HORT 201 TAMU Exam 3 - Modules 10-13 - True & False

Soil organic matter improves water retention and nutrient cycling.

True

(Soil organic matter DOES improve water retention and nutrient cycling)

Parent material refers to the organic matter content in the topsoil layer.

False
(Parent material DOES NOT refer to the organic matter content in the topsoil layer)

Soil texture is determined by the proportion of sand, silt, and clay.

True
(Soil texture IS determined by the proportion of sand, silt, and clay)

Soil formation is primarily influenced by five factors: parent material, climate, organisms, topography, and time.

True
(Soil formation IS primarily influenced by five factors: parent material, climate, organisms, topography, and time)

Silt particles are smaller than sand but larger than clay.

True
(Silt particles ARE smaller than sand but larger than clay)

Soils with high cation exchange capacity (CEC) hold fewer nutrients.

False
(Soils with high cation exchange capacity (CEC) DON’T hold fewer nutrients)

Soil bulk density is higher in compacted soils.

True
(Soil bulk density IS higher in compacted soils)

Soil erosion is mainly caused by wind and water movement.

True
(Soil erosion IS mainly caused by wind and water movement)

Silty soils hold more moisture than sandy soils.

True
(Silty soils DOES hold more moisture than sandy soils)

The USDA Soil Taxonomy classifies soils into 12 major orders.

True
(The USDA Soil Taxonomy DOES classify soils into 12 major orders)

Micropores are smaller than 0.000079 inches (0.008 mm) and hold water tightly.

True
(Micropores ARE smaller than 0.000079 inches (0.008 mm) and hold water tightly)

A soil with equal amounts of sand, silt, and clay is classified as sandy loam.

False
(A soil with equal amounts of sand, silt, and clay IS NOT classified as sandy loam)

Alkaline soils (pH > 7.5) may limit the availability of iron and phosphorus.

True
(Alkaline soils (pH > 7.5) DO limit the availability of iron and phosphorus)

Sandy soils are typically well-drained but have low nutrient-holding capacity.

True
(Sandy soils ARE typically well-drained but have low nutrient-holding capacity)

Soil pH affects nutrient availability for plants.

True
(Soil pH DO affect nutrient availability for plants)

Soil horizons develop through processes such as weathering, leaching, and organic matter accumulation.

True
(Soil horizons DO develop through processes such as weathering, leaching, and organic matter accumulation)

Soil structure refers to the arrangement of soil particles into aggregates.

True
(Soil structure DO refer to the arrangement of soil particles into aggregates)

Saline soils are beneficial for most crop plants.

False
(Saline soils ARE NOT beneficial for most crop plants)

Clay soils tend to have better drainage than sandy soils.

False
(Clay soils DON’T tend to have better drainage than sandy soils)

Macropores allow for better air and water movement than micropores.

True
(Macropores DO allow for better air and water movement than micropores)

Climate has little impact on the rate of soil formation.

False
(Climate DOES NOT have little impact on the rate of soil formation)

Soils with high porosity tend to have poor drainage.

False
(Soils with high porosity DO NOT tend to have poor drainage)

Clay soils tend to have a low CEC and poor water retention.

False
(Clay soils DO NOT tend to have a low CEC and poor water retention)

Sand particles are smaller than clay particles.

False
(Sand particles ARE NOT smaller than clay particles)

Soil structure refers to the arrangement of soil particles into aggregates.

True
(Soil structure DO refer to the arrangement of soil particles into aggregates)

Tomatoes require a higher potassium supply compared to nitrogen during fruiting.

True
(Tomatoes DO require a higher potassium supply compared to nitrogen during fruiting)

Calcium (Ca) is crucial for strengthening cell walls.

True
(Calcium (Ca) IS crucial for strengthening cell walls)

Tomatoes, cucumbers, and peppers can all be grown hydroponically.

True
(Tomatoes, cucumbers, and peppers CAN all be grown hydroponically)

A fertilization plan for tomatoes should not be adjusted based on soil test recommendations.

