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1.
Micic Z Hahn V Bauer E Schön CC Knapp SJ Tang S Melchinger AE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(7):1474-1484
In many sunflower-growing regions of the world, Sclerotinia sclerotiorum (Lib.) de Bary is the major disease of sunflower (Helianthus annuus L.). In this study, we mapped and characterized quantitative trait loci (QTL) involved in resistance to S. sclerotiorum midstalk rot and two morphological traits. A total of 351 F3 families developed from a cross between a resistant inbred line from the germplasm pool NDBLOS and the susceptible line CM625 were assayed for their parental F2 genotype at 117 codominant simple sequence repeat markers. Disease resistance of the F3 families was screened under artificial infection in field experiments across two sowing times in 1999. For the three resistance traits (leaf lesion, stem lesion, and speed of fungal growth) and the two morphological traits, genotypic variances were highly significant. Heritabilities were moderate to high (h2=0.55–0.89). Genotypic correlations between resistance traits were highly significant (P<0.01) but moderate. QTL were detected for all three resistance traits, but estimated effects at most QTL were small. Simultaneously, they explained between 24.4% and 33.7% of the genotypic variance for resistance against S. sclerotiorum. Five of the 15 genomic regions carrying a QTL for either of the three resistance traits also carried a QTL for one of the two morphological traits. The prospects of marker-assisted selection (MAS) for resistance to S. sclerotiorum are limited due to the complex genetic architecture of the trait. MAS can be superior to classical phenotypic selection only with low marker costs and fast selection cycles. 相似文献
2.
C. Egea-Gilabert G. Bilotti M. E. Requena M. Ezziyyani J. M. Vivo-Molina M. E. Candela 《Biologia Plantarum》2008,52(1):105-109
Inheritance of 10 morphological and quantitative traits related to plant and fruit development and resistance to the pathogen
Phytophthora capsici was studied in an intraspecific cross between a non-pungent, susceptible Capsicum annuum parent (cv. Americano) and a wild, pungent and resistant line (Serrano Criollo de Morelos-334). Data were obtained from the
segregation of 166 F2 plants and 50 F3 plants in four years. Three of the traits analyzed (necrosis length, leaf width and leaf length) exhibited a transgressive
segregation. A multiple linear regression analysis was applied in order to establish a relationship between necrosis length
and some of the morphological traits measured such as length and width of leaf, length, diameter and mass of fruit, capsaicin
content in fruits, and presence of hair on leaves and stems. The results identified a linear dependence between necrosis length
(as an inverse measurement of resistance) and leaf width, fruit diameter and hair presence in the stem. Pungency was not related
with resistance. 相似文献
3.
Micic Z Hahn V Bauer E Schön CC Melchinger AE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,110(8):1490-1498
Midstalk rot caused by Sclerotinia sclerotiorum is an important disease of sunflower in its main areas of cultivation. The objectives of this study were to (1) verify quantitative trait loci (QTL) for midstalk-rot resistance found in F3 families of the NDBLOSsel × CM625 population in recombinant inbred lines (RIL) derived from the same cross; (2) re-estimate their position and genetic effects; (3) draw inferences about the predictive quality of QTL for midstalk-rot resistance identified in the F3 families as compared to those in the RIL. Phenotypic data for three resistance (leaf lesion, stem lesion, and speed of fungal growth) and two morphological traits (leaf length and leaf length with petiole) were obtained from 317 RIL following artificial infection in field experiments across two environments. For genotyping the 248 RIL, we selected 41 simple sequence repeat (SSR) markers based on their association with QTL for Sclerotinia midstalk-rot resistance in an earlier study. The resistance traits showed intermediate to high heritabilities
and were significantly correlated with each other
Genotypic correlations between F3 families and the RIL were highly significant and ranged between 0.50 for leaf length and 0.64 for stem lesion. For stem lesion, two genomic regions on linkage group (LG) 8 and LG16 explaining 26.5% of the genotypic variance for Sclerotinia midstalk-rot resistance were consistent across generations. For this trait, the genotypic correlation between the observed performance and its prediction based on QTL positions and effects in F3 families was surprisingly high
The genetic effects and predictive quality of these two QTL are promising for application in marker-assisted selection to Sclerotinia midstalk-rot resistance. 相似文献
4.
