You are hereGrafting method


 How to Graft Tomato

          Tomato seedlings are almost always grafted using ‘tube grafting’ method in commercial propagation. However, ‘approach grafting’ may be optional if growers do not have a good healing system.
 
Tube Grafting Method
          This grafting method is also called ‘Japanese Grafting Method’. Matching scion and rootstock hypocotyl (or epicotyl) size is required.  
Materials
·        Scion seedlings at a two-true-leaf stage. Target diameter of grafting site (hypocotyl or epicotyls) is 1.5 mm.
·        Rootstock seedlings at the same leaf stage. Target diameter of grafting site (hypocotyl or epicotyls) is 1.5 mm.
·        Razor blade works the best for this grafting method.
·        Grafting tubes. Size needs to be selected for matching seedlings.
Methods
1.      Cut rootstock under cotyledons in a 45 degree or sharper angle. Cutting rootstock above cotyledons requires cautionary consideration as axillary buds may grow out when vigorous rootstocks are used.
2.      Place one tube a half way down on top of the cut end of rootstock hypocotyl.
3.      Prepare the scion with matching hypocotyl width cut in the same angle at about 5-10 mm below the cotyledons.
4.      Insert the scion into the grafting tube so that cut surface aligns perfectly with that of rootstock.
5.      Mist regularly with water to prevent desiccation.
6.      Move the tray filled with grafted plants to proceed for healing up to 7 days. Please see the section of healing methods for more information.
7.      No need to take the tube off as it will fall off as stem grow.
Key for success
·        Selecting matching size of scion and rootstock is important in this grafting procedure.
·        Grafting clips should also be selected according to the size. Too big clips cannot hold the grafted union or too small clips gives too much pressure and may deform the union.  

 

 

Approach Grafting Method
          This technique can assure a high success rate, although the grafting speed is slower than the other two methods. Scion’s roots are cut after healing is complete, and therefore high success rate can be achieved even with unfavorable healing conditions. This grafting method also has some flexibility in terms of matching size of scion and rootstock. As the rootstock shoots will be completely removed, this is the method having the least chance of developing rootstock shoots in the field. 
Materials
·        Scion seedlings at a two or three-true leaf stage.
·        Rootstock seedlings at a two or three-true leaf stage.
·        Razor blade works the best for this grafting method.
·        Grafting clips. Size needs to be selected for matching seedlings. Alternatively lead tape can work well.
Methods
1.      Make a downward cut at a sharp angle (60 degree relative to the horizontal plane) half way across the rootstock hypocotyl.
2.      Make a upward cut at the same angle a half way across the scion hypocotyl.
3.      Hook the upward ‘tongue’ of rootstock hypocotyl with the downward ‘tongue’ of scion hypocotyl. Hold them together with a grafting clip or by wrapping with a short strip of lead tape.
4.      Plant them together in larger cell or container.
5.      After 7 days in healing, cut the rootstock shoot and scion roots off.
6.      Remove the clip or tape.

 

 

Other Grafting Methods
There are a couple of other grafting methods used for tomato, including pin-grafting method and cleft (v-shaped) grafting method.
 
Grafting with Robot
Semi-automated robots are available for tomato grafting. Growing uniform scion and rootstock so that their hypocotyls are almost the same in diameter is critical for better grafting success rate. See more information on our ‘Grafting Robots’ page.