sdu faculty of forestry journal special edition 2009 - Orman Fakültesi

SDÜ Faculty of Forestry Journal
within 10 sampling plots were investigated for the canker formations on branches
and trunks. In Aydıncık, sampling plots were consist of four circular sub-sampling
plots with a 10–m–radius, located 25 m to the north, east, south and west from the
plot centre. While in Köprülü Kanyon the length of the cankers and the height of
the cankers above ground, as well as tree features were recorded, no such
measurements were done in Aydıncık. Contrary to the survey conducted in
Köprülü Kanyon, in Aydıncık trees were also assessed for top and crown dieback,
resin exudation, foliage symptoms, and insect damage.
2.2. Fungal isolation and identification
Branch and trunk samples with cankers were collected from a number of trees
within the sampling plots and transferred to the laboratory. The samples were
surface sterilized with 70% ethanol, the outer tissues near the canker margins were
removed with a sterile scalpel, and small pieces of the affected bark transferred
onto potato dextrose agar plates (PDA; Merck, Darmstadt, Germany). Some of the
samples were incubated in moist-chamber in order to induce formation of fruiting
bodies on plant tissues. The cultures incubated at 25 ºC were identified according
to their morphological characteristics.
3. RESULTS AND DISCUSSION
During the surveys, in Köprülü Kanyon and in Aydıncık, 449 and 574 trees,
respectively, were examined (totally 1023 trees). Bark cracks and cankers, as well
as resin drops and moderate to heavy resin flows were present on the trunk,
branches and twigs at all sites. Of the 1023 trees examined, 34.4% (352) were
bearing at least one canker. Canker incidence was greater in Aydıncık than in
Köprülü Kanyon, 38.0 and 29.8%, respectively. Branch cankers were more
frequent than trunk cankers in Aydıncık (31.7% and 17.9%, respectively), while in
Köprülü Kanyon trunk cankers were significantly more common. Bark cracks
exuding resin, especially on branches and twigs, were observed often in Aydıncık,
where small perennial resin soaked cankers on declining lower branches were also
found.
While in Köprülü Kanyon the length of the cankers and the height of the
cankers above ground, as well as the tree height and diameter were recorded (Table
2), no such measurements were done in Aydıncık. In Köprülü Kanyon, among the
seedlings and saplings investigated, the average height and diameter at breast
height of 134 canker bearing individuals were 360.5 and 5.6 cm, respectively. In
this site, majority of the cankers observed were on the road–facing parts of the
saplings, mostly under breast height (mean 81.1cm). On the other hand, grazing
damage was also remarkably more prevalent in Aydıncık, especially on lower
branches where canker formations were also common. Therefore it is likely that
wounds resulting from grazing have worked as suitable entrance points for canker–
causing pathogens.
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