HORT 301 - Test 3

Induced Resistance is an important mechanism of pest control.

 

Which of the following is/are TRUE regarding induced resistance? Select all that are TRUE

1. Salicylic acid is the signaling molecule the plant uses to induce systemic acquired resistance (SAR). Salicylic acid has been commercialized as a SAR-inducing agent. 

2. Commercial products that control plant disease by inducing plant systemic resistance typically have lower toxicity because they kill the pathogen indirectly, by acting on the plant to stimulate disease resistance rather than acting directly on the pathogen. 

3. The active ingredients of some microbial biopesticides are nonpathogenic plant-colonizing bacteria that both kill the plant pathogen directly via the production of antimicrobial compounds and indirectly by inducing plant defenses. The active ingredient of Serenade Bacillus subtilis strain QST 713) is a good example.  

4. Systemic Acquired Resistance (SAR) in plants is typically induced by plant pathogens. Biopesticides containing broad-spectrum virulent plant pathogens have been commercialized and widely adopted as SAR-inducing agents. 

5. Systemic induced resistance results in increased expression of the natural defense mechanisms of plants against various types of pests and pathogens systemically thereby protecting the entire plant, not just the location where the elicitation occurred. 

6. Some bacterial and fungal products such as components of microbial cell walls may cause plants to "sense they are under attack" and respond by inducing resistance systemically.  Several commercial products based on pathogen elicitors of SAR and NOT the pathogens themselves have been commercialized. 

7. Products containing both non-synthetic and synthetic elicitors of induced resistance are labeled as biopesticides because they are thought to be less toxic. 

(5 points)

1, 2, 3, 5, and 6

The first and most important step in having a successful garden is investing in a Good Soil Bed!

 

Which of the following is/are TRUE (good tips for) preparing a good soil bed? Select ALL that are TRUE.

1. The first thing you should do is submit soil samples for soil testing. Checking the box for "Lawns" on the submission form will ensure that you get the proper recommendations for good fruit yields from your vegetable garden. 

2. Add mulch! As we learned mulch can minimize soil loss, minimize weeds, improve water retention, stabilize soil temperatures, improve soil structure and fertility over time, and feed your soil micro- and macro-organisms. 

3. Consider using drip irrigation.

4. Consider adding organic matter, which stabilizes soil structure, increases water retention and availability, increases drainage and aeration, increases nutrient holding capacity, stabilizes pH, supplies plant nutrients (with mineralization), and provides a food source for microorganisms.

5. Till the plot extensively to break up soil clods and mix in any added amendments. As we learned, intensive tilling that removes by mixing most or all of the residue is important for establishing plots that can be Certified Organic.  

(3 points)

2, 3, and 4

Why should you consider using raised beds in your garden?

 

Which of the following is/are TRUE regarding using raised beds in your garden? Select ALL that are TRUE

1. Creates a planting scheme where plants could be easily covered with hoops for frost protection and season extension in fall.

2. Extends the growing season: raised beds allow soil to stay cooler and more water saturated in the spring, providing for earlier spring planting.

3. Reduces soil compaction, improves soil drainage, and provides better soil conditions for crops that need well-drained soils.

4. Provides for a walking or machine path as well as for ease of irrigation.

(3 points)

1, 3, and 4

People garden for many reasons. Some people garden for exercise. 

 

Is it really TRUE that gardening activities like planting, trimming, raking, and weeding for as little as a half-hour can burn more calories than walking an averaged-paced mile?

1. True

2. False

(1 point)

1

Often people find that produce picked and served right from the garden tastes vastly different from produce that has been trucked to the supermarket and stored in the refrigerator before serving. 

 

Which of the following is/are reasons why this might be so? Select all that are TRUE.

1. There is no difference. No studies have demonstrated a difference between produce available in grocery stores and produce direct from the garden in terms of taste or enjoyment.

2. Produce from your garden can be harvested at the optimal degree of ripeness whereas produce harvested for the grocery store may be picked immature, treated with ethylene, stored (during shipping, at the market, in your refrigerator) for more than a week before you eat it. 

