Life Sciences Commons^™

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 …

Watermelon Fungicide Guide, Anthony Keinath, Anna Sara Hill

Horticulture

The foliar diseases gummy stem blight, powdery mildew, anthracnose, and downy mildew can reduce watermelon yields in South Carolina. Specific fungicides are needed to manage each disease. This spray guide will assist growers, Extension agents, and crop consultants recommend the appropriate fungicides based on disease symptoms and signs.

Evaluating Uv-C Hormesis On Physiological, Biochemical And Molecular Responses In Two Tomato Cultivars, Wong Gwo Rong

Student Works (2020-2029)

The growing demand for nutrient-dense fruit and vegetables presents challenges due to population growth, global climate change, limited land resources, and increasing pathogen pressure. Tomatoes, a widely consumed and nutritious fruit crop, often require high inputs of fertilisers and pesticides, raising environmental and health concerns. Ultraviolet-C (UV-C) radiation (100-280 nm), long recognised for DNA-damaging and disinfecting properties, has shown promising hormetic effects at low dosage that can enhance plant growth and post-harvest shelf-life. However, the detailed understanding of UV-C effect on flower traits, fruit quality and on molecular responses underlying plant defence remains limited. In this study, a custom UV …

Understanding Variability In Geographic Isolate Of Rotylenchulus Reniformis Across The Us Cotton Belt, Sagar Gc

All Dissertations

Management of the reniform nematode (Rotylenchulus reniformis Linford and Oliveira) in cotton (Gossypium hirsutum L.) is a challenge since the resistant cultivars lack uniformity in nematode suppression when tested across multiple geographical regions. The central hypothesis of this study was that regional variability in performance of resistant cotton cultivars is associated with unique reproduction biology (reproduction and virulence) of R. reniformis from distinct geographic origins. Greenhouse studies were conducted to assess differential reproduction biology among nine geographic population of R. reniformis originated from South Carolina (SC), Alabama (AL), Florida (FL), Arkansas (AR), Georgia (GA), Louisiana (LA), Texas (TX), …

Identification, Pathogenicity, And Fungicide Sensitivity Of Itersonilia Perplexans Associated With Petal Spot Of Gerbera Cut Flowers In Colombia, Matheus Beger

All Theses

Petal diseases significantly affect gerbera cut flower production, as minor visual damage renders flowers unmarketable. Among those pathogens causing petal spots, Itersonilia perplexans affects some Asteraceae plants. However, this pathogen's impact on Colombian gerbera remains poorly studied. This study was designed to fill four gaps: molecular identification of Colombian isolates, confirmation of pathogenicity, standardized culture media, and fungicide sensitivity data. Four objectives were pursued: (i) isolate and identify the causal agent through sequencing the Internal Transcribed Spacer, Small Subunit and Large Subunit from the rDNA; (ii) evaluate pathogenicity on detached gerbera petals; (iii) identify optimal culture media for I. perplexans …

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 …

Growth And Yield Response Of Shallots To Npk, Nk, And Humic Acid Under Different Mycorrhiza Application, Alfu Laila, Endang Sulistyorini

Jurnal Kultivasi

One strategy to increase shallot production is the utilization of microorganisms in the soil, such as arbuscular mycorrhizal fungi (AMF), which is applied together with fertilizer. This research aimed to investigate the effects of different nutrient inputs and mycorrhizal association on the growth and yield of shallots. This study used a split-plot design with three replications as blocks. The main plot included four treatments: no nutrient inputs, NPK fertilizer, NK fertilizer, and humic acid, while the subplot involved the mycorrhiza application (with or without). The measured variables included growth (plant height and number of leaves) and yield (fresh weight and …

Effects Of Phosphate-Solubilizing Fungi On Phosphorus Availability, Retention, And Soil Chemical Properties In Shallot Cultivated On Andisols Of North Sumatra, Agustina Erlinda Marpaung, Tengku Sabrina, Abdul Rauf, Dwi Ningsih Susilowati

