Question:
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Deformed flowers and browning of throat are major disorders of orchids.
Reason R: These disorders of orchids occur due to low temperature and chilling injury.
In light of the above statements, choose the most appropriate answer from the options given below:
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Deformed flowers and browning of throat are major disorders of orchids.
Reason R: These disorders of orchids occur due to low temperature and chilling injury.
In light of the above statements, choose the most appropriate answer from the options given below:
Assertion A: Deformed flowers and browning of throat are major disorders of orchids.
Reason R: These disorders of orchids occur due to low temperature and chilling injury.
In light of the above statements, choose the most appropriate answer from the options given below:
Show Hint
Physiological disorders are often caused by "too much" or "too little" of an abiotic factor (water, light, temperature). Chilling injury is the most common cause of flower spoilage in tropical orchids.
Updated On: Aug 13, 2026
- Both A and R are correct but R is NOT the correct explanation of A
- Both A and R are correct and R is the correct explanation of A
- A is correct but R is not correct
- A is not correct but R is correct
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Understanding the Concept:
Orchids are mostly tropical or subtropical plants. They are sensitive to environmental extremes, particularly cold, which can manifest as physiological disorders rather than infectious diseases.
Step 2: Detailed Explanation:
Assertion A Analysis: Deformed flowers (where petals/sepals are twisted or fail to open correctly) and browning of the throat/lip are indeed classic physiological disorders observed in orchids, especially in commercial varieties like Cymbidium and Dendrobium.
Reason R Analysis: Most cultivated orchids originate from regions where temperatures rarely drop below \(10-15^{\circ}C\). If the temperature drops below their tolerance limit (chilling), it disrupts the metabolic processes during bud development. This leads to the death of cells in sensitive tissues (like the throat), resulting in browning (necrosis) and structural abnormalities (deformity) as the flower continues to grow. Since the cold temperature directly causes these specific symptoms, the reason correctly explains the assertion.
Step 3: Final Answer:
Both A and R are correct, and R is the correct explanation of A.
Orchids are mostly tropical or subtropical plants. They are sensitive to environmental extremes, particularly cold, which can manifest as physiological disorders rather than infectious diseases.
Step 2: Detailed Explanation:
Assertion A Analysis: Deformed flowers (where petals/sepals are twisted or fail to open correctly) and browning of the throat/lip are indeed classic physiological disorders observed in orchids, especially in commercial varieties like Cymbidium and Dendrobium.
Reason R Analysis: Most cultivated orchids originate from regions where temperatures rarely drop below \(10-15^{\circ}C\). If the temperature drops below their tolerance limit (chilling), it disrupts the metabolic processes during bud development. This leads to the death of cells in sensitive tissues (like the throat), resulting in browning (necrosis) and structural abnormalities (deformity) as the flower continues to grow. Since the cold temperature directly causes these specific symptoms, the reason correctly explains the assertion.
Step 3: Final Answer:
Both A and R are correct, and R is the correct explanation of A.
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