Heritability and gain from selection for field resistance against multiple root-knot nematode species (Meloidogyne incognita race 1 and M. javanica) in carrot

Heritability and gain from selection of traits associated with field resistance to multiple root-knot nematode species were estimated in carrot (Daucus carota L.). Experimental plots were uniformly and simultaneously infested with Meloidogyne incognita race 1 and M. javanica. Forty-seven half-sib families derived from the cv. ‘Brasília’ were evaluated for: (1) percentage of commercial roots with non-galling symptoms (%RNG); (2) percentage of commercial roots with gall symptoms (%RGS) and (3) percentage of non-commercial roots (%NCR). The cultivars ‘Brasília’ (resistant), ‘Carandaí’ (intermediate) and ‘Nova Kuroda’ (susceptible) were employed as standards. Broad-sense heritability estimates were 61.9 % for %RNG; 30.6 % for %RGS and 67.9 % for %NCR. However, the gains from selection were very small for all traits. The genotypic correlation between %RGS and %NCR was –0.38 and the correlation between %RNG and %RGS was 0.13. Selection on increasing %RNG resulted in a negative correlated response on %NCR (genotypic correlation = –0.99) indicating repulsion phase linkage(s) between the genetic factor(s) controlling these traits. The phenotypic correlation of –0.88 between %RNG and %NCR suggested that incomplete penetrance and dosage effects might be involved in the expression of these traits. Selection of superior genotypes (i.e. high %RNG, low %RGS, and low %NCR) can be achieved. ‘Brasília’ was among the genotypes selected for the following cycle of recombination reinforcing the notion that this cultivar is one of the most promising sources of stable, wide-spectrum field resistance to Meloidogyne species in D. carota. This revised version was published online in July 2006 with corrections to the Cover Date.     

Resistance to melon vine decline derived from Cucumis melo ssp. agrestis: genetic analysis of root structure and root response

Melon vine decline is a major soilborne disease that causes severe economic losses around the world. The fungal pathogens Monosporascus cannonballus Pollack et Uecker and Acremonium cucurbitacearum Alfaro‐García, W. Gams et J. García‐Jiménez have been reported as the main causal agents of this disease. A relatively high level of resistance has been reported in Cucumis melo L. ssp. agrestis (Naud.) Pangalo in the Asiatic accession Pat 81. Although specific resistance mechanisms controlling pathogen‐induced root lesions have been characterized in Pat 81, the development of a vigorous and branched root system can also appreciably increase its tolerance to vine collapse. The genetics of root traits related to root vigour and structure were studied in the progeny derived from a cross between Pat 81 and the highly susceptible cultivar ‘Piñonet’ market class ‘Piel de Sapo’(C. melo L. ssp. melo). The inheritance of specific resistance to soilborne fungi was also studied by analysing root response to inoculation employing naturally infested soil. Estimates of the broad‐(H) and narrow‐sense (h²) heritabilities indicated that the majority of the variation for lesion resistance in lateral and fine roots, in the root weight, root length, and the root surface area could be explained by additive effects, whereas dominance is important in plant biomass and resistance to lesions in hypocotyls. Selection for improved root systems conferring resistance and tolerance to vine decline was successfully conducted in BC₁ progeny derived from a Pat 81 בPiñonet’ mating. Moderate values of heritabilities (0.03–0.76) suggest that breeding strategies that combine family and individual selection could enhance genetic progress. As some of the traits analysed exhibited heterosis, breeding methods directed towards recovering hybrid vigour may increase gain from selection.     

Characterization and inheritance of partial resistance to downy mildew, Peronospora parasitica, in breeding material of broccoli, Brassica oleracea convar. botrytis var. italica

Twenty doubled haploid broccoli lines from breeding material were evaluated for resistance to Peronospora parasitica at the seedling stage. All lines supported sporulation of the pathogen but to varying extents and intensities. Partial resistance of the more resistant lines,‘br8’and ‘br9′, reduced conidia production on cotyledons by 50-70% compared with the most susceptible lines. Inoculation of the two most resistant lines with 13 isolates of different geographical origins revealed that ‘br9′, showed a rather uniform level of resistance to all isolates while ‘br8’showed some isolate specificity Partial resistance was evaluated in six of the broccoli lines in a half diallel set of crosses. Disease assessment of seedlings showed that additive genetic effects explained 45.8% and 31.8% of the total variation of sporulation score and conidia production, respectively This suggests that recurrent selection for partial resistance to P. parasitica in early generation in breds or in populations of broccoli will be efficient to obtain cotyledon resistance.     