Jurnal Kultivasi

The availability of phosphorus (P) is one of the main limiting factors for plant productivity in Andisol soils due to the strong fixation of P by allophane clay minerals, aluminum and iron oxides. Giving the phosphate solubilizing fungi (PSF) is an alternative to increase available P which plants can use to increase the yield. This study aimed to evaluate the effectiveness of phosphate-solubilizing fungi (PSF) in improving P availability on Andisol. The experiment used a block randomized design (BRD) with three replications. The first factor is Andisol soil origin (Soil 1 and Soil 2) and the second is isolate of …

Global Research On Palm Oil Diseases And Infections: A Bibliometric Analysis, Fahmi Achmad Saputra, Indria Puti Mustika, Anna Safarida, Catur Sriherwanto, Nicky Rahmana Putra

Makara Journal of Technology

The sustainability of global palm oil production faces significant threats from a range of diseases and infections affecting palm oil crops. This study presents a comprehensive bibliometric analysis to map the scientific landscape and evolution of research related to palm oil diseases over the past decade. Using data from the Scopus database, 366 relevant documents were analyzed using R and VOSviewer to uncover trends in publication volume, citation impact, prolific authors, country contributions, and keyword co-occurrence networks. The findings reveal a strong research concentration on G. boninense, highlighting its critical role as a persistent pathogen in oil palm plantations. Emerging …

Impact Of Pvc Microplastics On The Growth Of Raphanus Sativus, Olivia Fawkes, Alissia D. Fulton, Darlene Panvini

SPARK Symposium Presentations

Microplastics have emerged as a growing concern due to their increasing prevalence in terrestrial ecosystems. Understanding how microplastics affect plant growth is crucial for the agricultural industry, as crop productivity and soil quality have a direct impact on food security and farm sustainability. This study examined the impact of polyvinyl chloride (PVC) microplastics on the germination and growth rate of Raphanus sativus. Seeds were grown for six weeks in a controlled growth chamber in petri plates and soil pots containing varying concentrations of PVC microplastics (0, 25, 50, 75, 100 mg/L), including untreated PVC and PVC artificially weathered through …

Integrated Management Of Diplodia Ear Rot And A Comparison Of Stenocarpella Species Affecting Corn, Luke C. Warner

Theses and Dissertations--Plant Pathology

Corn is a globally important crop used for food, feed, and ethanol production, but often the grain quality is threatened by Diplodia ear rot, caused by Stenocarpella maydis and Stenocarpella macrospora. Effective management of Diplodia ear rot is difficult to achieve. This study evaluated the efficacy of foliar fungicides, including products listed by the Organic Material Research Institute (OMRI), against S. maydis in vitro and in field settings, as well as comparingthe aggressiveness of the two causal pathogens of Diplodia ear rot. The in vitro assays indicated a wide variation in sensitivity of S. maydis to the fungicide active ingredients, …

The Geminivirus Al2 Protein Interacts With Host Proteins Involved In The Plant Antiviral Response, Pheobean Atieno Odongo

Graduate Research Theses & Dissertations

Geminiviruses are economically important plant DNA viruses infecting a broad range of plant species and causing devastating crop diseases, resulting in up to 100% crop loss. As a result of these heavy losses on food and cash crops, these viruses represent a new threat to global food security and sustainability. In this research, I use Tomato golden mosaic virus (TGMV) to study host-virus relationships with an overall goal of developing sustainable and eco-friendly crop resistance. TGMV belongs to the Geminivirus subgroup, Begomovirus, that is characterized by a split genome consisting of two single-stranded circular DNAs. The TGMV genome encodes proteins …

Excess Nitric Oxide Alters Cellular Ph To Restrict Salicylic Acid Movement And Systemic Immunity, Fan Xia, Huazhen Liu, Keshun Yu, Xinyu Yuan, Aardra Kachroo, Pradeep Kachroo

Plant Pathology Faculty Publications

Plants carrying a mutation in S-nitrosoglutathione reductase 1 (GSNOR1) accumulate high nitric oxide (NO) and exhibit impaired immunity characterized by reduced pathogen-responsive salicylic acid (SA) accumulation and failure to activate normal SA signaling. We show that this reduced SA responsiveness in gsnor1 plants arises from impaired vascular-associated movement of SA, thereby compromising systemic acquired resistance (SAR). Elevated NO perturbs cellular pH homeostasis, acidifying the apoplast and alkalinizing the cytosol, which likely interferes with phloem-associated SA movement and renders gsnor1 plants unresponsive to foliar SA. In contrast, SA supplied via root drench restores SA signaling and SAR in gsnor1, …

