Method for placing a cutting in a plug

The present invention relates to a method for growing a plant comprising obtaining a cutting by dividing tissue material in vitro, placing said cutting into an opening of a microtray provided with openings, packaging and dispatching these microtrays with cuttings.

Such a method is generally known in the prior art. hi the process of growing plants, obtaining cuttings from a mother plant is a particularly costly step. To date, it has not been possible to produce cuttings in a reliable mechanical way, so that the entire operation still has to be carried out by hand. For this reason, this activity is carried out as much as possible in low-wage countries.

However, growing the plant can to a large degree be carried out mechanically and can therefore take place in countries which have an optimum climate and/or are close to the consumer market. This means that the cuttings have to be transported over a considerable distance. Many countries have import and export regulations in place, which add to the problems encountered when trying to transport the cuttings under optimum conditions. Depending on the plant, this will result in relatively many or relatively few problems. The present invention in particular relates to cuttings from gerberas and bromelias, but it will be understood that other plants can also be treated with the invention described below.

When obtaining cuttings, a distinction has to be made between obtaining in-vitro material and in-vivo material. In the latter case, for example, the tips of plants are cut off and used as material for cuttings. However, the present invention relates to the treatment of tissue-growing material, in which precursors of plants, such as leaves which generally do not yet have a protective wax layer and which are grown under laboratory conditions, are created from a number of plant cells. The leaves are separated from the tissue material under laboratory conditions.

A method of this type is known from NL 1019738. With this method, cuttings,

optionally with or without a root, are placed in a substrate and this substrate is sealed with a film and subsequently the substrate is handled further.

NL 6811177 B discloses the use of foam material for storing plants therein.

It is an object of the present invention to facilitate handling of the cuttings obtained in this manner, while in addition preventing duties at the border as much as possible as well as formalities at the border, so that transport can be carried out as quickly as possible. In addition, it is an object to optimize the conditions inside the packaging to such an extent that the cuttings can be transported for a considerable time, thus reducing the costs of transportation. In addition, the sterility, if present, has to be maintained at all times.

This object is achieved with a method described above in that, upon receipt of said microtray, a series of cuttings are taken out of the microtray simultaneously and are simultaneously placed in a series of plugs and, after having been placed in a plug, the cutting with plug is kept for at least one week in a space having a relative humidity of more than 85%.

According to the present invention, the cuttings obtained in vitro are arranged in microtrays provided with openings and subsequently transported over a great distance. During placement and transportation, no root growth occurs, so that, if any borders are crossed, there are no financial or formal impediments relating to cuttings having roots. As a result, it is possible to achieve significant cost savings. It has been found that if cuttings can be treated in such a way, the transport time can be significant. Even at the destination, there are still no roots present and during the separation, i.e. the removal of these cuttings from the packaging, the cuttings still have no roots.

The cuttings are subsequently placed in plugs which are optionally provided with an opening which may have been made earlier. Thereafter, the plugs with the cuttings are taken to a climate control chamber or the like with a well-defined humidity. Preferably, this humidity is at least 85% and more particularly 90-99%. In any case, this humidity has to be such that no condensation forms on the plants. On the other hand, a high

humidity has been found to be essential to achieve successful formation of roots. The minimum residence time in such a climate chamber under such conditions is at least one week and preferably approximately 2 or 3 weeks. During this time, it is preferable if there is some ventilation, so that the leaves are subjected to a slight wind pressure. This has proved to stimulate the development of the plant particularly well. The plugs are preferably arranged in a tray. During the time in the climate chamber, preferably no protection is provided around the plugs, i.e. there is no film or the like present as in the prior art. In addition, it is possible to arrange a large number of plugs in the climate chamber spaced apart in the vertical direction. As a result, it is possible to achieve an extremely high plant density. The development of the cutting can be stimulated by means of artificial light. According to a particular embodiment of the invention, the transfer of the cuttings from the microtrays to the plugs preferably takes place mechanically. Of course, it is also possible to transfer the cuttings to pots, each pot receiving one or more cuttings. Following the treatment in the climate chamber, the trays may be sent to, for example, growers. The trays are preferably stacked, spaced apart by corner pieces.