'Francolí', a late flowering almond cultivar re-classified as self-compatible

To verify the compatibility behaviour of the almond cultivar ‘Francolí’ and to clarify its S genotype a combination of pollination tests, stylar ribonuclease and allele specific PCR analysis was used. ‘Francolí’ was released from IRTA's breeding programme in 1994, having been putatively raised from the cross ‘Cristomorto’ (S₁S₂) × ‘Gabaix’ (S₁₀S₂₅). This cultivar was also reported to be self‐incompatible but revealing only one S band in the zymograms after S‐RNases analysis. ‘Francolí’ sets nuts after test crossing with two S₁S₂₅ cultivars, having a different genotype from that earlier reported. ‘Francolí’ was also observed to be self‐compatible after selfing flowers in the field and in the laboratory. ‘Francolí’ was re‐assigned the S₁S_f genotype after test crossing, stylar ribonuclease and PCR data analysis. After microsatellite analysis, the self‐compatible ‘Tuono’ (S₁S_f) cultivar is suggested as the male parent of ‘Francolí’ instead of the earlier reported ‘Gabaix’.     

Genetic variability and heritability estimates for hardseededness and flowering in balansa clover (Trifolium michelianum Savi) populations

Suitability of annual pasture legume species like balansa clover (Trifolium michelianum Savi) in southern Australian farming systems depends on their hardseededness and time to flowering. Late maturing varieties with increased rate of hardseed breakdown, particularly in the late summer—early autumn period are desirable to ensure reliable regeneration in permanent pastures. Two half-sib family balansa clover populations were used to estimate heritability for the rate of breakdown of hardseededness and time to flowering. High narrow-sense heritability estimates (90.5–96.1%, rate of hardseed breakdown; 85.9–94.5%, time to flowering) were obtained, and were mainly attributed to additive gene effects. There was no relationship between rate of hardseed breakdown and time to flowering in Group1 half-sib family, which indicated that selection for both traits could be undertaken independently. In half-sib family Group 2 the relationship between the two traits suggested the possibility of selecting late maturing cultivars with increased rate of hardseed breakdown. Significant differences in time to flowering and rate of hardseed breakdown both within and between the two half-sib family groups suggested that phenotypic recurrent selection would be effective in improving the traits in these populations.     

Backcross breeding for improved resistance to common bacterial blight in pinto bean (Phaseolus vulgaris L.)

Common bacterial blight (CBB) caused by Xanthomonas campestris pv. phaseoli reduces common bean (Phaseolus vulgaris L.) yield and quality worldwide. Genetic resistance provides effective disease control; however. a high level of resistance is difficult to attain and does not exist in pinto bean, the most important dry bean market class in North America. Our objective was to determine if a backcross breeding approach with the aid of molecular markers linked to quantitative trait loci (QTL) for resistance to CBB in a donor parent could be used to attain higher levels of resistance to CBB in pinto bean. QTL conditioning CBB resistance from the donor parent XAN 159 were introgressed into the recurrent parent‘Chase’using classical backcross breeding and intermittent marker‐assisted selection.‘Chase’pinto bean is moderately resistant and the breeding line XAN 159 is highly resistant to Xanthomonas campestris. Marker assays confirmed the presence of independent QTL from GN no. 1 Sel 27 and XAN 159 in advanced backcross‐derived pinto bean lines with improved CBB resistance. Agronomic characteristics of‘Chase’were fully recovered in the backcross‐derived lines. An important QTL for CBB resistance from XAN 159 on linkage group B6 was not introgressed because tight linkage between this QTL and the dominant V allele that causes an unacceptable black‐mottled seed coat colour pattern in pinto bean could not be broken.     

