Mycobiology 31(3): 145-150 (2003) Copyright 2003 by The Koren Society of Mycology Chrcteriztion of Fruitbody Morphology on Vrious Environmentl Conditions in Pleurotus ostretus Kb-Yeul Jng, Chng-Sung Jhune, Jeong-Sik Prk, Soo-Muk Cho 1, Hng-Yeon Weon, Jong-Chun Cheong, Sun-Gyu Choi nd Je-Mo Sung 2 Div. of Applied Microbiology, Ntionl Institute of Agriculturl Science nd Technology, R.D.A., Suwon 441-707, Kore 1 Div. of Agriproduct Science, Ntionl Institute of Agriculturl Science nd Technology, R.D.A., Suwon 441-707, Kore 2 Deprtment of Environmentl Biology, Kwngwon Ntionl University, Kwngwon 360-763, Kore (Received August 12, 2003) This study investigted the morphologicl differences of P. ostretus grown in the rtificil environmentl conditions such s humidity, temperture, ventiltion, nd wtering. Oyster mushroom, which ws cultivted on rtificil environmentl condition, ws shown to hve different morphology of fruitbodies. The optimum CO 2 concentrtion for good morphology of P.ostretus ws 0.3%. But most fruitbody showed the morphologiclly low qulities in more thn 0.5% of CO 2 concentrtion. In the humidity in excess of 80% t 13~16 o C, the best morphology of P. ostretus ws investigted. The growth of fruitbodies of P. ostretus in the ventiltion system ws good t the wind velocity rnging from ~0.5 fpms nd expouring type. In other conditions, P. ostretus generlly showed the morphology closing to mlformtion. KEYWORDS: Morphologicl chrcteristics, Pleurotus ostretus, Ventiltion system Asins hve populrly consumed Pleurotus ostretus, nd the demnd for it hs incresed ech yer. In Kore, P. ostretus hs been cultivted for mny yers since rtificil cultivtion methods were developed in 1980 s (Ch et l., 1989). Its productivity occurring lmost 51% in Kore nd 2% in the world trends to increse s 72,348 metric tons in the re of 7,085,615 m 2 in Kore (Ministry of Agriculture & Forestry, 2003). Despite this increse, the production qulity is rther limited becuse ntionl mushroom cultivtion houses were not enough to control environmentl conditions for mushroom cultivtion. Environmentl conditions, however, were very importnt fctors to the mushroom s growth nd ing. The environmentl fctors s temperture, humidity, gses, light nd ventiltion ffect the shpe nd yield of mushroom (Lmbert, 1933; Donld, 1963; Flegg, 1978; Rudskoski, 1982; Sohi, 1989). Pul et l. (1983) reported tht high gses produce long stems nd smll undeveloped cps in Agricus brunnescens nd P. ostretus. Abnorml fruitbodies of P. ostretus in experiment developed under tretment with c. 6,000 ppm CO 2 (Kinugw, 1986). But there were few written reports relted to environmentl fctors ffecting mushroom morphology within our country. This experiment determined in terms of shpe, morphology, nd yield, the effects of temperture, reltive humidity, nd CO 2 concentrtion. The results of this study would serve s useful guide in the mss cultivtion of this mushroom in Kore nd other countries. *Corresponding uthor <E-mil: pdveg@up.nic.in> Mterils nd Methods Strin. Protoplst fusion products of Pleurotus ostretus, ASI 2180, ws obtined from the Ntionl Institute of Agriculturl Science nd Technology, Rurl Development Administrtion (RDA). The culture ws incubted on Potto Dextrose Agr (PDA) t 25 o C (Yoo et l., 1993). Substrtes. The cotton wstes nd pddy strws were used for substrtes to investigte mycelil growth of P. ostretus on different CO 2 concentrtions. To investigte morphologicl differences of P. ostretus on different CO 2 concentrtions, the poplr swdust with rice brn 20% ws used, put into 1,000 ml-polyethylene bottles, nd sterilized t 121 o C for 90 minutes. Two or three spoonfuls of precultured mother spwn in the swdust medium were inoculted to the swdust culture medium in 1,000 mlpolyethylene bottles. The inoculted swdust medi were incubted t 25 o C for 30 dys nd then induced pin-heding in the experimentl conditions. Cotton wstes were used for substrtes to investigte morphologicl differences of P. ostretus on different temperture nd reltive humidity. Its moisture content ws djusted to bout 67% by wtering. Then ech mixed substrtes of 5 kg were put into 1.78 m 2 -box. The substrtes were psteurized t 60~65 o C for six hours nd were fermented from 50~55 o C for three dys in the fermenting room. The substrtes were inoculted by precultured spwn of 500 g nd incubted t 25 o C. After bout 20 dys of incubtion, grownup substrtes were moved to the mushroom cultivtion houses which were controlled by vrious temperture nd 145
