He bred new strains and varieties of plants, including fruits, flowers, and vegetables over his 70 year long career.

Farmers have always tried to breed better strains.

There have already been instances in which bacteria and viruses breed drug-resistant strains.

Disease control focuses on containing infections and breeding resistant strains, and is the subject of much ongoing research.

It was not so long ago that children even younger than Kristlin were forced into matings in order to breed exotic new strains of laran.

It simply does not help the child and increases the risk of breeding more resistant strains of bacteria," says Ehrlich.

Pioneer's basic strategy has been to breed high-performance strains of corn and other plants, then charge farmers a premium for the seeds.

But scientists say the diverse varieties of traditional crops and wild plants they need to breed more productive new strains are in jeopardy.

Breeding new autoflowering strains becomes more difficult when attempting to make a hybrid with a non-autoflowering strain.

Water supply experts yesterday said this finding added to their concerns that such contamination could be helping to breed resistant strains of bacteria.