Welcome and I m so glad to see you guys today. Thank you for inviting me. I m sorry to use this title but don t you think Propagation is kind of boring? And truly, when we are talking about propagation we are talking about reproduction. And reproduction starts with sex right? 1
So I m going to start with basics so we are all on the same page. We all know that sex starts with a mommy and a daddy. And if considered on a strictly basic level, the reason they have sex is to have children in order to continue the species. 2
But if the mommy and daddy are too closely related like brother and sister or even first cousins then there will be less genetic diversity and the offspring will be less viable, weaker, and mutations are more likely to occur especially if close relatives repeatedly reproduce. Hence all the West VA jokes. 3
So lets take this to the plant world. And we start with the history of plants through time. Plants began as one celled organisms that gathered together and something called blue-green algae was formed. This reproduced by the cells dividing but this basically created more cells that were clones of the first. 4
Then the mosses arose in the historic record. Mosses do have male parts and female parts. The male cells must swim through a water layer to reach the female parts. Then the plant will produce another organism which you see here. These organs produce spores which are spread to create new moss plants. However, this is a plant fertilizing itself which means it is the same genetic material and it relies on moisture and chance to happen. 5
Next come the ferns. Ferns are really just advanced mosses with vascular systems. The fern will produce spores which is what you see here in this cinnamon fern on the left. Other ferns will grow these on the bottoms of the fronds. If these spores fall or are blown into a suitable spot, they will grow into a gametophyte which is a sexual intermediate plant. This intermediate plant will then grow male and female parts. The male cells will then swim to the female and if they meet, they will then produce a new fern from the gametophyte. Still pretty iffy, needs water and still basically the same genetic material. 6
The next big advance is the gymnosperms. These are the conifers. Now conifers have two types of cones. Male cones and female cones. And what was it that made the conifer so special? It s the first sexual reproduction with genes from two different contributors. And they do this by producing pollen. And for those of you who have lived at the beach, you know it can be a lot of pollen. Anyone know why so much? The pollen is spread by the wind. And those trees need a lot of it in the hopes that some might find its way to another plant of the same species. But the tree also doesn t really want the pollen to land on its own female cones so it has several methods to prevent this. Either the pollen is released at a different time from the opening of the female cones. Or maybe they are in different places on the tree. But there is still a pretty large element of chance in this type of reproduction. Hopefully, the wind will carry enough pollen to a tree of the appropriate species and it has to land in the right spot. And the tree has to produce a huge quantity of pollen in order to ensure something gets where it needs to be. And this creates a large resource drain on the tree to produce so many high protein 7
particles. 7
The next big advance is the gymnosperms. These are the conifers. Now conifers have two types of cones. Male cones and female cones. And what was it that made the conifer so special? It s the first sexual reproduction with genes from two different contributors. And they do this by producing pollen. And for those of you who have lived at the beach, you know it can be a lot of pollen. Anyone know why so much? The pollen is spread by the wind. And those trees need a lot of it in the hopes that some might find its way to another plant of the same species. But the tree also doesn t really want the pollen to land on its own female cones so it has several methods to prevent this. Either the pollen is released at a different time from the opening of the female cones. Or maybe they are in different places on the tree. But there is still a pretty large element of chance in this type of reproduction. Hopefully, the wind will carry enough pollen to a tree of the appropriate species and it has to land in the right spot. And the tree has to produce a huge quantity of pollen in order to ensure something gets where it needs to be. And this creates a large resource drain on the tree to produce so many high protein 8
particles. 8
So obviously what was needed was a surer way to get pollen from one plant to another of the same species. And that brings us to the Angiosperms- plants with real flowers. The first flowers were probably pretty simple. But over time they became more elaborate and intricately designed with only one purpose- to attract something that would pick up the pollen and take it to another plant. And in the process avoid being fertilized by its own pollen. 9
