To develop a high density linkage map in faba bean, a total of 1,363 FBES (Faba bean expressed sequence tag [EST]-derived simple sequence repeat [SSR]) markers were designed based on 5,090 non-redundant ESTs developed in this study. A total of 109 plants of a ‘Nubaria 2’ × ‘Misr 3’ F2 mapping population were used for map construction. Because the parents were not pure homozygous lines, the 109 F2 plants were divided into three subpopulations according to the original F1 plants. Linkage groups (LGs) generated in each subpopulation were integrated by commonly mapped markers. The integrated ‘Nubaria 2’ × ‘Misr 3’ map consisted of six LGs, representing a total length of 684.7 cM, with 552 loci. Of the mapped loci, 47% were generated from multi-loci diagnostic (MLD) markers. Alignment of homologous sequence pairs along each linkage group revealed obvious syntenic relationships between LGs in faba bean and the genomes of two model legumes, Lotus japonicus and Medicago truncatula. In a polymorphic analysis with ten Egyptian faba bean varieties, 78.9% (384/487) of the FBES markers showed polymorphisms. Along with the EST-SSR markers, the dense map developed in this study is expected to accelerate marker assisted breeding in faba bean.

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Production of grain legumes is limiting by the usual array of pathogenic that affect plants. The present study was conducted during 2005/06, 2006/07 and 2007/08 seasons at Sakha Agricultural Research Station (SARS). A quantitative analysis were done by using six generations mating design between five faba bean parental genotypes namely; Rena Mora, Sakha1, Giza 3, Sakha 2 and T.W to produces three crosses namely; Rena Mora x Sakha1, Giza 3 x Rena Mora and Sakha 2 x T.W. The parental genotypes could be arranged in to three groups. The first group included; Rena Mora, Sakha 1 and Sakha 2 where it is considered as the most resistant group to chocolate spot and high yielding ability. The second group included Giza 3 which is moderate resistant to chocolate spot and the third group include T.W as susceptible genotypes with low yielding potentiality. The data revealed that, the parental genotypes and their crosses had the highest value of variation according to relation to chocolate spot reaction and maturity date. Heterosis over mid and better parent for all traits were highly significant except chocolate spot reaction in the two crosses; (Rena Mora x Sakha1) and (Sakha 2 x T.W.) relative to mid parents. And also, for no. of pods/plant in the cross; (Rena Mora x Sakha1) relative to better parent. Potence ratios were exceeded unity for most traits indicating over dominance. On the other hand, the values of this parameter were less than unity in the cross; (Sakha 2 x T.W.) for maturity date, no. of branches/plant, seed yield/plant(g), 100 seed weight and chocolate spot reaction, indicating partial dominance. The inbreeding depression estimates were highly positively significant for no. of pods/plant, no. of seeds/plant and seed yield/ plant(g) in the two crosses (Rena Mora x Sakha1) and (Giza 3 x Rena Mora). The additive type (a) was significant positive or negative values in all of crosses for all traits except in the cross; (Rena Mora x Sakha 1). For dominance effect (d) it was and higher in magnitude than that of additive type of gene effects. The additive x additive gene effect was highly positive significant in most crosses except in the cross; (Rena Mora x Sakha 1) for no. of branches/plant. However, highly significant positive epistatic gene action (ad) was observed in the first cross; (Rena Mora x Sakha 1) for no. of branches/plant, no. of pods/plant, no. of seeds/plant and chocolate spot reaction. Heritability values in broad-sense were generally higher than the corresponding values in narrow-sense in all crosses for all traits. The additive genes seems to play an important role of the inheritance of maturity date, no. of branches/plant, no. of pods/plant and chocolate spot reaction in the cross; Rena Mora x Sakha1, where the differences between broad and narrow-sense heritability were closest. The indirect selection in the progeny of the crosses; Rena Mora x Sakha 1 and Giza 3 x Rena Mora and direct selection in the progeny of the cross (Sakha 2 x T.W.) would be fruitful due to the high values of narrow-sense h...

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