False
(A fertilization plan for tomatoes SHOULD be adjusted based on soil test recommendations)

Cover crops only provide benefits when grown as cash crops.

False
(Cover crops DO NOT only provide benefits when grown as cash crops)

Fertilization should always be applied in a single dose at the beginning of the season.

False
(Fertilization SHOULD NOT always be applied in a single dose at the beginning of the season)

A cover crop such as mustard can reduce soil pathogens.

True
(A cover crop such as mustard CAN reduce soil pathogens)

Leafy greens like lettuce and spinach are well-suited for hydroponic cultivation.

True
(Leafy greens like lettuce and spinach ARE well-suited for hydroponic cultivation)

Clay soils tend to retain moisture but may suffer from poor drainage.

True
(Clay soils DO tend to retain moisture but may suffer from poor drainage)

The three main macronutrients in fertilizers are Nitrogen, Phosphorus, and Potassium.

True
(The three main macronutrients in fertilizers ARE Nitrogen, Phosphorus, and Potassium)

Sandy soils have high nutrient-holding capacity.

False

(Sandy soils DO NOT have high nutrient-holding capacity)

Drip hydroponics delivers nutrients through drip irrigation to plant roots.

True

(Drip hydroponics DOES deliver nutrients through drip irrigation to plant roots)

Sandy soils typically require less frequent fertilizer applications than clay soils.

False

(Sandy soils typically require MORE frequent fertilizer applications than clay soils due to lower nutrient retention)

Fertilization should always be applied in a single dose at the beginning of the season.

False

(Fertilization SHOULD NOT always be applied in a single dose at the beginning of the season)

Crop rotation helps prevent soil depletion and reduces pests and diseases.

True

(Crop rotation DOES help prevent soil depletion and reduce pests and diseases)

Legumes such as clover and vetch fix nitrogen in the soil.

True

(Legumes such as clover and vetch DO fix nitrogen in the soil)

Nitrogen (N) is essential for chlorophyll and amino acid synthesis.

True

(Nitrogen (N) IS essential for chlorophyll and amino acid synthesis)

Crop rotation can reduce the need for excessive fertilizer application

True

(Crop rotation DOES reduce the need for excessive fertilizer application by improving soil health and nutrient cycling)

A common issue with nitrogen deficiency is the yellowing of older leaves

True

(Yellowing of older leaves IS a common symptom of nitrogen deficiency, due to its mobility in the plant)

A soil test is not necessary when planning a fertilization schedule

False

(A soil test IS necessary when planning a fertilization schedule to determine current nutrient levels and pH)

Excessive nitrogen application late in the season can delay fruit maturity.

True

(Excessive nitrogen application late in the season CAN delay fruit maturity by promoting vegetative growth over fruit development)

Hydroponic systems are only suitable for growing leafy greens

False

(Hydroponic systems ARE NOT only suitable for leafy greens; many other fruits and vegetables can be grown hydroponically)

Fertilizer formulations like 10-20-20 indicate the percentage of Nitrogen, Phosphorus, and Potassium, respectively

True

(Fertilizer formulations DO indicate the percentage of Nitrogen (N), Phosphorus (\\text{P}_2\\text{O}_5), and Potassium (\\text{K}_2\\text{O}), respectively)

Loamy soil is generally considered the best for plant growth due to its balanced properties

True

(Loamy soil IS generally considered the best for plant growth due to its balanced properties)

Green manuring involves plowing under cover crops to enrich soil

True

(Green manuring DOES involve plowing under cover crops to enrich soil)

Deep Water Culture systems require plant roots to be submerged in a nutrient solution

True

(Deep Water Culture systems DO require plant roots to be submerged in a nutrient solution)

Potassium (K) plays a key role in enzyme activation and water balance

True

(Potassium (K) DOES play a key role in enzyme activation and water balance)

Hydroponics is a method of growing plants in soil with reduced water input.

False

(Hydroponics IS NOT a method of growing plants in soil with reduced water input)

Manure is an example of an inorganic fertilizer.

