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Kimberly sugar beet germplasm evaluated for rhizomania and storage rot resistance in Idaho, 2015.
Get PDFRhizomania caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious sugar beet production problems. To identify sugar beet germplasm lines with resistance to BNYVV and storage rots, 11germplasm lines from the USDA-ARS Kimberly sugar beet program were screened. The lines were grown in a sugar beet field infested with BNYVV and one treated with Telone II (18 gpa) in Kimberly, ID during the 2015 growing season in a randomized complete block design with 4 replications. At harvest on 7 October 2015, roots were dug and evaluated for symptoms of rhizomania and also placed in an indoor commercial sugar beet storage building. After 126 days in storage, samples were evaluated for surface fungal growth. Roots for entries from the RZ field averaged 11% of the root surface covered by fungal growth while those from the Telone field averaged 60%. Why these preliminary data suggest a Telone II application would lead to more fungal in storage is unknown. Entry K19-17 was found to have both good BNYVV resistance and only 2% fungal growth on roots from the RZ field. Given the wide ranging responses, selecting germplasm for rhizomania resistance and combining this resistance to storage rots will lead to considerable economic benefit for the sugar beet industry
Ft. Collins sugar beet germplasm evaluated for rhizomania and storage rot resistance in Idaho, 2015
Get PDFFifty-seven sugar beet (Beta vulgaris L.) lines from the USDA-ARS Ft. Collins sugar beet program and four check cultivars were screened for resistance to Beet necrotic yellow vein virus (BNYVV), the causal agent of rhizomania, and storage rot. The rhizomania evaluation was conducted at the USDA-ARS North Farm in Kimberly, ID. Seed of the sugar beet germplasm lines was planted on April 21. One-row plots, 10 ft long with 22-in row spacing between rows were arranged in a randomized complete block design with 4 replications. The trial relied on natural infection for rhizomania and storage rot development. The plots were rated for foliar symptom (percentage of plants with yellow, stunted, upright leaves) development on July 8 and 20. At harvest, roots in the plots were rated for symptom development using a scale of 0 to 9 (0 = healthy and 9 = dead). At harvest, eight roots per plot were also collected in a mesh-onion bag and placed in an indoor commercial storage facility in Paul, ID on October 8. Following 126 days in storage, the roots were evaluated for the percentage of root surface area covered by fungal growth. Data were analyzed using the general linear models procedure, and Fisher’s protected least significant difference (a = 0.05) was used for mean comparisons. Rhizomania symptom development was uniform and other disease problems were not evident in the plot area. The BNYVV susceptible check had 89 to 92% foliar symptoms and a high root disease severity rating. The three BNYVV resistant checks (2, 3, and 4) had no foliar symptoms and low root ratings. Most entries had fewer foliar symptoms and a better root rating than the susceptible check indicating they have some level of resistance. Based on BNYVV root ratings, the entries not significantly different from the best performing entry (25) were checks (2, 3, 4), and entries 16, 20, 34, and 48). All of these had foliar ratings that were 4% 4% or less (not significantly different from the best performing entries with 0%). Entries 25, 16, and 20 were experimental hybrids with FC1740 (entry 48 – Rz1Rz1Rz2Rz2, based on associated SNP markers) or FC1741 (entry 49 – rz1rz1Rz2Rz2, based on associated SNP markers). Entry 34 is a polycross population developed for resistance to root rot complexes. Storability is an important trait in harvested beet roots and beets were screened for surface rotting. The primary fungal growth was an Athelia-like Basidiomycete, but Botrytis sp. and Penicillium sp. were also frequently present. Entries 9, 11, 18, 31, 34, and 43 were not significantly different from the entry most resistant to fungal growth in storage (entry 18 with only 2%). Entries 14, 20, 21, 48, and 53 performed well for all variables. Some of these entries may serve as a starting point for identifying additional sources of resistance to both BNYVV and storage rots
Impact of the intensification of beef production in Brazil on greenhouse gas emissions
Get PDFThe objective of this study was to investigate the impact of increasing pasture productivity using fertilizers, forage legumes, supplements and concentrates, on the emissions of greenhouse gases (GHGs) in five scenarios for beef production with Nellore
