分子标记辅助选择改良水稻不育系臻达A及其杂交种的稻瘟病抗性

水稻抗稻瘟病基因Pi25是一个遗传传递能力强的广谱抗性基因。本研究以携带抗稻瘟病基因Pi25的BL27为抗源供体,与优质、配合力强、感稻瘟病的水稻保持系臻达B为受体亲本进行杂交、回交创制水稻抗病保持系新种质,再与臻达A测交和回交进行不育系转育,结合分子标记辅助选择和农艺性状筛选,获得3个抗性基因纯合、农艺性状和开花习性均与臻达A相似的改良不育系株系。利用福建省近年来致病性代表的22个稻瘟病菌株对3个改良不育系及其15个杂交种进行抗性鉴定,3个改良不育系的抗性频率为95.45%~100%,15个杂交种的抗性频率均达75%以上,而原始对照臻达A及其杂交种的抗性频率仅为54.55%和40.91%~63.64%。自然病圃诱发鉴定表明,3个改良不育系的叶瘟和穗颈瘟均为0级,表现高抗,而对照臻达A的叶瘟为5级,穗颈瘟为7级,表现感病;15个杂交种均表现良好的稻瘟病抗性。进一步分析比较15个杂交种的产量、农艺性状和稻米品质表现,结果表明臻达A-Pi25-3改良不育系的综合性状表现最优,继续回交转育,于2015年育成了稻瘟病抗性强、配合力好、群体整齐和性状稳定的不育系,命名为157A。研究表明,抗稻瘟病基因Pi25不仅在水稻不育系臻达A的遗传背景下的抗性表达完全,且在不同水稻恢复系测交种的背景下同样表现出较高水平的抗性,说明抗性基因Pi25对不育系稻瘟病改良的效果明显。创制的新不育系157A的稻瘟病抗性显著提高,还基本保留了原来不育系高配合力等优良特性,为选育高产、优质、抗病杂交稻新品种提供了不育系新种质。     

水稻恢复系M630稻瘟病抗性改良及其代谢组研究

稻瘟病是水稻的主要病害之一,改良水稻稻瘟病抗性对水稻生产、推广具有重要意义.本研究以携带广谱抗稻瘟病基因Pi9材料9311-Pi9为供体,水稻优良恢复系M630为受体,将杂交、回交与分子标记辅助选择和背景筛选相结合,获得改良恢复系M630-Pi9.主要农艺性状和稻米品质分析显示改良后的M630-Pi9及其杂交组合徽两优...     

定向改良超级早稻中早39稻瘟病抗性

稻瘟病是水稻生产中最具毁灭性的病害之一,稻瘟病菌生理小种变异快,抗性品种推广3～5年后抗性衰退风险较高,改良及培育抗稻瘟病菌新致病小种的品种是防治该病害最经济有效的方法。本研究以携带稻瘟病抗性基因Pi25的材料R6为供体亲本,超级早稻中早39为受体亲本和轮回亲本,通过杂交、回交和自交以及分子标记辅助选择技术,并结合室内喷雾接种、田间注射接种叶瘟以及病圃自然发病区穗颈瘟鉴定。综合考量抗性表型、基因型以及农艺性状,筛选出4个携带Pi25基因,叶瘟及穗颈瘟抗性较中早39提高,且农艺性状良好的株系FY82、FY90、FY125、FY137,同时对育成品系的系谱组成和抗性相关位点进行研究,初步阐明了育成品系较轮回亲本抗性水平提高的遗传基础。     

分子标记辅助选择Pi9基因改良籼型三系不育系三香A稻瘟病抗性

以籼稻品系75-1-127作为广谱持久抗稻瘟病基因Pi9的供体亲本,先后以籼型三系保持系三香B及其不育系三香A为受体亲本,利用Pi9基因内共显性InDel标记CoInDF1R1开展分子标记辅助选择连续回交育种,定向改良三香B和三香A的稻瘟病抗性.以三香B、三香A、75-1-127和感病对照CO39为材料,用来自国内外不...     

