小麦赤霉病抗病机制研究进展

小麦赤霉病是一种小麦穗部病害,严重影响小麦的产量和品质。挖掘小麦赤霉病抗性基因,揭示其抗病机制,对于提高小麦赤霉病抗性,推动小麦赤霉病抗性育种进程具有重要的意义。系统阐述了抗赤霉病相关QTL、多组学研究、细胞壁防卫、信号转导、次生代谢物合成、识别应答等小麦赤霉病抗性机制的研究进展,并对未来小麦赤霉病抗性机制的研究方向进行了探讨。希望以此加深研究者对小麦赤霉病抗性机制的了解,为未来小麦抗赤霉病分子机制研究提供理论基础,为小麦抗赤霉病遗传改良提供丰富的基因资源。     

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。     

普通菜豆基因组学及抗炭疽病遗传研究进展

普通菜豆是重要的食用豆类之一,在世界各大洲普遍种植。近年来,普通菜豆在遗传图谱构建、新标记开发与利用、抗性基因定位以及比较基因组学等方面取得了很大进展。遗传连锁图谱的构建是基因定位与克隆的基础,是遗传研究中的重要内容;利用分子连锁图谱鉴定、标记和定位抗病基因将在种质改良和分子标记辅助育种方面发挥重要作用。豆科植物比较基因组学的研究成果为菜豆遗传连锁图谱的发展提供了新的思路。本文从普通菜豆遗传连锁图谱的获得、普通菜豆与大豆同线性比较以及抗炭疽病基因定位等方面进行了综述,以期为普通菜豆遗传改良和抗病育种提供参考。 关键词：普通菜豆;遗传连锁图;同线性比较;抗菜豆炭疽病     

小麦高分子量麦谷蛋白亚基鉴定及其品质效应研究进展

高分子量谷蛋白亚基(HMW-GS,high molecular weight glutenin subunits)是小麦子粒贮藏蛋白的重要组成成分,其组成、搭配、表达水平及含量决定面团弹性和面包加工品质。本文主要介绍了小麦HMW-GS编码基因的克隆、分子特征、分子标记开发及其在小麦育种中的应用,并综述了不同HMW-GS与面粉加工品质之间的关系,以及HMW-GS基因遗传转化、微量配粉和突变体培育等方面的研究进展,分析了目前研究中存在的主要问题,认为通过分子标记辅助选择和转基因技术聚合优质亚基,培育优质面包小麦品种和明确各个HMW-GS基因的品质效应是今后的研究重点。     

PCR-RAPD分子生物学技术及其在植物抗病性研究中的应用

PCR—RAPD技术是一种高效的基因组DNA多态性分析技术,能够在对生物细胞或组织中DNA遗传多样性、亲缘关系及系统进化分子标记检测的同时进行基因定位与遗传作图。本综述了PCR—RAPD技术的基本原理和应用范围,以及近年来在植物抗感病品种(品系)间亲缘远近关系分析、植物抗病性遗传基因的DNA分子标记与检测、植物抗病基因的标记和定位、植物抗病基因的分离与克隆、植物抗病育种的分子标记辅助选择与检测等植物抗病性分子机制研究方面的应用,并对该技术所存在的问题及应用前景进行了探讨。     

小麦梭条花叶病抗性遗传和育种研究进展

由土壤真菌禾谷多粘菌(Polymyxa graminis)传播的小麦梭条花叶病在我国长江流域和黄淮平原麦区已成为危害小麦生产的一种严重病害。本文系统地综述了我国在小麦梭条花叶病种质资源筛选、抗性机理、抗性遗传、抗病基因的分子标记以及抗病育种方面的进展。研究表明,在我国地方品种和改良品种中存在着较丰富的抗病资源;植物体内某些酶的活性和可溶性糖含量与抗性有密切的联系;抗病性表现为数量性状的遗传特征,可能受1~3对显性基因控制。通过抗感品种间杂交,可以育成抗病丰产的新品种。文中还对今后开展小麦抗梭条花叶病育种提出了几点建议。     