Validation of a major QTL for scab resistance with SSR markers and use of marker-assisted selection in wheat

The objectives of this study were to validate the major quantitative trait locus (QTL) for scab resistance on the short arm of chromosome 3B in bread wheat and to isolate near‐isogenic lines for this QTL using marker‐assisted selection (MAS). Two resistant by susceptible populations, both using ‘Ning7840’ as the source of resistance, were developed to examine the effect of the 3BS QTL in different genetic backgrounds. Data for scab resistance and simple sequence repeat (SSR) markers linked to the resistance QTL were analyzed in the F_2:3 lines of one population and in the F_3:4 lines of the other. Markers linked to the major QTL on chromosome 3BS in the original mapping population (‘Ning7840’/‘Clark’) were closely associated with scab resistance in both validation populations. Marker‐assisted selection for the QTL with the SSR markers combined with phenotypic selection was more effective than selection based solely on phenotypic evaluation in early generations. Marker‐assisted selection of the major QTL during the seedling stage plus phenotypic selection after flowering effectively identified scab resistant lines in this experiment. Near‐isogenic lines for this 3BS QTL were isolated from the F₆ generation of the cross ‘Ning7840’/‘IL89‐7978’ based on two flanking SSR markers, Xgwm389 and Xbarc147. Based on these results, MAS for the major scab resistance QTL can improve selection efficiency and may facilitate stacking of scab resistance genes from different sources.     

Inheritance of White Rust Resistance in Brassica juncea

Inheritance of white rust resistance was studied in two crosses between resistant (R) and sensitive (S) types of Brassica juncea, namely EC 12749 בParkash’ (R × S) and EC 12749 בVaruna’ (R × S) under conditions of normal and late sowing. Analysis of six generations revealed the importance of additive, dominant and epistatic effects. Disease was more prevalent under late sowing due to favourable environment. Reciprocal recurrent selection is advocated for exploiting the additive and non-additive gene effects for resistance to white rust.     

Combining ability for beet armyworm, Spodoptera exigua, resistance and horticultural traits of selected Lycopersicon pennellii-derived inbred backcross lines of tomato

Ten selected inbred backcross lines (IBL), from a Lycopersicon esculentum cv.‘Peto 84’×Lycopersicon pennellii IBL population, with resistance to beet armyworm (BAW), Spodoptera exigua, higher fruit mass and fruit yield, were crossed with eight elite cultivated L. esculentum inbred lines in a Design II mating design. Three elite inbreds were also crossed to ‘Peto 84′, the IBL recurrent parent, as a control for combining ability. Field plots of all resulting F₁ progenies and control cultivars were inoculated with BAW eggs and evaluated for resistance to BAW, fruit mass, fruit yield, vine size and maturity at three field locations. Reductions in fruit damage by BAW were found in four of the 10 IBL F₁ progenies. Significant male and female general combining ability (GCA) estimates for BAW resistance were observed, but significant specific combining ability for BAW resistance was not detected. The fruit mass of F₁ hybrids was significantly lower than large-fruited controls, but was not significantly different from elite inbred by ‘Peto 95’F₁ hybrids. Selection based on inbred performance identified IBL with positive GCA for BAW resistance and yields in Design II hybrids. BAW resistance in the 09 selected IBL and IBL- derived F₁ progeny was associated with two undesirable traits, later maturity and larger vine size. Index selection of IBL was more effective at identifying IBL with positive GCA for fruit mass and fruit yield than GCA for BAW resistance.     

Mapping of quantitative trait loci conferring resistance to bacterial wilt in tobacco (Nicotiana tabacum L.)

Tobacco bacterial wilt (TBW) is one of the most serious tobacco diseases in the world. Studies have shown that tobacco resistance to TBW is quantitatively inherited. This study aimed to map quantitative trait loci (QTL) conferring TBW resistance. An F_2 : 3 population containing 237 lines was developed from a cross between two flue‐cured tobacco cultivars, ‘Yanyan 97’ (YY97; moderately resistant to TBW) and ‘Honghua Dajinyuan’ (HD; highly susceptible to TBW), and a linkage map consisting of 201 simple sequence repeats (SSR) markers and spanning a total length of 2326.7 cM was constructed based on the population. Field experiments were conducted 2011 and 2012, and disease symptoms were investigated three times in each year. The phenotypic data were analysed either separately or jointly for QTL mapping using the software QTLNetwork 2.1. Eight QTL with significant main effects were mapped on chromosomes 2, 6, 12, 17 and 24. A major QTL (qBWR17a) was detected on chromosome 17, which explained up to 30% of the phenotypic variation. The results can facilitate marker‐assisted selection (MAS) in TBW resistance breeding programme.     

