小麦条锈菌国际鉴别寄主Lee对中国条锈菌系CY23的抗性遗传分析

采用常规杂交方法,以国际小麦条锈菌鉴别寄主Lee与感病品种铭贤169杂交、自交、测交,获正、反交的F1、F2和BC1代。根据条锈菌小种的毒性谱,选用CY23单孢菌系,对其双亲及其杂交后代进行苗期抗性鉴定和统计分析,明确抗性基因数目、显隐性、互作方式和抗性特点。结果表明,在正交情况下,Lee对CY23菌系的抗性由1对显性基因和1对隐性基因互补控制,反交情况下也由1对显性基因和1对隐性基因互补控制,正反交分析结果一致,说明Lee对CY23的抗性属核遗传,由1对显性基因和1对隐性基因互补控制。通过对CY23毒性分析和对Yr7、Yr22和Yr23遗传特点研究,表明Lee对CY23抗性的1对显性基因和1对隐性基因分别为Yr7和Yr23,两者互补控制对CY23的抗性。在抗性鉴定中可用CY23区别Yr22与Yr23,并作为标准菌系用于基因推导分析。     

栽培措施对烟蚜和烟草花叶病关系的初步研究

烟蚜(Myzus persicae)的发生在很大程度上受不同烟草品种、种植密度和施肥量的影响。其中烤烟G₁₄₀上的烟蚜发生量最多,病毒病发病率亦较高,NC₈₉烟上蚜虫量少,病毒病发病率亦较低:适当提高种植密度和降低氮肥使用量可以减轻烟蚜特别是有翅蚜的发生。大田调查及罩笼试验,均表明有翅烟蚜发生量与烟草花叶病毒病发病率之间存在显著的正相关(r=0.8349),进一步证明江苏烟区烟蚜是烟草黄瓜花叶病毒(CMV)的主要传播者。药剂试验表明,苗期连续用氧化乐果防治可有效地控制烟蚜的危害,并能减轻烟草花叶病毒病的发生。     

四种化合物诱导马铃薯抗晚疫病的效果及其相关防御基因表达分析

为探究水杨酸、壳聚糖、麦角甾醇和纤维二糖4种化合物诱导马铃薯抗晚疫病的效果及其作用机理,采用整株喷雾法、挑战接种法、菌丝生长速率法分析4种化合物对马铃薯晚疫病的预防作用及对其病原菌致病疫霉Phytophthora infestans的离体抑制效果,利用实时荧光定量PCR技术测定4种化合物诱导后马铃薯病程相关蛋白和防御酶基因的调控表达情况。结果显示,水杨酸、壳聚糖、纤维二糖和麦角甾醇分别处理马铃薯植株24 h后接种致病疫霉,在多个浓度下对晚疫病均有不同程度的诱导抗性,其中在1 000 μmol/L浓度（壳聚糖浓度为1 000 mg/L）时诱导抗性最好,较对照显著提高,诱抗效果分别为54.73%、61.99%、59.73%和48.59%。壳聚糖对马铃薯晚疫病的诱抗效果高于其它3种化合物,且只有壳聚糖能显著抑制致病疫霉的菌丝生长和孢子囊形成,说明壳聚糖除了能诱导作物产生抗病性外,还具有直接抑菌作用。4种化合物诱导后马铃薯病程相关蛋白基因PR1、过氧化物酶基因POD和多酚氧化酶基因PPO的表达量在施用早期均显著升高。表明这些化合物能诱导马铃薯对晚疫病产生抗性,可能与马铃薯体内过氧化物酶、多酚氧化酶的活性和抗病信号传导途径关键基因PR1的表达有关。     