cattle in the Cerrado region of Brazil. A life cycle analysis (LCA) approach, from birth of calves to mature animals ready for slaughter at the farm gate, was utilized using both the Tier 1 and Tier 2 methodologies of the Intergovernmental Panel on Climate Change and the results were expressed in carbon dioxide equivalents per kg of carcass produced. The first four scenarios were based solely on cattle production on pasture, ranging from degraded Brachiaria pastures with minimal management, through to a mixed legume/Brachiaria pasture reformed every five years with P and K fertilizers and lime and an improved N fertilized (150 kg N/ha per year) pasture of Guinea grass (Panicum maximum). The most intensive scenario was also based on a fertilized Guinea grass pasture but with a 75 day finishing period in confinement with total mixed ration. To compare scenarios a herd based on 400 cows was utilized. Across the scenarios from 1 to 5 the increase in digestibility promoted a reduction in the forage intake for animal weight gain and a concomitant reduction in methane emissions per herd. For the estimation of nitrous oxide emissions from animal excreta using Tier 2, emission factors from a study in the Cerrado region were utilized which postulated lower emission from dung than from urine and much lower emissions in the long dry season in this region. Fossil carbon dioxide emissions from direct use of fuel and energy were also included in the LCA along with that necessary for the production of fertilizers, supplements and feeds. The greatest impact of intensification of the beef production systems was in the reduction of the area necessary for carcass production from 320 to 45 square meters per kg carcass. Carcass production increased from 43 to 65 Mg per herd across the scenarios from 1 to 5, and total emissions per kg carcass were estimated by Tier 2 methodology to be reduced from 53.7 to 27.9 kg carbon dioxide equivalents. GHG emissions per kg carcass were slightly lower for the mixed grass legume scenario (3), although this was partly due to the lack of data on emissions of nitrous oxide from legume residues. Another large source of uncertainty for the confection of such LCAs was the lack of data for enteric methane emissions from cattle grazing tropical forages
Sugarbeet yield and quality when substituting compost or manure for conventional nitrogen fertilizer
Get PDFTo profitably produce sugarbeet (Beta vulgaris L.) by maximizing recoverable sucrose, producers must effectively manage added nitrogen (N), whether it be from inorganic sources such as urea or from often readily available and sometimes less expensive organic sources such as manure or composted manure. Our multi-site study’s objective was to determine if equivalent sugarbeet root and sucrose yields could be achieved when substituting composted dairy cattle manure or stockpiled manure for conventional N (urea) fertilizer. Treatments at Site 1 (Parma, ID), for 2 y included a control (no N applied), urea (202 kg N/ha), compost (1089 and 2175 kg total N/ha), and manure (350 and 701 kg total N/ha). Treatments at Site 2 (Kimberly, ID), were a control, urea (82 kg N/ha), compost (403 and 913 kg total N/ha), and manure (433 and 850 kg total N/ha). Compost and manure were applied, then incorporated into two silt loams, a Greenleaf (Xeric Calciargid) at Parma in fall 2002 and 2003 and a Portneuf (Durinodic Xeric Haplocalcid) at Kimberly in fall 2002. Sugarbeet was planted the following spring. Site 1’s sugarbeet sucrose yields, averaged across years and organic N source rates, were 12.24 Mg/ha for urea, 11.88 Mg/ha for compost, and 11.20 Mg/ha for manure, all statistically equivalent. Corresponding one-year sucrose yields, still equivalent, were ca. 44% less at Site 2 than 1. Doubling the organic N application rates at Site 1 increased sugarbeet root yields by 15 to 26% and sucrose yields by 12 to 21%. Applying organic amendments in place of urea affected neither root nor sucrose yields but at one location decreased sugarbeet crop quality by increasing brei nitrate and conductivity, though without hindering sucrose recovery. Sugarbeet producers can use either compost or manure to satisfy their crop’s N needs without sacrificing sucrose yield
Biochar elemental composition and factors influencing nutrient retention
Get PDFBiochar is the carbonaceous solid byproduct of the thermochemical conversion of a carbon-bearing organic material, commonly high in cellulose, hemicelluloses, or lignin content, for the purposes of carbon sequestration and storage. More specifically, the thermal conversion process known as pyrolysis occurs when carbon-containing substances are introduced to elevated temperatures in the absence of oxygen at varying residence times, yielding biochar.
Several pyrolysis techniques employed to produce biochar differ in the temperature of reaction and residence time in the reactor. Different reactor residence times are described as slow (hours to days), fast (seconds to minutes), and flash (seconds). Fast or flash pyrolysis typically occurs around 500oC with residence times less than 500 milliseconds to 1 second and produces relatively greater gas yields with a concomitant decrease in biochar yield (~ 12%). Slow pyrolysis temperatures have ranged from 350 to 750oC but with residence times ranging from minutes to days. Slow pyrolysis yields a greater quantity of biochar (between 25 to 35%).
