Two new species of Calonectria (Hypocreales, Nectriaceae) causing Eucalyptus leaf blight in Brazil
Author
Sanchez-Gonzalez, Enrique I.
Universidade Federal de Lavras, Departamento de Fitopatologia, Lavras, MG, 37200 - 900, Brasil
Author
Soares, Thaissa de Paula Farias
Suzano Papel e Celulose S. A. Centro de Tecnologia, Aracruz, ES, 29197 - 900, Brasil
Author
Zarpelon, Talyta Galafassi
Suzano Papel e Celulose S. A. Centro de Tecnologia, Aracruz, ES, 29197 - 900, Brasil
Author
Zauza, Edival Angelo Valverde
https://orcid.org/0000-0001-8322-7689
Suzano Papel e Celulose S. A. Centro de Tecnologia, Aracruz, ES, 29197 - 900, Brasil
Author
Mafia, Reginaldo Goncalves
Suzano Papel e Celulose S. A. Centro de Tecnologia, Aracruz, ES, 29197 - 900, Brasil
Author
Ferreira, Maria Alves
Universidade Federal de Lavras, Departamento de Fitopatologia, Lavras, MG, 37200 - 900, Brasil
mariaferreira@ufla.br
text
MycoKeys
2022
2022-07-29
91
169
197
http://dx.doi.org/10.3897/mycokeys.91.84896
journal article
http://dx.doi.org/10.3897/mycokeys.91.84896
1314-4049-91-169
E86A8513E9AE5F57A7CDEC1FCF277E77
Calonectria paragominensis E.I.Sanchez, T.P.F.Soares & M.A.Ferreira
sp. nov.
Fig. 3
Etymology.
The term "
Calonectria paragominensis
" refers to the microregion of Paragominas, Brazil, which is the place where the fungus was collected.
Diagnosis.
Calonectria paragominensis
differs from the phylogenetically closely related species
C. densa
,
C. humicola
,
C. spathiphylli
and
C. pseudospathiphylli
with respect to its macroconidia dimensions.
Type
.
Brazil
,•
Para
state
,
Paragominas
microregion;
3°10'51"S
,
47°18'49"W
;
From
infected leaves of
E. grandis
x
E. brassiana
;
20 Feb. 2020
;
M.A. Ferreira
;
holotype
: UB24349,
ex-type
: CCDCA 11648 = PFC1.
GenBank
:
act
=
ON009346
;
cmdA
=
OM974325
;
his3
=
OM974334
;
rpb2
=
OM974343
;
tef1
=
OM974352
;
tub2
=
OM974361
.
Description.
Sexual morph unknown. Macroconidiophores consisted of a stipe, a suite of penicillate arrangements of fertile branches, a stipe extension, and a terminal vesicle; stipe septate, hyaline, smooth, (112-)135-207(-281)
x
(2-)2.6-3.5(-4)
μm
; stipe extension septate, straight to flexuous, (123-)147-220(-295)
μm
long, (1.5-)1.9-2.4(-3)
μm
wide at the apical septum, terminating in a globose to sphaeropedunculate vesicle, (8-)8.5-10.5(-12)
μm
diam; lateral stipe extensions (90° to the axis) also present. Conidiogenous apparatus was (40-)56-88(-113)
μm
long, (45-)67-107(-129)
μm
wide; primary branches aseptate or 1-septate, (15.7-)18.4-25.9(-30.6)
x
(3.3-)4-6(-6.5)
μm
; secondary branches aseptate, (12.7-)14.3-19.6(-22.1)
x
(3-)3.5-5(-6)
μm
; tertiary branches aseptate, (9.9-)11.6-15.3(-17.9)
x
(2.8-)3.6-5.3(-6.4)
μm
; additional branches (-4), aseptate, (10.3-)11-13.2(-14)
x
(3-)3.2-4.4(-5)
μm
; each terminal branch produced 2-4 phialides; phialides doliiform to reniform, hyaline, aseptate, (8-)9.1-11.8(-14)
x
(2-)2.7-4.1(-6)
μm
, apex with minute periclinal thickening and inconspicuous collarette. Macroconidia were cylindrical, rounded at both ends, straight, (47-)56-66(-71)
x
(4-)4.8-5.9(-7)
μm
(av. = 61
x
5
μm
), (1-3) septate, lacking a visible abscission scar, held in parallel cylindrical clusters by colorless slime. Megaconidia and microconidia were not observed.
Figure 3.
Calonectria paragominensis
A, B
macroconidiophore
C
lateral stipe extensions
D, E
conidiogenous apparatus with conidiophore branches and doliiform to reniform phialides
F, G
globose to sphaeropedunculate vesicles
H, I
one, two, and three-septate macroconidia. Scale bars: 20
μm
.
Culture characteristics.
Colonies formed abundant white aerial mycelium on MEA at 25 °C after seven days, with irregular margins and moderate sporulation. The surface had white to buff outer margins, and sienna to amber in reverse with abundant chlamydospores throughout the medium, forming microsclerotia. The optimal growth temperature was 23.8 °C, with no growth at 5 °C; after seven days, colonies at 10 °C, 15 °C, 20 °C, 25 °C, and 30 °C reached 7 mm, 23 mm, 38.3 mm, 36.1 mm, and 31.8 mm, respectively.
Substratum.
Leaves of
E. grandis
x
E. brassiana
.
Distribution.
Northeast Brazil.
Other specimens examined.
Brazil
,•
Para
state
,
Paragominas
microregion;
From
infected leaves of
E. grandis
x
E. brassiana
;
20 Feb. 2020
;
M.A. Ferreira
; cultures PFC2, PFC3, PFC4, PFC5
.
Notes.
C. paragominensis
is a new species in the
C. spathiphylli
species complex (
Liu et al., 2020
). Morphologically,
C. paragominensis
is very similar to
C. densa
, since both form lateral stipe extensions, which have not been reported for the other three species in the complex. However, the macroconidia of
C. paragominensis
(av. 61
x
5
μm
) are longer than those of
C. densa
(av. 54
x
6
μm
),
C. humicola
(av. 51
x
5
μm
) and
C. pseudospathiphylli
(av. 52
x
4
μm
) but smaller than those of
C. spathiphylli
(av. 70
x
6
μm
).