Antibiotic biocontrol — Streptomyces griseochromogenes is reported to show a potent curative effect against which plant disease?

Introduction / Context:
Members of the genus Streptomyces produce many agriculturally important antibiotics. Streptomyces griseochromogenes is historically linked with an antibiotic effective against the rice blast fungus, a major pathogen of rice worldwide.

Given Data / Assumptions:

• Rice blast (caused by Pyricularia/Magnaporthe oryzae) threatens yield and requires integrated control.
• Antibiotics from Streptomyces have been explored for plant disease management.
• Blasticidin S is a well-known product associated with S. griseochromogenes.

Concept / Approach:
Blasticidin S exhibits strong activity against rice blast, making S. griseochromogenes notable in the history of plant disease control. Recognizing pathogen–antibiotic pairings is useful in agribiotech and plant pathology exams.

Step-by-Step Solution:

Verification / Alternative check:
Historical literature reports blasticidin S from S. griseochromogenes with efficacy against rice blast in paddy systems.

Why Other Options Are Wrong:

• Yellow blight of maize, soybean milo disease, and eye spot of sugarcane have different etiologies and control measures not centered on blasticidin S from this species.

Common Pitfalls:
Confusing producers of polyoxins or kasugamycin with blasticidin S; multiple Streptomyces species yield distinct antifungals.

Final Answer:
Rice blast disease (Pyricularia oryzae/Magnaporthe oryzae)