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Advances in Data Processing for Open-path Fourier Transform Infrared Spectrometry of Greenhouse Gases.
Get PDFThe automated quantification of three greenhouse gases, ammonia, methane and nitrous oxide, in the vicinity of a large dairy farm by open-path Fourier transform infrared (OP/FT-IR) spectrometry at intervals of 5 minutes is demonstrated. Spectral pretreatment, including the detection and correction of the effect of interrupting the infrared beam is by a moving object, and ways of correcting for the effect, and correction for the nonlinear detector response are applied to the measured interferograms. Two ways of obtaining quantitative data from OP/FT-IR data are described. The first, which is installed in commercial OP/FT-IR spectrometers, is based on classical least squares (CLS) regression and the second is based on partial least squares (PLS) regression. It is shown that CLS regression only gives accurate results if the absorption features of the analytes are located in very short regions where lines due to atmospheric water vapor are absent; of the three analytes examined, only ammonia fell into this category. On the other hand, PLS regression allowed what appeared to be accurate results to be obtained for all three analytes
Phosphorus Removal by Silage Corn in Southern Idaho
Get PDFCorn silage is the predominant crop in Idaho used for
recovering phosphorus (P) that has accumulated in soils
from dairy manure applications. However, little is known
about how much P and other nutrients are being recov-
ered under Idaho conditions. The objective of the study
is to estimate P removal by irrigated corn silage crops
cultivated throughout southern Idaho with variable soil
test P concentrations, and to identify effects of increasing soil test P on tissue concentrations of P and on plant
P uptake.
Forty-two different corn silage fields in 2008 and
2009 were selected throughout southern Idaho for soil
and whole plant sampling at harvest. Soils were ana-
lyzed for Olsen P, plant tissue was measured for total P
content, and dry and wet yields were calculated based
on field weights and drying of plant tissue
Experimental Sugar Beet Cultivars Evaluated for Resistance to Bacterial Root Rot in Idaho, 2008
Get PDFThirty-six experimental sugar beet cultivars were grown in a commercial sprinkler-irrigated sugar beet field near
American Falls, ID where potatoes were grown in 2007. The plots were planted on 21 Apr 08 and managed according to
standard cultural practices. Plants were free of foliar and root disease symptoms. Four roots representative of each cultivar
were hand topped and harvested on 1 Oct. The roots were then placed in a cold room at 3°C and 90% relative humidity until
they were assayed on 7 Jan 09. The roots were washed, dipped in 0.6% sodium hypochlorite solution for 1 min, rinsed in
sterile reverse osmosis water, and then air dried in a laminar hood. A cross section of the root 8-10 mm thick and 45-70 mm
in diameter was cut just below the widest portion of root and placed in a Petri dish on sterile filter paper moistened with sterile
tap water. A 2-mm diameter and 3-mm deep hole was created with a sterile tooth pick in the center of the root slice. A sterile
tooth pick was then dipped in a 48-hr old culture of Leuconostoc mesenteroides subsp. dextranicum B322 grown on MRS
media at 30°C and placed in the hole along with a drop of sterile tap water. Four additional root slices served as the non-
inoculated check (no bacteria inoculated). The root slice/Petri dish combination was placed in a plastic bag and incubated at
30°C. The experiment was a randomized complete block design with four replications (1 root slice = 1 replication for each
cultivar). The diameter of rotted root area was recorded after 72, 96, and 120 hr. Bacteria from the lesions in each replication
were re-isolated by streaking onto MRS to prove only L. mesenteroides was present. Data were analyzed using the general
linear models procedure (Proc GLM-SAS), and Fisher’s protected least significant difference was used for mean comparisons.
The plants from which the roots were collected were healthy in appearance (no signs or symptoms for any disease
problem). The root slices in the non-inoculated check treatment developed no rot. On the inoculated slices, only L.
