sdu faculty of forestry journal special edition 2009 - Orman Fakültesi

SDÜ Faculty of Forestry Journal
* Occurrence of Diplodia pinea. 0= none or few pycnidia; 1 = pycnidia detected
on < 15% of cone scales ; 2 = 15 – 50 % ; 3 = > 50%.
3.2. Detecting the inoculum availability from mature cones on the ground.
A large amount of cones colonized by D. pinea, and showing pycnidia (Table 3),
were still actively releasing conidia. Among them 55.6% of 1-yr old cones and
63.9% of >3-yrs cones were still producing inoculum. Percentage of conidia
germination after 6 h at 25°C was 47.4%.
Table 3. Inoculum availability of Diplodia pinea (pycnidia) on Pinus pinea cones.
Ages of cones
Percentage of cone scales showing D. pinea pycnidia
50
1-yr 15.6±0,8 66.7±5,6 17.8±4,0
2-yrs 0.0 42.2±5,6 57.8±4,0
>3-yrs 35.6±0,8 53.3±5,6 11.1±4,0
3.3. Sanitary conditions of harvested mature cones (3 yrs-old).
Data obtained from cones ready for seed extraction showed that damages
ranged from 28-55% according to the different forest areas considered. The most
consistent damages were caused by D. pinea (average 16%) followed by small
mammals and insects (about 6%) and L. occidentalis (4%) (Table 4). Differences
values among forests were quite pronounced particularly for the fungal parasite
(Figure 1).
Table 4. Main damages observed on 3-yrs old Pinus pinea cones.
Sampling
area Healthy
Cone conditions Causes of damage
(n.1900)
Damaged
(n.1145)
Insects*
44
L.
occid.
Small
mam.**
D.
pinea
Other
causes
MSRM-1 71.1 28.9 6.3 2.5 2.5 14.5 3.1
MSRM-2 44.8 55.2 4.5 8.0 1.3 32.0 9.4
PNM 70.9 29.1 7.5 3.2 15.6 2.4 0.4
Average±sd 62.4±15.1 37.6±15.1 6.1±1.5 4.5±3.0 6.4±7.9 16.3±14.9 4.3±4.6
*Insects: Dioryctria sp., Ernobius impressithorax, Pissodes validirostris.
** Small mammals: Dormouse (Glis glis), Squirrel (Sciurus vulgaris).
Total cones: 3045 (Migliarino 1045, Tirrenia 1000, Alberese 1000)