Propagation 1 Final

Propagation

The reproduction of new plants from seeds and vegetative parts of a plant.

Methods of Propagation

Seeds, Cuttings, Grafting, Division, Layering, Tissue Culture.

Agriculture

The art and science of cultivating soil, growing crops, raising livestock, and preparing and distributing plant and animal products for human use.

Domestication

Selecting and adapting wild plants for human use.

Annuals

Plants that complete their entire life cycle in one year.

Biennials

Plants that complete their entire life cycle in two years.

Perennials

Plants that return year after year.

Mitosis vs Meiosis

Mitosis produces 2 identical diploid (2n) cells in 1 division; Meiosis produces 4 different haploid (n) cells in 2 divisions.

Homozygous

Having two identical alleles for a specific gene

Heterozygous

Having two different alleles for a specific trait.

Auxins

Plant hormone found in shoot/root tips; promotes cell division, stem/root growth, and rooting in cuttings; influences plant orientation to light and gravity.

Gravitropism

A plant's growth response to gravity: roots grow downward (positive), shoots grow upward (negative).

Gibberellins (GA)

Plant hormones that regulate seed germination, stem elongation, flowering, and fruit development.

Cytokinins (CK)

Plant hormones that stimulate cell division and adventitious shoot formation, especially in leaf cuttings.

Ethylene

A gaseous plant hormone that promotes fruit ripening, flower opening, and leaf aging (senescence).

Plant Embryo

The undeveloped baby plant within a seed or bud.

Cotyledon/Endosperm

The seed's embryonic leaf providing energy and nutrients to seedlings before photosynthesis begins.

Seed Coat

The outer protective layer of a seed.

Conditions for Germination

Viable seed, appropriate environment, and breaking dormancy.

Environmental Conditions for Germination

Water, proper temperature, oxygen, and appropriate light or darkness.

Dormancy

A state where seeds won't germinate even in suitable conditions.

Physical Dormancy

Seed coat prevents water absorption; requires scarification or stratification.

Chemical Dormancy

Inhibitory chemicals in fruit prevent germination.

Scarification

Altering the seed coat to allow water/gas in and trigger germination.

Stratification

Mimicking winter conditions (cold/moist) to break dormancy and induce germination.

Photodormancy

Germination depends on light or darkness based on plant species.

Epigeous Germination

Cotyledons emerge above ground.

Hypogeous Germination

Cotyledons remain below ground while true leaves emerge above.

True Leaves vs Cotyledons

Cotyledons provide stored energy until the true leaves form and photosynthesis begins.

Measuring Seed Germination

By percentage, speed/rate, and uniformity.

Damping Off

A fungal disease causing young seedlings to rot and die.

Types of Scarification

Mechanical, chemical, and heat treatment.

Seed Plug

A unit of soil and seed or seedling used for starting plants or lawns.

Stages of Plug Growth

Germination & radicle emergence, cotyledon expansion, true leaf development, and toning for transplant/shipping.

Asexual Propagation

Reproducing plants using vegetative parts (leaves, stems, roots, buds).

Advantages of Asexual Reproduction

Produces genetically identical clones; faster; ensures uniformity; useful for non-seeding plants

Totipotency

Each plant cell has the genetic potential to grow into a complete plant.

Mitosis (in Asexual Propagation)

Cell division method used in cloning plants.

Callus Tissue

A mass of cells forming at a wound site; aids healing and root development.

Adventitious Roots

roots that grow from non-root tissues, such as stems or leaves, rather than from the primary root system

Types of Adventitious Roots

Preformed roots develop naturally while attached; wound-induced roots form after cutting.

Stem Cuttings

Stem sections with a terminal or lateral bud used for propagation.

Deciduous Hardwood Cuttings

Taken from mature, woody dormant stems.

Herbaceous/Softwood Cuttings

Propagated in spring when there is lots of new growth of deciduous or evergreen species. Cut from late spring to late summer.

Conifer Cuttings

Dormant hardwood cuttings from conifers, usually with needles.

Leaf Cuttings

Use all or part of a leaf to propogate; the original leaf doesn't form the new plant.

Leaf-bud cuttings

a type of vegetative propagation involving a stem section with a single leaf, its petiole, and a dormant bud located in the leaf's axil (where the leaf joins the stem)

Root Cuttings

Root pieces from young plants, typically collected in late winter/early spring.

