Mathematical Models for Leaf Area Estimates of Guava

Abstract

The aim of this work was to compare methods of determining the leaf area of guava (leaf discs and scanned images) and to model leaf area as a function of linear dimensions. Four areas of guava ‘Paluma’ were selected (12, 15, 20 and 24 months of age) for the experiment in the municipality of Pedro Canário, ES, Brazil. We randomly collected samples from 15 plants in each area. Ten leaves were chosen among the lower, middle and upper thirds of each plant to ensure that leaves of all sizes were collected, for a total of 600 leaves. Subsequently, we determined the leaf area by the methods of digital imaging and leaf discs. Linear regression analysis and correlation analysis were used to compare the methods. Linear, quadratic and power models of leaf area, as a function of the length or width and/or the product of length and width were adjusted. The methods of leaf discs and scanned images are discordant. The method of digitised images was a better fit to the width of the leaf, while the method of leaf discs was a better fit for length.

Estimation of Single Leaf Area of Acacia mangium Willd

“…Corroborating this assertion, several authors have tested and adjusted these models for other species, such as Crotalaria juncea [8], Litchi chinensis Sonn. [9], Artocarpus heterophyllus [10], Cucurbita moschata [11], Pennisetumglaucum [12] and Plectranthus barbatus Andrews [13]. Table 3 describes the nine models of equations generated for the estimation of the leaf area of Acacia mangium Willd.…”

“…Corroborating with this statement, in fact, the models involving the combination of linear measurements are notoriously reported as those that present better fit for several plant species as already observed for Crotalaria juncea [8], Litchi chinensis Sonn. [9], Artocarpusheterophyllus [10], and Plectranthus barbatus Andrews [13].…”

“…Based on the leaf dimensions of several species and without the destruction of the sample, several studies have reported the use of mathematical models to estimate leaf area [8,9,10,11,12,13,14]. With respect to A. mangium Willd., A non-destructive methodology for the determination of its leaf area is of great importance, since there are no mathematical equations in the literature that allow this measurement in the specie.…”

Modeling of the Leaf Area of <i>Maytenus obtusifolia</i> Mart. from Scanned Images

“…seek the adjustment of mathematical equations that estimates the leaf area of various crops through the linear dimensions of its leaves as reported by several authors Cucumis sativus L. [4], Vicia faba L. [5], Helianthus annuus L. [6], Crambe abyssinica [7], Jatropha curcas [8], Coffea canephora [9], Vitis vinífera L. [10], Rosa hybrida L. [11], Crotalaria juncea [12], Litchi chinensis Sonn. [13], Ormosia paraensis Ducke [2], guava [14], Artocarpus heterophyllus [15] and Plectranthus barbatus Andrews [16]. However, no work was found in the literature involving the species Maytenus obtusifolia Mart.…”

Estimation Leaf Area by Composite Leaves of Canavalia rosea Seedlings Through Linear Dimensions From Last Leaflet

“…In this way, are notorious the great number of works involving mathematical equations as non-destructive method to estimate the leaf area in a wide range of vegetal species as Cucumis sativus L. (Cho, S. Oh, M. M. Oh, & Son, 2007), Helianthus annuus L. (Rouphael, Colla, Fanasca, & Karam, 2007), Jatropha curcas (Pompelli et al, 2012), Vitis vinífera L. (Buttaro, Rouphael, Rivera, Colla, & Gonnella, 2015), Coffea canephora (Schmildt, Amaral, Santos, & Schmildt, 2015), Rosa hybrida L. (Costa, Pôças, & Cunha, 2016), Crotalaria juncea (Carvalho et al, 2017), Prunus armeniaca L. (Cirillo et al, 2017), Litchi chinensis Sonn (Oliveira, Silva, Costa, Schmildt, & Vitória, 2017), guava (Vitória et al, 2018), Carica papaya L. (Oliveira et al, 2019) and Plectranthus barbatus Andrews (Ribeiro et al, 2019).…”