HS 200 Exam #2

Chance Seedling (Cultivar Type)

• Happened to grow by itself, no intervention

• Discovered, then developed

• No difference in botanical nomenclature between this and genetic mutations

Variant Plant

Variation of a straight species

Self-perpetuating

Characteristics that last thru generations; no humans involved to continue bringing out that specific trait

Come True from Seed (Species + Variety)

Grow up to look just like their parents

Genetic Mutation (Cultivar Type)

• Occurs on an individual plant in a particular location, causes a genetic change (in genotype)

• Discovered, then developed

• No difference in botanical nomenclature between this and chance seedlings

Hybrid (Cultivar Type)

Just developed, NOT discovered; someone had the idea first

Genotype vs Phenotype

DNA vs Appearance

Cuttings

Pieces of a plant that’s treated a certain way in order to grow the parts that are missing

Grafting

Surgically connect one genome to another; they don’t mesh, they continue to grow as their respective genotypes

Trees (Ornamental)

Exposed trunks with canopy

Allee (Ornamental)

Trees that run along both sides of a path/road/etc

Shrubs (Ornamental)

Multi-stemmed with branches to the ground

Vines (Ornamental)

Climbs on something vertical

Ground Covers (Ornamental)

Grows along the ground

Evergreen (Winter Appearance)

Plants that retain each year’s set of leaves for 3-5 years

Deciduous (Winter Appearance)

Loses all of its leaves every autumn (more born in spring)

Woody (Growth Kind)

Tissue comprised of hard, permanent tissue called wood

Herbaceous (Growth Kind)

Soft, tender, and succulent tissue that’s not permanent (cold often damages/destroys this tissue)

Tropical (Temp Tolerance)

Will not tolerate freezing temps and below, often injured by cold → ex: tomatoes, orchids

First Frost Free Date (FFFD)

The date after which the chance of frost decreases; Raleigh, April 15th

Last Frost Free Date (LFFD)

The date after which the chance of frost increases; Raleigh, Oct 31

Subtropical (Temp Tolerance)

Tolerate short periods of freezing but not for prolonged periods of time (hours) → ex: citrus

Temperate (Temp Tolerance)

Tolerate long periods of freezing and below for prolonged periods of time (days) → ex: apples, pears, cherries, oaks, maples, hollies

Annual (Length of Life)

• Any plant that lives for one growing season

• AKA “bedding plants”

• often killed by freezing temps

• plant 2-4 weeks after FFFD

Registered Trademark Names

• Name given to a plant that’s used to mark the plant or a group of similar plants → ex: apple

• Not a patent

• Little TM = trademark vs Little R = registered trademark

Scientific Cultivar Name vs Registered Trademark Name

• Cercis canadensis ‘JN2’

• “The Rising Sun(TM)” Redbud

Biennial

• Completes life cycle in two years

• First year = vegetative growth / second year = reproductive growth

• ex → Carrots and Queen Anne’s Lace, Daucus carota, are the same genus

• Foxglove, Digitalis

Perennial

• Plants that live for 3 years or more

• Woody vs herbaceous perennials

Volunteers

• Annuals that “appear” to act like perennials

• The plants idle but have set seed that is able to “overwinter” and germinate in the next season

Temperate Plant Hardiness Scale

• Based on the average annual minimum winter temperature

• Zone ratings = the lowest temps a plant can survive compared to the USDA chart

• Divided into 10 degree Fahrenheit zones

Roots (Vegetative Organ)

• Function: Absorption, anchorage, transportation of nutrients, storage

• #1 Absorbing organ; absorbing roots grow in the top foot of soil (12”)

• Not all roots do every function; certain ones for certain things

Primary Root

The first root to emerge from the seed

Secondary Root

Any root that emerges from a primary root or another secondary root

Adventitious Root

• Roots arising from abnormal places; roots coming from other adventitious roots

  • Some plants can have just adventitious roots and be perfectly fine

Tap Root

• Large swollen primary root “easily recognized” → carrot

• All ____ roots are primary roots but not all primary roots are ____ roots

Tuberous Root

• Large swollen secondary root

• Typically a storage organ → ex: sweet potatoes

Aerial Roots

• Roots often growing above ground

  • Often adventitious but not always

Epiphyte

• Plants that grow on other plants; 100% aerial roots

• Absorbing water/nutrition from the air, only using host plant as supportive structure; NOT PARASITIC

• Can accidentally kill other plants due to being overbearing and blocking the sun

• Ex: Orchids and Bald Cypress

Stems

Functions: Storage, transportation of nutrients, support, food production

Prostrate Stem

Stems that run along the ground

Stolon

• Type of Prostrate stem; runs along the ground and produces a plantlet at the tip

• Ex: Strawberries, spider plants → Chlorophytum comosum

Rhizome

• Type of Prostrate stem that runs below ground and produces a plantlet at the tip

• Ex: snake plant, iris, turf grass → Polygonatum odoratum ‘Variegatum’ = Variegated Solomon’s Seal → Seemannia nematanthodes ‘Evita’

Tuber Stem

• Large swollen underground stem

• ex: Irish (white) potato, tuberous begonia

  • Potatoes are the seeds themselves, the eyes can be cut with their own chunks and planted to grow more potatoes

Crown (Stem)

• Area where the stem meets the root

• Growing center of the plant, rosette of leaves (kind of a wagon wheel shape)

How do you distinguish roots from stems?