146 Jng et l. for regulr primordil formtion nd covered with newsppers for mintennce of high humidity. Immeditely fter primordil formtion, CO 2 gses in the concentrtion of 0.03, 0.1, 0.3, 0.5% flowed continuously in the growth chmbers. Then temperture ws djusted to 13~ 16 o C with cold wter supplied by the copper pipe lying in the growth chmber. To mintin high humidity dmp bsorbent cotton ws plced. Morphologicl chrcteristics of P. ostretus on different temperture nd reltive humidity. To investigte the morphologicl chrcteristics of P. ostretus on different tempertures nd reltive humidity, temperture of mushroom cultivtion house ws djusted to 13~16 o C nd 16 o C or more, nd reltive humidity ws djusted to 60% or less, 60~80%, nd 80% or more. Fig. 1. CO 2 concentrtion controlling pprtus for the mycelil growth of P. ostretus. reltive humidity. Mycelil growth of P. ostretus by CO 2 levels. The mycelil growth of P. ostretus ws mesured using the CO 2 concentrtion controlling pprtus (Long, 1969). Nmely, cotton wstes of which moisture content djusted to 65% nd weight of 100 g were put into test tube (φ3 cm 20 cm) nd sterilized t 121 o C for 90 minutes. Inoculted cotton wstes were ssembled t the pprtus (Fig. 1) nd incubted t 25 o C for 24 hours to evlute the initil growth of myceli. CO 2 concentrtions were regulted in the rtio of 0.03, 0.1, 5, nd 10% by the ir mixture (Precision scientific, USA) nd in the influx volume of 200 ml/min by the flow-meter in the 25 o C. Chrcteristics of fruitbody morphology of P. ostretus on the different ventiltion system. To exmine the morphologicl differences of P. ostretus t different ventiltion systems in the mushroom cultivtion house, the mushroom ws grown under controlled the inpouring ventiltion system (IVS) nd expouring one (EVS) djusted to temperture of 13~16 o C nd humidity of 80% or more. The ir of IVS flowed to the cultivtion house through the unit-cooler nd ones in EVS flowed out through the fn (Fig. 3). The conventionl system (CVS) depending on nturl ventiltion served s the control. Fruitdody yield nd morphologicl chrcteristics of P. ostretus in the CO 2 concentrtions. The growth chmber (100 50 50 cm) mde from cryl plte ws used to investigte the morphologicl chrcteristics on different CO 2 concentrtions (Fig. 2). In ddition, the old spwn of the precultured swdust medi were scrtched Fig. 2. CO 2 concentrtion controlling pprtus for the fruitbody development of P. ostretus. Fig. 3. The profile for the experiment by the different ventiltion system.
Chrcteristics of fruitbody morphology of P. ostretus on different wtering frequencies nd mounts. To investigte fvourble wtering frequency nd mount for the good form nd yield of P. ostretus, the wtering of 0, 1, 3 times dy nd mount 0, 0.8, 2 l, 4 l/3.3 m 2 per wtering time were done. And the yield nd morphologicl chrcteristics of P. ostretus on different wtering times flush, wtering fter 1~2 flush, nd conventionl wtering were investigted. Results nd Discussion Chrcteriztion of Fruitbody Morphology of Pleurotus ostretus 147 Mycelil growth of P. ostretus by CO 2 levels. The effects of CO 2 level on the mycelil growth of P. ostretus re shown in Tble 1. The mycelil growth of P. ostretus mesured good t 95 mm for 15 dys on the pddy strw substrtes in the CO 2 concentrtion of 0.1% nd ws moderte to be 90 mm for 15 dys on the cotton substrtes in 0.5% CO 2. On the pddy strw substrtes, the mycelil growth ws incresed to 0.1% CO 2 level nd decresed fterwrds, while the mycelil growth on the cotton wste substrtes ws incresed to 5% of CO 2 level (Tble 1). Antonio (1972) reported tht the optimum CO 2 concentrtion required for hyphl growth ws between 0.1 nd 0.5% CO 2 in Agricus bisporus. It ws suggested tht the optiml CO 2 concentrtion on the mycelil growth of P. ostretus should be higher thn one in Agricus bisporus. Yield nd morphologicl chrcteristics of P. ostretus in the CO 2 concentrtions. Cp size nd yield of fruitbodies, s indicted in Tble 2, decresed in opposition to the increse of CO 2 concentrtion. In the CO 2 concentrtion of 0.5%, the cp size ws severely decresed. Stipe Tble 1. Mycelil growth of P. ostretus on rice strw nd cotton wste substrtes in the CO 2 concentrtions CO 2 concentrtion (%) Substrte 0.03 0.1 5 10 Rice strw 88 95 73 68 Cotton wste 81 86 90 85 The length (mm) of mycelil growth in the test tube (φ3cm 20cm) for 15 dys on pprtus described in the mteril nd methods. Tble 2. Chrcteristics of fruitbody morphology nd yield of P. ostretus in the growth chmbers djusted to different CO 2 concentrtions Morphologicl chrcteristics nd yield CO 2 concentrtion (%) 0.03 0.1 0.3 