Posições de mudas em bandejas de poliestireno e variabilidade na produção de alface

Abstract

The scientific development has the aim of executing experiments with such quality so that obtained results are accepted and recommended. The quality of an experiment can be described through statistics, ascribing it reliance on the obtained data, being the experimental error one of the parameters the evaluations of such quality. Therefore, the present work aimed at verifying the interference of different positions of seedlings on polystyrene trays on the normality and homogeneity of the errors in experiments carried out in different environments of lettuce production. Six experiments were carried out in the Departamento de Fitotecnia da Universidade Federal de Santa Maria in the summer (2006-2007) and fall winter (2007) with the lettuce crop, cultivar Vera two with seedling production in a greenhouse and four with the production of plants, two in a plastic structure and two in the field, the treatments were defined by 12 different positions of the seedlings on the tray of production. The analyzed variables in the seedling production and after their transplant to the environments were the fresh and dry phytomass of leaves and roots (g) and the fresh and dry phytomass of leaves (g), respectively. Presuppositions of errors normality and homogeneity were tested being compared to the averages of each treatment, as well as the conjoint analysis of the experiments. The different positions of the lettuce seedlings on the production trays did not significantly interfere in the experimental error estimative in the carried out experiments in plastic greenhouse and in the field. The central positions of seedlings was contributive in the final media of the lecttuce plants in greenhouse and in the field. In the summer experiments, the recommendations should be carried out individually to each environment, while in the fall winter experiments they can be generalized to both production environments.