Effect of ph in the nutrients solution and n sources on the Fe concentrations in leaves and roots and chlorophyll concentration in the youngest leaves of helianthus annuus(Kosegarten et al 1998) Treatment Chlorophyll, me/gf wt. Leaf, l g Felg dry wt. Root, Hg dry wt NHNO, PHA, control 70.8 156 NHNO,,, pH6.5 0.95* 325* NO3, pH6.0 0.28* 291** 米* *%***represent significantly from the control at p0.05, 0.01 and 0.001, respectively
Effect of pH in the nutrients solution and N sources on the Fe concentrations in leaves and roots and chlorophyll concentration in the youngest leaves of helimanthus annuus (Kosegarten et al 1998) Treatment Chlorophyll, mg/g fr.wt. Leaf, μg Fe/g dry wt. Root, μg Fe/g dry wt. NH4NO3, pH4, control 1.50 70.8 156 NH4NO3, pH6.5 0.95*** 32.5** 307* NO3 - , pH6.0 0.28*** 29.1** 351** *,**,*** represent significantly from the control at p< 0.05, 0.01 and 0.001, respectively
Translocation of iron The Feat in the cytosol is presumably oxidized in transport into the xylem Long-distance transport in the xylem is Fe3+ complex when an excess of citrate in the xylem In the phloem and in the symplasm Fe is transported as an nicotianamin
Translocation of iron • The Fe2+ in the cytosol is presumably oxidized in transport into the xylem. • Long- distance transport in the xylem is Fe3+ complex when an excess of citrate in the xylem. • In the phloem and in the symplasm Fe is transported as an nicotianamin
Fe concentration in the plant Fe concentrations in dry plant tissue are commonly around 50-100 ug/g (compared to n which is typically 10,000 50,000ugg Most of Fe is in the vegetative parts grains and tubes are often considerably low. The content of iron in the plant is effected by the soil iron availability
Fe concentration in the plant Fe concentrations in dry plant tissue are commonly around 50-100 μg/g (compared to N which is typically 10,000- 50,000 μg/g Most of Fe is in the vegetative parts, grains and tubes are often considerably low. The content of iron in the plant is effected by the soil iron availability
Roles of iron in plant 1. Fe is important in the process of chlorophyll and haem formation in plants text book p392 2. Fe is required for electron transport in photosynthesis It is an important part of several molecules that are invol ved in photosynthesis Iron sulphur proteins or ferredoxin and ferritin(tt 蛋白)
1. Fe is important in the process of chlorophyll and haem formation in plants text book p392 2. Fe is required for electron transport in photosynthesis. It is an important part of several molecules that are involved in photosynthesis. Iron sulphur proteins or ferredoxin and ferritin(铁 蛋白) Roles of iron in plant
Roles of iron in the plant 3. Chelate complex Fe is an important electron acceptor in redox reactions Haem is prosthetic groups ff 45 of several enzymes (catalase, peroxides, cytochrome oxidase etc. 4. Nitrogenase comprises an Fe protein and FeMo protein 5. Ribonucleotide reductase. It is required of synthesis of DNA and RNA, which is required for the synthesis of proteins
Roles of iron in the plant 3. Chelate complex Fe is an important electron acceptor in redox reactions Haem is prosthetic groups辅基 of several enzymes (catalase, peroxides, cytochrome oxidase etc.). 4. Nitrogenase comprises an Fe protein and FeMo protein; 5. Ribonucleotide reductase. It is required of synthesis of DNA and RNA, which is required for the synthesis of proteins