Methods for manipulating yield and generation time of short day plants grown in a field environment are provided. The methods comprise manipulating external signals such as photoperiod in order to increase the per plant seed yield. Also provided are methods for synchronizing the flowering times of plants in different maturity groups.

A method for promoting the accumulation of cannabinoid substances is disclosed. The method comprises the step of adding an irradiation of green light, which has a peak wavelength at 505-526 nm, into the indoor growing environment of cannabis to improve the levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), cannabinoid substances in cannabis. While maintaining the light intensity and other growth conditions, the yields and/or levels of THC and CBD, cannabinoid substances in cannabis, can be increased by up to 21.35%.

A method for promoting the accumulation of cannabinoid substances is disclosed. The method comprises the step of adding an irradiation of green light, which has a peak wavelength at 505-526 nm, into the indoor growing environment of cannabis to improve the levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), cannabinoid substances in cannabis. While maintaining the light intensity and other growth conditions, the yields and/or levels of THC and CBD, cannabinoid substances in cannabis, can be increased by up to 21.35%.

A method of producing cannabinoids for use in medical treatments by growing cultured Cannabis sativa plant cells through tissue culture, the method comprising the steps of: selecting Cannabis sativa leaf tissue for culture; and growing a tissue culture from the selected leaf tissue in a liquid based medium whilst controlling the light exposure of the tissue culture to control the cannabinoid content of the tissue culture. Control of the light exposure can enable the phytocannabinoid content of the grown tissue culture to be tailored to the use intended for the tissue culture. For example, the THC content of the tissue culture can be controlled to be maximised or minimised depending on the intended use. Use of tissue culture is beneficial as compared to prior art methods as it allows for genetic consistency and reduces the resources necessary to produce plant cells containing phytocannabinoids.

A method of producing cannabinoids for use in medical treatments by growing cultured Cannabis sativa plant cells through tissue culture, the method comprising the steps of: selecting Cannabis sativa leaf tissue for culture; and growing a tissue culture from the selected leaf tissue in a liquid based medium whilst controlling the light exposure of the tissue culture to control the cannabinoid content of the tissue culture. Control of the light exposure can enable the phytocannabinoid content of the grown tissue culture to be tailored to the use intended for the tissue culture. For example, the THC content of the tissue culture can be controlled to be maximised or minimised depending on the intended use. Use of tissue culture is beneficial as compared to prior art methods as it allows for genetic consistency and reduces the resources necessary to produce plant cells containing phytocannabinoids.

A method for promoting the accumulation of cannabinoid substances is disclosed. The method comprises the step of adding an irradiation of green light, which has a peak wavelength at 505-526 nm, into the indoor growing environment of cannabis to improve the levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), cannabinoid substances in cannabis. While maintaining the light intensity and other growth conditions, the yields and/or levels of THC and CBD, cannabinoid substances in cannabis, can be increased by up to 21.35%.

A method for promoting the accumulation of cannabinoid substances is disclosed. The method comprises the step of adding an irradiation of green light, which has a peak wavelength at 505-526 nm, into the indoor growing environment of cannabis to improve the levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), cannabinoid substances in cannabis. While maintaining the light intensity and other growth conditions, the yields and/or levels of THC and CBD, cannabinoid substances in cannabis, can be increased by up to 21.35%.

The present invention provides a method for improving a one-time seedling rate of microspore embryoids of Brassica campestris ssp. Chinensis Makino, including the steps of: spraying 6-BA onto a flower bud of a plant; sterilizing the flower bud with alcohol and HgCl.sub.2; releasing microspores, filtering and centrifuging to obtain purified microspores; diluting the microspores with a NLN medium, subpackaging into culture dishes, and adding phytic acid; finally, subjecting to heat shock treatment and transferring to culture in the dark until embryoids appear, and then conducting shaking culture; transferring the cultured embryos in a cotyledon stage onto a MS medium for differentiation culture, wherein the culture conditions are: 4° C., 14 h of illumination by blue-red compound light/day, and 14 days of culture; and then continuing to culture under the condition of 25° C. and 14 h of illumination by blue-red compound light/day until seedlings.

Provided herein are methods, compositions, and devices relating to administration of UV-B to a seed.

Provided herein are methods, compositions, and devices relating to administration of UV-B to a seed.