Biology Of Horticulture Final Review

Front 1

Calculate GDD for a warm season crop when the min daily temp was 53 ̊F and the max daily temp was 85 ̊F. Just provide your number, do not include "GDD" with your answer.

Back 1

19.0 (with margin: 0.0)

Front 2

Calculate GDD for a warm season crop during a 25 day period when the min daily temp was 48 ̊F and the max daily temp was 90 ̊F. Do not include "GDD" just provide your number.

Back 2

450.0 (with margin: 0.0)

Front 3

hilling for cherries is optimal at 5 ̊C. It is 90% as effective at 2 and 7 ̊C. It is only 50% as effective at 0 and 10 ̊C. Above 15 C, plants lose chilling that has accumulated. 5 ̊C for 1 hour = 1 chill unit 2 ̊C and 7 ̊C for 1 hour = 0.9 chill units0 and 10 ̊C for 1 hour = 0.5 chill unitsUsing the information above for cherries (hypothetical information), how many chill units accumulated during the following 10-hour period? 3 hours at 5 ̊C, 3 hours at 7 ̊C, 2 hours at 10 ̊C, and 2 hours at 16 ̊C.

Back 3

4.7 (with margin: 0.0)

Front 4

Axial-basal patterning refers to which of the following?

Back 4

The plant establishing “up vs. down”

Front 5

Axial-basal patterning begins to be established how early in development?

Back 5

When the first division of the zygote occurs

Front 6

Why is it called double fertilization?

Back 6

Because two fertilization events happen; one to form the embryo and one to form the endosperm

Front 7

What is the easiest method of predicting growth and development?

Back 7

Chronology

Front 8

Double fertilization takes place inside the _______.

Back 8

Ovule and Ovary

Front 9

During which stage of seed development does the embryo develop its basic architecture?

Back 9

Histodifferentiation

Front 10

Which plant hormone is responsible for promoting maturation and preventing early germination?

Back 10

Abscisic acid

Front 11

If a seed is dormant simply because it is not receiving favorable conditions for germination, it is said to be ________.

Back 11

Quiescent

Front 12

Name the five mechanisms of exogenous or coat-imposed dormancy.

Back 12

Prevents water uptake

Mechanical Constraint

Interferes with Gas Exchange

Retains Inhibitors

Produces Inhibitors

Front 13

Using artificial means to weaken seedcoats to promote germination is called _______.

Back 13

Scarification

Front 14

The ability of cells to differentiate into any organ of the plant is called ________.

Back 14

Totipotency

Front 15

The L-I histogenic layer gives rise to __________.

Back 15

Epidermis

Front 16

__________ is an organizational pattern of cells present only during the growing season; at dormancy this organization disappears.

Back 16

Cytohistochemical zonation

Front 17

Position, timing, and number of successive primordia development determines ___________. This is how leaves are arranged and attached to stems.

Back 17

Phyllotaxy

Front 18

A plant that has an entire histogenic layer(s) mutated is referred to as a ___________ chimera.

Back 18

Periclinal

Front 19

Which species generally will produce more leaves in a season, fixed growth species or free growth?

Back 19

Free growth

Front 20

In a fixed growth species, when were the leaves during the current growing season formed?

Back 20

During the previous growing season

Front 21

Heterophyllous shoots can be found in ____________.

Back 21

Free growth species

Front 22

__________ is a phenomenon that affects a single shoot and only for a single growing season.

Back 22

Apical dominance

Front 23

I have a plant that has a mutation in the L-II histogenic layer that I want to propagate so I can give out plants at Thanksgiving. What would be an appropriate way to generate plants with that mutation?

Back 23

seeds.

Front 24

If I propagate using stem cuttings from a pear tree that is flowering, will the resulting tree be juvenile or adult?

Back 24

Adult

Front 25

All trees start out with ________ growth. This allows formation of the trunk.

Back 25

Excurrent

Front 26

Generally, will juvenile or adult trees be easier to propagate from stem cuttings?

Back 26

Juvenile

Front 27

I am annoyed that the sweet gum in my front yard holds its leaves until Thanksgiving, whereas the larger ones I see around campus drop their leaves much earlier. Would you guess that this plant is juvenile or adult?

Back 27

Juvenile

Front 28

Growth rate of annual plants over the duration of a year is sigmoidal (s-shaped) when plotted on a graph (growth rate on y-axis and time on x-axis).

Back 28

True

Front 29

In an annual plant, during both early and late stages of growth there is a relatively equal amount of vegetative and reproductive growth.

Back 29

False

Front 30

Plants generally can skip a specific stage of growth if they are growing vigorously enough.

