Macrofungi in the lateritic scrub jungles of southwestern India

Acknowledgements: Authors are grateful to Mangalore University for permission to carry out this study in the Department of Biosciences. One of us (GAA) acknowledges the award of INSPIRE Fellowship, Department of Science and Technology, New Delhi, Government of India (Fellowship # IF140953). KRS is grateful to the University Grants Commission, New Delhi, India for the award of UGC-BSR Faculty Fellowship. We thank N. Karun Chinnappa, Sudeep D. Ghate (Department of Biosciences) and Keshava Chandra (Department of Applied Botany) for stimulating discussions. Abstract: A pilot study on macrofungi in scrub jungles (with and without fire-impact) in lateritic region of southwestern coast of India was carried out. Out of 11 species in 10 genera recovered, six and five species were confined to scrub jungle and fire-impacted scrub jungle, respectively. An ectomycorrhizal Amanita sp. was the most frequent in scrub jungle associated with exotic (Acacia auriculiformis and A. mangium) and plantation (Anacardium occidentale) trees. Based on traditional knowledge, it is a highly edible and nutritional delicacy in the coastal regions. Astraeus odoratus was another common ectomycorrhizal fungus in native trees Hopea ponga, which was recovered from the fire-impacted scrub jungle and is possibly edible. Edible termite mound mushroom Termitomyces striatus was also common in the fire-impacted scrub jungle. Chlorophyllum molybdites was the most frequent mushroom in the fire-impacted scrub jungle.

Macrofungi have a wide dimension in different ecosystems involving in plant detritus decomposition, nutrient cycle, pathogenesis and mutualistic association with a wide variety of tree species. Nowadays, macrofungi have become a centre of attraction for research due to their edible, ectomycorrhizal, medicinal, toxic and hallucinogenic properties. Global estimates of macrofungi based on plant/macrofungal ratio ranges between 53,000 and 110,000 (Mueller et al. 2007). Up to 850 macrofungi have been reported mainly from the Himalayan and Western Ghats regions of India (Manoharachary et al. 2006). Recent checklists documented 616 and 178 species (in 112 and 68 genera) of agarics from the Western Ghats of Kerala and Maharashtra states, respectively (Farook et al. 2013;Senthilarasu 2014). A recent illustrated monograph encompasses descriptions of 330 species (in 166 genera and 51 families) from the state of Kerala (Mohanan 2011).
The southwestern coast of India predominantly consists of lateritic soil, which harbours a variety of herbs, shrubs and tree species. These scrub jungles are prone to fire during summer (February-May). Relatively, studies on macrofungi in lateritic regions of the western coast are scanty (e.g., . Similar to the lateritic belt of southwestern India, lateritic regions of the eastern part start from Chota Nagpur plateau and extend up to Bihar, Odisha, Chhattisgarh, Jharkhand and West Bengal (Manna & Roy 2014). A wide variety of macrofungi have been reported from the lateritic part of eastern India especially form plantation: Anacardium occidentale).
Hygrocybe astatogala and Lepiota sp. were also common in scrub jungle. The other three rare species include Hygrocybe aurantioalba, Phellinus sp. and Ramaria versatilis. Out of five mushrooms in the fire-impacted region, Chlorophyllum molybdites was frequent, while Astraeus odoratus (ectomycorrhizal in native tree species, Hopea ponga) and a termite mound fungus Termitomyces striatus were common. The other two species Agaricus crocopeplus and Nectria cinnabarina were rare. Brief descriptions of macrofungi in scrub jungle as well as the fire-impacted region of scrub jungle are provided.
Occurrence and distribution: Frequent in early monsoon in scrub jungle (June and early July) in the present study. Recorded in coastal sand dunes near Mangalore (Ghate et al. 2014)  Jharkhand, Odisha and West Bengal (e.g., Pradhan et al. 2010Pradhan et al. , 2012Pradhan et al. , 2013Hembrom et al. 2014;Manna & Roy 2014). Several tribals are dependent on the edible and medicinal macrofungi for their livelihood during the wet season (Pradhan et al. 2010;Manna & Roy 2014). Due to scanty studies on macrofungi in the lateritic regions of southwestern India, a pilot study was undertaken.