False

(Manure IS NOT an example of an inorganic fertilizer)

Vertical farming allows crops to be grown in multiple layers using artificial lighting.

True

(Vertical farming DOES allow crops to be grown in multiple layers using artificial lighting)

Aeroponics is a hydroponic system where plant roots grow in sand.

False
(Aeroponics IS NOT a hydroponic system where plant roots grow in sand; roots are suspended in air and misted with nutrient solution)

Liebig’s Law of the Minimum states that plant growth is determined by the most abundant nutrient.

False
(Liebig’s Law of the Minimum states that plant growth is determined by the LEAST ABUNDANT (limiting) nutrient)

Phosphorus deficiency causes purplish discoloration of leaves and weak root development.

True
(Phosphorus deficiency DOES cause purplish discoloration of leaves and weak root development)

Phosphorus (P) is mainly responsible for regulating water balance in plants.

False
(Phosphorus (P) IS NOT mainly responsible for regulating water balance in plants; Potassium (K) plays this role)

A well-balanced crop rotation includes both nitrogen-fixing plants and heavy-feeding crops

True
(A well-balanced crop rotation DOES include both nitrogen-fixing plants and heavy-feeding crops to maintain soil fertility and health)

Nitrogen is primarily responsible for root development in plants.

False
(N IS NOT mainly responsible for root development; Phosphorus (P) is more crucial for this)

Controlled-release fertilizers provide nutrients gradually over time.

True

(Controlled-release fertilizers DO provide nutrients gradually over time)

Grafting is a technique that involves combining two different plant species to create a new individual plant.

True
(Grafting DOES involve combining two different plant species to create a new individual plant. It combines parts of two plants, often within the same or closely related species, to grow as a single composite plant.)

GMOs take longer to develop compared to classical breeding methods.

False
(GMOs DO NOT take longer to develop; they are often developed more quickly due to targeted gene modification.)

Asexual reproduction in plants requires fertilization

False
(Asexual reproduction in plants DOES NOT require fertilization; it produces offspring from a single parent without gamete fusion.)

Variegated plants are often chimeras

True
(Variegated plants ARE often chimeras, meaning they have different genetic compositions in different tissues.)

Suckering is a form of asexual reproduction where new shoots grow from the root system

True
(Suckering IS a form of asexual reproduction where new shoots grow from the root system.)

Tissue culture allows for the mass production of genetically diverse plants

False
(Tissue culture allows for the mass production of GENETICALLY IDENTICAL plants, not genetically diverse ones.)

GMOs are created by directly modifying plant DNA

True
(GMOs ARE created by directly modifying plant DNA through genetic engineering techniques.)

Classical breeding involves selecting and crossing plants with desirable traits

True
(Classical breeding DOES involve selecting and crossing plants with desirable traits to produce improved varieties.)

Sexual propagation by seed results in genetically identical offspring

False
(Sexual propagation by seed results in GENETICALLY DIVERSE offspring due to genetic recombination.)

Asexual reproduction ensures faster propagation than sexual reproduction

True
(Asexual reproduction OFTEN ENSURES faster propagation than sexual reproduction, as it bypasses the seed stage and often results in larger starting material.)

Plant propagation can be defined as the process of reproducing plants.

True

(Plant propagation IS the process of reproducing plants.)

Asexual reproduction is commonly used in commercial agriculture to maintain desirable traits.

True

(Asexual reproduction IS commonly used in commercial agriculture to maintain desirable traits.)

Grape breeding has led to the development of drought-tolerant varieties.

True

(Grape breeding HAS led to the development of drought-tolerant varieties.)

Tomatoes have been bred to improve disease resistance.

True

(Tomatoes HAVE BEEN bred to improve disease resistance.)

Sexual propagation by seed ensures genetic diversity and adaptability in plants, but also to inconsistent traits.

True

(Sexual propagation by seed DOES ensure genetic diversity and adaptability, but CAN ALSO LEAD to inconsistent traits.)

