Morphological and Molecular Characterization of Lasiodiplodia Theobromae Causing Crown Rot of Banana

Abstract

Crown rot of banana caused by Lasiodiplodia theobromae is a serious post harvest problem leads to severe yield reduction. In survey, Negamam in Coimbatore district showed highest incidence of crown rot (62.0%). Among the varieties surveyed, Rasthali showed higher incidence than Poovan. Among the different methods tested, pin prick method recorded the maximum per cent disease index of about 80.91% by the isolate Lt_8. L. theobromae produces grey, grayish black and medium grey mycelium. Lt₈ produces maximum mycelium growth whereas Lt₇ produces least mycelia growth. Excellent pycnidial production was observed in Lt₈ whereas poor pycnidial production was observed at Lt₇