A. L. Dingerdissen H. H. Geiger M. Lee A. Schechert H. G. Welz 《Molecular breeding : new strategies in plant improvement》1996,2(2):143-156
Quantitative trait loci (QTL) involved in the resistance of maize to Setosphaeria turcica, the causal agent of northern leaf blight, were located by interval mapping analysis of 121 F2:3 lines derived from a cross between Mo17 (moderately resistant) and B52 (susceptible). A linkage map spanning 112 RFLP loci with 15 cM mean interval length was constructed, based on marker data recorded in a previous study. Field tests with artificial inoculation were conducted at three sites in tropical mid- to high-altitude regions of Kenya, East Africa. Host-plant response was measured in terms of incubation period, disease severity (five scoring dates), and the area under the disease progress curve (AUDPC). Heritability of all traits was high (around 0.75). QTL associated with the incubation period were located on chromosomes 2S and 8L. For disease severity and AUDPC, significant QTL were detected in the putative centromeric region of chromosome 1 and on 2S, 3L, 5S, 6L, 7L, 8L and 9S. On 2S the same marker interval which carried a gene enhancing latent period was also associated with reduced disease severity of juvenile plants. QTL on chromosomes 3L, 5S, 7L and 8L were significant across environments but all other QTL were affected by a large genotype x environment interaction. Partially dominant gene action for resistance as well as for susceptibility was prevailing. Single QTL explained 10 to 38% of the phenotypic variation of the traits. All but the QTL on chromosomes 1, 6 and 9 were contributed by the resistant parent Mo17. On chromosome 8L a QTL mapped to the same region as the major race-specific gene Ht2, supporting the hypothesis that some qualitative and quantitative resistance genes may be allelic.Abbreviations AUDPC
area under the disease progress curve
- CIMMYT
International Maize and Wheat Improvement Center
- KARI
Kenya Agricultural Research Institute
- NCLB
northern corn leaf blight
- QTL
quantitative trait locus/loci 相似文献
5.
Voorrips RE Finkers R Sanjaya L Groenwold R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(6):1275-1282
Anthracnose fruit rot is an economically important disease that affects pepper production in Indonesia. Strong resistance to two causal pathogens, Colletotrichum gloeosporioides and C. capsici, was found in an accession of Capsicum chinense. The inheritance of this resistance was studied in an F2 population derived from a cross of this accession with an Indonesian hot pepper variety (Capsicum annuum) using a quantitative trait locus (QTL) mapping approach. In laboratory tests where ripe fruits were artificially inoculated with either C. gloeosporioides or C. capsici, three resistance-related traits were scored: the infection frequency, the true lesion diameter (averaged over all lesions that actually developed), and the overall lesion diameter (averaged over all inoculation points, including those that did not develop lesions). One main QTL was identified with highly significant and large effects on all three traits after inoculation with C. gloeosporioides and on true lesion diameter after inoculation with C. capsici. Three other QTL with smaller effects were found for overall lesion diameter and true lesion diameter after inoculation with C. gloeosporioides, two of which also had an effect on infection frequency. Interestingly, the resistant parent carried a susceptible allele for a QTL for all three traits that was closely linked to the main QTL. The results with C. capsici were based on less observations and therefore less informative. Although the main QTL was shown to have an effect on true lesion diameter after inoculation with C. capsici, no significant QTL were identified for overall lesion diameter or infection frequency. 相似文献
6.
7.
