Agronomy and Crop Sciences Commons^™

Grazing Management For Alfalfa Persistence And Productivity In Warm-Climate Regions, D. Basigalup

IGC Proceedings (1977-2023)

Alfalfa is the most important cultivated forage crop in Argentina, where about 3 million hectares are grown. Even though the use of direct grazing is coming down during the last 15 years, it is still important for both beef and dairy production. Alfalfa grazing can play an important role in reducing operative costs and decreasing quality loss due to forage conservation (hay or silage). In this paper, the main concepts necessary to implement adequate and practical rotational grazing systems are briefly discussed. Particular attention is given to issues such as grazing frequency, grazing period, pasture use efficiency, and alfalfa quality …

Genetic Improvement Of Bermudagrass For Hay Producers, W. F. Anderson, L. Baxter, R. N. Gates, E. Rios

IGC Proceedings (1977-2023)

Bermudagrass (Cynodon spp.) is considered the most valuable warm-season perennial grass for hay producers in the Southeastern United States. Bermudagrass genotypes have overall good forage quality, high yields, and store well. However, there are challenges to producing good hay for the market. First, early green-up in the spring is needed to allow for four to five productive clippings during the summer. When first establishing production fields, quick emergence and cover are important for reducing weeds. Forage bermudagrass is somewhat tolerant to drought, however, low rainfall substantially reduces yields. If rainfall is too abundant, it is difficult to have timely …

Genetic Variability Of Lucerne Landraces From Central Italy Detected By Rapd Markers, L Russi, G Barcaccia, M Falcinelli, F Veronesi

IGC Proceedings (1977-2023)

With the aim to characterize six lucerne landraces (Medicago sativa L.), representing a sample of a collection from central Italy, sixty individuals per landrace were evaluated by screening for RAPD markers with three lucerne-specific primers. Twenty-one amplification products were scored as present or absent across all plants. The dendrogram from mean genetic similarity estimates displayed Casalina alone and the other landraces clustered into one distinct group, showing a single branch point with more than 73% of genetic similarity. The discriminant analysis grouped the landraces in a similar manner. The first function maximally separated the group Grosseto, Gubbio and C. …

Amphicarpic Legumes For Tropical Pasture Persistence, R Schultze-Kraft, A Schmidt, H Hohn

IGC Proceedings (1977-2023)

Amphicarpy, by which a plant produces underground seeds in addition to aerial fruits, is found in many plant families and in species of at least 15 legume genera. First studies on the tropical Centrosema rotundifolium and subtropical Macroptilium panduratum revealed for both species, besides their stoloniferous growth habit, two important mechanisms for survival under unfavorable conditions: (1) Underground meristems and reserve organs, and (2) regeneration from a soil seed reserve based on underground, aerial-flowering independent, seed production. Underground seed production was for both species particularly high on very sandy soils, but amphicarpy enables the plants to exhibit a plasticity response …

Filling The Agronomic Data Gap Through A Minimum Data Collection Approach, Fatima A. Tenorio, Juan I. Rattalino Edreira, Juan Pablo Monzon, Fernando Aramburu-Merlos, Achim Dobermann, Armelle Gruere, Juan Martin Brihet, Sofia Gayo, Shawn Conley, Spyridon Mourtzinis, Nester Mashingaidze, Alex Sananka, Stephen Aston, Jonathan J. Ojeda, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Context: Agronomic data such as applied inputs, management practices, and crop yields are needed for assessing productivity, nutrient balances, resource use efficiency, as well as other aspects of environmental and economic performance of cropping systems. In many instances, however, these data are only available at a coarse level of aggregation or simply do not exist.

Objectives: Here we developed an approach that identifies sites for agronomic data collection for a given crop and country, seeking a balance between minimizing data collection efforts and proper representation of the main crop producing areas.