宁夏水稻代表性种质及后代抗稻瘟病基因型分析北大核心CSCD

以96份宁夏水稻代表性种质资源和47份杂交后代为试验材料,采用宁夏稻瘟病菌生理小种人工接种和自然诱发相结合的方法对其进行稻瘟病抗性的大田鉴定和病圃鉴定,评价了每个材料的稻瘟病抗性;同时采用8个主效抗稻瘟病基因的功能标记对上述材料进行抗病基因的分子检测,得到了28个不同的抗稻瘟病基因型,将不同基因型的稻瘟病抗性评价进行了差异显著性分析。结果表明,同时含有Pita、Pib、Pikm、Pikh、Pi9和Pi5共6个抗病基因组成的基因型的水稻材料对稻瘟病的抗性极显著高于其他基因型的抗性。Pita基因单独与Pikm、Pikh、Pi2、Pi5基因聚合时均表现出正向聚合效应,其中Pita与Pikh基因的聚合效应最强。当Pib与Pita+Pikh聚合时,表现出负向聚合效应。这为宁夏地区通过基因聚合方法选育广谱持久抗稻瘟病水稻新品种提供了重要的参考依据。     

三基因聚合改良恢复系福恢673的稻瘟病抗性

为了改良水稻优良恢复系福恢673的稻瘟病抗性,以该恢复系为轮回亲本,以携有3个稻瘟病抗性基因(Pi-1、Pi-9和Pi-k~h)的优质恢复系金恢1059为供体亲本,通过回交育种结合分子标记辅助选择,选育出10个导入了这3个抗稻瘟病基因的福恢673近等基因系,其遗传背景恢复率为92.96%–98.59%。抗性鉴定结果表明,这些近等基因系及其与不育系宜香A配制的杂种一代均表现抗稻瘟病,抗性明显强于对照福恢673和宜优673,且半数以上杂种一代基本保留了原组合的主要优点。用近等基因系Line 9配组的杂交稻新组合两优7283和金泰优683在区试中均表现出产量高、稻瘟病抗性强、生育期适中等特点,表明该近等基因系具较好的应用前景。     

抗稻瘟病水稻资源抗性基因Pita、Pib、Pi9以及Pikm的分布研究

利用抗稻瘟病水稻资源品种杂交,聚合多个抗性基因是培育持久抗稻瘟病水稻新品种的主要育种途径.利用分子标记技术对水稻抗性资源进行基因型鉴定是分子辅助聚合育种的基础.通过以亚华种业科学院稻瘟病病圃抗病水稻资源为材料,利用特异性分子标记对Pi9、Pita、Pib以及Pikm基因在水稻抗稻瘟病资源的分布进行了鉴定,初步建立了抗性基因数据库.同时对抗性基因及与抗性反应的相关性进行了探讨,结果表明以Pi9为主效基因,同时聚合Pita和Pib抗性基因能提高持久抗稻瘟病能力.     

多种优质高分子量谷蛋白亚基的聚合育种研究

用携带HMW-GS14 15的小偃6号作为轮回亲本,携带HMW-GS5 10的法国优质面包小麦品系707作为供体亲本,在回交后代的BC1、BC2、BC3、BC3F1、BC3F2代其它农艺性状选择的基础上,利用1对特异引物逐代检测出携带优质,Dx5基因的单株进行回交和自交。BC1代中随机检测的58个单株的Dx5基因分布符合1对等位基因的遗传分离比例1：1;BC1代小麦相同3个单株3个不同生长季节Dx5基因检测的结果完全一致,检测结果非常稳定;已将优质Dx5基因导入BC3F2后代的部分单株内;携带Dx5基因的株系XN89-7-3微量SDS沉淀值为18．8mL,比小偃6号提高了23．68％;蛋白质电泳筛选出了6个聚合多种优质亚基且编码基因纯合的单株,微量SDS沉淀值为19．9mL,比小偃6号提高了30．92％;选择农艺性状与轮回亲本相似并具有Dx5基因特异扩增产物的单株进行回交或自交,可加快回交转育的进度。实践证明,回交转育与分子标记辅助选育相结合的育种方法是快速定向聚合多种优质HMW-GS基因的有效方法之一。     

利用分子标记辅助选择改良珍汕97的稻瘟病抗性

利用回交育种中产生的回交群体，结合前人的研究结果构建了Pi1基因区域的局部分子标记连锁图，通过BC1F2家系的接种结果判断其基因型。将Pi1定位在RFLP标记RZ536与SSR标记RM144之间，图距分别为9．7cM、6．8cM，从而建立了一套完整的以PCR为基础的分子标记辅助选择体系。通过分子标记和抗性验证两种选择方式相结合，经过三代回交将Pi1区段快速导入受体亲本珍汕97B中。在BC3F1中利用15条ISSR引物扩增的167条随机分布在基因组中的多态性带筛选背景，得到4个背景较好的单株。经过纯合筛选及抗性验证后共得到17个带有抗性基因Pi1的改良珍汕97株系。试验表明微卫星标记在正向选择、负向选择及背景选择中都起到极大的作用。     

