【作者】 宋伟；

【导师】 张敏；

【作者基本信息】 四川农业大学 ， 植物病理学， 2010， 硕士

【摘要】 小麦白粉病和赤霉病是小麦生产上的两大重要病害。近年来,在我国的西南地区,随着灌溉水平的提高以及氮肥的大量施用,小麦白粉病和赤霉病危害日益严重,因此防治这两种病害也变得更加重要。化学防治这两种病害虽然取得了一定的成效,但需花费大量人力、物力、财力,而且还会引起环境污染等生态问题。因此培育和推广抗病品种被公认为是防治小麦白粉病和赤霉病最经济、有效、安全的途径。通过杂交或转基因技术培育出即高抗白粉病,又对赤霉病具有较好抗性,且综合性状也较好的新材料、新品种对于防治这两种病害具有重要意义。本研究通过将抗赤霉病的小麦品系苏麦3号与抗白粉病的小麦品种内麦9号(含抗白粉病基因Pm21)进行杂交,利用抗白粉病基因Pm21的SCAR特异标记和覆盖苏麦3号抗赤霉病主效QTL(Qfhs. ndsu-3BS)的4个SSR标记(Xgwm493、Xgwm533、Xgwm389和Xbarc87)在F2代进行分子标记辅助选择,并结合田间白粉病和赤霉病的抗病性鉴定,以期筛选对小麦白粉病免疫(含抗白粉病基因Pm21),且携带有苏麦3号的抗赤霉病基因的聚合体,该聚合体可能成为小麦育种的优良新材料。对203株F2代群体进行田间抗病性鉴定,鉴定结果如下。白粉病抗病性鉴定结果表明：138株抗白粉病,抗病株表现出免疫至高抗,与内麦9号抗病性表现一致；65株感白粉病,感病株表现出高感,未发现中抗至中感的中间型抗病性表现的单株；赤霉病抗病性鉴定结果表明：感病对照绵阳31号平均病小穗率为48.27%,严重度3～5级；内麦9号平均病小穗率为41.27%,严重度3～5级；抗病对照苏麦3号平均病小穗率为14.75%,严重度1～2级。F2代203个单株中病小穗率为0～10%的有40个单株,严重度1～2级,占20%,初步认为抗病性与苏麦3号相当；小穗率为10～25%的有55个单株,严重度2级,占27%,小穗率为25～50%的有51个单株,严重度3级,占25%,小穗率为50～75%的有28个单株,严重度4级占14%,小穗率为75～100%的有29个单株,严重度5级,占14%。其中病小穗率小于25%(严重度1～2级)的单株有95株,视为抗病株,其余的108株病小穗率大于25%视为感病株。综合两种病害的鉴定结果来看：41个单株对白粉病高抗至免疫且对赤霉病抗性与苏麦3号相当,初步作为筛选到得的双抗单株,再利用分子标记检测其抗病基因。分子标记检测结果：抗白粉病基因Pm21的特异SCAR标记检测这41株双抗单株均能扩增出一条约1400bp的特异条带,而感病单株未扩增出该条带；利用覆盖苏麦3号3BS染色体上抗赤霉病主效QTL的4个SSR标记对初选到得41个双抗单株进行PCR扩增,结果表明其中的12个单株能扩增出扩增出Xgwm493(210bp). Xgwm533(140bp).Xgwm389(130bp)和Xbarc87(100bp)Qfhs.Ndsu-3BS特异目标片段,其余单株只能扩增出4个标记中的1～3个。本研究经过田间抗病性鉴定的初选以及分子标记检测复选,在F2代中成功筛选到12株小麦单株,其既携带抗白粉病基因Pm21,又含有苏麦3号3BS上抗赤霉病主效QTL的小麦植株,对白粉病和赤霉病皆具有良好的抗性,而且含有内麦9号的大量优良基因,其农艺性状明显优于苏麦3号,因此可作为多抗优质育种的中间材料,有望在此基础上培育出优良品种。更多还原

