Estimating the Leaf Area of Irvingia Gabonensis (Aubry-Lecomte Ex O’ Rorke) Baill from Linear Measurement

摘要

Leaf area measurements are of great value in physiological and agronomic studies. Leaf area is important for plant light interception, growth analysis, photosynthesis, leaf area index estimation among others. This study focused on estimating the leaf of Irvingia gabonensis using a linear (non-destructive) measurement. A total of 90 leaves were selected randomly from nursery and field which represented different leaf sizes ranging from small (3 cm width), medium (5 cm width) and large (7 cm width). The lamina length (L) and lamina width (W) were measured with a ruler, while the leaf area (LA) were measured using a software model WinRHizo PRO2005, installed on computer system with an attached scanning machine. The best fit model was selected based on F test and coefficient of determination R 2 . Correlation of all parameters is significant at 1% level. Product of square length and width [(LW) 2 ] correlated best with leaf area having a correlation coefficient (r) of 0.99. Quadratic and linear regression of the data produced thirteen leaf area models. The best five models were derived from single dimensional measurement product and sum of length and width of either lamina length or width. The five top models were recommended for leaf area estimation of Irvingia gabonensis but for ease of application, model 13 (Y = 0.2309x2- 2.5694x + 67.268: R 2 = 99%) was preferred for its simplicity. The models developed and recommended in this study can be adopted for rapid and accurate estimation of adaxial leaf area of I. gabonensis under field conditions.