NUTRIENT MEDIUM FOR AUTOMATED CULTIVATION OF PLANTS

Abstract

A nutrient medium for the cultivation of plants, containing (a) 3 g/l to 18 g/l agar and (b) 0.5 g/l to 3 g/l carrageenan, as well as plant plugs which contain such a nutrient medium, a method for the production of the plant plugs, and a method for the automated or semi-automated cultivation of plants using the plant plugs.

Claims

1. A growth medium for the cultivation of plants, the growth medium comprising: (a) 3 g/l to 18 g/l agar; and (b) 0.5 g/l to 3 g/l carrageenan.

2. The growth medium as claimed in claim 1, further comprising: (c) a shape-stabilizing component.

3. The growth medium as claimed in claim 2, wherein the shape-stabilizing component is a water-insoluble component.

4. The growth medium as claimed in claim 3, wherein the water-insoluble component is selected from the group consisting of plant parts, plastics, minerals, and mixtures thereof, and materials produced therefrom.

5. The growth medium as claimed in claim 4, wherein the plant parts are jute, hemp, flax, and/or coconut fibers.

6. The growth medium as claimed in claim 4, wherein the plastic is polyurethane foam.

7. The growth medium as claimed in claim 2, wherein the shape-stabilizing component is a water-soluble component.

8. The growth medium as claimed in claim 1, comprising agar in a concentration of from 5 g/l to 12 g/l.

9. The growth medium as claimed in claim 1, comprising carrageenan in a concentration of from 1 g/l to 2.2 g/l.

10. The growth medium as claimed in claim 1, wherein the growth medium has a gel strength of from 400 to 1200 g/cm.sup.2.

11. A plant plug for the cultivation of plants, preferably for the automated or semiautomated cultivation of plants, wherein the plant plug comprises a growth medium comprising: (a) 3 g/l to 18 g/l agar; and (b) 0.5 g/l to 3 g/l carrageenan.

12. The plant plug as claimed in claim 11, wherein the plant plug has a volume of from 2 cm.sup.2 to 20 cm.sup.2.

13. The plant plug as claimed in claim 12, wherein the growth medium in the plant plug comprises a water-insoluble component and an outer volume of the plant plug is reduced by less than 60% in the case of a dissolution and removal of the agar and carrageenan owing to a stabilizing action of the water-insoluble component.

14. A method for producing a plant plug, preferably a plant plug for the automated or semiautomated cultivation of plants, comprising (a) providing a growth medium in a liquid state; and (b) gelling the growth medium in the shape of a plant plug.

15. A method for the automated or semiautomated cultivation of plants, comprising (i) contacting a plant plug with a plant or a plant part; (ii) cultivating the plant plug and plant or plant part together under growth conditions suitable for the plant such that the plant or the plant part roots in the plant plug and a plant unit is formed by plant or plant part and plant plug; and (iii) the plant unit is transferred in an automated manner into (iii.1) a recess in a larger plant plug; (iii.2) a cell in a cultivation tray; and/or (iii.3) a soil substrate.

16. The growth medium as claimed in claim 2, wherein the shape-stabilizing component is a water-soluble component selected from the group consisting of gelatin and hydroxyalkylcellulose.

17. The method for producing a plant plug as claimed in claim 14, wherein the growth medium comprises: (a) 3 g/l to 18 g/l agar; and (b) 0.5 g/l to 3 g/l carrageenan.

18. The method for producing a plant plug as claimed in claim 14, further comprising: (c) sterilizing the growth medium.

19. The method for the automated or semiautomated cultivation of plants as claimed in claim 15, wherein the plant plug comprises a growth medium comprising: (a) 3 g/l to 18 g/l agar; and (b) 0.5 g/l to 3 g/l carrageenan.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0078] Exemplary embodiments of the invention are depicted schematically in the drawings, where:

[0079] FIG. 1 shows various embodiments of the plant plug (12) according to the invention that together with a shoot (10) forms a plant unit (8), wherein the plant plug (12) has a cylindrical (A), cuboidal (B) or hemispheric (C) shape. In the embodiment shown in FIG. 1(A), a plant slit (16) was introduced into the plant plug (12), into which the shoot (10) was inserted. The shoots (10) in FIGS. 1(B) and (C) were gently pushed into the surface of the plant plug (12).

[0080] FIG. 2 shows the plant units (8) as per FIG. 1, wherein the shoot (10) has formed a root system (14) in the respective plant plugs (12).

[0081] FIG. 3 shows the automatic transfer of a rooted plant unit (8) according to the invention (cf. FIG. 3(A)), wherein the plant unit (8) was inserted by means of a gripper (20) into a recess into a larger plant plug that is not according to the invention, wherein the larger plant plug consists of a soil substrate (18) (cf. FIG. 3(B)). The gripper (20) comprises a gripper head (22) having two blades or lances, wherein, as a result of piercing of the blades or lances into the plant plug (12), a sufficiently good connection between gripper (20) and plant plug (12) is created for the plant unit (8) to be able to be transported by means of the plant plug.

[0082] FIG. 4 shows a plant block (24) according to the invention consisting of 48 plant units (8) as per FIG. 1(B).

[0083] FIG. 5 shows examples of plant plugs according to the invention without a shape-stabilizing component containing rooted Amelanchier (Chuckley pears);

[0084] FIG. 6 shows examples of plant plugs according to the invention without a shape-stabilizing component containing rooted Auricula (primula);

[0085] FIG. 7 shows examples of plant plugs according to the invention with the polyurethane foam BVB Sublime as shape-stabilizing component containing rooted Echinacea (coneflowers);

[0086] FIG. 8 shows examples of plant plugs according to the invention with the polyurethane foam Oasis as shape-stabilizing component containing rooted Leontopodium (edelweiss); and

[0087] FIG. 9 shows examples of plant plugs according to the invention with polyurethane foam and coconut fibers as shape-stabilizing components containing rooted Heuchera (coral bells).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0088] Further advantages, characteristics and features of the present invention become clear in the following detailed description of exemplary embodiments on the basis of the appended drawings. However, the invention is not limited to said exemplary embodiments.