钙粘蛋白氨基酸点突变介导红铃虫对Cry1Ac的抗性

为明确室内筛选的红铃虫Pectinophora gossypiella抗性品系AQ-R对Cry1Ac的抗性机制,采用室内生物测定法明确该品系对Cry1Ac和Cry2Ab的敏感性,通过遗传杂交和基因克隆分析抗性基因的显隐性及突变位点,并进行细胞学试验分析突变蛋白的亚细胞定位。结果显示：红铃虫AQ-R抗性品系对Cry1Ac的抗性倍数为181.67倍,对Cry2Ab没有交互抗性;该品系携带了一种新型的隐性钙粘蛋白抗性等位基因PgCad1,其编码蛋白的钙粘蛋白重复区、前蛋白区和近膜区共发生了17个氨基酸替换。表达野生型PgCad1-s基因的Hi5细胞对Cry1Ac敏感,且钙粘蛋白定位于细胞膜;而表达抗性PgCad1-r基因的Hi5细胞则对Cry1Ac不敏感,且钙粘蛋白错误定位到内质网。表明钙粘蛋白氨基酸点突变能导致其定位错误,从而促成红铃虫AQ-R品系对Cry1Ac产生抗性。     

小偃9366抗条锈病基因的遗传分析及分子作图

为了明确小偃9366抗条锈病遗传特点,对小偃9366与铭贤169及其杂交F₁、F₂、F₃和BC₁F₁代进行温室苗期抗条锈性遗传分析,选取400余对SSR引物对接种CYR31的群体进行分子标记,并利用目标基因的侧翼引物分析99个黄淮麦区主栽小麦品种。小偃9366对CYR25的抗病性由1显、1隐2对基因独立控制,对CYR27的抗病性由3对显性基因控制,其中2对基因表现累加作用,对CYR30 和CYR31的抗病性均由1对显性基因独立控制,对Su11-4的抗性由2对隐性基因独立控制。位于2AL上的6个标记Xwmc794、Xwmc455、Xwmc261、Xgwm47、Xgwm294和Xcfd168与抗CYR31基因(暂命名Yrxy9366)连锁,与目的基因的遗传距离分别为10.8、6.5、3.2、4.4、16.0和32.8 cM,将Yrxy9366定位在2AL上。利用Xwmc261、Xgwm47两个引物分析99个黄淮麦区主栽小麦品种,仅5%检测到同源片段。研究表明Yrxy9366是一个新的抗病基因。     

侵染葫芦的黄瓜绿斑驳花叶病毒广西分离物分子鉴定

从广西南宁市郊温室大棚中的葫芦[Lagenaria siceraria(Molina)Stand.]上采集到一个表现脉绿、花叶症状的病毒样品,ELISA检测表明,该样品与黄瓜绿斑驳花叶病毒(Cucumber green mottle mosaic virus,CGMMV)有密切的血清学关系,利用RT-PCR方法从样品中扩增获得约500bp的DNA片段,序列分析表明,该片段是CGMMV的外壳蛋白基因,暂将该病毒分离物定名为GX-BG。外壳蛋白基因核苷酸序列系统进化树分析表明,已报道的CGMMV主要分为3大群体,GX-BG与中国辽宁分离物(CGMMV-LN)分别属于不同的群体。     

转cryAb基因克螟稻对水稻白叶枯病和纹枯病的抗性评价

转cryAb基因克螟稻对水稻白叶枯病、纹枯病的抗病性在田间进行了人工接种鉴定,根据亲本材料秀水11及2个转基因材料克螟稻1号(KMD1)和克螟稻2号(KMD2)的发病情况,初步明确两个转基因材料的抗病性与亲本存在显著的差异,对白叶枯病的抗性比亲本材料有所上升,但对纹枯病的抗性则不如亲本秀水11。     

