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Faba bean (Vicia faba L.) is a globally important nitrogen-fixing legume, which is widely grown in a diverse range of environments. In this work, we mine and validate a set of 845 SNPs from the aligned transcriptomes of two contrasting inbred lines. Each V. faba SNP is assigned by BLAST analysis to a single Medicago orthologue. This set of syntenically anchored polymorphisms were then validated as individual KASP assays, classified according to their informativeness and performance on a panel of 37 inbred lines, and the best performing 757 markers used to genotype six mapping populations. The six resulting linkage maps were merged into a single consensus map on which 687 SNPs were placed on six linkage groups, each presumed to correspond to one of the six V. faba chromosomes. This sequence-based consensus map was used to explore synteny with the most closely related crop species, lentil and the most closely related fully sequenced genome, Medicago. Large tracts of uninterrupted colinearity were found between faba bean and Medicago, making it relatively straightforward to predict gene content and order in mapped genetic interval. As a demonstration of this, we mapped a flower colour gene to a 2-cM interval of Vf chromosome 2 which was highly colinear with Mt3. The obvious candidate gene from 78 gene models in the collinear Medicago chromosome segment was the previously characterized MtWD40-1 gene controlling anthocyanin production in Medicago and resequencing of the Vf orthologue showed a putative causative deletion of the entire 5′ end of the gene.

Drought stress is a major abiotic stress factor, constraining wheat production and quality worldwide. Several drought indices were used to identify drought-tolerant lines among 49 wheat lines. These lines were grown in three locations in Egypt, under rainfed (Barrani and Matrouh) and irrigated (Assiut) conditions. Results showed that grain yield under stress and non-stress environments were highly correlated with the mean productivity (MP), the geometric mean productivity (GMP), stress tolerance index (STI), yield index (YI), harmonic mean (HM), drought resistance index (DRI), and modified stress tolerance index (STI). We found that MP, GMP and STI were considered the best indices for the selection of the relatively tolerant lines. Principal component analysis indicated that the first two components accounted for more than 98% of the total variations for drought tolerant indices.

Bolting tendency in sugar beet is a complex trait has been shown to be controlled by various environmental cues, including prolonged periods of cold temperatures over winter (vernalization) and photoperiod, and multiple genetic factors. Three loci (B, B2 and B4) which trigger bolting in the absence of vernalization were identified and genetically mapped in beet. B4 is linked to the B locus and promotes annual bolting independently of B. Here, genetic analysis of a large segregated F2 population derived from a cross between a biennial sugar beet and an annual beet accession phenotyped for bolting tendency under three environmental conditions, i.e., long day after vernalization, long day without vernalization and shortening daylength revealed the presence of a major gene which is linked to the gene B and suppresses bolting under unfavorable daylength (shortening daylength) and negatively affects bolting time.

—Beta vulgaris ssp. maritima is a facultative perennial species exhibits large intraspecific variation in vernalization requirement. Bolting tendency is a complex character governed by various environmental cues and multiple genetic factors. A panel of B. vulgaris ssp. maritima accessions collected from the Mediterranean costs revealed significant variations in bolting time. Three F2 populations derived from crosses between six annual beet accessions were analyzed for bolting behavior. Two F2 segregated populations, i.e., Bvm127 and Bvm128 exhibited phenotypic segregation ratios of 3 : 1 earlybolting and latebolting which is expected for dominantrecessive inheritance of a monogenic trait. Meanwhile, the phenotypic segregation ratio for early bolting: latebolting in the F2 population Bvm125 did not deviate significantly from 63 : 1, indicating a poly genic inheritance of bolting tendency in Beta vulgaris ssp. maritime. Broad sense heritability for bolting ten dency ranged from 0.58 to 0.74.

Migratory plant parasitic nematodes from the genus Pratylenchus are major pests in agriculture and attack a wide spectrum of crops leading to heavy losses up to 16% of grain yield in barley. Breeding resistant varieties is the most effective and environmentally friendly approach to control root lesion nematodes. A doubled haploid population derived from a cross between the Turkish accession Beysehir and the old German variety Valentina were used for genetic mapping of P. neglectus resistance QTLs. A genetic linkage map was constructed using 226 DH lines with 388 AFLP, SSR and CAPS markers that cover 1,051 cM on seven linkage groups. Using nematode numbers which were counted 7 weeks after artificial infection, eight QTLs were mapped by composite interval mapping on six linkage groups (2H, 3H, 4H, 5H, 6H and 7H). Comparative QTL analysis revealed that two major QTLs are located at the same position as previously described Pratylenchus resistance QTLs on chromosomes 5 and 6 (Rlnnp5H and Rlnnp6H) which had been mapped with two different. Two markers flanking Rlnnp6H are being used to identify DH lines with recombinations within the QTL regions in a large DH population of Beysehir × Valentina. Currently, 760 DH lines have been genotyped with the two flanking markers and 35 recombinant DHs were identified. Recombinant DH lines will be used for fine mapping of the QTL taking the markers selected by whole genome sequencing of two phenotypic bulks. Two phenotypic bulks representing the distributional extremes of the mapping population were subjected to whole genome sequencing using Illumina HiSeq 2000 technology. Short reads from the susceptible bulk were aligned to the barley reference genome sequence, and a consensus reference sequence was obtained. Reads from the resistant bulk were mapped to the consensus reference sequence and variants between the two bulks were identified. Homozygous variants densities were calculated across all chromosomes in a sliding window of 1Mb using CLC Genomics Workbench 6.5. Preliminary results show that a unique region with the highest variant density was localized at the same position as one of the resistance QTL. Sequence analysis to identify resistance candidates is in progress.

Heat stress is an important abiotic stress causing the major threat to the growth and development of most crop plants. A panel of 326 barley genotypes comprises of 320 wild barley accessions and six local cultivars were evaluated for days to heading (DTH), days to flowering (DTF), number of tillers per plant (NoT), plant height (PH), Chlorophyll content (CC), spike length (SL), thousand kernel weight (TKW) and single plant yield (SPY) under optimum sowing and heat-stressed conditions. All measured traits exhibited highly significant differences both among evaluated genotypes and between the optimum sowing and the heat-stressed conditions. Plants exposed to high temperatures flowered earlier. A drastic reduction in morphological and yield contributing traits, i.e., PH, NoT, SL, TKW, SPY and CC under heat stress conditions was observed. Cluster analysis revealed two distinct groups based on heat stress tolerance with substantial diversity among the heat tolerant genotypes.

Heat stress is an important abiotic stress causing the major threat to the growth and development of most crop plants. A panel of 326 barley genotypes comprises of 320 wild barley accessions and six local cultivars were evaluated for days to heading (DTH), days to flowering (DTF), number of tillers per plant (NoT), plant height (PH), Chlorophyll content (CC), spike length (SL), thousand kernel weight (TKW) and single plant yield (SPY) under optimum sowing and heat-stressed conditions. All measured traits exhibited highly significant differences both among evaluated genotypes and between the optimum sowing and the heat-stressed conditions. Plants exposed to high temperatures flowered earlier. A drastic reduction in morphological and yield contributing traits, i.e., PH, NoT, SL, TKW, SPY and CC under heat stress conditions was observed. Cluster analysis revealed two distinct groups based on heat stress tolerance with substantial diversity among the heat tolerant genotypes.