Impact of Nitrogen Nutrition on Cannabis sativa: An Update on the Current Knowledge and Future Prospects

Cannabis Hunger Games: nutrient stress induction in flowering stage - impact of organic and mineral fertilizer levels on biomass, cannabidiol (CBD) yield and nutrient use efficiency

Indoor medicinal cannabis cultivation systems enable year-round cultivation and better control of growing factors, however, such systems are energy and resource intensive. Nutrient deprivation during flowering can trigger nutrient translocation and modulate the production of cannabinoids, which might increase agronomic nutrient use efficiency, and thus, a more sustainable use of fertilizers. This experiment compares two fertilizer types (mineral and organic) applied in three dilutions (80, 160 and 240 mg N L-1) to evaluate the effect of nutrient deprivation during flowering on biomass, Cannabidiol (CBD) yield and nutrient use efficiency of N, P and K. This is the first study showing the potential to reduce fertilizer input while maintaining CBD yield of medicinal cannabis. Under nutrient stress, inflorescence yield was significantly lower at the final harvest, however, this was compensated by a higher CBD concentration, resulting in 95% of CBD yield using one-third less fertilizer. The higher nutrient use efficiency of N, P, and K in nutrient-deprived plants was achieved by a larger mobilization and translocation of nutrients increasing the utilization efficiency of acquired nutrients. The agronomic nutrient use efficiency of CBD yield - for N and K - increased 34% for the organic fertilizers and 72% for the mineral fertilizers comparing the dilution with one-third less nutrients (160) with the highest nutrient concentration (240). Differences in CBD yield between fertilizer types occurred only at the final harvest indicating limitations in nutrient uptake due to nutrient forms in the organic fertilizer. Our results showed a lower acquisition and utilization efficiency for the organic fertilizer, proposing the necessity to improve either the timing of bio-availability of organic fertilizers or the use of soil amendments.

Chromosome-level genome and high nitrogen stress response of the widespread and ecologically important wetland plant Typha angustifolia

Typha angustifolia L., known as narrowleaf cattail, is widely distributed in Eurasia but has been introduced to North America. Typha angustifolia is a semi-aquatic, wetland obligate plant that is widely distributed in Eurasia and North America. It is ecologically important for nutrient cycling in wetlands where it occurs and is used in phytoremediation and traditional medicine. In order to construct a high-quality genome for Typha angustifolia and investigate genes in response to high nitrogen stress, we carried out complete genome sequencing and high-nitrogen-stress experiments. We generated a chromosomal-level genome of T. angustifolia, which had 15 pseudochromosomes, a size of 207 Mb, and a contig N50 length of 13.57 Mb. Genome duplication analyses detected no recent whole-genome duplication (WGD) event for T. angustifolia. An analysis of gene family expansion and contraction showed that T. angustifolia gained 1,310 genes and lost 1,426 genes. High-nitrogen-stress experiments showed that a high nitrogen level had a significant inhibitory effect on root growth and differential gene expression analyses using 24 samples found 128 differentially expressed genes (DEGs) between the nitrogen-treated and control groups. DEGs in the roots and leaves were enriched in alanines, aspartate, and glutamate metabolism, nitrogen metabolism, photosynthesis, phenylpropanoid biosynthesis, plant-pathogen interaction, and mitogen-activated protein kinase pathways, among others. This study provides genomic data for a medicinal and ecologically important herb and lays a theoretical foundation for plant-assisted water pollution remediation.

Synergistic and non-synergistic impact of HAP-based nano fertilizer and PGPR for improved nutrient utilization and metabolite variation in hemp crops

Nanofertilizer prepared with urea-hydroxyapatite amalgamation along with PGPR promotes urea availability over longer period of plant growth and reduces wasteful urea expense in soil, curtailing environmental pollution.

Pigment production by a newly isolated strain Pycnoporus sanguineus SYBC-L7 in solid-state fermentation

Natural pigments are playing important roles in our daily lives. They not only make products colorful but also provide various health benefits for humans. In addition, Pycnoporus genus, listed as food- and cosmetic-grade microorganism, is one of the promising organisms for developing natural pigments. In this study, a new fungal strain with high efficiency in producing intense orange pigments was isolated and identified as Pycnoporus sanguineus SYBC-L7. Different agro-industrial wastes were applied to evaluate the growth and pigment production of strain SYBC-L7. SYBC-L7 can grow rapidly and effectively produce pigments using wood chips as substrate in solid-state fermentation (SSF). Culture conditions were also optimized for value-added pigments production and the optimum production conditions were glucose as carbon source, ammonium tartrate as nitrogen source, initial pH 6.0, and relative humidity of 65%. Pigment components, cinnabarinic acid, tramesanguin, and 2-amino-9-formylphenoxazone-1-carbonic acid were confirmed by liquid chromatography–mass spectrometry. Meanwhile, an agar plate diffusion assay was performed to evaluate the antimicrobial activity of the pigment. These pigments showed more significant inhibition of Gram-positive than Gram-negative bacteria. The results showed that Pycnoporus sanguineus SYBC-L7 was able to cost-effectively produce intense natural orange pigments with antibacterial activity in SSF, which is the basis of their large-scale production and application.