Reciprocal recurrent selection in maize enhances heterosis and ears yield

The objective of the research was to evaluate recurrent selection strategies in maize (Zea mays L.) by determining the expected and realized responses to selection, as well as the alterations in heterosis, of hybrids from the cross between the original populations (C0) and the third cycle (C3). The genetic variances and covariances were obtained for intrapopulational (P₁₁ and P₂₂) and interpopulational (P₁₂ and P₂₁) half-sib progenies from populations 1 and 2 in cycles C0 and C3. One-hundred progenies of each type were evaluated [husked ear weight (g plant^?1)] at two separate locations by conducting 10 × 10 triple lattice design experiments contiguous for each cycle. Four different recurrent selection strategies were investigated: reciprocal recurrent selection (RRS), interpopulation testcross half-sib selection (THS 1 and THS 2) and intrapopulational half-sib recurrent selection (HSS). THS 1, which employed population 1 (with the lowest frequency of favorable alleles) as tester, was most efficient in the simultaneous improvement of the hybrid and the two populations per se. RRS showed the highest efficiency in improving the interpopulational hybrid but not in the parental populations. In order to estimate heterosis and realized responses to RRS, representative samples of seed from intra and inter-populational half-sib progenies from C0 and C3 were employed in randomized block design experiments with 10 repetitions carried out at two separate locations. RRS increased heterosis in the interpopulational hybrid from 12.3 % (C0) to 24.9 % (C3), and the productivity gain [husked ear weight (t ha^?1)] was 13.5 % over the three cycles.     

Association of Eyespot Resistance in Wheat cv. 'Cappelle-Desprez' with Endopeptidase Profile

To test for the association of the eyespot of wheat cv. ‘Cappelle-Desprez’ with the structural gene encoding the isozyme Ep-A1, F₃, families from the cross ‘Cappelle-Desprez’ (resistant) X ‘Chinese Spring’ (susceptible) were selected on the basis of endopeptidase phenotype. Analysis of eyespot reaction showed that Ep-Alb homozygotes were associated with a higher level of resistance than Ep-Al a homozygotes. Thus selection of the Ep-Alb allelc should assure concurrent selection of at least a part of the eyespot resistance of ‘Cappelle-Desprez’.     

A new locus for resistance to brown planthopper identified in the indica rice variety DV85

The brown planthopper (BPH) is one of the most destructive insect pests of rice. Resistant varieties have proved to be one of the most economic and effective measures for BPH management. In this study, an indica rice ‘DV85’ showed resistance to biotype 2 of BPH by bulked seedling test, and a recombinant inbred line (RIL) population derived from a cross between a susceptible rice ‘Kinmaze’ and ‘DV85’ was phenotyped to map genetic factors conferring BPH resistance in ‘DV85′. Composite interval mapping revealed that one quantitative trait locus (QTL) with a LOD score of 10.1 was detected between XNpb202 and C1172 on chromosome 11. This QTL was designated as Qbph11. Qbph11 explained 68.4% of the phenotypic variance of BPH resistance in this population. The allele from the resistant parent ‘DV85’ at Qbph11 reduced the damage caused by BPH feeding and would be very useful in breeding resistant rice varieties via marker‐assisted selection.     

Integrating marker assisted background analysis with foreground selection for identification of superior bacterial blight resistant recombinants in Basmati rice

Basmati rice is highly susceptible to bacterial blight (BB) caused by Xanthomonas oryzae pv. oryzae. Transfer of BB resistance genes from non‐Basmati sources to Basmati through cross‐hybridization requires strict monitoring for recovery of the desirable Basmati quality traits in the recombinants, which show complex inheritance pattern. We integrated background analysis using mapped microsatellite markers with foreground selection to identify superior lines that combine useful genes from a non‐Basmati BB resistance donor line IRBB55 with grain and cooking quality characteristics of the popular Basmati rice variety ‘Pusa Basmati 1’ (PB 1) employing backcross pedigree strategy. Foreground selection using linked markers ensured presence of two genes, xa13 and Xa21 for BB resistance from IRBB55, and the recurrent parent PB 1 allele for the waxy locus giving intermediate amylose content and maintainer allele at fertility restorer locus in the BC₁F₅ recombinants. Background analysis enabled selection of recombinants with recurrent parent genome to the extent of 86.3% along with the quality traits. The extent of introgression of non‐Basmati donor chromosome segments in the superior selections was estimated to be < 7.8 Mb and < 6.7 Mb in the xa13 and Xa21 linked genomic regions, respectively. Association mapping identified three quantitative trait loci, one each for 1000‐grain weight, fertile grains/panicle and cooked kernel length. The backcross‐pedigree breeding strategy facilitated recovery of additional desirable characteristics from the donor in some of the selections. The elite selection Pusa 1460‐01‐32‐6‐7‐67 with maximum genomic background and quality characteristics of the recurrent Basmati parent gave resistance reaction against BB, similar to that of the non‐Basmati resistant check variety and recorded an yield advantage of 11.9% over the best check in the multiplication agronomic trial in the Basmati growing region of India. This line, which has been released as a new variety in the name of ‘Improved Pusa Basmati 1’ for commercial cultivation in India, is an example of successful application of marker assisted selection to variety development.     