QTLs for resistance to powdery mildew in pepper under natural and artificial infections 总被引:6,自引:0,他引:6
Lefebvre V Daubèze AM Rouppe van der Voort J Peleman J Bardin M Palloix A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(4):661-666
Epidemics of powdery mildew due to Leveillula taurica is an increasing problem in pepper production areas, particularly in coastal regions or greenhouse cultivation. The highly resistant genitor 'H3' was submitted to genetic analysis and QTL mapping in order to promote the introgression of its oligogenic resistance into large and sweet-fruited cultivars. The doubled-haploid progeny from the cross 'H3' (resistant) by 'Vania' (susceptible) was tested for resistance under both natural field infection and artificial inoculation tests, and QTL detection was compared for those two methods. Seven genomic regions including additive QTLs and epistatic interactions were detected, explaining altogether the major part of genotypic variance. Two genomic regions were common to both the evaluation methods, whereas other QTLs were method-specific, reflecting the environment dependence of powdery mildew epidemics. Orthologies with tomato genomic regions carrying resistance genes to L. taurica and Oidium lycopersicum were revealed by comparative mapping with pepper. Tight linkages between the detected QTLs and virus resistance or fruit color traits in pepper were also shown, which adds to the agronomic importance of these regions in pepper breeding programs.Communicated by G. Wenzel 相似文献
8.
Identification of quantitative trait loci controlling resistance to gray leaf spot disease in maize 总被引:4,自引:0,他引:4
M. A. Saghai Maroof Y. G. Yue Z. X. Xiang E. L. Stromberg G. K. Rufener 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(4):539-546
Breeding maize for gray leaf spot (GLS) resistance has been hindered by the quantitative nature of the inheritance of GLS resistance and by the limitations of selection under less than optimumal disease pressure. In order to identify the quantitative trait loci (QTLs) controlling GLS resistance, a cross was made between B73 (susceptible) and Va14 (resistant) to generate a large F2 population. Six GLS disease assessments were made throughout the disease season for over 1000 F2 plants in 1989, and for 600 F2-derived F3 lines replicated in two blocks in 1990. RFLP analysis for78 marker loci representing all ten maize chromosomes was conducted in 239 F2 individuals including those with the extreme GLS disease phenotypes. The GLS disease scores of the three field evaluations, each averaged over six ratings, were separately used for the interval mapping in order to determine the consistency of the QTL effects. The heavy GLS disease pressure, meticulous disease ratings, and large population size of this study afforded us the sensitivity for detecting QTL effects. QTLs located on three chromosomes (1, 4, and 8) had large effects on GLS resistance, each explaining 35.0–56.0%, 8.8–14.3%, and 7.7–11.0% of the variance, respectively. These three QTL effects were remarkably consistent across three disease evaluations over 2 years and two generations. Smaller QTL effects were also found on chromosomes 2 and 5, but the chromosome-5 effect might be a false positive because it was not repeatable even in the same location. The chromosome-1 QTLs had the largest effect or highest R2 reported for any quantitative trait to-date. Except for the chromosome-4 gene, which was from the susceptible parent B73, the resistance alleles at all QTL were derived from Va14. The resistance QTLs on chromosomes 1 and 2 appear to have additive effects, but those on chromosomes 4 and 8 are dominant and recessive, respectively. Significant interaction between the QTLs on chromosomes 1 and 4 was detected in all three evaluations. Cumulatively, the four QTLs identified in this study explained 44, 60, and 68% of the variance in F2, and in F3 replications 1 and 2, respectively. 相似文献
9.
