SPORE-FORMS IN SPOROPHORES OF GANODERMA LUCIDUM (LEYSS.) KARST.

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1 SPORE-FORMS IN SPOROPHORES OF GANODERMA LUCIDUM (LEYSS.) KARST. BY SACHINDRANATH BANERJEE AND ANJALI SARKAR (Department of Botany, University o[ Calcutta) Received September 12, 1958 (Communicated by Dr. 1. Banerjee, F.A.SC.) INTRODUCTION PERHAPS it is worthwhile to place on record that although considerable work has been done on basidiospores of Ganoderma lucidum (Leyss.) Karst., informations regarding the production of secondary spores and gasterospores are very few. Buller (1933) and Bose (1935) mention that fruit-bodies of Ganoderma produce secondary spores. Bose studied Ganoderma lucidum and Ganoderma applanatum and he referred to those spores as secondary spores which are produced by the tramal hypha~ and are found in sporophores collected from Nature. Buller (1933) called them secondary basidiospores since these are asymmetrically produced at the ends of hyph~e and are shot out by drop-excretion mechanism. But none of them observed the formation of secondary spores from thin-walled hyph~e in the fruit-bodies of Ganoderma obtained in culture. That Ganoderma also produces gasterospores have been recorded by a few workers. Bose (1933), while working with Ganoderma h cidum, claimed to have seen the gasterospores not only in the pore-tubes but also in the context and trama. The existence of gasterospores in fruit-bodies of Ganoderma had also been noted by Pilat (1936). But none of them said anything about their detailed characteristics excepting in that they are round, thick-walled and verrucose. In order to throw more light on various sporeforms in G. lucidum, the present investigation was undertaken. MATERIALS AND METHODS The materials were collected from Calcutta and suburbs during the wet months of July to September The fungus appeared in the form of bracket-shaped fructifications (sometimes stipitate) on several hosts, but only those fruit-bodies which were found to grow on living trunks of Swietenia mahagoni, were collected. The fructifications usually appeared O n the trunks about one to two feet above the soil. The specimens were carefully selected 94

Spore-Forms in Sporophores of Ganoderma lucidum (Leyss.) Karst. 95 and for further study, they were brought to the laboratory, examined and studied while in a fresh condition.

2 Spore-Forms in Sporophores of Ganoderma lucidum (Leyss.) Karst. 95 and for further study, they were brought to the laboratory, examined and studied while in a fresh condition. For the study of secondary spores and gasterospores, fruit-bodies were produced in artificial culture (Banerjee and Sarkar, 1956), from secondary mycelium obtained by mating compatible primary mycelia of opposite sex. In making microscopic preparations, all sections were cut by free-hand sectioning method (Banerjee, 1935), mostly from fresh materials. For temporary mounting and staining lactophenolcotton-blue gave good results. Sections were also mounted in either warm lactophenol or lactic acid and observed without staining. Basidiospores OBSERVATIONS The basidiospores are ellipsoid or ovoid and each with a hyaline epispore projecting at the apex to form a papilla-like structure which collapses at maturity giving the spore a truncate appearance. The endospore is yellowishbrown, apparently smooth when young but becoming faintly to strongly punctate or somewhat roughened at maturity. The dimension of the basidiospores is about x 6-8 tz (Text-Fig. 1, a-b). Besides normal basidiospores, two other types of spores have also been found within the pore-tubes of the fruit-bodies of G. lucidum. The characteristic features of each type have been described as follows: (a) Secondary spores.--at maturity, these resemble the basidiospores in morphological characters so closely that in a group of spores it becomes very difficult to distinguish one from the other. Like the basidiospores, mature secondary spores are also ovoid with truncated apex, brown in colour and with hyaline epispore, but the endospore is apparently smooth or slightly punctate. The dimension of the spores also agrees closely with that of the basidiospores and it is 9-11 x6-8 tz (Text-Fig. 1, c-g). These secondary spores have been found in the sporophores, obtained either from Nature or from culture. A section through the pore-tubes of a sporophore produced in culture never shows the hymenium. Instead, the pore-tubes are lined internally with numerous thin-walled, hyaline hyphm, having dense protoplasmic contents and possessing clamp-connexions. The hyphm are either simple or profusely branched at the apices. Secondary spores, which are usually terminal, are cut off directly by these thin-walled hyphm or their branches. Formation of several spores by the branches of a single hypha in a close and aggregated manner often gives a clustered appearance (Text-Fig. 1, d).

