sdu faculty of forestry journal special edition 2009 - Orman Fakültesi

2. MATERIAL AND METHODS
SDÜ Faculty of Forestry Journal
Norway spruce cones were collected in a seed orchard (Stand 1) in southern
Finland, and in a naturally regenerated stand (Stand 2) in northern Finland. A
random sample of previous year’s (2006) and current-year (2007) cones, were
collected in Stand 1 in 5 times in 2007. Similar sampling was performed in Stand 2
for the current-year cones in 5 times in 2007 and for the previous year’s cones in 8
intervals in 2006-2007. The cones were cut from sample trees either using branch
scissors (Stand 1) or a lifting cage (Stand 2).
Overwintered and current-year leaves of Prunus padus, Pyrola sp. and Orthilia
secunda were collected along the cone sampling in May-October 2007 in Stand 1,
and 7-19 times in 2007-8 in Stand 2. In a third group of seed orchards (Stand 3) in
southern Finland, leaves of P. padus and Pyrola sp. were collected in 8 times in
2007. Overwintered P. padus leaves were collected in March-May and current-year
leaves were collected between early May and early October.
The occurrence, incidence and distribution of rust fruitbodies (spermogonia,
aecia), and proportion of sporulating fruitbodies were recorded in cones under
stereo microscope. Leaves of alternate hosts were investigated for the occurrence,
incidence and stage of sporulation of rust uredinia, telia and basidia per leaf. Rust
fruiting stages were also selected and further studied using a JEOL JSM 6300F
field emission scanning electron microscope (FESEM).
3. RESULTS
3.1. Rust incidence and sporulation in current-year cones
In Stand 1, cones collected in late May to mid-June bore no rust fruitbodies. In
late June, about 2 % of the sample cones carried C. pirolata spermogonia and 5 %
carried immature T. areolata aecia. None of the aecia were sporulating. The T.
areolata aecia located on both sides of cone scales along the entire cone. No fungal
structures resembling T. areolata spermogonia were observed. In the early August,
7 % of the sample cones bore C. pirolata aecia that located on outer (abaxial) side
of scales, being currently sporulating or already had finished sporulating and
ruptured. Two percent of the sample cones carried T. areolata aecia that occurred
in all the scales of cones. None of the T. areolata aecia sporulated yet. In the early
October, 2 % of the cones carried both T. areolata and C. pirolata aecia in cone
scales. Chrysomyxa pirolata aecia were ruptured with only individual aeciospores
within aecia. Thekopsora areolata aecia were immature and non-sporulating.
3.2. Rust incidence and sporulation in previous years’ cones
3.2.1. Stand 1
Only T. areolata aecia were observed in previous year’s cones. In late May, 35
% of the sample cones bore T. areolata aecia with 92 % of the cone scales being
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