【Abstract】 Powdery mildew and Fusarium head blight (FHB) are two important diseases in wheat. In recent years, China’s southwest region, with irrigation levels and the large number of nitrogen fertilizer, wheat powdery mildew and FHB damage are growing, so the fighting against both diseases is becoming more important. Although chemical control of these two diseases has made certain achievements, but it took a lot of manpower, material and financial resources, but also caused environmental pollution and ecological problems. Therefore, cultivation and promotion of resistant cultivars was recognized as against wheat powdery mildew and FHB the most economical, effective and safe way. By hybrid or genetically modified that was highly resistant to powdery mildew, it also has good resistance to FHB, and the characters were better integrated new materials, new varieties of disease for both prevention and treatment was important.In this study, Sumai 3, a resistant wheat variety to FHB, was crossed with Neimai 9, a wheat commercial cultivar with the resistance to powdery mildew. The SCAR(sequence characterized amplified region)markers of powdery mildew resistance gene Pm21 and four SSR (simple sequence repeats) markers (Xgwm493, Xgwm533, Xgwm389 and Xbarc87) covering the major FHB resistance QTL (Qfhs. ndsu-3BS) in Sumai 3 were used to detect the resistance loci by marker assisted selection (MAS) in the plants of the F2 population, combined with powdery mildew and FHB in the field Identification of disease resistance to wheat powdery mildew and FHB. It is want to obtain some plants out of the population with resistance to wheat powdery mildew(including powdery mildew resistance gene Pm21) and FHB (including FHB resistance gene form Sumai 3).The plants perhaps are excellent new parental materials for wheat breeding.The results showed that resistance in field identification:in the 203 plants of the F2 population, the powdery mildew resistance identification results showed that: 138 plants were resistant to powdery mildew, and they showed high resistance to immunization, and they showed the same resistance to Neimai 9; 65 plants susceptible to powdery mildew, they showed high sense, not found in the anti-sense intermediate between the performance of plant disease resistance. Identification of FHB resistance showed that:average spikelet disease rate of Mianyang 31 was 48.27%, the severity of 3 to 5; average spikelet disease rate of Neimai 9 was 41.27%, the severity of 3 to 5; resistant control Sumai 3, the average spikelet disease rate was 14.75%, the severity of 1 to 2. Hybrid plant in the F2 generation of 203 patients was 0～10% of the spikelets were 40 plant and severity of 1 to 2, accounting for 20% of the preliminary view that Sumai 3 resistance and considerable; spikelet disease rate of 55 plant was 10～25%, severity level 2, accounting for 27%; spikelet disease rate of 51 plant was 25～50%, and severity level 3, accounting for 25%; spikelet disease rate of 28 plant was 50～75%,, severity level 4, accounting for 14%, spikelet disease rate of 29 plant was 75～100%, severity level 5, accounting for 14%. Spikelet disease rate among patients less than 25%(severity of 1～2)of the plant with 95, as resistant strains of the remaining 108 patients greater than 25% of the spike rate as a sense of strain. On the whole there were 41 individual plants with high resistance to powdery mildew and FHB immune and Sumai 3 very preliminary, as screened, double anti-plant, then resistance genes using molecular markers.Marker test results:powdery mildew resistance gene Pm21 in specific SCAR markers that 41 pairs of monoclonal anti-treaty could amplify a 1400bp specific band, while the plant was not susceptible amplified this band; using covering Sumai 3 chromosome 3BS FHB resistance QTL main effects of the four SSR markers were 41 pairs of primary resistance to plant for PCR amplification, the results showed that 12 of them could be amplified plant expansion the Xgwm493(210bp), Xgwm533(140bp), Xgwm389 (130bp) and Xbarc87(100bp) Qfhs. Ndsu-3BS specific target fragment, the remaining plant only four markers were amplified in 1 to 3.After this study, the primary field identification of disease resistance and molecular markers check, successfully screened in the F2 generation to 12 while carrying powdery mildew resistance gene Pm21, then with Sumai 3 on 3BS FHB resistance QTL main effect wheat plants, and within the wheat with a large number of excellent genes Neimai 9, its agronomic traits superior to Sumai 3. Therefore, they can be used as much quality and resistance breeding in the middle of materials on this basis is expected to breed improved varieties.更多还原