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Seed treatments for control of root rots in spring wheat in Bonneville County, ID, 2004
Get PDFThe trial was established in a commercial dryland field with 6 in. standing stubble in Bonneville County, ID. The field
had been cropped to wheat and barley in the preceding years using a one pass Case IH ATX Concord direct seed drill. The
soil type was a Tetonia silt loam classified as a coarse -silty, mixed, calcic, pachic cryoboroll with a pH of 6.3 and 2.6%
organic matter. Experimental units (5 x 30 ft) were arranged in a randomized complete block design with 4 replicates.
Fungicide seed treatments were applied as a slurry (18.4 fl oz/100 lb seed) on 9 Apr at rates indicated in the table. Seed for
the check plots was only treated with water. Seeds were planted at 60 lb/A on 27 Apr with a direct-seed drill with Conserva
Pak openers. The openers placed the fertilizer (75 lb/A N, 25 lb/A P 2O5 , and 16 lb/A S) 1.5 in. below the seed in a one-pass
operation. The weeds and volunteer wheat were controlled by a 10 fl oz/A Round-up treatment on 25 Apr and a 0.3 oz/A
application of Ally Extra on 21 May. Stand counts were recorded on 21 May at Feekes growth stage 1 (3 leaves). Fifteen
plants per experimental unit were dug on 6 Jul at Feekes growth stage 10.1 to 10.5 (late boot to flowering) and rated for root
diseases. Root disease severity was established by placing the plants into the following categories: 0 = none, 1 = trace, 2 =
slight, 3 = moderate, and 4 = severe. Plots were harvested 29 Sept with a small plot combine. Yield and test weight were
determined. Data were analyzed using the general linear models procedure (Proc GLM) in SAS. Fisher's Protected LSD was
used for mean comparisons
Synthetic- and bio-polymer use for runoff water quality management in irrigation agriculture
Get PDFLow concentrations of synthetic- or bio-polymers in irrigation water can nearly eliminate
sediment, N, ortho- and total-P, DOM, pesticides, micro-organisms, and weed seed from runoff. These
environmentally safe polymers are employed in various sensitive uses including food processing, animal
feeds, and potable water purification. The most common synthetic polymer is anionic, high purity
polyacrylamide (PAM), which typically provides 70-90% contaminant elimination. Excellent results are
achieved adding only 10 ppm PAM to irrigation water, applying 1 -2 kg ha. -1 per irrigation, costing
12 kg -1 . Biopolymers are less effective. Using twice or higher concentrations, existing biopolymers
are ,r=60% effective as PAM, at 2 - 3 times the cost. A half million ha of US irrigated land use PAM for
erosion control and runoff protection. The practice is spreading rapidly in the US and worldwide. Interest
in development of biopolymer surrogates for PAM is high. If the supply of cheap natural gas (raw material
for PAM synthesis) diminishes, industries may seek alternative polymers. Also "green" perceptions and
preferences favor biopolymers for certain application
Linking manure properties to phosphorus solubility in calcareous soils: Importance of the manure carbon to phosphorus ratio
Get PDFLand application of manure can increase P transfer in runoff,
although the risk depends in part on the characteristics of the manure.
