Given below are two statements:
Statement (I): Reciprocal recurrent selection (RRS) simultaneously improves two different populations in their ability to combine well with each other.
Statement (II): RRS is, however, inferior to the Recurrent Selection for GCA and Recurrent Selection for SCA when dominance is either complete or incomplete.
In light of the above statements, choose the most appropriate answer from the options given below:
Statement (I): Reciprocal recurrent selection (RRS) simultaneously improves two different populations in their ability to combine well with each other.
Statement (II): RRS is, however, inferior to the Recurrent Selection for GCA and Recurrent Selection for SCA when dominance is either complete or incomplete.
In light of the above statements, choose the most appropriate answer from the options given below:
Show Hint
- Both Statement (I) and Statement (II) are correct.
- Both Statement (I) and Statement (II) are incorrect.
- Statement (I) is correct but Statement (II) is incorrect.
- Statement (I) is incorrect but Statement (II) is correct.
The Correct Option is C
Solution and Explanation
Recurrent selection is a cyclic breeding procedure designed to increase the frequency of desirable alleles in a population through repeated selection and intermating of superior individuals.
Reciprocal Recurrent Selection (RRS) is a specialized method that uses two genetically diverse, heterozygous populations as testers for each other to simultaneously improve both populations.
Step 2: Detailed Explanation:
Let us analyze both statements:
1. Analysis of Statement (I): Reciprocal Recurrent Selection (RRS) was proposed by Comstock, Robinson, and Harvey in 1949.
It is designed to simultaneously improve two populations (referred to as Population A and Population B) for their combining ability.
Plants selected from Population A are crossed with a sample of plants from Population B (serving as the tester), and vice versa.
This dual selection improves both General Combining Ability (GCA, mediated by additive gene action) and Specific Combining Ability (SCA, mediated by non-additive gene action, such as dominance and overdominance) between the two populations. Thus, Statement (I) is correct.
2. Analysis of Statement (II): RRS is highly effective because it exploits both additive and non-additive genetic variances simultaneously.
- When dominance is partial or complete, RRS is as effective as recurrent selection for GCA.
- When overdominance is present, RRS is as effective as recurrent selection for SCA.
Therefore, RRS is a versatile, comprehensive breeding method that is superior (not inferior) to GCA-only or SCA-only recurrent selection methods over the long term, as it accommodates all types of gene action. Thus, Statement (II) is incorrect.
Step 3: Final Answer:
Statement (I) is correct, but Statement (II) is incorrect. This corresponds to option (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?