3. Many people grow in their gardens varieties that are bred for culinary properties rather than for harvest and post-harvest storage properties. 

(2 points)

2 and 3

Which of the following is/are TRUE regarding the advantages of seeds versus transplants? Select ALL that are TRUE

1. Starting your garden with transplants started with seeds is a form of sexual propagation.

2. A benefit of using seeds is that this shortens the time in the field from germination to maturity and many transplants do not establish as well as seeds in cold wet soils.

3. Tapped-rooted crops such as carrots, radishes, and turnips, legumes like beans and peas, and many cereals like corn make the best transplants. 

4. You have greater choices in which varieties to use when starting from seeds compared to commercially available transplants, where the grower determines which varieties to use for the transplants. 

5. Transplants can improve your establishment success because seeds for transplants can be germinated under controlled environments and the transplants with established root systems will tolerate less than optimal growing conditions compared to freshly germinated seedlings.

6. Transplants give you a head start on your garden because you can start them indoors when the conditions are not appropriate for germination and transplant an established plant (rather than sowing seeds that must germinate and establish) when conditions are favorable. 

7. Starting your garden with sweet potato slips (propagated from stem cuttings) is a form of sexual propagation.

8. Seeds are cheaper as a starting material than transplants.

(5 points)

1, 4, 5, 6, and 8

How deep you should plant a seed depends a lot on the size of the seed. Larger seeds tend to be packed with more nutrients enabling them to emerge from greater depths. 

1. True

2. False

(1 point)

1

It is recommended for home gardens in Texas that crops be either broadcast sown in raised beds, planted in double rows in raised beds, or hill planted. How you should configure the planting area: broadcast, rows, or hills depends a lot on the mature footprint of the plant. Match the crop below with the correct planting configuration.

Crop:

1. Tomatoes

2. Leaf Lettuce

3. Pumpkins

4. Melon

5. Bulb Onions

Planting Configuration:

1. Broadcast

2. Row

3. Hill

1 —> 2, 2 —> 1, 3 —> 3, 4 —> 3, 5 —> 2

When row planting, the spacing you use between plants depends a lot on the mature footprint of the plant, meaning the circumference of the aboveground parts of the plant. If plants are planted too close together, they will compete and shade one another resulting in more plants of poorer quality. If plants are planted too far apart, you may be wasting valuable row space. 

1. True

2. False

(1 point)

1

We talked a lot about Warm Season versus Cool Season Crops. 

Warm season crops are killed by frost and freezing temperatures and require warm soil for good seed germination.

Many Cool season crops will tolerate light frost, and some may even tolerate freezing. Some of these crops terminate when temperatures get warmer.

 

Which of the following is NOT a typical growth form for a cool season plant?

1. Compact flower clusters that go to seed in response to warm temperatures.

2. Produce storage roots and tubers.

3. Open, viny, spreading growth form.

4. Compact growth form (low to the ground).

(1 point)

3

For each crop below indicate whether it is considered a Warm or Cool season crop in Texas. 

1. Beans

2. Melons

3. Tomato

4. Carrots

5. Kale

6. Brocolli

1 —> warm, 2 —> warm, 3 —> warm, 4 —> cool, 5 —> cool, 6 —> cool

When you START your garden in the spring—what should you be concerned with?

1. Pay attention to when the soil temperature is warm enough for good seed germination.

2. Pay attention to the average fall first frost date. If planting a late summer/early fall warm season crop, frost will terminate flowering and cause plant death

3. Pay attention to the average date of the last winter frost in the spring because frost will kill young plants without protection. 

4. Pay attention to warming spring temperatures because this will cause some warm season crops to bolt, i.e., switch from vegetative growth to flowering in spring.

5. Pay attention to the average fall first frost date because warm season crops require cooler temperatures for growth, but young plants should be protected from frost.

6. Pay attention to the time to harvest. Need to get the crop planted and harvested before hot summer temperatures set in.

(4 points)

1, 2, 3, and 6

Extending the growing season can help growers create new markets and greater profit because they can harvest produce earlier or later in the season when locally grown produce may be less available.

