Now there's a new entrant to this club - and one that could turn out to be the most important of them all. Scientists have deciphered the genetic make-up - genome - of the tiny flowering weed, Arabidopsis thaliana. The decoding of the genome of a plant for the first time promises to usher in a revolution in man's understanding not only of plants, but also of all other forms of life.

The genome is the biological instruction manual for how an organism forms and how its cells function. Genes are the founts of proteins that make a cell what it is. By unscrambling this scrambled biological word game, scientists have set the stage for spectacular advances not only of the botanical kind, but also in human genetics and medicine, since more than a quarter of all medicines are derived from plants. Thus the Arabidopsis genetic map shows some 100 genes closely related to the buman disease genes.

Many of these have to do with such hereditary afflictions as cancer, deafness and blindness. This apart, the Arabidopsis project is bound to lead to vast improvements in commercial crops, some of which may soon be able to produce even biodegradable plastics. Then there are the genes that govern the synthesis of oil in Arabidopsis. It may not be long before designer plants with more desirable oils become the order of the day.

The effect of the gas ethylene on plant development is another good example. Scientists have long used it blindly to check the ageing of flowers and slow down the ripening of fruits. But while cracking the Arabidopsis genetic code, they identified the gene that controls the biological effects of ethylene. So a mutant form of that gene which prevented normal plant response to ethylene was created in the lab. By introducing this altered gene into tomato plants, researchers have made them unresponsive to the retardant influence of ethylene. The logical next step now would be fruits which ripen at one's will and flowers that never wilt.

Editorial in The Hindustan Times