Feminized
Feminized plants come from seeds that have been selectively bred to produce only female plants. Since female plants are the ones that produce flowers (which is where most of cannabis' cannabinoids are found), they are the only ones that are used to create marijuana products. Feminized seeds are intended to make things easier for growers by eliminating the need to determine the sex of growing plants and remove males early on to prevent fertilization. Generally, feminized seeds produce the same quality of plants as naturally produced seeds. nstability of gender is a desirable trait in the wild, where reproduction is the most urgent goal. In cultivation, gender predictability is more helpful, because female plants that have not been pollinated are the most productive of the psychotropic material. It is possible to use a combination of cloning and "shocking" of plants to get them to produce feminized seeds that reliably produce female offspring. A clone retains the same sex throughout its life, so the clone of a female plant is also female.
Environmental stresses sometimes create pollen bearing male flowers on female plants—known as hermaphroditism or 'hermying'.
A method used by organic growers and promulgated by the cannabis breeder Soma, is called 'Rodelization', or letting un-pollinated female plants live several weeks longer than the normal harvest time. In such plants a hermaphroditic trait self-expresses in an effort to continue the genetic line.
Some vendors of feminized seeds assert that hermaphroditic "parents" do not create reliable feminized seeds, since the offspring may retain the tendency of hermaphrodytism. Others believe that this method utilizing auto-hermaphroditic traits is offset by grower observations that the tendency to auto-switch sex is no greater in plants grown from seeds made this way, than occurs naturally.
Colloidal silver (commonly abbreviated CS) suppresses ethylene production in bud sites, stimulating male characteristics. Spraying selected leaves, branches and – in cases where a large amount of seed is desired – whole plants with colloidal silver solution has become a preferred method of obtaining feminized seeds. Most plants treated with CS will turn intersex within 2 weeks of triweekly treatment, producing viable pollen within 4. Gibberellic acid has also been used for the same purpose, but it is harder to acquire than colloidal silver and can be difficult to dissolve into solution. One method of obtaining colloidal silver utilizes a small direct current power supply and two pieces of solid silver jeweler's wire, or silver coin.[citation needed]
Some cultivators claim that the genes responsible for hermaphroditism are present and may be expressed under stress from any of the above methods and that once expressed, this characteristic passes to seeds regardless of what activated it. This view, in large part, is incorrect, as a random half of the genes present in each of the parental plants passes to the next generation, regardless of whether the genes that contribute to hermaphroditism were induced by stressors or not. This widely accepted Mendelian model of inheritance (Mendelian inheritance) does allow for genetic mutations that have occurred in the germline (Germline) of an organism to be passed on to any offspring, but this process applies to all DNA sequences, not just those contributing to hermaphroditism. The inheritance of acquired characteristics (Lamarckism) that are not directly coded in the DNA sequence (Epigenetics) has recently received much attention in the area of genetic research and could possibly explain any anecdotal evidence for increased hermaphroditism in the offspring of plants induced to a hermaphroditic state. However, a more likely explanation is that by propagating plants easily induced to hermaphroditism by environmental stressors, the frequency of genetic elements contributing to this trait is increased by artificial selection following traditional genetic models of inheritance. Some theories suggest it is possible to selectively breed hermaphroditic cannabis to express the female flowering before the male flowering occurs, though this kind of selective breeding is beyond the capabilities of most cultivators.