First report of lasiodiplodia theobromae causing shoot blight of ricinodendron heudelotii seedlings in Cameroon - (IJAAR)

Abstract

The aim of this study was to identify the pathogen responsible to shoot blight, a new disease observed on Ricinodendron heudelotii seedlings in Cameroon. Isolation of the fungus from infected tissues was made on potato dextrose agar (PDA) milieu. After identification based on morphological characteristics (mycelium structure and conidia sizes), DNA was extracted and submitted to molecular analysis. The sequences obtained from rDNA were identified as Lasiodiplodia theobromae. Inoculums were then prepared and Koch´s postulate was verified both on detached leaves and seedlings by inoculating healthy detached leaves and seedlings with 5 mm diameter mycelia plugs and a solution of 106 conidial/ml respectively. Shoot blight symptoms were observed both on detached leaves and on seedlings. This was the first report of L. theobromae causing shoot blight on R. heudelotii seedlings.