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1.
The inheritance of Fusarium head blight (FHB) resistance was investigated in eight western European wheat lines using a half-diallel of F1 crosses. The parents and F1 crosses were point-inoculated, with a highly aggressive isolate of Fusarium graminearum, in replicated field and glasshouse trials. Type II resistance was assessed by measuring the % FHB spread and % wilted tips. There was a good correlation between the two disease parameters, % FHB spread area under the disease progress curve (AUDPC) and % wilted tips AUDPC (r = 0.86, P < 0.01). Correlation coefficients between the field and glasshouse environments were r = 0.46 (P < 0.01) for % FHB spread AUDPC and r = 0.40 (P < 0.05) for % wilted tips AUDPC. Both general combining ability (GCA) and specific combining ability (SCA) effects influenced the inheritance of FHB resistance, suggesting that in this set of parents both additive and non-additive (dominance or epistatic) effects influence the inheritance of type II FHB resistance. Highly significant GCA-by-environment (P < 0.0001) and SCA-by-environment (P < 0.005) interactions were also observed. Specific combinations of western European wheat varieties were identified with type II FHB resistance at a level equal to or more resistant than the winter wheat variety ‘Arina’.  相似文献   

2.
Fusarium head blight (FHB), caused primarily by Fusarium graminearum (Schwabe), is an important wheat disease. In addition to head blight, F. graminearum also causes Fusarium seedling blight (FSB) and produces the mycotoxin deoxynivalenol (DON) in the grain. The objectives of this study were: (1) to compare the relationship between resistance of wheat lines to F. graminearum in the seedlings and spikes and (2) to determine whether the quantitative trait loci (QTL) for FSB were the same as QTLs for FHB resistance and DON level reported for the same population previously (Somers et al. 2003). There was no relationship between FSB infection and FHB index or DON content across the population. A single QTL on chromosome 5B that controlled FSB resistance was identified in the population; the marker WMC75 explained 13.8% of the phenotypic variation for FSB. This value implies that there may be other QTL with minor effects present, but they were not detected in the analysis. Such a QTL on chromosome 5B was not reported previously among the QTLs associated with FHB resistance and DON level in this population. However, because of recombination, some lines in the present study have Fusarium resistance for both seedling and head blight simultaneously. For example, DH line HC 450 had the highest level of resistance to FSB and FHB and was among the ten lines with lowest DON content. This line is a good candidate to be used as a parent for future crosses in breeding for Fusarium seedling resistance, together with breeding for head blight resistance. This approach may be effective in increasing overall plant resistance to Fusarium.  相似文献   

3.
Durum wheat is the most important tetraploid wheat mainly used for semolina and pasta production, but is notorious for its high susceptibility to Fusarium head blight (FHB). Our objectives were to identify and characterize quantitative trait loci (QTL) in winter durum and to evaluate the potential of genomic approaches for the improvement of FHB resistance. Here, we employed an international panel of 170 winter and 14 spring durum lines, phenotyped for Fusarium culmorum resistance at five environments. Heading date, plant height and mean FHB severity showed significant genotypic variation with high heritabilities and FHB resistance was negatively correlated with both heading date and plant height. The dwarfing gene Rht‐B1 significantly affected FHB resistance and the genome‐wide association scan identified eight additional QTL affecting FHB resistance, explaining between 1% and 14% of the genotypic variation. A genome‐wide prediction approach yielded only a slightly improved predictive ability compared to marker‐assisted selection based on the four strongest QTL. In conclusion, FHB resistance in durum wheat is a highly quantitative trait and in breeding programmes may best be tackled by classical high‐throughput recurrent phenotypic selection that can be assisted by genomic prediction if marker profiles are available.  相似文献   