We assessed this for calcareous soils using manures from swine (Sus
domesticus) fed one of five barley varieties (Hordeum vulgare L.),
including four low phytate mutants and a normal variety, to produce
manures with a range of total P (6.8-4.9 g P water-soluble P
(4.3-8.0 g P kg-'), total N/P ratios (2.5:1-5.5:1), and total C/P ratios
(31:1-67:1). Two experiments were conducted. First, manures were
incorporated into three soils on a N (150 mg N kg-' soil) or P (27.5 mg
P kg-1 soil) basis three times during a 7-wk incubation. Second, 10
additional soils were incubated for 2 wk following a single P-based
manure application (82.5 mg P kg-i soil). Water and NaHCO3 (Olsen)
extractable P were determined at regular intervals, with microbial
P determined by fumigation-extraction after each incubation. For
N-based application (i.e., variable P amendment), extractable P increased
with total P applied. For P-based applications, the increase
in soil P was more closely correlated to microbial P concentration than
manure P composition or soil properties. These results suggest that
stimulation of the microbial biomass by added organic C is important
in determining soil P solubility following manure application
Effect of added sugar on preference and intake by sheep of hay cut in the morning versus the afternoon
Get PDFRuminants prefer hay cut in the afternoon to hay cut in the morning, presumably because hay cut in
the afternoon contains higher concentrations of non-structural carbohydrates than hay cut in the
morning. We determined if adding sugars (glucose and sucrose) to ground hay would account for
differences in preference and affect intake of hay. Alfalfa hay cut either in the afternoon (PM) or the
following morning (AM) was used in the trials. Glucose and sucrose were added to AM hay (AMS) to
make its sugar content similar to PM hay. During the first trial, lambs received a choice of either: (1)
AM and PM hay; (2) AMS and PM hay; or (3) AMS and AM hay. Lambs preferred PM to AMS or AM
hay. We also studied how increasing the concentration of added sugars affected preference for hay.
Lambs received a choice of AM hay and AM hay with either 1, 2, 3, or 4% added sugar. On the first day
of the trial, lambs ate similar amounts of each hay type, regardless of the amount of sugar added. By the
end of the trial, lambs preferred hay with 2, 3, or 4% added sugar compared with AM hay without added
sugar. During the intake trial, lambs ate similar amounts of AM, AM hay with added starch and sugar
(AMSS), and PM hay. After the intake trial, a final preference trial determined that prolonged exposure
to AMSS hay increased preference for AMSS hay compared with AM hay. Our results indicate that
preference for PM hay is likely related to increased levels of sugars, such as glucose and sucrose, and
that lambs learn about the post-ingestive benefits of exogenous sugars added to hay
Numbers of fecal streptococci and Escherichia coli in fresh and dry cattle, horse, and sheep manure
Get PDFLivestock are known contributors to stream pollution. Numbers of fecal streptococci and Escherichia coli in
manure naturally deposited by livestock in the field are needed for activities related to bacterial source tracking and determining
maximum daily bacterial loading of streams. We measured populations of fecal streptococci and E. coli in
fresh and dry manure from cattle (Bos taurus L.), horses (Equus caballus L.), and sheep (Ovis aires L.) on farms in
southern Idaho. Populations of indicator bacteria in dry manure were often as high as that in fresh manure from horse
and sheep. There was a 2 log 10 drop in the population of fecal coliform numbers in dry cattle manure from cattle in
pastures but not from cattle in pens. Bacterial isolates used in source tracking should include isolates from both fresh
and dry manure to better represent the bacterial source loading of streams
Erosion: Irrigation-induced
Get PDFSoil erosion is caused by wind, tillage, precipitation,
or irrigation. Erosion caused by irrigation, usually
termed 'irrigation-induced erosion,' can be the most
damaging because it affects many of the most productive
soils in the world. These are the soils of arid
irrigated regions, which typically have thin A horizons,
little organic matter, and weak structure,
making them highly erodible. Moreover, these soils,
once degraded, recover very slowly. Irrigation induced
erosion occurs as an unintended consequence
of irrigation for improved crop production
Plant analyses and interpretation
Get PDFPlant analysis historic beginnings are generally attributed to T. de Saussure (1804)
following studies by van Helmont, Joseph Priestly, Henry Cavenish, and Antonine
Lavoisier. de Saussure showed that the composition of plant ash varied with the
part analyzed, with the age of the plant, and with the soil upon which the plant
grew. The ash was chiefly composed of alkalis and phosphates. Erasmus Darwin
in his 1800 book, Phytogia: The Philosophy of Agriculture and Gardening (London,
J. Johnson) wrote that both nitrogen (N) and phosphorus (P) were essential
components of plants. In 1833, the Fifth Duke of Richmond showed that the value
of bone meal fertilizing was due to its P component rather than calcium (Ca), although
Justus von Liebig (1852) is generally considered the father of soil fertility.
