Which type of fungicide is effective on Fusarium rots?

Triadimenol is a systemic fungicide that is known to be effective against a variety of fungal pathogens, including those that cause Fusarium rots. Its mode of action involves inhibiting sterol biosynthesis in fungal cells, which is crucial for maintaining cell membrane integrity. By targeting this specific process, triadimenol prevents the growth and reproduction of fungi such as Fusarium, thereby reducing the incidence of diseases these pathogens cause in plants.

The other options listed do not target Fusarium effectively. PCNB is more traditionally used for other soil-borne diseases and may not be as effective on Fusarium rots specifically. Thiram is a contact fungicide primarily effective against other pathogens but does not have significant activity against Fusarium rots. Streptomycin is an antibiotic rather than a fungicide and is used mainly against bacterial diseases, making it unsuitable for fungal pathogens like Fusarium.