Simple Extraction of Cannabinoids from Female Inflorescences of Hemp (Cannabis sativa L.)

The high interest in non-psychoactive cannabidiol increases the need for efficient and straightforward cannabidiol (CBD) extraction methods. The research aimed to compare simple methods of cannabinoid extraction that do not require advanced laboratory equipment. This work assesses the content of total CBD and Δ⁹-tetrahydrocannabinol (Δ⁹-THC) in popular solvents such as water and ethanol extracts. Hemp raw material was analyzed with Gas Chromatography with a Flame Ionization Detector (GC-FID), while extracts were tested by High-Performance Liquid Chromatography (HPLC). The female inflorescences of three varieties of industrial hemp were tested: Futura 75, KC Dora, and Tygra (different sowing and N fertilization densities). Tygra (T/10/30) showed the highest content of CBD (0.064%) in water extracts. However, in 80% tincture from Futura 75 (F/30/30), a higher CBD content of 1.393% was observed. The use of 96% ethanol for extraction and ultrasound enabled the highest CBD content to be obtained: 2.682% in Futura 75 (F/30/30). Cold water extraction showed no effect on Δ⁹-THC content, while hot water extraction increased content from 0.001% in KC Dora to 0.002% in Futura 75 (F/30/30) and Tygra, but the changes were statistically insignificant. Application of 80% ethanol revealed the significantly highest content of Δ⁹-THC in KC Dora, from 0.026% (K/30/90) to 0.057% (K/30/30), as well as in Tygra (T/30/30) (0.036%) and Futura 75 (F/30/30) (0.048%). The use of ethanol extraction in combination with ultrasound could be an efficient method of obtaining cannabinoids.

Downregulation of ammonium uptake improves the growth and tolerance of Kluyveromyces marxianus at high temperature

The growth and tolerance of Kluyveromyces marxianus at high temperatures decreased significantly in the synthetic medium (SM), which is commonly used in industrial fermentations. After 100 days of adaptive laboratory evolution, a strain named KM234 exhibited excellent tolerance at a high temperature, without loss of its growth ability at a moderate temperature. Transcriptomic analysis revealed that the KM234 strain decreased the expression of the ammonium (NH₄⁺) transporter gene MEP3 and increased the synthesis of the amino acid carbon backbone, which may contribute greatly to the high‐temperature growth phenotype. High NH₄⁺ content in SM significantly increased the reactive oxygen species (ROS) production at high temperatures and thus caused toxicity to yeast cells. Replacing NH₄⁺ with organic nitrogen sources or increasing the concentration of potassium ions (K⁺) in the medium restored the growth of the wild‐type K. marxianus at a high temperature in SM. We also showed that the NH₄⁺ toxicity mitigated by K⁺ might closely depend on the KIN1 gene. Our results provide a practical solution to industrial fermentation under high‐temperature conditions.

Industry-Based Misconceptions Regarding Cross-Pollination of Cannabis spp

Cross-pollination of commercial crops has been an ongoing issue in many species. Cannabis spp. encompasses the classifications of marijuana [high in Δ⁹-tetrahydrocannabinol (THC)] and hemp (below 0.3% THC). As such, cannabis is the most recent crop facing the dilemma of cross-pollination and is leading to litigation. These litigations are driven by the large misunderstanding of the impacts of cross-pollination within the cannabis industry. The misconception is that if hemp is cross-pollinated by high THC cannabis, the hemp will become "hot" (high in THC) thereby rendering the crop illegal under the 2018 Farm Bill. However, there are many factors that contribute to the amount of THC a plant may produce. This article examines and refutes the misconception of cross-pollination increasing THC levels by highlighting several methods of how THC may become high in a given hemp crop.

Potential impacts of soil microbiota manipulation on secondary metabolites production in cannabis

BACKGROUND

Cannabis growing practices and particularly indoor cultivation conditions have a great influence on the production of cannabinoids. Plant-associated microbes may affect nutrient acquisition by the plant. However, beneficial microbes influencing cannabinoid biosynthesis remain largely unexplored and unexploited in cannabis production.

