Pollination and Fertilization

Pollination -- is the transfer of pollen from an anther* to a stigma*. Pollen is available when a mature anther splits open and releases the pollen. The pollen may be carried to the stigma in numerous ways; the most familiar are via wind and insects. In plant breeding, pollination must be controlled by YOU.
PRE-POLLINATION Before you collect pollen, you need to look at the stigma of the seed parent. It should have either a shinny substance on it that is sticky or a "hairy" surface. (you may need a magnifying lens) It is this substance or surface that catches the pollen, making fertilization possible. If the stigma is not mature (ready) you will not get fertilization (seeds) no matter how much pollen you apply.
When you pollinate you should know high temperatures and moist conditions are harmful to pollen. Try to pollinate when the humidity and temperature are low, usually in the beginning of the day/light cycle. Also, you can pollinate flowers on lower parts of the plant. Here there won’t be the high temperature from the lights. Remember the individual flower that is pollinated does not matter; it is the plant as a whole you want to judge when selecting.
MALES -- If it is physically possible, to help keep down unwanted pollination you should remove male plants, male flowers or male parts of flowers from the room where you will be doing pollination. With perfect flowers you will need to remove all anthers and the stem it sits on a filament (both together are called a stamen*) from the seed parent with tweezers. This gives you a chance to practice plucking the immature stamens on the seed parent since you may want to harvest whole stamens of the pollen parent and use them to pollinate the female.
Fertilization -- is combining male and female sex cells. After you put the pollen on the stigma, the pollen develops a tube which grows downward through the style and into the ovule. Fertilization occurs when the male and female sex cells unite in the ovule. Once fertilization occurs, development of the ovule begins which results in a seed. In other words, you can pollinate the plants (apply pollen to plants) but this does not guarantee fertilization (mixing of male and female DNA) If you are having problems getting seed formation, you may have a self incompatibility or inbreeding problem. I may write about this later, but if you are pollinating and having a problem with fertilization (no seeds) you can E-mail me at askthedoctor@htgsupply.com

POLLINATION with WIND pollinated flowers (plants with numerous small flowers) I often collect the pollen of a few male flowers from the SAME plant. I often snip the whole flower into the bag after I collect a few taps of pollen. For me, it is too much trouble to snip individual anthers with small flowers. Put the pollen in a paper bag and place that on the branch of the chosen female flower (see picture in this post). Be sure to hold the bag up so pollen does not spill out; make sure there are no fans running during pollination. I then give the bag a gentle shake every day for a few days. Make sure the branch can hold the extra weight of the bag, you may need to support the branch with string or tie-wire while the bag is on it. After a few days, take the bag off and see if the flower looks fertilized. Plants that are ANIMAL pollinated those that have a big showy flowers will need to be tested every day when the flowers are maturing to see if the pollen is being made A gentle tap will let you know if the yellow dust is being produced by the anthers. I like to collect the pollen in a small glass vial and apply it to the stigma with a brush. Don’t be afraid to experiment with different methods of pollination. Some people brush the actually anthers on the stigma, try using different types of brushes, different times of pollination (of the day and of stigma maturity) etc.
To sum up, there are three basic ways to pollinate, use a paper bag with pollen, use a small paint brush to apply the pollen powder to the anther, or if you like detail you can hold a stamen with tweezers and brush the anther across the stigma. Either method will deliver a lot of pollen. However you pollinate be careful and precise when you actually do the pollination. If the environment is cool and not too moist nature will take care of the rest.

POST POLLINATION -- After pollination, the seed parent should be protected from contamination by foreign pollen. This is why I often use a paper bag to pollinate; it keeps the good pollen in and the bad pollen out. If you have big flowers with large petals you can try closing the flower. In flowers like morning glories, petunias, or lilies, the petals can be closed around the reproductive organs with a piece of string, or rubber band. You can use whatever you want but you should NOT tear the petals. Some flowers, such as composite flowers, or those that produce multiple long flowers like the Coleus I have pictured in this post… cannot be closed. To protect them from unwanted pollen, you can cover the flower with a paper bag. You may be tempted to use a plastic bag, but I would not recommend it, with the plant giving off water due to photosynthesis a plastic bag over a branch will be good habitat for mold.
Each time you pollinate with a different pollen parent, be sure to first wash with alcohol or hydrogen peroxide the paint brush, tweezers, and anything which might have touched some pollen. Using water to wash your equipment is NOT good enough. This step is very important to prevent pollination of the seed parent with unwanted pollen that has adhered to the equipment. After you wash the instruments, make sure that they are dry or you will kill the pollen that you collect next.

It is very important to label the branch with and information about parents.

Btw, if you happen to be breeding outdoors, you will only need to keep the paper bag or whatever you use to keep unwanted pollen off the seed parent on for a week or so. The longer the better of course, but if rain or wind blows it off after a week most of the pollination should be done. Indoor or out, be sure to observe your plants each day after you pollinate so you can learn to tell as soon as possible if fertilization has occurred. Usually there will be signs that the flower has been fertilized like browning or wilting stigma. Compare this to unpollinated flowers and observe your success.

Good Growing!

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