Corn growth and yield response to starter fertilizer

Description

<p>In previous
research in continuous corn with no-till management, starter fertilizer
consistently increased vegetative plant development rate and plant dry matter
prior to sidedressing and decreased grain moisture. However, increased yield
did not always occur. The objective of my study was to evaluate the effects of
starter fertilizer on plant dry matter and nutrient content throughout the
growing season to determine if differences in these parameters determined early
in the growing season persisted throughout reproductive growth and explained
yield effects. Experiments were conducted in long-term continuous corn
no-tillage fields at SEPAC, NEPAC, and TPAC in 2019 and 2020. At TPAC,
treatments were control and starter, 46 kg N ha^-1 and 18 kg P ha^-1.
At SEPAC and NEPAC, we also evaluated starter fertilizer composition, and the
treatments were control, 3.6 kg N ha^-1 and 8 kg S ha^-1;
N, 34 kg N ha^-1 and 8 kg S ha^-1; NP, N plus 7.5 kg P ha^-1;
and NPK, NP plus 9.5 kg K ha^-1. Starter fertilizer was applied 5 cm
below and 5 cm to one side of the seed. Total N rate was equalized by adjusting
the N application at sidedressing to compensate for the N applied in starter.</p>

<p>Although starter
fertilizer treatment effects differed from those of the control, in most cases
starter fertilizer effects were the same regardless of composition. Hereafter,
‘starter fertilizer’ will refer to the mean of the three starter fertilizer
treatments, N, NP, and NPK for SEPAC and NEPAC or NP in the case of TPAC. Crop
growth rate determined by the number of collared leaves was increased by
starter fertilizer, compared to the control, at all site-years. Starter
fertilizer increased leaf appearance up to one leaf in plots evaluated at the
same point in time and final leaf number was also one more leaf per plant.
Starter fertilizer increased dry matter as early as V4 compared to the control
at SEPAC and TPAC, with differences maximizing around V6-V12. Effects at NEPAC
were inconsistent throughout the season. At reproductive stages the magnitude
of the differences in dry matter decreased until starter fertilizer and control
treatments had similar dry matter at maturity. Before sidedressing, N and P
concentrations were greater with starter fertilizer than the control, but after
sidedressing concentration of these nutrients were greater with control than
starter fertilizer. The differences in N and P concentration between starter
treatments and the control increased in later vegetative stages, but decreased
during reproductive stages and at maturity. Potassium concentration was
generally unaffected by the fertilizer treatments. Plant nutrient content
differences between starter fertilizer treatments and the control were similar
to differences seen with dry matter, despite the differences in nutrient
concentration between starter fertilizer and the control. When compared at the
same growth stage, starter fertilizer treatments and the control, had similar
DM and nutrient concentration and content. Starter fertilizer, compared to the
control, resulted in earlier silking and/or tasseling at all site-years.
Starter fertilizer accelerated vegetative crop development, but this did not
result in substantial differences in dry matter or nutrient content at similar
growth stages, including physiological maturity. Despite this result, increased
grain yield with starter fertilizer, compared to the control, occurred at 3 of
6 site-years and ranged from 300 to 1000 kg ha^‑1. Grain moisture was
decreased by starter fertilizer at 4 of 6 site-years by at least 5 g kg^-1.</p>

Links & Downloads

1. 10.25394/pgs.15078300.v1

Tags

Agronomy

starter fertilizer

Additional Fields

Identifer	oai:union.ndltd.org:purdue.edu/oai:figshare.com:article/15078300
Date	01 September 2021
Creators	Daniela Orjuela (11205333)
Source Sets	Purdue University
Detected Language	English
Type	Text, Thesis
Rights	CC BY 4.0
Relation	https://figshare.com/articles/thesis/Corn_growth_and_yield_response_to_starter_fertilizer/15078300