OBJECTIVE

To summarize study outcomes on bacterial and fungal communities associated with cannabis using high-throughput sequencing technologies and to uncover microbial interactions, species diversity, and microbial network connections that potentially influence secondary metabolite production in cannabis.

MATERIALS AND METHOD

A mini review was conducted including recent publications on cannabis and their associated microbiota and secondary metabolite production.

RESULTS

In this review, we provide an overview of the potential role of the soil microbiome in production of cannabinoids, and discussed that manipulation of cannabis-associated microbiome obtained through soil amendment interventions of diversified microbial communities sourced from natural forest soil could potentially help producers of cannabis to improve yields of cannabinoids and enhance the balance of cannabidiol (CBD) and tetrahydrocannabinol (THC) proportions.

CONCLUSION

Cannabis is one of the oldest cultivated crops in history, grown for food, fiber, and drugs for thousands of years. Extension of genetic variation in cannabis has developed into wide-ranging varieties with various complementary phenotypes and secondary metabolites. For medical or pharmaceutical purposes, the ratio of CBD to THC is key. Therefore, studying soil microbiota associated with cannabis and its potential impact on secondary metabolites production could be useful when selecting microorganisms as bioinoculant agents for enhanced organic cannabinoid production.

Draft genome of Puya raimondii (Bromeliaceae), the Queen of the Andes

Puya raimondii, the Queen of the Andes, is an endangered high Andean species in the Bromeliaceae family. Here, we report its first genome to promote its conservation and evolutionary study. Comparative genomics showed P. raimondii diverged from Ananas comosus about 14.8 million years ago, and the long terminal repeats were likely to contribute to the genus diversification in last 3.5 million years. The gene families related to plant reproductive development and stress responses significantly expanded in the genome. At the same time, gene families involved in disease defense, photosynthesis and carbohydrate metabolism significantly contracted, which may be an evolutionary strategy to adapt to the harsh conditions in high Andes. The demographic history analysis revealed the P. raimondii population size sharply declined in the Pleistocene and then increased in the Holocene. We also designed and tested 46 pairs of universal primers for amplifying orthologous single-copy nuclear genes in Puya species.

Silicon-induced mitigatory effects in salt-stressed hemp leaves

Silicon, a quasi-essential element for plants, improves vigour and resilience under stress. Recently, studies on textile hemp (Cannabis sativa L.) showed its genetic predisposition to uptake silicic acid and accumulate it as silica in epidermal leaf cells and trichomes. Here, microscopy, silicon quantification and gene expression analysis of candidate genes involved in salt stress were performed in hemp to investigate whether the metalloid protects against salinity. The results obtained with microscopy reveal that silicon treatment ameliorated the symptoms of salinity in older fan leaves, where the xylem tissue showed vessels with a wider lumen. In younger ones, it was difficult to assess any mitigation of stress symptoms after silicon application. At the gene level, salinity with and without silicon induced the expression of a putative Si efflux transporter gene 2 (low silicon 2, Lsi2). The addition of the metalloid did not result in any statistically significant changes in the expression of genes involved in stress response, although a trend towards a decrease was observed. In conclusion, our results show that hemp stress symptoms can be alleviated in older leaves by silicon application, that the metalloid is accumulated in fan leaves and highlight one putative rice Lsi2 orthologue as responsive to salinity.

Phyto-Courier, a Silicon Particle-Based Nano-biostimulant: Evidence from Cannabis sativa Exposed to Salinity

Global warming and sea level rise are serious threats to agriculture. The negative effects caused by severe salinity include discoloration and reduced surface of the leaves, as well as wilting due to an impaired uptake of water from the soil by roots. Nanotechnology is emerging as a valuable ally in agriculture: several studies have indeed already proven the role of silicon nanoparticles in ameliorating the conditions of plants subjected to (a) biotic stressors. Here, we introduce the concept of phyto-courier: hydrolyzable nanoparticles of porous silicon, stabilized with the nonreducing saccharide trehalose and containing different combinations of lipids and/or amino acids, were used as vehicle for the delivery of the bioactive compound quercetin to the leaves of salt-stressed hemp (Cannabis sativa L., Santhica 27). Hemp was used as a representative model of an economically important crop with multiple uses. Quercetin is an antioxidant known to scavenge reactive oxygen species in cells. Four different silicon-based formulations were administered via spraying in order to investigate their ability to improve the plant's stress response, thereby acting as nano-biostimulants. We show that two formulations proved to be effective at decreasing stress symptoms by modulating the amount of soluble sugars and the expression of genes that are markers of stress-response in hemp. The study proves the suitability of the phyto-courier technology for agricultural applications aimed at crop protection.