Agronomy and Crop Sciences Commons^™

Effective Selection For Tolerance To Grass-Killing Herbicides In Perennial Ryegrass (Lolium Perenne L.), C E. Wright, J S. Faulkner

IGC Proceedings (1977-2023)

The aim of grassland reseeding is to establish a high-quality sward of improved herbage cultivars. To obtain the maximum value from the improved sward, weed invasion should be prevented. Herbicides are the main tool available. There are many herbicides for selectively controlling dicotyledonous, but not graminaceous, weeds. The control of graminaceous weeds would be possible in swards of grass cultivars selected for tolerance to grass-killing herbicides. Two cycles of recurrent selection for glyphosate tolerance in Lolium perenne L. were carried out by spraying large seedling populations with critical dosages in the greenhouse and intercrossing the survivors. It was found that …

Selection For Specific Leaf Weight In Reed Canarygrass And Its Effects On The Plant, I T. Carlson, D K. Christensen, R B. Pearce

IGC Proceedings (1977-2023)

Specific leaf weight (SL W, dry weight/unit leaf area) may serve as a selection criterion for forage yield through a positive rela• tionship with photosynthesis. Two cycles of phenotypic selection for high and low SLW were conducted in reed canarygrass (Phalaris anmdinacea L.) to investigate direct and correlated responses, particularly those related to yield and quality of forage. In a space-planted test, average direct responses from two cycles of selection for high and low SLW were 23% and 19%, respectively. Significant correlated responses were obtained for ten traits. Compared with the low-SLW cycle-2 population, the high SLW cycle-2 population averaged …

Value Of White Sweet Lupin In Production Of Protein Fodder And Feeding Of Animals, O Saric, I Ramosevac

IGC Proceedings (1977-2023)

The potential of white sweet lupin (Lupinus albus L.) as a grain or forage feed for livestock was investigated in a series of ex­periments. Grain yield of lupin was greater than or equal to that of soybeans (Glycine max [L.] Merrill) in most evaluations. The quality of lupin seed compared favorably with that of soybean meal and fishmeal. Lupin is capable of producing large amounts of forage in a short period, making it a good prospect for forage production in regions that have a short growing season.

Genetic Variability For Morphological And Agronomic Characters In Desmodium Uncinatum (Jacq.) D.C. And D. Intortum (Mill.) Urb., E.M P. Oliveira, P S. Martins, A B. Cruz

IGC Proceedings (1977-2023)

Objectives of this research were to study the performance of eight populations of D. unicinatum and ten populations of D. intortum, with relation to morphological and agronomic characters to estimate the genetic variation between populations and between plants within populations, and to estimate genetic and phenotypic parameters for these characters.

White Clover: An Olde Crop With A Promising Future, P B. Gibson, W E. Knight, G W. Barnett, W A. Cope, J D. Miller

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) is a widely adapted, important forage legume for grazing in the U.S. The palatability and quality of the forage, the wide adaptation of the plants to growth in different climates and under various grazing conditions and the role it plays in supplying nitrogen to pastures make white clover our finest pasture legume. The use of adapted white clover cultivars should result in large economic gains to the livestock industry in the U.S .A. Beef and dairy farmers would profit from reduced need for nitrogen fertilizer, an extended grazing season, increased forage pro­duction and quality, better …

Performance And Variability Of Agronomic Characters In Populations Of Stylosanthes Guianensis (Aubl.) Sw., P S. Martins, N A. Vello

IGC Proceedings (1977-2023)

Stylosanthes guianens-is (Aubl.) Sw. shows wide variations in morphological and physiological characteristics, and basic infor­mation on genetic variability is needed for future breeding programs. The objectives of this paper were to evaluate 25 native Brazilian populations of S. guianensis for forage characteristics · • ;10,d • to estimate genetic and phenotypic parameters for these characters. The experiment was conducted in a duplicated 5 x 5 balanced lattice design with plots that contained 4 individuals spaced on 2-m centers. The following characters were evaluated after the beginning of flowering period: days to flowering (DF), mean diameter (MD), basal area (BA), growth …

Rhizoma Peanut: Perennial Warm-Season Forage Legume, G M. Prine

IGC Proceedings (1977-2023)

