Row Width and Plant Density Effect on Corn Forage Hybrids

Information is needed on the agronomic factors that maximize yield and quality of recently developed corn (Zea mays L.) forage hybrids. This study was conducted to determine the effect of row width (76, 56, and 38 cm) and plant density (64200, 79000, and 88900 plants ha−1) on forage yield and quality of forage specialty corn hybrids and a dual-purpose hybrid. Two of the forage hybrids evaluated were leafy hybrids, and the other one was characterized as a nutridense hybrid. The increase in forage dry matter (DM) yield when row width was narrowed from 76 to 38 cm was similar for the forage hybrids and the dual-purpose hybrid (1.1 and 0.9 Mg ha−1, respectively). However, there were significant differences in response to decreased row width between the two leafy hybrids evaluated. The narrow row production system did not impact corn forage quality nor was there a hybrid × row width interaction. As plant density increased from the lowest level to the highest, forage DM yield increased by 1.6 Mg ha−1, DM digestibility decreased from 652 to 641 g kg−1, crude protein decreased from 76 to 72 g kg−1, acid detergent fiber increased from 259 to 270 g kg−1, and neutral detergent fiber increased from 441 to 456 g kg−1. In addition, there was no hybrid × plant density interaction for these parameters. It was concluded that these forage hybrids will react to changes in row width and plant density similar to dual-purpose hybrids.