Light interception, leaf area and biomass production as a function of the density of maize plants analyzed using mathematical models

Resumo

Mathematical models were tested to correlate the leaf area index (LAI) of maize to the percentage of light intercepted by the canopy (% LIC) and this with the total dry matter of aerial parts (TDM), as well with the grain yield (GY). The experiment was conducted in a randomized block design, with four replications. The treatments consisted of hybrid maize at five plant densities: 4.0, 2.66, 2.0, 1.6, and 1.3 plants per m² (pl m^-2). At densities of 4.0 and 2.66 pl m^-2, the average LAI and TDM did not differ among themselves but were significantly higher than those presented at the densities of 2.0, 1.66 and 1.3 pl m^-2, which also did not differ among themselves. The number of corncobs per plant (cob pl^-1) and GY behaved similarly. The LAI grew exponentially with the plant density. For all ages of plants, the exponential model fit well with the % LIC values according to the LAI and also fit well to the data of dry mass as a function of % LIC. GY depending on the density fit well to quadratic, exponential straight line and logarithm-modified equations, and the number of cobs per plant depending on the density fit well to hyperbolic and exponential-modified equations.