Vitamin A-loaded rice

The Philippine Rice Research Institute (PhilRice) is pushing hard for the development of rice varieties with a considerable amount of vitamin A in their grains through bio-fortification to help combat night and total blindness, especially among children.

"Any increase of vitamins and minerals in the rice grain can bring health benefits to millions of malnourished people who depend mostly on rice for nourishment," said Emily Corpuz-Arocena, a plant breeder at the PhilRice Plant Breeding and Biotechnology Division.

Dr. Antonio Alfonso, a molecular biologist and the chief of the division, said well-milled white rice, which provides 80 percent of the calories we take in, contains almost negligible amounts of micronutrients and vitamins. And yet only a few Filipinos nowadays, including the poor, eat un-milled brown rice, which contains small amount of micronutrients.

At present, two out of 10 pregnant and lactating Filipino women and four out of 10 children, six months to five years old, suffer from vitamin A deficiency. About four million pre-schoolers are at risk of going blind and 4,000 children die every year from the effects of vitamin A deficiency. These most vulnerable population groups often show serum vitamin A levels that are way below the World Health Organization cut-off points.

Since rice is the staple food of Filipinos, vitamin A biofortification in rice is deemed as the best solution in solving vitamin A deficiency, Alfonso said. Through vitamin A biofortification, rice is developed specifically to produce vitamin A in the grains.

Biofortified rice can easily reach the rural areas and would entail much added cost to the poor people who could not to buy supplements and fortified non-staple foods, which are costly.

Vitamin A is a very important micronutrient to humans. Among adults, micronutrient deficiency, also called hidden hunger, reduces labor productivity. Likewise, it diminishes the ability of children to learn, as well as increases death rates and disease infection. Furthermore, it reduces the livelihood and quality of life of all those affected.

PhilRice scientists are approaching the development of vitamin A-loaded rice varieties in two ways.

One, they have crossed the popular variety PSB Rc82 with Cocodrie, a Golden Rice variety developed through genetic engineering in the United Kingdom by Syngenta, a multi-national company. Current versions of Syngenta’s Golden Rice that have the genetic background of the rice variety Kaybonnet contain 23 times more beta-carotene than the original Golden Rice, which contains utmost 1.6 micrograms of carotenoids per gram.

Golden Rice, said a research report published in Nature Biotechnology, is the name coined to describe the genetically modified rice that produces beta-carotene (pro-vitamin A) in the edible portion of the rice grain (endosperm), giving rise to a characteristic yellow color. The variety was engineered to combat vitamin A deficiency and has been predicted that its contribution to alleviating vitamin A deficiency would be substantial through higher beta-carotene content.

Seeds of Golden Rice 2 were provided to PhilRice by the Humanitarian Board, which is chaired by Prof. Ingo Potrykus, one of the breeders of the original Golden Rice.

Alfonso said the first-generation offspring of PSB Rc82 x Cocodrie will be backcrossed to PSB Rc82 three to four times to come up with stable lines that are now capable of producing beta-carotene.

At present, the offsprings are being grown under screenhouse condition under the supervision of the National Committee on Biosafety in the Philippines (NCBP). Thereafter, the seeds will be tested in the field for yield performance as well as for its effects on human health and the environment.

Cocodrie and Kaybonnet will also be crossed with NSIC Rc128 (Mabango 1), the first aromatic rice variety bred by PhilRice.

The second approach taken by PhilRice scientists is to develop new rice varieties with bacterial leaf blight and tungro disease resistance and with high concentrations of pro-vitamin A through conventional breeding.

At present, bacterial leaf blight and tungro could inflict heavy damages during heavy infestation. — PhilRice