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1.
Using monosomic lines of wheat cultivars ‘Palur’ and ‘Compal’ as recipient parents as well as disomic substitution lines of chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’, F3-populations and BC1′- to BC3′-populations with limited and free recombination of the 20 and 21 parental chromosomes, respectively, were realized and tested in field trials in comparison to the corresponding recipient cvs. ‘Palur’ and ‘Compal’. F3- and BC'-populations with the homozygous chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’ expressed higher and more stable grain protein values than the comparable populations with free recombination of the same chromosomes. The grain protein content of populations with limited recombination was significantly increased compared with the recipient cultivars. Some advantages of using intervarietal substitutions in wheat breeding are discussed.  相似文献   

2.
Inheritance of resistance to angular leaf spot (ALS) disease caused by Phaeoisariopsis griseola (Sacc.) Ferr was investigated in two common bean cultivars, Mexico 54 and BAT 332. Both Andean and Mesoamerican backgrounds were used to determine the stability of the resistance gene in each of the two cultivars. Resistance to P. griseola was phenotypically evaluated by artificial inoculation with one of the most widely distributed pathotypes, 63–39. Evaluation of the parental genotypes, F1, F2 and backcross populations revealed that the resistance to angular leaf spot in the cultivars Mexico 54 and BAT 332 to pathotype 63–39 is controlled by a single dominant gene, when both the Andean and Mesoamerican backgrounds were used. Allelism test showed that ALS resistance in Mexico 54 and BAT 332 to pathotype 63–39 was conditioned by the same resistance locus. Resistant and susceptible segregating populations generated using Mexico 54 resistant parent were selected for DNA extraction and amplification to check for the presence /absence of the SCAR OPN02 and RAPD OPE04 markers linked to the Phg-2 resistance gene. The results indicated that the SCAR OPN02 was not polymorphic in the study populations and therefore of limited application in selecting resistant genotypes in such populations. On the other hand, the RAPD OPE04 marker was observed in all resistant individuals and was absent in those scored susceptible based on virulence data. Use of the RAPD OPE04 marker in marker-assisted selection is underway.  相似文献   

3.
S. Singh    R. K. Gumber    N. Joshi    K. Singh 《Plant Breeding》2005,124(5):477-480
Interspecific hybridization is known to improve productivity and resistance to diseases in many crops. Therefore, an attempt was made to introgress productivity and disease resistance into chickpea from wild Cicer species. The true F1 hybrids of cultivated chickpea genotypes ‘L550’ and ‘FGK45’ with C. reticulatum were backcrossed twice to their cultivated female parents to minimize the linkage drag of undesirable wild traits. The pedigree method was followed to advance the segregating populations from straight crosses (without backcross) and BC1/BC2 generations to F5–F7. The interspecific derivatives recorded up to a 16.9% increase over the check cultivars and a 25.2% increase over the female parent in a preliminary yield evaluation trial. Of the 22 interspecific derivatives thus derived, four desi and two kabuli lines were further evaluated for seed yield in replicated trials at three diverse locations. These lines possess a high degree of resistance to wilt, foot rot and root rot diseases, and recorded a 6.1–17.0% seed yield increase over the best check cultivars.  相似文献   

4.
Inheritance of Karnal bunt-free trait in bread wheat   总被引：1，自引：0，他引：1  
A Karnal bunt (KB)‐free wheat stock (‘KBRL22’) obtained from a cross of two resistant lines (‘HD29’ and ‘W485’) was used as a donor to introgress the KB‐free trait into ‘PBW343’(an ‘Attila’ sib), the most widely grown wheat cultivar in India. The number of KB‐free and KB‐affected plants in BC 1, BC2, BC3 and BC4 as well the F2 was recorded after artificial inoculations. The segregation pattern in these generations clearly indicated two independently segregating, dominant genes which jointly confer the KB‐free attribute. The importance of the KB‐free line generated in this experiment is discussed.  相似文献   