96 SACHINDRANATH BANERJEE AND ANJALI SARKAR Sporophores collected from Nature in dry weather during the rainy season often produce secondary spores but in a different way.

3 96 SACHINDRANATH BANERJEE AND ANJALI SARKAR Sporophores collected from Nature in dry weather during the rainy season often produce secondary spores but in a different way. A section through the pore-tubes of such a sporophore shows but very few mature TExT-FIG. 1. Different spore-forms of G. lucidum: a-b, Basidiospores; c-g, Secondary spores ; h-l, Gasterospores. basidia. Instead, they are lined internally by immature basidia and numerous long tramal hyph~e are found to project into the cavities of the pores. Very often, the apices of these immature basidia become narrowed and elongated to form thin-walled living hypha~ (Text-Fig. 1, e-g). They are similar in appearance with thee tramal hyph~e. The original tramal hypha~ and also those formed by the transformation of the basidia are found to produce secondary spores terminally in the same way as they are produced

Spore-Forms in Sporophores of Ganoderma lucidum (Leysv.) Karst. 97 by the thin-walled hyaline hyph~e in the sporophores produced in artificial culture. (b) Gasterospores.

4 Spore-Forms in Sporophores of Ganoderma lucidum (Leysv.) Karst. 97 by the thin-walled hyaline hyph~e in the sporophores produced in artificial culture. (b) Gasterospores.--These spores, more accurately called 'Gasteroconidia ', have been observed in the sporophores which were collected from Nature during a long period of dry weather in the growing season. They have also been found in the hymenial regions of the sporophores of Ganoderma lucidum, produced in culture. They are always borne by the highly thickwalled, hyaline or dark-brown hyph~e within the pore-tubes, often partly filling the cavities. Terminally or from the sides of these hyph~e short, hyaline narrow, pointed, peg-like structures develop on which these spores are borne (Text-Fig. 1, h-i). Like basidiospores, gasteroconidia are also brown in colour and double-walled with verrucose endospore. But they are generally spherical or more or less subglobose in shape and provided with two usually opposite notches in the exospore. The apical notch is guarded on the two sides by two prominent projections of the endospore so that a more or less funnel-shaped depression is formed. Within the depression of the apical notch is formed a small papilla-like structure, which sometimes becomes considerably enlarged (Text-Fig. 1,j-k). The gasteroconidia are generally borne singly, but sometimes two conidia may be found situated one above the other (Text-Fig. 1,/). The width of a gasterospore varies from 6--8 t~. SUMMARY 1. In this paper information regarding the various spore-forms of Ganoderma lucidum has been presented. 2. It has been found that besides the normal basidiospores, two other spore types also occur in the fructifications of the fungus collected from Nature or produced in artificial culture. These are ' secondary spores' and ' gasterospores '. 3. Characteristic features of all the spore types have been fully described and their modes of origin noted. 4. All the three types of spores are more or less identical to each other in appearance. But the secondary spores have endospores less verrucose than the endospores of the other two types, whereas the gasterospores are characterised by two opposite notches in their exospores. REFERENCES 1. Banerjee, S.N... "Thelephorace~e of ltengal--i," lndian J. bot. Soc., 1935, 14, ,

5 98 SACHINDRANATH BANERJEE AND ANJALI SARKAR 2. Banerjee, B. N. and Sarkar, A. 3. Bose, S. R Buller, A. H. R. 6. Pilat, A. "Formation of sporophores of Ganoderma lucidum (Leyss.) Kamst. and Ganoderma applanatum (Pers.) Pat in culture," lndian J. mycol Res., 1956, 2 (1 and 2), "Abnormal spores of some Ganodermas," Mycologia, 1933, 25, "Further notes on Ganoderma lucidum," 1bid., 1935, 27 (1), 88.. Researches on Fungi, Longman's Green and Company,. Londcn, 1933, 5... Atlas des Champignos de L'Europe Polyporacte, 1936, Part I, Tome III,

Short guide to some common mycological terms

Short guide to some common mycological terms Thomas Læssøe & Jens H. Petersen Macro-morphology English (latinised English) Bulb-like (= bulbous) used for swollen stem bases, can be rimmed (= marginate).