Fruit Crops Test 2

Pick a consideration of site selection and explain why it’s important

Climate: A particular crop is not going to grow well, if at all, in all climates. The climate of the site should reflect the needs of the crop being grown.

Why is irrigation important during establishment? Why is it important during the last 30 days before harvest?

To prevent plant stress; it will affect size, color, and quality of the fruit

Give two critical points of fruit production and explain how heavy rain might affect them

Pollination period: interferes with pollinator activity and decreases fruit set and yield
Harvest period: Difficulty in picking fruit

What is ideal slope range?

2-3%

What is the biggest initial cost? What is one of the biggest ongoing costs? What are other economic considerations?

Land; labor; Unexpected price fluctuations due to world events that seem to happen more often than not

What does proper spacing of plants within rows do?

What does proper spacing between rows do?

What is the importance of row orientation?

Allows plants to reach mature size unimpeded, increases airflow, and makes harvesting easier;

Allows access for equipment;

Increases airflow and sunlight penetration

What are the critical components of establishment phase

Controlling weeds, protecting from sunburn, inspecting for animal damage

What is training? What is pruning?

Positioning limbs, branches, or canes; Cutting limbs, branches, or canes

What are the reasons for training or pruning?

Enhancing fruit quality, improving air circulation, and shaping plant structure

Physiological meaning

of plant processes, growth responses, and overall health management.

What are some physiological responses to pruning

Stimulate lateral branching, reduce or promote vegetative growth

What are some consequences of severe continual pruning

Delay onset of fruiting in young trees

What is plant propagation?

The purposeful act of reproducing plants

Why/how is the TYPE of propagation chosen important in the production of fruit crops?

Affects uniformity, which affects factors like quality, yield, and timing

What is the difference between sexual and asexual propagation?

Sexual propagation involves meiosis and resulting plants are genetically different; asexual propagation only involves mitosis

What is meiosis?

Cell division of germ cells that produces the gametes: sperm or egg

What is mitosis

Cell division of somatic or vegetative cells

What is crossing over (recombination)

Chromatids of one chromosome may exchange genes during early stages of meiosis I

What is independent assortment?

Which allele a gamete receives for a gene has no bearing on the allele a gamete receives for another unlinked gene

Line

A cultivar that reproduces true by seeds

What is asexual propagation

Production of a new plant by any vegetative means only involving mitosis

What is a clone

An organism created through vegetative propagation

What is apomixis

Asexual development of seed or embryo without fertilization

Define air layering

Inducing roots on a stem while it’s still attached to the parent plant

What is mound layering?

shoots are cut back to the ground, then soil or rooting medium is mounded around new shoots as they grow so they grow adventitious roots

Where does meiosis occur? Where does mitosis occur?

Germ cells; somatic or vegetative cells

For two propagation methods:

1. Name: _____

2. Process: ______

3. Advantages: _____

4. Disadvantages: _____

1. Name: _____

2. Definition: ______

3. Process: ______

4. Advantages: _____

5. Disadvantages: _____

1. Seed propagation

2. Required pretreatments vary, but a seed is planted

3. Easier rooting than other propagation methods

4. Variability in new plants is undesirable in production

1. Air layering

2. A type of layer in which an aerial stem is girdle and enclosed with rooting media to produce rooted layers in the upper part of the plant

3. Girdle stem, rooting hormone, moist media, plastic wrap, aluminum foil

4. Reliable for hard-to-root clones

5. Can’t make many air layers per plant because they are so large

Why is air layering so successful?

It is still attached to the parent plant, maintaining a continuous supply of water and mineral nutrients

What is girdling? Why do we do it?

Cutting through or completely removing the bark around the stem. To interrupt downward movement of photosynthates so they will accumulate in the girdled area without interfering with upward water conductance

What are the results of mitosis? What are the results of meiosis?

Two identical daughter cells; 4 haploid gametes

Alternative names for vegetative propagules (little plants that banana sends out)

Suckers, pups

What is grafting?

Union of a rootstock with a scion in such a manner that they grow as one composite plant

What is budding?

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

What is the rootstock?

The lower part of the graft combination that becomes the root system

What is the scion?

The part of the graft combination that becomes the top portion

What is the graft union?

Junction of scion and rootstock

What is top-grafting/working?

Grafting of a new cultivar onto established trees in an orchard

What are the general steps of grafting?

1. Select healthy plants

2. Cut the rootstock

3. Cut the scion

4. Insert the scion

5. Secure the graft

6. Care for the grafted plant

What is necessary for a graft union to be successful?

A vascular connection between the scion and rootstock

What are the three major events in the development of compatible graft?

