CHAPTER-VI MITOSPORIC FUNGI I) Aero-aquatic ... CHAPTER-VI MITOSPORIC FUNGI I) Aero-aquatic Hyphomycetes Genus: Helicomyces Link Ges. Naturf. Freunde Berlin, Mag. 3: 21 (1809). The

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Text of CHAPTER-VI MITOSPORIC FUNGI I) Aero-aquatic ... CHAPTER-VI MITOSPORIC FUNGI I) Aero-aquatic...

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    CHAPTER-VI

    MITOSPORIC FUNGI

    I) Aero-aquatic Hyphomycetes

    Genus: Helicomyces Link

    Ges. Naturf. Freunde Berlin, Mag. 3: 21 (1809).

    The genus Helicomyces was introduced by Link (1809) with H. roseus Link

    as its type species. The species of the genus are charecterised by having, Colonies:

    effuse to arachnoid or tuberculate, white to pinkish, or becoming brownish in age.

    Mycelium: immersed or superficial, composed of branched, septate, hyaline to

    dilute fuscous hyphae. Conidiophores: lacking or formed as short, lateral branches

    of the repent mycelium. Conidiogenous cells: mono- or polyblastic, producing

    conidia from the apex, or synchronously and /or successively from short denticles.

    Conidia: hyaline, dry, hygroscopic, frequently uncoiling in water. Conidial

    filament: coiled 1-8 times, usually in one plane to form a disk-like body, but

    sometimes in three planes and resembling a loosely coiled spring; basal cell

    attached eccentrically; conidial secession schizolytic. The genus is represented by

    12 species (Zhao et al., 2007).

    Helicomyces colligatus R.T. Moore (Fig. 14; Plate fig. 37)

    Mycologia, 46: 89 (1954).

    Colonies: effuse, coraceous, coarsely flocculose or nearly crust-like, pale

    rose when fresh; when old composed almost entirely of conidia. Mycelium and

    conidiophores: not apparent, when young the whole stratum composed of

    semiagglutinated mycelium, conidia and conidiophores; conidia arising directly

    from the mycelium or else borne on robost conidiophores up to 45 um tall.

    Conidia: loosely coiled 1-2 times, hygroscopic, multiseptate at maturity, each cell

    containing one large vacuole or two smaller ones; filament tapering at both ends,

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    the basal end 3.5 um broad, filament enlarging to 8 um broad in the middle and

    becoming slightly less at the distal end, easily broken into segments; diameter of

    coils (32-) 50-60 um.

    Habitat: Conidia in foam sample, Yashwant Lake 16 Aug. 2009, AFN-14A; Amlibari

    dam, 29 August 2010, AFN-14B, Leg., S. N.Wagh.

    Distribution:- Karnataka: Conidia in foam samples (Ramesh, 2002), conidia in

    stem flow and through fall (Sridhar and Karamchand, 2009), on submerged wood

    (Sudheep and Sridhar, 2011).

    Remark: The present fungus is common in occurrence . The measurements of

    conidial filament, conidia and descriptions are completely agree with that of

    Helicomyces colligatus as described by Moore (1954). Therefore, it is assigned to

    that species. This makes new addition to the aquatic fungi of Maharashtra.

    Helicomyces roseus Link (Fig. 15; Plate fig. 38)

    Ges. Naturf. Freunde Berlin Mag. Neuestern Entdeck. Gesammten Naturk., 3:

    21(1809).

    Helicomyces albus Preuss, 1852 (fide Linder, 1929).

    Helicomyces elegans Morgan, 1892 (fide Linder, 1929).

    Helicomyces clarus, Morgan, 1892 (fide Linder, 1929).

    Helicomyces fuscopes Linder, Ann. Missouri Bot. Gard., 18: 15 (1931).

    Colonies: effuse, forming a thin, flocculose, white to pinkish stratum.

    Mycelium: immersed and superficial, hyaline to dilute fuscous, composed of

    branched, septate, hyphae. Stalked sclerotia (sclerotes pedicelees) often present.

    Conidiophores: short, hyaline to pale brown, mostly arising as lateral branches of

    the repent mycelium. Conidiogenous cells: mono- or polyblastic, developing as

    denticles on the repent hyphae, or as the terminal cell of the conidiophores.

    Conidia: hyaline, white to pinkish in mass, attached eccentrically, frequently with

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    hyaline secondary conidia, 25-60 m in diam. Conidial filament: (2.5) 4-5(-6) m

    in diam, multiseptate, tapering to an enlarged, obliquely flattened basal cell, coiled

    2 -3 times.

    Habitat: Conidia in foam samples, Rangawali river, 24 Aug. 2008, AFN-15A,

    Ranipur dam, 13 Sep. 2009, AFN-15B, Leg., S. N. Wagh.

    Distribution:- Karnataka: On Submerged leaves and in foam samples

    (Rajashekhar and Kaveriappa, 2003), conidia in stem flow and through fall

    (Sridhar and Karamchand, 2009), on submerged wood (Sridhar et al., 2010);

    Uttarakhand: Conidia in water samples (Arya and Sati, 2012).

    Remarks: The present fungus is frequent in occurrence . The measurements and

    descriptions of conidia are completely agree with that of Helicomyces roseus as

    described by Goos (1985). Therefore, it is assigned to that species. This makes

    new addition to the aquatic fungal flora of Maharashtra.

