Single cross hybrids can be used for a variety of purposes such as-
A. Development of three-way cross hybrid.
B. Development of composite variety.
C. Development of double cross hybrid.
D. Prediction of double cross hybrid.
E. Back cross generation.
Choose the correct answer from the options given below:
A. Development of three-way cross hybrid.
B. Development of composite variety.
C. Development of double cross hybrid.
D. Prediction of double cross hybrid.
E. Back cross generation.
Choose the correct answer from the options given below:
Show Hint
Jenkins Method B Formula: Performance [(A \( \times \) B) \( \times \) (C \( \times \) D)] = $1/4$ (AC + AD + BC + BD).
- A, B, D and E only
- A, B and C only
- A, C and D only
- A, B, C and D only
The Correct Option is C
Solution and Explanation
The question explores the role of single crosses (F\( _1 \) produced by crossing two inbred lines) in hybrid breeding programs and quantitative genetics.
Step 2: Detailed Explanation:
• Three-way Cross (A): A three-way cross is defined as (A \( \times \) B) \( \times \) C. Here, (A \( \times \) B) is a single cross used as the female parent to cross with a third inbred line C.
• Double Cross (C): A double cross is (A \( \times \) B) \( \times \) (C \( \times \) D). This involves the crossing of two different single crosses. This method is often used in maize to reduce seed production costs.
• Prediction of Double Cross (D): According to Jenkins Method B, the performance of a double cross (A \( \times \) B) \( \times \) (C \( \times \) D) can be predicted by taking the average performance of the four non-parental single crosses (AC, AD, BC, BD).
Thus, single crosses are essential for predicting hybrid performance.
• Composite Variety (B): Composites are developed by mixing seeds of several phenotypically outstanding lines and allowing them to open-pollinate. While single crosses could theoretically be part of the mix, they are not a standard primary requirement for "developing" a composite in the way they are for complex hybrids.
• Backcross (E): A backcross is crossing an F\( _1 \) to one of its parents. While a single cross is an F\( _1 \), the term "Back cross generation" is a breeding method rather than a "purpose" or "use" of the single cross in the context of commercial hybrid architecture.
Final Answer:
The most standard and significant uses of single crosses in hybrid technology are for forming 3-way crosses, double crosses, and for performance prediction.
The correct combination is A, C, and D only.
The corresponding option is (C).
Top ICAR AIEEA Plant Sciences Questions
- Both plant and animal cells contain some small organelles called 'peroxisomes', which are dedicated to the metabolism of substances such as
- Chemicals that store energy for the majority of work within cells are called
- The longest phase during the eukaryotic cell cycle is
- The formula: [Sum of (Observed-Expected)$^2$/Expected] is also known as
- Human beings have a large-sized 'proteome'. The principal and more significant reason for this is-
Top ICAR AIEEA Genetics & Plant Breeding Questions
Select the correct statements about origin of the tetraploid and hexaploid wheat:
• [A.] The tetraploid species Triticum turgidum is an allopolyploid.
• [B.] The hexaploid species Triticum aestivum is an allopolyploid.
• [C.] Triticum turgidum arose from a combination of Triticum monococcum and Triticum timopheevii genomes.
• [D.] Triticum aestivum arose from a combination of Triticum turgidum and Aegilops tauschii genomes.The physiological characteristics of wheat plants that adapt different wheat cultivars to different climates include-
• [(A).] Fertilizer requirement.
• [(B).] Vernalization requirement.
• [(C).] Winter hardiness (cold tolerance)
• [(D).] Photoperiod response. Choose the correct answer from the options given below:
Male sterile cytoplasm in crop plants usually arises from-
• [(A).] Inter-specific hybridization
• [(B).] Self-incompatibility
• [(C).] Spontaneous mutation
• [(D).] Induced mutation through Ethium Bromide Choose the correct answer from the options given below:
Which of the following statements is NOT correct?
• [(A).] Seeds of synthetic varieties need to be replaced every year.
• [(B).] Hybrid crops need intensive care and more inputs.
• [(C).] Open pollinated progeny test is used in Maize and Pearl millet.
• [(D).] Composite varieties exploit both GCA and SCA. Choose the correct answer from the options given below:
Which of the following combinations of the premises of 'Gamete Selection' in plant breeding is the correct one?
• [(A).] Multiparent crosses are required for simultaneous improvements of multiple traits.
• [(B).] The male parents of the final crosses are heterozygous and hence heterogametic.
• [(C).] Each zygotic seed is a product of a separate, independent fertilization event.
• [(D).] Gametic selection is an effective method to isolate an inbred for hybrid breeding.
Choose the correct answer from the options given below:
Top ICAR AIEEA Questions
- Which of the following statements is false?
- Which of the following is an example of an inventory?
- According to Adam Smith, productivity gains could be brought about through .
- The supply curve for an artificially scarce good is .
- Which of the following would not be considered an opportunity cost of paid employment?