Analysis of transcription factors expression patterns; ZFP252, MYB3R-2 and AP37 and root length in rice under drought stress

Rice is one of the most important crops in Asian countries, because of limitation in water resources, the studies on plant tolerance mechanisms to drought stress and the use of tolerant genotypes are going to be more considered. In current research, three Iranian rice cultivars named Neda, Amol3, and Sang-tarom with different responses to drought stress were used. The rice seedlings were grown in three treatments including control (Fraction of Transpirable Soil Water=1.0), mild drought stress (FTSW=0.5) and severe drought stress (FTSW=0.2) in glasshouse. The root length and the expression levels of three transcription factors, ZFP252, MYB3R-2 and AP37were investigated in vegetative stage of growth by qRT-PCR. Neda showed significant increase (P<0.05) in root length with compared to Sang-tarom in mild and severe drought stress but there were not any significant differences between Neda and Amol3. Neda had less significant increases (P<0.05) in expression levels of ZFP252, MYB3R-2 and AP37with compared to Sang-tarom in mild drought stress and also less significant increases in expression levels of ZFP252 and AP37 with compared to Amol3.In severe drought stress (FTSW=0.2), Neda showed less significant expression levels of all three transcription factors with compared to Sang-tarom. Neda is probably more tolerant line and also a candidate for selection against drought stress due to longer roots but there are different mechanisms in responses to drought stress in genes expression levels in different rice lines.