Seed Testing of Maize and Wheat A Laboratory Guide - Search ...

References
Colony on seed is initially white
with white tufted mycelium tinged
Microconidia are absent.
Diagnostic characteristics for
F. equiseti macroconidia are the
CM!. 1978. Descriptions of
Pathogenic Fungi and Bacteria
No. 571 . Fusarium equiseti.
CAB, UK.
with peach but later changing to
beige and finally deep olive light
brownish yellow. Below or within
the mycelium light to bright orange
or sometimes brown spore
Macroconidia are produced from
simple or branched conodiophores.
Macroconidia are variable in size,
hyaline, sickle-shaped, distinctly
curved, with a well-developed
four to seven distinct septa, a very
long elongated and strongly
curved (whip-like) apical cell and a
well-defined foot cell.
Nath, R., Neergaard, P., and
Mathur, S.B. 1970. Identification
of Fusarium species on seeds
as they occur in blotter test.
Proc. Int. Seed Test. Assoc. 35
(1): 121-144.
McGee, D.C. 1988. Maize
Diseases: A Reference Source
for Seed Technologists. APS
Press, USA.
Zillinsky, F.J. 1983. Common
Diseases of Small Grain
Cereals: A Guide to
Identification. CIMMYT, Mexico.
masses of different size are
present, which are 'dry' in tex1ure.
In certain cases very little
mycelium is seen on the seed and
spore masses arise from the seed
surface in long, continuous rows
with ridges and furrows from
bottom to top. In other cases the
mycelium is pale white or light
orange, white, fluffy, quite
compact, covering the whole
seed, and spreading onto the
blotter, with no evidence of spore
masses when viewed with a
stereoscopic microscope.
However, in this case orange to
brown spore masses can be seen
distinct foot- shaped basal cell and
an elongated apical cell which
curves inwards. Mature conidia
have 4-7 thin but distinct septa and
measure 22-60 x 3-6 ~m .
Chlamydospores are solitary,
found at intervals along hyphae or
in chains or knots, spherical,
and 7-9 ~m diameter with thick
roughened walls.
Perithecia are rare and thinly
scattered; they are oval with a
rough outer wall, and 200-350 ~m
high x 180-240 ~m diameter.
Macroconidia are more or less
intermediate in length and width
between F. culmorum and
F. avenaceum, and differentiated
by the characteristic apical and
basal cells.
F. equiseti resembles
F. semitectum in colony
morphology and colour. However,
the shape of the macroconidia
produced in the aerial mycelium
and spore masses are distinctive.
on the seed surface by removing
Asci are club-shaped, with 4-8
some of the mycelium with a
hyaline, 2-3 septate ascospores
needle.
which narrow towards the ends
and measure 21-33 x 4-6 ~m .
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