Effect of season and soil treatments on carbohydrate concentrations in Norway spruce (Picea abies) mycorrhizae.

We studied effects of season and soil treatments (watering, acidification, liming and combinations of these treatments) on soluble carbohydrates of mycorrhizal roots of Norway spruce (Picea abies (L.) Karst.). Arabinose, arabitol, fructose, glucose, inositol, lactose, mannitol, pinite, quinate, raffinose, shikimate, stachyose and trehalose were identified by HPLC. Concentrations of inositol, lactose and pinite were constant throughout the year, whereas concentrations of raffinose, stachyose and trehalose were higher in winter than in summer, and concentrations of glucose, fructose and mannitol increased from February to September. Soil acidification and liming had no effect on the annual mean concentrations of fructose, glucose, lactose, pinite, raffinose and stachyose. Liming increased quinate concentrations and decreased arabitol concentrations. Annual mean concentrations of arabinose and mannitol decreased in response to soil acidification. Annual mean concentrations of inositol increased in response to irrigation. None of the soil treatments affected the mean annual concentration of trehalose.