Narrow row maize cultivation increased grain and forage yield of hybrids in Ohio and Pennsylvania

Abstract

AbstractAlthough there has been a resurgence in interest among farmers in producing narrow row hybrid maize (Zea mays L.) in the Eastern UnitedStates, agronomic recommendations for modern hybrids are limited. To address this issue, field trials were carried out from 2016 to 2018 in Ohio and Pennsylvania (10 unique site‐year combinations), aiming to answer the following questions: (i) Do modern hybrids differ in their response to narrow (38 cm) and conventional (76 cm) row spacing? (ii) Is there a yield increase for narrow row production? The study was planted in a split‐plot randomized complete block design with four replications. The whole plot factor was row spacing, and the subplot factor was hybrid. Two hybrids (P0506AM and P0604AM) were in an “early”‐season group, and two hybrids (P1197AM and P1443AM) were “full”‐season hybrids. Both P0506AM and P1443AM were identified as AQUAmax hybrids and had superior seed company drought tolerance ratings over their maturity pairing counterpart. Grain and forage yield were 4% and 8% greater, respectively, for the narrow row spacing across hybrids. Hybrid differences in drought tolerance designation did not result in grain or forage yield differences under varied row spacings. There was no hybrid × row spacing interaction. In most site‐years, P1197AM hybrid produced the greatest grain and forage yields, though P1443AM and P0506AM were similar in most cases. Results suggest a minor advantage in yield (≤8%) from narrow rows in Ohio and Pennsylvania, though other considerations that include cost to conversion should be considered prior to adoption.