Plant Propagation – Asexual Propagation Mr. Wilson Uintah High School Agricultural Sciences
Reproducing plant by means other than seed. • Asexual Reproduction: • The reproduction of a plant without the uniting of a pollen and ovule. • Asexual reproduction is often referred to as vegetative propagation since no seed is involved in the formation of the new plant. • It is known as a clone. • Leaves, stems or roots may be used to grow a new plant. • *Produces a genetically identical plant. What is asexual propagation?
The only way to reproduce certain varieties. • Assures that certain characteristics from the parent plant are carried to the next generation. • Quicker than other methods. • Less expensive than other methods. What are the reasons for producing plant asexually?
Cuttings - using the stems and leaves to reproduce plant • Division/Separation - pulling or cutting apart groups of plants to make new individuals • Layering - producing a plant from a part of a plant while that part is still on the parent plant • Grafting & Budding - connecting two pieces of living plant material together to form a single plant. What are the types of asexual propagation?
A section of stem with leaves attached. • Should have three to four leaves for best rooting. Stem CuttingsNumerous plant species are propagated by stem cuttings. Some can be taken at any time of the year, but stem cuttings of many woody plants must be taken in the fall or in the dormant season. What is a stem cutting?
How to make Stem Cuttings • Tools • Sharp knife, single edge razor, & disinfectant • Remove all flowers & buds • Plant needs to utilize energy for root development • Apply Rooting Hormone • Use proper soil medium
Normally include the terminal bud • Stem 2-4” is used • Cut made just below the node • Remove lower leaves • Apply rooting hormone • Insert in media deep enough to be self supporting • 1 node must be below the surface of the media for root growth to occur Stem Tip Cuttings
Use middle portion of stem behind the tip cuttings, 2-4” sections are needed • Remove lower leaves • Cut just above a node on each end • Handle as a tip cutting • Position the cutting with the right end up • Axial buds are always on the tops of the leaves Stem Section Cuttings
Cane Cuttings For plants with cane like stemsCut cane-like stems into sections containing one or two eyes, or nodes. Dust ends with fungicide or activated charcoal. Allow to dry several hours. Lay horizontally with about half of the cutting below the media surface, eye facing upward. Cane cuttings are usually potted when roots and new shoots appear but new shoots from dracaena and croton are often cut off and re-rooted in sand. Cane Cuttings
Heel Cuttings • Used on woody stemmed plants • Shield shaped cut made ½ way through the wood around the leaf & axial bud • Apply rooting hormone • Insert into media
Single-Eye Cuttings • Used on plants with alternating leaves • Cut ½ “ above & below the node • Apply rooting hormone • Place vertically or horizontally
Double-Eye Cutting • Used on plants with opposite leaves • Used when stock material is limited • Select single node • Cut ½” above & below the node • Apply rooting hormone • Place vertically
Leaf CuttingsLeaf cuttings are used almost exclusively for a few indoor plants. Leaves of most plants will either produce a few roots but no plant, or just decay. Leaf Cuttings Whole Leaf with PetioleDetach the leaf and up to 1 1/2 inches of petiole. Insert the lower end of the petiole into the medium. One or more new plants will form at the base of the petiole. The leaf may be severed from the new plants when they have their own roots, and the petiole reused. Whole Leaf with Petiole Whole Leaf without Petiole Whole Leaf without PetioleThis is used for plants with sessile leaves. Insert the cutting vertically into the medium. A new plant will form from the axillary bud. The leaf may be removed when the new plant has its own roots.
Leaf Cuttings • Made from leaf with the petiole cut to less then ½” • Make a clean cut • Apply rooting hormone • Place vertically in rooting media
Leaf Petiole Cuttings • Used on a leaf with ½” – 1 ½” long petiole • Place vertically in media • Several plants will develop from the base of the petiole
Split Vein Other leaf cuttings Split VeinDetach a leaf from the stock plant. Slit its veins on the lower leaf surface. Lay the cutting, lower side down, on the medium. New plants will form at each cut. If the leaf tends to curl up, hold it in place by covering the margins with the rooting medium. Leaf Section Leaf SectionsThis method is frequently used with snake plant and fibrous rooted begonias. Cut begonia leaves into wedges with at least one vein. Lay leaves flat on the medium. A new plant will arise at the vein. Cut snake plant leaves into 2-inch sections. Consistently make the lower cut slanted and the upper cut straight so you can tell which is the top. Insert the cutting vertically. Roots will form fairly soon, and eventually a new plant will appear at the base of the cutting. These and other succulent cuttings will rot if kept too moist.
Leaves such as begonia are cut into wedges, each containing at least 1 vein • Make the cut in a wedge shape with the bottom being the point • Done so you can tell the top from the bottom • Sections are then placed in media • New plants will form where the vein is in contact with the media Leaf Section Cuttings
Used with large leaf plants such as begonias • Remove leaf from stock plant • Slit veins on the bottom surface of the leaf • Place the leaf on rooting media with the slits down • A new plant will form at each of the slits Split-Vein Cuttings
Plants with large roots Root Cuttings Root CuttingsRoot cuttings are usually taken from 2 to 3 year old plants during their dormant season when they have a large carbohydrate supply. Root cuttings of some species produce new shoots, which then form their own root systems, while root cuttings of other plants develop root systems before producing new shoots. Plants with Large RootsMake a straight top cut. Make a slanted cut 2 to 6 inches below the first cut. Store about 3 weeks in moist sawdust, peat moss, or sand at 40oF. Remove from storage. Insert the cutting vertically with the top approximately level with the surface of the rooting medium. This method is often used outdoors.