4.
Fusarium head blight (FHB) infects all cereals including maize and is considered a major wheat disease, causing yield losses and mycotoxin contamination. This study aimed to compare the realized selection gain from marker and phenotypic selection in European winter wheat. A double cross (DC) combined three FHB resistance donor-QTL alleles (Qfhs.lfl-6AL and Qfhs.lfl-7BS from ‘Dream’, and one QTL on chromosome 2BL from ‘G16-92’) with two high yielding, susceptible winter wheats, ‘Brando’ and ‘LP235.1’. The base population of 600 DC derived F1 lines was on one hand selected for the respective QTLs by SSR markers (marker-selected cycle, CM), resulting in 35 progeny possessing different combinations of beneficial donor-QTL alleles. On the other hand it was selected phenotypically, only by FHB rating, and the best 20 lines were recombined and selfed (phenotypically selected cycle, CP). The variants CP, CM, and an unselected variant (C0) were tested at four locations by inoculation of Fusarium culmorum. Resistance was measured as the mean of multiple FHB ratings (0–100%). FHB severity was reduced through both phenotypic and marker selection by 6.2 vs. 5.0%, respectively. On a per-year basis, marker selection by 2.5% was slightly superior to phenotypic selection with 2.1%, because the first variant saved 1 year. Marker-selected lines were on average 8.6 cm taller than phenotypically selected lines. A high genetic variation within the marker-selected variant for FHB resistance and the high effect of a resistance-QTL allele on straw length indicate that additional phenotypic selection will further enhance selection gain.  相似文献   

5.
Fusarium head blight (FHB) is a destructive disease of barley. The genetics and expression of resistance to FHB in barley is complex, and various spike characters are thought to possibly influence resistance. Tests using spray-inoculation of Fusarium graminearum at anthesis in greenhouse environments showed that two-rowed and cleistogamous varieties from Japan belong to the highest resistance group, while six-rowed and chasmogamous varieties are mostly susceptible. In order to evaluate the effect of such spike characters, including row type and flowering type, on FHB resistance, near-isogenic lines (NILs) differing in these characters were tested for their resistance. Two testing methods were used: the pot-plant and cut-spike methods, in which spikes at anthesis were spray-inoculated in greenhouse environments. The chasmogamous NILs and some six-rowed NILs were significantly more diseased than cleistogamous and two-rowed parent lines, respectively, and the difference in FHB severity was greater and more stable between cleistogamous/chasmogamous NIL pairs than between two-/six-rowed pairs. Slight or no differences were observed in glaucous/non-glaucous, normal/dense spike, normal/uzu type and normal/deficiens NIL pairs. The results indicate that the contribution of cleistogamy and/or the genetic background toward FHB resistance is more than that of row type and the other tested spike characters. Further, it should be possible to develop six-rowed varieties with FHB resistance nearly as good as that of the two-rowed varieties.  相似文献   

6.
Rye is a multi-purpose cereal crop grown in Central and Eastern Europe as well as in Western Canada. Fusarium head blight (FHB) is one of the diseases that have a severe negative impact on rye, but knowledge about FHB resistance at the genomic level is totally missing in rye. The objective of this study was to elucidate the genetic architecture of FHB resistance in winter rye using genome-wide association (GWA) mapping complemented by genomic prediction (GP) in comparison with marker-assisted selection (MAS). Additionally, plant height and heading stage were analysed. A panel of 465 S1-inbred lines of winter rye was phenotyped in three environments (location–year combinations) for FHB resistance by inoculation with Fusarium culmorum and genotyped with a 15k SNP array. Significant genotypic variation and high heritabilities were found for FHB resistance, heading stage and plant height. FHB did not correlate with heading stage, but was moderately correlated with plant height (r = −.52, p < .001) caused by some susceptible short inbred lines. The GWA scan identified 15 QTL for FHB resistance that jointly explained 74% of the genotypic variance. In addition, we detected 11 QTL for heading stage and 8 QTL for plant height, explaining 26% and 14% of the genotypic variance, respectively. A genome-wide prediction approach resulted in 44% higher prediction abilities than marker-assisted selection for FHB resistance. In conclusion, genomic approaches appear promising to improve and accelerate breeding for complex traits in winter rye.  相似文献   

