Going with the grain: A golden rice breeding method

Despite Southeast Asia sitting at the heart of the world’s rice bowl, scientists are working to ensure food security issues won’t leave much of the region hungry

Sacha Passi
October 10, 2012
Going with the grain: A golden rice breeding method
Strain vault: the medium-term storage room of the International Rise Research Institute's gene bank

Since the dawn of agriculture, crop varieties have been meddled with to benefit the demands of consumers. Prior to the 17th century, almost all cultivated carrots had a deep purple colour with a tough texture and bitter taste. It was not until Dutch growers took mutant strains of the purple vegetable and combined it with yellow and white varieties that the familiar sweet, orange variety was gradually developed.

In the 21st century, food innovation has progressed from the enhancement of aesthetics and flavour to the building of an increasingly globalised agricultural industry to feed expanding populations.

A food staple in Southeast Asia, rice is no stranger to interbreeding to sustain the appetite of the average resident, who can consume more than 150kg of the grain annually. For the region’s poorest members of society, nearly a quarter of whom live under the global poverty line of $1.25 per day, rice remains the lifeblood of daily existence for its ability to feed the masses and provide income. Food security in the region has therefore long focused on sustaining local capacity to take the grain from farm to table, with Thailand and Vietnam dominating the world’s rice exports.

At the mercy of spiking food prices, water security and changing climate conditions, Southeast Asia must invest in viable rice production to protect its strongest link to food security, as the region’s population is set to grow by almost a quarter by 2050, to surpass 760 million.

“It is critical for regional food sustainability that Asean and South Asian countries give high priority to developing efficient and sustainable rice industries, so as to improve domestic and regional food security,” said Rajiv Biswas, an economic expert from IHS Global Insight, a market analysis group. “Within Asean, the Philippines and Indonesia, two of the world’s largest rice importers in recent years, are making progress towards improving their domestic rice production and reducing their dependency on imports.

”With the Philippines and Indonesia expected to lead Southeast Asia’s accelerating population growth, local scientists have turned to high-tech solutions to boost sustainability of rice production in the region.

In August, field tests conducted in the two countries by the International Rice Research Institute (IRRI) revealed the discovery of a gene from the Indian Kasalath rice variety that has the potential to improve the yields of rice growers planting in phosphorus-deficient land.

In the past farmers have turned to phosphorus fertilisers to counteract poor soil quality and increase yields in upland rice fields without irrigation; however, this has proven expensive and environmentally destructive. Successful interbreeding could dramatically reduce this reliance and increase crop yield by almost a quarter.

“The discovery of the PSTOL-1 gene that helps grow bigger, better roots to take up more of the plant nutrient phosphorus can produce 20% more grain than those varieties without it,” said Dr Robert Zeigler, director general of IRRI. “Within a few years, rice breeders will have bred this gene into new rice varieties that will be made available to farmers which will ultimately improve livelihoods.”

Despite the human hand dipping into the pool of natural selection, Zeigler says the agricultural breakthrough is not a product of a genetically modified organism (GMO), but is rather a clever breeding method similar to cross-pollination.

“By selecting the best performing rice plants and using them to breed new rice varieties, rice farmers, and more recently rice breeders, have been changing the genetic composition of rice to generate new and improved rice varieties for thousands of years, resulting in improved quality traits, higher yields, built in resistance to pests and disease and grains capable of coping with droughts and floods,” Zeigler said.

Stuck in a worldwide political and ethical deadlock, genetically modified rice is currently not grown or consumed legally around the globe, despite scientists unlocking the key to enhancing the nutritional value of the grain more than ten years ago.

Golden rice (GR), a product of GMO, where multiple genes have been inserted into the grain’s genome to produce a rice variety enhanced with beta-carotene – the precursor for vitamin A – could, however, be made available to farmers in the region by 2015. “It’s a brilliant piece of science and a major life saving technology,” said Adrian Dubock from the Golden Rice Project.

Rice’s dietary value lies in its high carbohydrate content, which feeds hunger, but the common milled white grain provides little protein and low levels of essential vitamins needed to achieve a nutritious diet.

It is also completely devoid of vitamin A, a nutrient necessary to protect children and pregnant and lactating women from diet-related blindness and increased susceptibility to preventable infections and diseases that can lead to death.

“Severe vitamin A deficiency is usually indicative of poverty, children that are so poor that all they eat is rice,” said Dr Michael Hansen, a food safety expert from Consumers Union. “In the long term, people need to eat a more diversified diet, as many foods are naturally high in vitamin A.”

One whole baked sweet potato, for example, provides nearly three times the recommended daily intake of vitamin A for a child under the age of nine, but despite the crop’s large presence in Vietnam, Indonesia and the Philippines, much of the vegetable is destined for animal feed or further processing.

In Southeast Asia, the Philippines is leading the way for GMO produce and is one of only two countries in the world where GR seeds have been accepted for further research studies.

Despite scientific evidence to support the commercialisation of the grain, the project has been marred by controversy surrounding the scientific process used to alter food composition. “The delivery of potential benefits to the affected populations have been delayed by very strong technophobic and political reaction against the genetic engineering technique,” Dubock said. “Genetic engineering allows crops to be modified to benefit man, and is yet one more tool in the plant breeder’s toolbox.”

In 1990 the Philippines implemented a regulatory system for transgenic crops – the first country in the region to apply biotech guidelines – but remains only one of two countries in the region to generate commercial GMO produce.

Between 2003 and 2010, biotech farming in the Philippines contributed $170m to the farming industry through the production of commercialised GMO maize – which is most commonly used as feed for livestock. The developing industry however still only accounts for a marginal portion of the country’s total agricultural GDP of $25 billion.

Following successful trials of GR, Dubock predicts farmers in the Philippines could be some of the first in the world to commercially produce the grain once nutritional evaluation is complete. “I think we can be working with farmers there in three or four years,” he said.

More than twenty years in the making, getting GR to market evidently has a few more hurdles to overcome. Extensive data demonstrates the negative impact GMOs can have on the environment; however, the strength of the GR grain lies in the fact that it is developed to enhance nutrition rather than resist herbicides and pesticides, which make up for 80% of all GMO produce.

Food safety expert Dr Hansen argues that fighting the prevalence of vitamin A deficiency does not lie in the power of one grain, rather the ability to address larger scale issues facing the region. “To really cure the most serious cases of vitamin A deficiency one must tackle the root cause, which is poverty,” he said.

Perhaps the same can be said for Southeast Asia’s future food security as a whole.

With a finger firmly on the pulse of scientific technology, protecting the humble rice grain is clearly on Southeast Asia’s agenda, not only for its ability to feed hungry mouths, but to support the region’s largest crop export. Time, however, will be the ultimate indicator for the region’s ability to ensure sustainable food production moves in tandem with the growth of the region’s population.

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