Tokyo — Farmer Kyoshi Bannai rarely has to go near his fields or get his hands dirty. He simply sits in front of a computer console in his modern farmhouse controlling his crops by remote control.
Mr. Bannai is in the vanguard of a belated technological revolution in Japanese farming. Computerized crop growing, robotics, genetic engineering, and seed cloning - this is the shape of things to come.
Tradition-minded farmers sneer at such advances, regarding them as expensive toys invented by city slickers with nothing better to do with their time. To others, however, the developments are not only logical but also very necessary.
One reason is the rapidly advancing age of Japanese farmers. The nation in general is growing old fast as birthrates slump and people live longer. On the farm this is exacerbated by the departure of the younger generation, which is more interested in well-paying jobs in the city than in backbreaking, dirty contact with the soil.
But the technology that has transformed Japanese industry into a powerful world force has been late in reaching the countryside.
Partly this is due to a concentration on rice growing, the limited nature of other crop farming, and heavy dependence on imports (with the United States the No. 1 supplier) for almost everything but rice.
Rural productivity lags well behind that of the industrial sector. Inefficient Japanese farmers could not hope to survive international competition without heavy government subsidies and the protection of import quotas.
Farming must be ruthlessly reformed to be competitive, the government has decided. And for this to succeed a heavy dose of advanced technology is needed.
Near Sayama, a Tokyo ''dormitory town,'' Kyoshi Bannai acts as a guinea pig. After a great deal of careful deliberation, he has fed a crop-growing program into his computer.
Optical sensors in the fields feed information back to the computer to indicate how things are going in the soil. In turn, the machine controls the fertilization or other crop-growing conditions. Apart from emergencies, Mr. Bannai, a descendant of an ancient farming family, has to go out into the fields only at harvest time.
And even there, science is getting ready to take over: Leading agricultural machinery manufacturers are developing automated tractors, combines, and other machines.
Some already operate without a driver. Others respond to voice commands by the human operator, with a synthesized voice able to ask questions when the machine's computer is not sure what to do.
Japan's Industrial Robot Association envisages widespread robotization within this decade of farms for chemical spraying, fertilization, cultivation control, and many other traditionally dirty, backbreaking jobs.
At a research center in Tsukuba, some 45 miles north of Tokyo, the Ministry of Agriculture has built an experimental farm that operates without any human workers. It features a 30-foot wide computer-operated gantry running over a plot of land doing everything from drilling and sowing to the final harvesting. A rice-growing test this year resulted in a yield 19 percent above the national average.
Meanwhile, with a combination of American and Japanese technology, various experimental ''farm factories'' are being established to mass-produce vegetables and crops around the year regardless of the weather.
A central computer feeds water and liquefied fertilizer to seed beds at regular intervals. One system, designed for cold northern climes, uses lamplight to raise vegetables in only five days. The big drawback: heavy electricity bills.
The high cost is the biggest problem with many of the systems now under development. A spokesman for the Agriculture Ministry says: ''The challenge now is to bring these innovations within the scope of the average farmer's tight purse.''
Farmer Bannai adds: ''Many people scoff at the idea of high technology in farming because of the high cost. Eventually, however, the price has got to come down, and then I think computerization and robotization are inevitable.
''We've got to be able to produce more to increase Japan's food self-sufficiency, while reducing our very high costs. You cannot do that with old-fashioned, labor-intensive methods.
''These days, anyway, it's getting harder to find people to work on the farms. This could offer a chance to consolidate the present inefficient small farming units typical of this country, and take full advantage of mechanization and new technology.''