“…Additionally, the application of orthogonal contrasts is an alternative way of doing statistical analysis on data from experiments without a definite structure, like the experiments with additional treatments. The objective of this paper review was to justify the application of the single degree of freedom orthogonal contrasts in the analysis of experimental data from non-conventional experiments, recently published by Nogueira & Corrente (2000) and Corrente et al (2001). Scheffé (1959), Winer (1971), Steel & Torrie (1981), Mead (1988) and Hinkelmann & Kempthorne (1994), among others, define a contrast between treatment means, represented by Y, as a linear function that can be estimated, considering an equal number of replications for all treatments, as follows: , and e ij the experimental error, so that e ij ~ N(0, σ 2 ) and independent of each other.…”