AGRONOMIJAS VĒSTIS - Latvijas Lauksaimniecības universitāte

AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.10, LLU, 2008mg g -1a5,04,03,02,01,00Optimum (21/17°C) temperatureKCarotenoidschl bchl aK+Cu Cu+Cu Cd+Cu R+Cumg g -1b5,04,03,02,01,00High (27/20° C) temperatureKCarotenoidschl bchl aK+Cu Cu+Cu Cd+Cu R+CuFigure 1. The impact of copper ions and temperature on the accumulation of photosyntheticpigments in red clover leaves after the main effectK – plants irrigated by water. K+Cu – in the adaptation stage irrigated by water, in the main – 4mM CuSO 4·5H 2 O solution. Cu+Cu – in the adaptation stage irrigated by 2 mM CuSO 4·5H 2 Osolution, in the main – 4 mM CuSO 4·5H 2 O solution. Cd+Cu – in the adaptation stage irrigated by0.16 mM 3CdSO 4·8H 2 O solution, in the main – 4 mM CuSO 4·5H 2 O solution. R+Cu – in theadaptation stage irrigated by 6 ml H 2 SO 4 l -1 water, in the main 4 mM CuSO 4·5H 2 O solutionAfter the main stage, having exposed to Cd ions, the content of photosynthetic pigmentsdeclined for the plants growing at optimal temperature, except for the plants that had been exposedto acid in the adaptation stage in which the content of photosynthetic pigments increased (Fig. 2a).The content of photosynthetic pigments in the plants that grew at high temperature increased onlyfor those that had been exposed to Cu ions in the adaptation stage or for those that had not beenexposed to any contaminants at this stage (Fig 2b).mg g -1aOptimum (21/17°C) temperatureCarotenoidschl b5,0 chl a4,03,02,01,00KK+Cd Cu+Cd Cd+Cd R+Cdmg g -1b5,04,03,02,01,00KHigh (27/20° C) temperatureCarotenoidschl bchl aK+Cd Cu+Cd Cd+Cd R+CdFigure 2. The impact of cadmium ions and temperature on the accumulation of photosyntheticpigments in red clover leaves after the main exposureK – plants irrigated by water. K+Cd – in the adaptation stage irrigated by water, in the main – 0.16 mM3CdSO 4·8H 2 O solution. Cu+Cd – in the adaptation stage irrigated by 2 mM CuSO 4·5H 2 O solution, in themain – 0.16 mM 3CdSO 4·8H 2 O solution, Cd+Cd – in the adaptation stage irrigated by 0.16 mM3CdSO 4·8H 2 O solution, in the main – 0.16 mM 3CdSO 4·8H 2 O solution, R+Cd – in the adaptation stageirrigated by 6 ml H 2 SO 4 /l -1 water, in the main 0.16 mM 3CdSO 4·8H 2 O solutionHigher contents of sulphur accumulated in the stems and leaves of clover plants that grewat higher temperature, whereas nitrogen contents were similar to those identified in the plantsgrown at optimal temperature. The highest contents of sulphur accumulated when in the adaptationstage the plants had been exposed to acid, and in the main stage to acid or heavy metal ions. Theratio of nitrogen to sulphur in the vegetative parts (stems and leaves) was higher when plants grew178