Plant parasitic nematodes and fungi associated with wilt disease complex of betelvine in northern Karnataka and its management

Abstract

A survey on the occurrence of root-knot disease in three major betel vine growing districts of northern
Karnataka revealed 0.0 to 87% of disease incidence. The present survey also revealed that the association Meloidogyne spp. with fungi, namely, Sclerotium rolfsii, Rhizoctonia bataticola and Fusarium solani in most of the locations surveyed. Pathogenicity of organisms (M. incognita, S. rolfsii, R. bataticola and F. solani) involved in wilt disease complex of betel vine was proved under glasshouse conditions and all of them were found to be pathogenic. Individually, S. rolfsii was the most aggressive pathogen followed by R. bataticola, F. solani and M. incognita. While combined inocula of all the four organisms (M. incognita + S. rolfsii + R. bataticola + F. solani) was more damaging than the concomitant inoculations of nematode with either of the three fungi. In an integrated management study conducted in a naturally affected betel vine garden, it was found that a combined application of an organic amendment (Enriched farmyard manure) with a biocontrol agent (Trichoderma viride) and chemicals (Carbofuran, Carboxin and Carbendazim) was found to be effective in reducing the wilt incidence, nematode population, number of galls and Competitive Saprophytic Ability (CSA) of fungi namely, S. rolfsii and R. bataticola.