DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 1-2/1966 str. 168     <-- 168 -->        PDF

into lowland, mountain and subalpine ecotypes is being investigated. Initial systematic
investigations of physiological and morphological characteristics of its geographical
and site races and ecotypes have been carried out in the Institute, Ljubljana.
Established was a correlative interdependence between the growth rhytm
and the site altitude of the provenance. Noted was the early and lat phenotype, as
well as the transition types between the Oriental Beech and the European Beech
(Slovenia, Macedonia, and Serbia).


In Oaks (Quercus sp.) the situation is more complicated. Investigations are being
carried out in the SRs of Serbia, Croatia and Macedonia. In Birches were observed
Betula verrucosa and B. pubescens. their transition forms, the types distinguishing
themselves by the form of bark, as well as the types exhibiting gibbosities of cubiform
structure, as are well known in individuals occurring in northern regions (Serbia,
Macedonia). Also in Sycamore Maple (Acer pseudoplatanus) special attention
was paid to the trees with curled grain. Carried out were also morphological and
physiological investigations to determine the ecotypes (Bosnia and Hercegovina,
Slovenia).


In native Black Poplars (Populus nigra L.) varying with respect to the stem form
and resistance to Melampsora sp. was observed (Poplar Institute, Novi Sad). In
Aspen were noted forms varying in the bark colour (black, grey, green, and white),
or in the resistance to decay (Forest Institute, Skopje, and Forestry Faculty, Beograd).
In progress is a study of the population of White Willow (Salix alba L.) and
the variability of technological qualities of its wood (Poplar Institute, Novi Sad).
Described was the phenomenon of monoelinous flowers in Black Poplar and hybrid
Poplars (Forestry Faculty, Beograd; Poplar Institute, Novi Sad; Forest Institute
Skopje). Obtained was the first inbred generation of a monoecious tree of Black
Poplar (Forestry Faculty, Beograd). On these problems started to work besides the
mentioned research institutions also others (3, 26, 46, 52, 71).


At the end of this chapter we wish to point out that in this report are given
only information without mentioning detailed results and conclusions which are
presented in the published ´works. Many investigations are in progress and thus
they were only mentioned. At any rate we aimed to describe the activities and investigation
being still in the initial phase which should be extended and completed
with up-to-date methods. It would, however, be too modest not to mention that
in this short period were achieved fairly satisfactory results thanks to the efforts
and self-sacrifice of those who joined this work with interest and enthusiasm.


III. VEGETATIVE PROPAGATION
In the initial works on the improvement of forest trees in this country research
institutions were faced with the problem of vegetative propagation. In order to
establish living archives, seed plantations, tree alleys for comparison, to test the
genetic characters, etc., it was necessary to become acquainted with the methods
of grafting which suit our environmental conditions, and to study the methods of
rooting of those species which are difficult-to-root.


1. Methods of vegetative propagation
In the execution works were applied the well known methods of grafting in
greenhouses and in the open, as well as in various periods of time from April to
September. In the period 1959—1964 all research institutions were carrying out numerous
graftings. As scions were used fertile branches. The results in relation lo
the percentage of successful grafts were varied. The grafting results with coniferous
species were better than with the broadleaved ones. This was suggestive of
the necessity to find out methods for overcoming the difficulties when grafting
broadleaved species. Although the grafting in greenhouses gave very good results
with 64V» to lOO´Vo of established grafts in particular conifers, this procedure is used
less and less. The reasons for the moment are financial. Whc-n grafting conifers in
the open better results were achieved in humid (Slovenia, Croatia) than in arid regions
(Macedonia). Successful grafts in the open in Picea abies during the individual
years in the SRs of Slovenia, Croatia, and Bosnia and Hercegovina amount to
68—86!Vo, while in Macedonia only to 13—27´Vo. In Abies alba these percentages are