 

Which of the following would help growers extend their growing season?

1. Growing crops under row covers or high tunnels will trap heat in the spring to warm the soil or prevent frost in the fall providing for a longer season.

2. Caging individual plants in lightweight material can keep plants warmer and protect them from frost at both ends of the growing season as well as protect them from sunscald during the summer months. 

3. Plastic mulch like row covers will extend the planting and growing season but plastic mulch will also slow moisture loss and minimize weeds.

4. Starting transplants indoors can give you a head start on your garden in spring. 

5. All of the choices.

(1 point)

5

Tomatoes were introduced first in this course because so many people grow them, but also because there is a lot of terminology that goes with tomato production. 

 

Match the definitions below with the correct terms. 

1. A variety suitable for commercial field production because fruits ripen at one time

2. A variety that would give you tomatoes continuously over a long season.

3. A tomato label indicating the variety has high disease resistance to a variety of pathogens

4. An old variety not typically used in large scale production and thus has traits not typically encountered in supermarket tomatoes. It is typically open pollinated, true to type.

5. A variety created by crossing two parental varieties with very distinct traits, resulting in an offspring with new more desirable traits due to the blending of traits from both parents.

6. A physiological disorder in tomato caused by calcium deficiency.

7. Tomato varieties that are considered true-to-type because they have kept traits through time via outcrossing.

1. VFTN

2. Blossom end rot

3. Determinate flowering

4. Indeterminate flowering

5. Heirloom

6. Hybrid

7. Open pollinated

1 —> 3, 2 —> 4, 3 —> 1, 4 —> 5, 5 —> 6, 6 —> 2, 7 —> 7

Tomato Hybrids typically have more desirable traits than either of the parents that was used to generate them. Thus, it is a good idea to save the seeds of hybrids if you want all the seeds for the next generation to also have the same desirable phenotype as the hybrid. 

1. True

2. False

2

Although most people grow tomatoes as annuals, tomatoes are actually perennial plants that can persist for multiple growing seasons.

1. True

2. False

1

Which of the following is FALSE regarding crops in the Brassicaceae

1. Brassica crops typically have yellow flowers with four petals that are arranged in a cross pattern. For these reasons, Brassica crops are also referred to as mustard crops or Cruciferae. 

2. Brassica crops include a few but not all crops referred to as leafy greens such as mustard greens, turnip greens, kale, and collard greens.

3. Many of them are cool season crops that are terminated by bolting. 

4. Brassica crops include broccoli, cabbage, cauliflower, and Brussel sprouts.

5. Brassica crops include several root crops including radishes, turnips, and carrots.

(1 point)

5

It is quite surprising that Texas A&M was able to breed a maroon carrot since all carrot varieties are orange. 

1. True

2. False

2

Onions are typically started from seeds or onion sets, which are small onion bulbs that have been grown from seed in the previous season and forced into dormancy at an immature stage. Both of these are sexual methods of plant propagation. 

1. True

2. False

(1 point)

1

Which of the following is FALSE regarding growing Irish potatoes in Texas?

1. Although potatoes flower and produce seeds (which are valuable to breeders who are producing new varieties by crossing different parents), potatoes are propagated from pieces of tubers, which both produce a crop that is identical to the parental crop and give that crop a head start over plants produced from seed. 

2. Because Texas has relatively few insect-vectored virus problems, saving last year's seed pieces to start this year's crop is highly recommended. 

3. Irish potato varieties bred and grown in Texas may differ in the color and texture of the skin, the color of the flesh, and even the shape of the tuber.  

4. Commercially grown potatoes are typically vine-killed about two weeks before harvest to facilitate mechanical pick-up.

(1 point)

2

Different types of beans and peas are harvested when the pods and seeds reach different degrees of ripeness. 

 

Match the type of bean or pea to the degree of ripeness at harvest. 

1. Green Beans

2. Pinto Beans

3. Butter or Lima Beans

4. Field Peas

1. Pods green, seeds developing

2. Pods mature, seeds moist

3. Pods mature, seeds dry

(4 points)

1 —> 1, 2 —> 3, 3 —> 2, 4 —> 2

TRUE or FALSE: Many members of the Fabaceae (Legumes) are referred to as nitrogen fixers because the roots of these plants form symbiotic associations with certain bacteria (rhizobia) that actually fix nitrogen and share it with the plant.