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When looking at flowers, there are a number of ways they are designed. There are male and female plants that have male flowers on one plant and female flowers on another plant. (ilex, ginkgo, kiwis). There are plants that have male and female flowers in separate flowers on the same plant (Squash). And there are plants with both male and female parts in each flower like this hibiscus. 11
And then there are some flowers that are pretty surprising because they aren t really flowers at all. Dogwood, where are the flowers on this dogwood. Here s a modern hydrangea. Where are the flowers? Here s a modern lace cap. Both of these were massively hybridized in order to take advantage of the sterile flowered pompoms or the real flowers. This is an antique hydrangea from before hybridization took place. You can see some pompoms and some lacecaps on the same plant. 12
There are a number of possibilities here. Birds, Bees, Moths, butterflies, flies, beetles, and bats. 13
Now I said there was only one purpose for flowers and that is to get something to come grab the pollen and take it to another flower of the same type but different plant so its genetic material moves. New research is showing that flowers do more than just look good. The design is such that the pollinatore must pick up or drop off pollen. Nectar is a reward to get the critter there. Now research has shown that many plants actually produce a small amount of caffeine in their nectar as well. Free coffee and donuts Hello. Other plants have polllen with an electrical charge and the insects like bees are the opposite charge so they are attracted. Tomatoes and blueberries must be vibrated for theme to drop pollen. But what if the pollinator comes repeatedly to a flower that has already had its nectar consumed. We now know that the electrical charge changes over time so insects don t repeat visit or the color changes, or they close up. 14
But even with these specialties, pollination is still a bit chancy. A critter has to just happen by at the right time, happen to get pollen on itself, and then happen to take the pollen to another plant of the right type. So plants began to specialize. First they produced nectar. For the insects, pollen provides protein for cell construction and nectar provides sugar for energy. But then flower designs started to change in order to specialize for a specific pollinator. 15
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The reason I have gone over all this, not only because it is so interesting, but is because after the plant is pollinated, it produces seeds and that is really what we are interested in in this class. You can produce new plants by planting the seeds. Seeds have four requirements, water, light, oxygen, and temperature, of which amounts needed are determined by the plant variety. 17
OK that s it for sexual reproduction. Now lets move on to asexual reproduction. 18
For a plant there are still advantages by producing new plants through asexual reproduction. These are clones, if you will, of the original plant. It makes a larger plant which allows it to gather more moisture, nutrients, etc. If some of the plant is killed for some reason, its more likely that some will survive. If it is attacked by insects, then there is more likelihood that some of the plant will still be healthy to support the extra stress. And for us humans, it provides us with another way to get more plants. And I want to take this moment to add if you have a named plant, it must be propagated by one of these methods rather than through seeds. Only a clone of that original plant has every attribute of the parent. If seeds are gathered, then likely they won t be exactly true to the parent. 19
Terminal bud- the bud at the very end of the branch Lateral Bud- a bud not at the tip of the branch Node- the area where the bud originates on a branch Internode- area between the nodes Stem- the main support (trunk) Leaf- food producing organ Petiole- the small stem that holds the leaf onto the stem Root- the underground structure that supports the plant, stores food, and collects water and nutrients Root Cap- The covering of cells on the tips of the roots that protect the apical meristem 20
Division is the first method we will discuss. This is a matter of digging up the plant and cutting them apart so there are tops and roots together. 21
Small plants grow out from the Mother plant. Cut those off and plant them. They will make a new plant. 22
Place a leaf into sterile soil and it will grow a new plant. Some will grow at the petiole and some will grow from cut veins 23
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Stem cuttings are done with a lot of different plants. There are four different types of cuttings that can be done. Herbaceous is done on herbaceous (nonwoody) plants. Softwood are collected from woody plants when the new growth has just finished growing. Semi-hard wood the new growth wood is just starting to develop bark. Hardwood is this years wood that is at the end of the season so it has fully formed bark. Different plants do better with different types of cuttings. Look it up to find which plant wants which. 25
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