Jan 12, 2007
A miracle rice
How seductive are those emerald green fields of the Indian countryside, with waving paddy shoots modulated by even little breezes. The acres of water in which they stand tempt you to linger and inhale the cool heady smell.
Sorry to intrude, but your rice field is causing good-sized environmental violence. A kilo of rice on your table needs 5,000 litres of water to grow. And the rice plant produces a lot of methane, which is a greenhouse gas.
The good news is we may be on the threshold of being able to grow rice in a more ecologically sensible way. A new rice plant, christened Aerobic Rice has been developed that promises much. Traditional rice cultivation is termed an-aerobic because standing water causes decomposition of organic matter in the absence of oxygen and this process generates methane. It is estimated that up to 25% of all methane generated in the world is from rice fields.
But aren’t flooded fields required to grow paddy? Well, no, not if you grow the right kind of rice. And there were in India, several strains of rice that grew well with little water. How? They had strong and vigorous root systems that absorbed moisture from below the surface.
The Green Revolution is lazy farming with appropriate costs all around. The high yielding variety of rice that led the revolution, had short roots which had to be pampered with water without it having to make the effort. Ergo, flooded fields. This was deemed good plant efficiency, when measured in terms of rice yield per given weight of plant. But no one worked out total efficiency and cost of agriculture. Floods of water, energy to pump it, fertilisers and pesticides to force feed the plant and keep it alive, the net profit to the farmer and of course the net loss to the planet in terms of methane generation were not reckoned with. Even worse, where once farmers grew rain-fed rice and other crops that needed little water, they now came to believe agriculture was not possible without a river or a well near puddled fields. Large acreages that were once farmed were abandoned.
The search for a rice that yielded good profit with little water began six years ago. According to a report in 2002, five Indian institutions and 20 scientists began work under a $350,000 grant from the Rockefeller Foundation. They began with 3,000 native genes from which 800 were found promising. Then hybridisation of various combinations were tried.
In Nov 2006, Prof H E Shashidar of the University of Agricultural Sciences [UAS], Bangalore, one of the five institutions doing research, announced the development of Aerobic Rice. This has three times the length of currently cultivated rice strains, requires half the water and yields are about the same. It can grow in purely rain-fed conditions, can be broadcast directly in the fields which means the cost of transplanting is avoided. With reduced labour and energy costs, net profit for the farmer increases. Being aerobic, methane generation is nearly nil. Anaerobic rice, standing in water and fattened by fertilisers attract pests to their succulent stalks. The miracle -aerobic- rice is austere and so pests keep off. An added bonus is that aerobic rice growers may get an additional income by claiming carbon credits.
UAS has developed six types of aerobic rice that are set to be released to farmers in the coming year which could lead agriculture in a wholesome direction.
Almost on the same day as this story went online, world media carried news that seems to stand the methane theory mentioned above, on its head. GoodNewsIndia is indebted to reader Kris Rallapalli for bringing this to our attention.
According to a research report published by the Max Planck Institute of Nuclear Physics at Heidelberg, Germany, anaerobic conditions, such as flooded paddies, are not necessary for methane production. Even ordinary plants, in rich oxygen realms, exhale substantial quantities of methane; in fact 30% of the whole methane production!
Fearing that this piece of news might trigger a blame game on what causes greenhouse methane, the Institute on Jan 18, 2007 released an explanation of the whole scene. It argues that plant derived methane has formed a non-threatening methane baseline ever since the planet began to support life forms. The discovery that plants even in aerobic conditions produce methane, does not add to the methane load but only increasses our understanding. The gobal warming crisis is clearly due to the rapid increase above baseline caused by fossil fuel burning. Planting more trees certainly remains a non-threatening idea.
And the bottomline on miracle rice? By reducing methane even further than in flooded paddy conditions, aerobic rice is a part of the solution and not the problem.