国外引进水稻种质资源的稻瘟病抗性基因检测与评价

为了筛选出福建省水稻稻瘟病重发区育种中可利用的新抗性资源,在福建省上杭县对156份外引水稻种质资源进行了2年田间自然诱发鉴定,并对Pi2、Pi9、Pi5、Pi54、Pikm、Pita、Pia和Pib等8个稻瘟病抗性基因做了分子检测。结果表明:156份资源对苗瘟、叶瘟、穗颈瘟和综合抗性表现抗病的分别有10份、14份、29份和26份,且苗瘟抗性级别与叶瘟抗性级别(r=0.816,P<0.01)、苗瘟抗性级别与穗颈瘟抗性级别(r=0.347,P<0.01)、以及叶瘟抗性级别与穗颈瘟抗性级别(r=0.344,P<0.01),均呈极显著正相关。分子标记检测到携带稻瘟病抗性基因Pi9、Pi2、Pi54、Pikm、Pi5、Pib、Pia和Pita的水稻资源分别有1、6、20、22、37、88、101和106份,其中携带稻瘟病抗性基因Pi9和Pi2的水稻资源的抗性表现较好,表现抗病的超过60%,携带其他稻瘟病抗性基因的水稻资源表现抗病的均在50%以下;水稻资源携带0~6个稻瘟病抗性基因,随着携带抗性基因数目增加,抗病率呈上升趋势,综合抗性等级呈下降趋势。进一步研究发现,携带Pi9+Pi5+Pikm+Pia、Pi5+Pib+Pita+Pikm+Pia和Pi2+Pi54+Pib+Pita+Pikm+Pia等3个基因型的水稻资源,稻瘟病抗性较好。最后,筛选了8份稻瘟病抗性较好的材料,提供育种者参考、利用。     

我国麦蚜抗药性及研究现状

麦蚜是危害我国小麦Triticum aestivum L.生产的主要害虫,具有分布广、数量大、繁殖力强以及远距离迁飞等特点,不仅直接吸食小麦汁液,还传播多种植物病毒,每年造成小麦减产10%~30%。目前对麦蚜的防控主要以化学防治为主,但由于化学杀虫剂长期或不合理的使用,多地麦蚜对常用杀虫剂产生了不同程度的抗性。本文从麦蚜抗药性测定方法、抗性水平及交互抗性、代谢和靶标抗性机制、以及麦蚜抗药性综合治理等方面进行了综述,以期为麦蚜的防治及杀虫剂的持续合理使用提供理论参考和依据。     

Stability analyses for estimating relative durability of quantitative resistance

Summary Experiments in which a series of host cultivars are inoculated in all combinations with a series of pathogen isolates have been used to detect specificity in the host resistance. A theoretical model of polygenic resistance involving both general and specific interactions with pathogen virulence was developed to test the abilities of statistical analyses to discriminate between host genotypes with different levels of general and specific resistance. Estimates of levels of specific resistance could be obtained in regressions of disease severity scores for each host cultivar X pathogen isolate combination vs. the virulence index of each isolate. If the virulence index was based on the mean disease severity induced by the isolate over all host cultivars, the slopes of the regression lines were correlated with the levels of specific resistance in host cultivars. If the virulence index was based on the disease severity induced by the isolate on a host cultivar with a minimum of specific resistance, the mean squares for deviations from the regression were correlated with the levels of specific resistance in host cultivars. A method was developed to consistently choose host cultivars with minimum specific resistance. The two regression analyses gave estimates of specificity in randomly generated, model genotypes of approximately equal accuracy, although the second method appeared to be more accurate when the numbers of loci controlling resistance and virulence were small. The best estimates of numbers of genes for specific resistance were obtained by calculating a rating based on mean disease severity, the mean square for deviation from the regression on the virulence index based on disease severity on the cultivar with minimum specific resistance and the slope of the regression on the virulence index based on the mean disease severity. The best estimates of proportions of resistance genes that were specific were obtained by calculating a rating based on the above deviation mean square and slope alone.Cooperative investigation of the U.S. Department of Agriculture, Agricultural Research Service and the North Carolina Agricultural Research Service. Journal Series Paper No. 8326 of the North Carolina Agricultural Research Service     