我国“十三五”育成小麦新品种（系）抗赤霉病进展分析与展望

小麦赤霉病严重威胁我国粮食和食品安全,培育抗赤霉病小麦品种是解决该病害最经济有效的途径。20世纪90年代后,以扬麦158为代表的扬麦、宁麦系列中抗赤霉病品种的育成和大面积推广有效抵御了长江中下游麦区的赤霉病危害,使我国抗赤霉病育种处于国际领先水平。尽管全球明确了7个抗赤霉病基因,为开展抗赤霉病育种提供了重要支撑,但由于赤霉病抗性机制复杂,实现高抗与高产的协调仍极其困难,抗赤霉病仍是当前及未来我国小麦育种的主要目标。对“十三五”期间我国小麦新品系和审定品种的抗性情况以及我国抗赤霉病育种方面取得的进展进行了综述,并提出了重视挖掘和利用扬麦等推广品种中优异抗性基因、将Fhb1导入扬麦等主栽品种的育种技术路线和重视表型精准鉴定等建议,以期为实现我国抗赤霉病育种突破提供借鉴。     

分子标记在绿豆遗传连锁图谱构建和基因定位研究中的应用

绿豆(Vigna radiata(L.)Wilczek)作为一种医食两用作物,不仅是重要的食物资源,在改善土壤环境、提高农民收入等方面也发挥着重要作用。然而,相对于大宗作物而言,绿豆基础研究薄弱,基因组研究更是落后。近年来,分子标记技术迅速发展,在绿豆基因组学研究中发挥了重要的作用。国内外利用分子标记技术已构建了超过20张绿豆遗传连锁图谱。一些优良基因尤其是与抗性相关的基因被鉴定或精细定位,为绿豆分子标记辅助选择打下基础,加快了抗性新品种的培育进程。本研究通过对分子标记技术在绿豆遗传连锁图谱构建、重要功能基因的定位等方面的应用进行综述,以期为绿豆遗传育种研究及功能基因组学分析提供参考。     

栽培小麦Brock中与新抗白粉病基因紧密连锁的AFLP分子标记筛选与分析

本研究用225对引物对农艺性状优良但对白粉菌敏感的栽培小麦京411、抗白粉病栽培小麦Brock以及京411与Brock配制的近等基因系进行AFLP分子标记筛选,结果发现只有2对引物组合Pst GAC/Mse TCT(P1)和Pst AGC/Mse ACC(P2)在上述抗感材料中表现出多态性,分别扩增到2个特异片段,将特异片段克隆并测序发现,P1扩增的特异片段长268bp,P2扩增的特异片段长227bp,命名为AFLP标记P1268和P227.用106个京411×Brock的F2单株进行连锁性分析表明,P1268和P2227与抗白粉病基因的遗传距离分别为3.6和1.9cM,与Brock中的抗白粉病基因呈紧密连锁.该两个AFLP标记对小麦抗白粉病基因的积累和分子标记辅助选择育种有重要意义.     

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。     

小麦赤霉病新抗源的发掘与抗性位点的检测分析

小麦赤霉病是由禾谷镰刀菌引起的世界性重要病害,发掘优异的抗性种质资源、培育抗病品种是持续防治赤霉病最经济且环境友好的措施。为发掘新的赤霉病抗源,本研究于2017—2021年在弥雾保湿大棚中,采用单花滴注法对642份小麦种质资源的赤霉病抗扩展性进行鉴定,同时利用已知抗赤霉病基因/位点Fhb1~Fhb7的分子标记对筛选出的抗性种质基因型进行分析。结果表明,不同年份间赤霉病病小穗率的相关性均达到极显著水平。筛选到3年及以上赤霉病抗性优于扬麦158的种质81份,主要来自长江中下游麦区,其中33份种质连续4年抗性优于扬麦158;筛选到3年及以上抗性与苏麦3号相当的种质9份,分别为望水白、Grandin、浩麦1号、剑子麦、魁小麦、农林26、软秆洋麦、苏麦2号和武农6号,其中剑子麦、软秆洋麦、苏麦2号和Grandin连续4年抗性与苏麦3号相当。对抗性种质携带的抗赤霉病基因/位点进行分析发现,浩麦1号、冀师7225-28、南农13Y110、石优17和武农6号不携带任何已知抗赤霉病基因/QTL,为小麦抗赤霉病研究和品种培育提供了新的种质资源和理论依据。     