Back 30

False

Front 31

Exogenous regulation of plant development requires an environmental cue (temperature, light, etc.) in order for the change to take place.

Back 31

True

Front 32

The ultimate fate of cells in the embryo with regard to which tissue layer they will be a part of is already determined by the globular stage.

Back 32

True

Front 33

Endosperm develops solely from maternal tissue independent of double fertilization.

Back 33

False

Front 34

In hyogeous (or hypogeal) germination, as occurs in oaks, the cotyledons stay below ground and typically are not seen.

Back 34

True

Front 35

The central zone of the apical meristem has rapid cell division that leads directly to formation of leaf primordia.

Back 35

False

Front 36

To overcome morphological dormancy of seeds a warm stratification is necessary.

Back 36

True

Front 37

Most of the dry weight of a plant is composed of nitrogen (N), phosphorous (P), and potassium (K).

Back 37

False

Front 38

________ plants grow vegetatively, flower, produce seeds, then senesce and die over a single season.

Back 38

Annual

Front 39

In a seed with deep physiological dormancy and exogenous dormancy caused by a hard seedcoat, one would treat the seeds by __________ in order to promote germination.

Back 39

Scarification then cold stratification

Front 40

The process that produces a zygote from the union of a sperm and egg cell and endosperm from the union of a sperm and two polar nuclei is called ____________.

Back 40

Double fertilization

Front 41

The _________ will become the seed following fertilization.

Back 41

Ovule

Front 42

A seed that has plentiful endosperm, which is uses for energy during germination is referred to as ____________. Common in monocots.

Back 42

Albuminous

Front 43

An alternative form of seed development in which the seed develops asexually is called _____________.

Back 43

Apomixis

Front 44

Cessation of cell division and formation of xylem and phloem vessels takes place first in the ___________ portion of the leaf.

Back 44

Distal

Front 45

__________ promotes maturation of seeds and prevents vivipary.

Back 45

Abscisic acid

Front 46

If a seed is dormant until placed under optimal environmental conditions it is _____________.

Back 46

Quiescent

Front 47

___________ is the simplest method to predict growth and development of plants to coordinate timing of application of cultural practices.

Back 47

Chronology

Front 48

Modifications were made in calculating degree days (heat units) to result in a new unit called growing degree days. Why were these modifications made?

Back 48

Under some conditions, mean daily temperature does not reflect time above the threshold temperature during which plant growth would occur and As temperature increases, the rate of growth and development eventually stops increasing

Front 49

____________ is used to quantify the relationship between temperature and growth and development.

Back 49

Heat summation

Front 50

Monitoring plant growth and development is important because

Back 50

Plants respond differently to cultural practices at different stages of growth and development

Front 51

Mitosis occurs in meristems and serves primarily to provide _________.

Back 51

More cells

Front 52

As an annual plant approaches senescence it ____________.

Back 52

Loses weight in stems and leaves and Begins programmed cell death of all tissues but seeds

Front 53

Chickweed is a winter annual. As a nursery producer, I am trying to determine if I need to spray pre-emergent herbicide to prevent it from germinating during summer. In your opinion, should I spray? Why? Be very brief!

Back 53

I should not spray because there is no germination of a winter annual during summer.

Front 54

How would it be possible to actually get less physiologically effective chilling accumulated (to break deep physiological seed dormancy, for instance) somewhere very cold like Fargo, North Dakota than somewhere more temperate like Asheville, North Carolina? Be very brief!

Back 54

Fargo, North Dakota will have temperatures much lower than are required for physiological processes such as breaking dormancy to occur. Temperatures in Asheville, North Carolina are more temperate and will actually more often be in the range appropriate for accumulating chilling.

Front 55

You are talking to a grower in the southern Georgia sandhills where nutrients and water are not held tightly by the soil. She has put on the perfect amount of fertilizer based on her soil analysis, manages her IPM perfectly, and is otherwise an awesome grower, but her philosophy is to irrigate very little. Explain to her in one short sentence why she will never realize her crops’ full potential managing her farm this way. Hint: Recall the slide with the barrel slats.

Back 55

You cannot have more growth than is allowed by your limiting factor, which in this case is water due to the policy of reduced irrigation.

Front 56

I have propagated a pear tree that is flowering (means it’s adult). After propagating it, the next year it doesn’t flower so I decide to hit it with a high rate of nitrogen and irrigate heavily. Am I going to get this plant to flower quicker? In 10 or fewer words, explain.

Back 56

No, high nitrogen levels, and heavy water both delay flowering.