1. True

2. False

(1 point)

1

Peppers can be a hot topic. 

 

Which of the following is FALSE regarding peppers?

1. Because tomatoes and peppers are both plant fruits, giving tomato or pepper plants excessive nitrogen will decrease and delay blooming due to lavish vegetative growth. 

2. Similar to onions, the heat of peppers is measured in Scoville units which is based on the amount of allicin the pepper produces. 

3. Scoville Units were originally determined by a panel of taste testers, but now pungency is measured via chemical methods such as HPLC. 

4. Solanaceous crops including tomatoes, peppers, and eggplants are typically propagated sexually from seeds or transplants started from seeds, whereas Irish potatoes, another Solanaceous crop are typically propagated asexually from seed pieces.

(1 point)

2

Okra is in the same family as another important Texas crop. So, if you wanted to minimize green bridges for insects and pathogens you might NOT locate your okra crop next to a field of this crop. 

The name of the important Texas crop that okra is related to: ______

Cotton

Corn is an example of a monoecious crop.

 

Which of the following is FALSE regarding maize?

1. An "ear" of corn is an inflorescence of perfect flowers. The corn kernels develop from the ovary whereas the pollen is contained in anthers on the ends of the "silks" (filaments). 

2. The ear is a pistillate inflorescence, i.e., comprised of female flowers with stigma, style and ovary.

3. Corn tassels are inflorescences of male flowers with stamen. 

(1 point)

1

Which of the following is FALSE regarding sweet potatoes?

1. Certain varieties of sweet potato plants are used as ornamentals. 

2. Although sweet potatoes are commonly referred to as yams, they are not yams. 

3. Sweet potatoes, like Irish potatoes are tubers, i.e., underground storage stems. 

4. Sweet potato plants are propagated asexually from slips, which are rooted stem cuttings typically obtained from mature sweet potatoes. 

(1 point)

3

The Cucurbitaceae are subtropical in origin. We typically eat the "fruits". Cucumbers come in monoecious (standard), gynoecious, and parthenocarpic varieties! Wow! 

Match the description to the type of cucumber variety. 

1. Varieties that produce both male and female flowers and the male flowers are produced first, with female flowers following later in development.

2. Varieties that produce only female flowers and fruit develops without pollination.

3. Cucumber varieties that produce only female flowers but must be pollinated (bees) for fruit development.

1. Standard, monoecious

2. Gynoecious

3. Parthenocarpic

(3 points)

1 —> 1, 2 —> 3, 3 —> 2

Seedless cucumbers are parthenocarpic varieties of cucumbers that are seedless, or nearly so because the fruit develops in the absence of fertilized seed. Parthenocarpic varieties occur naturally and will develop seeds if pollinated.

In contrast to cucumbers, there are no pathenocarpnic varieties of watermelons and seedless watermelons are generated from triploid plants.  n is 1n), the resulting seed produces a triploid (3n) daughter plant. Production of the triploid seed (that will produce seedless watermelons) requires special breeding measures that ensure a tetraploid parent is pollinated only by pollen from a standard parent.

 

Which of the following would be a good practice to obtain triploid seed? (You got this!)

 

1. Plant the pollen and seed parents in alternating rows and remove (discard) all staminate flowers from the pollen parent rows during flowering. 

2. Plant the pollen and seed plants in alternating rows and do not remove any flowers. 

3. Plant the pollen and seed parents in alternating rows and remove (discard) all staminate flowers from the seed parent rows during flowering time.

4. Plant the pollen and seed plants in alternating rows and remove (discard) all flowers from the pollen parent.

(1 point)

3

The benefits of companion plantings include all of the following EXCEPT

1. Attracting beneficial insects to the garden.

2. Providing ground cover to protect against weeds. 

3. Serving as green bridges that attract plant pathogens and insects. 

4. Serving as a form of preventative or cultural control in an IPM strategy by acting as trap plants or deterrents of insect pests. 

