Fungal foliar diseases of Rauwolfia serpentina in wild, its seasonal occurrence, seed transmission and disease management.

Rauwolfia serpentinais an important medicinal herb. Studies were conducted to determine causal organisms of foliar diseases inR. serpentinain Bhadra Wildlife Sanctuary during 2006–2009. The foliar disease incidence and its distribution and disease severity in nine state forest regions of the sanctuary were determined. The seedborne nature and transmission of the causal organism was also determined. The management of seedborne inoculum was done by seed dressing with fungicides. The effect of foliage infection on secondary metabolite content was also determined. Results of the present study indicated thatCercospora rauwolfiaeis major leaf spot disease causing pathogen. The disease is homogeneously distributed through the study area. The foliar disease severity was high in Kagemanegiri forest during October–November. The minor leaf spot disease caused byAlternaria alternataoccurred occasionally.Alternaria alternatais seedborne and seed transmitted and could be managed by seed treatment with Captra or Hyzeb. The secondary metabolites like alkaloids and steroids decreased with increase in foliar infection byC. rauwolfiae, while phenol and flavonoid contents increased. The study suggested thatR. serpentinais affected in wild byC. rauwolfiaeandA. alternata. The latter pathogen is seedborne and seed transmitted and controlled by seed treatment. [ABSTRACT FROM PUBLISHER]