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 Add this item to the list   Penicillium sclerotiorum van Beyma - Fig. 41.
Page number:85 
Remarks (internal):P. multicolor Grigorieva-Manoilova & Poradielova (1915) was originally described in such vague terms that it may have represented a reduced strain of any pigmented species of Penicillium. It is therefore regarded as a doubtful species (cf. Pitt, 1980: 188). CBS 351.48, identified by Raper & Thom as P. multicolor, agrees in all details with P. sclerotiorum, except that it does not produce sclerotia. CBS 313.59, the type culture of P. adametzioides, represents a reduced strain of P. sclerotiorum; its penicilli, phialides and conidia agree completely with those of P. sclerotiorum, but its stipes are shorter, ranging from 40-120(-150) µm in length; the pigmentation, especially that of the aerial mycelium, is less pronounced than in other, more typical strains of P. sclerotiorum.
The strains examined vary slightly in conidial size and ornamentation of the conidiophore stipes.
The strains CBS 187.36, CBS 258.55 and CBS 128.65 develop large numbers of conspicuous orange-red sclerotia. Van Beyma (1937) noticed that 8-month-old cultures of his strain (CBS 187.36) had failed to produce ascospores.
P. sclerotiorum resembles P. thomii in producing long, well-developed, strictly simple conidiophores. The sclerotial cells are also similar. These species, however, differ markedly in conidial size, colony appearance and growth rate.
The hyaline to brown, finely roughened, globose conidia, which are present at least in very small numbers in all strains of P. sclerotiorum, suggest a relationship to E. euglaucum (section Pinetorum). Both species agree in growth rate; in P. sclerotiorum most conidia are ellipsoidal to pyriform, hyaline and smooth-walled, whilst E. euglaucum produces predominantly subglobose to globose, hyaline to brownish, finely roughened conidia. Moreover, the conidiophores of P. sclerotiorum are typically strictly simple, whereas those of E. euglaucum range in individual strains from simple to definitely branched and ramigenous. Therefore as long as no ascospores are found in strains with long, well-developed, strictly simple conidiophores, large phialides and predominantly ellipsoidal, hyaline conidia, it is preferable to retain the sclerotial species P. sclerotiorum to accomodate such isolates. In spite of its possible relationship with E. euglaucum, it is placed in the section Lapidosa because of the shape of its phialides and its ellipsoidal, hyaline conidia.
Description type:Non-original description 
Description:Penicillium sclerotiorum van Beyma - Fig. 41.
Penicillium implicatum Biourge var. aureomarginatum Thom - The Penicillia: 211. 1930.
Penicillium sclerotiorum van Beyma - Zentbl. Bakt. ParasitKde, Abt. 2, 96: 418. 1937.
Penicillium multicolor Grigorieva-Manoilova & Poradielova sensu Raper & Thom - Man. Penicillium: 198. 1949.
Penicillium adametzioides Abe - J. gen. appl. Microbiol., Tokyo 2: 68. 1956 (nom. inval., Art. 36); ex G. Smith - Trans. Br. mycol. Soc. 46: 335. 1963.
Sclerotia orange-red, 500- 700 µm diam, very hard, consisting of hyaline, polygonal cells with very thick walls, surrounded by sterile, encrusted hyphae in bright orange-red shades, often in clusters. Asci and ascospores not observed. Conidiophores strictly simple, only very rarely with one lower branch-like metula. Stipes (40-)100-400 x 1.5-3.0 µm, with vesicular apices up to 4-7 µm diam and walls smooth or finely roughened. Phialides in compact, usually parallel clusters of 10-16, 8-10(-12) x 2.0-2.5(-2.7) µm, with a cylindrical base and at the apex narrowed into a short, occasionally somewhat prolonged neck. Conidia in parallel chains, forming loose to somewhat ragged columns, ellipsoidal to pear-shaped, 2.2-3.2 x 1.7-2.5 µm, smooth-walled or nearly so, commonly a few of them globose, 2-3 µm diam, at first hyaline, later brown, finely roughened.
Colonies on Cz growing restrictedly, attaining 2-4 cm diam, on MEA as on Cz, but occasionally a little more rapidly, attaining 2-5 cm diam within 2 weeks at 25°C. Aerial mycelium orange to orange-red, occasionally uncoloured. Conidial areas blue-green. Reverse on Cz yellow, orange-red or reddish brown.
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