Endophytic fungal diversity associated with roots of Angelica glauca: An endangered medicinal plant of Northwest Himalaya

Abstract

Angelica glauca Edgew. is an endangered medicinal plant species that is known for its roots containing valuable essential oil. It is overexploited for its roots and has become endangered and nearing its threshold. This study is aimed at exploring the endophytic fungal diversity associated with its roots to further study the conservation aspects with the help of the interaction of host plant species and endophytes. About 24 different root fungal endophyte species were isolated among which Geotrichum candidum (32.03 ± 7.95 %) was found to be the most dominant followed by Fusarium oxysporum (11.49 ± 21.69 %). The average root colonization of all the endophytes in all four collection fields was 61.195 ± 9.67 % wherein the maximum colonization was observed in wild root samples (74%) and the least root colonization by fungal endophytes was observed in two years old cultivated plants root system (52.36%). Positive Pearson’s correlation (r = 0.801) was observed between the samples/fields and root colonization by fungal endophytes, indicating the colonization increases in roots as the age of plant species advances. Both the Simpson’s Diversity Index (D) and Shannon Wiener diversity index (H) indicate relatively lower diversity in Field 3 (D = 0.43 & H = 1.07) and Field 4 (D = 0.57 & H = 0.97) i.e. in two years old plantations and wild plants. Menhinick Index (Dmn) and Margalef Richness Index (Mf) are based on species richness, and both of them indicate Field 3 (Dmn = 0.95 & Mf = 2.04) to be the richest. Both Buzas and Gibson’s Index (E) and Equitability Index (EH) are a measure of evenness and yield similar results viz. Field 1 (one year old plantations) (E = 0.65 & EH = 0.76) and Field 4 (E = 0.66 & EH = 0.70) being the most even in terms of species distribution. Berger-Parker Dominance Index (B) shows field 3 (B = 0.75) having the highest values.