5.
P.K. Singh    G.R. Hughes 《Plant Breeding》2006,125(3):206-210
Tan spot of wheat is caused by the fungus Pyrenophora tritici‐repentis. On susceptible hosts, P. tritici‐repentis induces two phenotypically distinct symptoms, tan necrosis and chlorosis. This fungus produces several toxins that induce tan necrosis and chlorosis symptoms in susceptible cultivars. The objectives of this study were to determine the inheritance of insensitivity to necrosis‐inducing culture filtrate of P. tritici‐repentis, race 2, and to establish the relationship between the host reaction to culture filtrate and spore inoculation with respect to the necrosis component. The F1, F2, and BC1F1 plants and F2:8 lines of five crosses involving resistant wheat genotypes ‘Erik’, ‘Red Chief’, and line 86ISMN 2137 with susceptible cultivars ‘Glenlea’ and ‘Kenyon’ were studied. Plants were spore‐inoculated at the two‐leaf stage. Four days later, the newly emerged uninoculated third leaf was infiltrated with a culture filtrate of isolate Ptr 92–164 (race 2). Reactions to the spore inoculation and the culture filtrate were recorded 8 days after spore inoculation. The segregation observed in the F2 and BC1F1 generations and the F2:8 lines of all crosses indicated that a single recessive gene controlled insensitivity to necrosis caused by culture filtrate. This gene also controlled resistance to necrosis induced by spore inoculation.  相似文献   

6.
The present study was carried out with the objective to validate the molecular markers, which have been previously reported to be linked to fertility restorer (Rf) gene(s) for WA-CMS lines of rice. Two mapping populations involving fertility restorer lines for WA-cytoplasm, viz., (i) an F2 population derived from the cross IR58025A/KMR3R consisting of 347 plants and (ii) a BC1F1 population derived from the cross IR62829A/IR10198R//IR62829A consisting of 130 plants were analyzed. Nine SSR and three CAPS markers reported to be linked to Rf genes along with two previously unreported SSR markers were analyzed in the mapping populations. In both the populations studied, the trait of fertility restoration was observed to be under digenic control. Eight SSR markers (RM6100, RM228, RM171, RM216, RM474, RM311, MRG4456 and pRf1&2) showed polymorphism between the parents of the F2 population, while the SSR markers RM6100 and RM474 showed polymorphism between the parents of both the F2 and BC1F1 populations. Only one CAPS marker, RG146FL/RL was polymorphic between the parents of the BC1F1 population. RM6100 was observed to be closely segregating with fertility restoration in both the mapping populations and was located at a distance of ~1.2 cM. The largest phenotypic variation was accounted for the region located between RM311 and RM6100. Using the marker-trait segregation data derived from analysis of both the mapping populations, a local linkage map of the genomic region around Rf-4, a major fertility restoration locus on Chromosome 10 was constructed, and RM6100 was observed to be very close to the gene at a distance of 1.2 cM. The accuracy of the marker RM6100 in predicting fertility restoration was validated in 21 restorers and 18 maintainers. RM6100 amplified the Rf-4 linked allele in a majority of the restorers with a selection accuracy of 94.87%. Through the present study, we have established the usefulness of the marker RM6100 in marker-assisted selection for fertility restoration in segregating populations and identification of restorers while screening rice germplasm for their fertility restoration ability.  相似文献   

7.
A new race F of broomrape overcomes all known resistance genes in cultivated sunflower, but recently, sources of resistance against race F have been developed. The objective of the present research was to study the inheritance of resistance to race F in crosses between 12 resistant sunflower breeding lines, derived from three different sources of resistance, and the susceptible male‐sterile line P‐21. Parental lines and F1, F2, F3 and BC1 generations were evaluated for broomrape resistance. Segregations in the F2 and BC1 to resistant parent approached resistant to susceptible ratios of 1: 15 and 1: 3, respectively, in most of the crosses, suggesting a double dominant epistasis. However, segregations of 3: 13 and 1: 1 for F2 and BC1, respectively, indicating a dominant‐recessive epistasis, were also found. The F3 data confirmed these results. Owing to the recessive nature of this resistance, it must be incorporated into both parental lines for developing resistant hybrid cultivars.  相似文献   

