国内重要抗源品种水源11、水源92及Hybrid46抗条锈基因关系分析

小麦著名抗源品种水源11、水源92及Hybrid46在我国小麦抗病育种中发挥了重要作用,为了明确其抗锈 遗传规律,研究用条中29号及其弱株突变系CY29-mut3,分别接种这3个品种的双列杂交F2、F3代各株系幼苗。结果表明,水源11、水源92与Hybrid46所含抗条锈基因不同,而同来自朝鲜的品种水源11、水源92可能含相同的或完全连锁的抗条锈基因。水源92有3对基因抗中国条锈小种,且不同小种及细胞质对基因表达都有影响,水源92为父本时分别对CY29-mut3及条中29号小种有3对显性基因起抵抗作用（其中两对基因表现为累加作用）;而当水源92为母本时分别对CY29-mut3及条中29号小种有1对完全显性基因和两对隐性基因表达抗病作用。国际已知基因品种Hybrid46为母本时对CY29-mut3有两对基因起作用（可能是两对隐性基因,也可能是存在累加作用的两对显性基因）,而对CY-29小种有3对独立遗传的显性基因表达抗病作用。     

西科麦2028抗条锈性的遗传分析

西科麦2028是地理远缘小麦材料的杂交后代,具有突出的抗条锈病性能。为了解西科麦2028对小麦条锈病的抗性遗传规律,以西科麦2028和铭贤169的杂交群体为研究对象,采用我国目前小麦条锈菌流行小种CYR31、CYR32、CYR33、Su11-4对供试群体进行成株期接种,分析杂交后代的抗病性及分布情况。结果表明:西科麦2028对CYR31的抗病性由3对显性基因控制;对CYR32由2对显性和1对隐性基因控制;对CYR33由1对显性基因控制;对Su11-4由1对显性和1对隐性基因控制。     

陇南地区不同海拔区域内小麦条锈菌群体遗传多样性的分析

小麦条锈病是世界范围内小麦上最重要的流行性病害之一,可造成严重的产量损失。陇南地区是我国小麦条锈菌主要越夏易变区和新小种发源地,了解该地区不同海拔高度区域内条锈菌遗传多样性有重要意义。本研究采用TP-M13-SSR荧光标记技术对11个种群330个小麦条锈菌分离株基因组DNA进行了SSR标记分析。不同海拔区域的条锈菌遗传多样性有明显的差异,高山区的遗传多样性比较丰富,半山区次之,川道区相对比较低。不同生态区域内,小麦条锈菌群体遗传分化程度不同,高山区和半山区遗传分化程度大,基因流小,川道区群体遗传分化程度比较小,基因流大。来自不同海拔区域的菌系具有相同的基因型,这一结果从分子水平证明了在陇南地区小麦条锈菌在山区与川地之间存在广泛的菌源交流,可就地完成周年循环。     

条锈菌侵染过程中小麦叶片水分关系的变化

以条绣茵29号小种(CY-29)及其弱毒突变菌系(CY29-mut     

'陕麦139'受条锈菌抑制表达相关基因的分析

以‘条中32’接种前后的小麦抗条锈病种质‘陕麦139’幼苗叶片为材料,利用抑制消减杂交技术,构建了条锈菌接种48 h小麦抗病品种叶片的抑制表达SSH-cDNA文库,通过测序以了解条锈菌侵染后被抑制表达的相关基因。从构建的文库中随机选取48个阳性克隆,进行测序,经过序列拼接等,获得高质量EST序列34条(Gen-Bank序列号为EL930132-EL930165),序列比对分析表明其中31条EST序列与已知功能的基因序列同源性较高,主要涉及植物的能量代谢途径、膜转运、信号传导及核酸加工等方面的基因,包括光合系统Ⅱ抗性蛋白D1、碳酸酵素、线粒体磷酸盐转运子、苹果酸脱氢酶、过敏性诱导反应蛋白和rRNA核酸内切酶等相关基因。此外,获得未知功能的EST序列3条。研究表明,小麦在条锈病菌侵染初期,许多基因的正常表达调控受到影响,如能量代谢和寄主细胞结构木质化,阻止小麦抗病过敏性反应等。     

