Content uploaded by Olinto Liparini Pereira
Author content
All content in this area was uploaded by Olinto Liparini Pereira
Content may be subject to copyright.
Black mildew disease on the neotropical tree Cecropia glaziovi
in Brazil, caused by Appendiculella echinus
O. L. Pereira
A,B
and M. Silva
A
A
Departamento de Fitopatologia, Universidade Federal de Vi¸cosa, 36570-000, Vi¸cosa, MG, Brazil.
B
Corresponding author. Email: oliparini@ufv.br
Abstract. Appendiculella echinus belongs to the order Meliolales. The fungi of this group are known as black mildews.
A. echinus was observed on leaves of Cecropia graziovi in the ‘Reserva Florestal da Mata do Paraíso’ in the state of Minas
Gerais, Brazil. This is the first record of A. echinus on C. graziovi and the second host record for this fungus in Brazil,
previously known only from Coussapoa sp.
Introduction
Cecropia graziovi Snethl. (known in Brazil as ‘embaúba’)isa
pioneer forest species belonging to the Cecropiaceae, which
occurs in the Brazilian Atlantic Rain Forest, especially in the
forest borders and secondary forests. Its fruits, twigs and
leaves are important food sources for Bradypus species in the
neotropics and are also used in Brazilian folk medicine for
multiple purposes.
Materials and methods
In May 2008, plants of C. glaziovi (Fig. 1) were found colonised
by a species of Meliolales (black mildew) in the ‘Reserva
Florestal da Mata do Paraíso’,Vi¸cosa city, state of Minas
Gerais, Brazil. Samples of infected leaves were collected,
photographed and dried in a plant press. Observations and
measurements were carried out by means of a Carl Zeiss
Standard W and photographs by means of an Olympus BX 51
light microscope fitted with a digital camera (Evolt E330).
Wherever possible, 30 measurements were made of the
structures mounted.
Taxonomic description
Appendiculella echinus (P. Henn.) Hoehn. (Figs 2–4)
A description of the fungus on host tissue follows. Colonies
on the adaxial surface of leaves, mostly epiphyllous, black,
velvety, scattered, numerous, up to 3 mm in diameter. Internal
mycelium not observed. Dark brown hyphae, septate, straight
to undulate, branching opposite at an acute to wide angle,
mycelial cells 12.5–37.5 7.5–12.5 mm, closely reticulate,
producing appressoria and few phialides. Appressoria alternate
to unilateral, brown, straight to curved; stalk cells cuneate to
cylindrical, 5.0–15.0 6.0–11.0 mm. Head cells ovate or
elliptical, lobate or angulose, 14.0–24.0 12.5–22.5 mm.
Conidiogenous cells few, mixed with appressoria, alternate
to opposite, ampulliform, brown, 20.0–22.5 10.0–12.5 mm.
Larviform
appendages, numerous, light brown, transversely
striate, grouped around the perithecia apex, curved,
27.5–65.0 7.5–22.5 mm. Perithecia black, scattered, globose,
verrucose, 92.5–200 mm diameter, surface cells conoid, with
numerous larviform appendages. Asci evanescent, 2
ascospores per ascus. Ascospores elliptic, rounded at the tips,
Fig. 1. Cecropia graziovi trees in the ‘Reserva Florestal da Mata do Paraíso’,
Vi¸cosa, State of Minas Gerais, Brazil.
CSIRO PUBLISHING
www.publish.csiro.au/journals/apdn Australasian Plant Disease Notes, 2009, 4,4–5
Australasian Plant Pathology Society 2009 10.1071/DN09002 1833-928X/09/010004
40.0–50.0 16.0–17.5 mm, smooth, 4-septate, constricted at the
septa, dark brown.
Material examined: Brazil. Reserva Florestal da Mata do
Paraíso, Vi¸cosa, State of Minas Gerais, on leaves of Cecropia
graziovi, 19 May 2008, O.L. Pereira VIC 30701.
The black mildew fungus found on C. graziovi belongs to the
genus Appendiculella. This genus has perithecia with larviform
appendages and differs from Irenopsis by the presence of
perithecial setae on the latter. Meliola have setae on external
mycelia and Asteridiella differs from all others by its glabrous
perithecia and mycelia (Hansford 1961). Only two species
belonging to Meliolales are known to occur on Cecropia
spp. (Hansford 1961) viz. Appendiculella echinus (P. Henn.)
Hoehn. has been reported on Cecropia sp. in British Guiana,
A. echinus var. dominguensis Hansf. has been reported on
Cecropia peltata L. in Dominican Republic and A. tonkinensis
(K. & R.) Toro var. cecropiae (Stev.) Hansf. has been reported
on two other Cecropia spp. in Panama. The microscopic
observations of C. graziovi matched with the description of
A. echinus, a species previously reported in Brazil, but only on
Coussapoa sp. (Hansford 1961). This is therefore the first report
of A. echinus on leaves of C. graziovi.
Acknowledgements
This work is part of an ongoing program of surveying and describing the
foliicolous and phytopathogenic mycodiversity of ‘Reserva Florestal da Mata
do Paraíso’,Vi¸cosa, Minas Gerais, Brazil.
Reference
Hansford CG (1961) The Meliolineae – A monograph. Beihefte Sydowia 2,
1–806.
Manuscript received 14 October 2008, accepted 16 January 2009
(a)(b)
Fig. 4. Appendiculella echinus ex Cecropia graziovi.(a) Perithecium with
ascospores cylindrical, 4-septate. (b) Perithecium with immature asci (ia).
Bars = 50 mm(a); 25 mm(b).
(a)(b)
Fig. 3. Perithecia of Appendiculella echinus ex Cecropia graziovi.
(a) Immature. (b) Mature with larviform appendages. Bar = 50 mm.
Fig. 2. Appendiculella echinus ex Cecropia graziovi. Hyphae with opposite
conidiogenous cells (cc). Alternate appressoria (ap). Bar = 20 mm.
Black mildew of Cecropia Australasian Plant Disease Notes 5
http://www.publish.csiro.au/journals/apdn
