Identification of the best treatment combination for seedling production through fuzzy logic model and Pareto dominance criterion

Abstract

The present study consists of the development of a fuzzy logic model for categorizing seedlings produced using various combination of potting mix and pot volume and identification of the best combination of treatment for the large scale production of seedlings for mechanical transplanting using Pareto dominance criterion.  A fuzzy logic model with simple expert system rules was developed to categorize the seedlings based on its dry weight of root and shoot biomasses.  The suitable membership function for the model was selected by picking up the shape of the membership function from the list of families and fine tuning the values of parameters of the function.  The model assigned a rational value called biomass growth index (BGI) between 0 and 10 to the seedling such that the seedling with higher growth of both root and shoot biomasses was assigned higher value of BGI and vice versa.  The categorization ability of the developed model was found to be reasonably good and it could be used for the evaluation of growth of seedlings produced from various treatments just prior to transplanting.  The best combination of potting mix and pot volume for the large scale production of seedlings was identified considering BGI of the seedlings, the cost of preparation of pots, and the weight of pot using Pareto dominance criterion.  Among the set of non-dominated solutions, paper pots of 50 cm³ volume filled with mix of 25% vermicompost and 75% sand and soil in equal proportion by volume was selected for the large scale production of the seedlings of tomato, eggplant, and chili peppers.  The proposed fuzzy logic model is very easy to develop and when it is coupled with Pareto dominance criterion, it can be effectively used in the decision support system for the identification of the best combination of treatment for the seedling production.

Keywords: Fuzzy logic model, membership function, Pareto dominance, root:shoot ratio, biomass growth