(1 point)

3

The planting configuration you use depends on the mature footprint of the individual plants.

Match the crop with the correct planting configuration. 

1. Many cucurbits including squash, pumpkins, and melons

2. Onions like Texas's 1015 sweet variety

3. Brassica crops like broccoli, cauliflower, and cabbage

4. Many Solanaceous crops like tomato, potato, and peppers

5. Leafy Brassica crops like kale and collard greens

1. Hill

2. Broadcast sown on raised beds

3. Double row on raised beds

(5 points)

1 —> 1, 2 —> 3, 3 —> 3, 4 —> 3, 5 —> 2

Comparing "vegetable crops" production to "fruit crop" production, which of the following statements ARE TRUE?

1. Whereas many "vegetable crops" are propagated asexually via seed and grown as annuals, many fruit varieties are propagated vegetatively (sexually) and must be grown as perennials.  

2. Although some high-value "vegetable crops" are grafted, because it may take years for a fruit tree to reach production age, many fruit trees are grafted via the union of a scion with high fruit quality to a rootstock with good pathogen resistance.

3. Strawberries have been bred to have small seeds. If you wanted to propagate strawberries from seed you could, but you might need to use a larger-seeded variety or germinate the small seeds indoors to aid the plants in establishing and then plant the transplants outdoors. 

4. Grafting fruit crops by combining size-controlling rootstocks with a scion with good fruit quality can be done to manage plant height. 

5. To maintain the integrity of the fruit quality, many fruit crops are propagated vegetatively because the progeny are then clones of the high quality parent. 

(4 points)

2, 3, 4, and 5

Which of the following are TRUE regarding "Rosaceous berry" crops? Select ALL that are TRUE.

1. For strawberries, blackberries, raspberries and dewberries, efficient bee pollination is required to fertilize every ovary; without effective pollination some ovaries will not be fertilized and the fruit will be misshaped.  

2. Strawberries, blackberries, raspberries and dewberries are all non-native to Texas but all are grown commercially throughout Texas.

3. Strawberries, blackberries, raspberries and dewberries are all fruit crops in the Rosaceae family.

4. Strawberries are typically grown as an annual crop whereas blackberries and raspberries are grown as a perennial crop. 

5. Strawberry runners for field planting are often propagated via tissue culture.

6. There are varieties of strawberries that grow well and produce fruit in containers. Good bee traffic is required for good fruit development. 

7. Strawberries are most typically propagated from runners whereas blackberries and raspberries are typically propagated from seeds.

8. Strawberries, blackberries, raspberries and dewberries all produce upright canes that must be trellised. 

9. Blackberries typically have biennial canes and perennial crowns and root systems.

10. Strawberries, blackberries, raspberries and dewberries are not actually berries. The fruits are actually aggregate fruits produced by single flowers with multiple ovaries.

11. Strawberries are typically planted in raised beds that are either covered by straw or plastic. The raised beds facilitate drainage and fertility management. Covering the raised beds with straw or plastic helps protect the fruits that would otherwise come in contact with the soil from soil borne pathogens and insects.  

(8 points)

1, 3, 4, 5, 6, 9, 10, and 11

Pruning to "force nutrients" into new growth for fruit production is an important management principle. Which of the following strawberry or blackberry management practices is an example of this "forcing" concept? Select ALL that are TRUE.

1. Pruning by topping blackberry primocanes that will produce next year's floricanes and fruits to about head height.  

2. Removing all the blackberry floricanes that produced fruit the previous year to create space for new primocane growth that will produce the buds for the next year's floricanes.

3. Allowing strawberry runners to spread freely and root at will within the row to form a crisscrossed, matted row about 24 inches wide.

4. Based on the forcing concept, if you wanted to grow the largest strawberries, you would use the Matted Row system.

5. "Hill System" planting strawberries in a staggered pattern and removing runners as they are produced. 

6. Selecting and keeping three to four strong and healthy blackberry primocanes from each blackberry plant and pruning out the rest of the primocanes.

