GARDENINGAS WE approach primrose season — complete with delicate blooms and entrancing perfume — Thompson & Morgan has released details of an intriguing primula back-story of Darwinian significance.
Research involving primula seed from a packet purchased from the 1995 T&M catalogue has resulted in the identification of a cluster of genes responsible for reproductive characteristics in flowers noted by Charles Darwin more than 150 years ago.
Darwin noticed some plant species with two distinct forms of flower, where male and female reproductive organs were of differing lengths, had evolved that way to promote 'out-crossing’ by insect pollinators.
'Out-crossing’ is the process by which plants are pollinated from pollen from a different plant of the same species.
The process of 'out-crossing’ means that genetic diversity is increased, which reduces the possibility of the plant being subject to disease or genetic abnormalities.
Prof Phil Gilmartin, of the School of Biological Sciences at the University of East Anglia (UEA), has been involved in the research of heterostyly — the term given to Darwin’s insight into the significance of the two distinct forms of flower — for a large part of his career.
His team has recently announced a major scientific breakthrough. They have identified exactly which part of these species’ genetic code made them that way.
He said: "This study answers some of the crucial questions that have been asked since Darwin’s time and for me since I bought my first packet of Primula seeds 20 years ago."
Prof Gilmartin tweeted T&M to say his discovery had all started with a packet of primula seeds bought from the seed merchants’ 1995 catalogue — and he added a photo of the catalogue’s now worn front cover.
In a conversation with Prof Gilmartin, it was established the variety in question was primula blue jeans.
He said the choice of this particular F1 hybrid primula variety was pivotal as it gave a very homogenous (similar) parent line on which to base his research.
Researchers mapped the plant’s genes and sequenced the primula genome to find the specific gene cluster responsible for creating the differing flower forms.
Prof Gilmartin said this insight has profound implications for our understanding of a key evolutionary innovation of flowering plants.
The research — and discoveries such as this latest breakthrough — by scientists, such as the UEA team, are considered to be vital to understanding the mechanism of pollination.
Prof Gilmartin said: "The more we understand the genetics which underpin the development of flowers and the reproduction of different species, the more we can discover about the entire system of pollination, which in turn strengthens our understanding of biodiversity and food security — both topical issues.
"With challenges, such as climate change and its effects on plants, crops and their insect pollinators, it’s even more important to understand the pollination mechanisms and how species can and will react."
l T&M appears to no longer have this beauty in its catalogue and I have been unable to find it anywhere. If any reader knows a source I will happily pass it on in my column.
That information and any other gardening tips and tales can be sent to me at, 522210 or at the County Press, Brannon House, 123 Pyle Street, Newport PO30 1ST.