Effect of ammonium and nitrate source of nitrogen on productivity of photosynthesis in Scots pine (Pinus silvestris L.) seedlings

Water culture and sand culture seedlings of Scots pine were investigated in respect to their reaction to ammonium or nitrate source of nitrogen nutrition. Photosynthesis, respiration, and dry matter production were studied in three and four months old plants. The results are preliminary but they have indicated that the effect of various form of nitrogen nutrition on gas exchange and growth rates could change during the growing season

Effect of ammonium and nitrate source of nitrogen on productivity of photosynthesis in Scots pine (Pinus silvestris L.) seedlings

Water culture and sand culture seedlings of Scots pine were investigated in respect to their reaction to ammonium or nitrate source of nitrogen nutrition. Photosynthesis, respiration, and dry matter production were studied in three and four months old plants. The results are preliminary but they have indicated that the effect of various form of nitrogen nutrition on gas exchange and growth rates could change during the growing season

Relationship between dry matter production and carbon dioxide absorption in seedlings of Scots pine (Pinus silvestris L.) in their second vegetation season

Accumulation of dry matter in needles, lignified stems and roots during the second vegetation season was compared with seasonal changes in photosynthesis and respiration activities of the se organs. Whereas growth analysis concerned plants growing at nearly natural course of external conditions, gas exchange determinations were made at constant laboratory conditions. For comparison of dry matter production and photosynthetic ability of a plant new terms „assimilation capacity" and „efficiency of assimilation" were introduced as possible expressions of photosynthetic productivity. Two ecotypes of Scots pine originating from lowland and highland regions of the country exhibited slightly different pattern of the investigated characteristics