0.5 Cp size 65 34 24 6 Stipe length 46 68 67 25 Yields 289 b 251 201 53 unit; mm. b unit; g per bottle. Fig. 4. Fruitbody morphology of P. ostretus in the different CO 2 concentrtions. A; 0.03%, B; 0.1%, C; 0.3%, D; 0.5%. length incresed in contrst with cp size nd yield except 0.5% level. This result grees with those of Kinugw (1994). The stipe ws elongted from 46 mm to 67 mm s long s CO 2 concentrtions ws incresed to 0.03 to 0.3%, but ws inhibited to 25 mm when CO 2 concentrtion of 0.5%. In 0.03 nd 0.1% CO 2 concentrtion, the rtio of cp dimeter to stipe length ws 1:0.7 (65 mm:46 mm) nd 1:2 (34 mm:68), respectively, to chrcterize norml types, while the rtio ws 1:4 (6 mm:25 mm) to chrcterize elongtion type of stipe in 0.3% CO 2 concentrtion. In 0.5% CO 2 concentrtion, the growth cp nd stipe were inhibited nd the shpe of stipe ws grown to jr types in bnorml (Fig. 4). The yield of P. ostretus ws high in the lowest CO 2 concentrtion of 0.03% to 289 g per 1,000 ml bottle, but ws tendency to decrese with the increse of CO 2 concentrtions (Tble 2). Morphologicl chrcteristics of P. ostretus on different tempertures nd reltive humidity. Cp size nd individul weight were 5.6 cm nd 14.9 g, respectively, t the cultivtion house controlled in the 13~16 o C nd 80% or more reltive humidity, On the other hnd, the cp size nd stipe thickness decresed with 16 o C nd 80% or more reltive humidity. Stipe thickness decresed severely with decrese of reltive humidity, nd individul weight ws the lowest t 16 o C or more nd 60% or less reltive humidity (Tble 3). Deformed fruitbodies, of which color ws ple gry nd crumbly, ppered t 16 o C or more nd 60% or less reltive humidity (Fig. 5).
148 Jng et l. Tble 3. Fruitbody morphologicl chrcteristics of P. ostretus on different cultivtion conditions Cultivtion conditions Morphologicl chrcteristics Stipe (cm) Individul weight (g) Cp (cm) Temperture o ( C) Humidity (%) Length Size excess 16 80 or more less 60 5.4 4.2 1.1 1.2 2.6 4.7 2.6 1.3 13.7 7.2 13~16 80 or more 60~80 less 60 5.3 3.9 4.1 1.3 1.2 5.6 4.6 4.9 1.9 0.6 14.9 9.3 13.4 Fig. 5. Fruitbody morphology of P. ostretus on different cultivtion conditions. It ws suggested tht the optiml temperture nd reltive humidity for typicl morphology nd productivity of P. ostretus to be suitble Koren preference were 13~ 16oC nd reltive humidity of 80% or more. Fig. 6. Fruitbody morphology of P. ostrtus on different ventiltion system. Chrcteristics of fruitbody morphology of P. ostretus on different ventiltion systems. Vrition of wind velocity nd CO2 concentrtion in the IVS ws higher thn those in the EVS, while EVS gve higher yields thn Tble 4. Fruitbody morphologicl chrcteristics nd yield of P. ostrtus on different ir ventiltion system Ventiltion system IVS α β EVS γ CVS α Wind velocity (fpm) Individul weight (g) Expnsion o b rtio ( ) body yields (g/box) CO2 concentrtion (ppm) 01 50 or more 15.3 10.7 146 164 155 250 1850 1361 0~ ~0.5 8.8 8.9 110 114 530 601 530 590 0.35 10.5 423 631 112 β γ fpm: feet per minute, IVS: Inpouring ventiltion system, EVS: Expouring ventiltion system, CVS: Conventionl ventiltion system. Expnsion rtio: the ngle of the stipe nd cp. b
Chrcteriztion of Fruitbody Morphology of Pleurotus ostretus Fig. 7. Fruitbody yields of P. ostrtus on different wtering frequencies nd mounts. other systems. In the EVS, fruitbody ppered good shpe, However, IVS cused the trumpet-like deformtion o of the cp, with expnsion rtio of 146~164, due to high CO2 concentrtion nd irregulr wind velocity (Fig. 6). Kinugw (1994) reported tht pileus expnsion ws hevily dmged by trumpet-like deformtion nd yield decresed when the fruitbodies were exposed to high CO2 149 Fig. 8. Chnges of substrte weight on different wtering frequencies nd mounts dy during the cultivtion periods. concentrtion. So, it is recommended tht the morphogenesis nd yield of P. ostrtus were influenced more by the wind velocity nd CO2 concentrtion thn ventiltion system in the cultivtion house. Chrcteristics of fruitbody morphology of P. ostretus on different wtering frequencies nd mounts. When the cultures were sprinkled t the wtering mount Tble 5. Fruitbody morphologicl chrcteristics of P. ostretus on different wtering frequencies fter flush Tretments No wtering Wtering fter 1flush Wtering fter 2flush Conventionl Cp(cm) Stipe(cm) Size Length Individul weight(g) Totl yield 2 (g/1.76 m ) 4.9 5.2 4.7 4.6 4.5 4.3 4.3 4.1 1.4 8.3 9.2 11.9 10.5 0,821 0,745 0,833 1,101 Fig. 9. Vrious deformtion of Fruitbody of P. ostretus on without wtering during the cultivtion periods.
