DArT is a hybridization-based molecular marker system. It has been used in barley [90], wheat [91], rye [92] and triticale [93].

It is particularly noted for its high-throughput, quickness, high reproducibility and low cost [94]. Hundreds to thousands of polymorphisms can be detected Selleckchem SGI-1776 very quickly [95]. The use of DArT markers to perform whole-genome mapping in some Brazilian wheat cultivars validated the citrate efflux mechanism for Al tolerance [59]. DArT markers combined with SSR and STS markers also validated the candidate Al tolerance gene HvMATE on chromosome 4H in barley [89]. Genetic mapping refers to the mapping of gene/loci to specific chromosome locations using linked genetic markers [96]. Some cereal crops, such as wheat [97], barley, sorghum (Sorghum bicolor L.) and oat were reported to have simple genetic mechanisms of Al tolerance, whereas rice and maize (Zea mays L.) have more complicated inheritance with numerous genes/loci involved. Generally, a single dominant gene is responsible for Al tolerance in wheat [98]; however,

there are exceptions in some cultivars [99]. Using different populations, genes/loci for Al tolerance were mapped on different wheat chromosomes. Single loci for Al tolerance Y-27632 price were identified on chromosomes 4DL, 4D, 4BL or 3BL, which had phenotypic contributions as high as 85% (locus on 4DL), 50% (4D), 50% (4BL) and 49% (3BL) [59], [81], [86] and [100]. In addition, genes/loci on chromosomes 6AL, 7AS, 2DL, 5AS, 3DL Resveratrol and 7D had roles in Al tolerance in wheat [101] and [102]. Complex inheritance of Al tolerance was found in wheat. Zhou et al. [103] identified a secondary QTL for Al resistance on chromosome 3BL in Atlas 66, which was effective only when the epistatic gene on 4DL was absent. Cai et al. [104] mapped three QTL responsible for Al tolerance on wheat chromosomes 4DL, 3BL and 2A, which collectively explained 80% of the phenotypic variation. In sorghum, Al tolerance was simply inherited [105]. Magalhaes et al. [106] reported a major locus AltSB

on chromosome 3 for Al tolerance using comparative mapping. In rye, Al tolerance was reported to be controlled by several loci; at least four independent loci, Alt1 on 6RS [107], Alt2 on 3RS [101], Alt3 on 4RL [83] and Alt4 on 7RS [108], were validated by QTL analysis. The genes on 3R, 6RS and 4R were validated using wheat addition and substitution lines with rye chromosomes [101]. Gallego and Benito [109] reported that Al tolerance in rye was controlled by dominant loci Alt1 and Alt3; the latter on chromosome 4RL was validated using recombinant inbred lines [83]. Alt4 on chromosome 7RS was identified in three different F2 populations [108]. In Arabidopsis, Al tolerance seems to be multi-genetically controlled.