小麦抗赤霉病外源种质的创制和育种利用

小麦赤霉病是危害小麦安全生产的重要病害之一,种植抗病品种是防治赤霉病最经济有效的手段。目前在生产上应用的抗源很少,越来越多的研究者将目光转移到小麦的近缘属种,寻找新的抗源以及寻求新的育种突破。携带抗性基因的外源染色体可以通过染色体工程手段以附加系、代换系和易位系等形式导入小麦。综述了将大赖草等多个小麦近缘种的抗赤霉病基因导入普通小麦、创制抗病外源种质和育种利用的最新研究进展,以期为小麦抗赤霉病育种提供参考信息。     

QTL associated with Fusarium head blight resistance in the soft red winter wheat Ernie

Fusarium head blight (FHB), mainly caused by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schw. (Petch)], is an increasingly important disease of wheat (Triticum aestivum L.). Host-plant resistance provides the best hope for reducing economic losses associated with FHB, but new sources of resistance are limited. The moderately resistant winter wheat cultivar, Ernie, may provide a source of resistance that differs from Sumai 3 but these genes have not been mapped. Also hindering resistance breeding may be associations of resistance with agronomic traits such as late maturity that may be undesirable in some production environments. This research was conducted to identify QTL associated with type II FHB resistance (FHB severity, FHBS), and to determine if they are associated with days to anthesis (DTA), number of spikelets (NOS), and the presence/absence of awns. Two hundred and forty-three F₈ recombinant inbred lines from a cross between the resistant cultivar, Ernie and susceptible parent, MO 94-317 were phenotyped for type II FHB resistance using point inoculation in the greenhouse during 2002 and 2003. Genetic linkage maps were constructed using 94 simple sequence repeat (SSR) and 146 amplified fragment length polymorphic (AFLP) markers. Over years four QTL regions on chromosomes 2B, 3B, 4BL and 5A were consistently associated with FHB resistance. These QTL explained 43.3% of the phenotypic variation in FHBS. Major QTL conditioning DTA and NOS were identified on chromosome 2D. Neither the QTL associated with DTA and NOS nor the presence/absence of awns were associated with FHB resistance in Ernie. Our results suggest that the FHB resistance in Ernie appears to differ from that in Sumai 3, thus pyramiding the QTL in Ernie with those from Sumai 3 could result in enhanced levels of FHB resistance in wheat.     

A resistance-like gene identified by EST mapping and its association with a QTL controlling Fusarium head blight infection on wheat chromosome 3BS.

Fusarium head blight (FHB) is a major disease in the wheat growing regions of the world. A quantitative trait locus (QTL) on the short arm of chromosome 3B controls much of the variation for resistance. The cloning of candidate disease-resistance genes for FHB QTLs on chromosome 3B can provide further elucidation of the mechanisms that control resistance. However, rearrangements and divergence during plant genome evolution often hampers the identification of sequences with similarity to known disease-resistance genes. This study focuses on the use of wheat expressed sequence tags (ESTs) that map to the region on chromosome 3B containing the QTL for FHB resistance and low-stringency BLAST searching to identify sequences with similarity to known disease-resistance genes. One EST rich with leucine repeats and low similarity to a protein kinase domain of the barley Rpg1 gene was identified. Genetic mapping using a Ning894037 x Alondra recombinant inbred (RI) population showed that this EST mapped to the QTL on the short arm of chromosome 3B and may represent a portion of a newly diverged gene contributing to FHB resistance. The EST is a new marker suitable for marker-assisted selection and provides a starting point to begin map-based cloning for chromosome walking and investigate new diverged genes at this locus.     

Identification of QTLs for resistance to Fusarium head blight, DON accumulation and associated traits in the winter wheat variety Arina

Fusarium head blight (FHB) of wheat has become a serious threat to wheat crops in numerous countries. In addition to loss of yield and quality, this disease is of primary importance because of the contamination of grain with mycotoxins such as deoxynivalenol (DON). The Swiss winter cultivar Arina possesses significant resistance to FHB. The objective of this study was to map quantitative trait loci (QTL) for resistance to FHB, DON accumulation and associated traits in grain in a double haploid (DH) population from a cross between Arina and the FHB susceptible UK variety Riband. FHB resistance was assessed in five trials across different years and locations. Ten QTL for resistance to FHB or associated traits were detected across the trials, with QTL derived from both parents. Very few of the QTL detected in this study were coincident with those reported by authors of two other studies of FHB resistance in Arina. It is concluded that the FHB resistance of Arina, like that of the other European winter wheat varieties studied to date, is conferred by several genes of moderate effect making it difficult to exploit in marker-assisted selection breeding programmes. The most significant and stable QTL for FHB resistance was on chromosome 4D and co-localised with the Rht–D1 locus for height. This association appears to be due to linkage of deleterious genes to the Rht-D1b (Rht2) semi-dwarfing allele rather than differences in height per se. This association may compromise efforts to enhance FHB resistance in breeding programmes using germplasm containing this allele.     

