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The determination of leaf area is fundamental for studies related to plant growth and physiology. Thus, non-destructive methods allow an accurate estimate of the leaf area through linear dimensions of the leaves. The research objective was to construct allometric equations to estimate the leaflet area of peanut cultivars. Then, 2,605 leaflets were collected from six peanut cultivars (IAC Caiapó, IAC 8112, Runner IAC 886, BRS Havana, BRS 151 L7, and IAC Tatuí), with more than 400 leaflets sampled for each cultivar. We measured the length, width, product between length and width, and leaflet area. Linear and non-linear models (linear, linear without intercept, power, and exponential) were built, and the best equation was chosen using the statistical criteria: highest coefficient of determination (R2), Pearson's linear correlation coefficient (r), Willmott's agreement index (d), lowest Akaike information criterion (AIC), and root mean square of the error (RMSE). It was found that the models that used the product between length and width were the most suitable for estimating the leaflet area of peanut cultivars. Given the little intraspecific morphological variability, it was possible to group the cultivars, and model ŷ 0.875 * LW0.929 was indicated to estimate the peanut leaflet area accurately, regardless of the cultivar. [ABSTRACT FROM AUTHOR]

This study proposes to relate the increase in phosphorus (P) supply in the soil, via phosphate fertilization, to oxidative damage and protection, phenylpropanoid metabolism, and enzymatic browning in minimally processed cassava. The roots were grown with 0, 60, and 120 kg ha–1P2O5. The roots were harvested, and the yield and P content in the root, stem, and leaves were quantified. The roots were minimally processed and stored for 12 days at 5 °C. The higher supply of P in the soil increased the P content of roots and stems but not the agro-industrial yields. Roots grown at 120 kg ha–1P2O5showed higher detection of hydrogen peroxide, which was accompanied by increased phenolic compounds, soluble quinones, and antioxidant capacity and increased activities of the enzymes superoxide dismutase, catalase, ascorbate peroxidase, polyphenol oxidase, and peroxidase. The present study thus demonstrates the role of phosphorus application, induction of the synthesis of phenolic compounds, and quality of fresh-cut cassava.