Genotype ✕ Popping Method Interaction for Expansion Volume in Popcorn

Abstract

Expansion volume, defined as the volume of popped corn per gram of unpopped corn, is considered the most important quality trait in popcorn (Zea mays L.). The increasing popularity of microwave popcorn has necessitated the development of cultivars for use in both conventional and microwave popping. Information on expansion volume of popcorn genotypes using both popping methods is not available in the literature. This study investigated the presence of a genotype ✕ popping method interaction for expansion volume and its components in popcorn. Eleven commercial popcorn hybrids, one flint corn ✕ popcorn inbred line cross, and one open‐pollinated popcorn variety were grown in isolation in 1988. Seed harvested from each genotype was divided equally into large‐ and small‐kernel samples that were evaluated for expansion volume, popped kernel (flake) size, and percent unpopped kernels in conventional and microwave popping. All genotypes performed better in conventional popping than in microwave popping. Significant differences existed among genotypes for expansion volume and flake size. A significant genotype ✕ popping method interaction was detected for expansion volume, flake size, and percent unpopped kernels. Therefore, breeders utilizing germplasm similar to that which we studied with the dual objective of developing cultivars for conventional and microwave popcorn markets should conduct evaluations for expansion volume using both popping methods.