Towards Developing Salinity Tolerant Rice Adaptable for Coastal Regions in Indonesia
Lowland rice areas along the coastal regions are a major contributor for rice production in Indonesia. Sustainability of rice production in those areas is challenged by the increase of soil salinity as the result of sea water inundation. The problem is exacerbated by the increase of sea water level as the impact of global climate change. High concentration of salt ion in the soil could significantly reduce rice growth and yield. Development of salinity tolerant rice varieties is therefore important to maintain sustainability of rice production in the coastal regions. Breeding programs to improve salinity tolerance of Indonesian rice has been established in Indonesian Centre for Rice Research. Through intensive salt tolerant screening program genetic variations in salinity tolerance have been identified within rice germplasm allowing the improvement of salinity tolerant of existing rice varieties. Different genetic resources have been used for salinity tolerant improvement including landraces, improved varieties and introduction lines. A number of promising salt tolerant rice breeding lines have been developed and showed adaptability to salt affected areas in the lowland coastal areas. Two new salt tolerant rice varieties have been released recently which are adaptable to salt affected areas. This paper will describe the progress in the breeding programs to develop salt tolerant rice for lowland rice areas in the coastal regions. Strategy to accelerate the improvement of the salinity tolerant of Indonesian rice varieties in the future will be also discussed.Keywords:
rice, breeding, salinity tolerance, coastal regions.
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