烟草赤星病菌生理及农药毒力测定研究

本试验对烟草赤星病菌(Alternaria alternata)进行了生理和农药毒力测定。结果表明:该菌最适生长温度为26～28℃;最低生长温度6℃,最高生长温度37℃。分生孢子致死温度分别为50℃5分钟和49℃10分钟,幼菌丝致死温度分别为50℃10分和52℃5分钟。菌丝生长最适pH值为6～8,孢子萌发最适pH值6～7,生长和萌发最低pH值均为3。64％杀毒矾和58％瑞毒霉锰锌对该菌抑制效果最好。     

烟草赤星病菌嘧菌酯抗性突变体的诱导及其生物学特性

为探究烟草赤星病菌对嘧菌酯的抗药性风险水平,通过对烟草赤星病菌在室内含药平板上的菌丝药剂驯服和分生孢子紫外诱变,进行突变体的生物学特性的研究,并对突变体靶标基因细胞色素b进行了测序分析。获得了4株嘧菌酯抗药性突变体。其中,菌丝药剂驯服未获得突变体;孢子紫外诱变获得4株突变体,突变率约为0.004%,突变体抗性倍数分别为42.50、282.50、515和107.50。4株突变体均降低了对嘧菌酯的敏感性。适合度研究表明,抗药性突变体具有同敏感菌株同样的分生孢子萌发能力和致病能力;菌丝生长速率较敏感菌株有所降低,3株突变体的分生孢子产量较敏感菌株增强,1株突变体较敏感菌株减弱。抗药性靶基因细胞色素b基因部分序列分析表明,突变体在129位和143位的碱基与敏感菌株完全相同,未发生任何突变。初步认为烟草赤星病菌对嘧菌酯的抗性风险水平较低。     

线粒体旁路氧化途径抑制剂水杨肟酸(SHAM)协同下烟草赤星病菌对嘧菌酯的敏感性

测定了线粒体旁路氧化途径抑制剂水杨肟酸(SHAM)协同下烟草赤星病菌对嘧菌酯的敏感性。结果表明:嘧菌酯抑制病原菌菌丝生长和孢子萌发的EC₅₀值分别为25.8300 mg/L和0.0500 mg/L,在100 mg/L SHAM协同下,EC₅₀值分别降低为15.5200和0.0038 mg/L;SHAM对烟草赤星病菌菌丝的生长和分生孢子的萌发没有影响。研究说明SHAM增强了嘧菌酯对烟草赤星病菌的毒力,线粒体电子传递的旁路氧化途径存在于烟草赤星病菌中,且在孢子萌发中的增效强于菌丝生长阶段。      

烟草鸢尾丝囊霉菌的生物学特性及分子检测

针对近年来河南省许昌、洛阳、三门峡等部分烟区烟草漂浮苗鸢尾丝囊霉根腐病发生较重的问题,采用菌丝生长速率法初步分析了病原菌的生物学特性,并根据NCBI数据库中鸢尾丝囊霉菌代表菌株CBS 524.87的5个编码基因CDS序列,设计筛选鸢尾丝囊霉菌的特异性扩增引物并应用。生物学特性分析结果表明,在PDA培养基上,鸢尾丝囊霉菌菌丝生长的适宜温度为25～35℃,致死温度为50℃,处理10min;生长适宜pH为4.0～8.0,最适pH为6.0;连续光照条件有利于菌丝生长。筛选获得了特异性扩增鸢尾丝囊霉菌的引物对7个,对于基因组DNA扩增的灵敏度约为0.182 ng/μL;利用特异引物AiT3分别对接种育苗基质和烟苗进行分子检测,可特异性的检测出鸢尾丝囊霉菌,检测的灵敏度分别为每克基质含菌量为2.5×10^-2 g病原菌菌丝和0.5 ng/μL烟苗根系基因组DNA。本研究为鸢尾丝囊霉菌的快速分子检测提供了技术支撑,对苗期鸢尾丝囊霉根腐病病原的准确识别和预测预报提供了依据。     

抗烟草赤星病芽孢杆菌B102菌株的筛选及抑菌作用

从山东烟田烟草根际和根围土壤中分离到157株细菌,筛选出对烟草赤星病菌Alternaria alternata有明显抑菌作用的细菌菌株7个.其中B102菌株对烟草赤星病菌抑菌作用明显,抑菌带宽度达13.0 mm.采用异步培养、对峙培养、含细菌培养等方法,测定发酵滤液及代谢产物对病原菌的作用机制.结果表明,B102菌株对病原菌的抑制作用主要依赖于其产生的抗高温的代谢产物,可抑制病菌菌丝生长、孢子萌发、菌丝细胞破裂、内含物外泄,致使病菌丧失侵染能力.B102菌株代谢产物经高温及不同的pH值条件处理后仍表现出较高的抑菌活性,表明B102菌株对外界环境条件的稳定性强.     