Methods: The developed approach followed a …

High Target Homology Does Not Guarantee Inhibition: Aminothiazoles Emerge As Inhibitors Of Plasmodium Falciparum, Sandra Johannsen, Robin M. Gierse, Arne KrüGer, Rachel L. Edwards, Vittoria Nanna, Anna Fontana, Di Zhu, Tiziana Masini, Lais Pessanha De Carvalho, Mael Poizat, Bart Kieftenbelt, Dana M. Hodge, Sophie University Of Nebraska-Lincoln,, Daan Bunt, Antoine Lacour, Atanaz Shams, Kamila Anna Meissner, Edmarcia Elisa De Souza, Melloney Dröge, Bernard Van Vliet, Jack Den Hartog, Michael C. Hutter, Jana Held, Audrey R. Odom John, Carsten Wrenger, Anna K.H. Hirsch

Department of Agronomy and Horticulture: Faculty Publications

In this study, we identified three novel compound classes with potent activity against Plasmodium falciparum, the most dangerous human malarial parasite. Resistance of this pathogen to known drugs is increasing, and compounds with different modes of action are urgently needed. One promising drug target is the enzyme 1-deoxy-D-xylulose-5- phosphate synthase (DXPS) of the methylerythritol 4-phosphate (MEP) pathway for which we have previously identified three active compound classes against Mycobacterium tuberculosis. The close structural similarities of the active sites of the DXPS enzymes of P. falciparum and M. tuberculosis prompted investigation of their antiparasitic action, all classes …

Impact Of Type Of K Fertilizer On Dcad Of Fen Grassland In Northeast Germany, A. Behrendt, J. Pickert, F. Eulenstein, B. Kroschewski

IGC Proceedings (1977-2023)

A lower DCAD is required in the diet fed during the prepartum period, but increasing the DCAD of diets fed during lactation increased milk yield and dry matter intake (Overton 2020). We conducted 3 cutting date/type of fertilizer trials, harvested with 5, 4 and 3 cuts per year over 3 years. Compared to the chloride based K fertilizer, the application of a sulphate based K fertilizer did not change dry matter yield and fodder quality (NEL-, XP-content) but led to significant higher DCAD in the grass in cut 1 - 3 of all trials over 3 years. The increase of …

The Business Case For Healthy Grasslands-Based Agriculture – Economic And Social Implications, E. Bisangwa, Pat D. Keyser

IGC Proceedings (1977-2023)

Native perennial warm-season grasses (NWSGs) of the United States (U.S.) provide valuable summer forage. Studies have shown their potential within grazing systems as a complement to cool-season forages, as well as their benefits to soil biota, wildlife biodiversity, carbon sequestration and their resiliency to extreme drought and flood events. In this paper, we demonstrate that, in addition to these benefits, NWSGs provide important economic value to beef and dairy producers as a hedge against financial risks posed by overreliance on cool-season grasses.

Breeding Forage Grasses For Increased Heat Tolerance To Combat Climate Change, Eric D. Billman, J. S. Morrison, B. S. Baldwin

IGC Proceedings (1977-2023)

The onset of climate change brings many challenges for forage production in the southeastern United States, where it is projected to become hotter and dryer in the next century. To combat this climatic challenge, recurrent phenotypic selection was conducted in growth chambers on annual ryegrass (Lolium multiflorum Lam.) and orchardgrass (Dactylis glomerata L.) to select seedlings that can germinate and survive at temperatures of 40°C. Following three cycles of selection, germination was increased from < 5% to 45% in annual ryegrass, and from 20% to 80% in orchardgrass. The rate of germination also increased, in both species by a factor of 8x that of the base germplasm. Realized heritability also increased by 40 – 45% for each species by the end of the project. This work successfully improved a quantitative trait using recurrent phenotypic selection using growth chambers as a stable environment and provided the basis for combatting climate change in other outcrossing forage species.

Breeding Small Grains As A Forage, Silage And Cover Crop For The Southern Coastal Plain (Usa) In A Changing Climatic Environment, A. Blount, Marcelo O. Wallau, S. A. Harrison, Cheryl L. Mackowiak, A. Babar, José C. B. Dubeux Jr.

