A case study to teach the diagnostic process: Determining the cause of chlorosis in a crop of cut dicentra

Abstract

This universally accessible, Web-based decision case presents the challenge of determining the cause of foliar chlorosis in a crop of dicentra (Dicentra spectabilis) being forced as a cut flower for Valentine's Day sales. The case study serves as a tool to promote the development of diagnostic skills for production dilemmas, including nutritional disorders, disease problems, and evaluation of the appropriateness of cultural practices. Cut dicentra is a minor crop and standard production practices are not well established. Solving this case requires that students research production protocol, as well as nutritional and pest problems, and determine whether they have enough information to recommend a solution. In this case study, a grower at Flint's Flower Farm must determine the cause of foliar chlorosis that is slowly appearing on about half the plants of her cut dicentra crop. The condition could be related to a number of possible problems, including a nutritional disorder, disease infection, or production practices. Resources are provided to aid students in gathering background information. Data accumulated by the grower are presented to allow students to eliminate unlikely solutions logically. The solution, which is unique to this crop, is provided along with detailed objectives and discussion points in teaching notes. This case study is complex in nature and is intended for use with advanced students in upper-level undergraduate courses of floriculture production, nutrient management, and plant pathology who have been previously exposed to the diagnostic process.