In this study, we present the results of an original experimental protocol designed to assess the performance in a pluralization task of 52 Italian children divided into two groups: 24 children with developmental dyslexia (mean age 10.0 years old) and 28 typically developing children (mean age 9.11 years old). Our task, inspired by Berko's Wug Test, had the aim of testing the subjects' ability to apply pluralization rules to nonwords in the morphologically complex context of Italian nominal inflection. Results demonstrate that dyslexics display poorer morphological skills in comparison to controls, showing lower accuracy in the task. Furthermore, the dissimilar performances reported by the subjects in the different conditions indicate that the ability to inflect nonwords depends on factors such as the rule's productivity, frequency, and opacity with respect to gender. Finally, the children's performance in this task was significantly related to their reading proficiency, and it could predict accuracy in word reading independently of phonological awareness and working memory.