Oops I did not see my original post on the same subject.

Growing most types of fruit from seed is generally a bad idea. There is a high chance the fruit will not be as good as the parent variety. For those of you who are not aware of how this works, in nature fruit species can have a lot of genetic diversity from generation to generation. When a good producing tree is found, it then gets propagated from cuttings. People usually do not want to take the trouble of growing a fruit tree from seed when they do not even know whether the fruit will be good. Generally though, lemons produce truer to seed than oranges do. Not talking about citrus here, but for fruit trees in general, it is theoretically possible to breed fruit that produces truer to seed, but it takes many more generations of breeding. These are often traditional heirloom varieties that have been around a long time. Whereas the seed from a Navel orange will not really result in a Navel variety, some of these heirloom varieties can essentially be continually propagated from seed. The terms "heirloom", "true to seed", and fruit "variety" can all be very relative and ambiguous terms.

Rooting a meyer lemon cutting would work under a misting system. It is a lot of work and the success rate might not be as high as grafting the cutting onto another citrus seedling. The fruit from a cutting would be the same as the fruit from the tree you got the cutting from. I recommend grafting over rooting a cutting because it's easier and the grafted plant will already have a good root system and it wont have to develop one.

It looks to be right on the graft line. Your Meyer could be on a lemon rootstock. Better safe than sorry? How fast does the shoots grow relative to the main top?