7.
Fusarium head blight (FHB), caused by Fusarium graminearum and Fusarium culmorum, is a devastating disease in cereals. This study was undertaken to estimate progeny means and variances in each of five winter triticale and winter wheat crosses using unselected F2−derived lines in F4 or F5 generation bulked at harvest of the previous generation. Fifty (triticale) and 95 (wheat) progeny per cross were inoculated in two (triticale) or three (wheat) field environments. FHB rating was assessed on a whole-plot basis. Mean disease severities of the parents ranged from 2.3 to 6.4 in triticale and from 3.1 to 6.5 in wheat on a 1-to-9 scale (1 = symptomless, 9 = 100% infected). The midparent values generally resembled the means of their derived progeny. Significant (P < 0.01) genotypic variance was detected within each cross, but genotype × environment interaction and error variances were also high for both crops. Medium to high entry-mean heritabilities (0.6–0.8) underline the feasibility of selecting F2-derived bulks on a plot basis in several environments. Phenotypic correlation of FHB resistance between generation F2:4 and F2:5 was r = 0.87 (P < 0.01) tested across 150 wheat bulks at two locations. Our estimates of selection gain are encouraging for breeders to improve FHB resistance in triticale and wheat by recurrent selection within adapted materials.  相似文献   

8.
Fusarium head blight (FHB) caused by Fusarium spp. is one of the most important fungal diseases of wheat (Triticum aestivum L.) in regions with wet climatic conditions. Improvement of the FHB resistance by developing new varieties requires sound knowledge on the inheritance of resistance. An 8 × 8 diallel analysis was performed to estimate general (GCA) and specific (SCA) combining ability of resistance to FHB. The F1s and parental lines were evaluated under artificial inoculation at the experimental field of IFA-Tulln, Austria during 2001 and 2002. Disease severity was evaluated by repeated scoring of the percentage of infected spikelets and calculating an area under the disease progress curve (AUDPC). The analysis of combining ability across two years showed highly significant GCA and non-significant SCA effects indicating the importance of additive genetic components in controlling FHB resistance. The significant GCA-by-year interaction presented the role of environmental factors in influencing the FHB reaction of wheat lines. The comparison of the crosses with low FHB infection and GCA effects of their parents showed that such crosses involved at least one parent with high or average negative GCA effect. The results revealed that it is feasible to use highly or moderately resistant genotypes and conventional breeding methods to achieve genetic improvement of FHB resistance in spring wheat.  相似文献   

9.
Sources of resistance to Fusarium spp. are needed to develop maize hybrids resistant to the accumulation of fungal mycotoxins in the grain. In a search for resistant germplasm in 1999 and 2000, a set of Argentinian maize populations was evaluated in Ottawa, Canada, for resistance to ear rots after inoculation with local isolates of Fusarium verticillioides and F. graminearum. Sixteen of these populations, varying in observed resistance levels, were re-evaluated in 2003 and 2004 in Pergamino, Argentina, using local isolates of the same fungi. Conidial suspensions of each fungal species were inoculated into the silk channel of primary ears. Disease severity was assessed after physiological maturity using a scale based on the percentage of visibly infected kernels. Genotype effect was more important than genotype-by-fungal species or genotype-by-fungal species-by-environment interaction effects. In addition, disease severity levels associated with each fungal species were positively correlated (P < 0.05) (r = 0.90, r = 0.81, r = 0.87 and r = 0.53, in Ottawa 1999 and 2000, and Pergamino 2003 and 2004, respectively). Populations ARZM 01107, ARZM 07138, ARZM 10041, ARZM 13031, ARZM 16002 and Pora INTA exhibited the highest and most stable resistance to both species. Considering that disease resistance exhibited low specificity to the environment and to the fungal species in evaluations conducted in a wide range of environments and with fungal isolates collected from different hemispheres, the most resistant populations are potential sources of genes for stable resistance to these Fusarium spp.  相似文献   