Pyrolysis temperature and type may be varied to maximize the desired biochar end-product. In general, increasing pyrolysis temperature tends to increase biochar total carbon, potassium, and magnesium content, pH, and surface area, and decrease cation exchange capacity. Slow pyrolysis, in general, tends to produce biochars with greater nitrogen, sulfur, available phosphorus, calcium, magnesium, surface area, and cation exchange capacity as compared to fast pyrolysis.
In addition to altering temperature and time, the importance of feedstock source needs to be recognized when utilizing biochar in situations such as a soil conditioner. Over the last 10 years biochar research and use has expanded exponentially and so have the feedstocks utilized. Biochars have now been created from corn, wheat, barley and rice straw, switchgrass, peanut, pecan, and hazelnut shells, sugarcane bagasse, coconut coir, food waste, hardwood and softwood species, poultry and turkey litter, swine, dairy, and cattle manure, and biosolids to name a few. Feedstock source influences end-product characteristics, and in general most plant-based biochars containing elevated carbon content and lesser quantities of necessary plant nutrients as compared to manure-based biochars.
It has been demonstrated that the mineral content of the feedstock has a significant effect on product distribution, with higher amounts of chloride salts reducing the amount of the solid biochar product. In addition, chloride and other inorganic salts also impact the chemical composition of the liquid, gas, and char pyrolysis products, potentially producing products with higher economic values. Existing studies indicate that even the trace amounts of minerals present in the various biomass sources and feedstock mixtures do have an impact on the chemical compositions of the products. Furthermore, both temperature and residence time, along with feedstock source or mixtures of sources, affect end-product characteristics
Water temperature in irrigation return flow from the Upper Snake Rock watershed
Get PDFWater returning to a river from an irrigated watershed could increase the water temperature in the river. The objective of this study was to compare the temperature of irrigation return flow water with the temperature of the diverted irrigation water. Water temperature was measured weekly in the main irrigation canal, 24 return flow streams and one ephemeral stream from 2005 to 2008 in the Upper Snake Rock (USR) watershed. The USR is an 82,000 ha watershed in southern Idaho, USA with about 60% of the area surface irrigated and the remaining area sprinkler irrigated. Median annual water temperatures in irrigation return flow streams were not greater than the water diverted from the river, suggesting that water flowing through the canal system and furrow irrigated fields does increase temperature. Water in seven of the 14 return flow streams that received flow from subsurface drains had significantly lower temperatures than the main canal in at least two years of the four years. Significant differences were generally only two to three degrees Celsius. Results of this study indicate that water can be diverted from a river for surface irrigation without increasing the temperature of the irrigation return flow
Stabilizing effect of biochar on soil extracellular enzymes after a denaturing stress
Get PDFStabilization of extracellular enzymes may maintain enzymatic activity for ecosystem services such as carbon sequestration, nutrient cycling, and bioremediation, while protecting enzymes from proteolysis and denaturation. A laboratory incubation study was conducted to determine whether a fast pyrolysis biochar (CQuest) derived from oak and hickory hardwood would stabilize extracellular enzymes in soil and prohibit the loss of potential enzyme activity following a denaturing stress, in this case microwaving. Soil was incubated in the presence of biochar (0, 1, 2, 5, or 10% by weight) for 36 days and subsequently exposed to microwave energies of 0, 400, 800, 1600, or 3200 Joules per gram of soil. Soil enzymes (ß-glucosidase, ß-D-cellobiosidase, N-acetyl-ß-glucosaminidase, phosphatase, leucine aminopeptidase, and ß-xylosidase) were analyzed by fluorescence-based assays. Biochar amendment significantly reduced the potential activity of leucine aminopeptidase and ß-xylosidase after the incubation period and prior to stress exposure. Microwaving provided stress through heat and loss of soil water, although at the lowest stress level (400 Joules per gram of soil) soil water loss was significantly reduced in soil amended with 10% biochar. Enzyme stabilization was demonstrated for ß-xylosidase, whereby intermediate biochar application rates (1 and 5 %) prevented a complete loss of this enzyme’s potential activity after soil was exposed to 400 (1% biochar treatment) or 1600 (5% biochar treatment) Joules of microwave energy per gram of soil. Potential activities of ß-glucosidase, ß-D-cellobiosidase, N-acetyl-ß-glucosaminidase, and phosphatase enzymes were not affected by biochar, and activities of these enzymes decreased significantly with increasing levels of microwave energy. We concluded that biochar has the potential to prevent evaporative losses of soil water to some degree and stabilize certain extracellular enzymes such as ß-xylosidase so that activity is maintained after a denaturing stress. This effect was dependent, however on biochar application rate and the enzyme itself. Furthermore, while biochar may reduce the potential activity of certain extracellular enzymes in soil, this phenomenon was not universal as the majority of enzymes assayed in this study were unaffected by exposure to biochar
