Genetic variance of malate transporter gene in barley (Hordeum vulgare L.)

HvALMT1 encodes a malate transporter responsible for malic acid efflux in barley on 2H. The gene was characterized to contribute to anion homeostasis and stomatal adjustment. However, it has been debated for some time whether the gene function is related to Al tolerance. We developed thirty-six pairs of primers covering whole gene sequence and tested polymorphisms in 335 accessions with different Al tolerance. Phenotypic variation was evaluated in native acid soil and limed acid soil. Ten pairs of primers (4 in the upstream region, 6 in the coding region,) showed polymorphisms. Stepwise regression analysis revealed one gene-specific marker, UA21, was significantly correlated with phenotypic variation of root length in acid soil (r = 0.301, p < 0.01) and relative root length (root length in acid soil compared with that in acid soil treated with lime) (r = 0.246, p < 0.01). The results demonstrated that malate transporter gene may play a role for acids soil tolerance in some of the germplasm.