IGC Proceedings (1977-2023)

Forage breeding of small grains in the southern Coastal Plains region of the U.S. mimic many other countries experiencing climate changes and breeding strategies should be similar for improving small grains grown for forage, silage or as cover crops. Significant focus on improvements in stress-adaptation has encouraged members of the SunGrains cooperative to cross, evaluate and develop experimental lines with inherent adaptation to climatic conditions including heat stress, drought tolerance, short-day and long-day forage production periods, and flooded conditions for events with storm-related, short-term durations. Many new cultivars, grown throughout the southeastern U.S. have resulted from breeding selection under abiotic …

Industry Perspectives, Challenges, And Opportunities To Enhance Alfalfa In Warm Climates, J. H. Bouton

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.; aka lucerne) acreage is low in comparison to perennial grasses in warm humid regions. This includes the tropics and subtropics, and in the USA, the Southeastern states. The alfalfa seed industry therefore saw few reasons to target sales and marketing in these regions. This overlooked logical opportunities. In this paper, these opportunities are examined for Southeastern USA. The Southeast contains a majority of beef herd, a high percentage of the dairy herd, and millions of acres suitable for conversion to alfalfa. Alfalfa is also now viewed as the best crop to solve problems inherent with …

Cooperative Evaluation Of Western Hemisphere Grassland Germplasm In Inner Mongolia, Prc, L K. Holzworth, Gu Anlin, J G. Scheetz, M E. Majerus

IGC Proceedings (1977-2023)

Replicated studies were established jointly by Chinese and American scientists in central Inner Mongolia. Both Asian and North American plant materials were included. Results of the Chinese plots show USA saline-tolerant species have potential to assist the Chinese with saline soil reclamation. On saline sites, USA cultivars rated the best stands and had the highest yields. Generally, Chinese desert steppe species outperformed USA upland entries with the Chinese legumes establishing the best stands and producing the most biomass.

Palatability Of Alfalfa (Medicago Sativa L.) And Orchard Grass (Dactylis Glomerata L.) Silages, R. D. Améndola-Massiotti, J. A. Burgueño, M. Concepción, L. Cruz

IGC Proceedings (1977-2023)

The objective was to compare palatability with different methodologies for characterizing silages at Chapingo Autonomous University, México. Eight silages were used resulting from an experiment which evaluated effects of cutting time (08:00 and 14:00), time of wilting (0, 1 and 2 h) and use of lactic bacteria inoculant on properties of alfalfa (Medicago sativa L.) and orchard grass (Dactylis glomerata L.) silages. Organoleptic properties (odor, color, texture, moisture) were assessed by trained observers, using as categories: excellent, good, fair and poor. Dry matter content, CO₂ rate of production and pH were also measured. For the evaluation of …

The Future Of Clovers In Forage Systems And As Cover Crops, J. H. Bouton, John R. Caradus

IGC Proceedings (1977-2023)

Clovers (Trifolium spp.) are the most widely used genera of legumes in forage systems, although only a limited number of the hundreds of perennial and annual species are commercially available. The number of varieties available within each of the main commercial species can be high and demonstrates past breeding achievements. Success relates to any clover’s ability to persist in mixtures with other forage species, across a range of soil types, management systems, and climates, while providing animal nutrition and biologically fixed nitrogen benefits. Uses range from traditional pasture mixtures with grasses to inclusion in multi-species mixtures, and as cover …

Economic Benefits Of Sustainable, Forage-Based Cattle Systems In Colombia And Nicaragua, S. Burkart, K. Enciso, M. Diaz, R. Van Der Hoek

IGC Proceedings (1977-2023)

Forage-based cattle systems play a key role in rural economies of developing countries in terms of food security and poverty alleviation, particularly in tropical Latin America. However, they are often related to being a major cause of negative environmental impacts by contributing to increased greenhouse gas emissions, land degradation, and the reduction of biodiversity. Significant resources have been allocated to research and development in forage material improvement, including selection and breeding. A broad range of improved materials were released by private and public sector actors showing superior characteristics in terms of productivity and environmental impacts compared to native or naturalized …

Fermentation Control And Ethanol Production Of Total Mixed Ration Prepared With Apple Pomace And Microbial And Chemical Additives, J. Fang, Yimin Cai