烟草赤星病菌对嘧菌酯及其添加水杨肟酸后的敏感性检测

为了解烟草赤星病菌对嘧菌酯的敏感性现状,采用菌丝生长速率法,检测了采自山东和湖北烟区的33株烟草赤星病菌对嘧菌酯的敏感性,分析了水杨肟酸协同下烟草赤星病菌对嘧菌酯敏感性的影响。结果表明:嘧菌酯对所有供试烟草赤星病菌的EC₅₀介于60.5230~111.7918 mg·L-1,平均为83.9068±2.4339 mg·L-1;嘧菌酯对采自山东烟区和湖北烟区的赤星病菌的平均EC₅₀分别为82.7986±2.5515 mg·L-1和88.0230±6.6785 mg·L-1。在水杨肟酸协同作用下,嘧菌酯对所有供试烟草赤星病菌毒力的EC₅₀介于19.9090~35.6684 mg·L-1,平均为29.2007±0.7801 mg·L-1,比嘧菌酯单独作用毒力提高了0.70~2.98倍,平均提高了1.87倍;添加水杨肟酸的嘧菌酯对采自山东和湖北烟区的赤星病菌毒力的平均EC₅₀分别为28.5494±0.8914 mg·L-1和31.6197±1.3290 mg·L-1,与嘧菌酯单独作用相比,毒力分别提高了1.90和1.78倍。研究表明,嘧菌酯对烟草赤星病菌的菌丝生长具有一定的抑制作用,添加水杨肟酸能够显著提高嘧菌酯对烟草赤星病菌的毒力,但不同菌株之间的提高倍数有差异。      

温度、湿度、接菌量及pH对烟草青枯病菌致病力的影响

烟草青枯病菌是土传病原细菌,其致病力易受多种因素影响。采用穿刺法接种离体叶片,系统性地研究了温度、湿度、接菌量和pH对烟草青枯病菌致病力的影响。试验范围内青枯病菌可致病的病原菌数量为1.3~1.3×108 cfu,1.3×108 cfu病斑面积最大;致病的温度范围为20~35℃,最适为30~35℃,病害潜伏期随着温度升高而变短;40%~100%的相对湿度范围内均可发病;致病pH范围为5.0~8.0,最适发病pH为6.0。影响青枯病菌致病力的关键因子为温度和pH,湿度不是青枯病发生的关键因素,结果为研究烟草青枯病发生机制提供了科学依据。     

恩施烟区烤烟黑胫病菌致病力测定及抗性品种差异鉴定

为有效进行恩施烟区烟草黑胫病的防控,本研究采用菌丝块茎基部创伤接种法鉴定了恩施烟区烟草黑胫病菌的致病力。根据黑胫病菌菌株接种K326、红花大金元、云烟202后的AUDPC （病害流行曲线下面积）数值进行了聚类分析,将恩施烟区烟草黑胫病菌划分为I、Ⅱ、Ⅲ 3种致病型。3种致病型病原菌没有表现出典型的强、中、弱致病特性。7个抗性烟草品种对不同致病型黑胫病菌表现出抗性差异,革新3号对3种致病型菌株均表现出较好的抗性。     

油菜黑胫病菌Leptosphaeria biglobosa生物学特性研究

为了解我国油菜黑胫病病原菌（Leptosphaeria biglobosa）的生物学特性,在实验室里研究了温度、pH值、光照、碳源及氮源等条件对该病菌营养生长及分生孢子产生的影响。结果表明：病原菌在5℃～35℃均可进行营养生长并产孢,最适生长和产孢温度为25℃;在pH4～10的范围内该菌均能生长并产孢,在pH7的条件下生长最快,产孢最多。光暗交替有利于菌丝生长和产孢,而持续光照不利于菌丝生长,尤其不利于产孢。最适的碳源、氮源分别是可溶性淀粉、牛肉膏。分生孢子的致死温度为52℃。     

安徽省烟草根黑腐病病原鉴定及生物学特性分析

为了明确引起安徽省烟草根黑腐病的病原菌种类,选择具有典型症状的烟草根黑腐病烟株,采用胡萝卜圆片法对病原菌进行了分离。同时根据病原菌的培养形态和r DNA-ITS区序列对病原菌种类进行了鉴定,采用灌根法对病原菌进行致病性测定,并对病原菌的生物学特性进行研究。鉴定结果表明,分离得到的病原菌菌株为基生根串珠霉(Thielaviopsis basicola),对烟草品种云烟87有致病力。生物学特性分析表明,病原菌生长的最适培养基为V8,菌丝生长和孢子萌发最适温度为25℃、最适p H为6,分生孢子致死温度为53℃。该病原菌能有效利用淀粉、麦芽糖、葡萄糖等碳源以及尿素、硝酸锌等氮源。     

