Correct option is B
Explanation:
A. edr1
Protein type: b. Raf-like MAPKKK
Race-specific nature: ii. no
edr1 is associated with enhanced disease resistance and works by encoding a Raf-like MAPKKK. The resistance is not race-specific, which means it confers resistance to multiple races. Therefore, A-b-ii is correct.
B. mlo
Protein type: d. plant-specific seven transmembrane helices protein
Race-specific nature: ii. no
mlo provides resistance to powdery mildew by encoding a seven-transmembrane helices protein. This resistance is non-race-specific, providing broad-spectrum protection. Thus, B-d-ii is correct.
C. xa5
Protein type: a. subunit of the general transcription factor TFIIA
Race-specific nature: i. yes
xa5 provides resistance against Xanthomonas oryzae and is involved in race-specific resistance. It encodes a subunit of the transcription factor TFIIA, which is part of the signaling machinery that confers this specific resistance. Therefore, C-a-i is correct.
D. xa13
Protein type: c. a member of the NODULIN3 gene family of SWEET proteins
Race-specific nature: i. yes
xa13 is involved in resistance to Xanthomonas oryzae, encoding a member of the NODULIN3 gene family of SWEET proteins. This resistance is race-specific, so D-c-i is correct.
Conclusion:
A-b-ii: edr1 → Raf-like MAPKKK → non-race-specific
B-d-ii: mlo → seven transmembrane helices protein → non-race-specific
C-a-i: xa5 → TFIIA subunit → race-specific
D-c-i: xa13 → NODULIN3/SWEET protein → race-specific
Thus, the correct answer is Option 2: A-b-ii, B-d-ii, C-a-i, and D-c-i.
