First record of the occurrence of Pleurotus species on new hosts in Bangalore, Karnataka, India

Mushrooms have wide geographical distribution, with greatest commercial importance, both in temperate areas and tropical regions of the world. The agarics mycota of tropical eco - regions of Bangaluru, Karnataka was surveyed in different seasons from 2019 to 2020 for collection and identification of fungal samples. Detailed macroscopic and microscopic study of fungal samples was identified as Pleurotus pulmonarius (Fr.) Quél. P. ostreatus (Jack.) P. Kumm. P. populinus O. Hilber & O. K. Mill. For the first time, P. pulmonarius (Fr.) Quél was causing stem decay in Mangifera indica L. was reported from India. New host record of P. populinus O. Hilber & O. K. Mill on Spathodea campanulata was reported from India. The 3 species of Pleurotus was reported for the first time from the study area of Bengaluru, Karnataka, India .


Introduction
Tropical forests are a haven of biodiversity with richest macro-fungal diversity in the world; which supported the higher diversity in it when compared to the temperate zones (1). The number of fungal species was updated to 3.8 million from 1.5 million estimated recorded by mycologists around the world, from that only 8 % of fungal species were described; so the study of fungal diversity and systematic is required (2). Macro-fungal diversity study is required at the global level (3). The wood rotting fungi were cultivated to get bioactive compounds used as medicines in our daily life (4,20,21). Mushrooms were characterized by using different morphological characters such as shape of stipe, pileus, margin of fruit body, colour of fruit body, gills, flesh, annulus, pseudorrhiza and spore print (15). Pleurotus (Fr.) P. Kumm species is one of the mostly cultivated mushrooms in different environmental conditions and growing on different substrate materials. The fungal diversity in India is high because it has different climatic regions geographically and also different forest types, hot spots, eco-regions etc; so the conservation and domestication of fungal flora is required. Depending upon the species, the fruiting bodies of Pleurotus was showing different colours like white, cream, grey, yellow, pink and light brown. It have three parts like a flashy shell (Pileus), a short or long lateral or central stalk (stipe) and long furrows underneath the pileus (gills or lamellae) (5). Speciation of cultivated, temperate and tropical Pleurotus species was done in silico prediction method using conserved sequences (17). It was able to grow at 20 to 30 °C temperature, and produces fruiting body at 80-100% relative humidity, on different substrates of agricultural waste (6). The present study aims at preliminary diversity of Pleurotus in Bengaluru, Karnataka, India.

Study area
Bengaluru (Bangalore), a capital city of Karnataka state situated in the Mysore Plateau (a region of the larger Precambrian Deccan Plateau) at an average elevation of 920 m (3,018 ft). The Garden city (Bangalore) is showing latitudes at 12°58' and 12°97' N and longitudes at 77°34' and 77°56' E; which covers an estimated area of 741 km (286 mi) with a different types of ecosystems. The Bangalore city has tropical savanna climatic conditions with varied wet and dry seasons (18)

Phenotypical identification
A survey was conducted in different seasons from 2019 to 2020, for collection of different wood rotting fungi from SJCC tree flora. The fruiting bodies of fungal samples was collected in paper bags and brought to the lab for detailed study of macro and microscopic characters used for phenotypical identification (7,19,22,23).

Results
The collection of wood rotting fungal samples were identi-

Pleurotus populinus O. Hilber & O. K. Mill. (1993)
Sporophore: broadly convex, flat, fan-shaped, nearly circular in shape if it growing on top part of logs, KOH on surface of cap give yellowish colour, 4.8 -15 cm; upper surface: greasy shining, bald when young; whitish to pinkish gray when matures, creamish yellow when drying; the margin incurved when young, later wavy at maturity (Plate II Fig. D); lower surface: gills running down the pseudo stem, close, short-gills frequent, whitish to creamish yellow; Stalk: present when it grows on the tops of logs or branches, creamish white, slightly hairy near the base 2.

Discussion
The Karnataka state has 38284.3 km 2 forest areas which contributes 20 % its geographical area. The fungal diversity is rich in forest and urban areas of Karnataka; but these eco-regions were not studied for mushrooms diversity (8). Pleurotus salmoneostramenius (WGM-2), was found on Branch of tree in forest area of Theerthahalli Shimoga district of Karnataka, India (16). In the present study the Pleurotus species is reported from urban area of Karnataka. The Cyptotrama asprata, Hygrocybe acutoconica, H. alwisii, Oudemansiella furfuracea, Hypholoma subviride and Lactocollybia epia are reported for the first time from Karnataka State (8). In the present study the P. pulmonarius (Fr.) Quél. P. ostreatus (Jack.) P. Kumm. P. populinus O. Hilber & O. K. Mill. was reported for the first time from urban Eco-regions of Bangalore, Karnataka, India. From 8 different places in an around Bangalore like scrub jungles and urban areas; a total number of 90 fungal species was reported, which belonging to 19 families, 05 orders and 48 genera. 28 species of mushrooms were recorded for the first time from India (9). In the present survey, one Pleurotus genus with 3 species were added newly to the mushroom biodiversity of Bangalore. The different bioactivities like anticancer, antiinflammatory, antioxidant and antihyperglycemic activity of P. pulmonarius was scientifically proven (10), P. pulmonarius isolate numbers MF037415 was found on dead Mangifera indica log (11). In the present study, the P. pul-monarius was causing stem trunk decay on living tree of M. indica. P. ostreatus isolate number MF037419 was found on dead wood log of Elaeis guineensis and on wild local mango wood logs (M. indica); which is reported for the first time from Goa part of the entire Western Ghats region (12). In the present study, the P. ostreatus was isolated from the paddy straw samples used for cultivation in the SJCC, Bangalore. Earlier it was reported that P. cystidiosus from Agumbe (13), Karnataka. A single sample of oyster mushrooms was collected from Navsari district on the bark of African tulip tree (Spathodea campanulata) at a height of 1.5 m; identified as P. cystidiosus (14). In the present study, for the first time the new host record for P. populinus was reported on dead tree of tulips. All three species of Pleurotus were new record to the mushroom diversity of urban area of Bangalore, Karnataka, India.

Conclusion
Mushroom was a complete, healthy food suitable to all kind of peoples from child to old age. So the Agaricales in tropical eco-regions of Bangalore, Karnataka was surveyed in different seasons from 2019 to 2020 for collection and identification. Based on macroscopic and microscopic study of collected mushroom were identified as P. pulmonarius (Fr.) Quél. P. ostreatus (Jack.) P. Kumm