INFLUENCE OF TOPOGRA THE INCIDENCE AND SE parasiticus Karst.) DISEASE OF TEA IN CH INFLUENCE OF TOPOGRAPHY AND SHADING COND THE INCIDENCE AND SEVERITY OF RED RUST ( DISEASE OF TEA IN CHITTAGONG REGION PHY AND SHADING CONDITION ON (Cephaleuros ITTAGONG REGION

Abstract

A survey was conducted on the incidence and severity of red rust disease of tea (Cephaleuros parasiticus Karst.) in different tea estates of Chittagong region during April to July 2014. The surveyed areas included in this study were Mohammod-nagar tea estate (Narayonhat), Datmara tea estate (Datmara), Karnafuli tea estate (Lelang), Neptune tea estate (Narayonhat), Koiyachhora tea estate (Vuzpur-Manikchhari), New Datmara tea estate (Datmara), Panchabati tea estate (Haroalchhari), Ramgarh tea estate (Ramgarh-Baganbazar), Rangapani tea estate (Rangamatia), Baromasia tea estate (Subail). Disease incidence varied from 51% to 64% and disease severity varied from 12% to 17%, respectively in different tea estates. The highest (64.33%) disease incidence was found in Baromasia tea estate and the lowest (51.67%) in New Datmara tea estate. Disease incidence and severity was moderately affected by different topographical conditions like hill, hillock and flat areas. Comparatively lower amount of disease was observed in hill areas as compared to hillock and flat areas of different tea estates. The average red rust disease incidence in hill areas was 56.90%, whereas in hillock and flat areas it was 60.13% and 61.47%, respectively. Furthermore, significant variation in disease reaction was found in shaded and un-shaded areas. In shaded areas disease incidence was 57.67% and in un-shaded areas it was 61.60%.