普通小麦抗条锈新种质—体克2号的抗性遗传分析

对普通小麦抗条锈新种质—体克2号进行了遗传学分析和RAPD标记研究。结果表明,体克2号对条中32号生理小种的的抗性是由1对显性基因控制的。RAPD分析筛选出重复性强、在抗病亲本和抗性基因池稳定出现的特异DNA片段2个,即引物S369的扩增片段和引物S1397的扩增片段,其长度分别约为770bp和1400bp。利用Mapmaker3.0对引物S369扩增出来的特异片段与目的基因的遗传连锁性进行分析,该多态性差异与目的基因的连锁距离为10.4cM。     

SSR and STS markers for wheat stripe rust resistance gene <Emphasis Type="Italic">Yr26</Emphasis>

Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating wheat diseases worldwide. Triticum aestivum-Haynaldia villosa 6VS/6AL translocation lines carrying the Yr26 gene on chromosome 1B, are resistant to most races of Pst used in virulence tests. In order to better utilize Yr26 for wheat improvement, we attempted to screen SSR and EST-based STS markers closely linked with Yr26. A total of 500 F₂ plants and the F_2:3 progenies derived from a cross between 92R137 and susceptible cultivar Yangmai 5 were inoculated with race CYR32. The analysis confirmed that stripe rust resistance was controlled by a single dominant gene, Yr26. Among 35 pairs of genomic SSR markers and 81 pairs of STS markers derived from EST sequences located on chromosome 1B, Yr26 was flanked by 5 SSR and 7 STS markers. The markers were mapped in deletion bins using CS aneuploid and deletion lines. The closest flanking marker loci, Xwe173 and Xbarc181, mapped in 1BL and the genetic distances from Yr26 were 1.4 cM and 6.7 cM, respectively. Some of these markers were previously reported on 1BS. Eight common wheat cultivars and lines developed from the T. aestivum-H. villosa 6VS/6AL translocation lines by different research groups were tested for presence of the markers. Five lines with Yr26 carried the flanking markers whereas three lines without Yr26 did not. The results indicated that the flanking markers should be useful in marker-assisted selection for incorporating Yr26 into wheat cultivars.     

陕农78抗条锈性遗传规律分析

通过对抗条锈病品种陕农78与感病品种铭贤169 杂交获得的F1代、F1代自交获得的F2代、及F1与铭贤169回交获得的BC1代植株,在人工控制条件下,利用条锈病菌优势生理小种条中31、条中32对苗期进行人工接种后的反应型分析认为：陕农78对条中31的抗性是由1对隐性基因所控制;陕农78对条中32的抗性是由2对隐性基因互作所控制。     

水稻抗纹枯病QTL qSB-9TQ和抗条纹叶枯病基因Stv-bi的聚合育种

以携带抗纹枯病QTL qSB-9^TQ的籼稻品种特青和携带抗条纹叶枯病基因Stv-bⁱ的粳稻品种镇稻88为优良等位基因供体亲本,江苏省推广的粳稻品种武育粳3号和武粳15为受体亲本,分别杂交并连续回交。在回交及自交分离世代,利用开发的覆盖目标基因区间的双侧分子标记对目标基因进行辅助选择。至回交BC₄F₁世代,同一遗传背景2个回交方向的中选单株间聚合杂交,获得2个目标基因位点均纯合的聚合F₃株系。条纹叶枯病抗性鉴定和纹枯病抗性接种鉴定结果表明,聚合株系对条纹叶枯病均表现抗病;以0~9级评级标准评价,聚合株系的纹枯病较相应的轮回亲本分别低1.1~1.6级和0.8~1.4级。结合回交低世代抗性鉴定结果分析,自行开发的分子标记对目标基因的辅助选择是有效的。讨论了抗纹枯病育种及分子标记辅助选择聚合育种的相关问题。     

水稻条斑花叶突变体生态st(t) 的鉴定与遗传定位

利用EMS诱变育成优良籼型恢复系缙恢10号,从其后代中鉴定出一个白色条斑花叶突变体st(t),在三叶期开始表现白斑,拔节期白斑变为不规则线状,一直保持到成熟。突变体叶绿素含量明显下降,类胡萝卜素含量显著升高。透射电镜观察表明,突变体的绿色叶片部位与野生型相比,在细胞结构上无明显差异,叶绿体发育正常;突变体的白化部位细胞结构异常,质体内多含有积聚在一起的嗜锇小球,不能发育出正常叶绿体所具有的类囊体和基质片层结构。遗传分析表明该性状受一对隐性核基因调控,利用1 500株西农1A/st(t)的F₂隐性定位群体,最终把St(t)基因定位在第6染色体SSR标记RM19745和RM19762之间,遗传距离分别为0.07 cM和0.27 cM,根据9311基因组序列推测,两标记之间的物理距离约为345 kb。这为St(t)基因的图位克隆和分子标记辅助育种奠定了基础。     

