Wild oat variability in Greece
111
mal (0 tillers/plant) under the conditions
of the experiments.
Regarding the time from seedling
emergence to the emergence of the first
panicle, there seems to be a clear tenden-
cy of the
A. sterilis
accessions to reach the
flowering stages earlier than the
A. fatua
accessions (Table 3).
The intraspecific variability regarding
the two species of wild oats is quite inter-
esting. Previous reports describe
A. fat-
ua
as a highly polymorphic species ex-
hibiting wide variability (12, 16) but in our
study there was no significant phenotypic
variation among the Greek
A. fatua
acces-
sions. On the other hand, significant vari-
ation was found within
A. sterilis
when the
Greek accessions from Viotia were exam-
ined and this is in agreement with previ-
ous reports describing a wide variability
also within this species (3, 12, 16).
The results of these studies show that
wild oat variability in the wheat fields of
Viotia is significant as expected. The pres-
ence of
A. fatua
, which was questionable
so far, is now verified and part of the vari-
ability derives from the coexistence of the
two species. Most of the variability, how-
ever, derives from morphological and
physiological variations which seem to
be quite evident within
A. sterilis
and not
within
A. fatua
.
Literature Cited
Damanakis, M.E. 1982. A grass weed survey of
1.
the wheat fields in Central Greece.
Zizaniolo-
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Damanakis, M.E. 1983. Weed species in wheat
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Zizaniolo-
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Efthimiadis, P., Skorda, E., Adamidis, T. and
3.
Efthimiadou, E. 1993.
Morphological and
physiological variation in wild oat.
Proceed-
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Weeds,
Brighton (UK), 22-25 November 1993,
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Table 3.
Vegetative growth parameters of
A. sterilis
and
A. fatua
accessions from Viotia, grown in
pots for 40 days after seedling emergence.
Species
Accessions Plant height
(cm)
Tillering
No/plant
Growth habit
First panicle
emergence
A. sterilis
A6
25 b
1.3 d
Erect
No
B4
12 cd
3.3 c
Semi-erect
No
C3
19 b
1.6 d
Erect
Yes
D2
21 b
1.5 d
Erect
No
E6
5 e
5.1 a
Prostrate
No
F2
6.5 de
4.2 b
Semi-erect
No
G3
18 bc
1.4 d
Erect
Yes
H4
17 bc
2.0 cd
Erect
Yes
A. fatua
A1
36 a
0 e
Erect
No
B1
39 a
0 e
Erect
No
D1
34 a
0 e
Erect
No
H2
37 a
0 e
Erect
No
1...,49,50,51,52,53,54,55,56,57,58 60,61,62,63,64,65,66,67,68