The Ultimate Guide To Pheno-Hunting

Cannabis is an amazing plant for a wide variety of reasons. However, it’s the genetic diversity of cannabis as a species that truly sets it apart from most of the other crops that are grown and cultivated by humans. Be sure to leave us a comment after reading through the following ultimate guide to pheno-hunting.

Cannabis has grown wild as well as having been cultivated with specific intent on six continents (probably seven) for thousands of years and used for myriad purposes beyond the popular medicinal and recreational applications. Hemp bast fibers can be turned into clothing, paper and incredible durable building materials. The seeds can be eaten raw, cooked or pressed for their nutritious oil. The flowers can be used for… decorative purposes…

Whatever you want to use your cannabis for you’ll want to make sure you’re growing an appropriate phenotype. Due to the massive amount of diversity present in the cannabis gene pool, also known as population-level genetic variation, there is a vast palette of starting material to choose from. 
Having appropriate phenotypes is like making sure you’re painting with the right colors – or better yet – having the right tool for the job. Factors such as how acclimated a particular variety is to the local environment will have a massive impact on overall vigor, sexual stability of females, pest and disease resistance, and more. You also don’t want to be growing a variety that has a completely different cannabinoid or terpene profile than you’re looking for.

Female cannabis phenotype

Mature female flower
This article has been written to provide an overview of the pheno-hunt process. We’ll dive into some best practices around defining your goals and expectations, how to plan and organize a pheno-hunt, how to source seeds, and more. We’ll also provide a detailed step-by-step walkthrough for how to conduct your first pheno-hunt. There are many ways to define a successful pheno-hunt, and myriad opinions about how to manage your plants during a project like this. That’s why we provide a highly effective, efficient and pragmatic method to ensure your pheno-hunting efforts will be extremely productive.

A pheno-hunt, or phenotype-hunt, is a search for new cultivars (a.k.a. “strains” or varieties) of a plant that have a unique set of physical traits. The word phenotype can be defined as the overall expression of a set of physical traits – although the word phenotype can also be used to describe one or a few very specific physical trait(s). Furthermore, because we know that phenotypes are composed of the combination of genetics and environment (nature and nurture); when we select for new phenotypes we’re actually selecting for particular underlying genetic variation (genotypes). 
The process of pheno-hunting is essentially the application of a selection protocol to the final stage of a breeding project. To conduct a pheno-hunt, you must start with a large batch of seeds that contain a lot of genetic variation. The only way to obtain seeds like that is from a breeding project between two different cultivars. ​A few high quality breeders produce seeds that are backcrossed to achieve stable phenotypes, however, you’ll want to inquire with your source to find out how much variation you should expect in a given lot of seed.
It’s often the case that the parental cultivars will be listed when purchasing a batch of seeds, so that the cultivator growing them will have some idea of the potential genetic variation contained within those seeds. When someone wants to conduct a pheno-hunt, they obtain seeds from interesting breeding projects then grow the plants and select for the most interesting cultivars.
There are often some very intentional goals of conducting a pheno-hunt. Depending on what you want to accomplish several variables in the process are going to need to be adjusted and accounted for differently. This is going to affect what seed stocks you choose to start with and how you select for particular phenotypes throughout the process. Some cultivators look for traits like growth structure, hardiness, terpene profile, appearance, trichomes and peak maturity time.

Purple cannabis phenotype from anthocyanin expression

Purple cannabis phenotype
Pheno-hunts are often deployed when launching a new cultivation program or when a company first gets started. They’re also often used when a solo grower or business wants to expand their collection to include new cultivars with different qualities than the plants they already maintain in their garden. Different characteristics such as morphology and growth rate are important factors to consider in addition to flavors and smells. ​​
For example, if you want to grow hemp you’ll want to make sure you’re starting with a seed stock that doesn’t contain active enzymes to produce THC. You’ll also want to identify which cannabinoids you’ll be growing for and what your cultivars will be used for. If you’re growing for extracting isolates then you might not care as much about terpene profile and instead focus more on dry-mass yield of your target cannabinoids. 
In turn, if you’re growing to produce top-shelf flowers then you’re going to want to select for cultivars with incredible visual and olfactory appeal, while also considering the underlying cannabinoid and terpene content, and the overall effects produced when the flower is consumed.

Setting up a selection for new cultivars can be like solving a jigsaw puzzle and drawing the picture for the puzzle at the same time. There are a lot of variables to consider beyond finding and sourcing appropriate genetic material. 

However, planning and defining the goals of your project are the most important steps, so don’t rush this. Master cultivators and breeders including Ed Rosenthal, Professor P and Dynasty Genetics, Jen Norstar and Big Buddha Seeds all have discussed the importance of having clear goals and structure in place for any phenotype selection or breeding program.

First, you’re going to want to make sure you have enough space to account for all the seeds you plan on germinating to start the process, as well as cuttings from each of those plants once they get bigger. Deciding exactly how many seeds to germinate can be a difficult process because you need to plan several generations down the road – and to have multiple generations coordinated at the same time.

In addition to planning your space requirements you’ll also want to consider if you’ll need any additional hands at key points in the process. Managing a large number of plants and transitioning between the stages of a pheno-hunt can be very time-consuming and time-sensitive.