EXAMPLES

Example 1: Production of a Plant Plug Using Luffa as Shape-Stabilizing Component

[0089] Technical Conditions for Producing a Plant Plug According to the Invention

[0090] The individual chemical components (macro-, micro-, vitamin components) were dissolved in distilled water and topped up to 75% of the amount to be boiled. Lastly, sugar and phytohormones were appropriately added. Appropriate concentration data for the different chemical components were gathered from the relevant literature (George, Edwin F., Puttock, David J. M., George, Heather J., 1987, Plant Culture Media, Volume I: Formulations and Uses, ISBN 0-9509325-2-3-Vol1, Exegetics Ltd., Edington, Westbury, Wilts. BA 13 4QG, England).

[0091] Then, the amount to be boiled was topped up to 100%. Thereafter, the pH was adjusted by dropwise addition of 1 N NaOH solution while stirring the growth medium. Finally, the appropriate concentration of gelling agents was added (6.4 g/l agar, CERO Agar Agar Powder, type 8925 X; 1.6 g/l carrageenan, CEROGEL Carrageenan (Danish agar agar), type 8886, 100% refined kappa-carrageenan). Either it was possible for the growth medium formulation to be filled into trays that were still nonsterile at this point for autoclaving (121 C., 15 min), or what was first carried out was steam pressure sterilization (121 C., 15 min), microwave sterilization, irradiation or sterile-filtration under constant mixing, and filling into sterile trays at a clean bench after the sterilization; to this end, the medium was cooled to 50-60 C.

[0092] As water-insoluble, stabilizing additive, dried luffa fruit was cut into pieces, the pieces having the size of a plant plug. The luffa pieces were then placed into the trays to be filled before said trays were filled with the growth medium.

[0093] After cooling, it was possible for the sterile vessels comprising trays and the plant plugs to be overlaid with plants for growth.

[0094] Overlaying of the Plant Plug with Plants

[0095] In this step, the plants were laid onto the plant plug for further growth or for rooting, either manually at a sterile work bench after division and possible shortening of leaves, cut into shape using scalpel and tweezers, or by a machine according to set-pattern programming using laser cutting or other automated division.

[0096] Culture Conditions Up Until Further Processing of the Plant in the Plant Plug

[0097] After overlaying, the plants grew in vessels (tray comprising individual cells based on plant plugs) under constant conditions in an artificially air-conditioned cultivation room. Said constant conditions included a uniform temperature (+/1 C.), uniform lighting with defined light color, and uniform relative air humidity and regular air exchange.

[0098] Automatic Process for Transplanting the Plant Plug

[0099] The plant grew up to a (rooted) shoot in the plant plug in the culture room in accordance with the culture protocol. It was possible, then, for said plant to be automatically transplanted. Robotic processing was achieved by gripping the individual plant plug from above, at the side and/or by pushing up from below by means of a push-out mechanism. The grippers can be needles, sheets or other holders, and they can be made from different materials. The plant plug was then gripped together with the plant and put down into a new (larger) plant plug (e.g., nonsterile soil substrate) or an individual cell of a plant tray. This automatic transplantation process can proceed under either sterile or nonsterile conditions.

[0100] Further Processing of the Plant Plug in a Greenhouse

[0101] The described in vitro culture protocol ended with the adaptation of the plant in the plant plug to the nonsterile greenhouse conditions. In this step, the plant plug, consolidated with gelling agent and provided with a non-water-soluble component, together with the plant rooted into a soil-substrate plug.

Example 2: Production of Further Plant Plugs According to the Invention

[0102] Analogously to the method described in Example 1, further plant plugs, in which luffa was not used as shape-stabilizing component, were produced and tested. The following plant plugs were produced and were tested with the following plants:

TABLE-US-00001 Shape-stabilizing component Plant species Result shown in None Amelanchier FIG. 5 None Auricula FIG. 6 Polyurethane foam Echinacea FIG. 7 (BVB Sublime) Polyurethane foam Leontopodium FIG. 8 (Oasis) Polyurethane foam Heuchera FIG. 9 and coconut fibers

[0103] The polyurethane foams mentioned in the table were each used in concentrations of from 40% to 70% by weight, based on the plant plug; the coconut fibers were used in concentrations of from 5% to 15% by weight, based on the plant plug.

[0104] Good results (not shown) were also achieved using gelatin foam as shape-stabilizing component. What were added to an individual cell from in vitro trays were 4 mg/ml Gelatamp (Roeko) and 2 ml of liquid growth medium (cf. Example 1). The gelatin foam Gelatamp took up 0.8 ml of the liquid medium and the resultant plant plugs exhibited an adequate quality for automatic handling.

[0105] Although the present invention has been described in detail on the basis of exemplary embodiments, it is self-evident to a person skilled in the art that the invention is not limited to said exemplary embodiments, but that, on the contrary, modifications are possible such that individual features can be omitted or different combinations of the presented individual features can be realized, so long as there is no departure from the scope of protection of the appended claims. The present disclosure includes all combinations of the presented individual features.

LIST OF REFERENCE SIGNS

[0106] 8 Plant unit [0107] 10 Shoot [0108] 12 Plant plug [0109] 14 Root system [0110] 16 Plant slit [0111] 18 Soil substrate [0112] 20 Gripper [0113] 22 Gripper head [0114] 24 Plant block