The analysis of reciprocal genetic crosses between resistant Helicoverpa armigera strain (BH-R) (227.9-fold) with susceptible Vadodara (VA-S) strain showed dominance (h) of 0.65-0.89 and degree of dominance (D) of 0.299-0.782 suggesting Cry1Ac resistance as a semi-dominant trait. The D and h values of F1 hybrids of female resistant parent were higher than female susceptible parent, showing maternally enhanced dominance of Cry1Ac resistance. The progeny of F2 crosses, backcrosses of F1 hybrid with resistant BH-R parent did not differ significantly in respect of mortality response with resistant parent except for backcross with female BH-R and male of F1 (BH-R × VA-S) cross, suggesting dominant inheritance of Cry1Ac resistance. Evaluation of some biological attributes showed that larval and pupal periods of progenies of reciprocal F1 crosses, backcrosses and F2 crosses were either at par with resistant parent or lower than susceptible parent on treated diet (0.01 μg/g). The susceptible strain performed better in terms of pupation and adult formation than the resistant strain on untreated diet. In many backcrosses and F2 crosses, Cry1Ac resistance favored emergence of more females than males on untreated diet. The normal larval period and the body weight (normal larval growth) were the dominant traits associated with susceptible strain as contrast to longer larval period and the lower body weight (slow growth) associated with resistance trait. Further, inheritance of larval period in F2 and backcross progeny suggested existence of a major resistant gene or a set of tightly linked loci associated with Cry1Ac sensitivity. 相似文献
10.
Yang DE Jin DM Wang B Zhang DS Nguyen HT Zhang CL Chen SJ 《Molecular genetics and genomics : MGG》2005,274(3):229-234
The maize inbred lines 1145 (resistant) and Y331 (susceptible), and the F1, F2 and BC1F1 populations derived from them were inoculated with the pathogen Pythium inflatum Matthews, which causes stalk rot in Zea mays. Field data revealed that the ratio of resistant to susceptible plants was 3:1 in the F2 population, and 1:1 in the BC1F1population, indicating that the resistance to P. inflatum Matthews was controlled by a single dominant gene in the 1145×Y331 cross. The gene that confers resistance to P. inflatum Matthews was designated Rpi1 for resistance to P. inflatum) according to the standard nomenclature for plant disease resistance genes. Fifty SSR markers from 10 chromosomes were first
screened in the F2 population to find markers linked to the Rpi1 gene. The results indicated that umc1702 and mmc0371 were both linked to Rpi1, placing the resistance gene on chromosome 4. RAPD (randomly amplified polymorphic DNA) markers were then tested in the F2population using bulked segregant analysis (BSA). Four RAPD products were found to show linkage to the Rpi1 gene. Then 27 SSR markers and 8 RFLP markers in the region encompassing Rpi1 were used for fine-scale mapping of the resistance gene. Two SSR markers and four RFLP markers were linked to the Rpi1 gene. Finally, the Rpi1 gene was mapped between the SSR markers bnlg1937 and agrr286 on chromosome 4, 1.6 cM away from the former and 4.1 cM distant
from the latter. This is the first time that a dominant gene for resistance to maize stalk rot caused by P. inflatum Matthews has been mapped with molecular marker techniques. 相似文献
11.
AB-QTL analysis in spring barley. I. Detection of resistance genes against powdery mildew, leaf rust and scald introgressed from wild barley 总被引:8,自引:8,他引:0
von Korff M Wang H Léon J Pillen K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(3):583-590
The objective of this study was to map new resistance genes against powdery mildew (Blumeria graminis f. sp. hordei L.), leaf rust (Puccinia hordei L.) and scald [Rhynchosporium secalis (Oud.) J. Davis] in the advanced backcross doubled haploid (BC2DH) population S42 derived from a cross between the spring barley cultivar Scarlett and the wild barley accession ISR42-8 (Hordeum vulgare ssp. spontaneum). Using field data of disease severity recorded in eight environments under natural infestation and genotype data of 98 SSR loci, we detected nine QTL for powdery mildew, six QTL for leaf rust resistance and three QTL for scald resistance. The presence of the exotic QTL alleles reduced disease symptoms by a maximum of 51.5, 37.6 and 16.5% for powdery mildew, leaf rust and scald, respectively. Some of the detected QTL may correspond to previously identified qualitative (i.e. Mla) and to quantitative resistance genes. Others may be newly identified resistance genes. For the majority of resistance QTL (61.0%) the wild barley contributed the favourable allele demonstrating the usefulness of wild barley in the quest for resistant cultivars. 相似文献
12.
