Mixture Experiments and their Application in Agricultural Research

The present study was designed to show the applicability of Mixture designs in Agricultural Research System and to fit an appropriate mixture regression model making response variables as functions of the proportions of the mixture components. Data on four components namely neem oil, garlic oil, clove oil and tobacco extract (ml) were collected from field experiment conducted by Honeybee Research Institute, NARC. The main goal of the experiment was to check whether blending two components have any synergistic effect on honey yield. The results of the mixture regression showed that the positive interaction coefficients of blending components neem oil*garlic oil (1.10) and neem oil*tobacco extract (6.73) were smaller than their individual coefficients which indicated that combining these components will not have significant impact on honey yield. Negative interaction coefficients of neem oil*clove oil (-5.11) and garlic oil*clove oil (-15.86) signaled no significance meaning that they were antagonistic towards one another and will not contribute in increasing honey yield. The positive interaction coefficient of the blending component clove oil*tobacco extract (16.99) shows synergistic effect of these components on honey yield implying that honey yield can increase when clove oil and tobacco extract are blended.