In order to facilitate handling of the microtrays, two microtray sections, each comprising a row of openings, are attached to one another while the cuttings are being introduced into the microtrays and during transportation thereof. By providing adjacent microtray sections with bridges, it is possible to carry out a simple breaking operation only at a later stage, such as during the removal of the cuttings from the microtrays.

The microtrays or microtray sections, respectively, preferably consist of a foam material, such as a plastic foam material, and in particular of a polystyrene material, hi addition, according to an advantageous embodiment of the invention, a microtray or microtray section, respectively, is provided with a body, in which through-openings are provided for the cuttings, and a spacer in order to place this body at a distance from a support. According to a particular embodiment of the invention, a microtray obtained in this manner can be placed in a food gel or the like in a simple manner. The gel contacts the through-openings in the microtray and in this manner the separated parts are able to already develop during transport.

According to a further particular embodiment of the invention, the microtrays are placed next to one another in a closable container, such as a box, when the cuttings have been introduced.

As each in each microtray contains a series of cuttings, the cuttings are thus placed in the box series by series.

This container can be completely closed from the environment. Such a closure can, moreover, be obtained by sealing, for example using the flow-pack method. Surprisingly, it has been found that if the volume of the container in relation to the number of microtrays is conveniently chosen, the microtrays can remain in the container for a relatively long time without any problems occurring. It is possible, particularly by the moistureproof closure, to prevent deterioration in the quality of the cuttings. If desired, it is possible to arrange in the box a tissue or the like which is moistened before the box is closed and which releases moisture during transport In addition to moisture, such a tissue may contain a disinfectant and fungicide and other substances.

According to the present invention, the microtrays are arranged in the box in a layer, i.e. the microtrays are not stacked on top of one another, but arranged next to one another.

In order to facilitate the removal of the microtrays from the box or other container, a removal film/foil may in addition be present. This is preferably provided under the microtrays in the box or other container and by lifting up the removal film/foil all microtrays are removed from the container at the same time.

With the method according to the invention, the cuttings do not require feeding until the moment when they are placed into the plugs. This results in a considerable saving in material (such as a nutrient medium). By placing the cuttings in microtrays in an "organized" manner, it is possible to remove the cuttings from the microtrays in a simple manner at a later stage by mechanical means and place them in the trays.

As a result of the openings extending at right angles to the microtrays and being arranged in the latter, the cuttings are unambiguously positioned in an upright position. This makes it possible to move the cuttings in a simple manner by mechanical means at a later stage. If desired, a sorting operation may be carried out when the cuttings are placed in the microtrays as well as when they are removed therefrom. Such a sorting operation may be carried out on the basis of quality, size, and the like.

When the microtrays are filled, the exact number of cuttings per box or other container is known.

The invention also relates to a microtray as described above. Also, the invention relates to an assembly consisting of two microtray sections attached to one another as well as a container with a single layer of microtrays arranged therein. The invention also relates to an outer packaging consisting of a number of containers in which in each case one single layer of microtrays with cuttings is arranged.

The invention will be explained in more detail below with reference to an exemplary embodiment illustrated in the drawing, in which: fig. 1 shows how cuttings are obtained; fig. 2 shows how a microtray is provided; fig. 3 shows how the cutting is placed in the microtrays; fig. 4 shows a box for packaging the cuttings; fig. 5 shows how the cuttings are packed inside the box; fig. 6 shows how the box is closed; fig. 7 shows how the boxes are placed in an outer packaging; fig. 8 shows how the microtray is divided into microtray sections; fig. 9 shows how the cuttings are removed from the microtrays; fig. 10 shows how the cuttings are placed in plant plugs; fig. 11 shows how trays are transported to a climate chamber; and fig. 12 shows a variant of a microtray.

