Methodology and scientific achievements of 2003, planning for 2004 Participant 4/Rennenberg Subcontractor 2/Sandermann Freiburg meets Kranzberg forest Experiences of 2003

Field campaigns 2003 June July-August September leaves apoplastic solution xylem/phloem roots soil soil water rain water wood

Contribution of work Participant 4/RennenbergSubcontractor 2/Sandermann WP1WP2 isotopes (Kris) starch (Kris) sugar (Maria) ascorbate (Kris) glutathione (Maria) salicylic acid (Sascha) gene level (Sascha) ACC (GSF) macro arrays (2004) histochem. analyses (2004 )

Links to the other work groups Participant 4 WP1 Participant 4 WP2 Subcontractor2 WP2 Antioxidants/ injury amplification reactions Participant 8 WP2 antioxidants Participant 5 WP2 Participant 6 WP2 Fine-root functionality Participant 2 WP1 Rubisco/ PEPC-activity starch Participant1 Participant7 WP1 Transpiration gH 2 O Participant 3 Subcontractor 1

AWF extracted in the laboratory after sampling, N 2 ascorbate, redox state leaves N2N2 ascorbate, glutathione, redox state, salicylic acid, ACC, gene expression δ 13 C; Δ 18 O; δ 15 N, total C/N; starch, sugar xylem Scholander bomb, N 2 glutathione, ascorbate, redox state δ 13 C; Δ 18 O, δ 15 N, total C/N, sugar phloem exudated from bark, N 2 glutathione, ascorbate, redox state δ 13 C; Δ 18 O, δ 15 N, total C/N, starch, sugar wood collected from single twigs ascorbate, redox state δ 13 C; Δ 18 O, δ 15 N, total C/N, starch roots digged out, washed,N 2 ascorbate, redox state, gene expression δ 13 C; Δ 18 O, δ 15 N, total C/N, starch, sugar rainwater collected from a rain barrel, N 2 δ 13 C; Δ 18 O, δ 15 N, total C/N soil water will be provided by δ 13 C; Δ 18 O, δ 15 N, total C/N soil was collected in different height levels (0,5,10,15,20,25 cm), dried δ 13 C, δ 15 N, total C/N

Objectives (Kris) δ 13 C: assessment of relative activity changes between C-fixing enzymes (Rubisco/PEPC) δ 13 C is dependent from the CO 2 -concentration in the gaseous phase of the apoplast. The CO 2 -concentration is dependent from assimilation and gH 2 O. Δ 18 O: stomatal conductance WUE: assimilation/transpiration WUE intr : assimilation/gH 2 O 14 N/ 15 N: information about translocation of sugars. total C/N: C/N changes of the whole plant : seasonal/annual time scale starch: carbon fixation through carbohydrates/transport ascorbate: antioxidant status in the whole tree, direct reaction with ROS in the apoplastic solution (hear also Karin)

Few scientific achievements......

Objectives (Maria) Total sugar in: Leaves Fine roots Phloem Xylem GSH GSSG Redox status of glutathione in: Leaves Fine roots Phloem Xylem

Role of Glutathione Glutathione -tripeptide -formed in the leaves -multiple function Effects: activity and expression of genes pool and transport form of reduced S takes part in regulation/assimilation S important antioxidative substance defense against pathogens, heavy metals, etc.

SOME EFFECTS OF OXIDATIVE STRESS ON THE PHYSIOLOGY OF PLANTS: Degradation of: Proteins Amino acids Lipids Products of photosynthesis decrease Respiration increases Redox status of GSH and Ascorbate and other antioxidants change Effect on allocation

Glucose in leaves

Glutathione

Conclusions so far -Light decrease of sugar -Increase of GSSG