Seasonal Variation and Distribution Patterns of Endophytic Community in Withania somnifera

Abstract

Withania somnifera also known as Ashwagandha used as rasayana (tonic) in Ayurvedic system of medicine. It is widely considered as Indian Ginseng and possesses medicinal properties like adaptogenic, antistress, anxiolytic, anti-arthritic, anti-inflammatory etc. There is long history of microbes having stable symbiotic relationship with plants aiding them in growth and survival. This endophytic relationship is also been observed in medicinal plants. This study is an attempt to observe the biodiversity of endophytic fungal community in Withania somnifera and to understand their colonization. The study was aimed to isolate endophytes from different organs of Withania somnifera with seasonal variations. A total of 131 endophytic fungi were isolated from 450 explants from different organs like leaves, stems and roots of W. somnifera. The overall colonization rate of endophytes in winter, summer and monsoon were 42.67%, 7.33% and 37.33% respectively. Among the identified isolates, most abundant and frequently isolated genera were Alternaria, Fusarium and Chaetomium sps. The dominant species isolated in winter were the Fusarium moniliformae and Chaetomium globosum from leaves with 17.24% and 13.79% dominant frequency, respectively. While Alternaria raphani and Chaetomium globosum were most dominant species in summer from leaves with 40% dominant density. In the monsoon, Microsporum ferruginem was the most dominant species isolated from leaves and stem with 61.29% and 42.86%, respectively. The most recurring endophytic species of Ascomycetes group were Alternaria alternata and Chaetomium globosum seen in all seasons.