Regular seeds can produce either male or female plants. This is why growers who choose this type of seed must make sure that they cultivate enough plants to cover the potential number of males produced.
Male plants pollinate female plants and reduce the final yield per crop, so it is important to identify them and remove them. This can be time consuming and difficult for novice growers.
Breeding
Breeding is the process of crossing plants in order to produce offspring with desired traits. Cannabis is a dioecious plant, meaning it produces male and female plants with their own reproductive organs. This means that in order to create new strains, breeders must isolate and select the female plants and cross them with a male plant.
This can be a time-consuming and messy process, as male pollen will often spread to nearby female plants and cause them to become pollinated (hence producing seeds). Professional breeders usually work in dedicated breeding rooms to prevent this and have people change clothes and shower before working with different branches or areas of the plant in order to minimise accidental cross contamination.
Once the F1 hybrids are created breeders will backcross them to their original parent in order to stabilise desirable traits. This is known as regular seed lineage and can result in some very stable cultivars.
Cloning
Clones are exact genetic copies of a mother plant, so they will carry over all her traits and characteristics. Clones can also be faster to grow and flower compared to seeds. They also take less space because they are biologically mature and already in the vegetative stage. However, growing clones can still be tricky for home growers, as they must work in a sterile environment and disinfect their razors and scissors.
Another issue is that clones can carry pests and diseases from their parent plants. Clones should only be taken from healthy, stout plants that are at least two months into their vegetative cycle and have a large enough branch to cut. Check for signs of disease, like limping leaves, and pests, such as fungus gnats and spider mites, which leave spots and webbing on their victims. Additionally, clones can have trouble rooting properly in the wrong kind of growing medium. This can be a result of improper lighting, temperature, or soil conditions.
Genetic Diversity
Seed size and number are two highly heritable traits whose variation is affected by a large number of QTL. The genetic architecture of these traits differs from that of other life-history traits such as flowering time (Aarssen and Clauss 1992; Kover et al. 2009a). Although a significant negative correlation between seed size and seed number is observed, the correlation is relatively weak and the amount of variation explained by it is smaller than for other life-history traits.
The results suggest that the trade-off between seed size and seed number is not as strong as predicted by theoretical models. They also highlight the importance of examining mating systems to maximize genetic representation in seed collections for conservation targets. The results show that the mating system profoundly affects gene pool diversity and that consideration of this should be a key consideration for designing sampling strategies for ex situ collections. In addition, the findings demonstrate that seed collection from populations and seeds should be undertaken at different times to maximise the chances of capturing rare alleles.
Organic
Organic farmers need good quality seed to be able to produce the crops that their customers demand. They are also required to use seeds that perform well in local conditions. By developing their own organic seed systems – which involve saving and planting on-farm-bred varieties, as well as plant breeding – they can become more self-sufficient and less dependent on a conventional seed industry based on chemical inputs.
While European countries are required to list the organically produced seed of each variety on a national database, it remains possible for farmers to obtain general authorisation to use non-organic seed for a wide range of crop species. This is despite the fact that the new European organic regulation will phase out derogations in 2036. A structural equation model suggests that a farmer’s intention to use organic seed is mainly influenced by his or her perception of societal expectations, in particular those coming from the consumer and their organic certifier.