You’ll also want to make sure you have enough grow media, pots, cloning equipment, drying racks, curing jars, and plant tags or other ways to label and track all your plants. Putting together a naming scheme to track your plants before starting is also a good idea. Last but not least, define your criteria for selection (including the traits you will score) before getting started to keep your observations and records objective once the hunt is underway.

We already talked about how important it is to plan out everything. You might even want to consider working with a company like Delta Leaf to help run your hunt. Once you’re set there, the first thing to actually get your hunt started is to begin searching for appropriate seed stock. 

You’ll want to make sure you can legally obtain any seeds you’re interested in. Another important factor to consider is whether the seed stocks you’re looking at will give you the kinds of phenotypes you want to fulfill your ultimate end-goals in the cultivation realm. It’s also important to consider your budget before you get too excited. Determining how many seeds you can afford that will give you the best chances of finding amazing plants with the traits you want.

Male cannabis phenotype

Male cannabis phenotype
Once you have all the pieces in place and have secured your genetic starting material the next step is going to be growing the plants and keeping to the plan. Using services like Plant DNA Sex/Gender Identification and Cannabinoid Genotype Testing can help you narrow down the gene pool early on in the selection process. 
There are no hard and fast rules for how to conduct a pheno-hunt, what parameters should be used at each stage in the process, how to score the phenotypes or even what traits should be scored, or whether you should just ignore the numbers all together and go with your instinct! 
Despite the vast number of ways that the selecting process can be performed, we’ve created a standardized process that can be faithfully replicated at any scale to select for amazing genetics. If you’d like to work with us to conduct an upcoming pheno-hunt, please contact us for additional information. If you’re not sure we’re a good fit for your projects, we wanted to share a helpful checklist derived from our standardized pheno-hunt protocols to help you stay on track as you plan your own pheno-hunts. You can now download that checklist for free by clicking here

It’s been a long journey to identify and source appropriate genetics, plan your pheno-hunt, grow the plants and take extensive observations, select the winners, clone them, vet them and continue selecting. You finally have your new prized phenotypes. Now what?

The first and most important step is to preserve the unique genetics that create the phenotype you’ve selected for. This is usually done by selecting one or more mother plants from the cuttings of the original plant you selected. 

A mother plant is kept in a vegetative state for a long period of time and only used for taking new cuttings to propagate the genetics. The cuttings can then be cloned further and/or grown to produce flowers of your new amazing phenotype. 

Once you have mother(s) established, it’s usually prudent to organize a panel of test growers to cultivate your new phenotype in their own gardens. By growing your genetics in another environment, you can get a sense of how reproducible the phenotype that you selected for is in the hands of another grower. 

You may end up finding out that the genetics that you selected are actually capable of producing a wide range of phenotypes when grown in different conditions (e.g indoor vs. outdoor). The process of having your genetics “tested” by other growers can also identify any potential drawbacks inherent to cultivating your variety in an environment different from yours. This knowledge is essential if you plan to distribute your genetics later on.

One incredibly powerful tool that’s becoming an increasingly popular way to describe phenotypes and discover relationships between them is genome sequencing, or genetic variant analysis. Having the genome of your cultivars analyzed provides insights into the underlying factors that produce your prized phenotypes. You can use this information to predict other cultivars that have similar phenotypes, learn how much heterozygosity is present throughout the genome, identify how unique your cultivars are, and in contrast you can also identify how closely related your cultivars are to another cultivar.

To preserve your genetics indefinitely you’re eventually going to need to produce your own seeds. Don’t worry, this isn’t as difficult as it sounds and you’ve already done the hard part by selecting for winning genetics. The major caveat is that producing seeds involves sexual reproduction which by its very nature is going to alter the underlying genetics of your cultivar. However, there are a few techniques that can be used to preserve the genotype and phenotype of your prized cultivars. 
Selfing your cultivar (breeding it with itself) by inducing hermaphrodites is the more stringent approach as this won’t introduce any new genetic material into the resulting offspring. You’ll still have genetic variation introduced because of: 1) independent assortment of chromosomes during meiosis (production of pollen/ovules), and 2) homologous recombination (e.g. crossing-over) between the two different (heterozygous) copies of the chromosomes. If that doesn’t make sense, don’t worry, we’ll summarize it with less jargon below. 

Breeding cannabis seeds

Breeding cannabis seeds
The take-home point is that selfing will introduce less variation than back-crossing (breeding) with one of the original parental lines. However, there’s always a caveat that when you’re producing feminized seeds you’ll have to hope you don’t get increased frequency of hermaphrodites in the resulting seeds compared to conducting a dioecious cross with a male plant.
​In both cases, when you’re breeding you’ll need to continue to select for your prized phenotype in each new generation. Genetic testing can massively speed up this process and help you achieve a stable inbred line that yields consistent phenotypes (nearly 100% homozygous) much faster than relying on traditional methods.

Last but not least. Don’t forget to download your copy of The Official Pheno-Hunt Checklist derived from our standardized pheno-hunt protocols to help you stay on track as you plan your own pheno-hunts.

If you’d like to work with us to conduct an upcoming pheno-hunt, please contact us for additional information.

Happy hunting! ????​


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