(4 points)

1, 2, 5, and 6

Which of the following is/are TRUE regarding grapes and grape production? Select ALL that are entirely TRUE. Hint pay attention to scion and rootstock in each selection.

1. Muscadine grapes are large, round, and thick-skinned grapes native to the southeastern United States. Becuase of their tough skin and challenges eating them they are not commonly found in supermarkets.

2. A great choice for first-time growers in Texas who want grapes or an arbor to provide shade is Champanel,  an American hybrid developed by Thomas Volney Munson, which provides both natural disease resistance and adaptation to local conditions and Concord fruit qualities. 

3. The best place to locate your grape vineyard is in the shade of your production buildings to keep the grapes out of the sun and protect them from sunscald and keep the leaves as moist as possible to protect them from desiccation. Maintaining excess vegetative growth can also help fruit production.

4. Concord grapes are a sweet grape that can be used as table grapes or sweet wine grapes, but are primarily used to make grape jelly, grape juice, grape-flavored soft drinks, and candy.

5. Botanically, grapes are berries.

6. Grape rootstocks used to produce French American hybrids are typically produced sexually by planting seeds collected from French-American hybrids. 

7. Grapes are mostly grafted, joining a high-quality wine scion to a pest and stress-tolerant rootstock. Because some Texas varieties used for rootstock production such as 'Black Spanish' have been found to produce quality wine when grown on their own rootstocks the use of non-grafted varieties is becoming more common in Texas.  

8. Vinifera varieties are the common European grape varieties that are the chief source of Old World wine and table grapes.

9. Pruning is essential for maintaining vine health and maximum production of quality fruit.

10. Like many other perennial crops, grapevine bud and flower formation is a two-year process.  Buds initiated during shoot growth in the first season produce shoots with flowers for the following growing season. 

11. Many North American grape varieties are naturally resistant to or have high tolerance of certain devastating insect pests such as grape phylloxera and Pierces Disease and thus are frequently used as the scions with French rootstocks to create French-American Hybrids.

12. Thomas Volney Munson is often credited for saving the French wine industry because he provided the French industry with cuttings from Texas grape varieties that were then used as scions for the production of wines resistant to the fungal disease known as grape phylloxera.

(8 points)

1, 2, 4, 5, 7, 8, 9, and 10

Match the description with the pruning technique. (Make sure you could also match a photo of a pruned vine with the pruning technique). 

1. A pruning system that utilizes a woody scaffold where this season's primocanes are cut back to spurs with only a few buds on them.

2. A pruning system that utilizes this season's primocane as the scaffold and buds are removed from these canes except for a few well-spaced buds.

1. Cordon pruning

2. Cane pruning

1 —> 1, 2 —> 2

Which of the following is/are TRUE regarding propagation rootstocks via hardwood cuttings? Select ALL that are TRUE.

1. The top cut is made at a 45-degree angle to remind the producer to put the cutting into the pot, pointy edge facing downward. 

2. Typically, all but two buds are removed to force energy into the remaining buds to facilitate the production of two vigorous new shoots next year. 

3. The material used for the cuttings is typically a 1-yr old cane. 

4. Root production is based on the principles of layering: a cut is made through the bottom bud wounding it and then the cut stem is placed in a container of moistened potting mix, which encourages root production at the stem node. 

(3 points)

2, 3, and 4

Which of the following is/are TRUE regarding fig production? Select ALL that are entirely TRUE.

1. Fig varieties may be monoecious, dioecious, or parthenocarpic and are typically propagated via cuttings to ensure that new trees are female and “true to type”, although layering is also used. 

2. Although figs can be grown throughout Texas and were among the most common fruits grown by homesteaders, figs will die back with severe freeze. Growing figs as multi-stem shrubs rather than trees will help them come back more readily from freeze events. 

3. The varieties commercially grown in Texas are parthenocarpic. They typically have an open eye for pollinators and fruits are formed without souring.

4. There are naturally parthenocarpic fig varieties that produce fruits without being pollinated. These are typcially sexually propagated. 