IGC Proceedings (1977-2023)

The objective of this study is to evaluate the impacts of moisture adjustment, lactic acid bacteria (LAB) inoculant and chemical additives on fermentation characteristics and ethanol production of a total mixed ration (TMR) containing apple (Malus domestica) pomace. The TMR was prepared with apple pomace, corn, wheat bran, soybean meal, timothy, and alfalfa hay. In Experiment 1, the proportion of apple pomace was 150 g/kg of dry matter (DM), and the moisture of the TMR was unadjusted (control) or adjusted to 450, 500, and 550 g/kg, respectively. In Experiment 2, the same ingredient proportions as in experiment 1 …

Modelling Leucaena Biomass Under Rainfed Production Systems Of Semiarid Regions, M. J. D. Cândido, J. L. G. Santos, A. C. R. Cavalcante, S. R. Maranhão, M. A. Santos, J. M. Osorio Leyton

IGC Proceedings (1977-2023)

The climatic variability of semiarid regions is the main source of uncertainties associated with forage and animal production, indicating a need for tools that accurately estimate forage production in order to construct a forage budgeting plan for livestock. This study simulated the biomass of Leucaena (Leucaena leucocephala) using the PHYGROW model in four locations located in Brazilian Semiarid. The work was carried out based on field data collected from 2019 to 2021. After sowing in 2018, leucaena was harvested when it reached 200 cm and to a target residual height of 70 cm. The biomass (fresh matter) was …

Canopy Characteristics And Growth Rate Of Bahiagrass Monoculture And Mixtures With Rhizoma Peanut, N. Caram, Lynn E. Sollenberger, Marcelo O. Wallau, C. H. Wilson

IGC Proceedings (1977-2023)

Understanding relationships among canopy light interception (LI), canopy height and structure, and leaf area index (LAI) informs management decisions and can improve efficiency of forage-livestock systems. In a long-term experiment in Florida, USA, we assessed the LI, LAI and sward height relationships of rhizoma peanut (Arachis glabrata Benth., RP)-bahiagrass (Paspalum notatum Flügge) mixed swards compared with bahiagrass monoculture to determine whether changes in canopy structure affect herbage accumulation (HA) rate due to changes in radiation use. Treatments were arranged in a semi-factorial, split-plot design (r=4). Bahiagrass monoculture and bahiagrass-RP mixtures were whole-plot treatments. Sub-plot treatments were an undefoliated …

Effectiveness And Cost Of Shrub Removal Methods In Degraded Woodlands Being Converted To Silvopasture, S. Cartoni-Casamitjana, M. J. Renz

IGC Proceedings (1977-2023)

Transforming degraded woodlands to silvopasture is of interest in the Midwestern USA as it increases profitability of farms and benefits animal health. Invasive shrubs within woodlands, however, are a major obstacle to silvopasture establishment. Research was undertaken to evaluate the effectiveness, cost and resulting herbaceous canopy light interception of common brush-control methods when used alone or integrated over a two-year timeframe. Five treatments were established in a randomized complete block design. In the first year, treatments were either forestry mowed (mow) or rotationally grazed by goats (goats) at a stocking density of 5700 to 6000 kg per hectare. In the …

Herbage Accumulation And Mass In Massai Grass Plots Mixed With Forage Peanut And Fertilized With Nitrogen, Carlos A. B. Carvalho, M. O. Leal Junior, P. P. Carneiro, J. V. B. Ramos, N. Schultz, J. C. C. Almeida, A. J. Paiva

IGC Proceedings (1977-2023)

The objective of this work was to evaluate herbage accumulation and mass during the growing season of Massai grass mixed with peanut forage and fertilized with nitrogen. The work was carried out at Federal Rural University of Rio de Janeiro, Brazil, from 11/2021 to 03/2022. A randomized block experimental design was used, in plots of Massai grass Megathyrsus maximus, in a factorial arrangement, with seven replications. Four treatments formed by the combination of the presence or absence of Archis pintoi and nitrogen fertilization (0 and 50 kg ha^-1 of N). Canopy heights of the plots were evaluated weekly …