For farmers hoping for a healthy harvest, the best place to turn for help these days is the Monsanto Corp. One of the world's leading biotechnology companies and lately a pioneer in genetically engineered seeds--Monsanto has been incorporating flashy traits like herbicide and pest resistance into everything from canola to corn. But such super crops don't come cheap. Farmers pay a premium for Monsanto seeds, and to make sure they keep paying, the company requires them to sign an agreement promising not to plant seeds their crops produce. If farmers want the same bountiful harvest next year, they must return to the company for a new load of seeds. While this arrangement makes sense for Monsanto, it works only if farmers honor it--something that's difficult to police in the U. S. and almost impossible in the developing world. Now, however, Monsanto hopes to enforce biologically what it cannot enforce contractually. With the help of clever genes currently in development, future Monsanto crops may be designed with a new feature in mind: sterility (不育). No sooner will the company's plants mature than the seeds they carry, will lose the ability to reproduce. From Monsanto's point of view, the set of new genes--which others have nicknamed Terminator--is a perfectly legitimate way to protect their intellectual-property rights. Not everybody agrees. Let the new science take hold, opponents ware darkly, and farmers could find themselves coming to Monsanto, seed cup in hand, paying whatever the company demands before they can plant that season's crop. Worse still, some doomsday stories suggest, pollen (花粉)from Terminator plants could drift with the wind like a toxic cloud, cross with ordinary crops or wild plants, and spread from species to species until flora all around the world had been suddenly and irreversibly sterilized. No serious scientist thinks anything so disastrous will come to pass. For Monsanto, however, with a technology in its pocket and a fight on its hands, the situation is about as grim as it can get- at least in terms of public relations. 'From a marketing perspective, it's pathological (病态的). This is a question of who controls the seeds of life.' Before Terminator, farmers ______.