Mathematical models in determining leaf area in eggplant and scarlet eggplant seedlings


  • Leonardo Raasch Hell Federal Institute of Espírito Santo
  • Vinicius de Souza Oliveira UFES
  • Karina Tiemi Hassuda dos Santos UFES
  • Gleyce Pereira Santos UFES
  • Omar Schmildt UFES
  • Marcio Paulo Czepak UFES
  • Sara Dousseau Arantes UFES
  • Edilson Romais Schmildt



Solanum melongena, Solanum gilo Raddi, non-destructive method, linear dimensions, leaf area estimate, statistical analysis.


The objective of this study was to obtain the best mathematical equation that estimates the leaf area seedlings of eggplant (Solanum melongena) and scarlet eggplant (Solanum gilo Raddi) through the linear dimensions of the leaves. Leaves of seedlings produced in a protected environment in the horticulture sector of the Instituto Federal do Espírito Santo – Campus Itapina, Colatina, in the Northwest region of the State of Espírito Santo, Brazil, were used. At 45 days after sowing, the length (L) along the midrib and the maximum width (W) of the leaf blade were determined, the product of the multiplication between the length and width (LW) and the observed leaf area (OLA). With the measurements in hand, the first degree linear model equations were obtained, potencyand its respective coefficient of determination. it was foundby analysis of covariance the possible adequacy of only one model to meet the two species. The models were validated, through a sample of leaves intended for this purpose, where their values of L, W and LW were substituted in the modeling equations, obtaining the estimated leaf area (ELA). A simple linear equation was fitted ELA and OLA. The hypotheses H0: β0 = 0 versus Ha: β0 ≠ 0 and H0: β1 = 1 versus Ha: β1 ≠ 1 were tested by Student's t test at 5% probability. The mean absolute error (MAE) and the root mean square error (RMSE) were also determined for all equations. The power () and exponential () model equations better predicted the area of eggplant and scarlet eggplant leaves, being the most recommended for these species.

Author Biographies

Leonardo Raasch Hell, Federal Institute of Espírito Santo

Campus Itapina, Colatina, Espírito Santo, Brazil

Vinicius de Souza Oliveira, UFES

Center for Agricultural Sciences and Engineering, Alegre, Espírito Santo, Brazil

Karina Tiemi Hassuda dos Santos, UFES


Gleyce Pereira Santos, UFES


Omar Schmildt, UFES


Marcio Paulo Czepak, UFES


Sara Dousseau Arantes, UFES


Edilson Romais Schmildt

Departamento de Ciências Agrárias e Biológicas (DCAB)

Centro Universitário Norte do Espírito santo (CEUNES)

Universidade Federal do Espírito Santo (UFES)


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