Abstract

Aluminium (Al) toxicity stress reduces crop yields in acidic soils. In this study, we investigated the level of DNA Cytosine methylation polymorphism caused by 150 μM Al³⁺ (89.97% free Al³⁺) induction, low pH (4.0) and continuous application of 150 μM Al³⁺ in Sorghum inbred lines using methylation sensitive amplified polymorphism analysis (MSAP) and searched for homologies using the BLASTN program. We found that 150 μM Al³⁺ toxicity and low pH induced a persistent moderate DNA cytosine (C) methylation changes at early seedling stage. Analysis of DNA CG and CNG methylation levels showed variations amongst the inbreeds with more changes occurring at the CNG level than in the CG level. Morphological observations showed that Al and low pH stress triggered crop yield changes. BLAST analysis suggested that possible polymorphisms occurred in the regulatory regions of Al tolerance genes mainly via histone deacetylase, methyltransferase, peptide signals and transcription factors and could have definite roles in allelic effects which influence gene expression and an increase in Sorghum stress resistance.

Key words: Aluminium toxicity, DNA methylation, epigenetics, methylation sensitive amplified polymorphism analysis (MSAP), sorghum.