mesenteroides was isolated from the bacterial rot lesions. After 120 hr, bacterial rot ranged from a high of 18.3 mm on
cultivar HM080011 to a low of 2.8 mm on cultivar B-40. These data should provide a starting point in the search to identify
resistance to L. mesenteroides in sugar beet. Given the range of responses, improving sugar beet cultivars for resistance to
bacterial rot should be possible
Evaluation of Nitrogen and Phosphorus Fertilizer Placement With Strip Tillage for Irrigated Pacific Northwest Corn Production
Get PDFNutrient placement options with strip tillage (ST) can potentially improve plant nutrient utilization and increase crop yield compared to conventional fertilizer placement practices under conventional tillage (CT). The effects of tillage practice and nitrogen (N) and phosphorus (P) placement on grain yield, biomass yield (whole plant, grain + cobs + stover), and N and P uptake of field corn (Zea mays L.) were assessed on four sites during 2007 and 2009 at the USDA-ARS Northwest Irrigation & Soils Research Laboratory at Kimberly, ID. During each year, two locations (eroded and not eroded from furrow irrigation) were utilized as study locations. Band placement of fertilizer with ST increased corn grain yield by 12.5 % (11 bu/acre) and 25.9% (26 bu/acre) on the eroded locations compared to broadcast N and P and 5cm×5cm N under CT in 2007 and 2009, respectively. These increased yields also resulted in better utilization of N and P by the plant. Reduced tillage costs of ST with associated band placement of N and P could increase the economic productivity of many acres of land in the Pacific Northwest
Small Grain Residue Management Effects on Soil Organic Carbon: A Literature Review
Get PDFImpact of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) straw removal from fields on soil organic C (SOC) is a concern. Increased animal populations and potential development of cellulosic ethanol production could increase the removal of straw from fields. This paper focuses on the effects of wheat and barley straw removal on SOC in irrigated production systems, and related the results to estimates of the minimum straw C inputs required to maintain SOC (MSC) from rain-fed systems. Six studies compared SOC changes with time in irrigated systems in which wheat straw was removed or retained. These studies indicated that SOC did not decline when residues were removed. Apparently belowground biomass is supplying C to irrigated soils at a rate sufficient to maintain SOC with time. However, under rain-fed systems, returning residue to the soil was required to maintain SOC. Estimates of MSC were obtained from nine rain-fed wheat system studies. Averaged across all rain-fed MSC values, 4.14 Mg more straw per ha was required to maintain SOC in rain-fed than in irrigated systems. Presently, the rain-fed based MSC values are the best information available to evaluating residue removal effects but caution should be used in applying these in irrigated systems. The results from this limited number of irrigated studies suggest that rain-fed estimates of MSC will overestimate the MSC in irrigated systems and underestimate the available irrigated straw resources. There is need to evaluate the effect of residue removal on SOC for diverse irrigated systems
Matrix-based fertilizers reduce nutrient leaching while maintaining Kentucky bluegrass growth
Get PDFAbstract We tested the efficacy of matrix-based
fertilizers (MBFs) to improve Kentucky bluegrass
(Poa pratensis L.) growth while reducing NH, NO3,
dissolved reactive phosphorus (DRP), and total
phosphorus (TP) compared to commercial slowrelease
fertilizer (SRF) Polyon®, ESN®, and Avail®
in greenhouse column studies. The MBFs covered a
range of inorganic N and P in compounds that are
relatively loosely bound (MBF6) and more tightly
bound compounds (MBF7) with Al(SO4)318H2O
and/or Fe2(SO4)33H2O and with high ionic exchange
compounds starch, cellulose, and lignin. The total
amount of NO3 and NH4 leached was greater from
columns receiving Polyon® and ESN® fertilizers than
all other treatments. The MBF6+Avail® or MBF7+
Avail® fertilizers leached 64–68% less NO3 than
Polyon® (43-0-0) and ESN® (46-0-0), and 73–76%
less TDP and TP than Avail® (10-34-0). A greater
amount of NO3 was leached from the MBF6+Avail®
and the MBF7+Avail® treatments than the other MBF
fertilizer treatments. Shoot and root biomass were
greater when plants received the Avail®, MBF6+
Avail®, and MBF7+Avail® fertilizer treatments than
the other fertilizer treatments. When combined with
small quantities of commercial SRFs, these new MBFs
were able to maintain plant growth while reducing N
and P leaching. These new MBF formulations do not
depend on organic or inorganic coatings to reduce N
and P leaching and with further testing and development
could be effective commercial fertilizers
Site-Specific Nematode Management for Potatoes in Idaho Using 1,3-Dichloropropene; Experiences and Economics
Get PDFFumigation for nematode management in irrigated potato production systems of Idaho is widely practiced. Spatially uniform fumigation with large scale soil injection equipment is the only labeled application method for 1,3-dichloropropene. Plant-parasitic nematode species exhibit spatially variable population densities that provide an opportunity to practice site-specific fumigation to reduce chemical usage and production costs. From 2002 through 2008, 62 commercial potato fields in eastern Idaho were field tested using geo-referenced grid soil sampling for plant-parasitic nematode population densities. In total, 4,030 grid samples were collected representing nearly 3200 ha of commercial potato production. Collectively, 73% of the grid samples had Columbia Root Knot (CRN) (Meloidogyne chitwoodi) densities below the detectable limit. Site-specific fumigation is the practice of varying application rate of fumigant based on nematode population density. Over the past 3 years, 1200 ha of potato production has been site-specific fumigated for CRN nematode control in eastern Idaho. On average this practice has resulted in a 30% reduction in chemical usage and production cost savings of 200/ha. Based on farm-gate receipts and USDA inspections provided by potato producers, potato tuber yield and quality have not been adversely affected using site-specific fumigation technology