PC12 Variants Deficient in Catecholamine Transport

We have isolated PC12 cell variants deficient in transporter-mediated uptake of 3,4-dihydroxyphenylethylamine (dopamine). The variants either were obtained nonselectively, or they were selected by resistance to guanethidine or N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Dopamine uptake into guanethidine-resistant cells occurred with a decreased Vmax; the Km for dopamine and inhibition by guanethidine were normal. MPTP-resistant cells lacked the capacity to take up dopamine. Most of the variants resembled wild-type PC12 in their response to nerve growth factor and the storage and secretion of dopamine. MPTP-resistant cells exhibited several deficiencies in addition to dopamine transport, i.e., no measurable storage of dopamine or acetylcholine and no observable response to nerve growth factor. Wild-type and variant cells were compared with respect to the labeling of cell proteins with [3H]xylamine, which binds covalently to certain proteins apparently only after entering PC12 via the catecholamine transporter. When intact variant cells were used, there was markedly reduced labeling of the proteins by [3H]xylamine. Almost all of these proteins were readily labeled when cell homogenates were exposed to [3H]xylamine. However, MPTP-resistant cells were missing three of these proteins. Northern blot analysis with cDNA clones revealed that the MPTP-resistant cells had markedly reduced levels of several specific mRNA species.     

西花蓟马的抗药性及其治理策略

西花蓟马Frankliniella occidentalis（Pergande）是世界性的园艺作物上的重要害虫,几乎对每种类型的杀虫剂均产生了抗药性,包括有机磷、氨基甲酸酯、拟除虫菊酯类杀虫剂和多杀菌素等。本文对国外西花蓟马的抗药性发展现状和抗性机制进行了总结,并提出了抗性治理策略,即科学合理使用杀虫剂,结合栽培防治、物理防治、生物防治和寄主植物抗性等方式降低杀虫剂对西花蓟马的选择压,从而达到抗性治理的目的。     

甜菜夜蛾的抗性及抗性机理研究进展

甜菜夜蛾Spodoptera exigua(Hübner)是世界性农业害虫,近年来在我国由次要害虫上升为主要害虫。甜菜夜蛾对很多种化学杀虫剂和生物杀虫剂产生了抗性。本文分别阐述了甜菜夜蛾对常用杀虫剂如有机磷类、拟除虫菊酯类、氨基甲酸酯类、生长调节类杀虫剂、Bt杀虫剂等的抗性发展现状,并且对抗药性机理进行了总结,提出了抗性治理措施。     

Selection of a dexamethasone-resistant H-4-IIE-C3 rat hepatoma tissue-culture line

Summary Exposure of H-4-IIE-C3 rat hepatoma cell cultures to the synthetic glucocorticoid, dexamethasone, results in an inhibition of cellular proliferation which is not the result of steroid-induced cytolysis. A significant decrease in both the rat of DNA synthesis and DNA content precedes, a detectable effect on cell number. Continuous culture of H-4-IIE-C3 cells in medium containing 10⁻⁵ m dexamethasone results in the selection of a steroid-resistant cell population that has the growth characteristics of unselected sensitive cultures and shows normal steroid induction of tyrosine transaminase. Selection is a slow process requiring 24 to 36 months to obtain, a phenotypically stable resitant cell line, and can be subdivided into three phases—a sensitive phase, adaptation and resistance. A comparison of the karyotypes of unselected and resistant cultures shows that the selection process enriches for a dexamethasone-resistant subpopulation. This work was supported by Special Grant No. 716 from the California Division of the American Cancer Society, and a grant-in-aid from the San Diego State University Foundation.     

害虫及害螨对阿维菌素抗药性研究进展

阿维菌素(avermectins)是一类新型高效广谱的生物源农药,对多种害虫及害螨具有极好的防效。随着阿维菌素在害虫及害螨防治中的广泛应用,害虫和害螨对其的抗性问题日益受到关注。文章综述国内外的最新研究结果表明:小菜蛾Pluttella xylostella(L.)、二斑叶螨Tetranychus urticate Koch等已对阿维菌素产生抗性,对阿维菌素产生抗性的害虫和螨并不总是表现适合度劣势,且抗性一旦产生敏感性较难以恢复;抗性遗传多数由多基因、不完全隐性控制;抗性机理涉及多种因素。综合分析发现害虫和螨对阿维菌素存在较大的、潜在抗性风险。     

Herbicide resistance—what have we learned from other disciplines?

Herbicide resistance is a growing threat to agriculture and has parallels to resistances to fungicides and insecticides. However, there are many reasons to treat the resistance to herbicides differently. To highlight these similarities and differences, three pests, a weed, an insect, and a disease that have shown the ability to rapidly develop resistance to a variety of products and product classes were used as illustrations. The situation in herbicide resistance is approaching a point already experienced by the other pest control disciplines, and thus, it is worthwhile to revisit their experiences.