Molecular Identification of <i>Alternaria alternate</i> (Fr.) Keissl. from the Leaf Blight Disease of <i>Centella asiatica</i> L.

Abstract

Centella asiatica (L.), frequently known as Thankuni, is an important ethnobotanical plant in Bangladesh. This study was conducted to evaluate the morphological characteristics, cultural factors and molecular identification of the causal agent of Alternaria leaf blight disease of C. asiatica. The potato dextrose agar (PDA) medium recorded the maximum mycelial growth (69 mm), followed by the yeast extract agar (YEA) medium, while the honey peptone agar (HPA) medium recorded the lowest growth (27 mm). The optimal pH and temperature for mycelial growth of Alternaria alternata were 6 and 30°C, respectively. Internal transcribed spacer (ITS) region of Alternaria alternata PCR products measured 558 bp and blast search showed 99% sequence similarity with Alternaria alternata species complex. To the best of our knowledge, Alternaria leaf blight disease caused by Alternaria alternata is the first record in Bangladesh.