Irrigated lowland rice is the most important rice ecosystem in Malaysia. The present and future food security in rice for the country depends largely on the irrigated lowland rice production system which consumes a large amount of water. Signs of declining water availability due to increased demand of water for domestic and industrial uses besides irregularity of rainfall and climate change threatens the sustainability of irrigated rice production. This scenario may change the way rice is produced in the future. Aerobic rice is a potential water saving rice production system and will be the best option of producing rice in water scarce environment. The availability of aerobic rice varieties that can withstand aerobic condition, responds to irrigation and fertilizers, competitive against weeds and deliver a high yield is crucial to make aerobic rice cultivation successful. Since weeds are major constraints to aerobic rice, it must be effectively controlled through integrated weed management. Appropriate nutrient and other crop management practices will ensure successful aerobic rice production system.

The research was conducted at MARDI Seberang Perai research plot during main-season 2011/2012 and off-season 2012. Varieties such as MR 272, MR 278, MR 283 and MR 284 showed high yield potential as compared to the control varieties namely MR 211, MR 219, MR 253 and MR 263. According to correlation analysis, traits such as flag leaf width (r = 0.36, p = 0.01), percentage filled grain (r = 0.43, p = 0.002) and spikelets number/panicle (r = -0.43, p = 0.002) showed association toward yield potential. As a result, high rate of photosynthesis is depend to high leaf surface area. In addition, low number of spikelets /panicle can enhance the grain filling.