Effect of Endosperm Mutants on Germination and Early Seedling Growth Rate in Maize (Zea mays L.)1

Endosperm mutants in three near‐isogenic backgrounds of maize ( Zea mays L.) were used to determine their effect on germination and early seedling growth. Two environments were utilized: average greenhouse temperature regimes (20 to 25 C) and 15 C in a controlled environment chamber. Floury‐1 had a significantly greater early seedling growth rate than normal in both environments. while sugary‐1 had a significantly slower seedling growth rate in both environments, all mutants showed significantly slower seedling growth rates than normal at 15 C. Shrunken‐1 showed a significantly lower maximum number of plants germinated than normal under greenhouse conditions. Sugary‐1 was significantly different from normal in both environments.