Changes in the Physiological Processes of Norway Spruce Seedlings Induced with Brown-Rot Decomposed Timber

1991

7 Abb., 6 Tab., 26 Lit. Ang.

Unselbständiges Werk

6753

200062083

The seedlings of Norway spruce Picea abies (L.) Karst. were cultivated in sand cultures with differentiated amounts of pulverized brown-rot decomposed spruce timber. Brown-rot decomposed timber induced in the seedlings changes in the basic growth parameters. If only decomposed timber was used as a substrate, the growth of seedlings was largely inhibited, and this inhibition increased during the trial. A mixture of mineral soil and decomposed timber at the rati of 1:1 permanently stimulated the seedling growth: it stimulated first of all the growth in the root part, the response of which to substrate composition was most sensitive. In the resting period, a significant shift of dry matter from the aboveground parts of seedlings to the roots occurred in variants 50 and 100. The presence of decomposed timber in the substrate was manifested as changes in the root system morphology. In decomposed timber as the only component of substrate, the growth of main root was inhibited completely and the lateral roots were short and thin. Fifty volume percent of decomposed timber used in the substrate induced the rich branching of main root; the roots of this variant were always longer than the roots of the control variant. The decomposed timber in substrate did not influence the chlorophyll content in assimilating organs. Neither did the chlorophyll a:b ratio change. Decomposed timber increased the resistance of spruce seedlings to frost; this was manifested in the higher percent survival of seedlings grown in variants 50 and 100.