Study area and Observations
A survey was carried out in scrub jungle and fireimpacted scrub jungle in Konaje Village (90m elevation), adjacent to Mangalore University Campus (Dakshina Kannada District, Karnataka) (12 0 49'N & 74 0 55'E). West facing elevated slopes possess patchy scrub jungles as it is highly influenced by strong winds. In addition, these scrub jungles often face threat of fire during summer. Several native tree species (e.g., Careya arborea, Holigarna sp., Hopea ponga, Macaranga peltata, Sapium insigne, Syzygium cumini and Terminalia paniculata), exotic tree species (e.g., Acacia auriculiformis and A. mangium) and plantation tree species (Anacardium occidentale) dominate this region. In addition, open places are occupied by grasses (Heteropogan contortum, Pennisetum polystachyon and Themeda tremula) and a dominant weed Eupatorium odoratum. The floor of the jungle has predominantly rocky escarpments with loamy, sandy, gravel, pebble-rich lateritic soil.
The survey was carried out employing opportunistic mode of sampling during monsoon (June-August 2014). Macro-and micro-morphological features of macrofungi recovered in the scrub jungle and fire-impacted scrub jungle were documented and their characteristics were compared with literature for identification (Sathe & Daniel 1980;Sathe & Deshpande 1980;Jordan 2004;Phosri et al. 2004;Phillips 2006;Mohanan 2011;Hembrom et al. 2014). Field photographs (Sony DSC-HX100V and Nikon D40) and microscopic photographs (Olympus CX41RF) were obtained. Macrofungi collected were preserved in the herbarium (Department of Biosciences) by transferring blotted specimens on to a fixative (water-ethanol-formaldehyde: 14:5:1) in airtight containers.
Fresh weight of mature fruit bodies 0.43g (0.4-0.5 g) (n=4). Substrate: Found in lawn soil, where the soil is rich in moisture and humus.
Fresh weight of mature fruit bodies 0.34g (0.3-0.4 g) (n=12). Substrate: usually found in soil, requires high moisture content humus soil. It is also found in non-fire regions including botanical gardens other than study area.
Occurrence and distribution: Rare in scrub jungle in the present study. Recorded in different locations of Kerala (Chandhakkunnu & Nilambur) (Mohanan 2011).
Fresh weight of mature fruit bodies 6.1g (5.4-6.6 g) (n=5). Substrate: Found usually in pebble-rich laterite soil or the soil accumulated adjacent to the rocks with charcoal and ash debris (Image 3A,B).
Occurrence and distribution: Common in fire-impacted scrub jungle in early monsoon as ectomycorrhizal with native tree species (Hopea ponga) in the present study (note charcoal debris in Image 3D). Recorded in different locations of Kerala (Nilambur and Sholayar) (Mohanan 2011). It has also been reported from Jharkhand (Rajmahal Hills, sacred grove of Mandro fossil park and forests of Dalahari Village) consists mainly scrub vegetation and likely ectomycorrhizal in forest tree species Shorea robusta (Hembrom et al. 2014).
Fresh weight of mature fruit bodies 5.19g (2-7.4 g) (n=7). Substrate: In coarse soil usually they are found gregariously under bright sunny areas.
Fresh weight of mature fruit bodies bodies 0.14g (0.1-0.24 g) (n=20). Substrate: on the dying wood log or twig. As the fruiting body matures, the wood log or twig decomposes gradually.
Fresh weight of mature fruit bodies 10.6g (9.3-15.4 g) (n=10). Substrate: On termite mounds, usually these mounts ll are buried in soil thus the specimen appears embedded in the soil.

Discussion
Compared to the western lateritic region of India, extensive studies have been conducted on macrofungi in the laterite plateau in the eastern region of India (e.g., Pradhan et al. 2010Pradhan et al. , 2012Pradhan et al. , 2013Manna & Roy 2014). A variety of ecotomycorrhizal, bryophilous, lignicolous, humicolous, coprophilous, termitomycetes, saprotrophic and parastitic macrofungi have been reported (Pradhan et al. 2012(Pradhan et al. , 2013. Nearly 4-29 % of macrofungi in eastern lateritic region are ectomycorrhizal especially in forest tree species Shorea robusta (Pradhan et al. 2012(Pradhan et al. , 2013. A variety of mushrooms were harvested as nutritional and as a medicinal source by the ethnic groups for their livelihood (Pradhan et al. 2010(Pradhan et al. , 2012(Pradhan et al. , 2013Manna & Roy 2014). Up to 30 species of wild edible macrofungi have been recognized in the laterite plateau in the eastern part of India, out of them 10 species are widely consumed and marketed (Manna & Roy 2014).
In our study two species were frequent or common ectomycorrhizal (Amanita sp. and Astraeus odoratus) in different tree species and interestingly both of them are traditionally edible in the immature stage. However, there is a mixed opinion on the edibility of A. odoratus among the coastal dwellers. Besides these mushrooms, highly edible Termitomyces striatus was also common especially in fire-impacted scrub jungle. Amanita sp. (also called 'motte anabe' in Kannada: meaning 'egg mushroom') exists in immature stage underneath the lateritic soil or coastal sand dunes (Ghate et al. 2014). In slightly advanced stage, it becomes dumbbell shaped (bulbuous base with bulbous cap with intact or partially teared universal vail). Egg and dumbbell stages are most edible according to traditional knowledge of the coastal dwellers.
In summary, this pilot study resulted in the occurrence of 11 macrofungi in the lateritic scrub jungle of southwest India. According to traditional knowledge, three species (Amanita sp., Astraeus odoratus and Termitomyces striatus) were edible. Out of them Amanita sp. and A. odoratus were ectomycorrhizal in native and exotic tree species and T. striatus was termite mound dependent. All these species are common or frequent in scrub jungle or fire-impacted scrub jungle. Further attention is warranted to assess the lateritic coastal biomes of southwestern India in search of edible and ectomycorrhizal macrofungi as alternative nutritional source, medicinal source and future silvi-culture. More specific attention needs to be focused on the impact of fire on macrofungi in lateritic scrub jungles along the west coast of India.