8.
本文报道了水稻第1染色体长臂上微效千粒重QTL qTGW1.2的验证和分解。针对前期qTGW1.2定位结果, 应用SSR标记检测, 从籼籼交组合珍汕973/密阳46衍生的1个BC2F7分离群体中, 筛选到杂合区间分别为RM11621-RM297和RM212-RM265的2个单株, 构建了两套BC2F8:9近等基因系, 将qTGW1.2进一步界定在RM212-RM265及其两侧交换区间的区域内。在此基础上, 筛选出5个在目标区间内分离片段缩小且呈阶梯状排列的单株, 衍生了5套BC2F10分离群体, 应用Windows QTL Cartographer 2.5进行QTL分析。结果表明, 每套群体均检测到千粒重QTL, 加性效应为0.13~0.38 g, 来自密阳46的等位基因提高千粒重; 经比较各个群体的分离区间, 将qTGW1.2分解为互引连锁的2个QTL, 其中, qTGW1.2a位于RM11730和RM11762之间934 kb的区域内, 呈加性作用, qTGW1.2b位于RM11800和RM11885之间2.1 Mb的区域内, 呈正向超显性。  相似文献   

9.
The wheat progenitors and other wild relatives continue to be important sources of genes for agronomically desirable traits, which can be transferred into durum wheat (Triticum turgidum; 2n = 4x = 28; AABB genomes) cultivars via hybridization. Chromosome pairing in durum × alien species hybrids provides an understanding of genomic relationships, which is useful in planning alien gene introgression strategies. Two durum cultivars, ‘Lloyd’ and ‘Langdon’, were crossed with diploid wheatgrass, Thinopyrum bessarabicum (2n = 2x = 14; JJ), to synthesize F1 hybrids (2n = 3x = 21; ABJ) with Ph1. ‘Langdon’ disomic substitution 5D(5B) was used as a female parent to produce F1 hybrids without Ph1, which resulted in elevation of pairing between durum and grass chromosomes – an important feature from the breeding standpoint. The F1 hybrids were backcrossed to respective parental cultivars and BC1 progenies were raised. ‘Langdon’ 5D(5B) substitution × Th. bessarabicum F1 hybrids were crossed with normal ‘Langdon’ to obtain BC1 progeny. Chromosome pairing relationships were studied in F1 hybrids and BC1 progenies using both conventional staining and fluorescent genomic in situ hybridization (fl‐GISH) techniques. Multicolour fl‐GISH was standardized for characterizing the nature and specificity of chromosome pairing: A–B, A–J and B–J pairing. The A–J and B–J pairing will facilitate gene introgression in durum wheat. Multicolour fl‐GISH will help in characterizing alien chromosome segments captured in the durum complement and in their location in the A and/or B genome, thereby accelerating chromosome engineering research.  相似文献   

10.
Genetic studies were conducted on nine triticale cultivars and lines lo determine the presence and identity of stem rust resistance genes. The lines were intercrossed and their F2 and F3 generations were tested with selected pathotypes of Puccinia graminis tritici. Segregation in seedling tesis showed the presence of two new genes SrLal and SrLa2 in ‘Lasko’, SrBj anil SrJ in ‘Bejon’. SrVen in ‘Currency’, SrBj in ‘Abacus’ and ‘RM4’ and SrNin in ‘Tahara’, ‘Maidan’ and ‘Madonna’ SrBj, SrNin, SrLal and SrLa2 were genetically independent and each conferred resistance to the currently important Australian P. graminis tritici pt 34-2.12.13, whereas SrJ and SrVen conferred moderately susceptible reactions to the same pathotype. SrVen segregated independently of SrBj, but the relationship of SrVen with the other genes was noi determined. The typical low infection types conferred by SrBj and SrJ were best expressed at temperatures above 21 C, Prolamine separations nsinj; sodium dodecyl sulphate-polyacrylamide gel elcclrophoresis confirmed that SiNin and SrBj were located in chromosome 2R. The gene SrLal behaved as a third allele at or near the Sr27, SrSatu locus in chromosome 3R, The present work demonstrated that chromosomes 2R and 3R are important bearers of genes Tor stem rust resistance in hexaploid iriticale.  相似文献   