Effects Of Temperature On The Life-History Traits Of Myzus Persicae And Its Efficiency In Transmitting Potato Virus Y (Pvy) In Potato Crops, Bonoukpoè M. Sokame, Henri E. Tonnang, Heidy Gamarra, Pablo Carhuapoma, Jan Kreuze, Leah R. Johnson, Ali Arab, Peter A. Armbruster, Oswaldo C. Villena

All Peer-Reviewed Publications

Aphids are highly sensitive to temperature changes and play a crucial role in transmitting plant viruses, accounting for the transmission of more than 50% of viruses that cause disease in crops. Among them, Myzus persicae is a major global pest, affecting over 400 plant species and transmitting more than 100 plant viruses, including potato virus Y (PVY), which poses a severe threat to potato crops. This study examines how temperature influences the life-history traits of M. persicae and its efficiency in transmitting PVY. Our research revealed that temperature significantly affects developmental duration, survival, and fecundity of M. persicae. The aphids …

Variable Temperature And Moisture Requirements For Germination Within Populations Of Kochia (Bassia Scoparia) In Field Margins, Brian Schutte, Rebecca Creamer

Entomology, Plant Pathology, & Weed Science: Datasets

No abstract provided.

Abiotic Stress Impacts On Macrophomina Root Rot And Nano-Encapsulated Citrus Oils To Control Fruit And Foliar Pathogens Of Strawberry, Marina J. Gutierrez

Master's Theses

Disease remains one of the major constraints to the productivity and economic success of the California strawberry industry. The most important soilborne pathogen is Macrophomina phaseolina, causing Macrophomina root rot (MRR). The most economically significant airborne pathogens include Botrytis cinerea, causing Botrytis fruit rot (BFR), and Podosphaera aphanis, causing powdery mildew (PM).

Disease severity of MRR is highly dependent on environmental factors. Therefore, understanding which abiotic stressors contribute most to disease development is crucial for effective management. A two-year field experiment at Cal Poly, SLO (2024 and 2025) evaluated the effects of drought stress, two elevated chloride …

Breeding For Disease Resistance In Melon And Watermelon, Venkata Rao Ganaparthi

All Dissertations

Watermelon and cantaloupe are two widely consumed cucurbits, but their acreage in the United States reduced by nearly 50% in last two decades. Fusarium wilt caused by a soil borne pathogen Fusarium oxysporum f. sp. niveum(Fon) race 2 is a major limiting factor in watermelon production as it reduces yields by 80%. Grafting watermelon plants onto the root stock of wild, disease-resistant varieties like ‘Carolina Strongback’ is the best strategy to manage Fon race 2. Though effective, this approach increases production costs.

Part of this dissertation focused on finding more sustainable, cost-effective solutions to control Fusarium wilt …

Effect Of Planting Date, Insecticide Efficacy, And Hail Injury On Soybean Gall Midge (Resseliella Maxima Gagné) Infestation In Soybean, Natasha Hiromi Umezu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Resseliella maxima Gagné (Diptera: Cecidomyiidae) is a recently described and economically significant pest of soybean (Glycine max (L.) Merr.) in the Midwestern United States. Since its identification in 2019, this species has become widespread and is now associated with substantial yield losses in parts of the region. Prior to its formal description, orange larvae were observed in soybean associated with plants damaged by hail, suggesting that plant injury may influence infestation. Given the pest’s economic importance, understanding the role of hail injury and developing effective, integrated management strategies are critical for mitigating its impact.

