Combating Deficiencies With Biofortified Rice

For over half of the world’s population rice is a staple crop, this is particularly true in tropical countries of Africa, South America, and Asia. Rice grains are not rich sources of vitamin B1 to begin with, and the processing steps reduce the levels even further, removing 90% of them, further contributing to chronic deficiencies. 

Researchers at the University of Geneva (UNIGE), in collaboration with teams at ETH Zurich and Taiwan’s National Chung Hsing University (NCHU) report in Plant Biotechnology Journal, making a significant advance in the fight against this deficiency by developing a rice line enhanced with vitamin B1 in the endosperm of rice without compromising agronomic yield, which could help to solve the major health concern in regions where rice is the staple food.

‘‘Previous attempts at biofortification by other teams had succeeded in increasing the vitamin B1 content of the leaves and bran - the outer layer of rice grains - but not that of the ready-to-eat rice grain. In our study, we specifically targeted the increase in vitamin B1 content in the endosperm,’’ explains Teresa Fitzpatrick, first author of the study. 

After growing the rice line in a glasshouse in Taiwan, harvesting and polishing the rice grains, the vitamin B1 content was found to be increased in these lines compared to those that had not been biofortified. Additionally, plant height, number of stems, grain weight, and fertility were all comparable, and the level of vitamin B1 was multiplied by 3 to 4 times in the modified lines after the polishing stage without impacting crop yield. 

According to the researchers, one 300-gram bowl of the biofortified rice provides around a third of the daily recommended daily intake of vitamin B1 for an adult. While this likely isn’t needed in Western countries, the development could be a welcome addition in nations that eat rice more often. If this could be done on a larger scale it could enhance the health of millions of people around the globe. The next steps will be to pursue this approach in commercial varieties after regulatory steps relating to biofortification by genetic engineering have been taken to cultivate commercial varieties. 

“Most studies of this type are carried out with glasshouse-grown crops. The fact that we have been able to grow our lines under real field conditions, that the expression of the modified gene is stable over time without any of the agronomic characteristics being affected, is very promising,’’ enthuses Wilhelm Gruissem, Professor emeritus at ETH Zurich and Distinguished Chair Professor and Yushan Fellow at NCHU.