A study published in the Journal of Cannabis Research examined the impact of two biofertilizers (manure tea and bioinoculant) and one humic acid (HA) product on cannabis growth. The researchers analyzed the biochemical and physiological parameters and soil CO2 developments associated with outdoor cannabis cultivation conditions. The researchers conducted the study in two main phases in 2019 and 2020.
The research team hypothesized that HA would increase the microbial activity in the biofertilizers. They also projected that the synergy of both compounds would enhance plant performance and activate soil microbials.
The team found more significant impact under suboptimal growing conditions and observed differences in the two growing seasons that indicated the efficacy of biostimulants is optimized under stress conditions. The 2019 growing season reflected a planting date in an ideal cultivation period. As a result, chlorophyll content and photosynthetic efficiency were the only parameters affected by the use of biostimulants. The 2020 growing season had a planting delay which results in discrepancies between the two seasons. The researchers observed a greater impact of biostimulants under suboptimal growing conditions. This finding corroborates evidence from other studies that pointed to biostimulants effectiveness under stress conditions. The individual and combined application of biofertilizers and HA significantly increased cannabis height, chlorophyll content, photosynthetic efficiency, above ground biomass, and bucked biomass during the 2020 season.
The combined and individual use of biofertilizers and HA affected cannabis biochemical and physiological parameters such as vigor, chlorophyll content, greenness, height, photosynthetic efficiency, vigor, above ground biomass, and bucked biomass. The researchers noted this effect took place when the growing conditions were not optimal.
The study’s findings indicated that the biostimulants could enhance cannabis yield and quality during stress exposure periods. Biostimulants can help facilitate bioavailability of nutrients and nutrient uptake. The researchers suggested that cannabis cultivators can use biofertilizers and HA as a potential preventive strategy against biotic and abiotic elements. The researchers also noted that data analysis did not suggest that the combined use of biofertilizer + HA is more effective than individual application. Both methods vary in how they influence plant parameters throughout the growing season.
The study highlights the need for extensive research is needed to determine optimum biofertilizer and stimulants combinations.
Source: Journal of Cannabis Research
