Shalom Rabbi Bloomenstiel.
What is the status of a tree that is a product of grafting a branch with sweet fruits onto the trunk of a same species tree with fruits that are not sweet so that we get a healthy plant with sweet fruits?
Example : We have a healthy orange tree with fruits that are not sweet. On to the trunk of this tree we graft a branch from a tree that produces sweet orange. Is this permissible ?
Yes. The fruit and tree are permitted. Its just grafting and no cross breeding of species involve here .
How about grafting a good citron branch onto a citron tree that produces not so good citron. Is this cross breeding?
As long as they are the same species, it is permitted. It sounds here that the only difference is the quality of the fruit. If they are the same species and you are just trying to improve the quality of the fruit, then there is no problem.
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