    Helicomyces torquatus Lane & Shearer (Fig. 16; Plate fig. 39)

    Mycotaxon. 19: 291 (1984).

    Colonies: floccose, hyaline at first, turning light brown to dark blackish-

    brwon on aging. Mycelium: mostly immersed, composed of branched, septate,

    hyphae, hyaline at first, becoming subhyaline to light brown. Conidiophores:

    micronematous, formed laterally on repent hyphae, 2-3-septate, 19.2 - 34.1- 56.4 x

    3.6 - 4.5 - 4.8 m. Conidiogenous cells: monoblastic, hyaline, elongate, 12.0 17.8

    - 24 x 3.6 4.7 - 4.8 m. Conidia produced holoblastically, terminally, and singly

    at tips of conidiogenous cells, seceding schizolytically from conidiogenous cells.

    Conidia: hyaline, multiseptate, dry, coiled 1.8 to 2.8 times, 52.8 104.4 132 m

    diam, end cells broadly spathulate, end of basal cell bearing flattened attachment

    scar. Conidia in water hydrophilic and floating or unwinding to assume a torque-

    like or sigmoid form, 372 472 528 x 4.8 6.8 7.2 m.

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    Habitat: Conidia in foam Samples, Yashwant Lake, 2 Aug. 2009, AFN-16A; Tapi

    river, 1 Aug. 2010, AFN-16B, Leg., S. N. Wagh.

    Distribution:- Karnataka: Conidia in foam samples (Ramesh, 2002).

    Remarks: The present fungus is rare in occurance. The measurement of conidia,

    conidial filament and description completely agree with that of Helicomyces

    torquatus Lane and Shearer (1984). Therefore, It is assigned to that species. This

    makes new addition to the fungi of Maharashtra.

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    II) Ingoldian Hyphomycetes

    Genus: Brachiosphaera Nawawi

    In: Descals et al., Trans. Br. Mycol. Soc., 67: 213 (1976).

    The genus Brachiosphaera was erected by Nawawi (In: Descals et al. 1976)

    with B. tropicalis Nawawi as the type species. The genus is charecterised by

    having, Mycelium: hyphae brown, septate, branched. Conidiophores: simple, rarely

    branched, macronematous or semimacronematous, erect. Conidigenous cells:

    terminal, holoblastic, proliferate sympodially or rarely precurrently. Conidia:

    sphaerical, with radiating arms, arms septate and appear simultaneously. The genus

    is represented by two species (Descals et al., 1976).

    Brachiosphaera tropicalis Nawawi (Fig. 17; Plate fig. 40)

    In: Descals et al., Trans. Br. Mycol. Soc., 67: 213 (1976).

    Mycelium: The vegetative mycelium on culture medium (2% MA) is mostly

    immersed, light brown at first, becoming dark brown to black with age. Hyphae:

    septate, thick-walled, 6-12 m wide, pigmented to varying degree with age,

    smooth to minutely tuberculate, the cells often becoming monilioid and filled with

    numerous spherical, refractive globules. Conidiophores: erect, hyaline,

    unbranched, septate. Conidiogenesis: As the conidiophore lengthens, the cell at the

    distal portion becomes slightly constricted at their septa. The end cell gradually

    becomes subglobose and finally spherical. When it reaches 30-40 m diam., 4-7

    arms (usually 4) appear simultaneously as blown out buds, and elongate rapidly,

    becoming 3-5 septate. The top arm always lies along the axis of the conidiophore

    while the rest develop from around the circumference of the sphere equidistant

    from one another. As the conidium mature, another ovoid conidiogenous cell

    develops very close to the attachment point and very soon produces another

    conidium. This process of sympodial proliferation is repeated until up to 10 or

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    more conidia are produced. Conidia: The mature conidia consist of a spherical

    body, 46-58 m diam, and filled with numerous small spherical globules up to 6

    m diam. The spherical body is yellowish brown and furnished with 4-7 radiating

    arms, 95-180 m long, 9-11 m wide at the widest point, tapering to 4-5 m wide

    at the rounded apex, constricted to 3-5 m at the point of origin and becoming 3-5

    septate. The spherical body is multinucleate and each cell of the arms contain up to

    8 nuclei.

    Habitat: Conidia in foam samples, Yashwant Lake, 30 Aug. 2009, AFN- 17A; Tapi

    river, 22 Aug. 2010, AFN-17B, Leg., S. N. Wagh.

    Distribution:- Maharashtra: Conidia in foam samples (All examined conidia, both

    in slides and illustrations from previous work of Patil and Kapadnis (1979) and

    Patil (2003 a, b) from Maharshtra, referred to as Actinospora megalospora

    correspond to B. tropicalis); Karnataka: Conidia in foam (as Actinospora

    megalospora, Sridhar and Keveriappa, 1982a), conidia in foam samples (Sridhar

    and Kaverappa, 1989b), conidia in water samples (Sridhar and Keveriappa, 1990).

    Remarks: The present fungus is rare in occurance. The measurements and

    descriptions of conidia are completely agree with that of Brachiosphaera

    tropicalis as given in Descals et al., (1976). Therefore, it is assigned to that

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