Carwyn Jones is the new minister

"It would be quite wrong to think this implies any criticism of her," he said. "It is just that Carwyn is the right person to do the job now.

She is the only assembly member to have received the official reprimand but was not forced to resign.

Criticism of the secretary has come from many quarters, including farmers, primarily because she has been vegetarian for 20 years.

Last month she was attacked for a comment in the assembly that farming's contribution to the Welsh economy was "close to zero".

I have a tremendous admiration for what Christine Gwyther has achieved

Rhodri Morgan

Besides former first secretary Alun Michael, Ms Gwyther is the first cabinet member to lose her job.

But Mr Morgan insisted her career in the front line of Welsh Labour was not an end.

"I have a tremendous admiration for what Christine Gwyther has achieved against the odds during the assembly's first 15 months in a very difficult agriculture and rural development portfolio," he said.

It is a tremendous honour and a huge responsibility

Carwyn Jones

"The time has now come for a change and I have decided to appoint to this post Carwyn Jones, who has done an excellent job since I appointed him as deputy secretary for agriculture, environment and local government five months ago."

The decision comes ahead of the Royal Welsh Show in Builth Wells which Mr Jones will now attend with the first secretary.

Ms Gwyther said: "Whilst I am naturally disappointed to be replaced, I wish my successor well in what is sometimes a difficult but often rewarding brief.

Rhodri Morgan: "Tremendous admiration"

"But I would also like to place on record my thanks to the National Assembly staff who worked so assiduously over the past 15 months. They have been an absolute pleasure to work with."

Mr Jones, AM for Bridgend, said: "I am absolutely thrilled and delighted to be appointed by Rhodri Morgan as the cabinet member for agriculture and rural development.

"It is a tremendous honour and a huge responsibility."