Two-Step Salt Stress Acclimatization Confers Marked Salt Tolerance Improvement in Four Rice Genotypes Differing in Salt Tolerance

Autor: Sumontip Bunnag, Anawat Suwanagul, Warisa Pilahome
Rok vydání: 2016
Předmět:
Zdroj: Arabian Journal for Science and Engineering. 42:2191-2200
ISSN: 2191-4281
2193-567X
Popis: In this study, four rice genotypes were evaluated for their salt tolerance characteristics in terms of ion concentrations and expression levels of OsHAK1, a gene that is involved in the regulation of K ion uptake. Salt tolerance profiles were assessed at 0, 0.5, 1.0, 1.5 and 2.0% NaCl. It was observed that the growth of salt-sensitive (RD6 and Sakon Nakhon) and moderately salt-tolerant (Niaw Ubon 2) cultivars were completely inhibited at 1.5% NaCl, with satisfactory growth observed for salt-tolerant (Pokkali) cultivar. One- and two-step treatments were compared for their efficacy in inducing salt tolerance in rice plants. One-step treatment was ineffective for producing rice plants with improved salt tolerance, while two-step treatment was a promising approach, producing salt-tolerant rice plants growing vigorously at 1.5% NaCl. Inductively coupled plasma–optical emission spectrometry indicated that salt-sensitive cultivars produced from two-step treatment showed improvements in their abilities to maintain \(\hbox {Na}^{+}/\hbox {K}^{+}\) ratios. Real-time qRT-PCR revealed that a remarkable increase in the OsHAK1 transcript level was not observed in plants grown at 1.5% NaCl. Besides, the OsHAK1 transcript level was not related to Na and/or K concentrations, and \(\hbox {Na}^{+}/\hbox {K}^{+}\) ratios, suggesting that other genes involved in \(\hbox {K}^{+}\) uptake regulation may express at higher levels and therefore, OsHAK1 expressed at low levels.
Databáze: OpenAIRE
Externí odkaz: