SEASONAL FLUCTUATIONS OF PHOTOSYNTHESIS AND ITS PIGMENTS IN 1-YEAR MYCORRHIZED SPRUCE SEEDLINGS

Specimens of spruce Picea abies (L.) Karsten were inoculated with the fungi Laccaria laccata, Pisolithus tinctorius and Lactarius piperatus in a nursery at the time of sowing. The 1-year seedlings were then tes ted in two growth periods for their photosynthesis, chlorophyll and ca rotenoid levels, and water potential; their roots were examined with a scanning electron microscope. Increased photosynthetic activity was d etermined at the start of the growth season in only those seedlings in oculated with the fungus Laccaria laccata. The levels of chlorophyll a nd carotenoids measured in September in the needles of all three mycor rhized groups of plants were higher than in the controls.