Persistency and volatile behaviour of selected chemicals in treated soil against three basidiomycetous root disease pathogens

Abstract

Four chemicals viz. tridemorph, peconazole, triadimenol and quintozene were tested for their volatile phase activity and persistency of efficacy in treated soil, and invitro fungitoxicity against Rigidoporus lignosus, Ganoderma philippi and Phellinus noxius. All the chemicals were found to be exceedingly fungitoxic invitro to the three pathogen with ED 50 values of < 1.35 μg/ml. Quintozene was relatively less toxic to the pathogens than the other three chemicals. Penconazole exhibited excellent inhibition via vapour phase activity followed by tridemorph and quintozene. Triadimenol displayed little vapour phase inhibition. Tridemorph was the most persistent maintaining its high efficacy 8 weeks after soil treatment, followed by quintozene. Penconazole and triadimenol displayed much lower efficacy during the same duration.

Keywords:

• chemical persistency
• Hevea braziliensis
• rubber root diseases
• volatile behaviour of chemical