11.
The present research aimed to study the inheritance and chromosomal location of a photoperiod‐thermo sensitive male sterility (PTSMS) gene in Xinong 291S (XN291S), which is a new PTSMS wheat line. The inheritance was studied in F1 and F2 populations derived from crosses between XN291S and eight wheat cultivars. All F1 plants were fertile and the F2 populations segregated in either 15 : 1 or 3 : 1 fertile : sterile ratios indicating that PTSMS was controlled by one or two recessive major genes. Five wheat cultivars carried homozygous dominant alleles for fertility, whereas the other three, including ‘Chinese Spring’ (CS), carried a single homozygous dominant allele. Chromosomal location of the PTSMS gene was studied by crossing a set of CS nulli‐tetrasomic lines to XN291S. Self‐fertility of F1 hybrids XN291S/N5BT5A and XN291S/N5BT5D were significantly lower than the others. Therefore, the PTSMS gene in XN291S that differed from CS was located on chromosome 5B. Location of the second PTSMS gene needs further study.  相似文献   

12.
A study was conducted under controlled environment conditions in a phytotron to determine the nature of the inheritance of resistance Helminthosporium leaf blight (HLB) in a synthetic hexaploid wheat line, ‘Chirya‐3’, against the isolate KL‐8 of Bipolaris sorokiniana from the major wheat growing region of India. Crosses were made between two susceptible lines ‘WH 147’ and ‘Chinese Spring’. Analyses of F1 and F2 populations of these two crosses (‘WH 147’בChirya‐3’ and ‘Chinese Spring’בChirya‐3’) showed that resistance against the isolate in ‘Chirya‐3’ was governed by two recessive genes functioning in a complementary interaction giving an F2 segregation pattern of 1 : 15 (resistant : susceptible). The segregation pattern of the resistant F2 progenies in F3 families from both crosses confirmed that two homozygous recessive genes were responsible for resistance to the isolate of Bipolaris sorokiniana in the synthetic line ‘Chirya‐3’. It is proposed that the genes be designated as hlbr1 and hlbr2.  相似文献   

13.
M. Confalonieri    R. Bollini    N. Berardo    A. Vitale  A. Allavena 《Plant Breeding》1992,109(4):329-334
The abundant lectin phytohemagglutinin (10 % of total seed protein) does not contain sulfur amino acids and, being a potent antimetabolite, it is responsible for the lowering of the nutritional value of bean seeds. The aim of the present work was to improve the dry bean cultivar ‘Taylor's Horticultural’ (Asgrow), by genetically introducing the lectin null (lec/lec) character from two null genotypes: ‘Pinto UI 111’ and ‘Heidi’. Thirty-seven BC2F3 and fourteen BC6F5 inbred lines were evaluated in agronomical trials. Analysis of Variance (ANOVA) showed significant differences among BC2F3 breedings lines for all traits under evaluation. Comparison of the LedLee genotypes versus lec/lec did not show statistically significant differences in the means for the following traits: yield, yield components and percentage of protein in the seed. Fourteen BC6F5 lines, compared together with their recurrent parent ‘Taylor's Horticultural’, showed significant differences among genotypes for 1000 seed weight, protein percentage on dry matter and ash percentage. No significant differences were observed for grain yield. The data indicate that lectin removal did not have a detrimental effect on the traits evaluated.  相似文献   

14.
According to our previous investigations, resistance to Phytophthora capsid in Capsicum annuum genotypes, ‘Line 29’, ‘PI201232’, ‘PI201234’ and Serrano Criollo de Morelos 334 (‘SCM334’), seems to be controlled by three genes. In order to determine the genie relationships between these four sources of resistance, three experiments were conducted which included the four genotypes, their F1s, F2s, F3s and BC1 generations together with the susceptible pepper genotype ‘Morron INI A 224’. Inoculations were made, when plants had 4—6 leaves, by irrigating the culture substrate with a zoospore suspension of P. capsici isolate ‘Bl’. Though the four genotypes showed percentages of resistance close to a 100%, none of them actually reached this level in the three experiments. ‘SCM334’ was the most resistant genotype, transmitting a high level of resistance to its F1, F2 and BQ generations. ‘Line 29’ was more resistant than ‘PI201232’ and ‘PI201234’. However, the F1 F2 and BQ generations of these three lines showed similar degrees of resistance. The four genotypes seem to have one of the three genes postulated for their resistance in common. All genes displayed a similar level of resistance, except the specific genes of ‘SCM334’, the effect of which was slightly higher. Several working procedures are suggested for breeding programmes.  相似文献   

