WHY COLLECT PLANTS WHEN YOU CAN MAKE THEM?

A Lecture by Professor John Beringer, University of Bristol, on 14 July 1998
Professor Beringer is Dean of the School of Biological Sciences at Bristol, and Chairman of the Advisory Committee on Releases to the Environment

“Paradise transported” neatly sums-up the extraordinary bringing together in our gardens of so much beauty in the form of plants from other regions of the world. However, as we all know, major changes in the types of plants we can grow are unlikely to come from plant collecting because most plants capable of growth in temperate regions have been tried in the UK. The future would, therefore, appear to offer only minor improvements to existing well-loved species with novelty being something only previous generations of gardeners could benefit from. Modern genetics, however, will allow scientists to produce novel plants. For example, by introducing genes for frost tolerance from a fish, the arctic flounder, we could modify tropical plants so that they could be grown in the UK. Plants could be made resistant to pests and diseases, so that roses are not infested with greenfly and black spot fungus, or modified so that flowers and fruit last longer or have different shapes or colours.
Until now such changes have been achieved slowly by cross-breeding and selection; genetics allows the process to be speeded up many times - at a cost. Extracting DNA from a plant is easy, it can be done in the kitchen; separating and selecting the useful genes is not difficult in a science laboratory.
Such modifications are already being applied commercially for food crops. In the USA, modified maize, soybeans, tomatoes and cotton are growing on farms with the objective of reducing the cost of production by limiting the amount of chemicals applied to control weeds and pests; and in the Andes potatoes with a fish gene for frost-resistance are being field-tested. The action of the gene which controls ripening is being reversed to extend shelf-life of fruit. For gardeners, it may be necessary to modify plants to withstand climate changes if global warming is occurring.
The discussion focussed on the genetic modification of food crops by Monsanto with most of the audience opposed to the procedure until more knowledge of the side-effects is obtained. The speaker was more relaxed about the procedure and felt that, in any case, it was now probably unstoppable.
Don Lovell
(The method of extracting DNA in the kitchen is explained in
“DNA Your Onions?” a copy of which can be supplied by the Editor).