Inheritance of resistance to Fusarium head blight in three European winter wheat populations

Fusarium head blight (FHB) resistance is of particular importance in wheat breeding programmes due to the detrimental effects of this fungal disease on human and animal health, yield and grain quality. Segregation for FHB resistance in three European winter wheat populations enabled the identification of resistance loci in well-adapted germplasm. Populations obtained from crosses of resistant cultivars Apache, History and Romanus with susceptible semi-dwarfs Biscay, Rubens and Pirat, respectively, were mapped and analysed to identify quantitative trait loci (QTL) for FHB severity, ear emergence time and plant height. The results of the present study together with previous studies in UK winter wheat indicated that the semi-dwarfing allele Rht-D1b seems to be the major source for FHB susceptibility in European winter wheat. The high resistance level of the cultivars Romanus and History was conditioned by several minor resistance QTL interacting with the environment and the absence of Rht-D1b. In contrast, the semi-dwarf parents contributed resistance alleles of major effects apparently compensating the negative effects of Rht-D1b on FHB reaction. The moderately resistant cultivar Apache contributed a major QTL on chromosome 6A in a genome region previously shown to carry resistance loci to FHB. A total of 18 genomic regions were repeatedly associated with FHB resistance. The results indicate that common resistance-associated genes or genomic regions are present in European winter wheats.     

Molecular mapping of QTLs for Fusarium head blight resistance in spring wheat. II. Resistance to fungal penetration and spread

Fusarium head blight (FHB, scab) causes severe yield and quality losses, but the most serious concern is the mycotoxin contamination of cereal food and feed. The cultivation of resistant varieties may contribute to integrated control of this fungal disease. Breeding for FHB resistance by conventional selection is feasible, but tedious and expensive. The aim of this work was to detect QTLs for combined type I and type II resistance against FHB and estimate their effects in comparison to the QTLs identified previously for type II resistance. A population of 364, F1 derived doubled-haploid (DH) lines from the cross 'CM-82036' (resistant)/'Remus' (susceptible) was evaluated for components of FHB resistance during 2 years under field conditions. Plants were inoculated at anthesis with a conidial suspension of Fusarium graminearum or Fusarium culmorum. The crop was kept wet for 20 h after inoculation by mist-irrigation. Disease severity was assessed by visual scoring. Initial QTL analysis was performed on 239 randomly chosen DH lines and extended to 361 lines for putative QTL regions. Different marker types were applied, with an emphasis on PCR markers. Analysis of variance, as well as simple and composite interval mapping, revealed that two genomic regions were significantly associated with FHB resistance. The two QTLs on chromosomes 3B (Qfhs.ndsu-3BS) and 5A (Qfhs.ifa-5A) explained 29 and 20% of the phenotypic variance, respectively, for visual FHB severity. Qfhs.ndsu-3BS appeared to be associated mainly with resistance to fungal spread, and Qfhs.ifa-5A primarily with resistance to fungal penetration. Both QTL regions were tagged with flanking SSR markers. These results indicate that FHB resistance was under the control of two major QTLs operating together with unknown numbers of minor genes. Marker-assisted selection for these two major QTLs appears feasible and should accelerate the development of resistant and locally adapted wheat cultivars.     

Genetic characterization of QTL associated with resistance to Fusarium head blight in a doubled-haploid spring wheat population.

