Morpho-Physiological and Genetic Responses of Bali Local Rice Cultivars to Drought Stress at Seedling Stage
Made Pharmawati and Luh Putu Wrasiati
DOI : 10.3844/ojbsci.2018.101.107
OnLine Journal of Biological Sciences
Volume 18, Issue 1
Rice is the main food source in many countries in the world. One of the major limiting factors for rice growth and productivity is drought stress. In Bali there are several local rice cultivars, two of them are ‘Mansur' and ‘Putih Cempaka'. The cultivar ‘IR 64' is one rice cultivar released by IRRI. The responses of those rice cultivars to drought stress were tested. This study aimed to analyze growth responses and expression of DREB and SOD genes under drought stress induced by PEG. Rice seedlings were grown in a hydroponic system. Two weeks old seedlings were treated with PEG 20% (-0.49 MPa) and 30% (-1.03 MPa) for three days. Root to shoot ratio was calculated and chlorophyll content was measured. RNA was extracted from the shoot. Semi-quantitative real-time PCR was conducted and the products were visualized using 1% agarose gel electrophoresis. The result showed that root to shoot ratio increased as PEG concentration increased in all rice cultivars tested. The chlorophyll content decrease under PEG treatments in all rice cultivars. The expression of Superoxide Dismutase (Cu/Zn-SOD) gene increased under drought treatmentsin ‘Mansur’ and ‘Putih Cempaka’, while in ‘IR64’ using SOD primer tested, the gene was not expressed. The expression of Dehydration-Responsive Element Binding (DREB1) gene increased under PEG treatments both in ‘Mansur’ and ‘Putih Cempaka’.
© 2018 Made Pharmawati and Luh Putu Wrasiati. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.