在条锈菌侵染早期小麦初生叶内多聚核糖体水平与蛋白质合成能力的变化

小麦初生叶接种条锈菌毒性生理小种（ＣＹ２９）及其弱毒突变菌系（ＣＹ２９－ｍｕｔ３）后,呈不亲和反应的寄主叶片可溶性蛋白质合成能力在接种后２４ｈ显著高于未接种对照,但其后逐渐降低,直至接近对照;而呈亲和性反应的寄主叶片可溶性蛋白质合成在侵染早期与对照相近,但与膜结合蛋白质在９６ｈ时大大高于对照。对接种叶中核糖体的密度梯度分析证实：呈不亲和反应寄主叶片游离多聚核糖体及亲和反应的寄主内与膜结合多聚核糖体均有特异性增加。上述结果表明寄主的抗病和感病反应均与蛋白质合成能力的变化有关。     

粗山羊草抗条锈病新基因YrY206遗传分析和微卫星 标记

从小麦野生近缘属——粗山羊草中挖掘小麦条锈病抗病基因, 拓展小麦抗病性的遗传基础。利用抗小麦条锈病与感小麦条锈病的粗山羊草间杂交, 从粗山羊草[Aegilops tauschii (Coss.) Schmal] Y206中鉴定出1个显性抗小麦条锈病基因, 暂定名为YrY206。应用分离群体分组法(Bulked segregant analysis, BSA)筛选到Wmc11a、Xgwm71c、Xgwm161和Xgwm183标记, 与该基因之间的遗传距离分别为4.0、3.3、1.5和9.3 cM。根据连锁标记所在小麦微卫星图谱的位置, YrY206被定位在3DS染色体上。分析基因所在染色体的位置、抗病性特征, 认为YrY206是一个新的抗小麦条锈病基因。     

种衣剂17号包衣对小麦条锈菌发育影响的超微结构研究

本研究采用电镜技术研究了种衣剂17号对小麦条锈菌发育的影响。观察结果表明,该种衣剂引起病菌和寄主细胞内发生了一系列变化。病菌菌丝和吸器内脂肪粒和液泡明显增加;菌丝壁和吸器壁呈不规则加厚;菌丝分枝处无隔膜产生或隔膜畸形;有的吸器母细胞产生的畸形入侵栓,大都不能穿透寄主细胞壁,初生吸器外间质内沉积有染色较深的物质,次生吸器可产生多个不规则分枝,但不能扩张膨大;菌丝外渗的物质可能引起寄主细胞的坏死;大多数受侵寄主细胞可分泌形成较大的胼胝质,有时寄主细胞分泌的物质可将吸器体完全包围起来。上述结果表明,种衣剂17号不仅可直接作用于条锈菌,而且也可通过影响寄主而间接地影响病菌。     

低聚糖诱导小麦抗条锈性及相关酶活性变化的研究

用自行设计的方法从植物细胞壁中得到的低聚糖提取物5号对小麦浸种和苗期喷雾处理,均使接种条锈菌的小麦叶片产生了明显的过敏性坏死反应。对几种与抗病性密切相关的酶活性变化的分析表明,经低聚糖预先处理能显著提高小麦叶片的过氧化物酶(POD)、多酚氧化酶(PPO)和苯丙氨基酸解氨酶(PAL)的活性。     

Genetic research as the valid base of strategies for breeding rust resistant wheats

It is known that few wheat cultivars maintain their resistance to rust diseases for a long period of time, particularly when crop populations become genetically more uniform. A number of genetically diverse, so far unexploited, sources of rust resistance in the natural as well as mutagenized population of wheat cultivars were identified. Several of these genes were placed in agronomically superior well-adapted backgrounds so that they could be used as pre-breeding stocks for introducing genetic diversity for resistance in a crop population. Some of these stocks when employed as parents in several cross combinations in a breeding programme have generated a number of promising cultivars with diversity for resistance.Many presently grown wheats in India, near-isogenic lines each with Lr14b, Lr14ab, Lr30 and certain international cultivars were identified as possessing diverse sources of adult plant resistance (APR) to leaf rust. Prolonged leaf rust resistance in some of the Indian cultivars was attributed to the likely presence of Lr34 either alone or in combination with other APR components. Tests of allelism carried out in certain cultivars that continue to show adequate levels of field resistance confirm the presence of Lr34, which explains the role that this gene has played in imparting durability for resistance to leaf rust. Also, Lr34 in combination with other APR components increases the levels of resistance, which suggests that combination of certain APR components should be another important strategy for breeding cultivars conferring durable and adequate levels of resistance. A new adult plant leaf rust resistance source that seems to be associated with durability in Arjun has been postulated. Likewise, cultivars possessing Sr2 in combination with certain other specific genes have maintained resistance to stem rust.Further, non-specific resistances that were transferred across widely different genotypes into two of the popular Indian wheats provided easily usable materials to the national breeding programmes for imparting durable resistance to stripe rust.     

另辟蹊径破解小麦条锈病的基因密码

小麦条锈病是由条形柄锈菌小麦专化型(Puccinia striiformis f. sp. tritici, Pst)引起的真菌病害,在全世界范围内危害小麦(Triticumaestivum)生产。培育和种植持久抗性小麦品种是控制小麦条锈病最有效的方法。由于病原体突变导致免疫受体逃避检测,因此抗病基因经常失效。而易感基因(S基因)突变介导的抗性常具持久性与广谱性。近日,西北农林科技大学植物免疫研究团队在揭示小麦受S基因保护的分子机制方面取得显著进展,为抗病育种提供了有力工具。他们发现小麦感染条锈菌后,真菌诱导受体样细胞质激酶TaPsIPK1与效应子PsSpg1特异性互作,通过增强激酶活性和TaPsIPK1进入细胞核促进寄生。TaPsIPK1磷酸化转录因子TaCBF1d。TaCBF1d的磷酸化改变了其下游基因的转录活性。因此, TaPsIPK1和PsSpg1增强TaCBF1d磷酸化可能会重新编程靶基因表达,干扰植物防御反应,从而促进病原体感染。在2年的田间试验中,小麦中TaPsIPK1的CRISPR-Cas9失活赋予了对Pst的广谱抗性,且不影响重要的农艺性状。该研究首次揭示了由PsSp...     

Backcross-breeding and doubled-haploid facilitated introgression of stripe rust resistance in bread wheat

Stripe rust caused by the fungus Puccinia striiformis f. sp. tritici (Pst) may decrease wheat yield significantly in severe outbreaks. The most cost-effective and environmentally friendly approach to reduce yield losses due to rust diseases is deployment of effective resistant genes in wheat cultivars. The causal agents evolve and may break existing resistant sources as well. Therefore, long-term conventional breeding strategies and the ongoing evolution of pathogen populations in the region would put the success of breeding programmes at risk so that there is always a need for speeding up the process of germplasm enhancement through production of doubled-haploid breeding materials. In this study, we aimed at introgression of stripe rust resistance trait from three genotypes (Flanders, Martonvasar-17 (MV17) and Bersee) into a widely adapted cultivar “Ghods”. Positively selected F2BC² progenies of three backcrossing schemas, i.e. (i) Flanders/3^*Ghods; (ii) Ghods^*3/MV17; and (iii) Hybride-de-bersee/3^*Ghods, were used to produce three small-size doubled-haploid populations via wheat × Maize pollination methodology. The doubled-haploid populations were examined against two predominantly isolates of P. striiformis f. sp. tritici (Pst) i.e. 6E134A⁺ and 6E2A⁺Yr27⁺ and the screening revealed that 44 and 52 of the progenies are resistant to the above-mentioned isolates, respectively. Field data have shown that the stripe rust resistance doubled-haploid germplasm are comparable to local check cultivars in yield and earliness.     

条锈菌诱导的抗锈小麦种质的基因表达分析

以条锈菌接种前后的抗条锈病种质N 95175的小麦幼苗叶片为材料,利用抑制消减杂交技术,构建了条锈菌接种初期小麦抗性种质叶片的SSH-cDNA文库。通过对文库中随机选取的50个阳性克隆提取质粒,进行测序,共获得已知功能的EST序列14条,如蛋白激酶、锌指蛋白、细胞色素P 450和OM T 1等抗病相关基因,它们涉及植物的信号传导、转录调控、丙烷代谢途径及防卫反应等方面。     