Fusarium head blight (FHB) is one of the most important fungal wheat diseases worldwide. Understanding the genetics of FHB resistance is the key to facilitating the introgression of different FHB resistance genes into adapted wheat. The objectives of the present study were to detect and map quantitative trait loci (QTL) associated with FHB resistance genes and characterize the genetic components of the QTL in a doubled-haploid (DH) spring wheat population using both single-locus and two-locus analysis. A mapping population, consisting of 174 DH lines from the cross between DH181 (resistant) and AC Foremost (susceptible), was evaluated for type I resistance to initial infection during a 2-year period in spray-inoculated field trials, for Type II resistance to fungal spread within the spike in 3 greenhouse experiments using single-floret inoculation, and for resistance to kernel infection in a 2001 field trial. One-locus QTL analysis revealed 7 QTL for type I resistance on chromosome arms 2DS, 3AS, 3BS, 3BC (centromeric), 4DL, 5AS, and 6BS, 4 QTL for type II resistance on chromosomes 2DS, 3BS, 6BS, and 7BL, and 6 QTL for resistance to kernel infection on chromosomes 1DL, 2DS, 3BS, 3BC, 4DL, and 6BS. Two-locus QTL analysis detected 8 QTL with main effects and 4 additive by additive epistatic interactions for FHB resistance and identified novel FHB resistance genes for the first time on chromosomes 1DL, 4AL, and 4DL. Neither significant QTL by environment interactions nor epistatic QTL by environment interactions were found for either type I or type II resistance. The additive effects of QTL explained most of the phenotypic variance for FHB resistance. Marker-assisted selection for the favored alleles at multiple genomic regions appears to be a promising tool to accelerate the introgression and pyramiding of different FHB resistance genes into adapted wheat genetic backgrounds.     

Microsatellite analysis of wheat chromosome 2D allows the reconstruction of chromosomal inheritance in pedigrees of breeding programmes

Fusarium head blight (FHB, scab) is a fungal disease of wheat and other small cereals that is found in both temperate and semi-tropical regions. FHB causes severe yield and quality losses, but the most-serious concern is the possible mycotoxin contamination of cereal food and feed. Breeding for FHB resistance by conventional selection is feasible, but tedious and expensive. This study was conducted to identify and map DNA markers associated with FHB resistance genes in wheat. A population of 364 F₁-derived doubled-haploid (DH) lines from the cross ’CM-82036’ (resistant)/’Remus’ (susceptible) was evaluated for Type II resistance (spread within the spike) during 2 years under field conditions. Marker analysis was performed on 239 randomly chosen DH lines. Different marker types were applied, with an emphasis on AFLP and SSR markers. Analysis of variance, as well as simple and composite interval mapping, were applied. Three genomic regions were found significantly associated with FHB resistance. The most-prominent effect was detected on the short arm of chromosome 3B, explaining up to 60% of the phenotypic variance for Type II FHB resistance. A further QTL was located on chromosome 5A and a third one on 1B. The QTL regions on 3B and 5A were tagged with flanking SSR markers, the 1B QTL was found associated with the high-molecular-weight glutenin locus. These results indicate that FHB resistance is under control of a few major QTLs operating together with unknown numbers of minor genes. Marker-assisted selection for these major QTLs involved in FHB resistance appears feasible and should accelerate the development of resistant and agronomically improved wheat cultivars. Received: 25 January 2001 / Accepted: 18 February 2001     

Validation of EST-derived STS markers localized on Qfhs.ndsu-3BS for Fusarium head blight resistance in wheat using a 'Wangshuibai' derived population

A few EST-derived STS markers localized on Qfhs.ndsu-3BS, a major QTL for resistance to Fusarium head blight (FHB) in wheat, have been previously identified in the 'Sumai 3'/'Stoa' population. In this study, we used a 'Wangshuibai' (resistant)/'Seri82' (susceptible) derived population, linkage group, QTL, and quantitative gene expression analysis to assess the genetic background dependence and stability of the EST-derived STS markers for use in marker aided selection to improve FHB resistance in wheat. Based on our results, a QTL in the map interval of Xsts3B-138_1-Xgwm493 on chromosome 3BS was detected for FHB resistance, which accounted for up to 16% of the phenotypic variation. BLASTN analysis indicated that Xsts3B-138_1 sequence had significant similarity with the resistance gene analogue. Real-time quantitative PCR showed that the relative expression of Xsts3B-1381 in 'Wangshuibai' at 96 h after inoculation was 2.6 times higher than 'Seri82'. Our results underlined that EST-derived STS3B-138 markers could be predominantly used in marker aided selection to improve FHB resistance in wheat.