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Background: Multivariate analysis is a chemometric tool that has been little explored to determine physiological status under heavy metal stress. Nevertheless, PCA has an unexplored potential to determine plant physiologic status and its modification under stress factors like “heavy metals”. Objectives: Present work aims to assess the physiological and biochemical effects and responses of wheat plants under different exposition of As and Cd using multivariate models. Material and methods: Wheat plants growing in greenhouse were exposed to 0, 10 and 50 mg Kg-1 soil of As and 0, 10 and 33 50 mg Kg-1 soil of Cd until growth stage 5. After 56 days, wheat leaves and roots were collected for determination of dry weight, lipid peroxidation and the enzymatic activity of catalase, ascorbate peroxidase and guaiacol peroxidase. These measures were considerate as variables of three performed multivariate models for determination of physiological status. Results: Through interpretation of Scores plot and Loading plots in combination, it was possible to determine that both As and Cd affect chlorophyll content as well as antioxidant response. However, decreasing of chlorophyll, increase of lipid peroxidation and inhibition of antioxidant response was more accentuate in wheat plants exposed to As than those exposed to Cd. Conclusions: Multivariate analysis allows to determine the differences between the physiological behavior of both stressor which turn this chemometric tool useful for characterization of a physiological response.

In this work the effects produced by two treatments on maize crop samples have been studied. Analysis of maize grain based on two types of agronomical conditions was performed on: (a) lots treated with different fertilizers and (b) lots with different crop density. Analysis was carried out by microwave induced plasma with optical emission spectrometry (MIP OES) and included the quantification of 11 elements: Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb and Zn. With the purpose of understand the effect of agricultural practices on elemental profile, principal components analysis (PCA) and cluster analysis (CA) were used as chemometrics tools, finding a correct grouping of each crop based on the type of treatment. The obtained models can be useful to evaluate agricultural strategies, as well as for determining potential yields in maize crops.