NOTE ABOUT THE EFFECTS OF FERTILIZATION ON SENESCENCE NEEDLES OF PINUS-SYLVESTRIS

The positive effect of fertilization on plant growth is related to imp rovement of soil nutrient availability and plant uptake. Dry weigth of two years old needles was increased by fertilization (table III). Mea n 2 years old needles dry weight for one tree was 0.39 g for control. This was multiplied by 1.4 for Ca, 2.4 for CaMg and NPKCaMg and 3.8 fo r complete treament (including microelements). Mineral analysis of nee dles (table IV) indicated that Ca concentration was increased signific antly in all fertilized plots. Mg and K contents were increased signif icantly in treatment with Mg supply. The Mn concentration was signific antly decreased by fertilization. In Haute-Correze (France) a delay of the senescence period can have a positive effect on photosynthesis of young scots pine and consequently on growth and biomass rate. ((C) In ra/Elsevier, Paris).