Plant Sciences Commons^™

Machine Learning-Based Soybean Yield Prediction And Optimizing Lidar-Mounted Uav Efficiency, Leticia Santos

LSU Master's Theses

The first chapter of this thesis explores the predictive capabilities of random forests algorithm on datasets obtained from field plot experiments on crop management systems in soybean. Furthermore, the chapter presents a complementary analysis of model performance according to dataset sizes and two techniques on how to impute and deal with missing data. Random forests are being compared with standard statistical techniques such as linear regression on a well-structured, information-rich agronomic experiment. The key findings of this chapter includes the best hyperparameters adjustment and the identification of the dataset threshold for optimal algorithms performance. The second chapter has a research …

A Global-Temporal Analysis On Phytophthora Sojae Resistance-Gene Efficacy, Austin G. Mccoy, Richard R. Belanger, Carl A. Bradley, Daniel G. Cerritos-Garcia, Vinicius C. Garnica, Loren Giesler, Pablo E. Grijalba, Eduardo Guillin, Maria A. Henriquez, Yong Min Kim, Dean K. Malvick, Rashelle L. Matthiesen, Santiago X. Mideros, Zachary A. Noel, Alison E. Robertson, Mitchell G. Roth, Clarice L. Schmidt, Damon L. Smith, Adam H. Sparks, Darcy E.P. Telenko, Vanessa Tremblay, Owen Wally, Martin I. Chilvers

Papers in Plant Pathology

Plant disease resistance genes are widely used in agriculture to reduce disease outbreaks and epidemics and ensure global food security. In soybean, Rps (Resistance to Phytophthora sojae) genes are used to manage Phytophthora sojae, a major oomycete pathogen that causes Phytophthora stem and root rot (PRR) worldwide. This study aims to identify temporal changes in P. sojae pathotype complexity, diversity, and Rps gene efficacy. Pathotype data was collected from 5121 isolates of P. sojae, derived from 29 surveys conducted between 1990 and 2019 across the United States, Argentina, Canada, and China. This systematic review shows a loss of efficacy of …

Mycorrhizal Feedbacks Influence Global Forest Structure And Diversity, Camille S. Delavaux, Joseph A. Lamanna, Jonathan A. Myers, Richard P. Phillips, Salomón Aguilar, David Allen, Alfonso Alonso, Kristina J. Anderson-Teixeira, Matthew E. Baker, Jennifer L. Baltzer, Pulchérie Bissiengou, Mariana Bonfim, Norman A. Bourg, Warren Y. Brockelman, David F.R.P. Burslem, Li Wan Chang, Yang Chen, Jyh Min Chiang, Chengjin Chu, Keith Clay, Susan Cordell, Mary Cortese, Jan Den Ouden, Christopher Dick, Sisira Ediriweera, Erle C. Ellis, Anna Feistner, Amy L. Freestone, Thomas Giambelluca, Christian P. Giardina, Gregory S. Gilbert, Fangliang He, Jan Holík, Robert W. Howe, Walter Huaraca Huasca, Stephen P. Hubbell, Faith Inman, Patrick A. Jansen, Daniel J. Johnson, Kamil Kral, Sabrina E. Russo, Et Al.

Faculty Publications from the Center for Plant Science Innovation

One mechanism proposed to explain high species diversity in tropical systems is strong negative conspecific density dependence (CDD), which reduces recruitment of juveniles in proximity to conspecific adult plants. Although evidence shows that plant-specific soil pathogens can drive negative CDD, trees also form key mutualisms with mycorrhizal fungi, which may counteract these effects. Across 43 large-scale forest plots worldwide, we tested whether ectomycorrhizal tree species exhibit weaker negative CDD than arbuscular mycorrhizal tree species. We further tested for conmycorrhizal density dependence (CMDD) to test for benefit from shared mutualists. We found that the strength of CDD varies systematically with mycorrhizal …

Opening Speech, Ray Smith

IGC Proceedings (2001-2023)

No abstract provided.

Biodiversity—The Birds And The Bees And Healthy Grasslands, D. Borrenpohl, Pat D. Keyser

IGC Proceedings (2001-2023)

Losses in biodiversity abound in modern agroecosystems, and biodiversity loss hampers ecosystem function and primary productivity comparable to abiotic stress. One of the most endangered ecosystems in the world is North American tallgrass prairie, and native birds and pollinators that historically depended on tallgrass prairie are in precipitous decline. Fortunately, native warm-season grasses that dominated tallgrass prairie present a valuable opportunity for summer forage to beef producers in the Eastern United States—a time when coolseason grasses endure a lack in productivity called the “summer slump.” Tallgrass prairie was sustained by periodic disturbance from grazing and fire, and combining fire and …

