growing weed: what is the science
TRANSCRIPT
Growing weed: What is the Science
Ashwell R Ndhlala PhD, DPhilAgro-processing of Medicinal Plants
Agricultural Research CouncilVegetable and Ornamental Plant Institute
Crop SciencePrivate Bag X293, Pretoria 0001, South Africa
Pharmaconnect- Medical Cannabis Symposium05 April 2019
Agro-processing
History of weed- Medical cannabis
Cannabis:• Genus name first recorded in 440BCE (by Herodotus)• Segregated into Cannabis sativa and C. indica
History of weed- Medical cannabis
Terminology…..
Hemp vs Marijuana:• Originated from Mexican Spanish- no exact meaning• Popularized in the 1930s…
Terminology…..
Hemp:• Low content of THC (<0.3%)• Cultivated for thousands of years for commercial fiber
THC: Tetrahydrocannibinol vs CBD: Cannabidiol
High THCMixed CBD & THC
Agro-processing
Potential resource-base
for extensive new value-products
(industrial, pharmaceuticals, crop-plants, agro-chemicals)
Southern Africa “Cannabis use”
High interests from government, research institutes,
private sector and individuals
Potential for agro-processing sector
Traditional medicine
Utilised in:• Phytomedicines• Herbal products and teas
Also includes: • Health foods• Cosmeceuticals
• Nutraceuticals
…derived from cannabis
Other potential uses
A resource under strain
Supply of plant material has to be increased in order to
meet the increasing demand for weed
solutions
Quality control starts in the field
Good Agricultural Practices- GAPs
What are the available tools
Cultivation
Micropropagation Seed propagation
Biotechnology
?
• Selective breeding• Seed development and culture• Plant hormone physiology• Tissue culture• Germplasm conservation• Transgenic plants• Genetic engineering• Smoke• Earthworms• Seaweeds• Soil micro-organisms
What are the available technologies
Smoke-waterVermicompost
leachatesSeaweed extracts
Plant Biotechnology
Few images capture the resiliency and tenacity of life
more than the emergence of young, green seedlings
through black, charred soil.
P.V. Minorsky (2002)
Boophone disticha
Smoke technology
OO
O
CH3
Butenolide Control
Smoke Water 1:500
Smoke Water 1:250
Smoke technology
OO
O
CH3
Butenolide
ControlSmoke Water
1:500Smoke Water
1:250
Smoke Water 1:1000
4-month-old Eucomis autumnalis plants
Research Centre for Plant Growth & Development
Onion
Smoke-technology
Control Smoke-waterButenolide
Onion (6-month-old plants)
Research Centre for Plant Growth & Development
• Pseudomonas fluorescens as a
biocontrol measure
• It secretes potential antibiotics
that are lethal to plant pathogens
• Promotes plant growth by
suppressing pathogens in root
zone and upper parts, and also
help in nutrient assimilation
• Synthesizes phytohormone IAA
• Multiple plant growth promoting
and biocontrol propertiesPseudomonas fluorescens
Plant Growth Promoting Bacteria
Space maximization….
C + Pf VCL + Pf
Enforce regulations on:
• Establish sound cultivation practices
• product quality, dosages and standardization
• Establish testing labs- ethnopharmacology
– Efficacy
– Safety
What can be done to ensure quality?
Ethnopharmacology tests
Confirming bioactivity is therefore critical as it offers direction forproduct development, and provides scientific rationale for traditional
usage
In vitro and in vivo assays bacterial, fungal,
helminthic, malarial, inflammatory, oxidant,
depressant
The myth of medicinal cannabis- Safety issues
• Unhygienic practices:
– Adulteration
Formulation stability test
During storage:
➢ Reduction in odor
➢ Changes in colour
➢ Smooth texture
➢ Decrease in pH
What must be done
What tools are available
politics emotion economics
Resources (biodiversity) must be used as parsimoniously as
possible (biotechnology) to meet current needs without
compromising the same ability of future generations
?What are the risks
Conclusions
