A pumpkin weighing 752lbs (341kg) beat a US state record at the Tanana Valley State Fair last week.

Tanana Valley State Fair competition exhibit manager Vanessa Spencer said eight men carried the gigantic pumpkin onto a forklift, which lifted it to a weighing scale.

Fairbanks Daily News-Miner reported that David Iles, of North Pole, grew the record-breaking pumpkin in his greenhouse using a "top secret" system, combining hydroponics and aeroponics.

Hydroponics grows vegetables with water only, while aeroponics uses neither soil nor direct water, relying on almost 100 per cent greenhouse humidity.

The previous state record was a 707-pound (321kg) pumpkin entered at last year's Alaska State Fair.