Plant Breeding Introduction

In the next few posts, I hope to begin to explain the art and science of plant breeding. Breeding plants creates new varieties or improves on old varieties. As a hobby anyone can try plant breeding. The crossing techniques (mixing male and female) is easy for many plants and you will get improvements in a couple generations if you choose traits that you see, flower color, plant size, etc. The home hobbyist does not have all the resources of modern plant breeders, but you can still work to improve your plants for your indoor grow area, and/or for your personal preferences.
Plant breeding has been done for 1000’s of years, so it is not rocket science. However, there are a lot of misinformed people when it comes to breeding plants. I have seen so many people buy a seed packet, grow them and get seeds from the plants and tell me their seeds are the same as the original one’s they bought, maybe even call them by the same brand name. Ya, right! Plant breeders spend years and lots of time to get pure breeding* plants. If you mate two hybrids* even though both plants look the same, (say short in height) they will have A LOT of different types of offspring (children), tall, medium and yes some short too, but all the seeds you made will NOT be the same. I hope the following posts will help if you are breeding your plants, and make you think about breeding if you are not. As always, you can send questions/comments to askthedoctor@htgsupply.com.

The art of plant breeding comes in knowing your crop, being curious and making observations.
To define plant breeding, it is the development of a plant cultivar that fits a specific environment and meets the needs of the grower. Plant breeding is applied evolution and applied genetics to effect some permanent genetic change.

One of my teachers in a plant breeding class had a saying,” Don’t get mired in mediocrity”. What this means is that if you are going to attempt to improve plants by breeding, you must be ruthless in which plants you choose to breed. Only the best of the very best can be chosen to start the next generation. Experienced plant breeders know it is not always simple to combine desired traits from one generation to the next; therefore, you can never risk introducing inferior traits in your breeding program. If you breed average plants, you will only get average plants as offspring. You need to pick and choose the best of the best plants to breed to have the greatest chance of getting improved plants. Each time you breed two plants is like dealing a hand of cards. You greatly increase you chance of having a wining hand if you only deal yourself face cards.
Of course, if you have a superior plant, you should consider cloning (see my article at http://htgsupply.com/images/articles/HTGSupply-Cuttings-November-2008.pdf). This is asexual reproduction where there is no mixing of male and female reproductive cells. Many commercial nurseries use a mother plant(s) to provide hundred’s of new cloned plants all that meet their growing needs, each plant exactly the same. The home grower can do the same. However, studies have shown that most plants tend to loose vigor and vitality after being cloned for many years. That is one reason why you always see new cultivars or varieties every few years. After many generations of cloning, plants just don’t pack the same potency or yield. The reasoning seems to be that individual cells of an organism keep track of time with their DNA. What this means is that although the cutting/cloned plant is starting small and getting big, like a juvenile becoming an adult, its cells are the age of the original plant. Older plants as a rule will have less vigor and lower yields.
You may remember the first cloned mammal “Dolly” the sheep… Did you know after ½ the normal life of a sheep she was euthanized (at age 6) due to a lung ailment common in older sheep. Sheep normally live to be 11-12. The 6 year old clone Dolly had arthritis and the body of a sheep suffering from old age. The moral is that eventually, even with cloning, you will need to mix DNA from male and female parts of a plant to reset the genetic clock. When plants under go sexual reproduction the DNA genetic clock is reset at zero, then you can restart cloning for a couple years once a superior plant is found again.

Read my post on How to Select the Right Plants to Breed, if you are serious about plant breeding.
Read my post on Breeding Techniques to see which one is right for you.

Good Growing!

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