Field studies were conducted to …

Fungicidal Management Of Spring Dead Spot Using Improved Modeling And Application Strategies, Michael Vincent Battaglia

Graduate Theses and Dissertations

Spring dead spot (SDS) is a destructive disease of bermudagrass (Cynodon Rich. spp.) in parts of the world that experience winter dormancy. Fungicides are often necessary to properly manage SDS, and significant research has been conducted to improve fungicidal effectiveness. Several studies were conducted with the objectives of improving fungicide application timing, method of fungicide application, and long-term fungicidal efficiency. In the fungicide application study, a cooling degree-day (CDD) model based on soil temperatures was developed. The CDD model showed that isofetamid was highly effective against SDS during a wide application window in autumn, while tebuconazole was inconsistently effective and …

Fusarium Equiseti Pathogen Of Potato In Kenya And Its Potential In Vitro Biocontrol Using Fungal Endophytes, Marie Cecile Muhorakeye, Fathiya M. Khamis, Everlyne Samita Namikoye, Komivi S. Akutse

All Peer-Reviewed Publications

Accurate pathogen diagnosis is fundamental for effective crop disease management. In Kenya, a pathogen causing significant damage in potato farms was initially misidentified as Phytophthora infestans. This study aimed to correctly identify this pathogen and explore initial control measures using a polyphasic approach. The methodology integrated morphological observation, pathogenicity testing, and molecular analysis using ITS and EF1-α gene sequencing. The results confirmed the pathogen’s identity as Fusarium equiseti, with morphological features consistent with this species and molecular sequencing showing 99.6% identity to reference strains. This is the first official report of Fusarium equiseti as a potato pathogen in Kenya. Furthermore, …

The Development Of Tools For The Production Of Fusarium Oxysporum Race 4 Resistant Cotton Varieties, Thomas Rylands

All Theses

Fusarium oxysporum race 4 (FOV4) is a fungal pathogen that infects cotton (Gossypium spp.) plants, resulting in fusarium wilt (FW) disease that causes significant wilting, yield loss, and eventually death. Since cotton is such an important crop globally, with tens of millions of bales of fiber produced and sold worldwide each year, it is critical to develop effective strategies to combat this pathogen. This research aims to achieve that goal through two projects: (i) develop an efficient co-culture system to test fungal treatments in vitro, and (ii) develop a computer vision pipeline to more accurately assess plant resistance …

Streamlined Real-Time Qpcr Detection Assay And Nucleic Acid Extraction Protocols For Leaf Scald And Ratoon Stunt Disease In Louisiana, Joao Vitor Pelizzaro Morales

LSU Master's Theses

Leaf scald (LS) and ratoon stunt disease (RSD) are important sugarcane diseases that can cause yield losses. LS and RSD are caused by the vascular system-inhabiting bacteria Xanthomonas albilineans and Leifsonia xyli subsp. xyli, respectively. As using pathogen-free sugarcane propagative material is an important management strategy against LS and RSD, accurate and efficient pathogen detection is crucial. Our study aimed to increase pathogen detection sensitivity and efficiency through a cost-effective real-time PCR protocol and high-throughput DNA extraction methods. A SYBR-based qPCR assay detecting the RSD and LS causal agents was 100 times more sensitive than traditional PCR. Additionally, multiplex …

Interview With Orca Award Winner James Van Etten, Unl Plant Pathology; Discoverer Of Giant Viruses, Mark Griep, James Van Etten

UNL ORCA Interview Series

Dr. James Van Etten was awarded the UNL Outstanding Research and Creative Activities Award in 1992. He was born in Virginia but grew up Peoria, Illinois. Something in his youth must have sparked an interest in science because he earned his bachelor’s degree in biology from Carleton College in 1960. Carleton is a well-regarded liberal arts institution in Northfield, Minn., about 400 miles from Peoria. Next, Jim earned a master’s and doctorate at the University of Illinois in Champaign-Urbana, both in plant pathology. For his postdoctoral work in 1965 and 1966, he did postdoctoral work in the Department of Genetics …

Detection Of Sweet Potato Feathery Mottle Virus Infection Via Remote Hyperspectral Imaging, Clayton Blake

LSU Master's Theses

In sweetpotato, global production exceeds 90 million tons annually, yet yields are threatened by numerous pathogens, including the potyvirus sweet potato feathery mottle virus (SPFMV). Virus infections can reduce yields by 25–40%, but surveillance is hampered by asymptomatic infections and the labor-intensive nature of detection. Hyperspectral imaging (HSI), combined with machine learning (ML), offers a promising pathway to scalable, non-destructive detection; however, studies focused on virus infection in sweetpotato remain limited.

This study demonstrates the feasibility of ML-enabled HSI for SPFMV detection under greenhouse conditions via a curated spectral library of two commercial cultivars, 'Beauregard' and 'Orleans', and the biological …