Method for Producing Sterile Cannabis Sativa L. Cultivars

Abstract

The Method of Producing Sterile Cannabis sativa L. Cultivars includes applying a novel colchicine treatment to axillary meristems of diploid cannabis plants to produce sterile cannabis growth. The colchicine may be a range of concentrations applied over a 24 hour period to produce the sterile cannabis growth. The sterile cannabis plant will not reproduce sexually but may be replicated via other methods that are used to replicate plants.

Claims

1. A method of producing a sterile Cannabis sativa plant, the method comprising: applying a treatment of a colchicine solution to an axillary meristem of a four-leaf cannabis plant.

2. The method of claim 1, wherein the colchicine solution is between 0.1 percent by weight and 0.9 percent by weight.

3. The method of claim 1, further comprising: applying a second treatment of the colchicine solution to the axillary meristem of the four-leaf cannabis plant within 24 hours of the first treatment.

4. The method of claim 3, further comprising: applying a third treatment of the colchicine solution to the axillary meristem of the four-leaf cannabis plant within 24 hours of the first treatment.

5. The method of claim 1, wherein the colchicine solution is 0.2 percent by weight.

6. The method of claim 5, further comprising: the treatment includes applying a volume of 10 μL to 250 μL of the colchicine solution.

7. The method of claim 1, further comprising 50 μL of the colchicine solution is applied at the treatment.

8. The method of claim 1, further comprising after treatment with colchicine: producing a sterile cannabis plant.

9. The method of claim 8, wherein the sterile cannabis plant is triploid.

10. The method of claim 1, further comprising after treatment with colchicine: cutting an apical meristem of the cannabis plant; and placing the cannabis plant in a dark room for up to 48 hours.

11. A method for producing sterile Cannabis sativa, the method comprising: applying a first volume of a colchicine solution to an axillary meristem of a cannabis plant at least at a four-leaf growth stage; applying a second volume of the colchicine solution to the axillary meristem of a cannabis plant; and applying a third volume of the colchicine solution to the axillary meristem of a cannabis plant; wherein the first volume, the second volume, and the third volume are applied within a 24 hour period.

13. The method of claim 12, wherein the colchicine solution is between 0.1 and 0.9 percent by weight.

14. The method of claim 12, wherein the colchicine solution is 0.2 percent by weight.

15. The method of claim 12, wherein the first volume, the second volume, and the third volume are between 10 μL to 250 μL.

16. The method of claim 14, wherein the first volume, the second volume, and the third volume are 50 μL.

17. The method of claim 12, further comprising after applying the third volume: cutting an apical meristem of the cannabis plant; and placing the cannabis plant in a dark room for up to 48 hours.

18. A method of producing a sterile cannabis plant, the method comprising: treating a first cannabis plant with a colchicine solution to produce a polyploid cannabis plant; providing a second cannabis plant; and mating the polyploid cannabis plant with the second cannabis plant to produce the sterile cannabis plant.

19. The method of claim 18, wherein the sterile cannabis plant is a triploid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is an illustration of two cannabis plants at different growth stages.

DETAILED DESCRIPTION

[0020] This disclosure presents methods to produce sterile cannabis plants. Previous methods rely on tissue culture or treatment of germinating seeds and plants which had only developed to the 2-leaf stage (code 1002) to produce polyploid cannabis. The disclosed methods generate polyploids from plants that have reached at least the 4-leaf stage (code 1004). (The ‘codes’ are a system used to describe growth phases of hemp plants. See Mediavilla, Vito, Manuel Jonquera, Ingrid Schmid-Slembrouck and Alberto Soldati 1998. A decimal code for growth stages of hemp (Cannabis sativa L.). Journal of the International Hemp Association 5(2): 65, 68-74.).

[0021] In various embodiments discussed herein, sterile varieties of C. sativa were developed from seedlings, clones, and reciprocal crossing of an artificially created polyploid with a wildtype diploid.

[0022] Referring to FIG. 1, a plant at the 2-leaf stage 100 and a plant at the 4-leaf stage 200 are shown. In one exemplary embodiment of the Method of Producing Sterile Cannabis sativa L. Cultivars, an axillary meristem 202 of a wildtype, diploid cannabis plant 200 is treated with colchicine to produce polyploid growth which is then allowed to grow before removing the known diploid growth from the plant. In some embodiments, the wildtype, diploid cannabis plant is rooted with two levels of growth. In some embodiments, the cannabis plant 200 has grown to at least the 4-leaf stage. The cannabis plant to be treated may be rooted and have reached at least the 4-leaf stage of growth. By way of example, a cannabis plant with a second level of growth, with two leaves at each level, and sufficient rooting may be treated with a colchicine solution.

[0023] In one exemplary embodiment, when an axillary meristem 202 of the cannabis plant 200 at the 4-leaf stage is treated with colchicine, triploid growth is induced. Then, the triploid growth is allowed to grow before removing any remaining diploid growth. Diploid growth refers to any leaves or shoots of diploid growth prior to treatment of the axillary meristem 202 with colchicine.

[0024] In some embodiments, polyploid plants are created by treating the axillary meristems 202 of 1-month old seedlings (code 1004, or 4-leaves on two levels of growth) with a colchicine solution that is in the range of 0.1-1.0% by weight.

[0025] In some embodiments, the colchicine solution may be applied to the axillary meristem 202 three times in 24 hours. The colchicine solution may be applied at a volume from 10 μL to 250 μL at each of the three treatment times.

[0026] By way of example, a 4-leaf cannabis seedling may be treated with 50 μL of a 0.2% by weight colchicine solution, applied to the axillary meristems 202, three times within 24 hours, to create a triploid cannabis plant.

[0027] In some embodiments, the treated seedlings may be pruned to have apical meristems removed then placed in a dark room for 48 hours to encourage lateral growth immediately after treatment. After dark treatment, plants may then be moved to a greenhouse with 45% shade and with supplemental 16-hour lighting to maintain vegetative phase. After 2 weeks, new growth from the treated axillary buds will have polyploid chromosomes.

[0028] In other embodiments of the Method, triploids were created by crossing artificially produced polyploid cannabis plants with diploid genotypes. For example, a polyploid cannabis plant produced through treatment of colchicine may be induced to flower and cross or mate with a diploid cannabis plant. In some embodiments, a female diploid cannabis plant may be sex-reversed to become a pollen producer and mated with a female polyploid cannabis plant, created by treatment with colchicine, to produce a sterile female cannabis plant. In some embodiments, a female polyploid cannabis plant, created by treatment with colchicine, may be sex-reversed to become pollen donator and mated with a female diploid cannabis plant to produce a sterile female cannabis plant. In some embodiments, the sterile female cannabis plant produced through this method are triploid.

[0029] In some embodiments, the sterile female cannabis plant produced through the disclosed methods will produce sterile seeds. The sterile seeds may then be planted and grow into a sterile female cannabis plant. The sterile seeds develop and harden and can be planted without embryo rescue.

[0030] Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, all embodiments can be combined in any way and/or combination, and the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.

[0031] It will be appreciated by persons skilled in the art that the embodiments described herein are not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings.