Monday, January 17, 2011
A New Rice Revolution on the Way?
Get ready for Green Super Rice
The world appears to be on the threshold of another green revolution in rice production as a result of an intensive, 12-year partnership between the Chinese Academy of Agricultural Sciences in Beijing and the International Rice Research Institute in the Philippines.
Called "Green Super Rice," it is the result of a project begun in 1998, involving the painstaking crossbreeding of more than 250 different potential varieties and rice hybrids, according to Dr Jauhar Ali, a senior scientist and regional project coordinator for the Development of Green Super Rice at IRRI in Los Banos, south of Manila.
The development of the process, Dr Ali said, is considered so significant that Microsoft founder Bill Gates met personally with Zhi-Kang Li who holds a dual position both with IRRI as Senior Molecular Geneticist and as Chief Scientist with the Institute of Crop Sciences at the Chinese Academy of Agricultural Sciences in Beijing and, through the Bill and Melinda Gates Foundation, presented the program with a US$18 million, three-year grant to expand the benefits to Asia and Africa.
The two institutions are seeking additional donors to be able to push the rice to undeveloped corners of Africa and other continents to help stave off the growing need for food across the planet.
The process was developed by Zhi-Kang Li, It involves the efforts of hundreds of researchers in dozens of countries across the world, seeking to isolate the desirable traits from indigenous strains and then backcross breed them to produce hardier varieties.
Particularly, Dr Ali said in a telephone interview, the method of producing the new strains of rice is as important, or perhaps even more so, than the strains of rice themselves, because it holds out the hope of a scientific method of increasing yields of other crops, making them hardier and more resistant to disease and insects and cutting the use of fertilizers and pesticides without resorting to genetic modification. Importantly, since it was developed by public institutions, it is not subject to the onerous conditions that major agri-chemical companies like Monsanto place on farmers, including the need to buy new seeds every year.
The development comes at a time when food security has become a major political issue, not just in Asia but increasingly across the world as the price of commodities skyrocket. Disastrous floods in Pakistan, drought in Australia, fires and drought in Russia, all combined to spur concern that the world could be on the brink of a food crisis to rival that endured in 2007, when the price of rice shot from roughly US$250 to US1,100 per ton before falling back to hover around US$500 today. Imbalances in the demand-supply chain and hoarding by national governments have forced the World Food Program to initiate a number of emergency projects to continue the delivery of food to the world’s poor. Rice in particular faces problems from climate change.
It has been a long, hard slog to come out with the concept of Green Super Rice, Dr Ali said. It started in 1998 with the launch of an international rice molecular breeding program originally involving more than 18 countries and 36 institutions. However, there was no funding to continue the program and it ultimately died out in all of the countries and institutions except for IRRI and the Chinese Academy.
Green Super Rice does not involve genetic modification. Instead, it involves taking hundreds of donor cultivars from dozens of different countries, identifying significant variations in plant response to drought, global warming and other problems, and "backcross" breeding – painstakingly crossing a hybrid with one of its parents or with a plant genetically like one of its parents, then screening the backcross bulk populations after one or two backcrosses under severe abiotic and biotic stress conditions to identify transgressive segregants that are doing better than both parents and the checks.
This operation is done for all the backcrosses originating from 46 recurrent parents and 500 donors -- a mini-core collection - and reconfirmed before further pooling them across different traits by the use of molecular markers to improve rice tolerance – for instance, drought, salinity, submergence, rice blast fungus, bacterial leaf blight and the ability to out-compete weeds, reducing the need for fertilizers.
"The idea is that now we have a wider range of materials that can combat drought and submergence, we now have lines that are tolerant to all known races of blast and bacterial leaf blight at IRRI," Dr Ali said. "We have confirmed that we are on the third round for testing."
The announcement comes on the 50th anniversary of what has been called the original Green Revolution, when IRRI, established by the Philippine government and the Ford and Rockefeller Foundations, introduced IR8, the first "miracle rice," as it was called then, to the world, at a time when India especially was on the brink of mass starvation. IR8, a semi-dwarf variety, yielded about 5 metric tons per hectare without fertilizer and as much as 10 tons under optimal conditions – about 10 times the yield of traditional rice.
IR8 was subject to kernel breakage and other problems. But eventually, its successors revolutionized world food production, driving down the price of rice by more than 50 percent and turning India, Thailand and other countries into some of the world’s most successful producers and exporters. The Philippines, where IR8 was developed, became rice sufficient for several decades, with production increasing from 3.76 million tons to 7.7 million in two decades, before slipping into deficit again.
Rice is grown on some 142 million hectares in Asia, feeding more than 4 billion people. A semi-aquatic plant species that originated in tropical swamps, rice production typically consumes two to three times as much water as do other cereals. Thus water deficiency – drought – has been the single biggest limit in rain-fed rice fields, with drought at the early stages of growth causing delayed transplant or delayed germination. Drought at the reproductive stage also slows growth, according to a variety of papers made available by Dr Ali, resulting in low and unstable rice productivity. Also, IR8 yields have dropped by about 15 percent as hotter nights produced by climate change impede growth, according to Dr Shaobing Peng, an IRRI research scientist.
IR8’s successors used far more fertilizers and pesticides than conventional strains, but produced substantially higher yields. The extensive crossbreeding, which was developed by Zhi-Kang Li when he was a researcher at IRRI before moving back to Beijing, was partly developed as an effort to reduce the dependency of the new rice strains on fertilizers and pesticides. It appears to be succeeding.
In one study, for instance, researchers backcross bred three recurrent elite rice lines and 203 diverse donors, representing a significant portion of the entire genetic diversity of the primary gene pool of rice over six years to improve tolerances to salinity, submergence, zinc deficiency, resistance to brown plant hopper and other problems.
Such efforts are coming under an umbrella organization called the Global Rice Science Partnership, under the acronym GRiSP, launched last November at the third International Rice Congress in Vietnam, which seeks to enable the world to coordinate its approach to rice science so that agencies can pool their resources, apply their expertise and collaborate in the delivery of the improved strains to poor rice farmers across the world. GRiSP is looking for the funds to expand into seven countries across Asia and seven in Africa. Some 260 people have been trained from public and private centers, including in Africa, on the use of the Green Super Rice breeding and seed production technology. Written by John Berthelsen