We discuss and comment on the role agriculture will play in the containment of the CO2 problem and address protocols for terraforming the planet Earth.
A model farm template is imagined as the central methodology. A broad range of timely science news and other topics of interest are commented on.
Tuesday, April 30, 2013
Fertility Needs in High-Yielding Corn Production
The fertility needs of modern corn culture will not be resolved until
we master the biochar protocol which allows sequestering of all
nutrients on a continuing basis from either chemical treatment or
natural decay based release.
In the meantime, corn happens to be our most hungry crop. Thus
fertility is a challenge at best.
We need to perhaps find a way to engineer corn to somehow be a better
citizen as we are completely set up to work with it in particular.
Although advances in
agronomy, breeding, and biotechnology have dramatically increased
corn grain yields, soil test values indicate that producers may not
be supplying optimal nutrient levels. Moreover, many current nutrient
recommendations, developed decades ago using outdated agronomic
management practices and lower-yielding, non-transgenic hybrids, may
Researchers with the
University of Illinois Crop Physiology Laboratory have been
re-evaluating nutrient uptake and partitioning in modern corn
fertilization practices may not match the uptake capabilities of
hybrids that contain transgenic insect protection and that are grown
at planting densities that increase by about 400 plants per acre per
year," said U of I Ph.D. student Ross Bender. "Nutrient
recommendations may not be calibrated to modern, higher-yielding
genetics and management."
The study examined six
hybrids, each with transgenic insect protection, at two Illinois
locations, DeKalb and Urbana. Researchers sampled plant tissues at
six incrementally spaced growth stages. They separated them into
their different fractions (leaves, stems, cobs, grain) to determine
season-long nutrient accumulation, utilization, and movement.
uptake rates were found to be nutrient-specific, they generally
occurred during late vegetative growth. This was also the period of
greatest dry matter production, an approximate 10-day interval from
V10 to V14. Relative to total uptake, however, uptake of phosphorus
(P), sulfur (S), and zinc (Zn) was greater during grain fill than
during vegetative growth. The study also showed that the key periods
for micronutrient uptake were narrower than those for macronutrients.
of the data are numerous," said Matias Ruffo, a co-author of the
paper and worldwide agronomy manager at The Mosaic Company. "It
is necessary that producers understand the timing and duration of
nutrient accumulation. Synchronizing fertilizer applications with
periods of maximum nutrient uptake is critical to achieving the best
fertilizer use efficiency."
Jason Haegele, another
co-author of the paper and post-doctoral research associate at the U
of I added, "Although macro- and micronutrients are both
essential for plant growth and development, two major aspects of
plant nutrition are important to better determine which nutrients
require the greatest attention: the amount of a nutrient needed for
production, or total uptake, and the amount of that nutrient that
accumulates in the grain."
indicated that high amounts of nitrogen (N), potassium (K), P, and S
are needed, with applications made during key growth stages to
maximize crop growth. Moreover, adequately accounting for nutrients
with high harvest index values the proportion of total nutrient
uptake present in corn grain), such as N, P, S, and Zn, which are
removed from production fields via the grain, is vital to maintaining
long-term soil productivity.
In Illinois, it is
common to apply all the P in a corn-soybean rotation prior to the
corn production year.
in Illinois fertilize, on average, approximately 93 pounds of P2O5
per acre for corn, the estimated 80 percent of soybean fields
receiving no additional phosphorus would have only 13 pounds per acre
remaining for the following year's soybean production," said
Fred Below, professor of crop physiology. "Not only is this
inadequate for even minimal soybean yield goals, but these data
suggest a looming soil fertility crisis if fertilizer usage rates are
not adjusted as productivity increases."
Integration of new
findings will allow producers to match plant nutritional needs with
the right nutrient source and right rate applied at the right time
and right place. The same team of scientists is collaborating on a
follow-up study investigating the seasonal patterns of nutrient
accumulation and utilization in soybean production.
nutrient management is a complex process, a greater understanding of
the physiology of nutrient accumulation and utilization is critical
to maximize the inherent yield potential of corn," concluded
partitioning, and remobilization in modern, transgenic
insect-protected maize hybrids" by Ross R. Bender, Jason W.
Haegele, Matias L. Ruffo and Fred E. Below was published in the
January 2013 edition of Agronomy Journal (105:161-170). It is an
open-access article available here. An abbreviated version of
this article, entitled "Modern corn hybrids' nutrient uptake
patterns," was published in Better Crops with Plant Food