K. Song M. K. Slocum T. C. Osborn 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(1):1-10
Construction of a detailed RFLP linkage map of B. rapa (syn. campestris) made it possible, for the first time, to study individual genes controlling quantitative traits in this species. Ninety-five F2 individuals from a cross of Chinese cabbage cv Michihili by Spring broccoli were analyzed for segregation at 220 RFLP loci and for variation in leaf, stem, and flowering characteristics. The number, location, and magnitude of genes underlying 28 traits were determined by using an interval mapping method. Zero to five putative quantitative trait loci (QTL) were detected for each of the traits examined. There were unequal gene effects on the expression of many traits, and the inheritance patterns of traits ranged from those controlled by a single major gene plus minor genes to those controlled by polygenes with small and similar effects. The effect of marker locus density on detection of QTL was analyzed, and the results showed that the number of QTL detected did not change when the number of marker loci used for QTL mapping was decreased from 220 to 126; however, a further reduction from 126 to 56 caused more than 15% loss of the total QTL detected. The detection of putative minor QTL by removing the masking effects of major QTL was explored. 相似文献
13.
Suwabe K Tsukazaki H Iketani H Hatakeyama K Fujimura M Nunome T Fukuoka H Matsumoto S Hirai M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(6):997-1002
In an analysis of 114 F2 individuals from a cross between clubroot-resistant and susceptible lines of Brassica rapa L., 'G004' and 'Hakusai Chukanbohon Nou 7' (A9709), respectively, we identified two loci, Crr1 and Crr2, for clubroot (caused by Plasmodiophora brassicae Woronin) resistance. Each locus segregated independently among the F2 population, indicating that the loci reside on a different region of chromosomes or on different chromosomes. Genetic analysis showed that each locus had little effect on clubroot resistance by itself, indicating that these two loci are complementary for clubroot resistance. The resistance to clubroot was much stronger when both loci were homozygous for resistant alleles than when they were heterozygous. These results indicate that clubroot resistance in B. rapa is under oligogenic control and at least two loci are necessary for resistance.Communicated by H.C. Becker 相似文献
14.
Zhao J Udall JA Quijada PA Grau CR Meng J Osborn TC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(3):509-516
Sclerotinia stem rot, caused by fungus Sclerotinia sclerotiorum, is one of the most devastating diseases in rapeseed (Brassica napus L.). We report the identification of Quantitative trait loci (QTL) involved in the resistance to S. sclerotiorum in two segregating populations of DH lines: the HUA population, derived from a cross between a partially resistant Chinese
winter line (Hua dbl2) and a susceptible European spring line (P1804); and the MS population, derived from a partially resistant
French winter cultivar (Major) and a susceptible Canadian spring cultivar (Stellar). A petiole inoculation technique and two
scoring methods, days to wilt (DW) and stem lesion length (SLL), were used for the resistance assessment. A total of eight
genomic regions affecting resistance were detected in the HUA population, with four of these regions affecting both measures
of resistance. Only one region, which affected both measurements, was detected in the MS population. Individual QTL explained
6–22% of the variance. At five of the QTL from both populations, alleles from the resistant parent contributed to the resistance.
QTL on N2 from the HUA population had the highest LOD score and R
2 value and was detected for SLL in the first evaluation. The N12 resistance allele in Hua dbl2 was detected in a region containing
a homeologous non-reciprocal transposition (HNRT) from the resistance-containing portion of N2. This result suggests that
QTL in the N12.N2 HNRT enhanced the resistance of Hua dbl2 by increasing the dosage of resistance genes. The relationship
of QTL from different genetic backgrounds and their associations with other agronomic traits are discussed. 相似文献
15.
