Gurdev Singh Khush: masterminding a new rice revolution

UNESCO Courier, June, 1999 by Ethirajan Anbarasan

An architect of the Green Revolution(*) is now trying to bring about a "Green Green Revolution" to avert a food crisis in the coming decades

Experts have warned of a possible food crisis in Asia in the coming decades due to population growth combined with lowered rates of food production. Is there a possibility of famine surfacing again in some Asian countries?

The Asian region will definitely face food shortage some time in the future if present trends continue. In most Asian countries, where the staple food is rice, population growth has not yet stabilized and the demand for food is increasing. According to UN estimates, by 2020 the world population will have swollen to around 8 billion people, 5 billion of whom will be rice consumers. We estimate that the world's rice harvest must increase from the present 560 million tonnes to 840 million tonnes per year to meet the demand. All this has to come from existing agricultural land, as no more cropland is available in many countries. While increasing food production, the Asian countries should also think about active population control programmes.

How fast is food growth increasing to meet the demand?

Unfortunately food production is not keeping pace with population growth. Between 1960 and 1990, global food production was increasing at a rate of 2.8 per cent per year while population grew at a rate of between 2.1 and 2.2 per cent. So there was not much of a problem. However, the situation changed in the 1990s. Now population is increasing at the rate of 1.8 per cent whereas food production is growing at a rate of 1.5 per cent per year. Investment in irrigation has virtually ceased and good land is being lost to industrialization. If present trends continue, it will not be possible to meet future demand for food.

To what extent can new technologies help to boost yields? Where is rice research heading?

We now have rice varieties which have a yield potential of about 10 tonnes per hectare. However, the present average yield of irrigated rice in Asia is around 5 tonnes per hectare under best management. To increase the average output to 8 tonnes, we have to fine-tune the production system and invest more in irrigation and in educating farmers about new technologies. We are confident that by early in the next century, new seed varieties with a yield potential of 12 to 12.5 tonnes per hectare will be available.

The future of rice research will be oriented more towards eco-friendly agriculture. Rice breeders worldwide are now developing new rice plants which are drought-resistant and pest-resistant, and have the inbuilt capacity to outgrow weeds. In the next 30 to 50 years, temperature-sensitive rice plants will also be needed with tolerance to higher temperatures because of global warming.

What is the next step for the International Rice Research Institute (IRRI)?

At the IRRI, our next aim is to bring about a "Green Green Revolution" to produce more rice from less land and water, and without chemical pesticides or herbicides. For this we have developed a new plant type, called "Super Rice", which is in the experimental stages. This new plant, a product of conventional breeding methods, will have an entirely different architecture from that of our earlier seed varieties.

In IR8, the first high-yielding rice variety, half of the plant's weight is grain and half is straw, whereas the new Super Rice plant is 60 per cent grain and 40 per cent straw. This new variety will have increased photosynthetic capacity, directing more energy into grain production and less into foliage. An early prototype of this new plant was developed a few years ago and now we are working to improve the grain quality and to incorporate genes that will give the seed variety disease and pest resistance so that farmers won't have to use pesticides. For the first time, we have "borrowed" the gene that gives maize its stem strength and introduced it into the new plant. This will enable the plant to carry more grains, increasing the yield by at least 25 per cent compared to existing varieties. We hope to release it to Asian farmers by early next century.

When you started your career at the IRRI 32 years ago, the primary aim was to develop high-yielding rice varieties to prevent a food crisis. That led to the Green Revolution. Then came eco-friendly agriculture and now efforts are being made to develop genetically modified seeds. How would you describe this transition?

Asia witnessed acute food shortages in the 1960s and it was urgent to step up food production. This was achieved by developing high-yielding rice varieties like IR-8, IR-36 and IR-64 at the IRRI which matured in 110 days compared to the 180 days required for traditional varieties. This transformation, better known as the Green Revolution, helped to double rice production in Asia between 1967 and 1992, averting famine in many countries. In some countries like Indonesia, rice production trebled. However, it was realized during the process that indiscriminate use of pesticides and fertilizers caused environmental damage. So the emphasis shifted towards sustainable agriculture. Farmers were encouraged to use organic manure, compost and bio-fertilizers. Subsequently new seed varieties, genetically resistant to certain insect pests, were also developed, minimizing the use of hazardous pesticides.