38 S.-Afr. Tydskr. Plantk. 1982, 1(112) Short Communication

A note on Endogone and Acaulospora in South Africa

J.C. Coetzee Plant Protection Research Institute, Pretoria

Present address: Department of Biological Sciences, Peninsula Technikon, Private Bag 3, Kasselsvlei 7533 , Republic of South Africa

Accepted 11 January 1982

The identity of an endomycorrhizal previously assigned to the Endogone sensu lata is discussed. The correct name for this fungus appears to be Acaulospora laevis Gerdemann & Trappe. Endogone spp. have not yet been recorded from South Africa.

Die identiteit van 'n endomikorisa vormende swam wat vroeer aan die genus Endogone sensu lata toegeskryf is, word bespreek. Dit wil voorkom of die korrekte benaming vir hierdie swam Acaulospora laevis Gerdemann & Trappe moet wees. Endogone spp. is nag nie uit Suid-Afrika gerapporteer nie.

Keywords: Acaulospora laevis, Endogone, endomycorrhizal, . 60)Jm

Figure 1 Azygospore and attached empty vesicle (cf. Acaulospora laevis) isolated from rhizosphere soil of maize (PREM 45880). The occurence of Endogonaceous fungi in South Africa was first reported by Hattingh (1972) who described a sessile type resembling the 'honey coloured sessile' (45 flm) , thin walled (2,5 f.tm), hyaline, more or less type of Mosse & Bowen (1968) and assigned it to the cylindrical terminating in a thin walled hyaline genus Endogone sensu lata. This spore type was described vesicle of approximately the same size as the spore. This in detail (but not named) by Mosse (1970a, b, c) and was collection keys out to A. laevis with the aid of the keys also described and illustrated by Gerdemann & Nicolson by Hall & Fish (1979) and Walker & Trappe (1981). (1963) as 'spore type no. 6' (Mosse & Bowen 1968). Hattingh (1972) figured a tapering hypha, but in the Although this fungus had not been formally named by Fouriesburg collection the hypha appears to be cylindrical 1972, it was generally referred to as an Endogone sp. and abruptly attenuated. Although Mosse (1970a) (Gerdemann & Trappe 1975), and thus Hattingh's treat­ considers a strongly tapered hypha as characteristic of ment of his collection as Endogone sp. agreed with A. laevis , intraspecific variation regarding the shape of concepts accepted at the time. the hypha has been reported for Acaulospora elegans However,- Gerdemann & Trappe (1974) published a Trappe & Gerdemann and Acaulospora spinosa Walker much needed revision of the genus Endogone sensu & Trappe by Gerdemann & Trappe (1974) and Walker & Zycha, Siepmann & Linnemann (1969) and a new genus, Trappe (1981) respectively. Gerdemann & Trappe (1974) Acaulospora Gerdemann & Trappe was established to do not mention the shape of the hypha as a characteristic accommodate the sessile Endogonaceous spore types. feature of A. laevis and the present author assumes that Simultaneously they assigned Mosse & Bowen's (1968) variation may well occur in this species as well. However, 'honey coloured sessile' and 'spore type no. 6' the possibility of the Fouriesburg collection representing (Gerdemann & Nicolson 1963) to Acaulospora laevis another species should not be ignored, but more spores Gerdemann & Trappe. Hattingh's (1972) Endogone will have to be obtained to determine whether this is the spores should thus also be referred to A . laevis. case. Recently the present author found a similar spore in The specimen under discussion has been deposited in rhizosphere soil of Zea mays L. from the Fouriesburg the mycological herbarium at the PPRI, Pretoria (PREM district, eastern Orange Free State (Figure 1). This 45880). collection features a smooth, globose, honey coloured An isolate of Glomus fasciculatus (Thaxter sensu spore, 175 flm in diameter, attached to the side of a wide Gerdemann) Gerdemann & Trappe mentioned by Scho- S. Afr. J. Bot. 1982, 1(112) 39

knecht & Hattingh (1976) and a Gigaspora sp . mentioned GORTER, G .J.M.A. 1979. An annotated check list and selected by Becker & Hall (1976) seem to be the only other bibliography of South African fungi for the period 1946-1977. published records of Endogonaceous fungi from South Tech. Commun. Dep. agric. tech. Serv. (S. Afr.) 163: 1-34. Africa. On the basis of Hattingh's (1972) note, Gorter HALL, I.R. & FISH, B.G. 1979. A key to the Endogonaceae. (1979) listed Endogone as occuring in South Africa, but Trans. Br. mycol. Soc. 73:261-270. HATTINGH, M.J. 1972. A note on the fungus Endogone. Jl. S. Afr. in the light of this discussion, it is evident that species Bot. 38: 29-31. of the genus Endogone sensu Gerdemann & Trappe MOSSE, B. 1970a. Honey coloured sessile Endogone spores. I. Life (1974) have not been recorded in this country to date. history. Arch. Mikrobiol. 70: 167-175. MOSSE, B. 1970b. Honey coloured sessile Endogone spores. II. Changes in fine structure during spore development. Arch. References Mikrobiol. 74: 129-145. MOSSE, B . 1970c. Honey coloured sessile Endogone spores. III. Wall BECKER, W.N. & HALL, I.R. 1976. Gigaspora margarita , a new structure. Arch. Mikrobiol. 74: 146-159. species in the Endogonaceae. Mycotaxon 4(1): 155-160. MOSSE, B. & BOWEN, G.D. 1968. A key to the recognition of some GERDEMANN, J.W. & NICOLSON, T.H. 1963. Spores of Endogonespore types. Trans. Br. mycol. Soc. 51:469-483. mycorrhizal Endogone species extracted from soil by wet sieving and SCHOKNECHT, J.D. &HATTINGH, M.J. 1976. X-ray microanalysis decanting. Trans. Br. mycol. Soc. 46: 235-244. of elements in cells of VA mycorrhizal and non mycorrhizal onions. GERDEMANN, J.W. & TRAPPE, J.M. 1974. The Endogonaceae in Mycologia 68: 296 -303. the Pacific Northwest. Mycologia Memoir 5: 1-76. WALKER, C. & TRAPPE, J.M. 1981. Acaulospora spinosa sp . nov. GERDEMANN, J.W. & TRAPPE, J.M. 1975. Taxonomy of the with a key to the species of Acaulospora. Mycotaxon 12: 515-521. Endogonaceae. In: Endomycorrhizas, ed. Sanders, F.E. , Mosse , B. ZYCHA, H ., SIEPMANN, R. & LINNEMANN, G. 1969. Mucorales. and Tinker, P.B. , pp: 35-51. Academic Press, London. Lehre, J. Cramer.