Tissue culture requires a great deal of attention to sterilization protocols.

True

(Tissue culture DOES require a great deal of attention to sterilization protocols to prevent contamination.)

GMOs are created by directly modifying plant DNA.

True

(GMOs ARE created by directly modifying plant DNA through genetic engineering techniques.)

Cutting is a method of asexual reproduction where a piece of the plant is used to grow a new plant.

True

(Cutting IS a method of asexual reproduction where a piece of the plant is used to grow a new plant.)

Mutation breeding involves using radiation or chemicals to create genetic changes.

True

(Mutation breeding DOES involve using radiation or chemicals to create genetic changes.)

Grafting is a technique that involves combining two different plant species to create a new individual plant.

True

(Grafting DOES  involve combining two different plant species to create a new individual plant. It combines parts of two plants, often within the

A chimera is a plant composed of two or more genetically distinct types of tissue.

True
(A chimera IS a plant composed of two or more genetically distinct types of tissue.)

A major disadvantage of asexual reproduction is the lack of genetic diversity

True
(A major disadvantage of asexual reproduction IS the lack of genetic diversity, leading to susceptibility to widespread diseases or environmental changes.)

Lettuce breeding can focus on improving heat tolerance

True
(Lettuce breeding CAN focus on improving heat tolerance, to adapt to warmer climates and extend growing seasons.)

Asexual reproduction is common in both flowering and non-flowering plants

True
(Asexual reproduction IS common in both flowering and non-flowering plants, e.g., bulbs in flowering plants and fragmentation in some non-flowering plants.)

Nucellar embryony is typical of citrus trees.

True
(Nucellar embryony IS typical of citrus trees, producing genetically identical offspring from maternal tissue.)

Plant breeding enhances resistance to diseases, pests, and environmental stresses.

True
(Plant breeding DOES enhance resistance to diseases, pests, and environmental stresses.)

Grapefruit is an example of hybridization

True
(Grapefruit IS an example of hybridization, resulting from a cross between pomelo and sweet orange.)

Division is a method where a plant is split into smaller sections, each capable of growing independently

True
(Division IS a method where a plant is split into smaller sections, each capable of growing independently.)

In classical breeding, hybridization combines traits from two parent plants

True
(In classical breeding, hybridization DOES combine traits from two parent plants.)

Plant breeding plays a crucial role in developing high-yield, climate-resilient crops.

True
(Plant breeding DOES play a crucial role in developing high-yield, climate-resilient crops.)

Layering is when a stem is bent and covered with soil to encourage root formation.

True

(Layering DOES involve bending a stem and covering it with soil to encourage root formation.)

Plants propagated asexually tend to be more resistant to diseases due to genetic uniformity.

False

(Plants propagated asexually tend to be LESS resistant to diseases due to genetic uniformity, making them susceptible to widespread disease if an infection occurs.)

Grafting is a technique that involves combining two different plant species to create a new individual plant.

True
(Grafting IS a technique that involves combining two different plant species to create a new individual plant.)

The main risk of asexual reproduction is the inability to adapt to environmental changes

True
(The main risk of asexual reproduction IS the inability to adapt to environmental changes due to a lack of genetic diversity.)

Chimeras can only exist in ornamental plants and have no agricultural importance

False
(Chimeras CAN NOT exist in ornamental plants and can have agricultural importance.)

A major advantage of sexual propagation is the cost-effectiveness for large-scale production

True
(A major advantage of sexual propagation IS the cost-effectiveness for large-scale production, especially when using seeds.)

Citrus rootstocks have been bred for disease resistance

True
(Citrus rootstocks HAVE BEEN bred for disease resistance, which is a common practice in horticulture to improve crop health.)

Plants that reproduce asexually can adapt faster to environmental changes than sexually reproducing plants

False

(Asexual reproduction typically leads to a lack of genetic diversity, making plants LESS able to adapt to environmental changes compared to sexually reproducing plants which benefit from genetic recombination.)