Rhizoma peanut is the common name given species in section Rhizomatosae of the genus Arachis. Florigraze rhizoma peanut (A. glabrata Benth.) has been released as a cultivar by the Florida agricultural experiment stations and the USDA Soil Conserva­tion Service. Florigraze is adapted to the well-drained soils of Florida and the warm humid tropics and subtropics around the world. Rhizoma peanuts are propagated by rhizomes, which in Florida are best planted during winter. The slowness of coverage during early establishment is the biggest shortcoming of rhizoma peanuts. If they are established first, rhizoma peanuts will grow well in mixture with bermudagrass …

Hedysarum Mongolicum Turcz.: An Important Protein Resource Legume On Dry Sandy Land, Li Min, A W. Hovin

IGC Proceedings (1977-2023)

In searching for plants that can both increase the protein production and improve the sandy-soil conservation of the grassland in the arid, windy regions of North China, so far, from among many native plants, we have identified Hedysarum mongolicum Turcz. as the best species to fulfill our dual purposes. We investigated its distribution, planted its native seeds in the Maowusu desert, and studied it under its native and cultivated growing conditions from 1957 to 1964. Chinese farmers call this perennial subbrush legume of the sweetvetcb genus "Yang Cai," meaning "sheep like to eat." It can thrive in the stable or …

Adaptation And Utilization Of Three Legume In China, Huang Wenhui

IGC Proceedings (1977-2023)

China is a vast territory with extremely varied climates, soil, and topography, and it is very rich in pasture grass resources. The main legumes for forage are Alfalfa (Medicago sativa L.), yellow alfalfa (Medicago folcata L.) and shadawang (Astragalis adsurgent Pall.)

Preliminary Evaluation Of Legume Germ Plasm In The Cerrados Of Brazil, D Thomas, R P. De Andrade

IGC Proceedings (1977-2023)

In 1978 an evaluation program was initiated to select legumes that (1) grow and produce seed on acid soils under aluminum and water stress, (2) persist under grazing, and (3) tolerate pests and diseases. The work is being conducted at the Cerrados Agricultural Research Center, near Brasilia, at lat 15°S and altitude 1,000 to 1, 100 m . Annual rainfall is 1,500 mm, mostly distributed in a 6-month wet season, and mean annual temperature is 21°C. Nine hundred legume accessions from thirteen genera have now been established as spaced plants on the 2 major soil types of the region. The …

Genetics And Utilization Of Apomixis For The Improvement Of Guineagrass (Panicum Maximum Jacq.), Y H. Savidan

IGC Proceedings (1977-2023)

Natural polymorphism in guineagrass (Panicum maximumjacq.) has been stabilized in tetraploid biotypes by apomixis. Sex­ual diploids were found in East African populations. Our objective was to determine whether apomixis could be related with a simple genetic background and manipulated in an improvement program. Apomicts of guineagrass are characterized by a 4-nucleate embryo sac structure, and this trait was used in genetical analyses to differentiate apomictic from sexual hybrids. Progeny tests were also conducted as controls. Ten different types of progenies were analyzed: tetraploid sexual (from colchicine treatment of diploids) x apomictic F1 hybrids; selfed and backcrossed progenies of sexual F1 …

Breeding Challenges In Apomictic Warm-Season Grasses, E C. Bashaw, P W. Voigt, B L. Burson

IGC Proceedings (1977-2023)

Efforts to breed apomictic grasses met with little success in the past, but results of more recent research show significant progress with some species and new prospects for improving apomicts. Early research uncovered the cytological basis for apospory and diplospory, found the common apomictic mechanisms in grasses, and showed that apomixis is transmitted from pannt to offspring. Discovery of sexual or partially sexual (facultative apomicts) plants in several species formerly considered obligate apomicts allowed for hybridization and genetic studies. Results of subsequent research confirmed inheritance of apomixis, and data from the more conclusive studies indicate that method of reproduction …

Evaluating Soil Health And Crop Yield In Louisiana Agricultural Systems: Impacts Of Best Management Practices And Prediction Models, Hector J. Mendoza Lagos

LSU Doctoral Dissertations

The adoption of conservation management practices is critical for improving soil health, enhancing nutrient use efficiency, and sustaining crop productivity in row crop systems in Louisiana. This study evaluated the role of conservation agronomic practices, soil biochemical indicators, and machine learning predictive models to improve soil nutrient dynamics, soil health indicators, microbial communities (MC), and crop productivity on a corn (Zea mays L.) research plot scale and in a commercial forty-hectare cotton (Gassypium hirsutum L.)-corn-soybean (Glycine max L.) rotation system in northeast Louisiana. The objectives of the study were to evaluate soil nutrient dynamics and MCs under …

Evaluating The Impact Of Intercropping Vegetables And Cut Flowers On Yield And Conservation Biological Control, Alliance Igiraneza

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Specialty crops such as vegetables are some of the most susceptible to yield losses and increased management difficulty over time due to pests. One of the potential solutions to this problem, which aims at ensuring the sustainability of the sector, is using conservation biological control practices such as intercropping to increase diversity, while maintaining the economic feasibility and profitability of the system. This study was conducted to evaluate the impact of this management practice using Bell pepper (Capsicum annuum var. King Arthur) as the main crop, intercropped with flowers including zinnia (Zinnia elegans var. Benary’s Giant), sunflower ( …

Cis-Variant Gene-Expression Association Analysis: A Targeted Approach To Identify Functional Cis-Regulatory Variation, Sofiya Arora

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Phenotypic diversity in plants is largely driven by changes in gene function arising from mutations in both the coding and regulatory regions. Regulatory variation is particularly pervasive because it can fine-tune gene expression without disrupting protein function and is therefore less likely to be strongly selected against in natural populations. As a result, it has played a central role in evolution and domestication. In our previous genome-wide eQTL mapping study in maize, nearly two-thirds of the expressed genes were found to harbor detectable cis-expression quantitative trait loci (cis-eQTLs) with strong local effects on gene expression. Though these cis-variants are widespread, …

Effects Of Applying Humic Acid In-Furrow At Potato Planting, Jonathan Tyler Price

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Many products are marketed towards potato farmers that purport to have a positive return on investment for yield and quality. Humic acids, which are comprised of long chained, organic molecules that can be naturally or industrially made, are currently being marketed in this way. The use of these materials is reported to improve nutrient uptake, increase soil health, encourage vigorous growth, and most importantly, increase yields.  From 2023-2025, the in-furrow application of humic acid containing commercial products was evaluated in Pennsylvania on the cultivars ‘Lehigh’ and ‘Waneta’. Black Label Zn, Duo Maxx, Fertiactyl RhiZn, Humi-flex FA, Hydra-Hume, and Monty's Liquid …

Dried Water Treatment Residuals Might Be An Option To Reduce Soluble Reactive Phosphorus Release From Soils, Katie B. Mckay

Biological and Agricultural Engineering Undergraduate Honors Theses

Nonpoint source pollution from agricultural landscapes contributes to freshwater eutrophication, with legacy phosphorus (P) in soils potentially driving soluble reactive phosphorus (SRP) losses to surface waters. The objectives of this study were to evaluate SRP adsorption by dried water treatment residuals (WTRs) produced by Beaver Water District, quantify reductions in soil SRP release across increasing WTR application rates, and compare dried WTR performance to prior WTR studies.

Dried WTRs (~98% solids) were assessed using batch sorption experiments and soil core incubations. Phosphorus sorption was measured by mixing WTRs with CaCl₂ solutions containing increasing SRP concentrations and fitting results to …

Arkansas Soybean Research Studies 2024, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

The 2024 Arkansas Soybean Research Studies includes research reports on topics pertaining to soybean across several disciplines from breeding to post-harvest processing. Research reports contained in this publication may represent preliminary or only data from a single year or limited results; therefore, these results should not be used as a basis for long-term recommendations. Several research reports in this publication will appear in other University of Arkansas Division of Agriculture’s Arkansas Agricultural Experiment Station publications. This duplication is the result of the overlap in research coverage between disciplines and our effort to inform Arkansas soybean producers of the research being …

Discovering The Genetics Underlying Speciation Traits In Heuchera (Coral Bells), Tajinder Singh

Honors Theses

Hybridization is a key evolutionary mechanism for generating biological diversity, ultimately shaping diversification and adaptation of plant lineages in natural and agroecosystems.  Our understanding of the frequency, distribution, and significance of hybridization is rapidly increasing, but the external driving forces that dictate why certain species hybridize, and others do not remain obscure. The physical traits that shape gene flow and trait sharing among species are likely to be among the key factors that directly control hybridization. Gene flow in most plants is mediated by pollinating insects and thus by pollination syndromes, which are suites of floral traits that have evolved …

Response Of Chlorophyll, Morphology, And Yield Of Several East Java Superior Soybean (Glycine Max L.) Varieties To Levels Of Salinity, Puji Lestari Tarigan, Ida Retno Moeljani, Fadila Suryandika, Hadi Munarko

