Benagi, V.I.Divya Bharathi A.R.2022-01-022022-01-022017-09https://krishikosh.egranth.ac.in/handle/1/5810180240Laboratory experiments were conducted at Department of Plant pathology, College of Agriculture, Dharwad and field experiments were carriedout under naturally infected farmer’s field at Kakol and Ranebennur of Haveri district to study the etiology and integrated management of wilt complex of betelvine (Piper betle L.). Roving survey conducted in Bagalkot, Belagavi, Davanagere and Haveri district depicted maximum wilt incidence in Davanagere district (17.2 %) during 2015-16 and in Haveri district (19.2 %) during 2016-17. The maximum disease incidence recorded in Kariyele and drumstick + Erythrina as supporting plants. Fusarium spp., Rhizoctonia bataticola, Sclerotium rolfsii and Meloidogyne spp. were major pathogens. Under variability studies, potato dextrose agar medium supported best growth of all fungal pathogens. Ten isolates of S. rolfsii, R. bataticola and 30 isolates of Fusarium spp. varied for morphological and cultural characters, the isolates of Fusarium spp. were further grouped based on their pathogenic and molecular variability. SGM-1, Swarna Kapoori, Andaman RPM and Mysore local were moderately resistant out of 20 genotypes. Under in vitro studies, non-systemic fungicide captan was effective. Systemic fungicides, hexaconazole, propiconazole and tebuconazole were effective. Carboxin 37.50 % + thiram 37.50 % and captan 70 % + hexaconazole 5 % WP were also effective. Garlic, black tulsi and turmeric extract (1:1:1) and Trichoderma harzianum (IOF isolate) was effective against all the three fungal pathogens. Adoptive module comprising of soil application of organic amendments (T. harzianum enriched Farm yard manure @ 1 kg/vine + Neem cake @ 250 g/vine), fungicides (carboxin 37.50 % + thiram 37.50 % WP @ 2.5 g/l and captan 70 % + hexaconazole 5 % WP @ 2 g/l) and nematicide (carbofuran 3G @ 100 g/vine) recorded lower disease incidence (14.57 %), highest yield (44.83 lakh leaves/ha) with the B: C ratio of 6.93:1.EnglishThesis