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ŠUMARSKI LIST 9-10/1964 str. 69     <-- 69 -->        PDF

Stanković D. Primena radioaktivnih izotopa u poljoprivredi i šumarstvu,
Beograd 1960.
Kramer P. J. i Kozlowski T. T., Physiology of Trees, New York, Toronto,
London 1960.
Kursanov A. L., Povezanost fizioloških procesa u biljkama. Beograd 1961.
Bura D., Mogućnost primjene nuklearne energije u izvršenju narednih zadataka
u šumarstvu, Savetovanje o primeni radio-izotopa u poljoprivredi,
veterinarstvu i šumarstvu, Beograd 1961.
Maksimov N. A., Fiziologija bilja, Novi Sad 1961.
Reuther W., Plant Analysis and Fertilizer Problems, Washington 1961.
Durman P., Primjena radioaktivnih izotopa u biljnoj proizvodnji s posebnim
osvrtom na ishranu bilja, »Agronomski glasnik« 6-7/1963. Zagreb.
10. Draganić I. i dr., Radioaktivni izotopi i zračenja I, II i III, Beograd 1963.
Testing the coalescence of roots of Narrow-leaved Ash (Fraxinus angustifolia Vahl)
by means of the radioactive istotope of phosphorus (32P)


By applying the radioactive isotopes of phosphorus (32P) the author examined
the coalescence of roots of Narrow-leaved Ash. Selected were two 12-year-old trees
which were growing at a distance of 26 cm. from one another. The radioactive isotope
of phosphorus (32P) was applied to the xylem of one the trees in a quantity of
3 mC (microcuries) in the form of KH2 32P04.

During the period of 2 to 1080 hours on the application there were taken and
measured average samples of leaves, stems and roots of treated and untreated trees.
In order to establish a possible excretion of assimilates from the root of the treated
tree into the soil, as well as the possibility of their entry into the root of the untreated
tree, there was taken and measured 48 hours after the application of 32P a
sample of the soil from the zone of the active roots of the treated tree. One tree of
Narrow-leaved Ash was also chosen from outside of the zone of the experiment and
the specific activity of its leaves was measured. The purpose of this was to avoid
errors as a consequence of the presence of radioactive dust.

The measurements were carried out by means of a scintillation counter »Well
Type« produced by the firm »Ecko«. In the computation of the data of measurement
there were taken into consideration all the necessary corrections.

On the basis of the results of research the author came to the following

1. The rate of the ascending movement of 32P in the form of KH» 32P04 is at
least 2.15 m. per hour. A more accurate rate of movement could be determined
by a frequent sampling immediately on the application of the isotope.
2. Measurements from 8 to 1080 hours after the application of ;J2P point out that
there does not exist any coalescence of the roots of Narrow-leaved Ash
because no significant results of the number of impulses in the untreated
tree were obtained.
The accumulation of 32P in the leaves and the tree of the treated Narrow-
leaved Ash was increasing — along with certain fluctuations — up to 336
or 144 hours after its application, after which up to the end of the trial it
decreased a little. The accumulation of the isotope in roots — along with
considerable fluctuations in the beginning — was increasing up to the end
of experiments.

Investigations with the radioactive isotopes should be extended to the older
trees by applying them separately to the root, and separaty to the xylem
and phloem of the stem.