大豆RSC4抗病候选基因Glyma.14G204700的克隆及其生物信息学分析

为明确大豆抗大豆花叶病毒（soybean mosaic virus，SMV）SC4株系的基因位点R_SC4（resistance to SMV strain SC4，R_SC4）的候选基因Glyma.14G204700在大豆不同抗性品种中的序列结构特征和保守结构域，以齐黄1号、科丰1号、大白麻和南农1138-2共4个大豆品种为材料，通过基因克隆获得大豆Glyma.14G204700基因的cDNA全长序列，并采用生物信息学方法分析其序列特征和编码蛋白的理化特性及结构特征。结果表明，大豆Glyma.14G204700基因在4个大豆品种中的cDNA全长为4 719~4 776 bp，编码1 295~1 307个氨基酸，预测蛋白的分子量为148.38~149.33 kD，等电点为5.53~5.61，均为具较强亲水性的非分泌蛋白。Glyma.14G204700蛋白含有植物抗病基因家族蛋白的保守功能域——核苷酸结合域和富含亮氨酸重复结构域。该蛋白的二级结构主要由α-螺旋、无规则卷曲、延伸链和β-折叠组成，所占比例分别为59.45%~61.08%、28.65%~30.15%、8.11%~8.88%和1.61%~2.16%。启动子序列分析发现该基因含有脱落酸、低温及干旱等多种逆境胁迫响应元件。表明大豆R_SC4抗病候选基因Glyma.14G204700在大豆不同抗性品种中具有不同的等位变异，优异等位变异的鉴定和开发可为抗SMV大豆育种提供基础材料。     

甘肃小麦白粉病抗源材料的筛选及抗病基因库的组建

2002-2005年,对收集到的30份已知抗白粉病基因载体品种在甘肃省的不同生态区进行了抗病性监测,结果表明:Pm1、Pm3 a、Pm3 b、Pm3 c、Pm3 f、Pm4 a、Pm5、Pm6、Pm7、Pm8、Pm17在田间抗病性丧失,失去利用价值;Pm2、Pm19、Pm4+8、Pm4、Pm5+6、Pm13在田间抗病性较低,不宜单独作为亲本利用;Pm1+2+9、Pm2+6、Pm2+mld、Pm2+talent、Pm4+2 x、Pm4 b、Pm4 b+5、Pm20、Pm21、Pmxbd在田间抗性表现良好,在今后的育种工作中应充分加以利用。同时经过4年抗病性监测,从省内外2 638份小麦品种(系)材料中筛选出了抗病性强、综合农艺性状优良的92R137、贵农21等优异材料10余份,初步组建了抗白粉病基因库。文中还对抗病基因现状和利用及今后如何避免由于抗源单一化带来的白粉病流行进行了初步探讨。     

利用酵母的Pac I基因获得抗类病毒转基因植物

文章简要介绍了类病毒复制和反义RNA、核酶、Pac I在类病毒上的作用重点 ,阐述了Pac I基因介导的广谱抗性的应用前景和存在问题     

Inheritance of Resistance to Colletotrichum acutatum in Fragaria x ananassa

ABSTRACT Anthracnose, caused by Colletotrichum acutatum, is a major disease of the octoploid cultivated strawberry, Fragaria x ananassa The inheritance of high and intermediate level plant resistances to C. acutatum, pathogenicity group 2, was investigated in an 8 x 8 factorial design. A single dominant gene (Rca2) controlled the high-level resistance, although minor genes may also contribute to resistance in cultivars such as Belrubi. The intermediate level of resistance was quantitative and controlled by minor genes. Analysis of 26 genotypes and cultivars from Fragaria spp. showed that the dominant gene was not rare in the germ plasm of F. x ananassa and that anthracnose resistance was also present in other species of Fragaria. These findings have important implications for anthracnose resistance breeding.     

Plant-derived enzyme inhibitors and lectins for resistance against plant-parasitic nematodes in transgenic crops

Due to increasing restrictions on the use of toxic and expensive nematicides, there is now a greater than ever need for crop cultivars that are resistant to plant-parasitic nematodes. Genetically engineered nematode resistance is not as well developed as other engineered traits but, even so, the first genetically modified plants with enhanced nematode resistance have been produced and tested. Plant-derived enzyme inhibitor and lectin genes are being evaluated for their ability to confer broad-spectrum nematode resistance in transgenic crop plants. Early indications are that these are likely to be effective. Gene pyramiding has potential to increase field durability and to widen the spectrum of nematodes controlled by any one transgenic line. © 1998 SCI.     

