It is "120 per cent fake", Yuan Longping, who held the record earlier by growing 19.4 tonnes of rice in 2011, was quoted as saying by the Hong Kong-based South China Morning Post.
"I introduced the intensification method to China myself. It could increase yields by 10 to 15 per cent in low-yield fields, but it's not possible for fields that are already producing relatively high yields," Yuan said .
"He (Indian farmer) said they had lots of rain and little sunshine last year, but high yields would be impossible without adequate sunshine," Yuan told official China News Service, according to the Post.
Yuan was reacting to Sumant Kumar's success story published by the British newspaper Guardian which carried a feature on the achievement of the young farmer from Nalanda district of Bihar last year by using a method called System of Rice Intensification (SRI).
Yuan said judging by photos, the harvested plants appeared short and couldn't possibly produce high yields.
"Good soil is the basis of high-yield rice," Yuan said, adding that the soil where Kumar farmed was apparently inferior in quality.
Yuan also questioned the way India verified Kumar's claim.
"How could the Indian government have confirmed the number after the harvesting was already done" he asked.
"If Kumar is able to repeat his success next year, I will be glad to examine the results in the field personally," Yuan said.