1的KASP标记TaHRC-KASP,对云南省育成的42个小麦品种（系）进行检测,旨在筛选出含有目标基因的优异小麦种质,为云南省持久抗病小麦新品种（系）的选育提供材料。结果表明,4个材料含兼抗型成株抗锈病基因Lr34/Yr18/Sr57,频率为9.52%;6个品种（系）含兼抗型成株抗锈病基因Lr67/Yr46/Sr55,频率为14.29%;7个材料含抗慢叶锈病基因Lr68,频率为16.67%;含兼抗型成株抗锈病基因Sr2/Yr30和成株抗叶锈基因Lr37的材料各有1个,频率均为2.38%;未检测出含抗赤霉病基因Fhb1的品种（系）。云麦69、云麦75、云麦56、宜麦1号和宜麦3号等兼有2个成株期抗锈病基因,可作为今后云南持久抗锈病育种的抗源材料。     

Multiple resistance of Papaver rhoeas L. to 2,4‐D and acetolactate synthase inhibitors in four European countries

The issue of cross‐ or multiple resistance to acetolactate synthase (ALS) inhibitors and the auxinic herbicide 2,4‐D was investigated in Papaver rhoeas L., a common and troublesome weed in winter cereals, in a broad‐scale study across four European countries. A combination of herbicide sensitivity bioassays and molecular assays targeting mutations involved in resistance was conducted on 27 populations of P. rhoeas originating from Greece (9), Italy (5), France (10) and Spain (3). Plants resistant to the field rate of 2,4‐D were observed in 25 of the 27 populations assayed, in frequencies ranging from 5% to 85%. Plants resistant to ALS‐inhibiting herbicides (sulfonylureas) were present in 24 of the 27 populations, in frequencies ranging from 4% to 100%. Plants resistant to 2,4‐D co‐occurred with plants resistant to sulfonylureas in 23 populations. In four of these, the probability of presence of plants with cross‐ or multiple resistance to 2,4‐D and sulfonylureas was higher than 0.5. ALS genotyping of plants from the field populations or of their progenies, identified ALS alleles carrying a mutation at codon Pro197 or Trp574 in 2,4‐D‐sensitive and in 2,4‐D‐resistant plants. The latter case confirmed multiple resistance to 2,4‐D and ALS inhibitors at the level of individual plants in all four countries investigated. This study is the first to identify individual plants with multiple resistance in P. rhoeas, an attribute rarely assessed in other weed species, but one with significant implications in designing chemical control strategies.     

轻钢结构抗震节能体系在“塞上农民新居”中的应用

针对宁夏地区农民传统住宅抗震性差，建筑外围护结构保温性能差，采暖系统能源消耗量大，环境污染严重等问题，提出采用轻钢结构配以轻质保温板材的轻钢结构抗震节能体系，以期为宁夏农村住宅设计提供指导性建议。