The development of a PCR-based method for detecting <Emphasis Type="Italic">Puccinia striiformis</Emphasis> latent infections in wheat leaves

Stripe rust of wheat caused by Puccinia striiformis f. sp. tritici is one of the most important diseases on wheat worldwide, especially in temperate regions with cool moist weather conditions. A rapid and reliable detection of the pathogen in latent infected wheat leaves during overwintering of the fungus in the dormant stage will contribute to determine the initial inoculum potential and thus to predict early outbreak and to improve effective management of the disease. To achieve this aim, a PCR-based method was developed for specific and sensitive detection of P. striiformis. Specific primers were designed according to a genome-specific sequence of P. striiformis. To evaluate the specificity of the primers, seven different isolates and races of P. striiformis as well as six other pathogens of wheat were tested. All isolates of P. striiformis yielded a distinct band of a fragment of 470 bp, while using DNA of the other wheat pathogens as a template no amplification product was detected. The sensitivity of the primers was tested using serial dilutions of total DNA from P. striiformis; the limit of detection was 10 pg of DNA. Using extracts from P. striiformis-infected wheat leaves, the fungus could be determined in the leaves before symptoms appeared. The stripe rust could also be detected in the dormant stage by the PCR assay in samples of wheat leaves taken during the winter season. The application of the PCR assay may be useful for rapid and reliable detection of P. striiformis in latent infected leaves of overwintering wheat plants.     

气象条件对甘肃冬小麦条锈病流行的影响研究

应用积分回归的方法分析了甘肃省东部地区气候条件对条锈病发生、发展的影响。结果表明：气温的影响在中部和北部以负效应为主，南部以正效应为主；降水、相对湿度的正效应十分明显，且影响效应大于温度。总体而言，甘肃东部的气候环境有利于小麦病虫害的发生发展。     

基于Fraunhofer线的小麦条锈病荧光遥感探测

【目的】遥感监测小麦条锈病比传统调查方法更省时、省力并能实现大范围实时监测。【方法】田间人工诱发产生不同发病等级的小麦条锈病群体，采用ASD光谱仪的Radiance方式对其冠层光谱进行了测定。通过比较目标和参考板太阳光谱中两个氧吸收波段的Fraunhofer线深，计算植株发射的叶绿素荧光。【结果】760 nm处叶绿素荧光与病情指数高度负相关，688 nm处叶绿素荧光与病情指数高度正相关。并且随着病情指数的升高，作为反映植物胁迫状态的荧光比值指标F688/F760亦随之增大。另外对单叶相关光合指标测试结果表明，随着病叶严重度水平的升高，SPAD、荧光参数Fv/Fm和Yield以及净光合速率均有不同程度的下降。【结论】利用Fraunhofer线原理提取的日光诱导荧光信息可以反映田间小麦条锈病的发病状况，为病害的遥感监测提供了又一途径。     

CBERS-02影像条带噪声处理方法探讨

选择覆盖内蒙古阿荣旗地区CBERS02-CCD数据,采用直方图匹配法、主成分分析法、矩匹配法、低通滤波法、小波变换法等空间域和频率域共5种方法,结合定性分析和定量计算对比评价,结果表明,小波变换法可以有效去除条带噪声,而且在细节突出方面也存在一定优势;矩匹配法容易改变地物本身的光谱信息,虽然条带去除效果较好,但不适宜CBERS-02影像数据图像与处理工作;主成分分析法不仅没有去除条带,在某种程度上,反而加强了条带噪声。     

水稻抗条纹叶枯病基因Stv-bi的分子标记辅助选择

水稻条纹叶枯病是我国黄淮及长江流域粳稻区重要的病害。由于水稻条纹叶枯病的发病受外界条件影响较大,人工接种抗性鉴定比较困难,利用与抗病基因紧密连锁的分子标记进行标记辅助选择对提高抗性育种效率具有重要意义。来自籼稻抗源Modan的Stv-bⁱ是水稻育种中广泛应用的条纹叶枯病抗性基因。本研究设计了与Stv-bⁱ紧密连锁的SSR及STS分子标记,用3个抗条纹叶枯病混合群体F30718(圣稻13/镇稻88)、F50701(武优34/T022//圣稻806)、F60702 (V6/T022//镇稻88)进行分子标记检测和田间条纹叶枯病抗性鉴定,其结果的符合率分别为99.3%、87.7%和91.8%。表明这些分子标记可以用于条纹叶枯病抗性基因Stv-bⁱ分子标记辅助选择。