Surinder Sud: Meeting the rice demand

FARM VIEW

The production rate needs to be doubled to ensure sufficient availability. Thankfully, rice technologists are doing the needful.

Though the availability of rice, unlike that of wheat, has not been a problem so far, the situation might change if the growth rate in rice production does not rise. At present, the annual output growth in this key foodgrain is below one per cent, against the population increase of around 1.7 per cent. So, unless rice production rises at nearly double the current rate, its availability may not remain comfortable for long.

The silver lining, however, is that rice technologists are conscious of it and have already begun fine-tuning their research strategies to meet this goal. This was evident at the 2nd International Rice Congress, held recently in Delhi, where rice scientists, millers and traders from some 45 major rice-growing countries outlined the efforts underway to raise production and productivity of better quality rice at relatively lower costs.

The most interesting and potentially significant line of action relates to altering the genetic constitution of the rice plant to enhance its inherent production capacity. Something similar was done earlier as well by exploiting the dwarfing gene that helped evolve the rice varieties which triggered the green revolution in this crop.

This was followed by the evolution of hybrid rice, which led to several folds, increase in rice output in China and is now slated to do the same in India. About 27 rice hybrids, including 22 from the public sector and five from private companies, have already been released for commercial cultivation in India. Most of these have a yield advantage of between one tonne and 1.5 tonnes a hectare.

But more exciting than all this is the programme now underway to recreate the rice plant. The new plant being conceived will have more and much larger earheads (spikelets) to accommodate higher number of grains and much shorter stem so that most of the nutrition goes into grain development, leading to higher yield per plant.

The other equally exciting research is for upgrading rice from the current C-3 type plant to the C-4 type. Simply put, this will make the plant a better converter of carbon, solar energy (photosynthesis) and other nutrients into grains. Plants like maize and sugarcane are C-4 type plants. According to Indian Council for Agricultural Research (ICAR) Director-General Mangala Rai, efforts towards this end are now afoot in many places. The Philippines-based International Rice Research Institute (IRRI) proposes to spend about $1 million for this research effort, in which India will be a partner. However, as pointed out by Rai, such research, by its very nature, is a long shot and could take 10 to 15 years to fructify.

Indeed, many scientists who attended the global meet felt that the prospects of a genetic revolution are far brighter in rice compared to other plants. For, rice is the only plant so far whose genome has been fully mapped in a project jointly carried out by several countries, including India. Once the precise functions of each of the 5,600 identified genes are fully understood, it will become possible to exploit them for creating tailor-made plants for specific objectives, such as drought or flood tolerance and disease or pest resistance.

Interestingly, the gradual unveiling of the nature of genome of wheat, another equally important food crop, has revealed that several genes are common or similar in both wheat and rice plants. Some researchers have also found similarities in the chromosomes of certain plants and living beings. "Indications that seven wheat chromosomes are evolved from 12 ancestral rice chromosomes, coupled with the unfolding of the genetic make-up across plant and animal kingdoms, have enhanced the possibility of imparting immunity to wheat against the dreaded rust diseases and conversion of rice from C-3 to C-4 type plant," Rai maintains.

However, in the shorter run, the increase in rice harvest is possible through increasing water-use efficiency, reducing losses from diseases and pests and adopting better cultivation practices. Millions of tonnes of additional rice can be harvested by improving the water-use efficiency from the present 40 to 50 per cent to a higher level of, say, 60 to 70 per cent or more. Expansion of area under hybrid rice could also facilitate higher production and more profits for rice growers. But for this, mass production of hybrid rice seeds, a sophisticated job, would have to be ensured through involvement of the private sector.