New Helminthosporium (Massarinaceae, Dothideomycetes) and Nigrospora (Incertae sedis, Sordariomycetes) species associated with walnut (Juglans regia L.) in ChinaAuthorZou, MengtingDepartment of Plant Pathology, Agricultural College, Guizhou University, Guiyang, 550025, ChinaAuthorAl-Otibi, Fatimah0000-0003-3629-5755Institute of Plant Health and Medicine, College of Agriculture, Guizhou University, Guiyang Guizhou 550025, ChinaAuthorHyde, Kevin David0000-0002-2191-0762Institute of Plant Health and Medicine, College of Agriculture, Guizhou University, Guiyang Guizhou 550025, China & Department of Botany and Microbiology, College of Science, King Saud University, P. O. Box 22452, Riyadh 11495, Saudi ArabiaAuthorWang, YongDepartment of Plant Pathology, Agricultural College, Guizhou University, Guiyang, 550025, ChinaAuthorPan, Xue-JunDepartment of Plant Pathology, Agricultural College, Guizhou University, Guiyang, 550025, ChinatextMycoKeys20242024-10-11109265284journal article30440810.3897/mycokeys.109.13343159c82cc4-837b-4f61-a031-9334f598c288Nigrospora yunnanensis
M. T. Zou &
Yong Wang bissp. nov.Fig. 4 a – kEtymology.
The name refers to
Yunnan
, the province where the fungus was collected.
Diagnosis.Nigrospora yunnanensis
is characterized by black, globose conidia (16.2 × 14.4 µm).
Type.China
•
Yunnan Province
:
Lincang City
;
23 ° 40 ' 26.08 " N
,
99 ° 56 ' 47.70 ″ E
;
1900 m
;
22 Dec 2023
;
on
Juglans regia
, coll.
M. T. Zou
;
HGUP 24-0007
(
holotype
); ex-type culture GUCC 24-0008 (
ITS
:
PP 915796
,
tef 1 - α
:
PP 947933
,
tub 2
:
PP 947937
)
.
Culture characteristics.
Colonies on
PDA
reaching
90 mm
diam after ten days at 25 ° C. The anterior surface and posterior surface are white, while the mycelium is thick and fluffy. Colonies on
OA
reach
90 mm
diam. after ten days at 25 ° C. The mycelium is circular, filiform, fluffy, while the surface and reverse are initially white, becoming gray to black, or black and producing a few black areas with age. Colonies on
MEA
reaching a diameter of
90 mm
after ten days at 25 ° C. The mycelium circular, filiform, thick, and fluffy. The surface and reverse are initially white, but they become gray to dark black with abundant black areas spreading from the periphery to the center as they age. Sexual morph undetermined. Asexual morph on
OA
: Hyphae 2.5–8 µm diam, smooth, hyaline to pale brown, branched, septate. Conidiophores smooth, hyaline to brown, branched, septate, sometimes reduced to conidiogenous cells. Conidiogenous cells (n = 30) 8–14 × 6–10 µm (av. = 10.4 × 8.2 µm), aggregated in clusters on hyphae, pale brown, subglobose to ampulliform. Conidia (n = 40) 14.5–18.5 × 11–17.5 µm (av. = 16.2 × 14.4 µm) solitary, globose to subglobose, black, shiny, smooth, aseptate.
Habitat.
On
Juglans regia
.
Known distribution.China
,
Yunnan Province
, Lincang city.
Additional material examined.China
•
Yunnan Province
:
Lincang
city;
23 ° 67 ' N, 99 ° 94 ' E
;
1900 m
;
22 Dec 2023
;
on
Juglans regia
; coll.
M. T. Zou
;
HGUP 24-0007
; living culture GUCC 24-0008, GUCC 24-0009, and GUCC 24-0010
.
Notes.
Three isolates from walnut leaves were obtained in this study and clustered in a well-supported clade distinguished from other known species (Fig.
4
).
Nigrospora yunnanensis
formed an independent branch. Morphological differences (Table
2
) support that they belong to different taxa.
Nigrospora yunnanensis
(GUCC 23-0008)
a
–
c
culture characteristics on media after ten days (
a
on
PDAb
on CMA
c
on
OA
)
d
–
j
conidia attached to conidiogenous cells
k
coiled hyphae. Scale bars: 10 µm (
d – k
).
Comparison of conidia and conidiogenous cells of
Nigrospora
species
related to this study.