And the ‘plant of the year award’ goes to….. Thale Cress (Arabidopsis thaliana)
You don’t have to go up into the Dales or visit a nature reserve to find interesting plants. Just keep your eyes open when you next go into town. There is a rich flora to be found growing in the cracks in the pavement and waste ground, all with their own interesting stories. One of my favourites, and I think worthy of a ‘plant Oscar, BAFTA or Nobel Prize’, is Thale Cress (Arabidopsis thaliana). This small and insignificant plant belongs to the cabbage family and has been the cornerstone of plant research, being used to study plant genetics, physiology, evolution, population biology and has even played its part in space travel. For those of you who have studied biology at A-level or degree level you may recall the common fruit fly (Drosophila melanogaster) which has similarly been used for the study of animal genetics.
Many of you will remember the fanfare in June 2000 with the widely covered news that the draft version of the human genome had been completed. The full publication in the scientific journal Nature took place in 2003.
Almost slipping by unnoticed, six months later in December 2000, was the publication of the complete gene sequence of Thale Cress, the first flowering plant to have its genome sequenced.
Thale Cress was an ideal plant to choose, having just five short chromosomes. The amount of genetic material in Thale Cress is just 0.004% of that found in the human genome. This makes it ideal for studying plant genetics.
It is 56 years since we celebrated man first walking on the Moon (16th July 1969). Again, almost unnoticed in 1997 on the Mir space station, Thale Cress became the first flowering plant to complete its complete life cycle in space i.e. germinating from seed, growing, flowering, fertilisation taking place, and then setting seed.
Again, it was an ideal choice, having both a very short life cycle of just six weeks and self-pollinating i.e. not requiring insect or wind vectors.
Thale Cress’s short life cycle, combined with its long flowering period, allows multiple generations in any one year. This, with the production of a large number of viable seeds, makes it a very successful weed. One last reason why I like Thale Cress, is that it was first described by a fellow medical doctor Johannes Thal in 1577, with Carl Linnaeus giving the plant its specific Latin name in his honour – ‘thaliana’. Next time you are out shopping, keep your eyes open; you will be surprised what you might find in the local supermarket car park. Only last year David and Joan Alred found the parasitic plant Ivy Broomrape growing in a planter next to the outdoor seating in Otley Waitrose.