PHILIPP AGRIC SCIENTIST Vol. 96 No. 4, 411–418 December 2013
ISSN 0031-7454
Lentinus squarrosulus and Polyporus grammocephalus: Domesticated, Wild Edible Macrofungi from the Philippines
Newly
Angeles M. De Leon1,2,*, Renato G. Reyes2 and Thomas Edison E. dela Cruz1,3 1
The Graduate School, University of Santo Tomas, España 1015, Manila, Philippines Department of Biological Sciences, College of Arts and Sciences, Central Luzon State University, 3120 Science City of Muñoz, Nueva Ecija, Philippines 3 Department of Biological Sciences, College of Science, University of Santo Tomas, España 1015, Manila, Philippines * Author for correspondence; e-mail:
[email protected] 2
Portion of the dissertation of the corresponding author. Funded by the Commission on Higher Education (CHED) and the Department of Science and Technology (DOST) - Accelerated Science and Technology Human Resource and Development Program Dissertation Grant. Lentinus squarrosulus and Polyporus grammocephalus are wild, edible macrofungi utilized as food by the indigenous Aeta tribes in Botolan, Zambales, Philippines. Domestication of these wild edible species is thus necessary to render these fungi available all year round for food and other purposes. In this study, different locally available culture media from natural sources, grain spawning materials and bagged substrates, with combinations of rice straw and sawdust formulations, were evaluated for the mycelial growth and fructification of these two edible macrofungi. Results showed that secondary mycelial growth was observed best on coconut water-gelatin medium. Sorghum seeds and/or corn grits also yielded very luxuriant mycelial growth at the shortest incubation period of 6 d for L. squarrosulus and 7 d for P. grammocephalus. Rice straw-sawdust formulation (g) at 100:400 had the highest biological efficiency (7.83%) in L. squarrosulus. In contrast, rice strawsawdust formulation (g) at 400:100 had the highest biological efficiency (2.91%) in P. grammocephalus. Both L. squarrosulus and P. grammocephalus are new additions to the record of successfully domesticated wild edible macrofungi in the Philippines.
Key Words: edible macrofungi, fruiting body production, grain spawns, Lentinus squarrosulus, mushroom culture, mycelial growth, Polyporus grammocephalus Abbreviations: CDG – corn grits decoction gelatin, CWG – coconut water gelatin, PDA – potato dextrose agar, PSG – potato sucrose gelatin, RS – rice straw, SD – sawdust
INTRODUCTION Mushroom production in the Philippines started in 1930 with the introduction of Volvariella volvacea (Bull.: Fr.) Singer as the first commercially cultivated mushroom species (Reyes et al. 2009b). Since then, mushrooms are seen as a major crop in the country’s local markets. In Makati City, for instance, mushrooms are among the fast-selling items in the vegetable section of several supermarkets (Barriga 2010). However, very few species of mushrooms are grown for commercial purposes in the country. Some of the locally cultivated mushrooms are V. volvacea, Ganoderma lucidum P. Karst., Auricularia auricula (Hook. F.) Underw., and several species of Pleurotus and Lentinus (Reyes et al. 2009b). Most of these cultivated mushrooms are also imported species. Their production technology is based on the country of The Philippine Agricultural Scientist Vol. 96 No. 4 (December 2013)
origin of the mushroom, and is only adapted locally. Mushroom cultivation in the Philippines thus requires utilization of local materials for mass production. In addition, the country’s tropical climate favors the growth of many wild and edible fungi. Many of these species await discovery for their potential uses as medicine or as food. If properly harnessed, these wild and edible fungal species can also be used to generate livelihood among local communities and ensure food security (Reyes et al. 2009b). To date, a number of wild edible macrofungi, e.g., Schizophyllum commune Fr. (Bulseco et al. 2005), Coprinus comatus (O.F.Müll.:Fr.) Pers. (Reyes et al. 2009b), Collybia reinakeana P. Henn. (Reyes et al. 1997), Lentinus sajor-caju Fr. (Cuevas et al. 2009) and Lentinus tigrinus (Bull.) Fr. (Dulay et al. 2012) were successfully domesticated in the country.
