Effect of Late Nitrogen Fertilization on Grain Yield and Grain Filling in Corn

J A Fernandez,I A Ciampitti

doi:10.4148/2378-5977.7776

Abstract

Effect of Late Nitrogen Fertilization on Grain Yield and Grain Filling in Corn

Highlights

In corn, a strong connection was documented between plant N demand and final grain yield (Ciampitti and Vyn, 2013)
A positive trend was found between the year of release of the hybrid and yields, with greater yields for the modern hybrid (i.e., 206 bu/a for P1197)
For 2017 and all treatment combinations, grain number (GN) and grain weight (GW) were both positively correlated with final grain yield (R2 = 0.58 and R2 = 0.43, respectively) in agreement with other previous studies (Andrade et al, 1996) (Figure 1A and B)

Summary

Yield improvement in corn has been accompanied by an increase in plant nitrogen (N) uptake. To evaluate the effect of late-season N applications in distinct corn genotypes, grain yield and grain filling parameters were evaluated in field experiments under early and late N regimes during 2017 and 2018 growing seasons. Hybrids with different release years (3394, 1990s; P1151, 2000s; and P1197, 2016) and contrasting N application scenarios (including a zero-N control) were evaluated at the Kansas State University Ashland Bottoms Research Farm, Manhattan, KS. Results showed that under N stress conditions, the absence of N fertilization in corn significantly reduced yields, by affecting both grain number (GN) and grain weight (GW). A positive trend was found between the year of release of the hybrid and yields, with greater yields for the modern hybrid (i.e., 206 bu/a for P1197). Evaluations across altered sourcesink ratios are needed in order to investigate whether differential responses to lateseason N are determined by variations in the availability of assimilate

Introduction

Procedures

Results

Conclusions