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The Effect Of Water Management And Ratoon Rice Cropping On Methane Emissions And Harvest Yield In Arkansas, Marguerita Leavitt

Graduate Theses and Dissertations

Sustainable intensification of rice farming is crucial to meeting human food needs while reducing environmental impacts. Rice produces 8% of all anthropogenic CH4, which is a potent greenhouse gas. CH4 emissions can potentially be reduced by cultivation practices that minimize the number of days the fields are saturated, such as dry-seeding instead of water-seeding and irrigation using the alternate wetting and drying (AWD) technique instead of delayed, continuous flooding (DF). Ratoon cropping, wherein a second crop of rice is grown from the harvested stubble of the first crop, can be used to produce additional yield with minimal labor, but may …

B.R. Wells Arkansas Rice Research Studies 2021, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 47.5% of total U.S. rice production and 47.8% of the total acres planted to rice in 2021. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …

Effect Of Irrigation Regime And Fertilization On Recovery Of Dicamba Injured Soybean, Wesley France, Jason K. Norsworthy, Trenton Roberts, Jeremy Ross, L. Tom Barber, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

With the release of the dicamba-resistant crop technology and subsequent increase in dicamba off-target movement to non-dicamba-resistant crops, discovering means of mitigating yield loss through studying dicamba injury to soybean and interactions with factors such as irrigation regime and fertilization would prove beneficial. Field experiments were conducted in 2019 in Fayetteville and Colt, Arkansas, to evaluate the effect of irrigation regime to non-dicamba-resistant soybean that was injured by dicamba at a low dose at multiple timings. Another experiment was conducted in Fayetteville in 2019 and 2020 evaluating the impact of nitrogen (N) and potassium (K) fertilization on soybean recovery following …

Environmental Weed Risk Assessment Protocol For Growing Non-Indigenous Plants In The Western Australian Rangelands, Geoff A. Moore Mr, Christine Munday Ms, Papori Barua Dr

Bulletins 4000 -

This bulletin is a post-border environmental weed risk assessment (WRA) protocol which is based on the Environmental WRA Protocol developed for the Future Farm Industries Co-operative Research Centre (FFI CRC), but with some changes to reflect the different environment and objectives.

The WRA protocol was developed specifically as a post-border assessment of non-indigenous species that may have agricultural value in the WA rangelands and the risk that they may become environmental weeds. Weeds can occur in many land-use systems including agriculture, horticulture and forestry; however, the focus of this protocol is on the risk that non-indigenous agricultural plants may become …

Cover Cropping To Improve The Sustainability Of Agronomic Production Systems, Ricardo St Aime

All Dissertations

The adoption rate of cover cropping among farmers in the Southeast is low due to the lack of knowledge regarding the suitable cover crop species and their management practices and the concerns of resource depletion for the subsequent cash crop. To generate information addressing the above knowledge gap, the present research was conducted with the following objectives: (1) to determine the optimal planting method for winter cover crops in the upstate of SC and whether it is influenced by the seeding rates (Project-1); (2) to determine suitable winter cover crops for the region based on biomass production, water use efficiency …

Investigating Hops Production In Arkansas To Support Specialty Crop Growth, James Oliver Mcclellan

Graduate Theses and Dissertations

The hop plant (Humulus lupulus L.) is a perennial, climbing species within the Cannabaceae family that produces cones used for brewing. Hops are grown worldwide. In the United States most hops production occurs in the Pacific Northwest, but growth in the craft beer industry is driving efforts for hops production in other U.S. regions. Recommendations on hops cultivar suitability, fertility, and management are needed for the U.S. mid-south region. Objectives of this research on Arkansas-grown hops were to 1) assess the impact of cultivar and fertility rate on plant and cone attributes of six cultivars of Arkansas-grown hops and 2) …

Optimization Techniques For Soil Organic Carbon Prediction Using Mid-Infrared Spectroscopy, Minerva J. Dorantes

Graduate Theses and Dissertations

Resource-efficient techniques for accurate soil carbon estimation are necessary to satisfy the increasing demand for spatiotemporal data. In the last thirty years, mid-infrared (MIR) soil spectroscopy has developed as an accurate, rapid, cost-effective, and non-destructive technique for soil organic carbon (SOC) analysis. In soil spectroscopy, a calibration model relates spectral data to a corresponding measured soil property and is subsequently used to predict this value from new spectral data. Various optimization techniques have been used to improve the statistical performance of calibrations; however, there is little consensus on the conditions that make these techniques effective. The objectives of this research …

