Bleskensgraaf, The Netherlands, March 21, 2019

Breakthrough in automatic transplanting of tissue culture plants

The demand for plants from tissue culture increases strongly worldwide. However, manually transplanting of tissue plants is a high cost factor for young plant nurseries. A huge challenge to automate this process for TTA, whose core business is handling and selection of young plants!

The general method of delivering TC plants is in plastic bags or boxes, filled with a layer of growing media, typically in a gelly shape, often and hereafter called agar. The automatic planting procedure starts with providing the plants in a tray in order to be able to handle them with the machine. The size of the tray or the size of the cells may vary, but the agar is provided in cells which are separated or have a limited connection. The plants, raised from tissue culture or other means of propagation, are provided in the agar and may have shaped roots in the agar. In recent years, various laboratories have developed trays especially for tissue culture. The various cultivation systems with different sizes of trays and cells as well as various species of plants have now successfully been tested and validated on TTA equipment.

During the past years, TTA have evolved their MidiFlat transplanter to be able to transplant plants from Tissue Culture. Part of this evolution was to develop a special tray holder for exact positioning of the trays. Also the standard TTA plant gripper design has been adapted in order to pick up the delicate and young plant material. Various models are available like blades, 3 holders, 2 holders, etc. The pick & place unit accommodates a feature to hold up the gripper pin system upon picking up of the plants. This prevents the gripper feet from sliding down and losing plants to early because of gravity. Transplanting often works in combination with a pusher pin system from below, which assists during extraction of the plants from the tray. Since some plants have a very limited number of roots, the movement of extracting the plants from the tray is very sensitive. Some species need a lateral movement side along the row of the tray in order to separate the plants in the plant grippers from those which are still in the tray or to prevent the plants from being pulled out of the agar. The MidiFlat transplanter allows for this movement, right upon picking up from the tray or at a later moment. This opens up a larger window of possibilities to work with plant species which have more tangled leaves. Therefore the lateral movement of the plant grippers are a useful part of the total solution. Another special feature which has been activated is the option to push the plants down in the receiving plug right after transplanting into larger plugs with regular growing substrate. Usually, plugs being placed in bigger plugs like to come up after transplanting. With the additional rear sliding movement upon transplanting, this problem can be avoided, however for the behavior of the plugs no correction was available. TTA programed their MidiFlat in such a way that upon transplanting the possibility was made to push the plugs down another time. Generally, transplanting plants WITH the agar is different from transplanting the plants without the agar in such a way that when the agar joins the plants into the receiving plug, tray or pot, the plants have more time to develop a root system which is suitable for the regular growing substrate. During the transition time, the remaining water in the agar plug helps the plants to survive through the old rooting system of the plant.

A large number of plant species with various tray systems have now been successfully tested. As a result of this, labor costs have been considerably reduced and the transplant quality greatly improved. On top of this we did also adapt our FlexSorter for this system! An unique transplanter which combines transplanting and selection to 2 or 3 different gradings.

For more information about this press release, please contact Bram Verschoor at