Front 57

In general, increasing temperatures above some minimum will cause plants to ___________.

Back 57

Flower sooner

Front 58

In obligate vernalization species, a period of chilling is required to _____________

Back 58

Induce flowering

Front 59

Reducing light intensity on sun-adapted species will cause flowering to _____________.

Back 59

Decrease

Front 60

At horticultural maturity, are all fruits physiologically mature? Yes or no.

Back 60

no

Front 61

List 4 physiological or morphological changes that are common in fruits as they mature.

Back 61

Color change

Sugars increase

Respiration Decreases

Firmness Decreases

Front 62

Cell division generally ends ________ in fruit development.

Back 62

Within a week or so after anthesis (short duration)

Front 63

Since cell division is very short in fruit development, what is responsible for the majority of fruit growth?

Back 63

Cell Enlargement

Front 64

Which fruit will have a higher sugar content, fruit collected from a plant cropped to 50 lbs./tree or one cropped to 75 lbs./tree?

Back 64

50lbs./tree

Front 65

The process of increasing or developing freezing resistance is called?

Back 65

Cold Acclimation

Front 66

Are roots of woody plants more or less hardy than stems and buds?

Back 66

Less hardy

Front 67

If a plant has a reported cold hardiness based on lab tests of -45 °C, that means that at no time during the year it will be damaged by temperatures above this.

Back 67

False

Front 68

In order for ice to form, the temperature must be low enough and there must be ________, which serve to orient water molecules.

Back 68

Ice Nucleators

Front 69

Day neutral plants’ flowering and timing is unaffected by photoperiod.

Back 69

True

Front 70

Mericlinal chimeras are the most stable type of chimera.

Back 70

False

Front 71

Ability of stem cuttings to form adventitious roots decreases as plants mature.

Back 71

True

Front 72

Facultative long day plants will flower regardless of photoperiod, but will flower earlier and more profusely under day length greater than their critical photoperiod.

Back 72

True

Front 73

Raising the temperature will always result in more flowers per inflorescence.

Back 73

False

Front 74

Reducing light plants receive generally delays flowering and reduces flower number.

Back 74

True

Front 75

Juvenile plants produce more short shoots than long shoots.

Back 75

False

Front 76

Plants of the same species but of different provenance can be triggered to enter dormancy by different day lengths.

Back 76

True

Front 77

Most juvenile plants do not flower because they do not get enough nitrogen.

Back 77

False

Front 78

Vernalization is chilling to break endodormancy of flower buds.

Back 78

False

Front 79

“Age of plants” can be described in terms of both _________ and ___________.

Back 79

Ontogeny and chronology

Front 80

Skotoperiod is the length of ______________.

Back 80

Uninterrupted dark.

Front 81

Thornless blackberries resulted from a mutation in the L-I histogenic layer. A viable way to propagate a plant that would result in more thornless plants would be:

Back 81

Stem Cuttings

Front 82

If you wanted to collect material from a cherry tree that is reproductively mature, graft it, and have it begin flowering as quickly as possible, where would you collect scion?

Back 82

Upper branches

Front 83

Topophysis is useful in propagation of flowering and fruiting trees, because ____.

Back 83

Physiologically mature materials remain mature and there is a reduced time period to flowering.

Front 84

Phase change in woody plants represents the change from _______________.

Back 84

Vegetative growth to reproductive growth.

Front 85

Generally, when vegetative adult trees are exposed to high rates of nitrogen and low light levels, what effect is produced?

Back 85

Inhibit flowering and increase succulent growth.

Front 86

Apical dominance is an example of this type of dormancy.

Back 86

Paradormancy

Front 87

This type of dormancy can be broken by providing conditions that are favorable for growth.

Back 87

Ecodormancy

Front 88

This is the type of dormancy exhibited by roots of woody plants.

Back 88

This is the type of dormancy exhibited by roots of woody plants.

Front 89

This type of dormancy is removed by accumulation of chilling

Back 89

Endodormancy

Front 90

Photoperiod inducible bud dormancy is driven by the movement of _______ from mature leaves to the terminal bud under short days.

Back 90

ABA

Front 91

Dormancy is triggered by ___________ in dark dominant response plants.

Back 91

A specific duration of uninterrupted dark.

Front 92

The arrangement of leaves around the stem is referred to as ____________.

Back 92

Phyllotaxy

Front 93

Reasons for dormancy in woody plants includes (mark all that apply):

Back 93

Architecture of trees and Survival during unfavorable environmental conditions

Front 94

The ability of cells in the shoot apical meristem to differentiate into any organ in the plant is referred to as _______________.

