DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 9-10/1971 str. 34     <-- 34 -->        PDF

By comparing ratios of the polien grains dimensions, i. e. their indices, it is
visible that B/A and B/D indices are identical in all tree forms of Fir (Tab. 5), while
other ratios differ. Thus, the B/C index is greatest in the pollen from yellow inflorescences.,
the B/E in two-coloured, the C/D in violet, and the D/E in two-coloured
inflorescences. Through measuring the lenths of the violet, yellow and intermediate
(two-coloured) inflorescences (Tabs. 6 and 7) we came to the conclusion that
the male inflorescences with the violet pigmentation were longest, from which it
follows that the length of inflorescences was in correlation with the size of pollen.
Namely, by all appearances, the violet inflorescences produce larger pollen grains.


2. By evaluating the results of the performed investigations we came to the
conclusion that of all environmental factors influencing the germination process of
Fir pollen, greatest influence was exerted by the temperature. As regards the effect
of light on the pollen germination — despite that we had established no direct influence
of light onthe process of germination — this ought to be studied again in
detail (Tab. 10).
At a temperature of 15° C (at night) — 25° C (during the day), the Fir pollen
germinated best from the 3rd to the 6th days, the process of germination was terminated
on the 8th or 9th days (Graph 1, and Tab. 8).


Bollen from the violet and yellow inflorescences exhibited an almost identical
germinability, except that the pollen from the violet inflorescences germinated
better during the lrst, 3rd, 4th and 5th days, while from the yellow inflorescences
during the lrst, 7th, 8th and 9th days. Pollen from the intermediate inflorescences
were lagging considerably behind the first two (Tab. 8, and Graph 1).


The reaction of particular individuals to the process of germination is very
uneven. Thus, the germination percent of pollen from the Perister locality varied
from 23 to 82%, in trees from the Vrteška locality from 47 to 83%, and in trees from
Brajčino from 60 to 67%. Which means that the geographical origin of a tree exercised
an influence on the process of germination of Fir pollen.


The Fir pollen can preserve its germinability in a very simple manner for a
period of 24 months (about 750 days) if kept in an exsiccator over CaCh -f- H2SO4
(2%) in an ordinary houshold refrigerator at temperature of ca. 4° C (Graph. 2).
Pollen stored in this manner exhibited a germinability of 42% in violet inflorescences,
29% in yellow, and 36% in two-coloured ones.


When studying the formation of pollen tubes in pollens from different trees
it was noticed that they appeared 3—4 hours after sowing, and in some individuals
also after 2—3 days. In like manner it was established that pollen tubes were longer
in pollens from violet inflorescences, and shortest in pollens from wellow inflorescences
(Tabs. 11 and 12) .


A = Length of pollen grain, B = Length of pollen body, C = Width of pollen
body, D = Width of air bubble, E = Length of air bubble.