In barley, three genes are responsible for the vernalization requirement: VrnH1, VrnH2 and VrnH3. The winter growth habit of barley requires the presence of a recessive VrnH1 allele, together with an active VrnH2 allele. The candidate for VrnH3 (HvFT1) has been recently identified, with evidences pointing at a central role in the integration of the vernalization and photoperiod pathways. Functional polymorphisms have been proposed, but experimental evidence of their role on agronomic performance and adaptation is needed. We examined allelic variation at the promoter and intron 1 of the HvFT1 gene in a landrace collection of barley, finding a high diversity level, with its geographic distribution correlated with latitude. Focusing on genotypes with winter alleles in VrnH1 and VrnH2, an association analysis of the four main HvFT1 haplotypes found in the landrace collection detected differences in time to flowering. Landraces with the intron 1 TC allele, prevalent in the south, flowered 6-7 days earlier than those with the AG allele, under natural conditions. These results were validated in an independent F(2) population. In both data sets, the effect found was similar, but in opposite direction to that described in literature. The polymorphism reported at intron 1 contributes to variation in flowering time under field conditions. We have found that polymorphisms at the promoter also contribute to the effect of the gene on flowering time under field and controlled conditions. The variety of HvFT1 alleles described constitutes an allelic series that may have been a factor in agro-ecological adaptation of barley.

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Saharan maize had been adapted to extreme conditions and could have developed resistance to different stresses. However, genebanks and breeding collections have poor representation from Saharan germplasm and, particularly, from Algeria. This is a preliminary approach to investigate the adaptation and agronomic performance of a representative sample of Saharan maize. We evaluated open-pollinated Saharan populations along with European and American cultivars during two years in humid and dry Spanish locations and in Algiers (Algeria). Saharan populations were able to grow in temperate environments, although results were not consistent over years and the genotype-by-environment interactions were very important. Some of the Algerian populations evaluated in 2010 showed promising yield and anthesissilking interval over environments, but none of the Algerian populations evaluated in 2009 were adequately adapted to Spanish conditions. These results suggest that there are wide ranges of variability within Saharan maize for adaptation to temperate conditions, and further evaluations of Saharan maize should identify potential base populations for breeding maize in either side of the Mediterranean Sea. However, this germplasm requires prebreeding for adaptation to temperate conditions in order to be adequate for breeding programs in temperate areas.