Employing Aeroponic Systems for the Clonal Propagation of Cannabis

Summary

This protocol is designed to provide instructional information for the clonal propagation of Cannabis sativa L. by implementing aeroponic systems. The method described here includes all necessary supplies and protocols to successfully reproduce desirable morphological and chemical properties in the genus Cannabis.

Abstract

This protocol describes the standardization of an efficient clonal propagation technique of hemp by utilizing aeroponic systems. Primary shoot cuttings were excised from two hemp varieties, named "Cherry Wine" and "Red Robin" (17-20% w/w CBD), that served as 'mother plant'. An auxin precursor (indole-3-butyric acid) was applied to stimulate root development in the basal portion of the excised cuttings prior to placement in the system. Cuttings were lightly misted with the nutrient mist solution every three days to provide nutritional support as the solution contains the essential macronutrients, including nitrogen, phosphorus, and potassium. The aeroponic system water reservoir maintained a pH range between 5.0-6.0 and a water temperature between 20-22 °C. A submersible water pump was used to deliver water to the cuttings. The shoot tip cuttings were provided with 24 h of light per day for 10 days until root development occurred, upon which the rooted cuttings were transplanted for research purposes. These aeroponic systems have proven to generate desirable results for Cannabis propagation. The method described here alleviates potential time constraints that arise from traditional methods to allow for a more efficient means for the asexual propagation of Cannabis.

Introduction

Cannabis sativa L. is an annual, dioecious, flowering plant classified in the family Cannabaceae. Cannabinoids, produced predominantly within glandular trichomes located on the outer epidermal layer of bract tissues on female inflorescences¹, are becoming an increasingly popular research topic, primarily due to their progressively recognized medicinal properties. Cannabidiol (CBD) is the second most prominent cannabinoid found in Cannabis after Δ⁹-tetrahydrocannabinol (THC) and is attributed to a host of medicinal benefits, including analgesic properties², anti-seizure prope....

Protocol

1. Generation of a mother plant for clonal propagation

1. Select a healthy, female mother plant that exhibits desirable morphological and chemical characteristics specific to its intended use.
2. Allow the mother plant to reach the appropriate size (roughly 25 mature shoots) for clonal propagation (i.e., cuttings).
3. Allow the mother plants to remain in the vegetative growth stage (light: dark = 18 h:6 h) to promote shoot growth for future propagation.

2. Construction and preparation of aeroponic system

1. Begin by positioning the lid on top of the container (38.1 cm ....

Results

To validate the efficiency of the described aeroponic system, a total of 10 and 12 healthy 14 cm long shoots were excised from the mother plants, 'Cherry Wine' and 'Red Robin', respectively (Figure 1A,B). After dipping into rooting induction media, the clones were placed into the system (Figure 2A). The construction and operation of an aeroponic system is shown as a schematic diagram in Figure 2A.

Discussion

With the increasing demand for Cannabis plants with consistent cannabinoid content, various clonal propagation methods have been exploited in Cannabis industry. The asexual propagation shows several advantages over sexual methods for large-scale, consistent production. An aeroponic propagation system is a modified version of a hydroponic system that utilizes an aerated nutrient-rich water mist to provide rapid root development. The described aeroponic system is composed of three critical steps, 1) gener.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
1-part Fox Farm	Fox Farm		Soil Mix
1-part Promix	Promix		Soil Mix
1-part Roots Organic Original	Auora Innovations		Soil Mix
1-part Wiggle Worm Earth Worm Castings	UNCO Industries		Soil Mix
Algae and Bacterial Cleaning Solution (Clear Rez)	EZ Clone	SKU#: 225	8 fl. Oz.
Artificial Lighting	AgroBrite	SKU#: 1399	T5 324W 4' 6-Tube Fixture with Lamps
Cannabis Mother plant 1 (Cherry Wine)	Summit CBD	N/A	Donated material
Cannabis Mother Plant 2 (Red Wine)	Trilogene	SKU: 0101RR
Corresponding Plastic Lid	Office Depot	N/A	38.1 cm x 25.4 cm
Drill Bit 1	Dewalt	DW1586	38.1 mm spade drill bit
Drill Bit 2	Dewalt	DW1308	3.175 mm drill bit
Flora/Bloom (Nutrient Solution)-5 mL	General Hydroponics	SKU#: 726	946 mL (1 Quart) 2.43 lbs. (1.1 kg) (Available Phosphate 5.0%, Soluble Potash 4.0%, Magnesium 1.5%, Sulfur 1.0%)
FloraGrow (Nutrient Solution)- 5 mL	General Hydroponics	SKU#: 724	946 mL (1 Quart) 2.43 lbs. (1.1 kg) ((Total Nitrogen 2.0% (0.25% Ammoniacal Nitrogen, 1.75% Nitrate Nitrogen), Available Phosphate 1.0%, Soluble Potash 6.0%, Magnesium 0.5%))
FloraMicro (Nutrient Solution)- 5 mL	General Hydroponics	SKU#: 759	946 mL (1 Quart) 2.43 lbs. (1.1 kg) ((Total Nitrogen 5.0% (0.3% Ammoniacal Nitrogen, 4.7% Nitrate Nitrogen), Soluble Potash 1.0%, Calcium 5.0%, Boron 0.01%, Cobalt 0.0005%, Copper 0.01%, Iron 0.1%, Manganese 0.05%, Molybdenum 0.0008%, Zinc 0.015%))
Horticultural Scissors	Shear Perfection	SKU#: 12620	Platinum Stainless Steel Bonsai Scissors (2.4")
Isopropyl Alcohol	Equate	Walmart # 574133562	70% concentration
Nutrient Mist Solution (Clonex Mist)	Growth Technology	SKU#: 4889	10.14 fl. Oz (300 ml) (Total Nitrogen: 5.9 × 10-4 %, Available Phosphate: 4.0 × 10-4 %, Soluble Potash: 5.0 × 10-4 %)
pH Down	General Hydroponics	SKU#: 733	946 ml (1 Quart) 2.43 lbs. (1.1 kg)
pH Up	General Hydroponics	SKU#: 730	946 ml (1 Quart) 2.43 lbs. (1.1 kg)
Plastic Container	Office Depot	N/A	38.1 cm x 25.4 cm x 30.48 cm
Power Drill	Dewalt	DCD709B	20-Volt Max ½” Drill
Rockwool Cubes	Grodan	SKU#: 830	38.1 mm
Rooting Solution (Clonex Rooting Gel)	Growth Technology	SKU#: 939	3.4 fl. Oz. (100 ml) (Indolebutyric Acid - 0.31%)
Statistic Software (Prism)	GraphPad Inc.
Submersible Water Pump	ActiveAQUA	SKU: AAPW250	Model: AAPW250, Voltage 120V, Power 16W