Leaf

Abstract

Leaf area and specific leaf wr (SLA) are important parameters in many agmwmic and ecological processes, but can be difficult and expcnsivt to measure. This study was made to test simplified meth- ods of estimating pearl millet [Penmiserum ghcum (L.) R. Br.] leaf area md SLA. Leaf length, maximum width, area, and dry mass data wen obtained at 2-wk intervals from plants grown in 75-L pots. Pots contained 85 kg of acidic, Pdeficient Betis sand (sandy, sili- cious, thennic Psrmmentic Paleustalf) and were treated with four P levels and two water treatments (stressed and nonstressed). Individ- ual kaf uer was estimated nondestndively with the following quatiotls: Indivlduai leaf area and whole plant leaf area were calculated from leaf dry mass by the following linear and nonlinear equations: Residual errors indicated that the nonlinear equation wm more ec- curate for area estimation of small leaves (50.20 g), and that I d area data were heleroscedastic. Leaf dry mass was also used to cal- culate SLA by the nonlinear equation SLA = 176.7 X Loaf ~ n n s s ~ ~ ' ' ~ (R' - 0.918), which gave excellent fit to experimental data independent of harvest date, P level and watering treatment. Our results demonstrate that pearl millet leaf arm and SLA can be accurately estimated and easily simulated from simple regression equations.