Scientists across the globe are at work yet again, dealing with the Malthusian apprehensions of likely food shortages from rising population pressures on land. Thomas Robert Malthus, who expounded his theory in the 19 th century, is no more, but his warnings still ring prophetic. Around mid-20 th century, scientists had responded to the warnings by ushering in the Green Revolution that pushed yields. Today, the world, facing another food crisis, awaits another long-term solution to the problem.

The Green Revolution, though it made significant strides in increasing food production, was fraught with ill-effects. Excessive use of chemicals caused health and environmental hazards. Extensive tillage and use of chemical fertilisers caused a decline in soil health and factor productivity. Productivity has eventually plateaued.

Now, experts say solutions to the current problems lie in a combination of technologies that can ensure greater productivity along with sustainable and profitable agriculture.

The Food and Agriculture Organisation has called for increasing global rice production by 200 million tonne more by 2025. Scientists are working on developing new rice varieties and hybrids to meet the rising demand for this staple. At present, transgenic technology may not be the answer. The reason: none of the genetically modified crops so far has promised a higher yield; they are only resistant to pests and herbicides.

Experts say what is needed now is a major technological breakthrough that would increase yields of rice and wheat. It means increasing photosynthesis in rice and wheat to the level of maize, sorghum and sugarcane, which primarily means attracting more solar energy to increase productivity. Scientists say, however, that the process would take a decade or more.

Biotechnology tools like marker-aided selection, molecular characterisation, exploitation of apomatic genes, allele mining, harnessing heterosis, and pyramiding of rice genes can be deployed to produce crops of increased potential yield.

The good news is that the availability of rice genome structural sequence has given agriculture scientists the confidence to proceed in these areas. The International Rice Genome Sequencing Project has identified about 56,298 genes.

?After the structural genomics project, scientists are busy identifying gene functions. Once they are identified, it would be possible to develop better crops by introducing genes through traditional breeding in combination with marker-aided selections or through direct engineering of genes into rice varieties,? says a noted plant breeder and World Food Prize recipient, Gurudev Kush.

In a major rice-producing country like India, the annual rate of growth in the output of this staple has tapered off to a level lower than the annual increase in population growth of 1.8%. ?Though the yield potential of rice is 10 tonne per hectare, farmers on the average still harvest five tonne per hectare. To close this yield gap, we must develop varieties with more durable resistance to diseases, insects and tolerance to abiotic stress,? says Kush.

One recent success story is the development of the non-GM rice for Africa with high nutrition content called the New Rice for Africa (Nerica). Nerica varieties, developed by the African Rice Centre (Warda) combine the high yielding quality of Asian rice and the adaptability to local conditions. According to Warda, these new varieties have shown productivity and economic gains.

Noted rice breeder, EA Siddiq, who is the honorary chair professor of biotechnology in Acharya NG Ranga Agriculture University, Hyderabad, believes that immediate concerns over ensuring food security through increased yields can be easily met by using available conventional seeds and hybrids. ?Attempts should be made to bridge the gap between the demonstrated yields of various crops and the actual yields in the farmers? fields,?? says Siddiq.

As for pushing wheat yields, the Indian Council of Agricultural Research (Icar) has joined hands with the Australian Centre for International Agricultural Research (Aciar) and drawn up short- and medium-term strategies.

?This collaboration is not for increasing wheat yields by increasing the photosynthesis to the level of crops like sorghum and sugarcane. That will take considerable time. Our efforts meanwhile are now concentrated on increasing the yield to an optimal level by developing resistances to pests and diseases and several biotic and abiotic stresses,? clarifies Aciar research programme manager Christian Roth.

Besides raising yields, use of technology in other areas can improve the conditions in the farm sector. Better weather forecast, crop condition mapping and computerisation of land records could go a long way in raising farm production.

Timely weather forecast is crucial to agriculture. India Meteorological Department has recently launched a programme for rendering short-term weather forecast for about 680 districts. Such local level weather forecast would be useful to farmers.

Meteorological data of the satellite system?Insat?are processed and disseminated by Insat Meteorological Data Processing System (IMDPS). Data on upper wind circulation, cloud motion vectors, outgoing long-wave radiation, sea surface temperature and precipitation index data are regularly monitored for weather forecasting.

Space technology is also deployed for estimation of crop production, groundwater mapping and mapping of flood and drought areas. The scheme called Forecasting Agricultural Output Using Space, Agro-meteorology and Land Based Observation (Fasal), funded by the agriculture ministry, is implemented by the department of space in collaboration with various state remote sensing applications centres, state agriculture departments and agriculture universities. This scheme undertakes production forecasting of major crops like wheat, rice, cotton, sugarcane, mustard, groundnut and sorghum.

The scheme for computerisation of land records was launched in 1988-98 to provide landowners with computerised copies of ownership, crop and tenancy and updated copies of records of rights (RoRs) on demand. But this scheme has had a sluggish pace.

According to latest records of the Union ministry for rural development, only 13 states, out of 35 states and union territories, can provide RoRs on demand. These states are Andhra Pradesh, Chhattisgarh, Goa, Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan, Tamil Nadu, Sikkim, Uttar Pradesh, Uttarakhand and West Bengal. Technology is seldom tapped to its full potential in India. May be, we need a crisis to wake up to it.