Effect of Seeding Date, Plant Density, Moisture Availability, and Soil Nitrogen Fertility on Maize Kernel Breakage Susceptibility1

Abstract

The objectives of this study were to evaluate seeding date, plant density, moisture availability, and soil N fertility effects on maize (Zea mays L.) kernel breakage susceptibility. Three hybrids within each of three relative maturity (RM) groups (90, 100, 110 days by Minnesota Relative Maturity Rating System) were grown in separate seeding date and plant density studies at Arlington, WI [Plano silt loam (fine‐silty, mixed, mesic, Typic Argiudoll)], in 1983 and 1984. Maize was seeded four times at 10‐day intervals beginning 1 May. Average densities were 1.75,3.75,5.75, and 7.75 plants m−2. Hybrids were also evaluated in separate irrigated and dryland trials at Hancock, WI [Plainfield sandy loam (mixed, mesic, Typic Udipsamment)]. In a soil N study, grain samples were collected from an experiment at Arlington in which three N rates (0,11, and 22 g m−2 were applied. Grain was combine‐harvested at 25% kernel moisture (except at Hancock where moistures ranged from 21 to 32%) and dried at 82°C in 1983 and 60°C in 1984. Kernel breakage susceptibility, test weight and kernel weight, volume, density, and grain yield were measured. Delayed planting, high plant densities, and low applied N increased kernel breakage susceptibility. At Hancock, higher kernel breakage susceptibility occurred with irrigated‐ vs. dryland‐produced maize. Kernel physical parameters measured were not closely related to kernel breakage susceptibility, except in the soil N study, where the largest range occurred for each variable. The 110‐day RM hybrids had lower kernel breakage susceptibility than 90‐ and 100‐day RM hybrids.