DNA分子标记在小麦抗条锈性遗传研究中的应用

综述了近年来DNA分子标记在小麦抗条锈性遗传研究中的应用现状和潜力。内容涉及DNA分子标记在基因标记,基因克隆,遗传图谱构建和辅助选择育种等方面的应用,并列举了代表性实例,展望了DNA分子标记技术在小麦抗条锈病研究上的前景。     

小麦背景中来自华山新麦草的抗条锈病基因的遗传学分析和分子标记

H9020—17—5是一个通过杂交和回交选育的普通小麦—华山新麦草易位系,接种鉴定表明其对条锈病具有优良抗性。遗传学分析证明易位系H9020—17—5的抗条锈性是由单基因控制的显性性状,抗性基因来自于华山新麦草,暂定名为YrHua。为了标记这个来自华山新麦草的抗条锈病基因,利用H9020—17—5与感病小麦品种铭贤169杂交,建立了F2分离群体。应用81对AFLP引物对119个经条锈菌生理小种CY30接种鉴定的F2单株进行了分析,结果得到两个与YrHua基因连锁的AFLP标记PM14(301)和PM42(249),遗传距离分别为5．4cM和2．7cM,并分别位于目标基因的两侧。将标记片段克隆、测序后,根据序列信息和酶切位点多态性设计特异性引物,将AFLP标记PM14(301)转换成了简单的PCR标记。研究结果为标记辅助育种提供了分子选择工具,同时也为进一步精细定位和图位克隆YrHua基因奠定了基础。     

小麦品种贵农22号抗条锈基因遗传分析

贵农22号是利用簇毛麦(Haynaldia villosa)、硬粒小麦(Triticum durum)及普通小麦(Triticum aestuvum)杂交而育成的普通小麦品种,其抗中国目前流行和出现的条锈菌小种,已成为目前重要的抗小麦条锈病抗源。为了明确该品种抗锈遗传规律并进行应用前景评价,用一个流行的强毒性小种条中31号和一个突变弱毒性小种CY29-mut3,分别接种贵农22与国际已知抗锈基因品种Moro及感病品种辉县红双列杂交F2、F2代各株系幼苗,对贵农22号进行了抗锈性遗传分析,以便于在抗病育种中进一步应用。研究结果表明,贵农22号有三对独立遗传的抗条锈基因,暂定名为YrGui 1、YrGui 2和YrGui 3,它们表达稳定,不受亲本正反交影响,而并不具有Yr 10。Yr10基因载体品种Moto中有二或四对基因抗中国不同的条锈菌小种,不同小种及正反交对基因的表达有影响,为父本时其对CY29-mut3小种有两对完全显性基因、一对中度抗病基因及一对隐性抗病基因,而为母本时有一对完全显性基因和一对中度抗病基因起抗病作用;对条中31号,其为父本时有一对显性基因和一对隐性基因,为母本时可能存在两对累加作用基因或两对隐性抗病基因控制抗痫作用。     

The genetic of pathogenicity of Puccinia striiformis f. sp. tritici the cause’s agent of wheat yellow rust disease in Iran

Wheat yellow (stripe) rust disease is one of the important and prevalent diseases of wheat in the world. In this study, 37 isolates of yellow rust diseased from most important wheat-growing areas in Iran has been collected, and the genetic of pathogenesis and race analysis as well as abundance per cent of the disease for genes under study with using 45 differential and isogenic lines together with susceptible Bolani were applied. The experimental materials with the spores of each isolate that were inoculated in the seedling stage separately and after 17?days scored by McNeal et al. method. Also the physiologic races responsible for the disease determined according to Johnson and his colleagues method. The results showed that the race 166E254A?+?Yr27+ with 62.50% of pathogenesis was the most aggressive race from Torogh (Mashhad) 6, and the race 6E134A+ with 33.34% of pathogenesis factor was the weak race from Zarghan1. According to these results, for all the plants containing genes Yr2, Yr6, Yr7, Yr9, Yr18, YrA virulence was observed from all isolates. For the plants contained with genes Yr1, Yr4, Yr5, Yr10, Yr15, YrSU were effective against all isolates. Genes Yr3, Yr24, YrSP with low per cent of pathogenesis (2.7) and genes Yr2, Yr6, Yr7, Yr9, Yr18, Yr4 with high per cent (100) and Yr17 (97.3) have been identified.