• Stems have nodes and internodes, but roots do not

• Roots can have adventitious buds, but it won’t have the set system

Nodes

Where leaves and buds come from on a stem

Internodes

The space between nodes

Leaves

• Leaf = blade + petiole

  • Functions: Food production, storage → #1 food producing organ

Simple Leaf

• One blade + petiole

• Bud is always the indicator of where the leaf begins

• Difference between simple and compound leaves is where the bud is located

Compound Leaf

Leaflets + petiole

Needle-Like Leaves

Found on some conifers, often in fascicles

Fascicle

The bundle of needles on a conifer tree → ex: loblolly pines have three needles per ____

Scale-Like Leaves

Found on some conifers

Awl-Like Leaves

Found on some conifers

What two factors causes plant failure and what increases due to this?

1. Poor light relations (sugar production)

2. Soil issues (water and nutrition)

3. Results in increased maintenance and plant replacement

What is necessary for plant growth?

• Water: Hydration, photosynthesis

• Nutrients: Health, compound

• Sugar (Glucose): Building blocks and fuel, “the 2 by 4 of growth”

  • Chemical Energy: Energy to grow

Dry Weight

• The measurement of the weight of the plant without any water in it

• 96% dry weight = sun, 4% dry weight = soil (both equally important)

Make-Up of Plants and Full Sun

• Made of tissues containing water, sugars, nutrients, and other compounds

  • Full sun = 6 hours of unimpeded sunlight at minimum, any less is partial

Absorption (Plant Growth Process)

• Primary function of the roots

• Water + nutrition absorbed differently

• Dependent on good soil building practices

• Needs water AND oxygen

Water Absorption

• Solute concentration (salts dissolved in solution)

• Osmosis occurs to maintain the same amount of solute concentration

  • Water absorption is a passive process within the plant; requires no use of energy

Osmosis

Diffusion of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration

Passive Reaction/Process

A reaction that requires no use of energy

Fertilizer Burn

The phenomenon in which too much fertilizer in the soil solution raises the solute concentration to the point where the water in the roots exits the roots and no new water can get into the plant, leading to the leaves drying out and dying.

How to fix fertilizer burn?

Add water in order to lower the solute concentration; unfortunately that also causes leaching of nutrients

Nutrient Absorption; CMT and AT

• Carrier Molecule Theory: Nutrient-specific molecules responsible for nutrient uptake

• We KNOW that these molecules must burn energy in order for the nutrients to be taken up

• Active Transport: Any biological process that requires an expenditure of energy

Translocation

• The movement of material from one location to another

• Water and nutrients → up → xylem

• Sugars → down and up → phloem

  • Vascular tissue, veins

Photosynthesis Equation

Chlorosis

Yellowing of the leaves that indicates a lack of chlorophyll

Chlorophyll

• Light sensitive; plants stimulated to produce chlorophyll when they’re in the light

• High light intensities will destroy chlorophyll, there’s often

• Dynamic molecule, breaks down over time if not replenished → needs to be produced regularly

What Factors Affect the Rate of Photosynthesis

• Light intensity

• Light duration

• Water availability

• Nutrient availabilty

• Chlorophyll concentration

• Temperature

Science of Foliage Color

Typically plants with multicolored or variegated leaves require higher light intensities than their green leafed straight species counterparts

Transpiration

• Process where water is absorbed by the roots, translocated through the plant, and evaporated through the leaves

  • 99% of the water absorbed into the plant exits thru transpiration, the other 1% is part of the ingredients of photosynthesis

• Transpiration and photosynthesis are positively connected to each other (buddies)

• Full cells are turgid; turgidity = amount of water in the cell

Factors that Affect the Rate of Transpiration

• Temperature

• Relative Humidity

• Air Movement

Stomata/Stomate

• Organelle of Transpiration (guard cell)

• When enough water, they open vs when not enough water, closes to cut off transpiration (photosynthesis rate also goes down)

  • Potassium is the nutrient that regulates the opening and closing; a lack of potassium also causes leaf margin burn

What Happens to Glucose?

• Stored

• Used as building blocks

• Biochemical synthesis; making hormones, proteins, etc.

• Burned for energy

Respiration

• Sugars are burned to yield chemical energy (ATP)

• Converting sun energy into food energy

• Temperature regulates the rate

• Glucose + oxygen = carbon dioxide + water + chemical energy

• Typically 3 photosynthetic units to 1 respiration unit

• Continues without sunlight, temp dictates how much respiration occurs during the night

• If plant is making equal to what it burns, it will die

Balance of Plant Growth

• Light if often the most limiting factor

• Anthocyanin: reds, purples, blues → function of glucose, so higher concentration when you have more sugar to spare

How do Plants Partition Sugar?

• Vegetative growth (roots, stems, leaves) and Reproductive growth (flowers, fruits, seeds)

• If there isn’t enough sugar for both, the default is vegetative growth to keep the plant alive

• If there isn’t enough for both but the plant thinks its in danger of dying, the sugar is then pushed to reproduction for continuation of the species and the plant will die after fruiting and flowering