title: A multivariate approach for assessing leaf photo-assimilation performance using the IPL index.
abstract: The detection of leaf functionality is of pivotal importance for plant scientists from both theoretical and practical point of view. Leaves are the sources of dry matter and food, and they sequester CO2 as well. Under the perspective of climate change and primary resource scarcity (i.e. water, fertilizers and soil), assessing leaf photo-assimilation in a rapid but comprehensive way can be helpful for understanding plant behavior under different environmental conditions and for managing the agricultural practices properly. Several approaches have been proposed for this goal, however, some of them resulted very efficient but little reliable. On the other hand, the high reliability and exhaustive information of some models used for estimating net photosynthesis are at the expense of time and ease of measurement. The present study employs a multivariate statistical approach to assess a model aiming at estimating leaf photo-assimilation performance, using few and easy-to-measure variables. The model, parameterized for apple and pear and subjected to internal and external cross validation, involves chlorophyll fluorescence, carboxylative activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo), air and leaf temperature. Results prove that this is a fair-predictive model allowing reliable variable assessment. The dependent variable, called IPL index, was found strongly and linearly correlated to net photosynthesis. IPL and the model behind it seem to be (1) reliable, (2) easy and fast to measure and (3) usable in vivo and in the field for such cases where high amount of data is required (e.g. precision agriculture and phenotyping studies).
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CRA), Research Unit for Cropping Systems in Dry Environments, Bari, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Losciale
authors.affiliation: Department of Agricultural Science, University of Bologna, Bologna, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Manfrini
authors.affiliation: Department of Agricultural Science, University of Bologna, Bologna, Italy.
authors.forename: Brunella
authors.initials: B
authors.lastname: Morandi
authors.affiliation: Department of Agricultural Science, University of Bologna, Bologna, Italy.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Pierpaoli
authors.affiliation: Department of Agricultural Science, University of Bologna, Bologna, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Zibordi
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CRA), Research Unit for Cropping Systems in Dry Environments, Bari, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Stellacci
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CRA), Research Centre for Soil-Plant System studies, Rome, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Salvati
authors.affiliation: Department of Agricultural Science, University of Bologna, Bologna, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Corelli Grappadelli
mesh_terms: D008027:Light; D027845:Malus / Q000502:physiology*; D008962:Models, Theoretical; D015999:Multivariate Analysis; D018515:Plant Leaves / Q000502:physiology*; D031989:Pyrus / Q000502:physiology*