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Multi-interval mapping of correlated trait complexes is discussed using the North American Barley Genome Mapping Project as an example. Information about using Monte Carlo simulations and demonstrating thereby advantages of multitrait analysis in detection of linked quantitative trait loci (QTL) effects in the framework of mixture models is given. Despite more parameters estimated vs single-trait formulation, the method proposed allows for detection power improvement and estimation precision of linked QTLs in adjacent or nonadjacent intervals, coupling and repulsion effects included.

A complex adaptive syndrome in Drosophila melanogaster caused by mircroclimatic contrasts is discussed. The multiple adaptive differences are between isofemale lines derived from opposite slopes of a canyon in Israel. Strong microclimatic natural selection in this site with stressful environmental conditions appears to override migration in Drosophila at the microsite. The interslope differentiation could be ideally illustrative for learning about grnetic bases of environmental tolerance.

A study examines whether the physiological evolution of two Drosophila melanogaster populations on opposite slopes of Lower Nahal Oren, Mt. Carmel, Israel, despite a spatial separation of only 100-400 meters, was idiosyncratic and temporary, or persisted over multiple years. Results show that interpopulation differences in thermotolerance were stable despite year-to-year and seasonal variation in environmental conditions and potential inter-slope migration.

Research has been conducted on natural population of wild emmer wheat Triticum dicoccoides. The role of the allele size constraints and genetic and clustering effects in simple sequence repeat diversity in this population has been investigated, and the details are reported.

The effects of microclimatic stresses on adaptive dinucleotide microsatellite (SSR) divergence in natural subpopulations of wild emmer wheat at a microscale, are presented. The evidence reflects the effects of ecological stresses, and natural selection on SSR diversity that results in presumable adaptive structures.

Flowering time is one of the most critical traits for plants' life cycles, which is influenced by various environment changes, such as global warming. Previous studies have suggested that to guarantee reproductive success, plants have shifted flowering times to adapt to global warming. Although many studies focused on the molecular mechanisms of early flowering, little was supported by the repeated sampling at different time points through the changing climate. To fully dissect the temporal and spatial evolutionary genetics of flowering time, we investigated nucleotide variation in ten flowering time candidate genes and nine reference genes for the same ten wild-barley populations sampled 28 years apart (1980-2008). The overall genetic differentiation was significantly greater in the descendant populations (2008) compared with the ancestral populations (1980); however, local adaptation tests failed to detect any single-nucleotide polymorphism (SNP)/indel under spatial-diversifying selection at either time point. By contrast, the WFABC (Wright-Fisher ABC-based approach) that detected 54 SNPs/indels was under strong selection during the past 28 generations. Moreover, all these 54 alleles were segregated in the ancestral populations, but fixed in the descendent populations. Among the top ten SNPs/indels, seven were located in genes of FT1 (FLOWERING TIME LOCUS T 1), CO1 (CONSTANS-LIKE PROTEIN 1), and VRN-H2 (VERNALIZATION-H2), which have been documented to be associated with flowering time regulation in barley cultivars. This study might suggest that all ten populations have undergone parallel evolution over the past few decades in response to global warming, and even an overwhelming local adaptation and ecological differentiation.

Simultaneous genomic in situ hybridization (GISH) with probe preannealing was used to detect the relationship between chromosomal position and sequence conservation on Aegilops speltoides var. aucheri chromosomes. DNA of Secale sylvestre, Hordeum spontaneum, Festuca pratensis, Semiarundinaria fastuosa, Arundo donax and Zea mays that represent several main groups of Poaceae were used as probes. Different GISH-banding patterns that characterize diverse evolutionary trajectories in the repetitive DNA fraction and correlate with evolutionary distance between tested species were observed. Fast-evolving sequences were detected in subterminal telomeric and subtelomeric heterochromatic regions, whereas sequences in pericentromeric regions showed high levels of conservation. GISH experiments revealed extensive conservation in NOR regions on chromosomes 1 and 6 which, in fact, appears to be a complicated mix of rDNA clusters and heterochromatin blocks of different nucleotide composition.

Allozyme diversity in the superspecies Spalax ehrenbergi has been revisited by studying 36 gene loci in 241 subterranean mole rats from 22 populations and nine chromosomal species, four from Turkey (2n = 52E (east), 52W (west), 56 and 58), four from Israel (2n = 52, 54, 58 and 60), and one from Egypt (2n = 60). The following results were indicated. (1) Genetic patterns: 11 of the 36 loci analysed (30.5 per cent) were monomorphic across the range, fifteen (41.7 per cent) were weakly polymorphic and the remaining 10 loci (27.8 per cent) were strongly polymorphic. (2) Heterozygosity: the average H was 0.051, range 0.00-0.098. In Israel, H increased with aridity and climatic unpredictability towards the northern Negev Desert, and was remarkably high in small steppic semi-isolates and desert isolates. (3) Species discrimination: some of the S. ehrenbergi species can be discriminated qualitatively. (4) Genetic distances (D): between species these values averaged 0.077, range 0.001-0.269, with the highest D between the ancestor Turkish and descendant Israeli and Egyptian species. The phylogenetic tree supports the Turkish origin of the Israeli Spalax ehrenbergi species, and the recent speciation of the Egyptian Spalax. (5) Genetic diversity is mostly (58 per cent) within populations. (6) Allozyme correlates: allozyme diversity was significantly correlated with the external physical (both climatic and edaphic) and biotic (parasite infection and plant cover) environment. (7) Spatial autocorrelation of allozyme frequencies suggests that migration is not influential. (8) Gametic phase disequilibria were significant in four out of five species tested, and were associated with climatic and edaphic factors. These results support the environmental selection hypothesis of genetic diversity including the niche-width variation hypothesis in space and time. Natural selection appears to play a major role in genetic differentiation of proteins in adaptive radiation and speciation.

We analysed the genetic diversity and environmental correlates of the aldolase A and B genes by means of restriction endonucleases (DNA RFLP analysis), in the four chromosomal species (2n = 52, 54, 58 and 60) of the actively speciating subterranean mole-rats of the Spalax ehrenbergi superspecies in Israel. The results indicated that: (i) both aldolase genes are highly polymorphic; (ii) fragment frequencies and fragment profiles display geographical patterns and significant ecological correlates; (iii) discriminant analysis largely succeeded in separating the four chromosomal species on the basis of variation of aldolase RFLPs.

We analyzed the genetic diversity and environmental correlates of the haptoglobin (Hp) gene by RFLP analysis of 121 subterranean mole rats, comprising 13 populations belonging to the 4 chromosomal species (2n = 52, 54, 58 and 60) of the actively speciating Spalax ehrenbergi superspecies in Israel. The following results were indicated: (i) Out of the six restriction enzymes we tested, we found polymorphism only in TaqI, with three allelic fragments, and described their geographic patterning. (ii) Genetic diversity of Hp was highest in the centre of the range. (iii) The two major alleles showed high significant and opposite correlation with humidity. (iv) Genetic differentiation analysis indicated that 40 per cent of the Hp variation was within, and 60 per cent between populations. We conclude that climatic selection plays an important role in haptoglobin genetic differentiation.