(2 points)

1 and 2

Which of the following is/are true regarding citrus? Select all that are TRUE.    (For the exam make sure you can name at least 6 different types of citrus!)

1. Oranges, grapefruits, lemons, limes, tangerines, satsuma mandarins, kumquat, citron, and pomelo are all types of citrus fruits

2. Most oranges in Texas are grafted onto either sour orange or trifoliate orange rootstock, both of which are better adapted to Texas soil and environmental conditions.

3. Citrus crops are subtropical in origin. This means that they tend not to be deciduous (are green in winter) and are extremely frost sensitive. 

4. After a freeze, grafted citrus must be inspected to ensure that the new growth arises below the graft union. In areas with frequent frosts, it is desirable to encourage growth and fruit production from the more frost-tolerant sour orange rootstock. 

5. Always plant grafted citrus such that the graft union is below the soil surface. 

6. Never start your citrus seedlings from saved supermarket citrus seeds. Citrus are sold as grafted, pruned seedlings. Grafting mature scions to stress-tolerant rootstocks shortens the time to fruit production, ensures that new trees are "true-to type", and provides a level of stress tolerance not found in the commercial fruit variety.

7. Many types of citrus are adaptable to container production. Historically, large greenhouses used to grow container oranges and other fruit trees during the winter in northern Europe and North America were referred to as orangeries.

8. Citrus fruits are actually a type of berry with a leathery outer layer known as a hesperidium.  

(6 points)

1, 2, 3, 6, 7, and 8

Which of the following is/are TRUE regarding sexual and asexual plant propagation. Select ALL that are TRUE.

1. Whether you are producing annual "vegetable crops" or perennial fruit crops, grafting is considered a form of sexual reproduction because the rootstock and scion are always started from seed. 

2. Sexual reproduction involves the union of the pollen and egg, drawing from the genes of two parents to create a new individual. Sexual propagation involves the floral parts of a plant.

3. Many garden "vegetable crops" (i.e. crops typically grown as annuals whether we eat the fruits or vegetative parts) are propagated via sexual reproduction including important Brassicaceae, Cucurbitaceae, and Fabaceae crops.

4. Asexual reproduction includes the propagation of a new plant from a fragment of the parent plant (typically vegetative parts of a plant such as stems, roots, or leaves) or a specialized reproductive structure (such as a stolon, rhizome, or tuber). The resulting new plant is genetically identical to the parental material from which is derived.

5. Although seedless cucumbers are produced parthenocarpically (i.e., without fertilization), seedless varieties are still propagated sexually via seeds produced when parthenocarpic varieties are crossed with standard varieties.

6. Irish potatoes and sweet potatoes are both root crops that are propagated asexually from slips, which are rooted stem cuttings.

7. Although perennial fruit crops are typically propagated asexually, starting tree fruit crops from seed is the preferred method for large orchards because it is by far the cheapest way to produce fruit quickly.

8. Perennial fruit crops are typically propagated asexually for several reasons including: to maintain the integrity of perennial fruit varieties, because preferred varieties often have been bred to be have few seeds, and because seeds may have lengthy and complex dormancies and require a longer time to maturity (fruit production) than asexually propagated plants.

   
   

(5 points)

2, 3, 4, 5, and 8

Which of the following is/are TRUE regarding cuttings and layering for plant propagation? Select ALL that are TRUE.

1. Air layering is a process that is often used to propagate figs and other woody plants. Plants are typically wounded by removing the bark to expose the vascular cambium. Then the wound is layered with moist potting mix which encourages adventitious root developed. It is called air layering because the roots develop in the air, on the aerial part of the plant.

2. Cuttings are a method of propagation where the new plant remains at least partially attached to the mother plant while forming new roots or stems whereas Layering is are method of propagation where the new plant is completely separated from the mother plant while forming new roots and stems.

3. Micropropagation is a method of asexual plant propagation that uses small cuttings of plant tissue taken from a carefully chosen mother plant and grows these under laboratory conditions to produce new plantlets that can then be transferred to the field. It is widely used in commercial horticulture.