Mapping of Fhb2 on chromosome 6BS: a gene controlling Fusarium head blight field resistance in bread wheat (Triticum aestivum L.) 总被引:4,自引:0,他引:4
Cuthbert PA Somers DJ Brulé-Babel A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(3):429-437
Fusarium head blight (FHB) is one of the most important fungal wheat diseases worldwide. Understanding the genetics of FHB
resistance is key to facilitate the introgression of different FHB resistance genes into adapted wheat. The objective of this
project was to study the FHB resistance QTL on chromosome 6B, quantify the phenotypic variation, and qualitatively map the
resistance gene as a Mendelian factor. The FHB resistant parent BW278 (AC Domain*2/Sumai 3) was used as the source of the
resistance allele. A large recombinant inbred line (RIL) mapping population was developed from the cross BW278/AC Foremost.
The population segregated for three known FHB resistance QTL located on chromosomes 3BSc, 5A, and 6B. Molecular markers on
chromosome 6B (WMC104, WMC397, GWM219), 5A (GWM154, GWM304, WMC415), and 3BS (WMC78, GWM566, WMC527) were amplified on approximately
1,440 F2:7 RILs. The marker information was used to select 89 RILs that were fixed homozygous susceptible for the 3BSc and 5A FHB QTLs
and were recombinant in the 6B interval. Disease response was evaluated on 89 RILs and parental checks in the greenhouse and
field nurseries. Dual floret injection (DFI) was used in greenhouse trials to evaluate disease severity (DS). Macroconidial
spray inoculations were used in field nurseries conducted at two locations in southern Manitoba (Carman and Glenlea) over
two years 2003 and 2004, to evaluate disease incidence, disease severity, visual rating index, and Fusarium-damaged kernels.
The phenotypic distribution for all five-disease infection measurements was bimodal, with lines resembling either the resistant
or susceptible checks and parents. All of the four field traits for FHB resistance mapped qualitatively to a coincident position
on chromosome 6BS, flanked by GWM133 and GWM644, and is named Fhb2. The greenhouse-DS trait mapped 2 cM distal to Fhb2. Qualitative mapping of Fhb2 in wheat provides tightly linked markers that can reduce linkage drag associated with marker assisted selection of Fhb2 and aid the pyramiding of different resistance loci for wheat improvement. 相似文献
16.
Taguchi K Ogata N Kubo T Kawasaki S Mikami T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(2):227-234
Aphanomyces root rot, caused by Aphanomyces cochlioides Drechs., is one of the most serious diseases of sugar beet (Beta vulgaris L.). Identification and characterization of resistance genes is a major task in sugar beet breeding. To ensure the effectiveness
of marker-assisted screening for Aphanomyces root rot resistance, genetic analysis of mature plants’ phenotypic and molecular
markers’ segregation was carried out. At a highly infested field site, some 187 F2 and 66 F3 individuals, derived from a cross between lines ‘NK-310mm-O’ (highly resistant) and ‘NK-184mm-O’ (susceptible), were tested,
over two seasons, for their level of resistance to Aphanomyces root rot. This resistance was classified into six categories
according to the extent and intensity of whole plant symptoms. Simultaneously, two selected RAPD and 159 ‘NK-310mm-O’-coupled
AFLP were used in the construction of a linkage map of 695.7 cM. Each of nine resultant linkage groups was successfully anchored
to one of nine sugar beet chromosomes by incorporating 16 STS markers. Combining data for phenotype and molecular marker segregation,
a single QTL was identified on chromosome III. This QTL explained 20% of the variance in F2 population (in the year 2002) and 65% in F3 lines (2003), indicating that this QTL plays a major role in the Aphanomyces root rot resistance. This is the first report
of the genetic mapping of resistance to Aphanomyces-caused diseases in sugar beet. 相似文献
17.
