Page 55 - Volume 1, Issue 2, July 2008
Basic HTML Version
Hellenic Plant Protection Journal
1:
107-112, 2008
Wild oat variability in wheat fields of Viotia in Central Greece
I.S. Travlos
1
, C.N. Giannopolitis
2
and E.A. Paspatis
1
Summary
Wild oat variability in wheat fields of Greece was examined by conducting a two-
year field survey in Viotia, a typical wheat producing region in the central part of the country, and
greenhouse experiments to compare seedlings grown from wild oat accessions of this region un-
der the same conditions.
The field survey indicated that, despite the widely adopted practice of using herbicides, wild oats
were found at the time of maturation to be present in most of the wheat fields (83-91%). The spe-
cies present in all cases was
Avena sterilis
while
A. fatua
was found to coexist in small patches and
at lower densities only in 11-15% of the surveyed fields. For the safe
in situ
recognition of the spe-
cies, a set of selected characters based on the mature spikelets is proposed.
In the greenhouse experiments great variability was observed with regards to growth habit and
tillering in seedlings of the
A. sterilis
but not of the
A. fatua
accessions. Seedlings of the
A. sterilis
accessions exhibited an erect, a semi-erect or a prostrate growth habit, the latter being associat-
ed with a larger number of tillers per plant.
Additional keywords
:
Avena sterilis
,
Avena fatua
, biotypes, ecotypes, growth pattern, phenotypic
variation, weeds
on the species present and secondly on
morphological and physiological variation
within each species. There are reports in
the literature describing
A. fatua
as a high-
ly polymorphic species exhibiting wide
variability (11, 12). In the case of
A. sterilis
,
there have also been reports of wide varia-
bility for several traits, including number of
spikelets per panicle and seed traits (8, 12).
In Greece, much of the area under cere-
als is invariably infested with wild oats. The
main species is said to be
A. sterilis
while
A.
fatua
is thought to be of minor importance
and confined to the north of the country
(13). In a survey conducted by Damana-
kis in 1982 in the wheat fields of Central
Greece, there was no presence of
A. fatua
recorded while
A. sterilis
was so abundant
to rank as the most widespread and trou-
blesome weed in cereals of the area (1).
Morphological and physiological variation
within
A. sterilis
in Greece has already been
documented by Efthimiadis
et al
(3).
Introduction
Of the various
Avena
species (wild oats)
known to occur in Europe (15), two are
commonly found in crops and are regard-
ed as important weeds,
Avena fatua
L. and
Avena sterilis
L. (5, 10, 14). These two spe-
cies are particularly competitive in cereal
crops, A.
fatua
being widespread in North
West Europe or the cooler regions of Eu-
rope and
A. sterilis
usually found in warm-
er regions of Southern Europe and the
Mediterranean basin (9, 13).
Wild oat variability in a region is an im-
portant parameter which must be consid-
ered in evaluating efficacy of control strat-
egies. This variability is firstly dependent
Laboratory of Integrated Weed Management & Plant
Growth Regulators (1) and Laboratory of Chemical
Weed Management (2), Department of Weed Science,
Benaki Phytopathological Institute, 8 St. Delta str., GR-
145 61 Kifissia (Athens), Greece
Corresponding author:
