Productivity and Nutritive Quality of Johnsongrass ( Sorghum halepense

In the southeastern USA, there is an abundance of broiler litter from commercial poultry production that is available for use as fertilizer, but cropland and pastureland amended with broiler litter often exhibit greatly increased soil-test P. We evaluated productivity and nutritive quality of Johnsongrass (Sorghum halepense) that was interseeded with or without white clover (Trifolium repens) and which commercial fertilizer (ammonium nitrate and diammonium phosphate) or broiler litter was applied on the basis of soil-test P; broiler litter was supplemented with ammonium nitrate to be isonitrogenous with commercial fertilizer. Forage dry matter yield and foliar concentrations of crude protein, cell wall constituents, P, K, and Cu were not different among fertilizer treatments, and concentration of Zn was only slightly greater for forage amended with broiler litter than commercial fertilizer. Results indicate that broiler litter can be a cost-effective alternative to commercial fertilizer for warm-season forage production when applied on the basis of soil-test P

The Pleasures and Pitfalls of Interdisciplinary Research in Agriculture

Increasingly, interdisciplinary research is being touted as a way to solve real-life problems of interest to the taxpayers who support research at public universities. The purpose of this paper is to examine the benefits of interdisciplinary agricultural research involving economists and natural scientists, to discuss problems associated with carrying out this type of work and to offer some suggestions on how such research can be facilitated. Mutual trust and ongoing relationships can lead to better timing of collaboration and more satisfaction for all parties. Open communications are also important for success in collaboration. Within the border university environment, it is important for tenure and promotion committees to be able to properly evaluate interdisciplinary work; otherwise, faculty will not be properly rewarded for these efforts

The Pleasures and Pitfalls of Interdisciplinary Research in Agriculture

Increasingly, interdisciplinary research is being touted as a way to solve real-life problems of interest to the taxpayers who support research at public universities. The purpose of this paper is to examine the benefits of interdisciplinary agricultural research involving economists and natural scientists, to discuss problems associated with carrying out this type of work and to offer some suggestions on how such research can be facilitated. Mutual trust and ongoing relationships can lead to better timing of collaboration and more satisfaction for all parties. Open communications are also important for success in collaboration. Within the border university environment, it is important for tenure and promotion committees to be able to properly evaluate interdisciplinary work; otherwise, faculty will not be properly rewarded for these efforts.Interdisciplinary research, Agriculture, Economics, Agribusiness, Research and Development/Tech Change/Emerging Technologies,

Nutritive Quality of Highbush Blackberry (Rubus argutus) Exposed to Tropospheric Ozone

Numerous studies have examined the impacts of ground level O3 on plants that are important for human consumption, but native species that are important for wildlife have received less scrutiny. During May-August 2004 we examined the effects of O3 on biomass production and nutritive quality of highbush blackberry (Rubus argutus Link), an important forage for white-tailed deer (Odocoileus virginianus Zimmerman) and other herbivorous mammals. Plants were fumigated in open-top chambers with three levels of O3 in a randomized-block experiment with three replicates of each treatment. Our three experimental treatments were carbon-filtered air, characteristic of clean air quality; nonfiltered air, representative of air quality in Auburn, AL; and air with double (23) the ambient concentration of O3. Although biomass production was not influenced by O3 exposure, nutritive quality of plants was associated negatively with O3 concentration. Specifically, neutral detergent fiber was greater and relative feed value was less in plants exposed to elevated levels of O3. Similarly, in vitro dry matter digestibility tended to be less in plants exposed to elevated O3. Nutritive quality of regrowth vegetation followed a similar pattern, where neutral detergent fiber was greater and relative feed value was less in plants exposed to elevated levels of O3. These data suggest that elevated levels of ground level O3 could have implications for diet selection of herbivorous mammals. The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Nutritive Quality of Big Bluestem (Andropogon gerardii) and Eastern Gamagrass (Tripsacum dactyloides) Exposed to Tropospheric Ozone

Tropospheric ozone (O3) is a phytotoxic air pollutant widespread in industrialized nations of the world. Ozone is produced by the photo-oxidation of hydrocarbons released into the atmosphere by combustion of fossil fuels. Studies demonstrate O3 can be transported from metropolitan areas to rural areas important to agricultural and forestry practices. Reports regarding O3 effects have focused on vegetation important to food production or agronomic crops of economic importance. However, relatively little is known about O3 effects on native plant species. The effects of tropospheric O3 on two warm-season grasses, eastern gamagrass (Tripsacum dactyloides L.) and big bluestem (Andropogon gerardii Vitman), were examined during June-September of 2003. Plants were fumigated with three levels of O3 in a randomized-block experiment with three replicates of each treatment. Grasses were grown in open-top chambers with introduced carbon-filtered (CF) air, characteristic of clean air quality; non-filtered (NF) air, representative of quality in Auburn, AL; and air with double (2X) the ambient concentration of O3. Because forage quality can be as important as quantity, we determined various effects on nutritive quality characteristics in addition to biomass yield. Big bluestem exhibited little response to O3 exposure. For eastern gamagrass, we generally found decreased nutritive quality with increasing O3 exposure as evidenced by increased concentrations of cell wall constituents and decreased concentrations of N. Regrowth of both species exhibited little treatment effect which emphasizes the importance of timing and duration of O3 exposures in relation to physiological stage of plant development. Decreased nutritive quality parameters observed for eastern gamagrass may have implications to diet selection and nutrient intake by ruminant herbivores. In addition, range managers can use species-specific information regarding O3 sensitivity to make decisions about mechanical harvesting and grazing regimes of these forages growing in areas exposed to elevated O3 concentrations.  The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 2020Legacy DOIs that must be preserved: 10.2458/azu_jrm_v59i3_lewi

Author's personal copy Digestive utilization of ozone-exposed forage by rabbits (Oryctolagus cuniculus)

a b s t r a c t A mixture of common Southern Piedmont (USA) grassland species (Lolium arundinacea, Paspalum dilatatum, Cynodon dactylon and Trifolium repens) was exposed to O 3 [ambient (non-filtered; NF) and twice-ambient (2X) concentrations] and fed to individually caged New Zealand white rabbits (Oryctolagus cuniculus) in a digestibility experiment. Forages and feed refusals were analyzed for concentrations of total cell wall constituents, lignin, crude protein, and soluble and hydrolyzable phenolic fractions. Neutral detergent fiber and acid detergent fiber digestibility by rabbits were significantly lower for 2X than NF forage. Decreased digestibility could not be attributed to lignin concentrations, but was associated with increased concentrations of acid-hydrolyzable and saponifiable phenolics. Exposure of forage to elevated O 3 resulted in decreased digestible dry matter intake by rabbits. Elevated O 3 concentrations could be expected to have a negative impact on forage quality, resulting in decreased nutrient utilization by mammalian herbivores in Southern Piedmont grasslands under projected future climate scenarios