Estimation of leaf area of Erythroxylum citrifolium from linear leaf dimensions

João Everthon Da Silva Ribeiro,Francisco Romário Andrade Figueiredo,Manoel Bandeira De Albuquerque,Ester Dos Santos Coêlho,Sérgio De Faria Lopes

doi:10.14393/bj-v35n6a2019-41743

João Everthon Da Silva Ribeiro, Francisco Romário Andrade Figueiredo + Show 3 more

Open Access

https://doi.org/10.14393/bj-v35n6a2019-41743

Copy DOI

Abstract

Erythroxylum citrifolium is a neotropical plant species recorded in all regions of Brazil. Determining leaf area is of fundamental importance to studies related to plant propagation and growth. The objective was to obtain an equation to estimate the leaf area of E. citrifolium from linear dimensions of the leaf blade (length and width). A total of 200 leaf blades were collected in Parque Estadual Mata do Pau-Ferro in the municipality of Areia, state of Paraíba, Northeast Brazil. The models evaluated were: linear, linear without intercept, quadratic, cubic, power and exponential. The best model was determined by the criteria of: high coefficient of determination (R²), low root mean square error (RMSE), low Akaike information criterion (AIC), high Willmott concordance index (d) and a BIAS index close to zero. All of the models constructed satisfactorily estimated the leaf area of E. citrifolium, with coefficients of determination above 0.9050, but the power model using the product between length and width (L*W) ŷ = 0.5966 * LW1.0181 was the best, with the highest values of R² and d, low values of RMSE and AIC, and a BIAS index closest to zero.

Highlights

Erythroxylum citrifolium A.St.-Hil. (Erythroxylaceae), commonly known as cumixá, is a Neotropical plant species distributed throughout Central and South America from Mexico to Southern Brazil, with records in all regions of Brazil (PLOWMAN; HENSOLD, 2004; LOIOLA et al, 2007)
The leaf blades of E. citrifolium varied in length (L) from 1.20 to 17.91, with a mean of 8.60 cm, and width (W) from 0.43 to 6.13 cm, with a mean of 2.82 cm
Variation in the linear dimensions of E. citrifolium leaf blades showed that length and width had the low values for the coefficient of variation, while greater variability was observed for their product (L*W) and leaf area (Table 1)

Summary

INTRODUCTION

Erythroxylum citrifolium A.St.-Hil. (Erythroxylaceae), commonly known as cumixá, is a Neotropical plant species distributed throughout Central and South America from Mexico to Southern Brazil, with records in all regions of Brazil (PLOWMAN; HENSOLD, 2004; LOIOLA et al, 2007). (Erythroxylaceae), commonly known as cumixá, is a Neotropical plant species distributed throughout Central and South America from Mexico to Southern Brazil, with records in all regions of Brazil (PLOWMAN; HENSOLD, 2004; LOIOLA et al, 2007) It is found in the most varied types of vegetation, but mainly in remnants of humid forests of the Atlantic Forest biome and in mountain forests known as Brejos de Altitude (LOIOLA; COSTALIMA, 2015). Non-destructive methods allow for numerous evaluations of the same plant with speed and precision, and without destroying the sample (MOTA et al, 2014) One such indirect method is estimating leaf area by means of regression equations using actual leaf area as a function of leaf parameters (length and width), which are directly related to leaf surface (ZHANG; PAN, 2011). The objective was to obtain an equation for estimating the leaf area of Erythroxylum citrifolium from linear dimensional parameters of leaf blades

MATERIAL AND METHODS

RESULTS AND DISCUSSION

CONCLUSIONS