Money matters (II): costs of maize inbred line conversion schemes at CIMMYT using conventional and marker-assisted selection

Abstract

This article presents selected results of a study carried out in Mexico at the International Maize and Wheat Improvement Center (CIMMYT) to compare the cost-effectiveness of conventional and biotechnology-assisted maize breeding. Costs associated with the use of conventional and marker-assisted selection (MAS) methods at CIMMYT were estimated using a spreadsheet-based budgeting approach. This information was used to compare the costs of conventional and MAS methods for a particular breeding application: introgressing an elite allele at a single dominant gene into an elite maize line (line conversion). At CIMMYT, neither method shows clear superiority in terms of both cost and speed: conventional breeding schemes are less expensive, but MAS-based breeding schemes can be completed in less time. For applications involving tradeoffs between time and money, relative profitability can be evaluated using conventional investment theory. Using a simple model of a plant breeding program, we show that the optimal choice of a breeding technology depends on the availability of operating capital. If operating capital is abundantly available, the "best" breeding method will be the one that maximizes the net present value (i.e., MAS), but if operating capital is constrained, the "best" breeding method will be the one that maximizes the internal rate of return (i.e., conventional selection). This insight may help to explain why private firms tend to invest more aggressively in biotechnology than public breeding programs, which are more likely to face budgetary constraints.