Preliminary evaluation of field factors affecting amino acids in sugarcane juice

Amino acid in simulated mixed sugarcane juice were measured in 23 trials in the Cairns, Burdekin and Mackay districts. Amino acids were influenced by field factors including N fertiliser application rate, location, soil moisture stress and sugarcane variety. Asparagine was the amino acid which was most sensitive to these field factors. Total amino acid was slightly less responsive than asparagine to field changes. The prospect of analysing first expressed juice for amino acid at the factory as an indicator of N nutrition status of sugarcane appears promising. Such a program could assist canegrowers to optimise their fertiliser input by providing a benchmark.