R. Mizobuchi H. Sato S. Fukuoka S. Tsushima T. Imbe M. Yano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(9):2417-2425
Bacterial seedling rot (BSR), a destructive disease of rice (Oryza sativa L.), is caused by the bacterial pathogen Burkholderia glumae. To identify QTLs for resistance to BSR, we conducted a QTL analysis using chromosome segment substitution lines (CSSLs) derived from a cross between Nona Bokra (resistant) and Koshihikari (susceptible). Comparison of the levels of BSR in the CSSLs and their recurrent parent, Koshihikari, revealed that a region on chromosome 10 was associated with resistance. Further genetic analyses using an F5 population derived from a cross between a resistant CSSL and Koshihikari confirmed that a QTL for BSR resistance was located on the short arm of chromosome 10. The Nona Bokra allele was associated with resistance to BSR. Substitution mapping in the Koshihikari genetic background demonstrated that the QTL, here designated as qRBS1 (quantitative trait locus for RESISTANCE TO BACTERIAL SEEDLING ROT 1), was located in a 393-kb interval (based on the Nipponbare reference genome sequence) defined by simple sequence repeat markers RM24930 and RM24944. 相似文献
18.
Gubba Augustine Gonsalves Carol Stevens Mikel R. Tricoli David M. Gonsalves Dennis 《Molecular breeding : new strategies in plant improvement》2002,9(1):13-23
This study was undertaken to develop tomato plants with broad resistanceto tospoviruses which are a major limiting factor to tomato productionworldwide. A nontransgenic tomato line Stevens-Rodale (S-R), six transgenictomato lines expressing the nucleocapsid (N) protein gene of the lettuceisolate of tomato spotted wilt virus (TSWV-BL), and progeny of the crosses between S-Rand three of the transgenic lines homozygous for the N gene were evaluated fortheir resistance to tospovirus infection in greenhouse inoculation tests. S-Rhas the Sw-5 gene that confers resistance to several TSWVisolates. The six transgenic lines showed high levels of resistance wheninoculated with either TSWV-BL or a tomato isolate from Hawaii (TSWV-H).However, these same plants were highly susceptible to the Brazilian isolate ofgroundnut ringspot virus (GRSV-BR). Plants with the Sw-5gene were resistant to TSWV-BL and GRSV-BR, but were susceptible to TSWV-H.When inoculated with any of the three viruses, the F1 progeny of thecrosses exhibited a susceptible, tolerant, or resistant phenotype with a higherproportion of the plants being either tolerant or resistant. When F2progeny from F1 resistant plants of each cross were inoculated withany of the three viruses, a higher proportion of tolerant and resistant plantswas observed compared to the F1 progeny. Our results show thepotential to obtain broad resistance to tospoviruses by combining transgenicand natural resistance in a single plant. 相似文献
19.
Three interspecific crosses were developed using Cicer arietinum (ICC 4918) as the female parent and wild Cicer species [C. reticulatum - JM 2100, JM 2106 and C. echinospermum - ICCW 44] as the male parent. Cicer arietinum (ICC 4918) × C. reticulatum (JM 2100) cross produced the largest number of F2 plants and was chosen for linkage mapping using Random Amplified Polymorphic DNA (RAPD) primers. A partial linkage map was constructed based upon the segregation of 36 RAPD markers obtained by amplification using 35 primers. The linkage map consists of two linkage groups with 17 linked markers covering a total of 464.9 cM. Analyses also revealed association of three morphological traits with linked RAPD markers. Out of seven morphological traits tested for association with linked markers in the segregating plants, four Quantitative trait loci (QTL) were detected for the trait leaf length and three QTLs each for the traits leaf width and erect plant habit. 相似文献
20.
Detection and analysis of QTLs based on RAPD markers for polygenic resistance to Plasmodiophora brassicae Woron in Brassica oleracea L. 总被引:1,自引:0,他引:1
C. Grandclément G. Thomas 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(1-2):86-90
Resistance to Plasmodiophora brassicae Woron, the causal fungus of clubroot, was examined in an F2 population of a cross between a clubroot-resistant kale (Brassica oleracea L. var. acephala) and a susceptible cauliflower (Brassica oleracea L. var. botrytis). QTL detection was performed with RAPD markers. Two resistance notations, carried out at different times after inoculation, were used. Three markers were associated with these two notations and three were specifically linked to only one notation. QTL analysis suggests the existence of at least two genetic mechanisms implicated in the resistance phenomenon. 相似文献