Overexpression of TaBADH increases salt tolerance in Arabidopsis

Soil salinization is an important threat to wheat growth and production. Previous transcriptome analysis showed that the expression of the betaine aldehyde dehydrogenase (BADH) gene differed significantly between cultivars with strong or weak salinity tolerance. Herein, the BADH gene from the wheat cultivar Dongnongdongmai 1 was cloned and transformed into wild-type Arabidopsis to identify its function in salt tolerance. Root length was calculated at 0, 50, 100, 150, and 200 mmol L−1 NaCl for 7 d. The relative electrolytic leakage (REL), GB content, and BADH activity were measured at 150 mmol L−1 NaCl for 1 and 3 d. It was determined that BADH activity and the GB content of TaBADH-overexpressed transgenic (TaBADHOE) lines were significantly higher than in wild-type lines. Salt stress analysis showed that the root length of TaBADHOE lines 4, 18, and 19 were 0.44, 0.54, and 0.35 cm, respectively, which were significantly longer than the 0.24 cm roots of the wild-type line in the media containing 150 mmol L−1 NaCl for 7 d. In addition, the RELs of transgenic lines 4, 18, and 19 were 0.37, 0.33, and 0.42, respectively, which is significantly lower than the 0.63 of the wild-type line in media containing 150 mmol L−1 NaCl for 3 d. These results demonstrate that TaBADH significantly increased plant salt tolerance, indicating that genetic transformation of TaBADH may be an effective and sustainable breeding method for increasing salt tolerance in wheat cultivars.

Betaine Aldehyde Dehydrogenase (BADH) gene and free amino acid analysis in Rhizophora mucronata Lam. from Thalassery region of Kerala, India.

Mangroves are salt tolerant plants inhabiting saline environment. Multiple factors contribute to their salt tolerance and we need multifaceted approach to reveal the mechanisms of salt tolerance in the plant. In the present study, leaves of the mangrove, Rhizophora mucronata grown in the presence and absence of salt were used, free amino acids and the expression of selected genes were analyzed. Chromatographic technique showed the accumulation of free amino acids like proline, glycine, aspartic acid, valine, leucine and glutamic acid in the presence of salt. RNA was isolated from the leaf sample and cDNA was synthesized. Gene specific primers were designed and standardized. Among the genes studied (P5CS, BADH, NHX1), Betaine Aldehyde dehydrogenase (BADH) gene was found to be expressed.