**3.2 Methods of distant graft**

There have been many different graft methods developed from the long-term graft practices. According to the resource of scion, the graft methods can be classified into three categories: bud graft, branch graft and stem graft. But according to the grafting modes of stock and scion, the graft methods can be divided into three main categories: plug graft, cleft graft and splice graft. For plug graft, the lower or upper of stem of rootstock seedlings is made a hole by using of bamboo sticks, where the scion is inserted after its stem end is whittled into wedge shape, so that the rootstock and scion can develop a new plant; cleft grafting is that the scion with wedge-shaped end is inserted the spliced mouth of the stem of rootstock; As for splice graft, all the stems of rootstock and scion are cut into the inclined planes with the same angle and length, and then they are bounded together. Other graft methods such as whip and tongue graft, saddle graft, bridge graft, inarch graft etc. are sometimes used in practices. In addition, according to the combination pattern of rootstock and scion, the graft methods are including single Shoot to root grafts, Y shaped grafts with one scion, interstock grafts, Y shaped grafts with two scions, Y shaped grafts with Y shaped shoots and A shaped grafts with two rootstocks (Jia and Han, 2010).
