Aluminum-tolerant wheat (Triticum aestivum L.) cultivars are often employed to damper the yield-limiting impacts of Al toxicity in acidic soils. Tolerance is often facilitated by the Al-activated malate transporter 1 (ALMT1) gene, which increases anion permeability of wheat roots and exudes malate in the presence of Al. However, few studies have explored the phenotypic incongruities of closely related genotypes with ALMT1(+) or without ALMT1(−). A field study initiated in Stillwater, OK, on an Easpur loam (fine-loamy, mixed, superactive, thermic Fluventic Haplustolls) was established to determine the Al tolerance of eight related winter wheat cultivars chosen for presence or absence of ALMT1 [Duster (+), Lonerider (+), OK14319 (+), Jagger (+), Iba (−), Gallagher (−), Spirit Rider (−), Smith's Gold (−)]. Significant differences were found among cultivars in their forage yield responses to Al concentration and soil acidity. Duster (first), Spirit Rider (second), and Gallagher (third) were the most acid tolerant and consistent in forage yield across study years. However, no such trend was observed in the grain yields of any of the cultivars, as there was no clear semblance of acid tolerance in grain yields between study years. Despite the similarity of genetic backgrounds, forage and grain yield productivity of cultivars in this study varied between years and was not wholly dependent on the presence or absence of the ALMT1 gene. Nevertheless, the utilization of acid-tolerant winter wheat cultivars has the potential to significantly reduce forage yield loss under acidic soil conditions with high Al concentrations. 1 INTRODUCTION Wheat (Triticum aestivum L.

Knowing the nutrient contents of animal manure is important in nutrient management plan development. Nutrient contents of manure may have been changed over time due to improvement of breeding, feeding, and manure handling. Therefore, the major characteristics of beef feedlot manure, dairy manure, poultry litter, and swine effluent were summarized using the data from two service laboratories in Kansas and Oklahoma. In general, dry matter contents, pH, and macro-and micronutrient contents of the manures had little changes over time in the last 5 to 20 yr. Only a trend of phosphorus decrease over time in swine effluent was observed. The nutrient contents of various manures largely depend on the dry matter contents. The nitrogen (N), phosphorus (P) and potassium (K) contents are in the following order: broiler litter > beef feedlot manure > dairy manure > swine effluent. Various environmental regulations related to animal manure management have been established and implemented in most parts of the world. The awareness of sustainable manure application to cropland has greatly improved in the last twenty years. More efforts need to be made to further improve nutrient use efficiency of animal manure, protect soil health, and environmental quality.

Intensive cultivation and unprecedented utilization of ammoniacal fertilizer has accelerated soil acidification in the southern Great Plains and many other parts of the world. During a two-year study that evaluated the impact of soil pH and aluminum (Al) toxicity on winter wheat yield potential, we observed a variance in the edaphic responses of the two study sites (Stillwater and Chickasha) to two soil amendments, Alum [Al2(SO4)3] and lime [Ca(OH)2]. We found that AlKCl values at Stillwater were 223% and 150% higher than Chickasha during Year 1 and Year 2, respectively, with similar soil pH. Additionally, Alsat values at Stillwater were 30.6% and 24.9% higher than Chickasha during Year 1 and Year 2, respectively. Surprisingly, when treated as a bivariate of Alsat, soil buffer indices differed in graphical structure. While Chickasha was identified with a cubic polynomial (p < 0.0001), Stillwater was characterized by linear regression (p < 0.0001). We have reason to believe that this divergence in edaphic response might be attributed to the organically bound Al, dissolved organic carbon (DOC), spatio-temporal variance, and adsorption reactions regulated by the solubility of Al(OH)+2 species in acidic soils.

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By mixing and potentially aerating dung, dung beetles may affect the microbes producing the greenhouse gases (GHGs): carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Here, their sum-total global warming effect is described as the carbon dioxide equivalent (CO2e). Our literature analysis of reported GHG emissions and statistics suggests that most dung beetles do not, however, reduce CO2e even if they do affect individual GHGs. Here, we compare the GHG signature of homogenized (“premixed”) and unhomogenized (“unmixed”) dung with and without dung beetles to test whether mixing and burial influence GHGs. Mixing by hand or by dung beetles did not reduce any GHG – in fact, tunneling dung beetles increased N2O medians by ≥1.8x compared with dung-only. This suggests that either: 1) dung beetles do not meaningfully mitigate GHGs as a whole; 2) dung beetle burial activity affects GHGs more than mixing alone; or 3) greater dung beetle abundance and activity is required to produce an effect.