Jelena Pavlovic1, Jelena Samardzic2, Ljiljana Kostic1, Kristian H Laursen3, Maja Natic4, Gordana Timotijevic2, Jan K Schjoerring3, Miroslav Nikolic5. 1. Plant Nutrition Research Group, Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade, Serbia. 2. Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444-A, 11010 Belgrade, Serbia. 3. Plant and Soil Science Section, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark. 4. Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia. 5. Plant Nutrition Research Group, Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade, Serbia mnikolic@imsi.bg.ac.rs.
Abstract
BACKGROUND AND AIMS: Retranslocation of iron (Fe) from source tissues enhances plant tolerance to Fe deficiency. Previous work has shown that silicon (Si) can alleviate Fe deficiency by enhancing acquisition and root to shoot translocation of Fe. Here the role of Si in Fe mobilization in older leaves and the subsequent retranslocation of Fe to young leaves of cucumber (Cucumis sativus) plants growing under Fe-limiting conditions was investigated. METHODS: Iron ((57)Fe or naturally occurring isotopes) was measured in leaves at different positions on plants hydroponically growing with or without Si supply. In parallel, the concentration of the Fe chelator nicotianamine (NA) along with the expression of nicotianamine synthase (NAS) involved in its biosynthesis and the expression of yellow stripe-like (YSL) transcripts mediating Fe-NA transport were also determined. KEY RESULTS: In plants not receiving Si, approximately half of the total Fe content remained in the oldest leaf. In contrast, Si-treated plants showed an almost even Fe distribution among leaves with four different developmental stages, thus providing evidence of enhanced Fe remobilization from source leaves. This Si-stimulated Fe export was paralleled by an increased NA accumulation and expression of the YSL1 transporter for phloem loading/unloading of the Fe-NA complex. CONCLUSIONS: The results suggest that Si enhances remobilization of Fe from older to younger leaves by a more efficient NA-mediated Fe transport via the phloem. In addition, from this and previous work, a model is proposed of how Si acts to improve Fe homeostasis under Fe deficiency in cucumber.
BACKGROUND AND AIMS: Retranslocation of iron (Fe) from source tissues enhances plant tolerance to Fe deficiency. Previous work has shown that silicon (Si) can alleviate Fe deficiency by enhancing acquisition and root to shoot translocation of Fe. Here the role of Si in Fe mobilization in older leaves and the subsequent retranslocation of Fe to young leaves of cucumber (Cucumis sativus) plants growing under Fe-limiting conditions was investigated. METHODS:Iron ((57)Fe or naturally occurring isotopes) was measured in leaves at different positions on plants hydroponically growing with or without Si supply. In parallel, the concentration of the Fe chelator nicotianamine (NA) along with the expression of nicotianamine synthase (NAS) involved in its biosynthesis and the expression of yellow stripe-like (YSL) transcripts mediating Fe-NA transport were also determined. KEY RESULTS: In plants not receiving Si, approximately half of the total Fe content remained in the oldest leaf. In contrast, Si-treated plants showed an almost even Fe distribution among leaves with four different developmental stages, thus providing evidence of enhanced Fe remobilization from source leaves. This Si-stimulated Fe export was paralleled by an increased NA accumulation and expression of the YSL1 transporter for phloem loading/unloading of the Fe-NA complex. CONCLUSIONS: The results suggest that Si enhances remobilization of Fe from older to younger leaves by a more efficient NA-mediated Fe transport via the phloem. In addition, from this and previous work, a model is proposed of how Si acts to improve Fe homeostasis under Fe deficiency in cucumber.
Authors: Heng-Hsuan Chu; Jeff Chiecko; Tracy Punshon; Antonio Lanzirotti; Brett Lahner; David E Salt; Elsbeth L Walker Journal: Plant Physiol Date: 2010-07-12 Impact factor: 8.340
Authors: Jelena Pavlovic; Jelena Samardzic; Vuk Maksimović; Gordana Timotijevic; Nenad Stevic; Kristian H Laursen; Thomas H Hansen; Søren Husted; Jan K Schjoerring; Yongchao Liang; Miroslav Nikolic Journal: New Phytol Date: 2013-03-18 Impact factor: 10.151
Authors: Brian M Waters; Carlos Lucena; Francisco J Romera; Gena G Jester; April N Wynn; Carmen L Rojas; Esteban Alcántara; Rafael Pérez-Vicente Journal: Plant Physiol Biochem Date: 2007-03-14 Impact factor: 4.270
Authors: José María Lozano-González; Clara Valverde; Carlos David Hernández; Alexandra Martin-Esquinas; Lourdes Hernández-Apaolaza Journal: Plants (Basel) Date: 2021-11-27
Authors: Jelena Pavlovic; Ljiljana Kostic; Predrag Bosnic; Ernest A Kirkby; Miroslav Nikolic Journal: Front Plant Sci Date: 2021-06-23 Impact factor: 5.753