"if cultivation of land is continued without conservation of soil fertility and replacement of large local varieties of plants with one or two varieties, then there will be a disastrous effect, so we must have a 'evergreen revolution' in terms of increasing productivity without perpetuating any associated ecological harm," he said at a lecture at the 100th indian science congress here thursday.

hailed as the father of the green revolution in india, swaminathan outlined the steps needed for a successful "evergreen revolution".

"it can be done by organic farming or what we call as green agriculture which involves integrated pest management, integrated nutrient supply and so on," said swaminathan.

in the context of a green revolution in eastern india, he said water management is the limiting factor.

"eastern india (the land upto bihar) is well endowed with water resources. water is not the limiting factor but water management is a factor. this area can become a fertile belt if a synergetic packet of technology, services and marketing opportunities can be introduced," he pointed out.