Let me explain about Mikan breeding. Mikans are known to demonstrate a phenomenon called bud variation which is when a completely different variety suddenly grows on one branch of a large Mikan tree. In the past, to develop Mikans, people choose the better one from bud variation. Now,new breed varieties are developed by seed crossings.Kiyomi oranges are the mothers of many newly bred varieties.To increase the number of Mikans, farmers used grafting. There was a time when grafting techniques were highly valued.In the beginning, yuzu was used as a rootstock, but it was too energetic and its roots kept moving downward, sucking up moisture and nutrients, and the tree above grew too large. While searching for a rootstock to replace yuzu, it was discovered that Karatachi is the most suitable tree. The Karatachi has natural thorny prickles so it was often used as hedge plant around homes in the past. It was good for repelling thieves and burglars.se it has prickles. It is useful for burglar‐proof.