Test 2 Intro to Horticulture

Grafting definition

Union of root system with shoot system so they grow as one composite plant

Grafting vs. budding

Budding is a form of grafting in which the scion starts out as a single bud

Benefits of rootstock

Disease resistance, pest resistance, cold and heat tolerance, control size and yield

(bonus) Steps of the formation of the graft union

Align vascular cambium layers, wound response, callus bridge formation, wound-repair xylem and phloem, production of secondary xylem and phloem

Give two reasons why we might graft or bud

Only way to clone, provide more resistant roots to a plant

Grafting compatibility: does NOT work:

between families, usually between genera

Grafting compatibility: DOES work:

between species, w/in species and between cultivars

Disadvantages of grafting/budding

Incompatibility, skilled labor

Symptoms of transplant shock

Part or whole plant wilting or death

Transplanting container rules

1-2 or 2-4 inches larger than current root ball, drainage holes

Taxonomy

Identification, classification, and nomenclature

Father of botany

Theophrastus

Theophrastus

Father of botany

Father of taxonomy

Carl Linnaeus

Carl Linnaeus

Father of taxonomy

Give 2 reasons why common names are problematic

Multiple for same, same for multiple

Scientific binomial name written out as in exam

Genus species

Written out as in exam: Scientific binomial name with variety

Genus species var. variety

Written out as in exam: Scientific binomial name with cultivar

Genus species 'Cultivar'

Order ending

-ales

Family ending

-aceae

Cross-pollination

Pollination on different plants

Meiosis is...

The basis of genetic diversity and variation

Parts of pollen grain

Tube cell and generative cell

What does the tube cell do?

Form pollen tube that generative cell goes down

What does the generative cell do?

Releases two sperm nuclei

What about them two sperm nuclei?

One fertilizes the egg and the other fuses with two polar nuclei to form endosperm

At what stage of seed development are the seeds mature?

stage 2

Stage 2 of seed development is when...

seeds mature

What happens in stage 1 of seed development

Increase in seed size due to cell division

What happens in stage 3 of seed development

Maturation drying

Recalcitrant seeds do/don't tolerate maturation drying and are shed at stage ____

don't, 2

Orthodox seeds do/don't tolerate maturation drying

do

Quiescent seeds

environmentally needy

Conditions for germination:

viable seed, correct environmental conditions, overcome dormancy

Ecological advantage of dormancy

will attempt germination in best conditions for it

Physical dormancy

Seed coat impermeable to water

Physical dormancy is overcome by

mechanical and hot water scarification

Why are hormones important?

regulate everything

Hormones are...

naturally-occurring molecules found in low concentrations

Endogenous

made by plant

Hormones that are made by the plant are called...

endogenous

Plant growth regulators (PGRs) are...

externally applied

Example of how we use PGRs in horticulture:

rooting powder to get root formation in cuttings

Auxins are synthesized in

shoots and leaves

Method of transport in auxins

Polar, downward movement

One main purpose of auxin

Stimulate root formation

Antagonistic relationship of auxin

Control apical dominance with cytokinin

One main purpose of cytokinin

stimulate shoot growth and development

One internal function of gibberellins

Control plant height

One commercial application of gibberellins

Increase fruit size of seedless grapes

One function of strigalactones

Promote associations with arbuscular mycorrhizal fungi

Plant propagation definition

The purposeful act of reproducing plants and retaining unique qualities

A successful propagation method is one that...

Transmits all desirable characteristics

Pathways of plant propagation

Sexual, asexual

Sexual propagation is AKA

seed

Asexual propagation can be done through...

cuttings, grafting, budding

Totipotency

One plant cell has the blueprint to reproduce an entire plant

Most important type of cuttings

stem

A root cutting will have to make...

adventitious shoots

A leaf cutting will have to make...

adventitious roots and shoots

A stem cutting will have to make...

adventitious roots

Herbaceous definition

non-woody

Auxins stimulate ____ growth

root

Cytokinins stimulate ____ growth

shoot

Asexual propagation is AKA

vegetative or clonal propagation

Vegetative or clonal propagation DEFINITION

Producing new plant vegetatively, not sexually

Bananas are propagated by...

Suckers/pups/shoots

Strawberries are propagated by

stolons

Layering involves...

inducing roots on stem while still attached to parent plant

Air layering steps

Girdle stem, rooting hormone, moist media, wrap, foil

Why is layering successful?

continuous nutrient supply, no water stress

Two disadvantages of air layering

Labor intensive, small quantity

An advantage of air layering

Result in fairly large plant to begin with

Division

Forceful sectioning

Separation

Natural sectioning

Monceau

shoot regeneration from callus

Schleiden and schwann

cell theory

Vochting

Experimental totipotency

White

virus eradication in root tip

ball

shoot regeneration from root tip

limasset and cornuet

absence of virus in shoot and root tips

micropropagation stages:

plant selection and prep, establishment, shoot multiplication, root formation, acclimatization

Advantage of micropropagation

large number of plants in small space

DISadvantage of micropropagation

expensive