This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

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Sunday, May 11, 2014

A New Revolution in Rice

The Green Revolution has helped food keep pace with population growth since the 1960s, but the momentum has slowed considerably. This week's Economist, however, reports on a new strain of flood-resistance rice developed at the same International Rice Research Institute (IRRI) in the Philippines that helped give rise to the Green Revolution. Here's the problem, as the Economist sees it:
Without new seeds, yields will decline further. Global warming will tend to push harvests down: higher night-time temperatures are associated with lower yields. The richest rice-growing areas in the world are the deltas of Asia’s great rivers, such as the Mekong, Brahmaputra and Irawaddy; they are vulnerable to rising sea levels and increased salinity, which kills rice. The plant uses two to three times as much water as other cereals (largely for levelling the paddies; the plant itself consumes no more than wheat or maize), but water is scarce everywhere. And each year the spread of Asian—especially Chinese—cities converts millions of acres of good rice-growing land into buildings and roads.
And now the solution:
Farmers will not adopt a single miracle variety. Instead, researchers will tailor seeds for particular environments (dry, flooded, salty and so on). And they are also trying to boost the nutritional quality of rice, not just the number of calories. As a result, the second revolution will be felt most profoundly in the poorest areas and among the poorest farmers. In contrast, the first had the biggest impact in the richest fields, with the most water and fertiliser. 
The flood-resistant trait that rescued Mr Pal’s crop was first identified in the 1980s, in a few old-fashioned varieties native to Odisha, another flood-prone state in eastern India. After more than a decade of false starts, plant scientists identified the genes that make the Odisha varieties flood-tolerant. They went back to IR8’s descendants, spliced these genes into them and bred from the result. Having spent years getting nowhere with traditional plant-breeding methods, scientists went from marking the genetic sequence to producing flood-resistant seeds in four short years.
As the Economist itself points out, this is less a second revolution than an evolution of the first Green Revolution, but it is an important piece of good news as we contemplate how to cope with the coming billions of people.

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