 |
 |
SPORES single in the soil; hyaline to pale yellow (2A3); globose to subglobose; (70-)106(-150) µm diam; sometimes ovoid; 90-100 x 140-180 µm; with one subtending hypha.
SUBCELLULAR STRUCTURE OF SPORES composed of one wall with three layers (swl1-3).
 |
 |
 |
 |
 |
 |
 |
In PVLG |
||||||
Layer 1 mucilageous, hyaline, (0.3-)0.6(-0.9) µm thick, staining pinkish (8A2) in Melzer’s reagent, usually completely sloughed in mature spores.
Layer 2 laminate, smooth, hyaline, (2.5-)5.8(-11.0) µm thick.
Layer 3 laminate, smooth, hyaline to pale yellow (2A3), (2.9-)5.9(-10.0) µm thick.
SUBTENDING HYPHA hyaline to pale yellow (2A3); straight to curved; cylindrical to funnel-shaped; (11.3-)13.3(-15.7) µm wide at the spore base.
Wall of subtending hypha hyaline to pale yellow (2A3); (5.7-)6.6(-8.6) µm thick at the spore base; composed of three layers (shwl1-3), continuous with spore wall layers 1-3; layer 1 present only in very young spores.
Pore closed by a curved septum continuous with the innermost laminae of the laminate spore wall layer 3.
GERMINATION. A germ tube emerges from the lumen of the subtending hypha.
MYCORRHIZAE. In one-species cultures with the host plant Plantago lanceolata L., mycorrhizae of Gl. clarum consisted of arbuscules, vesicles, as well as intra- and extraradical hyphae staining intensively in 0.1% trypan blue.
DISTRIBUTION. In Poland, Gl. clarum has occurred in maritime dunes of Swinoujscie (53º55’N, 14º14’E; Błaszkowski 1994), the Vistula Bar (54o21’N, 19o14’E; Błaszkowski et al. 2002a), and in inland dunes of the Bledowska Desert (50o22’N, 19o34’E; Błaszkowski et al. 2002b).
Glomus clarum has also been found in cultivated and uncultivated soils of Florida, Kansas, Kentucky, West Virginia, U.S.A. (Day et al. 1987; Hetrick and Bloom 1983; Miller et al. 1985; Morton 1985; Nicolson and Schenck 1979; Schenck and Kinloch 1980; Schenck and Smith 1981), Colombia, South America (Schenck et al. 1984; Sieverding 1989), Adelaide, South Australia (McGee 1986), Singapore (Louis and Lim 1988) and in soils of maritime dunes and shores of Quebec, New Brunswick, New Scotia, Canada (Dalpé 1989), and Madras, India (Mohankumar et al. 1988).
NOTES. Glomus clarum most resembles Gl. lamellosum Dalpé et al. and Gl. luteum L.J. Kenn. et al. due to the hallo formed by the relatively thick and colourless layer adherent to the coloured structural layer of its spores (Błaszkowski et al. 2002; Dalpé et al. 1992; Kennedy et al. 1999). However, in Gl. lamellosum, this thick and colourless layer is uniform and sloughs with age, and is not a laminate and permanent as in Gl. clarum. Additionally, Gl. lamellosum and Gl. luteum still have a fourth, very thin and flexible layer that is absent in spores Gl. clarum.
REFERENCES
Błaszkowski J. 1994. Glomus clarum (Glomales, Zygomycetes), a new vesicular-arbuscular fungus to Poland. Mycotaxon 52, 99-107.
Błaszkowski J., Adamska I., Madej T. 2002. Glomus lamellosum (Glomales, Zygomycota), an arbuscular mycorrhizal fungal species new for Poland and Europe. Mycotaxon 81, 281-292.
Błaszkowski J., Adamska I., Czerniawska B. 2002a. Arbuscular mycorrhizal fungi (Glomeromycota) of the Vistula Bar. Acta Mycol. 37, 39-62.
Błaszkowski J., Tadych M., Madej T. 2002b. Arbuscular mycorrhizal fungi (Glomales, Zygomycota) of the Bledowska Desert, Poland. Acta Soc. Bot. Pol. 71, 71-85.
Dalpé Y. 1989. Inventaire et repartition de la flore endomycorhizienne de dunes et de rivages maritimes du Quebec, du Nouveau-Brunswick et de la Nouvelle-Ecosse. Naturaliste can. (Rev. Ecol. Syst.) 116, 219-236.
Dalpé Y., Koske R. E., Tews L. L. 1992. Glomus lamellosum sp. nov.: a new Glomaceae associated with beach grass. Mycotaxon 43, 289-293.
Day L. D., Sylvia D. M., Collins M. E. 1987. Interactions among vesicular-arbuscular mycorrhizae, soil, and landscape position. Soil Sci. Am. J. 51, 635-639.
Hetrick B. A. D., Bloom J. 1983. Vesicular-arbuscular mycorrhizal fungi associated with native tall grass prairie and cultivated winter wheat. Canad. J. Bot. 61, 2140-2146.
Kennedy L. J., Stutz J. C., Morton J. B. 1999. Glomus eburneum and G. luteum, two new species of arbuscular mycorrhizal fungi, with emendation of G. spurcum. Mycologia 91, 1083-1093.
Louis I., Lim G. 1988. Observations on in vitro sporulation of Glomus clarum. Trans. Brit. Mycol. Soc. 91, 698-699.
McGee P. A. 1986. Further sporocarpic species of Glomus (Endogonaceae) from South Australia. Trans. Brit. Mycol. Soc. 87, 123-129.
Miller D. D., Domoto D. P., Walker C. 1985. Mycorrhizal fungi at eighteen apple rootstock plantings in the United States. New Phytol. 100, 379-391.
Mohankumar V., Ragupathy S., Niemala C. B., Mahadevan A. 1988. Distribution of vesicular-arbuscular mycorrhizae (VAM) in the sandy beach soils of Madras coast. Current Sci. 57, 367-368.
Morton J. B. 1985. Variation in mycorrhizal and spore morphology of Glomus occultum and Glomus diaphanum as influenced by plant host and soil environment. Mycologia 77, 192-204.
Nicolson T. H., Schenck N. C. 1979. Endogonaceous mycorrhizal endophytes in Florida. Mycologia 71, 178-198.
Schenck N. C., Kinloch R. A. 1980. Incidence of mycorrhizal fungi on six field crops in monoculture on a newly cleared woodland site. Mycologia 72, 445-456.
Schenck N. C., Smith G. S. 1981. Distribution and occurrence of vesicular-arbuscular mycorrhizal fungi on Florida agricultural crops. Soil and Crop Sci. Soc. Florida, Proc. 40, 171-175.
Schenck N. C., Spain J. L, Sieverding E., Howeler R. H. 1984. Several new and unreported vesicular-arbuscular mycorrhizal fungi (Endogonaceae) from Colombia. Mycologia 76, 685-699.
Sieverding E. 1989. Ecology of VAM fungi in tropical agrosystems. Agric., Ecosyst. and Environment. 29, 369-390.