Jurnal Kultivasi

Soybean production has been extended to saline areas. This development is a strategy to expand planting areas to suboptimal land to increase worldwide production. To support cultivation in these locations, it is necessary to develop superior varieties that are resistant to salinity and provide supporting technological inputs. In saline conditions, soybeans may face stress that leads to morphological, physiological, and yield disturbances. Consequently, the response of several soybeans in East Java should be observed. This study is a pot experiment and arranged in a Factorial Completely Randomized Design (CRD) consisting of two factors, soybean varieties and NaCl concentrations. The treatments …

Effects Of Spatially Targeted Fertilizer Strategies On Canopy Growth Across Contrasting Tart Cherry Orchard Sites, Kurt Wedegaertner, Brent Black, Matt Yost, Grant Cardon

Plants, Soils and Climate Student Research

Variable-rate fertilization is increasingly promoted in perennial orchard systems, but its effectiveness remains difficult to predict because tree responses are often inconsistent and strongly conditioned by site-specific constraints. To address this, we evaluated soil-based and vigor-based zoning frameworks across four commercial tart cherry (Prunus cerasus) orchards representing contrasting soil conditions, canopy structures, and management histories. Within each orchard, management zones were defined using either soil apparent electrical conductivity (ECa) or satellite-derived canopy vigor. Fertilization strategies were implemented by varying fertilizer application timing among zones using split-application approaches while maintaining a constant total fertilizer rate. Tree-level canopy structure was …

Soil Nutrient Sufficiency Does Not Ensure Plant Nutrient Status, Chandralekha Joga Miss

Scholars Week

Soil testing is commonly used to guide nutrient management. However, plants may not use nutrients in the same way that soil tests predict. This can happen when nutrients interact and limit uptake. This study evaluated whether soil test results match plant nutrient status under different compost levels, with a focus on nutrient antagonism. Soils from three compost histories were used: no compost (T1), moderate compost (T2), and long-term high compost from repeated hog manure application (T3). Soils were mixed with ProMix and Perlite (1:1:1), and Chijimisai was grown under greenhouse conditions. Plant height and chlorophyll (SPAD) were measured weekly. Soil …

Assessment Of Precision Rangeland Management Tools In The Nebraska Sandhills, Hannah K. Allen

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The objective of this thesis is to evaluate tools and management strategies that contribute to rangeland monitoring and livestock distribution in heterogeneous grassland systems of the Nebraska Sandhills. Chapter one reviews relevant literature related to precision livestock management, the Nebraska Sandhills, biomass estimation, and pyric herbivory. The second chapter evaluates the use of fractional green canopy cover (FGCC) derived from the Canopeo mobile application as a rapid method for estimating aboveground biomass in Sandhills rangelands. Biomass samples were collected across topographic positions in both early and late growing season, and relationships between FGCC and clipped biomass were assessed using generalized …

Production Of Black And Navy Beans In Virginia, Harbans L. Bhardwaj, Satya S. S. Narina Ph.D.

Virginia Journal of Science

An urgent need exists in Virginia and adjoining states to identify crops to replace declining tobacco acreage. Although not traditionally grown in the region, dry beans (Phaseolus vulgaris L.) have considerable potential as alternative summer crops due to their nutritional benefits and increasing consumer demand. Information on the production potential of these crops in Virginia, however, is not yet available. To remedy this situation, replicated field trials were conducted over three years with six black and four navy bean varieties to characterize grain yields following three row spacings and three planting times. Black beans significantly out-yielded navy beans (2095 …

Arkansas Cotton Variety Tests 2025, F. Bourland, J. Gann, B. Lovelady, B. Guest Jr, J. Mcalee, L. Martin, Z. Treadway, C. Henderson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Tests is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant. These annual evaluations will then facilitate the inclusion of new, improved genetic material in Arkansas cotton production. Adaptation of varieties is determined by evaluating the lines at five University of Arkansas Division of Agriculture research sites (Manila, Keiser, Judd Hill, Marianna, and Rohwer). The tests at Rohwer were abandoned due to undefined …

Genome Wide Association Study (Gwas) On Different Economic Traits And Epigenetic Stability Of Sweetpotato In Louisiana, Ajay Dhungana

