Compositional analysis of protoporphyrinogen oxidase-inhibiting herbicide-tolerant rice and conventional rice

Abstract

Protoporphyrinogen oxidase (PPO) is a key enzyme of peroxidising herbicides. Transgenic rice event CPPO06, which overexpresses PPO gene derived from soil bacterium, Myxococcus xanthus, showed high resistance to PPO inhibitors. This study was designed to compare the compositional profile of rice event CPPO06 with that of conventional control and commercial cultivars. Field trials were carried out in the three different regions of South Korea during the 2011 and 2012 growing seasons. After harvesting, brown rice samples were analysed for their proximates, amino acids, fatty acids, minerals and vitamins. Over 2-year field trials, statistical differences between rice event CPPO06 and its control were found for crude protein, aspartic acid, oleic acid, linoleic acid, linolenic acid, copper and potassium. However, all the tested values for these components were both within the 99% tolerance interval for the commercial cultivars and within the literature ranges. It was concluded that rice event CPPO06 is compositionally equivalent to that of the conventional rice.