10.
K. Matsui    M. Yoshida    T. Ban    T. Komatsuda  N. Kawada 《Plant Breeding》2002,121(3):237-240
Two types of male‐sterile cytoplasm, designated msm1 and msm2, in barley were investigated to determine whether these cytoplasms confer resistance to barley yellow mosaic virus (Ba YMV) and Fusarium head blight (FHB). Alloplasmic lines and isogenic lines of two cultivars showed the same reaction to each Ba YMV as that of their euplasmic lines. This demonstrates that the barley male‐sterile cytoplasms msm1 and msm2 have no effect on resistance to BaYMV. No significant difference in reactions to FHB was recognized among fertile alloplasmic lines of ‘Adorra’, but the difference in reactions to FHB between fertile and sterile isogenic lines of ‘Adorra’ was significant. The damage caused by FHB in the male‐sterile lines that produced sterile pollen was significantly greater than the damage in a sterile line that did not produce pollen. These results suggest that pollen or anthers are important factors in infection with or spread of FHB. For production of hybrid seeds, male‐sterile lines with no pollen production, such as those with msm1 male‐sterile cytoplasm, would reduce FHB infestation.  相似文献   

11.
Fusarium head blight (FHB) in triticale (× Triticosecale Wittmack) results in yield losses and mycotoxin contamination, for example, by deoxynivalenol (DON). This study aimed to analyse the correlation between FHB severity and DON content in a DH population of 146 entries across environments. Additionally, Fusarium damaged kernel (FDK) rating, heading stage and plant height were recorded. Highly significant (P < 0.001) genotypic variances were found throughout, but also significant (P < 0.001) genotype–environment interaction variances occurred. Correlation between FHB severity and heading stage or plant height was low (r = 0.144 and r = ?0.153, P < 0.10). A prediction of DON content from FHB severity or FDK rating is not possible caused by low correlations (r = 0.315 and 0.572, respectively, P < 0.001). A common quantitative trait locus (QTL) for all FHB‐related traits was found on wheat chromosome 2A being of minor importance for FHB severity, but of high importance for DON content and FDK rating. Another QTL on rye chromosome 5R was more important for FHB severity. In conclusion, DON content has to be measured in triticale after selection for FHB severity to gain for healthy and mycotoxin‐reduced feed.  相似文献   

12.
Summary Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases.  相似文献   

13.
We report on the identification of FHB ( Fusarium head blight) resistance quantitative trait loci (QTL) of the donor 'G93010' (Bussard/Ning8026) in the background of elite breeding material adapted to the central European climate. With a multiple interval mapping method, two major resistance QTL were identified. Qfhs.lfl-7BS/5BL and Qfhs.lfl-6BS reduced FHB severity individually by 30% and 24%. The combination of both QTL decreased disease severity most effectively by about one half. Qfhs.lfl-6BS is most likely identical to Fhb2 , thus, the effectiveness of Fhb2 in central European breeding material has been validated. Qfhs.lfl-7BS/5BL overlapped with QTL for plant height and heading date. Nevertheless, the selection of lines combining a good FHB resistance level with an acceptable plant height was possible. As the donors of the QTL have probably not yet been utilized in European breeding material, we identified well-adapted lines of the mapping population as valuable donors for marker-assisted breeding programmes.  相似文献   

14.
Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive fungal diseases. Wide spread of FHB causes yield loss, quality reduction, and accumulation of poisonous mycotoxins. Twenty-three Korean wheat cultivars and a known FHB resistant cultivar ‘Sumai 3’ were tested for Type I and Type II resistance to FHB and evaluated for grain characteristics. Wheat cultivars showed infection scores of 0.6 (the lowest) to 7.8 (the highest) in response to the Fusarium inoculation for Type I evaluation. Three Korean cultivars, ‘Chungkye’ (1.8), ‘Tapdong’ (1.8), and ‘Jinpoom’ (1.6) showed relatively good FHB resistance compared to ‘Sumai 3’ (0.6) for Type I evaluation. On the other hand, Type II evaluation scores ranged between 1.4 and 3.6. The infection scores of ‘Uri’ (1.4) and ‘Jinpoom’ (1.4) were particularly low and even lower than “Sumai 3” (1.6). The relationship between grain properties and FHB severity was evaluated. Grain length was positively correlated with Type II evaluation. Spike length and total polyphenol content were negatively correlated with FHB severity of Type I evaluation. Grain properties were negatively or positively correlated with FHB severity. The obtained results indicated that some of the grain parameters could be employed in the development of wheat lines with improved FHB resistance.  相似文献   

