Question
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Horizontal resistance is durable as it is non-race specific.
Reason R: Race specific resistance puts pressure on the pathogen to evolve more virulent races.
In the light of the above statements, choose the most appropriate answer from the options given below
This question was previously asked in
CUET PG 2026 Agri-Business Management Question Paper (25-Mar-2026) (Shift 2)
The correct answer is
Both A and R are correct but R is NOT the correct explanation of A.
Analysis of Assertion A
Assertion A states that horizontal resistance is durable because it is non-race specific.
- Horizontal resistance (also known as non-specific or quantitative resistance) involves multiple genes and provides a general defense against a broad range of pathogen strains.
- Because it targets multiple pathogen functions or is based on general plant defense mechanisms, it is much harder for the pathogen to overcome quickly.
- This makes horizontal resistance generally more durable over time compared to race-specific resistance.
Therefore, Assertion A is correct.
Analysis of Reason R
Reason R states that race-specific resistance puts pressure on the pathogen to evolve more virulent races.
- Race-specific resistance (often controlled by single R genes) provides defense against particular races or strains of a pathogen that possess matching avirulence genes.
- When such resistance is deployed widely, pathogen populations that happen to have mutations allowing them to overcome that specific resistance are strongly selected for.
- This selection pressure drives the evolution of new, potentially more virulent or aggressive pathogen races capable of overcoming the host's specific defense.
Therefore, Reason R is correct.
Relationship between Assertion A and Reason R
While both statements are factually correct:
- Assertion A explains the durability of horizontal resistance based on its non-race-specific nature.
- Reason R explains a consequence (pathogen evolution pressure) associated with race-specific resistance.
- Reason R does not explain *why* horizontal resistance is durable. The durability of horizontal resistance stems from its broad-acting, multi-gene nature, not from the evolutionary pressures exerted on pathogens by race-specific resistance.
Thus, Reason R is not the correct explanation for Assertion A, even though both are true statements.
Was this answer helpful?
Similar Questions
- Which of the following is not a key feature of Basmati Rice?
- In case of resistance, the rate of reproduction of a plant pathogen will be:
- Backcross breeding method is useful for the improvement of:
- As per Hardy Weinberg Law, in a random mating population what is the frequency of AA genotypes from a cross of Aa (2pq) × Aa (2pq)?
- Arrange the order of events in the production of the phenotype by a gene.
A. Protein
B. Phenotype
C. Gene
D. RNA
Choose the correct answer from the options given below: - The word 'Agronomy' is derived from ________
- In universal soil loss equation $ A = R \times K \times LS \times C \times P $, alphabet 'K' denote for ______
- The instrument used for measuring cloud height is called as _______
- Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Farmyard manure (FYM) is a bulky organic manure
Reason R: Bulky organic manures are relatively low in nutrient content per unit quantity of the material
In the light of the above statements, choose the most appropriate answer from the options given below - Arrange the following crops in a sequence of lower to higher water requirement
A. Rice
B. Wheat
C. Pea
D. Cotton
Choose the correct answer from the options given below:
Important Questions from Miscellaneous
- Which of the following scheduler/schedulers is/are also called CPU scheduler ?
(A). Short Term Scheduler
(B). Long Term Scheduler
(C). Medium Term Scheduler
(D). Asymmetric Scheduler
Choose the correct answer from the options given below: - A situation where two or more processes are blocked, waiting for resources held by each other is called:
- External fragmentation occurs ________.
- Which disk scheduling algorithm looks for the track closest to the current head position?
- Which CPU scheduling algorithm prefers the process with the shortest burst time?
Need Expert Advice?
Upcoming Exams
GATE
February 06, 2027
Test Series
CUET
CUET PG Psychology (HUQP20) 2026 Mock Test Series
10 Tests
760 Attempts
3.7(14)
English
More Questions from CUET PG
