Asia faces a major shortfall in food production in the coming decade unless there is a drastic revision of development strategies in the region, according to an analysis prepared for the Asian Development Bank.

The study urges the less-developed countries to shift the emphasis in their development plans from urban-industrial projects to rural-agricultural ones.

If these countries continue as they have been, the study warns, the region faces a shortfall of 24 million to 30 million tons in such key grains as wheat, rice and corn. The study goes on to predict that unemployment rates in the poorer countries may rise to 20 per cent by the end of the decade.

Two countries, South Korea and Nationalist China, are credited with moving in the right direction, with the result that their rural populations have shared in their countries' rising prosperity. Although the report does not mention them specifically, Burma, Pakistan, Indonesia, the Phillippines, Afghanistan and India are understood to be among the more important Asian nations that have concentrated on industrial development and neglected their rural sectors.

As it is, Asia was scarcely able to keep food production rising in step with its population increase over the past 10 years, the study reports. In some contries, however, per capita output fell despite the introduction of new technology. In the region's poorer countries, most of the population "does not consume the minimum dietary requirements for normal health."

The study found that technical innovations in agriculture over the past 10 years - high-yield strains, mechanization, irrigation - have resulted in little benefit for the rural masses. In fact, rising population figures combined with the recent high rates of infaltion have held down or even reduced the level of real wages over the past decade.

"The majority of households in [less-developed countries] lack even the purchasing power to obtain an adequate diet," the report says. The low incomes suppress demand not only for agricultural products but for goods and services from the cities as well.

The study urges the priority be given to boosting the incomes of the rural poor. Any of the specific measures it proposes would have considerable social and eonomic consequences. Cumulatively, however, the proposals would have far-reaching impact on the political systems typical in the power countries of Asia.

The proposals are:

Projects to stimulate employment in rural areas.

Access to land ownership by the rural poor.

Access to financing by the rural poor.

Creation of farmers' associations.

Decentralization of expenditures and decision-making on the part of the national government.

One top official with an international organization calls the survey's suggestions a blueprint for a "breakdown in the feudal system" typical of rural areas in poorer Asian nations. "These proposals," he said, he said, "are like asking countries to cut their own throat" because they would involve a massive shift of power to the rural area.

By background, training, and inclination, the development officials of the poorer countries - and the technocrats of the Asian Development Bank - have a bias toward projects that have the greatest impact in the cities. Moreover, the rich donor countries tend to favor programs that result in export sales of them; these generally involve heavy industrial equipment or other materials likely to end up in urban areas.

In addition, the Asian Development Bank has, with few exceptions, loaned only to cover the foreign exchange costs of a given project. Should the bank support the recommendations of the agricultural survey, it would cover the local currency costs of rural development programs.

Nevetheless, officials in both the bank is member countries have expressed concern that the rural poor have received little benefit from the millions that have gone into development schemes. As an example of the new thinking, several countries have abandoned policies that had been designed to put cheap food on the table of the urban worker but whcih also made the return to farmers artificially low.

Experts doubt that the full panoply of recommendations put forward in the survey will be adopted - the potential of social upheaval is too great. On the other hand, they do expect the survey to bolster the hand of those officials in Asian countries who have been arguing for increased emphasis on rural development.