Frequencies of Vertical Resistances and Virulences in the Rye-Powdery Mildew Pathosystem*

Nine populations of rye (Secale cereale L.; the cultivars ‘Kustro’, ‘Danko’ and ‘Carokurz’. a breeding population PA 14/75 and five Iranian primitive ryes) were tested with three or two pathotypes of powder)’ mildew (Erysiphe graminis DC. f. sp. secalis Marchal) to determine the frequencies of vertical resistances. Similarly, three populations of powder)’ mildew isolated from the above eultivars were tested with two rye pathodemes to estimate the frequencies of vertical virulences. Tests were carried out on leaf segments cultivated in vitro. To explain the pattern of the host-parasite interaction, a model with at least four resistance and virulence genes was required. In the rye populations the genotypes of most plants could be determined unambiguously whereas in the powdery mildew populations no unique classification of one-postule isolates was possible due to the limited number of rye differentials. Both the host and the pathogen populations were polymorphic for resistance and virulence, respectively. In all lye populations except PA 14/75 the resistance frequencies were low. In the mildew populations the virulence frequencies were high and complex races occurred rather frequently. The virulence frequencies were related to the resistance frequencies of the respective host population. Results were compared with mathematical host-parasite models accounting for gene-for-gene interaction and balancing natural selection. Observations agree well with theory.     

Early selection for extreme resistance to potato virus Y and tobacco etch virus in potato using a β-glucuronidase-tagged virus

The Ry_sto gene from Solanum stoloniferum introduced into potato cultivars (Solanum tuberosum L. ssp. tuberosum) confers resistance to potato virus A, potato virus V and potato virus Y (PVY). In addition to PVY, tobacco etch virus (TEV) and a TEV construct that encodes β‐glucuronidase (TEV‐GUS) were inoculated to determine the inheritance of resistance to these viruses in progenies obtained from potato cultivars containing the Ry_sto gene. While cultivars ‘Karlena’ and ‘Delikat’ were susceptible, ‘Bettina’ and clone 927eY were resistant to PVY, TEV and TEV‐GUS, as determined by enzyme linked immunosorbent assay, biotest and GUS assay, respectively. The segregation ratios obtained from the progenies of ‘Bettina’בDelikat’ and 816eY בKarlena’ indicate that resistances to PVY and TEV are governed by one dominant gene or two genes tightly linked in coupling phase. Evidently, Ry_sto confers broad spectrum resistance to potyviruses. TEV resistance could be reliably detected 4 days after inoculation with the TEV‐GUS construct by GUS assay. Therefore, the GUS‐tagged TEV construct can be used for early selection for resistances based on the gene Ry_sto or closely linked genes.     

Kale population improvement and cultivar production

Marrow-stem kale (Brassica oleracea var. acephala L.) is grown in the United Kingdom, New Zealand and similar climates, for feeding cattle and sheep during autumn and winter. Population improvement by half-sib family selection for higher digestibility and digestible organic matter yield, lower levels of antimetabolites, and clubroot resistance is described and analysed as a selection experiment. The foundation population consisted of 120 clubroot resistant plants from the 16 most resistant marrow-stem cultivars in an assessment of 96 cultivars of Brassica oleracea. At the end of the first generation of selection adequate resistance had been achieved. After five generations, dry-matter content and digestible organic matter yield had been increased, the latter without an undesirable increase in height. Indolyl glucosinolate (source of goitrogenic thiocyanate ion) content had been reduced, but not S-methylcysteine sulphoxide (the haemolytic factor) content. Selection differentials each generation were small and heritabilities of family means were moderate to low, making improvement per generation slow. It was demonstrated that faster progress could be made by switching from half-sib to full-sib family selection, as expected from theory. Multiplication of the half-sib family with the highest digestibility (DOMD%) achieved an improvement in this trait, without a reduction in digestible organic matter yield, and was marketed as cultivar Grampian.     