1. Adhesion of the rootstock and scion

2. Proliferation of callus cells at the graft interface or callus bridge

3. Vascular differentiation across the graft interface

What is the process of the formation of the graft union?

1. Vascular cambium layers of rootstock and scion must be aligned

2. Wound response: Proliferation of callus cells at graft interface, wound periderm forms between necrotic and uninjured tissue

3. Callus bridge formation: Callus tissue forms from undamaged parenchyma, filling in spaces between scion and rootstock

4. Wound-repair xylem and phloem: Wound-repair xylem crosses callus bridge, then WR phloem

5. Secondary xylem and phloem form

Cells of the vascular cambium tissue are _____, meaning they can ________

meristematic; divide and form new cells

Callus forms from

Uninjured parenchyma cells adjacent to cells killed when scion and rootstock were cut

Provide and explain three factors influencing graft union success

Plant species: Some species are less likely to form successful grafts

Environmental conditions: Low temps can decrease or prevent callus tissue formation, high temps can speed up or callus tissue formation or damage tissues

Virus contamination, insects, and diseases

What is bud-forcing? What is one method?

Breaking apical dominance on the rootstock so buds on the scion will start growing; completely removing the rootstock above the scion bud union

Name an advantage and a disadvantage of grafting

Combined strengths of scion and rootstock; risk of incompatibility

What is micropropagation

Propagation of plants from cells, tissues, or organs cultured aseptically

In vivo

Experimentation carried out within intact plants under natural conditions

Explant

Any fragment of plant tissue used as the starting material to grow a plant in tissue culture

In vitro

Experimentation carried out on plants or tissues maintained in clear vessels under artificial and usually sterile conditions

Ex vitro

Transfer of plants from in vitro conditions into soil or potting mixture

2 applications of in vitro culture

Micropropagation of fruit crops, eradication of plant pathogens

List & explain (as needed)the stages of micropropagation

1. Donor plant selection and preparation

2. Establishment of aseptic culture (initiation)

3. Multiplication of propagules

4. Rooting (pre-plant)

5. Acclimatization, transfer to greenhouse and/or natural environment

What happens in stage 1, 2, and 4 of the stages of micropropagation?

1. Donor plant selection and preparation

2. Establishment of aseptic culture (initiation)

3. Multiplication of propagules

4. Rooting (pre-plant)

5. Acclimatization, transfer to greenhouse and/or natural environment

1. choose clean plants

2. Shoot tip, node, or non-meristematic tissues are surface sterilized

4. Produce plants that will survive ex vitro without a supplemental carb supply

List 2 advantages and two disadvantages of micropropagation

Can create genetically identical plants with desired characteristics and produce them year-round; Expensive and requires skilled labor

What is parthenocarpy

Fruit development without fertilization

What is inarching?

Repair graft where rootstock has its own root system, planted in the ground and connected above the wounded area

What is bridge grafting?

Scion is inserted around the injured section and attached upper and lower ends of live, undamaged bark, connecting cambium layers across girdled area

Why do inarching or bridge grafting?

Correct damage done to existing tree

What is disease indexing?

Grafting potentially infected plant tissue onto an indicator plant to test for viral diseases

What is double working?

Grafting a third plant system (interstock) between the rootstock and scion

What does the scion do? How is it chosen?

Determines what the consumers can purchase; market demand and agronomic performance

Rootstocks are ultimately chosen to increase _____ and _____ of the fruit tree. Selection depends on ______ [list 5].

survival; production; location, climate, soil type, pests, diseases

One of the most important management decisions a grower makes is on _________, which is a ______

Cultivar/variety/rootstock selection; dynamic process

What is a potential benefit of selecting a new variety?

Higher economic returns

What are 2 things a grower should do before making a selection?

Study results from local performance tests of different varieties and considering field history of disease and pests

What blend of things will a “good variety” provide?

Desirable horticultural traits, high marketable yield potential, maturity needed to match the cropping season and supply the market, and dependable resistance to diseases, insects, and stress

What is harvested yield?
What is marketable yield?
What is unmarketable/cull yield?

Total quantity of crop harvested;
Portion of harvest suitable for sale;
Portion of harvest that cannot be sold

Total quantity of crop harvested (Name)
Portion of harvest suitable for sale (Name)
Portion of harvest that cannot be sold (Name)

Harvested yield;
Marketable yield;
Unmarketable/cull yield

List three items to consider in selection criteria of a variety

1. Disease and pest resistance

2. Fruit quality and marketability

3. Adaptation to climate

Pest resistant traits protect yield, not enhance yield. Confirm and reaffirm

Confirmed