Investigations on magnitude and symptomatology of newly invasive leaf spot and tip blight of Nandi (Lagerstroemia lanceolata Wall.)

Abstract

Leaf spot and tip blight of Lagerstroemia lanceolata, two new invasive foliar diseases pose a serious threat to the quality planting stock production. Investigations were done in three eco-climatic zones of Canara circle (i.e., plain, hilly and coastal of Uttara Kannada district) revealed the incidence positivity of both the diseases in all nine nurseries surveyed. Maximum mean leaf spot incidence was in hilly zone (DI- 85.46%; PDI- 69.55) and coastal zone had highest tip blight (DI- 76.71; PDI- 59.49). The leaf spot disease induced seedling mortality was dominated by Kyadagi nursery in hilly zone (32.37%) and Sharavathi nursery (coastal zone) for tip blight disease (37.21%). The distinct leaf symptoms were red circular spots covered by a yellow halo. Similarly, tip blight showed white cottony growth on lower and corresponding yellow symptoms on upper leaf lamina.