In fig. 1, reference numeral 1 denotes a mother plant from which a number of cuttings are obtained by means of a cutting operation using manual force and great skill on

developing cell tissue (in-vitro cultivation). Preferably, such a labor-intensive operation is carried out in low-wage countries and always in a sterile environment.

Fig. 2 shows a microtray 3 consisting of microtray sections 4 which are attached at their ends by bridges 5. Each microtray (microtray section) is provided with a series of openings 6. These are through-openings with a preferably cylindrical shape. When the cuttings or tissue shoots 3 have been obtained, these are placed in the microtray sections 4, as shown in fig. 3.

Fig. 4 shows a box 9 provided with a container part 11 and a Hd part 10. A removal film/foil 12 is arranged in the box and a tissue 13 is also provided. Tissue 13 contains moisture and fungicidal/disinfectant material to ensure the sterility of the cuttings as much as possible, as the operation of separating the cuttings 3 from the mother plant was carried out under sterile conditions.

Fig. 5 shows how a series of microtrays 3 are placed in a box 9. These microtrays 3 are arranged in the box in a single layer, following which the box is closed using the Hd 10. This closure is essentially sealed with respect to the environment. A number of boxes 9 are, as is illustrated diagrammatically in fig. 7, arranged in an outer packaging 14, such as a further box and more particularly a cardboard box. The cuttings are then ready to be transported. According to the present invention, the conditions in the box 9 are optimized to such an extent that this transport may last at least one week and optionally several weeks without leading to permanent damage to the cuttings. No root development takes place during this transport, as there is no nutrient medium present for the cuttings. Surprisingly, it has been found that the quality of the cuttings is not adversely affected during this transport.

Fig. 8 shows how, at the destination, the microtray sections 4 are separated at the bridges 5. This separation is indicated by means of arrow 16. Subsequently, each microtray section 4 is placed under a handling device 18 consisting of a number of grippers 23, as described in Netherlands patent 1,030,277 in the name of the JHL Group. This makes it possible to grip a number of cuttings 5 simultaneously in a considerate manner. These are then moved above a tray 19 in which a number of plant

plugs 20 are arranged. During this move, the distance between the cuttings is increased. The final situation is shown in fig. 10, where both cuttings 2 have been introduced into the plugs 20. The plugs may be provided with an opening which facilitates introduction. In addition, it is possible to dip the cuttings in a medium which stimulates root growth before they are placed in the plugs 20.

When the trays 19 have been filled, they are taken to a climate chamber with high humidity, such as more than approximately 85%, and more particularly approximately 95% and are exposed to an optimum climate and lighting for at least one week, and preferably for several weeks. It has been found that root development occurs after one or two weeks.

According to the present invention, the formation of roots only takes place at the destination and not immediately after the cuttings have been cut. During the time between obtaining the cuttings and arrival at the destination, on the one hand, root formation is prevented as much as possible, but, on the other hand, measures are taken such that the quality of the cuttings does not deteriorate. Surprisingly, it has been found that this can be achieved by means of the measures described above.

As is evident from fig. H, trays are packaged, after having been removed from the climate chamber, spaced apart with the interposition of a corner piece 22 and sent to growers. There, the plants provided with roots can grow in a greenhouse, for example, to become the corresponding (pot) plant.

Fig. 12 shows a variant of the microtray which is provided with openings 6, just like the previous embodiment. The tray consists of a tray body 34 and a spacer 35 provided underneath at the ends thereof. As a result, the tray body 34 will be at a distance from the bottom during use. By filling the space in which the tray is placed (small box) with a nutrient medium, such as agar gel 36, this medium will be under the open bottom of the openings 6 when the tray is placed in the nutrient medium. This results in nutrient medium becoming available to the cutting introduced into the openings 6 and all development thereof can take place during transport, for example root development

Upon reading the above description, those skilled in the art will immediately be able to think of variants. Various steps and/or packagings may be executed differently without departing from the scope of the present invention.

In addition, exclusive rights are sought for the measures described in the subclaims, independent of what has been described in the main claim.