Seed Treatments for the Control of Insects and Diseases in Sugarbeet
Get PDFInsect feeding and vectoring of viruses cause serious problems in sugarbeet production worldwide. In order to ameliorate insect and disease problems on sugarbeet, two seed treatments, Poncho Beta (60 g a.i. clothianidin + 8 g a.i. beta-cyfluthrin/100,000 seed) and Cruiser Tef (60 g a.i. thiamethoxam + 8 g a.i. tefluthrin/100,000 seed) were investigated (the neonicotinoid was tested alone in some trials). The two seed treatments and an untreated check were tested in a series of seven field trials from 2006 to 2008 along with various commercial sugarbeet cultivars in a randomized complete block design with eight replications per trial. Natural insect incidence and curly top symptoms were evaluated. Both Poncho and Cruiser provided significant reduction in curly top symptoms and incidence of spinach leafminer (Pegomya hyoscyami Panzer), black bean aphid (Aphis fabae Scopoli), and sugarbeet root aphid (Pemphigus betae Doane). At times Poncho performed better than Cruiser, but yield parameters for the two products were similar. When compared over six trials, the untreated check and Poncho Beta treatments averaged 74.5 and 81.7 t/ha, respectively. Neonicotinoid seed treatments will play an important role in disease and insect management in sugarbeet production, but should be viewed as a supplement to host resistance and not a substitute for it
Beet curly top resistance of released germplasm from the USDA-ARS Program at Fort Collins, CO, 2009
Get PDFSeventy sugar beet (Beta vulgaris L.) germplasms released from the USDA-ARS Breeding Program in Fort Collins, Colorado over the last 40 years and 27 experimental germplasm were screened for resistance to Beet severe curly top virus (BSCTV) in 2009. The curly top evaluation was conducted at the USDA-ARS North Farm in Kimberly, ID which had been in beans in 2008. The field was plowed in the fall, fertilized (75 lb N/A and 75 lb P2O5/A) on 22 Apr 09, sprayed with Ethotron (2 pt/A), and roller harrowed. The germplasm was planted (density of about 143,000 seeds/A) on 18 May. The plots were two rows 10 ft long with 22-in row spacing and arranged in a randomized complete block design with three replications. A resistant breeding line from Betaseed, Inc., G6040, was included as a resistant check. The fields were sprinkler irrigated and hand weeded as necessary. Plant populations were thinned to about 47,500 plants/A on 19 Jun. Plants were inoculated at the four to six leaf growth stage on 23 Jun with six viruliferous beet leafhoppers per plant. The beet leafhoppers were moved twice a day (right after sunrise and just before sunset) for one week by dragging a tarp through the field. The plants were sprayed with Lorsban 4E (1.5 pints/A) on 7 Jul to kill the beet leafhoppers. The plots were rated for foliar symptom development using a scale of 0-9 (0 = healthy and 9 = dead; Mumford 1974), with disease index (DI) treated as a continuous variable. Data were analyzed using the general linear models procedure (Proc GLM-SAS), and Fisher’s protected least significant difference was used for mean comparisons.
Disease development was uniform and severe. Other disease problems were not evident in the plot area. Only 14 germplasm (some of the FC600 series, FC403CMS, and some experimental germplasms) were not significantly different from G6040 (resistant control). Very little of the germplasm tested was selected specifically for resistance to beet curly top, except for FC600 lines. They were developed to combine resistance to BSCTV with resistance to Cercospora beticola. Nonetheless, it is important for germplasm to be screened against as many diseases as possible, because plant breeders want as much information for a germplasm as is available. Many of the germplasms under development were from a collaborative breeding project with the USDA-ARS sugar beet breeding program at Salinas, CA, and much of the germplasm from this source has good resistance to beet curly top. Two of the lines that did well were experimental hybrids in which the female parent (C790-15cms and C833-tcms) was a Salinas germplasm with good resistance to beet curly top. Some of the more recently released lines from the FC700 series also did well, although significantly worse than the resistant check. Both FC721 and FC723 were developed to combine resistance to Rhizoctonia root and crown rot with resistance to beet curly top, and both were significantly better than the worse performing germplasm (DI = 9.0). The FC400 lines, which did well, were released historically as parental lines for performance under Spanish growing conditions and both FC403CMS and FC401 did well
Airborne endotoxin concentrations at a large open-lot dairy in southern Idaho
Get PDFEndotoxins are derived from gram-negative bacteria and are
a potential respiratory health risk for animals and humans. To
determine the potential for endotoxin transport from a large
open-lot dairy, total airborne endotoxin concentrations were
determined at an upwind location (background) and five
downwind locations on three separate days. The downwind
locations were situated at of the edge of the lot, 200 and 1390
m downwind from the lot, and downwind from a manure
composting area and wastewater holding pond. When the
wind was predominantly from the west, the average endotoxin
concentration at the upwind location was 24 endotoxin units
(EU) m−3, whereas at the edge of the lot on the downwind side
it was 259 EU m−3. At 200 and 1390 m downwind from the
edge of the lot, the average endotoxin concentrations were
168 and 49 EU m−3, respectively. Average airborne endotoxin
concentrations downwind from the composting site (36 EU m−3)
and wastewater holding pond (89 EU m−3) and 1390 m from
the edge of the lot were not significantly different from the
upwind location. There were no significant correlations between
ambient weather data collected and endotoxin concentrations
over the experimental period. Th e downwind data show that
the airborne endotoxin concentrations decreased exponentially
with distance from the lot edge. Decreasing an individual’s
proximity to the dairy should lower their risk of airborne
endotoxin exposure and associated health effects