小麦持久抗条锈病品种Champlein的抗性遗传分析

小麦条锈病是小麦生产中最重要的病害,培育抗病品种是防治条锈病最经济、有效、安全的措施。‘Cham-plein’引自法国,对条锈菌生理小种表现良好持久抗性。为了明确其抗性遗传特点,以感病品种‘铭贤169’与其杂交、自交和回交获得了F1、F2、F3和BC1代,人工接种小麦条锈菌生理小种CY32,在温室和田间对‘Champlein’进行遗传分析。结果表明:苗期‘Champlein’对CY32的抗病性由1对显性基因控制;成株期‘Champlein’对CY32的抗病性由2对显性和1对隐性抗条锈病基因以互补方式控制;系谱分析表明基因可能来源于‘Vilmorin27’。     

Multigenic system controlling viral systemic infection determined by the interactions between Cucumber mosaic virus genes and quantitative trait loci of soybean cultivars

Soybean 'Harosoy' is resistant to Cucumber mosaic virus soybean strain C (CMV-SC) and susceptible to CMV-S strain D (CMV-SD). Using enzyme-linked immunosorbent assay and Northern hybridization, we characterized the Harosoy resistance and found that CMV-SC did not spread systemically but was restricted to the inoculated leaves in Harosoy. Harosoy resistance was not controlled by either a dominant or recessive single gene. To dissect this system controlling long-distance movement of CMV in soybean, we constructed infectious cDNA clones of CMV-SC and CMV-SD. Using these constructs and the chimeric RNAs, we demonstrated that two viral components were required for systemic infection by the virus. The region including the entire 2b gene and the 5' region of RNA3 (mainly the 5' untranslated region) together were required. By quantitative trait locus (QTL) analysis using an F(2) population and the F(3) families derived from Harosoy and susceptible 'Nemashirazu', we also showed that at least three QTLs affected systemic infection of CMV in soybean. Our study on Harosoy resistance to CMV-SC revealed an interesting mechanism, in which multiple host and viral genes coordinately controlled viral systemic infection.     

小麦条锈菌中国鉴别寄主洛夫林10和洛夫林13抗条锈性遗传研究

 洛夫林10和洛夫林13是中国小麦条锈菌重要鉴别寄主,为明确其抗条锈性遗传基础,本文采用常规杂交分析和等位性检测相结合的方法,将洛夫林10、洛夫林13分别与完全感病品种铭贤169杂交、自交和测交,获得各组合的正反交群体,在温室对其进行苗期抗性鉴定和统计分析,并分别与已知基因载体品系杂交和自交进行等位性检测。结果表明,洛夫林10对CYR17和CYR26的抗性分别由1对显性基因控制,属核遗传,洛夫林10抗CYR17和CYR26的基因与Moro、洛夫林13、K733所含的抗条锈病基因等位或紧密连锁;洛夫林13对CYR17和Su-1的抗性均由2对显性互补基因控制,对CYR26的抗性由1对显性和1对隐性重叠或独立基因控制,均属核遗传,洛夫林13抗CYR17、CYR26、Su-1的2对基因中有1对基因与Moro中的抗性基因等位或紧密连锁,抗CYR17的另1对基因与Hybrid46中的抗性基因等位或紧密连锁。表明洛夫林10和洛夫林13同含Yr9,洛夫林10的Yr9可能来源于无芒1号,洛夫林13的Yr9和另1对基因均来源于Skorospelka3B,未知基因可能位于6B或6A染色体上。     

Pathogenesis-related gene expression in rice is correlated with developmentally controlled Xa21-mediated resistance against Xanthomonas oryzae pv. oryzae