150 Jng et l. of 0.8 l/dy, the yield ws intensive nd intend to decrese with increse wtering mounts. When the cultures were sprinkled t the wtering of once dy, yield ws the worst, But the conventionl wtering gve higher yields thn other wtering (Fig. 7). There ws no significnt difference in morphologicl chrcteristics of P. ostrtus by wtering frequency nd mount (dt not shown). This result could be considered becuse bodies were hrvested in one flush only. When the substrte weights were mesured during vegetble growing periods, there were significnt vritions. But the weights decresed during reproductive growing periods. Specilly, the weight of none-wtering substrtes decresed suddenly nd it ws observed tht their substrtes were seprted from those inside of culturing box (Fig. 8, 9). Tble 5 indicted no significnt morphologicl chrcteristics in different wtering frequencies fter flush. When chnge of substrte weight hd mesured on different wtering frequencies fter flush, conventionl wtering substrtes hd higher yields thn other nd none-wtering ones produced less yields thn others (Tble 5). But individul weight of none-wtering ws lesser thn other wtering substrtes including conventionl wtering. Stipe of some fruitbodies becme brownish by drying (Fig. 9b) nd regenertion of secondry fruitbody formtion occurred (Fig. 9c, d) in none-wtering substrtes. This result suggested tht the optimum wtering of P. ostretus should sprinkling t fruitbody before drying of substrtes regrdless of wtering frequencies nd mounts during the cultivtion periods. References Antonio, J. P. S. nd Thoms, R. L. 1972. Crbon dioxide stimultion of hyphl growth of the cultivted mushroom, Agricus bisporus (Lnge) sing. Mushroom Science 8(1): 623-629. Ch, D. Y., You, C. H. nd Kim, K. P. 1989. New technology of mushroom cultivtion. Sngrok press. pp. 1-19. Donld, J. N. 1963. Role of crbon dioxide in the control of ing of Schizophyllum commune. J. Bcteriol. 85: 1300-1308. Lmbert, E. B. 1933. Effect of excess crbon dioxide on growing mushrooms. J. of Agriculturl Reserch 47(8): 599-608. Flegg, P. B. 1978. Effect of temperture on sporophore initition nd development in Agricus bisporus. Mushroom Science 10(1): 595-602. Kinukw, K. nd Akir, S. 1994. Effect of concentrted crbon dioxide on the ing cultivted bsidiomycetes (II). Mycoscience 35: 345-352. nd Tnesk, T. 1990. Chnges in the rte of CO 2 relese from cultures of three bsidiomycetes during cultivtion. Trns. Mycol. Soc. Jpn 31: 489-500. nd Tkmtsu, Y. 1986. Effect of concentrted crbon dioxide on the ing cultivted bsidiomycetes (I). Trns. Mycol. Soc. Jpn 27: 327-340. Long, P. E. nd Jcobs, L. 1969. Some observtions on crbon dioxide nd sporophore initition in the cultivted mushroom. Mushroom Science 7: 373-384. Rudkoski, M. nd Viitmen, H. 1982. Effect of ertion nd light on body induction in Schizophylum commune, Trns. Br. Mycol. Soc. 78(1): 89-96. Ministry of Agriculture & Forestry. 2003. The ctul production of industril crop. pp. 8-9. Pul, S. nd Chilton, J. S. 1983. Chpter environmentl fctors: sustining the mushroom crop in the mushroom cultivtor. pp. 149-157. Sohi, H. S. nd Updhyy, R. C. 1989. Effect of temperture on mycelil growth of Pleurotus species nd their yield performnce on selected substrtes. Mushroom Science 12(2): 49-56. Yoo, Y. B., You, C. H. nd Ch, D. Y. 1993. Strin improvement of the genus Pleurotus by protoplst fusion. Koren. J. Mycol. 21(3): 200-211.