Use plants that are 2 -3 years old • Make cuttings when plant is dormant • They will have larger supplies of carbohydrates • Top cut is straight & bottom cut is slanted • Plants with large roots • Use section 4-6 inches long • Plants with small roots • Use section 1-2 inches long Root Cuttings
Store cutting 2-3 weeks in moist peat moss or sand at a temperature of 40 degrees • Large roots • Plant vertically with the slant cut down • Top should be flush with surface of media • Small roots • Place cutting horizontally ½” below media surface Root Cuttings
Small Root Cuttings Plants with small roots Plants with Small RootsTake 1 to 2 inch sections of roots. Insert the cuttings horizontally about 1/2 inch below the medium surface. This method is usually used indoors or in a hotbed.
Eye Cuttings Single EyeThe eye refers to the node. This is used for plants with alternate leaves when space or stock material are limited. Cut the stem about 1/2-inch above and 1/2-inch below a node. Place cutting horizontally or vertically in the medium. Double EyeThis is used for plants with opposite leaves when space or stock material is limited. Cut the stem about 1/2-inch above and 1/2-inch below the same node. Insert the cutting vertically in the medium with the node just touching the surface.
Heel Cutting Heel CuttingThis method uses stock material with woody stems efficiently. Make a shield-shaped cut about halfway through the wood around a leaf and axial bud. Insert the shield horizontally into the medium.
To induce root formation • To increase number of roots • To prevent root-rot. Why is rooting hormone used?
To maximize growth. Most cuttings are planted in small pots or flats. After they develop enough roots they are transplanted into larger pots. Why do people transplant cuttings?
After cuttings have developed a mass of roots they are ready to be transplanted. Great care should be used when removing the plants from the medium. • Carefully remove the cutting. Grasp the top of the cutting with your left hand, slide the right hand under the cutting, and gently lift it from the medium. • If there is excessive amounts of medium, gently shake the cutting. • Plant it in the new pot. Make sure it is no deeper than it was planted in the propagation medium. If they are planted too deep, tender stem tissue is exposed to any diseases in the medium. • Water thoroughly. How do you properly transplant cuttings?
Moisture -- Cuttings have no roots and must be kept moist until roots form. • Above Ground Temperature – Varies with crop • Below Ground Temperature -- Bottom heat 70 - 80 degrees according to crop • Time What is the proper rooting environment?
Separation is a method of propagation that occurs naturally in which reproductive organs of a plant detach from the parent plant to become new plants. • They are bulbs or corms. • Some plants are easily propagated by separating the main part into smaller parts • Plants with rooted crowns are separated by cutting or pulling them apart • Plant the clumps separately What is separation?
Division is a method of propagation requiring the cutting and dividing of plants. • Rhizomes, tubers, and tuberous roots are used in propagation by division. What is division?
Plant Propagation – Layering MR. Wilson Uintah High School
Reproducing a plant from a part of the plant while that part is still connected to the parent plant. • In many plants stems will develop roots in any area in contact with the medium while still attached to the parent plant • Advantages • Plant doesn’t experience water stress • Sufficient carbohydrates are supplied to the developing plant What is layering?
Where a branch from a parent plant is bent to the ground where it is partially covered at one point in the soil. What is simple layering?
Common on: • Azaleas, rhododendrons, & other plants • A stem is bent to the ground & covered with medium • Wound the bottom side of the stem in the medium • The last 6-10” of stem is left exposed Simple Layering Colorado AgriScience
A portion of the stem may be buried until roots form; then the connection with parent plant can be broken. This called ground layering. Simple Layering
Simple Layering Colorado AgriScience
Common in Raspberries & Blackberries • Make a hole in the medium next to the parent plant • Place the tip of a shoot in the hole & cover it • The tip will grow down & then up • Roots will form at the bend • When the new tip appears above the medium it is ready for transplanting Tip Layering Colorado AgriScience
Tip Layering Colorado AgriScience
A part of the plant stem is girdled and then surrounded by a moist growing medium in some type of enclosure. Air LayeringAir layering is used to propagate some indoor plants with thick stems, or to rejuvenate them when they become leggy. Slit the stem just below a node. Pry the slit open with a toothpick. Surround the wound with wet unmilled sphagnum moss. Wrap plastic or foil around the sphagnum moss and tie in place. When roots pervade the moss, cut the plant off below the root ball. Examples: dumbcane, rubber tree. What is air layering?
Stem is girdled with 2 cuts 1” apart • Remove bark • Dust wound with rooting hormone & surrounded in damp sphagnum moss • Wrap plastic around moss & tie at both ends Air Layering Colorado AgriScience
In a few weeks roots will appear throughout the moss • Cut the stem just below the newly formed root ball • Plant the ball into a well drained potting medium Air Layering
A section of stem may be wounded and covered with moist peat and black plastic covering. After roots form, the stem can be detached and planted. This is called air layering. Air Layering Example