The Soil Health Properties Of Native Grasslands, C. Bitler, Pat Keyser

IGC Proceedings (2001-2023)

Due to an increased interest in soil health and the role soils can have in carbon sequestration, native grasslands are getting heightened attention. Native grasslands are known for their deep top-soils that develop over time through the accumulation of soil organic matter. The deep and fibrous root systems that make up two-thirds of the biomass of native grasslands are the primary contributors to the soil organic carbon (SOC) content of grassland soils. Increased SOC content has a cascading effect on soil health metrics through increasing water infiltration and water holding capacity, supporting diverse and abundant soil microbial life, and improving …

Using Functional Ecology To Predict Restoration Success In Managed Grasslands, J. Bergman

IGC Proceedings (2001-2023)

Plants have developed remarkable functional variation over evolutionary time to cope with different environmental conditions. As a result, functional variation – measurable as functional traits above and below ground – can be found within but also among grassland communities today. The functional space covered by a community is thereby restricted by environmental factors while each single species within the community inhabits a specific niche with a certain breadth along different environmental gradients. Data from field sampling in European grasslands have shown, that species intraspecific functional variation can cover considerable amounts of possible functional spaces, hence holding the potential to establish …

Toxic Plants In Grasslands And Their Impact On Livestock, A. C. Barr

IGC Proceedings (2001-2023)

Grasslands are critical infrastructure for most cow/calf operations. Quality and abundance of pasture grasses directly influence livestock rate of gain, thereby affecting livestock margins and production costs, which determine the profitability of stocker operations. Successful cattlemen control weeds to preserve healthy pasture but also to prevent plant poisonings that may reduce individual animal performance or cause fatalities. Integrated Toxic Plant Management (ITPM) programs teach ranchers to identify the potentially toxic plants, recognize symptoms of plant poisonings, and use appropriate strategies to control those plants. Toxic plants can produce a range of effects in cattle and other grazing species. Nightshades ( …

Response Of Reproductive Phenology To Soil Water Content Of Stipa Breviflora Under Warming And Nitrogen Application, L. Bai, H. Y. Ren, G. D. Han

IGC Proceedings (2001-2023)

Plant phenology is considered as the most direct and sensitive characteristic indicators of plant response to regional climate change. Based on the observation data of phenology and soil water content of Stipa breviflora in an experimental platform of warming and nitrogen application in Inner Mongolia desert steppe from 2009 to 2019. The results showed that warming and nitrogen application significantly advanced the reproductive phenological period (P < 0.001), and the interaction of warming and nitrogen application promoted the advance of reproductive phenological period (P < 0.05).

Conference Agenda, Igc

IGC Proceedings (2001-2023)

No abstract provided.

Modelling Basal Area Of Perennial Grasses In Australian Semi-Arid Wooded Grasslands, S. G. Marsden, K. C. Hodgkinson

IGC Proceedings (2001-2023)

In many semi-arid pastoral systems, landscape processes easily become dysfunctional. Shifts to less functional states may be irreversible, and have long-term consequences for pastoral profitability and social viability of rural communities. Typically, shifts to lower functional states involve a decline in perennial grasses (Hodgkinson, 1994). Here we develop a conceptual basis for modelling the basal area of perennial grasses in a semi-arid grassland and validate the model using data from a 10-year grazing study.

The Effect Of Manipulated Conservation Margins In Intensively Grazed Dairy Paddocks On The Biodiversity Of Pteromalidae And Braconidae (Hymenoptera: Parasitica), A. Anderson, G. Purvis, A. Helden, H. Sheridan

IGC Proceedings (2001-2023)

Conserving field margins provides an opportunity to enhance biodiversity in agricultural landscapes. The parasitoid Hymenoptera represent one of the most diverse and biologically specialised of all insect groups and play an important role in insect pest control (LaSalle & Gauld, 1993). The diversity of parasitiods in any habitat is theoretically likely to reflect the diversity of host taxa. The aim of this study was to assess the effects of field margin manipulations on the diversity of parasitoids as a wider indication of effects on general arthropod diversity.

Plant Diversity Patterns Along Altitudinal Gradient In Understory Communities Of Darkesh Region, Bojnord, Iran, A. Arjmandi, H. Ejtehadi, F. Memariani, Mansour Mesdaghi

IGC Proceedings (2001-2023)

The ecotone region of Darkesh with an area of 22,500 hectares is located in the Irano-Turanian xeric-continental bioclimatic zone of Khorassan-Kopet Dagh. To investigate the plant diversity patterns of understory communities along three elevation classes of 1100-1600, 1600-2100, and 2100-2600 m, 187 plots were sampled randomly and abundance and cover of species were recorded using 4-m² plots. Beta diversity and Hill indices were calculated by using R and PAST software. A total of 252 species were recorded including 31 perennial grasses. The most abundant grasses were Poa nemoralis, Poa bulbosa, Bromus sterilis, Brachypodium sylvaticum, and Dactylis glomerata subsp. glomerata …

