1. Which of the following is the primary goal of fiber crop breeding?
a) Increasing the seed yield
b) Enhancing fiber length and quality
c) Improving the plant’s resistance to diseases
d) Reducing the time to harvest
Answer: b) Enhancing fiber length and quality
Explanation: The primary goal in fiber crop breeding is to enhance the quality of the fiber, which includes improving its length, strength, fineness, and uniformity, as these are critical traits for commercial fiber production.
2. In cotton breeding, which of the following is a key trait being selected for improving fiber quality?
a) Seed coat color
b) Fiber fineness (micronaire value)
c) Root depth
d) Chlorophyll content
Answer: b) Fiber fineness (micronaire value)
Explanation: Fiber fineness (micronaire value) is an important trait in cotton breeding because it directly affects the strength and quality of the fiber, influencing its use in textile manufacturing.
3. Which of the following is a commonly used technique in the breeding of fiber crops to improve disease resistance?
a) Mutagenesis
b) Hybrid vigor
c) Marker-assisted selection
d) Grafting
Answer: c) Marker-assisted selection
Explanation: Marker-assisted selection (MAS) is a modern breeding technique that uses molecular markers to identify desirable traits such as disease resistance, thereby improving the precision and efficiency of breeding fiber crops.
4. What is the role of “genomic selection” in breeding fiber crops?
a) To improve fiber length and quality through conventional breeding
b) To select desirable traits based on the genomic data of the plant
c) To increase the amount of fiber produced per hectare
d) To enhance the aesthetic qualities of the plant
Answer: b) To select desirable traits based on the genomic data of the plant
Explanation: Genomic selection uses genomic data to predict the performance of untested individuals, enabling breeders to select for desired traits more efficiently, such as fiber yield, quality, and disease resistance.
5. Which fiber crop is primarily known for its use in producing jute, an important natural fiber?
a) Cotton
b) Flax
c) Jute
d) Hemp
Answer: c) Jute
Explanation: Jute is a fiber crop that is primarily grown for its fiber, which is used in producing a wide range of products such as bags, ropes, and mats. It is often referred to as the “golden fiber.”
6. In the breeding of flax for fiber production, what is the ideal plant height that breeders aim for?
a) Shorter plants for better disease resistance
b) Moderate plant height for optimal fiber yield
c) Taller plants for stronger fibers
d) Very tall plants for high seed yield
Answer: b) Moderate plant height for optimal fiber yield
Explanation: In flax breeding, moderate plant height is desirable as it results in optimal fiber yield, which is long and fine. Excessive height may lead to lodging, which can decrease the quality of fiber.
7. Which of the following is a critical factor affecting the fiber strength of cotton?
a) Seed size
b) Fiber maturity
c) Leaf color
d) Soil pH
Answer: b) Fiber maturity
Explanation: Fiber strength is largely determined by the maturity of the cotton fiber. Fully matured fibers are stronger and more resilient, while immature fibers can be weak and brittle.
8. Which of the following is the primary genetic source for disease resistance in cotton breeding?
a) Wild cotton species
b) Commercial cotton varieties
c) Transgenic cotton varieties
d) Non-cotton fiber crops
Answer: a) Wild cotton species
Explanation: Wild cotton species are a rich genetic source of resistance to various diseases, including Fusarium wilt and Verticillium wilt. These wild relatives are often used in breeding programs to introduce disease resistance into cultivated cotton varieties.
9. In the breeding of fiber crops like hemp, which of the following traits is prioritized for industrial uses?
a) Seed size
b) Fiber length and strength
c) Flowering time
d) Pest resistance
Answer: b) Fiber length and strength
Explanation: For industrial applications, such as the production of textiles, paper, and biocomposites, fiber crops like hemp are bred for long, strong fibers that are suitable for processing and manufacturing.
10. What is the main challenge in breeding fiber crops for climate change adaptation?
a) Increasing fiber yield
b) Enhancing fiber quality
c) Developing drought and heat-tolerant varieties
d) Reducing pest susceptibility
Answer: c) Developing drought and heat-tolerant varieties
Explanation: As climate change leads to more extreme weather conditions, breeding fiber crops that can tolerate drought, heat, and other abiotic stresses is a major focus to ensure stable fiber production.
11. Which of the following techniques is used to create genetically modified fiber crops with improved traits like pest resistance or herbicide tolerance?
a) Crossbreeding
b) Gene editing
c) Conventional mutation breeding
d) Somaclonal variation
Answer: b) Gene editing
Explanation: Gene editing techniques, such as CRISPR-Cas9, are used to create genetically modified fiber crops by precisely editing the DNA to introduce desired traits, such as pest resistance or tolerance to herbicides.
12. Which of the following is a commonly used breeding method for improving fiber yield in cotton?
a) Mutation breeding
b) Hybrid breeding
c) Grafting
d) Tissue culture
Answer: b) Hybrid breeding
Explanation: Hybrid breeding is often used to improve fiber yield in cotton by combining the desirable traits of two different parental lines, thereby increasing yield and improving fiber quality through hybrid vigor.
13. In flax breeding, what is the most important characteristic affecting fiber quality?
a) Number of seeds per plant
b) Plant maturity at harvest
c) Presence of lignin in the fiber
d) Root depth
Answer: b) Plant maturity at harvest
Explanation: The timing of harvest is critical in flax breeding to ensure the fiber reaches its optimal quality. Early or late harvesting can negatively affect the fiber quality, including its strength and fineness.
14. What is the primary advantage of using polyploidy in the breeding of fiber crops?
a) Increased fiber length
b) Enhanced disease resistance
c) Increased fiber yield through larger cells
d) Improved seed germination rate
Answer: c) Increased fiber yield through larger cells
Explanation: Polyploidy involves the duplication of an organism’s chromosomes, which can lead to larger cell sizes in fiber-producing plants. This increase in cell size can result in higher fiber yield.
15. Which of the following techniques is used to assess the genetic diversity of fiber crops in breeding programs?
a) Gel electrophoresis
b) Genetic fingerprinting
c) Clonal selection
d) Pollen viability tests
Answer: b) Genetic fingerprinting
Explanation: Genetic fingerprinting is used to assess the genetic diversity of fiber crops, helping breeders identify distinct genotypes and select parents with desirable traits for further breeding.