It is seen by many as a modern day practice – and has people who are both for it and against.
But a study has revealed that even 10,000 years ago, cavemen were growing ‘genetically-modified’ rice.
The research showed that the ancient humans selected different strains of the rice and mixed their genes to create an ideal version of the crop.
This led to higher yields and better cultivation.
The discovery was made after an analysis of the genomes of wild rice alongside two sub-species with different histories.
This showed that the lengths of stems was shortened by variants in a gene called SD1.
This is one of the most important genes in modern rice breeding over the last fifty years, said Dr Masanori Yamasaki whose findings are published in Proceedings of the National Academy of Sciences.
Over time the mutations in SD1 yielded rice with shorter stems, sturdier stalks and greater grain output.