Page 56 - Volume 1, Issue 2, July 2008

Travlos et al. 108
The purpose of this study was to ob-
tain a better picture of the currently exist-
ing wild oat variation, both intra- and in-
ter-specific, in wheat fields of Greece. This
information was thought as exceptionally
useful on undertaking studies for the evalu-
ation of actual control efficiency and herbi-
cide resistance problems in cereal crops of
the country. Therefore, crops in a selected
typical wheat producing region of Greece,
namely Viotia, were surveyed for two grow-
ing seasons with the main objectives to de-
termine the wild oat species competing
with the crop, their relative frequency of
occurrence and the main variations in seed-
ling morphology and growth habit.
Materials and Methods
Field survey and seed collection
The region of Viotia, which is a typical
wheat producing area in Greece, was se-
lected for the wild oat survey and the col-
lection of seeds. To facilitate recording and
for a better distribution of the sampling
sites, the region was divided into 8 distinct
subregions: (A) Thiva to Chalkida, (B) Thiva
to Mouriki, (C) Schimatari, (D) Thiva, (E) Ag-
ios Thomas, (F) Asopia, (G) Thespies-Elopia
and (H) Orchomenos (Figure 1). A number
of wheat fields, corresponding to about 1%
of the total wheat area in each subregion,
were randomly surveyed. The survey was
conducted during a two week period at the
beginning of maturity, in the first weeks of
June 2007 and the last weeks of May 2008.
Each surveyed field was walked through
by the two diagonals and records were
kept of the wild oat species present and of
their density. Furthermore, a representative
sample of panicles and seeds were collect-
ed and transferred to the laboratory.
The collected wild oat panicles and
seeds were further examined in the lab-
oratory to verify species identification;
the seeds were separated, air-dried and
stored in paper bags at room temperature
until used.
Plant growth experiments
To examine variability within the spe-
cies, the collected wild oat accessions
were grown under the same conditions, in
pot experiments conducted in the green-
house in December of 2007. Five seeds of
each accession collected during the first
year of the survey were sown in a 9-cm
pot. Each accession was sown in ten repli-
cates (pots). Following germination, seed-
lings were thinned to three per pot. In the
greenhouse, the minimum and the maxi-
mum temperature were 15 and 37° C, re-
spectively. Throughout the experiment,
the pots were watered as needed and
supplied with 50 ml/pot of modified Ho-
agland’s solution (0.25 strength) every 10
days (4).
The following characteristics were re-
corded for each accession: growth hab-
it, plant height, tillering and first pani-
cle emergence. Statistical analyses were
performed using the Statistica software
package (StatSoft Inc. 1999). Differenc-
es between means were compared using
Fisher’s least significant difference (LSD)
test at p< 0.05.
Results and Discussion
The results of the 2-year survey (Table 1) in-
Figure 1. Locations of the wheat fields surveyed in Viotia re-
gion, Greece: (A) Thiva to Chalkida, (B) Thiva to Mouriki, (C)
Schimatari, (D) Thiva, (E) Agios Thomas, (F) Asopia, (G) Thes-
pies-Elopia and (H) Orchomenos.