4. Cuttings from mature trees are often used as scion wood in grafted trees to shorten the time to fruit production.

5. Leafy cuttings typically require well-drained medium, but little moisture control whereas hardwood stem cuttings typically require high humidity to prevent excessive dehydration. Thus hardwood stem cuttings are typically propagated in greenhouses with intermittent mist or fog systems.

6. Hardwood cuttings are often used to propagate grape or citrus rootstocks. For grape rootstocks it is advisable to cut a short section of the cane with 5-6 buts on it. The bottom of the cane is typically cut flat through the bottom bud and the top of the cane is pruned to a point. All of the remaining buds are left on the cane and encouraged to produce new shoots because more shoots is always better than a few.

7. Mound layering or stooling is often used to propagate apple rootstocks. This is accomplished by mounding soil to cover the base of adventitiously produced shoots that form from the crown of a "mother" rootstock tree that has been topped. Mounding encourages adventitious root formation at the base of the shoots and then these daughter plants can be used as rootstock for grafted plants.

8. Both leafy cuttings and hardwood stem cuttings must be started in potting medium that is disease-free, well-drained, and lightweight. Gibberellic acid application is now standard to encourage root growth.

9. Tip layering and Simple layering are both examples of asexual reproduction where new daughter plants develop from buds on buried stems. Although both methods are commonly used to propagate certain fruit crops such as blackberries and grapes this process also occurs naturally for some fruit crops.

(5 points)

1, 3, 4, 7, and 9

Which of the following is/are TRUE regarding scion and bud grafting? Select ALL that are TRUE.

1. Bud Grafting is a practice of grafting can be traced back ~4,000 years and is common practice especially for top working.

2. Scion wood is typically selected for disease or stress tolerance characteristics whereas rootstock wood is typically selected for preferred fruit characteristics. 

3. T-budding is a popular method for fruit tree propagation except for walnut, pecan, and grape. Chip budding is often used for grape. Walnut and pecan do not bud graft well. 

4. As compared to cleft grafting, bark grafting is rapid, simple readily performed by amateurs, and if properly done, gives a high percentage of “takes”.  It requires no special equipment.

5. Scion grafting, uses a short section of a shoot of the desired cultivar (scion) whereas bud grafting, uses a single detached bud of the desired cultivar.

6. Because many types of citrus species are graft compatible it would be possible to purchase a citrus "fruit salad tree" having lemon, orange, mandarin, and lime scions grafted to the same rootstock. 

7. In Texas, grafting is often performed in the spring but this requires some planning because the budwood must be collected just prior to bud break and then kept in moist cold storage (35° F) until the rootstocks are slipping and actively growing. Then the budwood is moved to a warm area for a few days until it too is slipping.

8. When grafting we want the scion or bud wood we are grafting to be actively growing at the time we are grafting so that a new connection can be rapidly formed.  Pushing out new leaves and shoots immediately after grafting helps the graft union heal faster. 

9. Bud grafting is often a preferred technique it requires less material than scion grafting but some trees do not bud graft well and bud grafting is not suitable for all situations. 

10. When grafting we want the bark of the rootstock to be to be able to slip at the time we are grafting so that the vascular cambium can be exposed. This typically happens when the rootstock is awake (not dormant).

11. Topworking is useful for changing out the scion variety on a mature tree. This a common practice in commercial fruit production where a variety may fall out of favor and different variety becomes more profitable. Cleft grafting is the most common method of topworking. 

12. Grafting is a common practice for fruit crops. In apples grafting can be used to improve hardiness, for size control, or to alleviate fertility compatibility issues. For example, compatible apple varieties can be grafted together to create a tree that can self-pollinate and ensure good fruit production.

13. Given the dormancy/activity requirements of the scion and rootstock, sometime around Thanksgiving is be a good time to graft fruit trees in most of Texas because the buds on the scion wood are mature but not actively growing and the rootstock wood is still active enough to slip. 

(10 points)

3, 4, 5, 6, 7, 9, 10, 11, 12, and 13

Grafting is most typically performed on which of the following? (Make sure you know why)

1. Both monocots and dicots

2. Monocots

3. Dicots

(1 point)

3