title: Impact of anatomical traits of maize (Zea mays L.) leaf as affected by nitrogen supply and leaf age on bundle sheath conductance.
abstract: The mechanism of photosynthesis in C4crops depends on the archetypal Kranz-anatomy. To examine how the leaf anatomy, as altered by nitrogen supply and leaf age, affects the bundle sheath conductance (gbs), maize (Zea mays L.) plants were grown under three contrasting nitrogen levels. Combined gas exchange and chlorophyll fluorescence measurements were done on fully grown leaves at two leaf ages. The measured data were analysed using a biochemical model of C4photosynthesis to estimate gbs. The leaf microstructure and ultrastructure were quantified using images obtained from micro-computed tomography and microscopy. There was a strong positive correlation between gbsand leaf nitrogen content (LNC) while old leaves had lower gbsthan young leaves. Leaf thickness, bundle sheath cell wall thickness and surface area of bundle sheath cells per unit leaf area (Sb) correlated well with gbsalthough they were not significantly affected by LNC. As a result, the increase of gbswith LNC was little explained by the alteration of leaf anatomy. In contrast, the combined effect of LNC and leaf age on Sbwas responsible for differences in gbsbetween young leaves and old leaves. Future investigations should consider changes at the level of plasmodesmata and membranes along the CO2leakage pathway to unravel LNC and age effects further.
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium; Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands.
authors.forename: Moges
authors.initials: M
authors.lastname: Retta
authors.affiliation: Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands; BioSolar Cells, P.O. Box 98, 6700 AB Wageningen, The Netherlands.
authors.forename: Xinyou
authors.initials: X
authors.lastname: Yin
authors.affiliation: Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands; BioSolar Cells, P.O. Box 98, 6700 AB Wageningen, The Netherlands.
authors.forename: Peter E L
authors.initials: PE
authors.lastname: van der Putten
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium.
authors.forename: Denis
authors.initials: D
authors.lastname: Cantre
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium; Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands; BioSolar Cells, P.O. Box 98, 6700 AB Wageningen, The Netherlands.
authors.forename: Herman N C
authors.initials: HN
authors.lastname: Berghuijs
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium.
authors.forename: Quang Tri
authors.initials: QT
authors.lastname: Ho
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Verboven
authors.affiliation: Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands; BioSolar Cells, P.O. Box 98, 6700 AB Wageningen, The Netherlands.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Struik
authors.affiliation: BIOSYST-MeBioS, KU Leuven/Flanders Center of Postharvest Technology, Willem de Croylaan 42, B-3001 Leuven, Belgium. Electronic address: bart.nicolai@kuleuven.be.
authors.forename: Bart M
authors.initials: BM
authors.lastname: Nicolaï
mesh_terms: D002734:Chlorophyll / Q000378:metabolism; D008854:Microscopy, Electron; D009584:Nitrogen / Q000494:pharmacology*; D010788:Photosynthesis; D018515:Plant Leaves / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology; D013997:Time Factors; D003313:Zea mays / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*
chemical_list: D002734:Chlorophyll; D009584:Nitrogen
keywords: C(4) photosynthesis; Diffusive resistance; Image analysis; Microstructure; Nitrogen content