Analysis of variance was performed for each response variable
using the full models where P values indicated if the terms were
significant. In general, values of coefficients of determination R2
and R2
adj > 0:75 indicated the goodness of fit of the quadratic models
to the experimental results (Chauhan & Gupta, 2004). The high
values of R2 obtained indicated that none of the predicted models
had a significant lack of fit.