Test 2 Flashcards
Annual-
Completes life cycle in one growing season
Germination– Vegitative Growth–Reproductive growth–Death
Biennial
Requires two growing seasons to complete lifecycle
Seed- Veg Growth one– Dormancy– Veg Growth 2– Reproductive Growth– Dead
Perennial-
Lives for more than two years(woody or herbaceous)
Seed– Veg Growth–Reproductive– Dormancy — Death but can go from dormant to Veg again.
Monocarp–
can live for many years but once it flowers it dies.
Germination– growth–dormancy–flowering– death
with a loop on growth and dormancy
What are the four main stages of maturation in plants?
Germination
Juvenility
Maturity
Senescence
Three main parts of a seed-
Embryo
Seed Coat( Testa)
Stored Energy
Describe the beginning and end of Germination-
Starts when seed absorbs water, Ends when the radicle emerges.
When does establishment begin and end-
Time from germination until seedling is independent and photosynthesizing
Environmental Requirements of Germination-
Adequate Moisture
Favorable Temperature (70-80)
Oxygen
Light
Radicle-
Hypocotyl-
Epicotyl-
Growing embryonic Root
Seedling stem between radicle and cotyledons
Seedling stem between cotyledons and first leaves
Describe the difference between Epigeal and hypogeal emergence-
(Epi- above,Hypo-BELOW) in epigeal the cotyledons emerge above the soil surface and the hypocotyl elongates.
In hypogeal the cotyledons stay below the surface and the hypocotyl does not elongate. only the Epicotly emerges. (All grasses)
In epigeal emergence in dicots what emerges from the soil first?
In Hypogeal emergence in dicots what emerges from the soil first?
- The hypocotyl emerges first.
2. The Epicotly Emerges
In hypogeal emergence in monocots what part of the seedling emerges first?
The coleorhiza
What does the juvenile stage of growth begin and end?
What are the four traits of Juvenility?
from germination and emergence to reproduction
Leaf form- different than mature
Growth Form- whiplike verticle shoots
Thorns
Leaf Retention-hold leaves during winter
Flower Induction-
Flower initiation-
Flower Development-
Initial chemical reaction that begins flowering(invisible)
Vegetative meristems change to flower meristems(microscope)
Visible development of flowers from bud to pollination
What four factors can induce the formation of flowers-
Self-induction(maturity)
Photo-induction(light)
Thermal Induction(vernilization req.)
Other-Factors (stress from drought or crowding) (light intensity)
What is photoperiodism-
short day-
Long day-
the response of a plant to the changes in day length
flower when light period is less than critical photo period (longer dark period)
flower when light period is more than critical photo-period (shorter dark period)
What is a phytochromes-
type of plant pigment that is colored blue. It is a light sensitive pigment. They control the ratio of Pred and Pfar red, and cause flowering
How are Pr and Pfr involved in flower induction-
Depending on the ratios they will cause flower induction
Ratio of Pr to Pfr increases SDP will flower
Pfr to Pr LDP will flower
Self Pollination -
Cross Pollination-
Pollen from the same plant fertilizes egg cells or genetically identical plant.
Pollen from genetically different plant fertilizes cells.
What is Parthenocarpy-
the growth of a fruit without fertilization, or after abortion of embryo, can be caused by growth regulation chemicals or specific environmental conditions.
Describe the process of Fruit Ripening.
What hormone is involved?
Sugars move from fruit to leaves, when fruit reaches full size ripening begins. ethylene gas is produced.
Fruit softens when pectic substances breakdown which strengthens cell walls and cements cells together,
color changes occur from breakdown of chlorophyll.
What is senescence? What changes in metabolism accompany senescence?
the aging and death of a plant or any of its parts.
Changes in metabolism include: Increased Respiration
Decreased photosynthesis
Breakdown of larger molecules into smaller ones
What is abscission-
in leaves where does abscission layer develop?
dropping of leaves, fruits, flowers or other plant parts.
where the petiole connects to the stem.
Dormancy-
When are plants dormant-
stage of development where growth slows or stops
occurs during periods not suitable for plant growth
winter dormancy- in cold areas
dryseason- in distinct wet and dry seasons
Why do needle shape leaves help evergreen trees survive the cold temperatures of winter?
they are adapted to minimize water loss due to smaller surface area during times when plants cant get water from frozen soil.
Three ways of breaking dormancy in seeds-
Vernilization- cold treatment
Stratification-storing moist seeds at temperatures near freezing for one or more months
Heat
Scarification- injuring the seed coat enough to allow water absorption and germination
What are plant horomones?
5 main groups?
natural substances produced by plants to control plant activities.
Auxins, Cytokinins, Gibberellians, Ethylene, Abscisic Acid.
Auxins-
Cause apical dominance, weed control
Cytokinins-
Promote cell division and tissue differentiation
Gibberellians
cell division and elongation , enzyme secretion
Ethylene-
Promotes fruit ripening
flower initiation
Abscisic Acid-
growth inhibitor, seed dormancy, stomotal closure
What are plant growth regulators-
3 ways synthetic growth retardants can be used in horticultural crops
influence the plant growth and development, can be hormones or non natural chemicals.
- florist crops to reduce growth
- hedges and lawns to slow growth
- Used to keep bedding plants compact.
- Improve color,
Climate-
Microclimate-
patterns of meteorological variation that develop over a large area over many years. Lat/long and season, mountians, oceans, etc.
weather conditions around a plant part, plant, or group of plants. buildings,ponds, land depression.
Five elements that make up climate-
Temperature Wind Precipitation Humidity Light