15.
We constructed a high‐resolution physical map for the qSPP7 QTL for spikelets per panicle (SPP) on rice chromosome 7 across a 28.6‐kb region containing four predicted genes. Using a series of BC7F4 near‐isogenic lines (NILs) derived from a cross between the Korean japonica cultivar ‘Hwaseongbyeo’ and Oryza minuta (IRGC Acc. No. 101144), three QTLs for the number of SPP, grains per panicle and primary branches were identified in the cluster (P ≤ 0.01). All three QTLs were additive, and alleles from the O. minuta parent were beneficial in the ‘Hwaseongbyeo’ background. qSPP7 was mapped to a 28.6‐kb region between the two simple sequence repeat (SSR) markers RM4952 and RM21605. The additive effect of the O. minuta allele at qSPP7 was 23 SPP, and 43.6% of the phenotypic variance was explained by the segregation of the SSR marker RM4952. Colocalization of the three QTLs suggested that this locus was associated with panicle structure and had pleiotropic effects. The NIL populations and molecular markers are useful for cloning qspp7.  相似文献   

16.
Long-term resistance to rust diseases depends on the identification and use of durable resistance sources or on the continuing use of new resistances and combinations of genes for specific resistance. These studies include four Australian wheats with intermediate, but inadequate levels of resistance and a French wheat ‘Hybride-de-Bersée’ (‘Bersee’), with reputed durable resistance to stripe rust. Studies of F2 and F3 populations from crosses with the susceptible ‘Avocet’ indicated that intermediate levels of adult plant stripe rust resistance in cultivars ‘Harrier’, ‘Flinders’ and ‘M2435’ were inherited monogenically, whereas King possessed two genes for resistance. Cultivars Harrier and M2435 possessed the same gene. Similarly, cvs. King and Flinders carried a gene in common. Like ‘Harrier’ and ‘M2435’, ‘King’ and ‘Flinders’ share common parents. The higher level of resistance in ‘Bersee’ was controlled by four genes. This conclusion was based on conventional genetic analysis, tests on F2-derived F7 single-seed descent lines and testcross progenies.  相似文献   

17.
Triticum tauschii provides breeders with a valuable source of resistance and tolerance genes. Elucidation of the inheritance of traits in this species that hinder its use in breeding programmes is therefore of interest to wheat breeders. Inheritance of threshability was investigated in the crosses of four non-free-threshing (NFT) synthetic hexaploids (Triticum turgidum×T. tauschii) and two free-threshing (FT) T. aestivum cultivars during four crop seasons over 3 years at E1 Batan and Ciudad Obregon, Mexico. The parents, their F1 Hybrids and individual F2 plant-derived F3 progenies of the crosses revealed that ‘Altar 84’/T. tauschii (219), ‘Chen’/T. tauschii (205), ‘Chen’/T. tauschii (224), and ‘Duergand’/T. tauschii (214) have independently segregating loci with two dominant alleles controlling threshability. Intercrosses among the synthetics, except ‘Altar 84’/T. tauschii (219), showed the genes to be allelic to each other. The cross between the FT cultivars showed no segregation in the F3 generation, indicating common recessive genes. Based on these findings, population sizes of the synthetic-derived breeding materials should be increased to improve the chances of selecting FT desirable plants in the programme.  相似文献   

