USING RESIDUAL ANALYSIS TO VALIDATE WATERMELON (Citrullus lanatus) DATE OF PLANTING EXPERIMENT MODELS - OKEKE, K. C.; IBRAHIM , A.; IBEGBULEM , J. A.; AYUBA, I. A.; YUSUF , A. A.; HARUNA , A.; ORJI, P. O. (The Faculty of Agriculture Obafemi Awolowo University, Ile-Ife, Nigeria., 2020)