Emmanuel Macron has been accused of sending the daughter of a farmer to the “slaughter” after choosing the politician to square off against Marine Le Pen’s populist poster boy in the EU elections.

Valérie Hayer, 37, head of the centrist Renew Europe group in the European Parliament – the chamber’s third-largest – will reportedly take on Jordan Bardella, 28, of the National Rally party in the June vote.

Mr Macron is said to have been won over by the fact that she is, in her own words, a farmer’s “daughter, granddaughter, sister and sister-in-law”. She was brought up on a farm in Saint-Denis-d’Anjou in the Loire area.

“They’re appointing an unknown, it’s a bet. But she has proved her worth at the European Parliament,” said one government aide.

Mr Macron was booed during an appearance at the annual Paris Farm Show this weekend.

During the event, furious farmers clashed with riot police and broke stands.

Arnaud Rousseau, chairman of the National Farmers’ Union, said: “I’ve been coming to the show for 25 years and I’ve never seen anything like it. It was total chaos.”

Ms Hayer was not Macron’s first choice as EU election campaign leader. At least three men, including Jean-Yves Le Drian, ex-defence minister, and Bruno Le Maire, current finance minister, reportedly turned the post down. The previous favourite, Stéphane Séjourné, became foreign minister in a recent reshuffle.

Mr Macron spurned Clément Beaune, his erstwhile anti-Brexit pitbull who has fallen from favour, and ruled out Thierry Breton, internal market commissioner, according to Le Monde.

Some question whether a little-known politician as Ms Hayer stands a chance against the high-profile Mr Bardella. In a WhatsApp group among Macron aides seen by Le Monde, one fretted: “The men all said no. They send a woman to the slaughter. It’s a hospital pass.”

During the Paris farm show, the French president cut the ribbon to chants of “Macron, resign” but eventually managed to partially win over union leaders in a no-holds-barred discussion by promising more concessions just weeks after tractors laid siege to Paris in protest.

His government had already unveiled a €1.2 billion package to appease farmers complaining of falling revenues, environmental constraints and red tape less than a month ago.

However, Mr Bardella, widely seen as a future head of state in an increasingly Right-wing country, received a hero’s welcome from many farmers who vented their despair over financial difficulties and stifling EU norms, along with “unfair” foreign competition.

His National Rally party, RN, is polling to comfortably beat Mr Macron’s Renaissance group in the June European elections. That may change, the Macron camp hopes, now that it has belatedly named its leader – the last to be announced.

EU agriculture promises to be a key issue in the upcoming ballot amid farmer protests in several countries.

Nathalie Loiseau, France’s former, ill-fated, Europe minister, described Ms Hayer’s nomination as “excellent news”.

“A competent and courageous young woman is our campaign leader,” she said.

“It was about time someone was appointed and we started campaigning. We have work to do,” one Macron loyalist told Le Parisien.

The French president is reportedly banking on his prime minister Gabriel Attal to lend his support to Ms Hayer. He dispatched the 34-year-old government chief to the farm fair in a last-minute surprise visit on Sunday night to steal Mr Bardella’s thunder.

A poll in Le Parisien on Monday suggested Mr Attal and Mr Bardella are almost neck and neck in popularity ratings among 18-to-24-year-olds on 32 to 35 per cent support, respectively.

Mr Macron clearly also intends to wade into the campaign.

In an interview with Le Figaro out on Monday, he accused militant farmers’ union Coordination Rurale of having direct links with Ms Le Pen and acting as her henchmen. He also said voting for Mr Bardella could lead to a de facto Frexit and the end of public accounts committee subsidies, which amount to around €9 billion per year for France.

On Sunday, Mr Bardella denied his supporters were behind violence at the farm fair, describing the head of state as a “schizophrenic conspiracy theorist who is worryingly paranoid”.

Ms Hayer is due to officially launch the European campaign for Mr Macron’s Renaissance group in Lille on March 9.