Cannabis has a long history of use dating back to the third millennium BCE, when it was utilized for various purposes on the Asian continent. During the Middle Ages, it spread to Europe and later to both Americas. In the 20th century, its significance declined due to pressures related to its psychoactive effect. However, today it is once again gaining positive recognition, especially as a medicinal and industrially useful plant. As a dioecious plant, cannabis has separate male and female plants. For the cultivation of flowers for medicinal use, only unfertilized female plants, which have a sufficient amount of cannabinoids, are suitable. Feminized seeds can be used to ensure the cultivation of only female plants. The production of feminized seeds requires inducing the development of male flowers on genetically female plants, enabling fertilization and the subsequent creation of feminized seeds. The technique is also used for breeding cannabis for medical use. Among the most effective methods of manipulating sex expression, the use of silver compounds, such as silver thiosulfate and silver nitrate, has proven to be the most successful so far. Other methods, such as the use of growth regulators (e.g., gibberellic acid) and the adjustment of environmental factors, especially lighting, have also been tested.
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