2010年河南省部分食品中重金属污染状况分析

了解河南省部分食品中重金属污染的现状。方法 在河南省18个省辖市采集8大类3 657份食品样品,按照国家标准检测食品中铅、镉和汞的含量,检测结果按照GB 2762—2012《食品安全国家标准食品中污染物限量》进行评价。结果 河南省部分食品中铅含量的平均值为0.34 mg/kg,总体超标率为8.8%(320/3 656),其中粮食、肉类和蔬菜中超标率较高,分别为17.2%(95/552)、14.5%(85/587)和10.7%(57/534);部分食品中镉含量的平均值为0.054 mg/kg,总体超标率为3.9%(143/3 657),其中食用菌和蛋类中超标率较高,分别为9.6%(49/508)和8.1%(42/518);部分食品中汞含量的平均值为0.077 mg/kg,总体超标率为8.3%(303/3 657),其中蔬菜和粮食中超标率较高,分别为25.3%(135/534)和12.3%(68/551)。结论 河南省部分食品中铅、汞污染情况较为严重,其中粮食、蔬菜和肉类食品中污染情况尤为突出,需要加强监管。     

Changes in smoking prevalence in Ukraine in 2001-5

Objectives

To analyse trends in smoking prevalence in Ukraine from three surveys conducted in 2001–5, and to explore correlates of observed changes, in order to estimate the stage of tobacco epidemic in Ukraine.

Design

Repeated national interview surveys in Ukraine in 2001, 2002 and 2005.

Main outcome measure

Prevalence of current smoking among the population aged ⩾15 years.

Results

The age‐standardised prevalence of current smoking in Ukrainian men was 54.8% in 2001 and 66.8% in 2005. Among Ukrainian women, prevalence increased from 11.5% in 2001 to 20.0% in 2005. ORs for yearly increase in prevalence were estimated as 1.164 (95% CI 1.111 to 1.220) for men and 1.187 (1.124 to 1.253) for women, which implies that, on average, 3–4% of men and 1.5–2% of women living in Ukraine join the smoking population each year.

Conclusions

In Ukraine, smoking prevalence is increasing in most population groups. Among men, the medium deprivation group with secondary education has the highest smoking prevalence. Among women, while the most educated, young and those living in larger cities are the leading group for tobacco use, other groups are also increasing their tobacco use. Tobacco promotion efforts appear to have been significantly more effective in Ukraine than smoking control efforts. The decrease in real cigarette prices in Ukraine in 2001–5 could be the main factor explaining the recent growth in smoking prevalence.Ukraine is a large eastern European country with high smoking prevalence. Tobacco products are widely available at very low prices, and the transnational tobacco industry is extremely successful in promoting its products and lobbying for its interests in the legislative field. Advocacy of tobacco control has only recently achieved some success in the legislative field, with the first tobacco control law being adopted in late 2005. Ukraine ratified the Framework Convention on Tobacco Control in 2006, but there is still much cause for concern regarding the enforcement and effectiveness of the adopted legislative measures. Unfortunately, the government is not yet involved in nationwide surveillance of the tobacco problem, and the available data have mostly been gathered with funding from foreign donors. Several attempts have been made to measure the extent of the tobacco epidemic in the countries of the former Soviet Union (FSU).^{1,2,3,4,5,6,7} Most of these studies have shown rather high smoking prevalence among men (50–70%) and comparatively low prevalence among women (5–20%). Most countries in the FSU have similar smoking rates, while certain trends are shown to be related to the differences in how the transnational tobacco industry succeeds in every national tobacco market.⁶ Unfortunately, few studies have been published showing trends in smoking prevalence in the FSU.⁷ In Ukraine, two studies^3,4 provided point estimates of smoking prevalence.The aim of this study was to analyse trends in smoking prevalence in Ukraine, on the basis of three surveys conducted in 2001–5, and to explore correlates of observed changes in order to estimate the stage of the tobacco epidemic in Ukraine.     

脂质体在食品中的应用及体外消化研究进展

脂质体是由双亲性物质如磷脂组成的内部为水相、具有类细胞膜结构的双分子层闭合囊泡,因其具有保护、运载、靶向和缓释等特点,目前已在食品营养、医药、化妆品、农业等领域表现出极大的应用潜能。本文简要介绍了脂质体的性质及特点,重点综述了脂质体在脂类、抗氧化剂、酶与蛋白质以及维生素和矿物质等食品领域的研究及应用,最后概述了脂质体作为食品营养因子运载体系在模拟体外胃和肠道消化的研究进展。