Use of growth analysis to describe the N fertiliser responses of maize ( Zea mays L.) hybrids

Abstract

Using the classical and functional methods of growth analysis, the effect of mineral N fertiliser (0, 80, 160 and 240 kg ha −1 ) on the dynamics of growth and growth parameters was studied in 2001 and 2002 in a two-factorial, long-term experiment set up in a split-plot design on three maize hybrids with different genotypes, Mv 272 (FAO 280), Mv 355 (FAO 390) and Maraton (FAO 450). The following growth parameters were calculated to characterise the effect of N fertiliser: the absolute growth rate (AGR, ALGR), the relative growth rate (RGR), the leaf area index (LAI), the net assimilation rate (NAR) and the harvest index (HI).Similar tendencies were found for the yield response of maize and the values of the growth parameters as a function of N fertilisation. Based on the results of principal component analysis, multiple regression analysis and discriminant analysis, the parameters AGR, LAI max , ALGR and HI were found to have a decisive influence on the grain yield of maize. It could be concluded from the results that growth parameters can be used to predict the N fertiliser responses of maize in early growth stages.