15.
Fusarium head blight (FHB), caused by the fungal plant pathogen Fusarium, is a fungal disease that occurs in wheat and can cause significant yield and grain quality losses. The present paper examines variation in the resistance of spring wheat lines derived from a cross between Zebra and Saar cultivars. Experiments covering 198 lines and parental cultivars were conducted in three years, in which inoculation with Fusarium culmorum was applied. Resistance levels were estimated by scoring disease symptoms on kernels. In spite of a similar reaction of parents to F. culmorum infection, significant differentiation between lines was found in all the analyzed traits. Seven molecular markers selected as linked to FHB resistance QTLs gave polymorphic products for Zebra and Saar: Xgwm566, Xgwm46, Xgwm389, Xgwm533, Xgwm156, Xwmc238, and Xgwm341. Markers Xgwm389 and Xgwm533 were associated with the rate of Fusarium-damaged kernels (FDK) as well as with kernel weight per spike and thousand kernel weight in control plants. Zebra allele of marker Xwmc238 increased kernel weight per spike and thousand kernel weight both in control and infected plants, whereas Zebra allele of marker Xgwm566 reduced the percentage of FDK and simultaneously reduced the thousand kernel weight in control and infected plants.  相似文献   

16.
Semi‐dwarf wheat is an important prerequisite for releasing a successful commercial cultivar in high‐yielding environments. In Northern Europe, this aim is achieved by using one of the dwarfing genes Rht‐B1 (formerly known as Rht‐1) or Rht‐D1 (Rht‐2). Both genes, however, result in a higher susceptibility to Fusarium head blight (FHB). We analysed the possibility to use the two non‐adapted FHB resistance quantitative trait loci Fhb1 and Fhb5 (syn. QFhs.ifa‐5A) to counterbalance the negative effect of the dwarfing allele Rht‐D1b in a winter wheat population of 585 doubled‐haploid (DH) lines segregating for the three loci. All lines were inoculated with Fusarium culmorum at four locations and analysed for FHB severity, plant height, and heading date. The DH population showed a significant (< 0.001) genotypic variation for FHB severity ranging from 3.6% to 65.9% with a very high entry‐mean heritability of 0.95. The dwarfing allele Rht‐D1b reduced plant height by 24 cm, but nearly doubled the FHB susceptibility (24.74% vs. 12.74%). The resistance alleles of Fhb1 and Fhb5 reduced FHB susceptibility by 6.5 and 11.3 percentage points, respectively. Taken all three loci together, Fhb5 alone was already able to reduce FHB susceptibility to the same extent as Rht‐D1b increased it. This opens new avenues for selecting semi‐dwarf wheat by marker‐assisted introgression of Fhb5 without the enhancement of FHB susceptibility.  相似文献   

