Ukrainian tractors lead race for Orange Prize Debut novelist leads the race for Orange Prize

A debut novel which was initially stacked in the agricultural section at book shops has struggled out of obscurity to lead the race for the Orange Prize.

A Short History of Tractors in Ukrainian by Marina Lewycka, which charts the dreams of an eccentric elderly man living in Britain, is one of the six novels on the shortlist for the £30,000 prize.

The daughter of Ukrainian immigrants, Lewycka, in her late fifties, struggled to have her first novel published. It was finally spotted by an external examiner on her creative writing course, who also happened to be a literary agent.

Fellow nominee Joolz Denby, 49, a former biker and mother of 12, drew on her experiences in the Satan's Slaves biker gang for her novel, Billie Morgan.

Kate Mosse, co-founder of the prize, said: "The list shows a trend towards people who have had experiences, who have lived their lives and come to writing late. These are not coming-of-age novelists. It is in some ways the triumphing of experience over youth. That said, we do not select on age and the judges often do not know the age of the authors."

The list also features the established author Lionel Shriver, selected for her seventh novel, We Need to Talk About Kevin, about a high school student who kills seven of his fellow students. Jane Gardam, the only author to have won the Whitbread Novel of the Year twice, was selected for her novel, Old Filth, which charts the life of a barrister called Filth (a nickname which stands for Failed in London Try Hong Kong), from his birth in what was then Malaya to old age.

Maile Meloy, in her early thirties, is the youngest on the list and was selected for her first novel, Liars and Saints, and Sheri Holman, in her late thirties, was selected for The Mammoth Cheese, her third novel.

This is the first year the list has comprised only British and American authors, and will delight the small independent publisher, Serpent's Tail, which published bothBillie Morgan andWe Need to Talk About Kevin.

The Orange Prize, for female authors writing in the English language, is in its 10th year. Last year's winner was Andrea Levy, who became the first author to win the Whitbread and Orange prizes in the same year, for Small Island.

The winner will be announced on 7 June in London. Broadcaster Jenni Murray, the chairwoman of the judges, said: "I'm delighted with this shortlist. There's a broad range of subject matter, three American and three British writers, new writers, established writers and a quite astonishing array of titles. Now comes the really tough job of choosing one from such an inspiring group."

The shortlist

JOOLZ DENBY: Billie Morgan (Serpent's Tail)

Billie is in her forties, running a jewellery shop in Bradford, trying to forget the past. But Billie was a hardcore biker chick, one of the Devil's Own, and involved in murder. Now, years later, she has to face the consequences.

JANE GARDAM: Old Filth (Chatto & Windus)

Filth was an international lawyer with a practice in the Far East. Now, only the oldest QCs can remember that his nickname stood for Failed In London Try Hong Kong. His story is traced, from his birth in Malaya through to old age.

SHERI HOLMAN: The Mammoth Cheese, (Virago)

When Manda Frank gives birth to 11 babies, the world descends on her town. Meanwhile, cheesemaker Margaret Prickett decides to make a point but fails to notice her daughter's plight.

MARINA LEWYCKA: A Short History of Tractors in Ukrainian, (Viking)

When their widowed father in Peterborough announces he's to remarry, sisters Vera and Nadezhda decide to save him from the Ukrainian gold-digger. But he wants to follow his dreams.

MAILE MELOY: Liars and Saints (John Murray)

Yvette Santerre, whose husband is away at war, meets a man while visiting the beach with her children. The chequered history of the Santerre family, with its ugly secrets, is told in a cross-country car trip.

LIONEL SHRIVER: We Need to Talk About Kevin (Serpent's Tail)

Kevin Katchadourian kills seven of his fellow high-school students, a cafeteria worker and a teacher. While visiting him in prison, his motherwrites to her estranged husband about Kevin's upbringing.