Question

Citrus rootstock which is tolerant to gummosis, root rot, tristeza and drought

• A. Karna khatta
• B. Cleopatra mandarin
• C. Sweet orange
• D. Carizzo citrange

Hint:

Choosing citrus rootstocks involves matching their tolerance profile to local challenges.
Cleopatra mandarin: Good all-around tolerance to gummosis, root rot, tristeza, and drought.
Carrizo citrange: Good for Phytophthora, tristeza, nematodes; moderate drought tolerance.
Sweet orange & Karna khatta: More susceptible to some of these issues.

Answer 1

The Correct Option is B

Step 1: Sweet orange and Karna khatta are ruled out as poor matches for combined gummosis, root rot and tristeza tolerance.
Step 2: Both Cleopatra mandarin and Carrizo citrange resist Phytophthora and tristeza.
Step 3: Cleopatra mandarin additionally shows notably better drought tolerance than Carrizo citrange.
Step 4: The correct answer is Cleopatra mandarin.