17.
R. A. Browne  B. M. Cooke 《Euphytica》2005,141(1-2):23-32
Resistance of wheat cultivars from the UK, 2003 recommended list were evaluated against Fusarium culmorum, F. graminearum, Microdochium nivale var. majus and var. nivale, F. avenaceum and F. poae using a seed germination assay and related to previously published data on detached leaf assays, using M. nivale, and UK recommended list Fusarium head blight (FHB) resistance ratings. Significant cultivar differences were found after inoculation with all fungal species with the exception of F. poae where the decline in the percentage of seed germinating relative to the controls was small. Correlations of the percentage seed germinating inoculated with the remaining Fusarium spp. and M. nivale were high (r = 0.68; P < 0.01 to r = 0.94; P < 0.001). Overall, F. graminearum caused the greatest reduction with a mean seed germination of 61.7% relative to the controls followed by F. avenaceum (65.5%), M. nivale var. majus (67.2%), F. culmorum (76.6%), M. nivale var. nivale (89.2%) and was least for F. poae (92.5%). The resistance detected in the germination assay was significantly correlated to whole plant FHB resistance ratings (rs = 0.45; P < 0.05) but was not correlated to partial disease resistance (PDR) components detected using the detached leaf assay, namely, incubation period, latent period and lesion length. The results suggest that while resistances detected in the seed germination and detached leaf assays may in part share a common genetic basis to FHB resistance, resistances detected in both in vitro assays are independent of each other. Resistances detected in the seed germination assay had a lower correlation with FHB resistance ratings against F. culmorum, than those detected by latent period in the detached leaf assay.  相似文献   

18.
Fusarium head blight (FHB) caused by Fusarium species, is among the most devastating wheat diseases, causing losses in numerous sectors of the grain industry through yield and quality reduction, and the accumulation of poisonous mycotoxins. A germplasm collection of spring and winter wheat, including nine reference cultivars, was tested for Type II FHB resistance and deoxynivalenol (DON) content. Genetic diversity was evaluated on the basis of Simple Sequence Repeat (SSR) markers linked to FHB resistance quantitative trait loci (QTLs) and Diversity Arrays Technology (DArT) markers. The allele size of the SSR markers linked to FHB resistance QTLs from known resistance sources was compared to a germplasm collection to determine the presence of these QTLs and to identify potentially novel sources of resistance. Forty-two accessions were identified as resistant or moderately resistant to Fusarium spread, and two also had very low DON concentrations. Genetic relationships among wheat accessions were generally consistent with their geographic distribution and pedigree. SSR analysis revealed that several resistant accessions carried up to four of the tested QTLs. Resistant and moderately resistant lines without any known QTLs are considered to be novel sources of resistance that could be used for further genetic studies.  相似文献   

19.
Fusarium head blight (FHB, scab) caused by Fusarium spp. is a widespread disease of cereals causing relevant yield and quality losses and contaminating cereal products with mycotoxins. Breeding resistant cultivars is the method of choice for controlling the disease. Resistance to FHB is a quantitative trait and is most likely governed by several genes. We present the results of an F1 diallel analysis of FHB resistance involving six resistant and one susceptible European winter wheat genotypes of diverse origin in order to identify promising combinations for the selection of improved cultivars. Parents and F1s including reciprocals were evaluated for FHB resistance in an artificially inoculated field trial. Two traits were assessed: visual disease symptoms on the heads and the percentage of Fusarium damaged kernels in a harvested sample. General combining ability (GCA) and specific combining ability (SCA) effects were statistically significant for visual symptoms and kernel damage, whereas reciprocal effects were small or not significant. Heterosis for resistance was common, indicating that the parental genotypes possess different resistance genes. Selection of transgressive segregates should be feasible from such heterotic combinations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Fusarium head blight (FHB) is a cereal disease of major importance responsible for yield losses and mycotoxin contaminations in grains. Here, we introduce a new measurement approach to quantify FHB severity on grains based on the evaluation of the whitened kernel surface (WKS) using digital image analysis. The applicability of WKS was assessed on two bread wheat and one triticale grain sample sets (265 samples). Pearson correlation coefficients between Fusarium‐damaged kernels (FDK) and WKS range from r = 0.77 to r = 0.81 and from r = 0.61 to r = 0.86 for the correlation between deoxynivalenol (DON) content and WKS. This new scoring method facilitates fast and reliable assessment of the resistance to kernel infection and shows significant correlation with mycotoxin content. WKS can be automated and does not suffer from the “human factor” inherent to visual scorings. As a low‐cost and fast approach, this method appears particularly attractive for breeding and genetic analysis of FHB resistance where typically large numbers of experimental lines need to be evaluated, and for which WKS is suggested as an alternative to visual FDK scorings.  相似文献   

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