TWO former students who first met in a lecture theatre just weeks after Second World War broke out are staking a claim to be the country's oldest graduate couple.

Ian and Katharyn Callan, who first shared botany classes at Edinburgh University in October 1939, celebrate 70 years of marriage today.

Mr Callan recalled: "By April 1940, our friendship had developed into love and we became unofficially engaged. I say unofficially because our parents thought we were too young and my father took the view that war-time marriages never last."

The couple, who now live in the village of Llanybdder, Monmouthshire, have five children, seven grandchildren and four great-grandchildren.

Both Mr and Mrs Callan graduated with first class honours degrees in botany and they can also reflect on significant successes in their professional lives. Mrs Callan (nee Shaw), 94, who is originally from Birkenhead, was part of a small team of scientists that developed the anti-malarial drug paludrine during the Second World War.

Mr Callan, 95, a native of Prestwich, North Manchester, specialised in crop protection – particularly cotton and rice – and worked extensively in Africa and the Far East.

In retirement, their shared love of botany inspired them to create a hay meadow at Dolau Hafod a Winllan in Ceredigion, mid-west Wales. The six-acre wildlife garden, declared a Site of Special Scientific Interest, was open to the public under the National Gardens Scheme.

Mrs Callan says the secret of long life is moderation in everything and she believes a successful marriage is built on "tolerance and give and take".

Mr Callan said: "We had a wonderful time as students at Edinburgh during the war and have so many happy memories of our time there."