LSU Doctoral Dissertations

Sweetpotato [Ipomoea batatas (L.) Lam] is a globally important food, feed, and industrial crop, yet its improvement is constrained by a complex hexaploid genome, clonal propagation, and susceptibility to multiple diseases. In Louisiana, production is threatened primarily by Fusarium oxysporum f. sp. batatas (Fusarium wilt) and Ceratocystis fimbriata (Black rot). Furthermore, the in vitro propagation methods essential for disease-free planting material and germplasm conservation can introduce epigenetic instability that undermines clonal fidelity. This dissertation integrates genome-wide association studies (GWAS), genotype by environment interaction (GEI) and DNA methylation profiling to dissect resistance mechanisms and assess epigenetic stability in Louisiana sweetpotato …

Vertical Price Transmission In The Philippine Rice Supply Chain: Responses To Shocks In The Post-Tariffication Period, Bates Bathan

The Philippine Agricultural Scientist

In the post-Rice Tariffication Law (RTL) period, several protectionist policies and state interventions have reemerged in the Philippine rice market. Using national-level time series data from January 2018 to April 2025, the study applies autoregressive distributed lag models to assess the impact of policy changes and external shocks on unmilled rice (palay) and rice prices. Results show that National Food Authority (NFA) rice stocks significantly affect palay farmgate prices and special rice retail prices. Vertical price transmission flows from farmgate to wholesale levels for special rice, and from wholesale to retail levels for well-milled and regular-milled rice. Major …

The Dual Nature Of Weedy Rice (Oryza Sativa F. Spontanea): From A Noxious Weed To An Important Genetic Resource For Rice Improvement, Rica M. Rentino, Vanessa Sernicula, May O. Palanog, Roselyn G. Alfetche, Dan Michael A. Angay, Francis L. Tejada, Dexter G. Balboa, Shaireen M. Angay, Fatima-Nasra A. Sahadain, Teodora E. Mananghaya, Karl Vincent J. Jose, Liezel C. Llanes, Jonathan M. Niones, Karla Mae R. Nonog, Frodie F. Waing, Leonilo Gramaje, Albert Christian S. Suner, Ommal H. Abdulkadi, Norvie L. Manigbas, Jose E. Hernandez, Alvin D. Palanog

The Philippine Agricultural Scientist

Weedy rice (Oryza sativa f. spontanea) is becoming a serious threat to rice production in the Philippines, especially in direct-seeding rice areas, owing to its high competitiveness and its similarity to cultivated rice in morphology and ecological requirements. However, weedy rice can be considered both a threat that endangers rice production and an opportunity, as it offers a potential source of novel genes for rice improvement. This study evaluated the extent of weedy rice infestation in direct-seeding areas in the Visayas, measured the phenotypic and genotypic diversity of collected weedy rice ecotypes using simple sequence repeat (SSR) markers, and …

Integrative Effects Of Mycorrhizal Fungi, Azotobacter, And Azospirillum With Different Nitrogen Levels On Morphophysiological Responses And Drought Tolerance Of Maize (Zea Mays L.) ‘Sc706’ Under Varying Water Deficit Conditions, Nozar Shamohammadi, Mahdi Zare, Korosh Ordookhani, Farshid Aref, Shahram Sharafzadeh

The Philippine Agricultural Scientist

Under drought stress, soil fertility declines sharply, restricting nutrient availability and reducing plant productivity. This study evaluated the effects of mycorrhiza, Azotobacter, and Azospirillum combined with nitrogen on the morpho-physiological traits of maize (Zea mays L.) hybrid SC706 plants under different water deficit conditions. The experiment was conducted at a research field in Fars Province, Iran, over 2 consecutive years (2017–2018, 2018–2019) and applied a split-split plot design based on a Randomized Complete Block Design (RCBD) with 3 replicates. It assessed the effects of the 3 biological fertilizers in 4 treatment groups (Control [B1], inoculation with mycorrhiza alone …

Heterosis For Flowering Time And Leaf Traits In F1 Hybrids From Desi And Kabuli Chickpeas [Research Note], Gizem Kamçi, Behiye Tuba Biçer

The Philippine Agricultural Scientist

The study was conducted at the Faculty of Agriculture in Dicle University, Southeast Anatolia, Türkiye, during the 2023 growing season to estimate heterosis, heterobeltiosis, and dominance for phenological, leaf, and plant traits in F₁ hybrids from desi × kabuli and kabuli × kabuli chickpea crosses. In 2022, 2 desi (Black, ICCV 10) and 3 kabuli (Azkan, ILC 533, ILC 482) chickpea varieties were crossed, producing 10 hybrids and 5 parents evaluated in a randomized complete block design with 3 replications. Significant variation was found among genotypes for all traits. Days to first flowering ranged from 55.7 to 69.0 d, with …