Use of Euclidean distance to evaluate Pistia stratiotes and Eichhornia crassipes as organic fertilizer amendments in Capsicum annuum

Conventional agriculture is reliant on the application of unsustainably high rates of inorganic fertilizers with detrimental consequences on the environment. The use of invasive aquatic macrophytes as organic fertilizer for crop production represents a unique opportunity for weed control as well as to use this plant material that would typically be disposed of, as a resource instead. Therefore, the goal of the present study was to use Pistia stratiotes and Eichhornia crassipes as organic fertilizer for the growth of a high value vegetable, Capsicum annuum. Furthermore, to evaluate if Euclidean distance can be used as a tool to integrate the data collected into a single meaningful outcome. The results showed that growth on soil amended with plant material from the aquatic macrophytes resulted in improved plant height, number of leaves per plant, leaf length, stalk diameter and the number of fruits produced per plant (characterized by Medium and High OCVs). The outcome from calculation of the Euclidean distance revealed that the best treatments to achieve the desired phenotype were amendments with 100 g P. stratiotes or 400 g E. crassipes. Therefore, it was evident that the tested macrophyte weeds can be used as organic fertilizers to promote plant growth and yield in C. annuum and that assessment of the Euclidean distance is a useful tool to incorporate the findings from a range of parameters into a single summarized outcome.