Back 94

Totipotency

Front 95

Species that set a resting terminal bud in between multiple flushes of vegetative growth during the growing season exhibit ______

Back 95

Recurrent growth

Front 96

In general, increased light levels are associated with:

Back 96

Increased flower production

Front 97

The number of leaves produced during the growing season in fixed growth species is determined ____________.

Back 97

During the previous season

Front 98

Axillary buds that are under apical dominance can be stimulated to grow by:

Back 98

Removing the shoot apex

Front 99

When preparing for dormancy, nutrients within leaves:

Back 99

Translocate to storage organs

Front 100

Many rhododendrons have flower buds present on the plants during autumn; the chilling they will receive during winter will:

Back 100

Break endodormancy

Front 101

Leaf primordia are added to the shoot apex where there are sufficient levels of ____________.

Back 101

Auxin

Front 102

Generally, as temperature rises above some threshold, plants will flower ______.

Back 102

Earlier

Front 103

Red maple is a dark dominant species. If grown in a glasshouse under controlled temperatures, more growth during a year would be achieved if given:

Back 103

Long days

Front 104

Species with buds that have endodormancy can only resume after:

Back 104

They receive sufficient chilling

Front 105

Early leaves are present in the buds of ______________, while late leaves are only found in ____________.

Back 105

All shoots, long shoots

Front 106

Adult material tends to be:

Back 106

Less vigorous

Front 107

Grass in the Willamette Valley tends to stop growing during summer unless it is irrigated. What type of dormancy is this?

Back 107

Ecodormancy

Front 108

All trees exhibit excurrent growth for at least some period of time during their life cycle. Briefly explain why they do this. Is this type of growth specifically due to apical dominance or apical control?

Back 108

Trees exhibit excurrent growth to establish a trunk and to be competitive for sunlight while they are young. This type of growth is due to apical control.

Front 109

Your neighbor planted Emerald Green arborvitae (a conifer that grows over 20 ft. tall and many feet wide) about 1 foot from the sidewalk back in 2005. You see him out with his chainsaw about to severely prune it back to wood that is several years old. Explain to him why the results are may not be attractive.

Back 109

Conifers such as this arborvitae do not have latent buds or the ability to initiate adventitious buds/shoots. So, when this tree is cut back to old wood it will not regrow and there will be an unsightly stump.

Front 110

Hibiscus moscheutos has its stigmas physically separated from its anthers (within the same flower), so even though they are mature at the same time, self-pollination is not guaranteed. However, after 12 hours the stigmas reflex and are self-pollinated. What is the separation of stigmas and anthers called? What is the advantage of this? Why would the plant then foil this separation and self-pollinate by reflexing its stigmas?

Back 110

Herkogamy. The advantage is it encourages outcrossing. The plant would reflex to self-pollinate if not outcrossed within 12 hours to ensure reproductive success; self-pollination is better than no pollination.

Front 111

Your friend brings you some leaves to identify since you are an expert after taking Dr. Contreras’ HORT 226. Based on where your friend collected the leaves, you know the plant is Ulmus parvifolia (chinese elm), which exhibits a good deal of free growth. But the leaves do not have the same morphology and size (exactly) that they did when you learned that species. What is the most likely reason (think shoot growth section*)?

Back 111

The most likely reason is because this species exhibits free growth there are early and late leaves present, which often have different morphology.

Front 112

That same friend that brought you the leaves of chinese elm wants to know another fact so he can impress his new significant other with his horticultural knowledge. Explain to him how you can determine how much a woody plant grew in a single year.

Back 112

You can tell how much growth occurred in a single year by measuring from the terminal bud scar to the tip of the branch.

Front 113

Drought stress leads to leaf senescence, which decreases leaf area to limit the amount of water lost through transpiration.

Back 113

True

Front 114

CO2 is being lost at the temperature compensation point.

Back 114

False

Front 115

Salt injury and drought stress have similar symptoms.

Back 115

True

Front 116

When stomata are closed due to drought stress

Back 116

Photosynthesis and respiration are inhibited, Leaf temperature increases, and Ethylene causes leaves to drop

Front 117

Plants increase levels of ______ in their cells to influence osmotic potential to increase turgor in saline environments.

Back 117

salts (Na+, Cl- and SO42-)

Front 118

In sunlight both red and far red light are present?

Back 118

True

Front 119

Auxin is responsible for cell elongation.

Back 119

True

Front 120

Seeds are NOT capable of sensing light before germination.

Back 120

False

Front 121

Phytochrome…

Back 121

Is in the Pfr state in the presence of redlight and Pr in the presence of far red light