Commercial sugar beet cultivars evaluated for rhizomania resistance and storability in Idaho, 2014
Get PDFRhizomania caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious sugar beet production problems. To identify sugar beet cultivars with resistance to BNYVV and evaluate storability, 33 commercial cultivars were screened by growing them in a sugar beet field infested with BNYVV in Kimberly, ID during the 2014 growing season in a randomized complete block design with 6 replications. At harvest on 24-25 September 2014, roots were dug and evaluated for symptoms of rhizomania and also placed in an indoor commercial sugar beet storage building. After 138 days in storage, samples were evaluated for surface rot, weight loss, and sucrose loss. Surface root rot ranged from 7 to 82%, weight loss ranged from 9.4 to 19.1%, sucrose losses ranged from 23 to 85%, and estimated recoverable sucrose ranged from 931 to 8,798 lb/A. Given these response ranges, selecting cultivars for rhizomania resistance and combining this resistance with storability will lead to considerable economic benefit for the sugar beet industry
Detection of purple sulfur bacteria in purple and non-purple dairy wastewaters
Get PDFPurple sulfur bacteria (PSB) in livestock wastewaters use reduced sulfur compounds and simple volatile organics as growth factors. As a result, the presence of PSB in manure storage ponds or lagoons is often associated with reduced odors. In this study, our objectives were to use molecular- and culture-based techniques to evaluate the occurrence of PSB in eight dairy wastewater ponds and identify physiochemical properties that might cause blooms to occur. Community DNA was extracted from composited wastewater samples, then the PufM gene and a conservative sequence for Chromatiaceae were amplified. Analysis of the 16S rRNA genes from denaturing gradient gel electrophoresis (DGGE) bands indicated that all of the dairy wastewater ponds contained sequences that matched with Thiocapsa roseopersicina, with sequences from a few ponds also matching with Marichromatium sp., Thiolamprovum pedioforme, and Thiobaca trueperi. PufM sequences amplified from pure and enrichment cultures were most similar to T. roseopersicina, indicating that it may be the dominant PSB in all wastewaters investigated. Purple wastewater ponds were also found to have the highest salinity, nitrogen, total and volatile solids, and chemical oxygen demand, suggesting that these factors might enhance PSB blooms. While not all ponds were phototrophic as determined visually and via a carotenoid assay, PSB could be enriched from the wastewaters, thus finding methods to enhance their growth in non-purple ponds should be investigated further
Beet curly top resistance in germplasm from the USDA-ARS Ft. Collins program, 2014
Get PDFNinety-seven sugar beet (Beta vulgaris L.) germplasm lines from the USDA-ARS Ft. Collins sugar beet program, a resistant control germplasm (1996A008), and three commercial control cultivars [SV2012RR (susceptible), Monohikari (susceptible) and HM PM90 (resistant)] were screened for response to Beet curly top virus (BCTV). The curly top evaluation was conducted at the USDA-ARS North Farm in Kimberly, ID. The plots were two rows 10 ft long with 22-in row spacing and arranged in a randomized complete block design with four replicates. Plants were inoculated at the four- to six-leaf growth stage with approximately six viruliferous beet leafhoppers per plant. The beet leafhoppers were redistributed three times a day during the first two days and then twice a day for five more days by dragging a tarp through the field. Plots were rated for foliar symptom development on 16 Jul using a scale of 0 to 9 (0 = healthy and 9 = dead). Data were analyzed in SAS using the general linear models procedure (Proc GLM), and Fisher’s protected least significant difference (LSD; a = 0.05) was used for mean comparisons. Curly top symptom development was uniform and no other disease problems were evident in the plot area. In total, four lines were not significantly different from the resistant control performance (HM PM90 with DI = 4.09), while six other lines, did not differ significantly from HM PM90 with a DI of 4.47. The lines will be investigated further to see if they represent novel sources of curly top resistance, and brought forward for release as curly top resistant germplasms. Identifying novel sources of resistance should allow seed companies to improve resistance to BCTV in commercial sugar beet cultivars. These results and germplasm will be accessible to interested parties through the USDA-ARS, NPGS GRIN database (http://www.ars-grin.gov/npgs/index.html)