Factors Influencing Early Seedling Vigor of Shrunken‐2 Maize 1

Hybrids with the shrunken-2 (sh2) gene are being used to provide high sugar maize (Zea mays L.) for human consumption. A major factor limiting their acceptance by the processing industry is reduced germination and low seedling vigor. To examine these deficiencies of high sugar (sh2) maize germination percentage and relative rootshoot growth were measured for a systematic series of inbreds and hybrids at four germination temperatures for both round and flat kernels. Germination differences among sh2 lines were highly significant, with two hybrids meeting criteria for field use. Within lines and temperature regimes the larger, round grade of kernels tended to perform better than the smaller, flat grade. However kernel weight of the sh2 parents and relationship to weight of their standard (sugary) counterparts did not give an indication of their performance in hybrid combination.