Effects of Photoperiod, Low Temperature and N Nutrition on VSP Accumulation in Taproot of Alfalfa

In Medicago sativa L., vegetative storage protein (VSP), specifically accumulated in taproot, are strongly involved in nitrogen storage. How the accumulation of such VSPs is regulated remains largely unknown. Experiments were designed with non-nodulated alfalfa to determine if length of the photoperiod, a decrease of temperature, or high availability of mineral nitrogen may induce the accumulation of VSPs. 15N labelling was used to quantify nitrogen uptake and its further relative translocation within the plant while VSPs accumulation was analysed by ELISA quantification. Results showed that environmental factors such as shortening daylength or low temperature changed biomass allocation within the plant by reducing shoot growth. As a consequence, short days promoted the relative N allocation to taproot whereas VSP accumulation showed a higher trend. On the other hand, low temperature, changes in N source or availability in the nutrient solution, may lead to a higher influx of nitrogen and a higher soluble protein relative concentration in taproot while VSP abundance remained low

Root Nitrogen Cycling and Alfalfa Stress Tolerance

Our hypothesis is that certain root N pools are utilized preferentially during the early shoot regrowth. Our objective was to determine the relative contribution of crown N, root N, and specific root N pools to shoot regrowth after defoliation. We used 15N to follow N into and out of crowns, roots, and specific root N pools, to regrowing shoots after defoliation. The low molecular weight N pool (amino acids, inorganic N,...) acquired 15N rapidly within 2 d of N application. Movement of 15N into the protein-N and insoluble-N pools was delayed initially, but continued until 8 d after N application. Defoliation 30 d after 15N application resulted in N transfer from roots and crowns to regrowing shoots. All root N pools lost 15N label initially after defoliation, with a more extensive decline occurring for the protein-N and low molecular weight-N pools

Improvement of Lucerne Cutting Management: The Relative Impact of Initial Organic Reserves, Cutting Height and Residual Leaf Area on Forage Yield

Less lucerne (Medicago sativa L.) is now grown because of difficulties arising from 2 interacting characteristics: productivity and stand persistence. Optimisation of these two parameters depends highly of the cutting management (cutting height and/or frequency) and of the taproot N reserves. For example, Avice et al. (1997) showed that lucerne shoot regrowth is relates closely to taproot soluble protein concentrations (especially vegetative storage protein: VSP). However, it is not known how stubble C-N reserves and/or residual leaf area (both depending of the cutting management) influence the contribution of taproot reserve-derived C-N supply to regrowing lucerne shoots after defoliation. This study aimed to estimate the role of stubble C/N reserves or residual leaf area (RLA) on the contribution of taproot N reserves to shoot regrowth of lucerne after cutting

Agricultural Impacts of Climate Change in Indiana and Potential Adaptations

While all sectors of the economy can be impacted by climate variability and change, the agricultural sector is arguably the most tightly coupled to climate where changes in precipitation and temperature directly control plant growth and yield, as well as livestock production. This paper analyzes the direct and cascading effects of temperature, precipitation, and carbon dioxide (CO2) on agronomic and horticultural crops, and livestock production in Indiana through 2100. Due to increased frequency of drought and heat stress, models predict that the yield of contemporary corn and soybean varieties will decline by 8–21% relative to yield potential, without considering CO2 enhancement, which may offset soybean losses. These losses could be partially compensated by adaptation measures such as changes in cropping systems, planting date, crop genetics, soil health, and providing additional water through supplemental irrigation or drainage management. Changes in winter conditions will pose a threat to some perennial crops, including tree and fruit crops, while shifts in the USDA Hardiness Zone will expand the area suitable for some fruits. Heat stress poses a major challenge to livestock production, with decreased feed intake expected with temperatures exceeding 29 °C over 100 days per year by the end of the century. Overall, continued production of commodity crops, horticultural crops, and livestock in Indiana is expected to continue with adaptations in management practice, cultivar or species composition, or crop rotation

Indiana’s Agriculture in a Changing Climate: A Report from the Indiana Climate Change Impacts Assessment

Indiana has long been one of the nation’s leaders in agricultural productivity. Favorable temperatures and precipitation help Indiana farmers generate over $31 billion worth of sales per year, making the state 11th in total agricultural products sold. Changes to the state’s climate over the coming decades, including increasing temperatures, changes in precipitation amounts and patterns, and rising levels of carbon dioxide (CO2) in the air will result in several direct and indirect impacts to the state’s agricultural industry. This report from the Indiana Climate Change Impacts Assessment (IN CCIA) describes how projected changes in the state’s climate will affect the health of livestock and poultry, growing season conditions for crops, the types of crops that can be planted, soil health and water quality as well as weed, pest and disease pressure for agricultural production statewide

Minimum Dataset and Metadata Guidelines for Soil-test Correlation and Calibration Research

Soil-test correlation and calibration data are essential to modern agriculture, and their continued relevance is underscored by the expansion of precision farming and the persistence of sustainable soil management priorities. In support of transparent, science-based fertilizer recommendations, we seek to establish a core set of required and recommended information for soil-test P and K correlation and calibration studies, a minimum dataset, building on previous research. The Fertilizer Recommendation Support Tool (FRST) project team and collaborators are developing a national database that will support a soil-test-based nutrient management decision aid tool. The FRST team includes over 80 scientists from 37 land-grant universities, two state universities, one private university, three federal agencies, two private not-for-profit organizations, and one state department of agriculture. The minimum dataset committee developed and vetted a robust set of factors fo minimum dataset consideration that includes information on soil sample collection and processing, soil chemical and physical properties, experimental design and statistical analyses, and metadata about the trial, production system, and field management. The minimum dataset provides guidelines for essential information to meet the primary objective of knowledge synthesis, including meta-analysis and systemic reviews, but permits researchers the flexibility to satisfy local, state, and regional objectives. Ultimately, this consensus-driven effort seeks to establish a standard that ensures the maximum utility and impact of modern correlation and calibration studies for developing crop nutrition recommendations that improve productivity and profitability for the crop producer, while reducing environmental impacts of nutrient losses

July 2004 Report of Progress

Progress of each ALS-NSCORT project given by each project lead. 10 pages

Field trial guidelines for evaluating enhanced efficiency fertilizers

There are many fertilizer additives and alternatives that aim to increase plant nutrient use efficiency and reduce nutrient losses to the environment, here referred to collectively as enhanced efficiency fertilizers (EEFs). However, there is often insufficient published scientific field trial results across a variety of locations, climates, soils, cropping systems, and management scenarios to prove their efficacy and conditions for use. Guidelines for common minimum datasets and data stewardship in evaluating the agronomic performance and environmental impact of EEFs are needed for researchers to follow. Such guidelines will improve hypothesis testing centered on product efficacy and provide producers with guidance on how these technologies function and perform when integrated with other management practices within the 4R Nutrient Stewardship Framework. A scientific committee was formed to develop a set of protocol guidelines for evaluating EEFs in replicated, plot-based field trials on an international scale. The guidelines are composed of experimental design and core metadata, crop and soil analyses, environmental loss measurements, and data stewardship, and include both recommended and required components to allow for flexibility and adaptability depending on the trial location, objectives, infrastructure capacity, product type, and depth of understanding of the potential EEF efficacy. This approach will ensure consistency and compatibility in experimental design and data collection to support data integration, analysis, and reuse leading to large-scale impact and end-user confidence