Proper Stem Cutting Technique

Cut below a node, remove lower leaves, ensure one node is below the medium.

3 Important Factors in Rooting Cuttings

Type of wood, stage of growth, and time of year collected.

what are Adventitious Buds/Shoots from Leaf Cuttings?

These form at the base of the leaf and develop into new plants.

Sources of Cutting Material must…

Must be disease-free, true-to-type, and in proper physiological condition.

Manipulation of Stock Plants include

Includes pruning for juvenility, girdling, etiolation, and banding to enhance rooting.

Rooting Hormones (PGRs)

Plant growth regulators that promote root development.

Good Propagation Media 

Must be disease free, well-draining, and hold adequate moisture.

What happens to herbaceous perennials in spring?

The tops of the plant turn dead, but the roots are still strong.

What are woody perennials?

Any plant with stems with bark; leaves fall off during dormancy.

What is the juvenile stage of growth also called?

Vegetative stage.

What is the adult stage of growth also called?

Reproductive stage; produces a flower.

What are the taxonomic stages?

Kingdom, Phylum, Class, Order, Family, Genus, Species.

What is a mnemonic for the taxonomic stages?

King Phillip Coughed On Fred’s Green Shoes.

What is phenotype?

External appearance.

What is genotype?

Genetic composition.

What do antigibberellins do?

Inhibit stem elongation, keeping plants shorter (dwarfing effect).

What is meiosis?

A special kind of cell division that results in sex cells for sexual reproduction.

What does edaphic refer to?

Any factor influenced by the soil or propagation medium.

What are microclimate conditions?

Environmental factors in the immediate vicinity of the plant during propagation.

What is intermittent misting?

A fine spray of water from a pressurized system that cools leaf surfaces.

What is fertigation?

Applying soluble fertilizer during irrigation of seedlings or rooted cuttings.

What is secondary dormancy?

When conditions were right and then became wrong, causing plants to revert.

What is seed priming?

Soaking the seed overnight.

What happens if you spray gibberellic acid on dwarf plants?

They become normal sized.

What are biotic factors?

Anything alive in the soil.

What is seeding in a field?

Planting directly into the ground and keeping it there.

What is seeding in a field nursery?

Propagating and producing a plant in a temporary location before final sale.

What are advantages of asexual propagation?

Creates clones, uniform plants, faster, used to dwarf plants, used when plants don’t produce viable seeds.

What are NAA and IBA?

Synthetic auxins.

What are the steps in wounding response and root regeneration?

Wounding, callus/mitosis, adventitious root formation.

What is polarity in plants?

The plant’s natural orientation, similar to gravity.

How do you select material for hardwood cuttings?

Should be taken from dormant material, pathogen free, vigorous, firm, absence of buds.

How do you select material for hardwood cuttings?

Should be taken from dormant material, pathogen-free, vigorous, firm, absence of buds.

Why would you reduce the leaf area  on semi-hardwood cuttings?

to minimize surface area. Which reduces water loss. 

leaf/bud cuttings versus leaf cuttings

leaf-bud cuttings include a leaf blade, petiole, and a short piece of the stem w/ bud attached.

What’s the first nursery to have been established in the U.S. and when/where was it founded? The Linnaean Nursery, Flushing, NY, 1737

Who invented the horse drawn seed drill in 1701?

Jethro Till

This person experimented with pea plants, learning how traits were passed from one generation to the next.

Gregor Mendel.

True or False. Juvenile leaves are identical to mature leaves.

False

Meiosis

results in 4 different haploid cells.

Mitosis

has only 1 cell division.

This occurs when one side of a plant has greater cell division due to a response to sunlight.

Phototropism

This hormone is responsible for gravitropism

auxin

This PGR is used to dwarf a plant by inhibiting stem elongation

Antigibberellin

This hormone can be used to ripen fruit that has been harvested prematurely

Ethylene

Why can’t you stick a stem cutting upside down

Polarity

This is the stress adaptation process that occurs as a cutting is weaned from a high to low relative humidity environment

hardening off

What is a phenotype

Physical traits

What is genotype?

The genetic traits

The six ways you can vegetatively propagate plants

cuttings, division, grafting, budding, division, and tissue culture.

Three parameters of measuring seed germination

Germination speed, percentage, and vigor

5 phases of mitosis -

prophase, prometaphase metaphase, anaphase, and telophase.