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Wild Edible Macrofungi Lentinus squarrosulus and Polyporus grammocephalus
Lentinus squarrosulus (Mont.) Singer is a highly prized mushroom. In Nigeria it is appreciated for its meaty taste and texture (Kadiri 2005). Many researchers focused on the development of technology for the cultivation of this species. Kadiri and Arzai (2004) successfully cultivated fruiting bodies of L. squarrosulus on composted and non-composted agricultural wastes and wood logs of tropical hardwood plants. The mushroom was also cultivated on cassava peel, rice straw and Andropogon straw as well as on the bark of Spondias mombin (Adesina et al. 2011). In addition, Oghenekaro et al. (2009) cultivated L. squarrosulus on sawdust of five economically important tropical tree species. The fungus is known to produce lignin and cellulosedegrading enzymes (Wuyep et al. 2003), hence, its reported cultivation in many lignin-rich and celluloserich substrata. Compared with the many studies done on L. squarrosulus, none has been done on Polyporus grammocephalus Berk. in terms of its mass cultivation. This fungus is also claimed to have medicinal properties. Thus, this study is the first report of the cultivation of P. grammocephalus. Both L. squarrosulus and P. grammocephalus were successfully grown and their fruiting bodies were produced. Locally available substrate media were evaluated for the mycelial growth and fructification of these two edible macrofungi.
MATERIALS AND METHODS Source of Mushroom Species Fruiting bodies of L. squarrosulus and P. grammocephalus were initially collected from the mountains of Botolan, Zambales, Philippines. Fruiting bodies were scraped from the bark of trees, wrapped in wax paper, coded and brought to the laboratory. General characteristics of the collected macrofungi as described by Kuo (2006) and Tun (1992) were as follows: Lentinus squarrosulus: Cap 1.5–10 cm across, convex to convex-depressed to funnel-shaped, with a somewhat wavy, ragged margin; at first, white to brown at maturity. Gills decurrent, crowded, narrow, white to yellowish white with ragged edges. Stipe 20–60 × 4–l0 mm, central to eccentric, tapering downward and often bent, hairy to scaly, creamy partial veil leaves a slight ring or zone toward the top of the stem, which may disappear in age, or veil may remain intact, covering the gills. Pileus thin, tough, fibrous, white. Odor mild or none. Taste not distinctive. Spores narrowly cylindric, smooth, nonamyloid, 6–9.5 × 2.5–3.5 µm. White spore print. Grows singly or more commonly in groups or clusters on water-soaked hardwood logs or stumps (Kuo 2006).
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Polyporus grammocephalus: Annual basidiomata, solitary, pileate, dimidiate, flabelliform or spathulate and laterally attached with a stipe-like contracted base, up to 5 cm wide and long, 3 mm thick at the base. Pileus glabrous, ochraceous to tan or pale brown with numerous fine radial lines becoming more tufted toward the base. Margin thin and deflexed in dried specimens. Stipe short or absent. Pore surface, tan to pale brown in old specimens, pores thin-walled and angular, sometimes slightly split, 2–4 mm, tubes up to 3 mm thick. Context 1–2 mm thick, cream to ochraceous, homogenous. Hyphal system dimitic, generative hyphae with clamps, 2–4 µm wide, binding hyphae of the Bovista type abundantly present, thick-walled to solid, up to 10 µm thick at the main trunk. Basidiospores oblong ellipsoid, thin-walled, hyaline and smooth, 6–8 × 2.5–3.5 µm. Spores cylindrical, smooth, 9–11 × 3–3.5 µm. White spore print. Grows over on dead wood (Tun 1992). Voucher specimens of these collected fungi were deposited at the Center for Tropical Mushroom Research and Development at the Central Luzon State University (CLSU), Muñoz, Nueva Ecija, Philippines. Isolation into Pure Mycelial Culture Collected fruiting bodies of L. squarrosulus and P. grammocephalus were tissue-cultured in the laboratory. Initially, inner tissues (5 mm × 5 mm) were cut and laid on the center of the petri dishes pre-filled with 15 mL potato dextrose agar (PDA). The cultures were then incubated at room temperature until the medium was totally covered by the mycelia of L. squarrosulus and P. grammocephalus. Pure cultures were obtained by subculturing the previously prepared tissue culture into newly prepared PDA plates. Assessment of Mycelial Growth on Indigenous Culture and Grain Spawning Media Preparation of indigenous culture and grain spawning media. Locally available culture media, i.e., potato sucrose gelatin (PSG), corn grit decoction gelatin (CDG) and coconut water gelatin (CWG), were used to evaluate the growth of L. squarrosulus and P. grammocephalus on indigenous culture media. To prepare PSG, 250 g of peeled potato was cut into cubes and boiled in 1 L of distilled water until tender. After boiling, the decoction was strained to remove the cubed potatoes. The decoction was reconstituted to 1 L by adding distilled water. Twenty grams of unflavored gelatin and 10 g of sucrose were dissolved into the decoction over low-heat fire with constant stirring. For CDG, 50 g of corn [Zea mays (Schrad.) H. H. Iltis] grits were boiled in 1 L of distilled water. After boiling, the decoction was strained, and then water was added to make up a liter. Twenty grams of unflavored gelatin and 10 g of sucrose were The Philippine Agricultural Scientist Vol. 96 No. 4 (December 2013)