Readers interested in additional historic information should consult Ulrich (1948),
Bear (1948), and Russell (1976)
Phosphorus compounds in sequential extracts of animal manures: Chemical speciation and a novel fractionation procedure
Get PDFPollution of water bodies by phosphorus in runoff from
soil amended with animal manures is one of the greatest
threats to water quality in developed countries. The
environmental fate of manure phosphorus is determined
in part by its chemical composition, yet extraction procedures
to assess this are poorly developed and provide no
structural information. We used solution 31 P NMR
spectroscopy to quantify phosphorus compounds in
sequential extracts of three contrasting manures (broiler
litter, beef-cattle manure, swine manure). Using a procedure
originally developed for soils, but commonly applied to
manures, phosphorus was extracted sequentially with
deionized water, 0.5 M NaHCO 3, 0.1 M NaOH, and 0.5 M
HCI. Water and NaHCO 3 extracted readily soluble compounds,
including phosphate, phospholipids, DNA, and simple
phosphate monoesters, which are mobile in soil and
biologically available. In contrast, NaOH and HCI extracted
poorly soluble compounds, including phytic acid (myoinositol
hexakisphosphate). The latter is immobile in soil
and of limited biological availability. Based on these results,
we developed a simplified two-step fractionation procedure
involving extraction of readily soluble phosphorus in 0.5
M NaHCO3 followed by extraction of stable phosphorus in
a solution containing 0.5 M NaOH and 50 mM EDTA.
This revised procedure separates manure phosphorus
into structurally defined fractions with environmental
relevance and will facilitate research on this important
aspect of environmental science
Soil quality: to regulate or to manage?
Get PDFThe concept of soil quality was conceived in the early 1990s as a parallel to those of air
and water quality in response to concerns about soil 'health,' sustainability and environmentally
`friendly' crop production. The concept has the potential to be used by researchers to link soil
research issues to broader environmental issues when applying for funds.
However, unlike air and water, soils have no defined 'pure' state against which measures can be taken
and comparisons made. The physical, chemical and biological composition of soils varies widely and
no single attribute or soil type can be established as a standard. The choice of appropriate soil
properties and their standards depends on the use to which the soil is put.
We suggest concentrating on quality management of the soil, rather than managing generically-chosen
soil properties, collectively called soil 'quality'. Quality management puts the onus on managers to
use the technical tools that are readily available to manage soils and landscapes, and on scientists to
develop new tools
Determination of phosphorus source coefficients for organic phosphorus sources: Laboratory studies
Get PDFPhosphorus losses in runoff from application of manures and biosolids
to agricultural land are implicated in the degradation of water
quality in the Chesapeake and Delaware Inland Bays. We conducted
an incubation study to determine the relative P solubility and bioavailability,
referred to as P source coefficients (PSCs), for organic P
sources, which are typically land-applied in the Mid-Atlantic USA.
Nine organic and one inorganic (ICH2PO4) P amendments were applied
to an Evesboro loamy sand (mesic, coated Typic Quartzipsamments)
at a rate of 60 mg P kri and incubated for 8 wk with subsamples
analyzed at 2 and 8 wk. There was an increase in Mehlich-3
P (M3-P), water-soluble P (WS-P), iron-oxide strip extractable P
(Fe0-P), and Mehlich-3 P saturation ratio (M3-PSR) with P additions,
which varied by P source. The trend of relative extractable WS-P,
Fe0-P, and M3-P generally followed the pattern: inorganic P > liquid
and deep pit manures > manures and biosolids treated with metal
salts or composted. We found significant differences in the availability
of P from varying organic P sources. The use of PSCs may be beneficial
when determining the risk of P losses from land application of manures
and other organic P sources and could be used in risk assessments
such as a P site index. These PSCs may also be useful for determining
P application rates when organic P sources are applied to P deficient
soils for use as a fertilizer source