Allometric equations for non-destructive biomass estimation of early stage sugarcane plants – Case study in Pernambuco, northeastern Brazil

Brazil recently became the 5th world power, and with a tremendous growing of its population and the resulting needs, this country is facing challenges in providing energy to every sector of its socio-economical activity. The actual global warming concern and the inevitable decline of fossil energy resources has lead to the research and development of new renewable energy sources as well as to the improvement of the already existing ones. Historically, sugarcane occupies a prominent place among the agricultural crops in Brazil and is in a period of increasing demand. The importance of this crop for the Brazilian economy makes research and development of new varieties and new agricultural techniques a priority. This study aimed to develop a non-destructive method to assess biomass production of live sugarcane plantations at an early stage of development. It highlighted the more relevant non-destructive parameters at different stages of the crop (60, 90, 120 days after planting) to evaluate above-ground biomass by establishing multiple linear regression models. The relevance of the following parameters were established: the diameter at ground level and the dimensions of the leaf F(0). The study was first carried out considering sugarcane as a species and then by comparing equations for five different sugarcane genotypes (varieties). It also assessed the feasibility of developing allometric equations that would be a useful tool to estimate root biomass from more easily measured above-ground plant parameters.