Using Genetic Diversity In Deep Root Systems Of Perennial Forage Grasses And Rice To Capture Carbon In Tropical Soils, J. Arango, Daniel M. Villegas, R. N. Jauregui, J. A. Cardoso, C. Costa Jr., C. Rebolledo, M. F. Alvarez, M. Selvaraj, L. Rodriguez, M. Mayorga, P. Chavarriaga, A. Notenbaert, M. Quintero, M. Da Silva, Manabu Ishitani, M. Peters, I. Rao, Joe Tohme

IGC Proceedings (2001-2023)

Agricultural soils have the potential not only to be sinks of carbon dioxide (CO₂) but also to mitigate the emissions of this gas to the atmosphere, thus, alleviating global warming. Perennial tropical grasses and rice upland and lowland varieties exhibit a large untapped genetic diversity in their root systems (e.g., deep rooting ability, exudation rates and chemical composition) that, if unlocked, could contribute to increased food production in crop-livestock systems while enhancing soil organic carbon (SOC) in tropical regions. Naturebased solutions that improve crop adaptation and SOC storage in tropical soils could help to remove CO₂ from …

Salt Tolerance Mechanisms In Perennial Fodder Grasses, Edna Antony, B. Aravind, A. Amulya, T. Anushree, P. V. Rakshata, F. H. Savitha, M. B. Doddamani, P. V. Kuligod, Akbar, Vinod Kumar, K. Sridhar, Vijay Kumar Yadav

IGC Proceedings (2001-2023)

Salinity stress is one of the most damaging stresses in crop plants. It reduces the productivity of the soil and makes it unsuitable for crop cultivation. Fodder crops are considered the best alternative in such uncultivable land. Using salinity-affected land for pasture development is the best alternative to utilize such lands. However, the extent of salinity tolerance varies among different grass species. In this study, Pearl millet Napier hybrids (PMN hybrid) and guinea grass varieties were studied for salinity tolerance in artificially created saline soils in the ratio of 13:7:1:2 (NaCl: Na₂SO₄: MgCl: CaSO₄, …

Effect Of Soil Nitrogen And Water Content On The Establishment Of A Lolium Perenne L. And Trifolium Repens L. Pasture, M. F. Alonso, Oscar A. Balocchi, I. Calvache, O. Martínez

IGC Proceedings (2001-2023)

Climate change has decreased rainfall in Southern Chile affecting the productivity of the grasslands that sustain the dairy and beef cattle industries. These grasslands are mainly mixtures of Lolium perenne L. and Trifolium repens L. Thus, we study the response on the establishment of a mixture of these two species to three levels of soil water content and two levels of nitrogen (N) fertilization. The trial was carried out in containers sowed in a complete randomized block´s design. Soil moisture measurements were taken daily. N fertilizations was applied at the establishment and every 60 days. Leaf appearance rate was measured …

Impact Of Level Of Use On Plant Vigor And Weight Of Festuca Humilior And Calamagrostis Vicunarum, T. Edson, L. Aguirre, E. R. Flores

IGC Proceedings (2001-2023)

Tussock grasslands of Festuca humilior and Calamagrostis vicunarum cover a significant extension of the central Andes of Peru, constituting a plant association highly appreciated by cattle ranchers. The objective of this research was to estimate the cumulative impact of the level of use of the key grasses Festuca humilior and Calamagrostis vicunarum on plant height, vigor, and weight. This study was conducted in a humid grassland of regular condition located at 4186 masl in the Puna ecoregion. The variables evaluated were: plant height, basal and canopy diameter and plant weight. The experiment lasted two years in which individual plants from …

A Multi-Model Approach To Understanding Growth, Reproduction, And Life History Strategies In Bromeliads, Erin N. Bodine

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Estimating & Modeling The Growth Of Bromeliads, Erin N. Bodine, Helen O. Udeochu, Alana G. Wells

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Investigating The Effect Of Agronomic Factors On Microbiome Of Horticulture Produce, Maryada Bohra

ORBioM (Open Research BioSciences Meeting)

The ranged microbiome in fruits and vegetables contributes substantially to the health of vegetation which, in effect, benefits human health. These microorganisms undertake an extensive variety of responsibilities including flavour creation, ripening and health preservation via the production of second-generation metabolites. There is limited information however on the influence of agronomic practices such as crop ripening stage at harvest, storage, packing material and how they impact the microbiome of the crop itself. The overall role of the crop microbiome in gut health is also not fully clear.

The Meta-Hort project will examine the effects of premature harvesting along with tray …