Introgression of clubroot resistance into an elite pak choi inbred line through marker‐assisted introgression breeding

Clubroot is a soilborne disease that severely infects cruciferous species. Pak choi (Brassica rapa subsp. chinensis) is an economically important cruciferous crop cultivated throughout the world. However, no clubroot‐resistant germplasms have been identified in pak choi to date. To improve disease resistance, we used marker‐assisted selection (MAS) to introgress the clubroot resistance (CR) trait from the ‘CCR13685’ Chinese cabbage (B. rapa subsp. pekinensis) inbred line into an elite pak choi inbred line, ‘GHQ11021’. Genetic analysis of F₂ and BC₁ progeny showed that CR of ‘CCR13685’ was controlled by a single dominant gene. We designed nine candidate sequence‐characterized amplified region markers, K‐1 to K‐9, based on two molecular markers linked to the CR gene. We found that K‐3 co‐segregated with CR and an inoculation test confirmed that K‐3 could be used for MAS. Two introgression lines, BC₃‐1‐4 and BC₃‐2‐18, were developed using K‐3 for foreground selection. These lines displayed the same phenotypic properties as ‘GHQ11021’, but were highly resistant to clubroot, indicating that the CR gene of ‘CCR13685’ had been successfully introduced into pak choi.     

Genetic potential of a maize population from Southern Brazil for the modified convergent–divergent selection scheme

Maize (Zea mays L.) is a very important cereal to world-wide economy which is also true for Brazil, particularly in the South region. Grain yield and plant height have been chosen as important criteria by breeders and farmers from Santa Catarina State (SC), Brazil. The objective of this work was to estimate genetic-statistic parameters associated with genetic gain for grain yield and plant height, in the first cycle of convergent–divergent half-sib selection in a maize population (MPA1) cultivated by farmers within the municipality of Anchieta (SC). Three experiments were carried out in different small farms at Anchieta using low external agronomic inputs; each experiment represented independent samples of half-sib families, which were evaluated in randomized complete blocks with three replications per location. Significant differences among half-sib families were observed for both variables in all experiments. The expected responses to truncated selection of the 25% better families in each experiment were 5.1, 5.8 and 5.2% for reducing plant height and 3.9, 5.7 and 5.0% for increasing grain yield, respectively. The magnitudes of genetic-statistic parameters estimated evidenced that the composite population MPA1 exhibits enough genetic variability to be used in cyclical process of recurrent selection. There were evidences that the genetic structure of the base population MPA1, as indicated by its genetic variability, may lead to expressive changes in the traits under selection, even under low selection pressure.     

Molecular marker-assisted selection for development of common bean lines resistant to angular leaf spot

The objective of this work was to develop homozygous common bean lines carrying angular leaf spot resistance genes derived from the cultivars ‘Mexico 54’, ‘MAR 2’ and ‘BAT 332’ through marker‐assisted selection. Molecular markers SCAR OPN02₈₉₀, RAPD OPE04₅₀₀ and OPAO12₉₅₀ linked to the resistance genes of ‘Mexico 54’, ‘MAR 2’ and ‘BAT 332’, respectively, were used in segregating backcross‐derived populations to selection. DNA fingerprinting was used to select homozygous BC₂F₃ and BC₁F₃ resistant plants genetically closer to the recurrent parent. Two homozygous BC₂F_2:3 and two and five BC₁F_2:3 families derived from ‘Ruda’ vs. ‘Mexico 54’ (RM), ‘MAR 2’ (RMA) and ‘BAT 332’ (RB) crosses were selected, respectively. After only one (RMA, RB) or two backcrosses (RM), five and eight BC₁F₃ lines derived from RMA and RB, respectively, and seven BC₂F₃ lines derived from RM, with 14.9–16.6, 16.9–18.6 and 9.3–11.1% of relative genetic distances to the recurrent parent were selected. This is the first report of lines resistant to angular leaf spot carrying genes of the cultivars ‘Mexico 54’, ‘MAR 2’ and ‘BAT 332’ developed with the aid of molecular markers.