Disease resistance mediated by the resistance gene Xa21 is developmentally controlled in rice. We examined the relationship between Pathogenesis Related (PR) defense gene expression and Xa21-mediated developmental disease resistance induced by Xanthomonas oryzae pv. oryzae (Xoo). OsPR1a, OsPR1b, and OsPR1c genes were cloned and their induction was analyzed, in addition to the OsPR10a gene, at the juvenile and adult stages in response to a wildtype Xoo strain that induces a resistance response (incompatible interaction) and an isogenic mutant Xoo strain that does not (compatible interaction). We found that the adult stage leaves are more competent to express these OsPR1 genes and that the Xa21 locus is required for the highest levels of induction.     

QTL作图在植物数量抗病性遗传研究中的应用

 本文综述了近年来在植物数量抗病性遗传研究方面的进展及发展动态。列举了利用DNA分子标记定位和估计植物数量抗性座位或基因(QRL)的18个实例,从中归纳总结了控制植物数量抗病性的QRL数目、类别、效应及其基因与基因和基因与环境、植株生育期、病菌生理小种(或致病类型)间的互作关系。展望了QTL作图对复杂的数量抗病性的标记辅助选育和数量抗性基因图位克隆的发展前景。     

30个小麦新品系抗条锈病基因分析及成株期抗病性评价

 小麦条锈病是影响我国小麦生产的重要病害之一,利用抗病品种是控制小麦条锈病流行的最经济有效的措施。逐步澄清我国小麦品种抗病基因组成及特点是合理利用抗病品种的基础。     

Effect of rotation of canola (Brassica napus) cultivars with different complements of blackleg resistance genes on disease severity

Blackleg disease (phoma stem canker) caused by the fungus Leptosphaeria maculans is a major disease of canola (oilseed rape, Brassica napus) worldwide. Canola plants in pots were exposed to blackleg‐infested stubble of canola with different complements of resistance genes and then assessed for disease. Plant mortality was reduced when plants were exposed to stubble from a cultivar with a different complement of resistance genes compared to stubble of a cultivar with the same resistance gene. These findings were consistent with 7 years of field surveys, which showed that changes in selection pressure as a result of extensive sowing of cultivars with major‐gene resistance, termed ‘sylvestris resistance’, dramatically influenced the frequency of virulent isolates in the population towards particular resistance genes, and therefore disease severity. All these data were supported by PCR‐genotyping surveys of fungal populations whereby the frequency of virulence alleles of avirulence genes AvrLm1 and AvrLm4 changed significantly depending on the resistance gene present in the cultivar from which the isolates were cultured. This is the first example of a study showing that sowing of canola cultivars with different complements of resistance genes in subsequent years, i.e. rotation of resistance genes, minimizes disease pressure by manipulating fungal populations. This approach provides a valuable disease management strategy for canola growers and is likely to be applicable to other plant diseases.     

小麦条锈病抗病遗传及菌源基地基因布局研究进展

小麦条锈病是世界范围内严重影响小麦生产安全的重要病害。我国是世界上最大的小麦条锈病流行区,自成独立的流行体系。培育和种植抗病品种是防治病害最有效的措施。然而,小麦品种对条锈病的抗性常常由于病菌新小种的产生而丧失,这既是一个重大科学问题,也是一个亟待研究解决的生产实际问题。如何有效、合理地利用小麦的抗病性,植病学家和育种学家进行了一个多世纪的研究与探索,提出了各种理论与策略,开展了各种实践与探索。该文就小麦抗条锈病遗传及其基因布局研究进展进行综述,主要包括抗性鉴定评价、抗病基因发掘与利用、数量抗性位点定位、抗病基因克隆与功能解析、近等基因系创建与应用,以及抗源创制、抗病生态育种和大区基因布局等,并对深入开展抗条锈病基因发掘与利用和大区基因布局进行展望,以期为抗病育种和病害持续治理提供参考。