I like this picture, but I am extremely skeptical about drawing numerical inferences based on this Wikipedia data: this is just a list of rice varieties that volunteers randomly added to a Wiki page (a few of whom apparently happened to be enthusiasts of Indian rices), not a comprehensive or robust international comparison of rice cultivars. I would be interested to see what the picture would look like if it used a more neutral list created by adopting uniform criteria for each country.

In particular, the rice around the world today originated in China; there are surely many more than 5 types from that massive and geographically diverse country.

Hello ! Yes, I wondered why China's rice variety list was so low. Will update this with a more accurate dataset. Also, if you know of any official rice databases/datasets/resources and could point me in that direction, it would be very helpful. Thank you for checking out my notebook. :)