HORT 260 EXAM 1

SOT january-feb 6

IPPS

International Plant Propagators Society

origins of horticulture date back to

10,000 years ago

how did the Greeks and Romans practice hort?

root cuttings, air layering, grafting, ornamental gardening

in the Medieval age how did they practice hort?

estates, castles, and walled gardens

Carolus Linnaeus

binomial nomenclature

what is binomial nomenclature?

a system of naming species (genus/species)

Bartram’s Garden

1728, USA’s first botanic garden

Linnaeus said what about Bartram?

That he was the greatest natural botanist in the world

Lyman Estate

the oldest surviving greenhouse in the USA

herbals

described and illustrated medicinal plants

What was the main hort observation during the renaissance?

plant morphology and behavior/growth

Morrill Act

Act of congress in 1862 that established land grant universities for scientific study

Name four advancements of PP during the 20th century

Intermitttent mist/fog systems, PGR, Sanitation/pest control, and micropropagation techniques.

ASHS journal

American society for horticultural science

what is the first necessary step in the food chain?

seeds

What are the fastest growing segments of horticulture in the recent years?

floral and nursery industries

which endogenous growth regulator was a major milestone?

IAA (indoleacetic acid)

IAA is part of what?

auxins!!

what does IAA do ?

root and shoot initiation

methodology used to pp depends on what ?

whether a plant desires to be genetically identical to the original

seed production is a major part of which PP industries?

veggie transplants, bedding plants, nurseries

Name a few asexual propagation techniques

division, stem cuttings, root cuttings, leaf cuttings, budding, grafting

what is grafting?

placing one portion of a plant into or on a portion of another plant in a way that they unite and grow together

what is air layering?

a method of propagating new plants from stems still attached to the parent plant

callous tissue is

undifferentiated, actively dividing parenchyma cells. might produce adventitious root or shoot.

totipotency

cells contain all the genetic material to reproduce all tissues and functions of original organism.

a semi-permeable barrier

regulates movement of chemicals in and out of the cell. site of synthesis of cellulose

cellulose

most abundant biopolymer on earth. main constitute of plant cell walls.

name 4 things the cell wall does

gives shape and structure. thickness imparts the function of the cell. reduces water loss. prevents cell rupture due to TP.

turgor pressure

force exerted by stored water against the cell wall

primary cell wall is made of what 3 things

cellulose, hemicellulose, pectin

middle lamella

glue that holds two cells together, high in pectin levels.

pectin

a structural acid contained in primary lamella and cell walls, binding agent

plasmodesmata

connects cells and their cytoplasm

meristematic cells are

actively dividing

why do plants have all the same cells but differ in shape/size?

growth and morphology

4 cell types

meristematic, parenchyma, collenchyma, sclerenchyma

parenchyma cells

meristematic, thin primary cell walls, nuclei/protoplast, undifferentiated, resume meristematic act.

collenchyma cells

dedifferentiation, structural support, thick secondary cell walls, nuclei/protoplast, resume meristematic act.

sclerenchyma cells

mechanical support, water conduction, major plant organs, thick lignified secondary cell walls, don’t dedifferentiate or resume meristematic act.

tissues are

groups of cells to perform a similar function. form organs.

Epidermal tissue

outer layer of stems, roots, and leaves

what does the epidermis do

regulates water uptake/loss and gas exchange

Ground tissue

makes up the bulk mass of the plant

what does ground tissue do

structure, place for photosynthesis

what does vascular tissue do

transportation

what is vascular tissue

xylem and phloem

xylem is made of what

vessels and tracheids

phloem is made of what

sieve cells and companion cells

where is ground tissue found?

stems, roots, leaves

phloem transports

sugar and compounds downwards

xylem transports

water, minerals, hormones upwards

what is meristematic tissue?

cells that actively divide to produce growth (actively dividing cells)

where is meristematic tissue

tips of shoots/roots, the cambium of trees

what is apical dominance?

when the shoot tip suppresses the growth of axillary buds

what is the apical meristem?

groups of cells in the roots and shoot tips that are capable of cell division

what is the meristematic cambium

the vascular cambium of trees, a secondary meristem

what are organs?

a group of tissues that act together to serve a specific function

what is the shoot apical meristem?

produces cells that divide and enlarge

cells formed by the SAM will differentiate into

pith, leaves, buds, vase tissue, epidermis, flowers

name five functions of the stem

moves water/nutrients, photosynthesis, provides structure/flexibility, energy/water storage, hormones

vascular bundles do what

move water/ sugar/ nutrients/ hormones and provide support

where is secondary stem thickening seen?

woody plants

where is the vascular cambium

in between the vascular bundle, xylem, and phloem

in order from in to out, list the parts of a woody stem

wood, xylem, vascular cambium, phloem, bark

cotyledons

first leaves by germinating seed, contain store of food

monocot/dicot venation

parallel/netted

name three leaf functions

solar energy, photosynthesis, gas exchange

name four root functions

water/nutrient absorption, energy storage, anchoring/stability, production of hormones

root hairs

tubular extension of epidermis, increasing surface area

what is the difference between a taproot and fibrous root system?

a taproot is a singular root extending down, fibrous roots are secondary and spread all directions

photoperiodism

impact of light on a flower and seed production

long day vs short day plant

LDP flowers when exposed to a long photoperiod and short dark, SDP flowers when exposed to a long dark period and short photoperiod

what is a phytochrome?

a light sensitive pigment where quality of light changes form of Pr(inactive) and Pfr (active)

nurserymen

covering stock plants to promote stock plant shoots to grow w little or no light

blanching

velcro applied to green tissue for several weeks; tissue specific etiolation

blue light causes what

stomates to open

transpiration

water loss from a plant, mostly through stomata

cohesion and adhesion

move water through system

what are the four environment factors that drive transpiration water movement in plants

temperature, solar radiation, wind, and relative humidity

warmer temperature

increases transpiration rate

solar radiation will

increase transpiration rate

less wind

decreases transpiration rate

less humidity

increases transpiration rate

vapor pressure gradient

the difference in vapor pressure between the internal spaces in the leaf and the atmosphere around it. the driving force of transpiration.

cuticle thickness does what

decreases transpiration, but reduces growth.

stomatal aperture

stomates use turgor pressure, phytochrome, and blue light for when and how much they open.

leaf water potential equation

osmotic pot + turgor pressure + matric pot + gravimetric pot

well watered plants have a water potential of what?

0-1 MPa

water relations for successful stem propagation

place cuttings under mist, high humidity chamber, cooler until being stuck in soil

at what time of day should you take cuttings?

EARLY because they have less negative water potential, turgid cells, and lower temperature

what are sweat chambers good for

“hardening off” stem cuttings

what are some practical ways to control light?

shade cloth, color of plastic

practical ways to control temperature

ventilate, heaters, circulation, evaporative cooling

practical ways to control wind

fans, curtain

practical ways to control humidity

mist system, watering porous material, putting plants close together, evaporative cooling

what is evaporative cooling?

using heat in the air to evaporate water off plants or other surfaces

mist vs fog

water droplet size in mist is larger, fog smaller

before mist systems, cuttings and seeds were what?

syringed

cultural benefits of misting systems

larger cuttings can be roots, taken in softer stages, and more uniform