Marijuana Horticulture: The Indoor/Outdoor Medical Grower's Bible
hybridizing or outcrossing phases of their breeding programs.
3 - Grow and evaluate.
Do just as it says. The more plants you grow, the more variations you will see. I am repeatedly surprised and even amazed to see new expression of traits when growing this fabulous species. Cannabis is an extremely variable and polymorphic species, many traits have numerous possible expressions. Growing varied seed stocks of different heritage (and many of each population) ensures the breeder a wide array of phenotypes and combinations of traits for future selection.
Choosing from as many plants as possible is always preferable; having a wide and diverse starting stock assures the highest chances of finding what you might be looking for. When selecting from just a few seeds, it’s not possible to assure all plants will be vigorous or show the traits of interest even if they are seeds of known quality. Breeders must weed through large populations of potential plants, and “rogue out” the undesirable individuals. In any breeding program, off-types which do not suit the goal should be removed from the breeding populations.
Some recessive traits, especially those controlled by multiple genes (polygenic traits), have the potential for phenotypes that are only apparent in 1 in 100 or even 1 in 1000 plants. Unless growing many individuals, the breeder has a very low likelihood of discovering these phenotypes. All other things being equal, the breeder who grows the most plants has the greatest possibility of finding the best breeding candidates. Testing the final product is a crucial part of the evaluation process, so get out that bong or those rolling papers and put all your hard work to the test!
4 - Screen, Select, and Apply Selection
Rogue out weak females.
Pressures.
To paraphrase one of the great breeders of the 20th century, select only plants that closely match your goal, and reject all others. This is an important rule to follow if your future generations are to gradually approach your goal.
Breeders select plants for future breeding on the basis of their desirable characteristics. There is no “right” or “correct” ranking of priority for selecting one trait over another; this is purely based on what traits are most important to the breeder. For indoor cultivation, these include short, squat, bushy growth; large, densely formed buds; discernible taste or particular flavors and aromas; high THC content and quality of high (long-lasting, soaring, sedative); and resistance to specific insects or diseases. It’s a good general rule to look for plants with overall vigor and good health.
Sometimes, we find a plant that is almost ideal in every respect, but has some negative trait that is undesirable. For example, the breeder may select a highly potent plant that produces exceptionally aromatic or flavorful flowers but is tall and lanky and difficult to grow indoors under artificial light. Even with this negative trait, the breeder decides the plant is a worthwhile breeding candidate. The breeder must realize and note that when selecting plants that may have some genetic weakness, the unwanted negative traits must be removed from the population at a later point. The breeder must balance positive and negative aspects of each plant as a possible genetic contributor to future generations.
When planting a large number of seeds, you will generally find that some plants differ greatly in regard to certain traits while being otherwise nearly identical. For example, some plants are more-or-less susceptible to fungal infection such as botrytis (grey mold) or powdery mildew. Once suitable plants are selected, they can be exposed to a particular pathogen or environment as a selection pressure; growing potential breeding parents in an environment may expose genetic strengths or weaknesses associated with a particular environment. For mold resistant varieties, select plants for future mating that resist mold in a mold prone environment. For potent varieties, select only the most potent plants, after harvest. If you require your plants finish at less that 6 feet of height, remove or only keep seeds from plants that mature at less than 6 feet. If you require an outdoor acclimated variety, perform your selection outdoors under those particular conditions, and put an emphasis for selection on plants that mature early enough to finish in your particular environment. Selecting the earliest of the most potent plants is a better way to
Weitere Kostenlose Bücher