18.
Several upland Japonica breeding lines, WAB450-11-1-3-P40-HB (Abbreviated as WAB450-11), WAB450-11-1-2-P61-HB (WAB450-13), WAB450-l-B-P-91-HB (WAB450-14), IRAT216, IRAT359, and IRAT104, possessing restoring ability for the Dian 1 type cms (cms-D) line Dianyu 1A were recently identified at Food Crops Research Institute, Yunnan Academy of Agricultural Sciences, P. R. China. In this study, the inheritance of restoring ability in these lines was characterized through the production of backcross populations to the male-sterile and maintainer Dianyu 1 lines. Each of the restorer lines was used to pollinate Dianyu 1A to form a F1 hybrid which was then backcrossed (1) with Dianyu 1B producing a BC1F1 population and (2) to the female parent Dianyu 1A producing a BC5F2 population. The lines were also crossed with the japonica restorer line C57, carrying the restorer gene Rf1 that was introgressed from indica, to form F1 hybrids, these hybrids were then testcrossed with Dianyu 1A to study the allelic relationship of their restorer genes to Rf1. The inheritance in these testcross populations indicated that the complete restoring ability of WAB450-11, WAB450-13, WAB450-14, IRAT216, IRAT359, and the partial restoring ability of IRAT104 were controlled by dominant genes, and the gene in WAB450-13, WAB450-14, and IRAT216 was allelic or identical to Rf1. When 136 SSR markers were used to score 143 BC1F1 individuals from Dianyu 1A/WAB450-13//Dianyu 1B, the japonica Rf1 allele was found to be located between RM171 and RM6100 on the long arm of chromosome 10, an interval corresponding to that known for the indica Rf1 allele. The distance between RM171 and Rf1 is 2.8 cM, and that between Rf1 and RM6100 is 4.9 cM. Similar linkage results were obtained from mapping 89 individuals of the corresponding BC5F2 population (Dianyu 1A/6/Dianyu 1A/WAB450-13).  相似文献   

19.
Interspecific hybridization between foxtail millet cultivars (Setaria italica) and a green foxtail (S. viridis) resistant to the herbicide sethoxydim were undertaken to breed foxtail millet for improved herbicide resistance. Parents, reciprocal F1 hybrids, F2 selfed derived populations and BC1 backcross progeny were produced and analysed for mortality and fresh weight over a range of dosages. All resistant progeny were 700 times more resistant than susceptible cultivars and was symptom free under current field dosages. Segregations of resistant and susceptible progeny (3:1 in F2 and 1:1 in BC1) were not dependent upon dosage. Heterozygous individuals displayed the same magnitude of resistance as homozygous plants at twelve times the recommended field dosage. Results suggested that sethoxydim resistance in foxtail millet was controlled by a single, completely dominant, nuclear gene. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
This work reports a gene pyramiding approach assisted by DNA markers used to develop “carioca” seeded common bean (Phaseolus vulgaris L.) elite lines harboring three different rust resistance genes. Rust is among the most destructive diseases that attack P. vulgaris and cause serious damage worldwide. The rust resistance genes Ur-5 (from ‘Mexico 309’), Ur-11 (from ‘BelMiDak RR-3’), and Ur-14 (from ‘BRS Pioneiro’, a “carioca” seeded cultivar derived from the resistance source ‘Ouro Negro’) were combined in the “carioca” seeded bean cultivar ‘Rudá’. Firstly, two different backcross programs were conducted separately to produce progenies harboring individually the Ur-5 and Ur-11 genes. Molecular fingerprinting analysis was used to select plants genetically similar to ‘Rudá’ in the backcross cycles to accelerate the recurrent-background recovery. The obtained progenies were initially intercrossed and then crossed with ‘BRSMG Pioneiro’ (Ur-14). The final F1 plants derived from these crosses were screened with DNA markers linked to the three rust resistance genes: SI19 (Ur-5), SAE19 (Ur-11) and OPX11 (Ur-14). The plants selected as harboring all the alleles of interest were used to obtain the next generations. The selection based on DNA markers was conducted up to the F4:5 generation. We were able to select F4:7 progenies showing all the DNA markers associated to the genes of interest and resistant to all specific races of U. appendiculatus used for phenotypically detecting each one of the rust resistance genes. Yield evaluations show that these selected lines are as productive as the recurrent parent ‘Rudá’ and high-performing control cultivars grown in Brazil.  相似文献   

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