Quantification And Machine Learning Based N2o–N And Co2–C Emissions Predictions From A Decomposing Rye Cover Crop, Deepak R. Joshi, David E. Clay, Sharon A. Clay, Janet Moriles-Miller, Aaron L. M. Daigh, Graig Reicks, Shaina Westhoff

Department of Agronomy and Horticulture: Faculty Publications

Cover crops improve soil health and reduce the risk of soil erosion. However, their impact on the carbon dioxide equivalence (CO_2e) is unknown. Therefore, the objective of this 2-yr study was to quantify the effect of cover crop-induced differences in soil moisture, temperature, organic C, and microorganisms on CO_2e, and to develop machine learning algorithms that predict daily N₂O–N and CO₂–C emissions. The prediction models tested were multiple linear regression, partial least square regression, support vector machine, random forest (RF), and artificial neural network. Models’ performance was accessed using R², …

Registration Of Lcs ‘Valiant’ Hard Red Winter Wheat, P. Stephen Baenziger, S. D. Masterson, J. D. Boehm Jr., Vikas Belamkar, M. D. Barnett, Devin J. Rose, Lan Xu, Stephen N. Wegulo, T. Regassa, Amanda Easterly, Cody F Creech, Dipak K. Santra, G. R. Kruger, G. W. Hergert, R. N. Klein, J. Kolmer, J. Kolmer, M.-S. Chen, Gary L. Hein, R. L. Bowden, M. J. Guttieri, G. Bai, El-Basyoni Salah, J. Poland

Department of Agronomy and Horticulture: Faculty Publications

Historically cultivars developed jointly by the University of Nebraska-Lincoln and USDA-ARS wheat (Triticum aestivum L.) improvement project tend to be late and better adapted to the northern Great Plains. LCS ‘Valiant’ (Reg. no. CV-1196, PI 693223; tested as NE10478-1) was released based on the merits of its earliness, agronomic performance, relevant disease resistances, and end-use quality characteristics and its adaptation to the central Great Plains. As such, the line was licensed to Limagrain Cereal Seeds for their ability to market outside of Nebraska. LCS Valiant hard red winter wheat was released in March 2020 by the developing institutions and …

Association Analyses Of Host Genetics, Root-Colonizing Microbes, And Plant Phenotypes Under Different Nitrogen Conditions In Maize, Michael A. Meier, Gen Xu, Martha G. Lopez-Guerrero, Guangyong Li, Christine Smith, Brandi Sigmon, Joshua R. Herr, James R. Alfano, Yufeng Ge, James C. Schnable, Jinliang Yang

Department of Agronomy and Horticulture: Faculty Publications

The root-associated microbiome (rhizobiome) affects plant health, stress tolerance, and nutrient use efficiency. However, it remains unclear to what extent the composition of the rhizobiome is governed by intraspecific variation in host plant genetics in the field and the degree to which host plant selection can reshape the composition of the rhizobiome. Here, we quantify the rhizosphere microbial communities associated with a replicated diversity panel of 230 maize (Zea mays L.) genotypes grown in agronomically relevant conditions under high N (+N) and low N (-N) treatments. We analyze the maize rhizobiome in terms of 150 abundant and consistently reproducible …

Replacing Fallow With Field Pea In Wheat Production Systems Across Western Nebraska, Samuel T. Koeshall, Amanda Easterly, Rodrigo Werle, Strahinja Stepanovic, Cody F. Creech

Department of Agronomy and Horticulture: Faculty Publications

Integration of field pea (Pisum sativum L.) (FP) into dryland cropping systems has increased due to ecological and economic benefits, paired with a growing market for pea-derived products. Challenges exist in the High Plains that limit the integration of crop rotations to replace fallow periods with FP in wheat (Triticum aestivum L.)- based systems. This experiment compares chemical summer fallow to FP in a fallow– wheat rotation at two locations in western Nebraska. Soil water content, soil fertility, N mineralization, FP yield, and subsequent hard red winter wheat (HWW) yields were recorded. Subsequent HWW yields were not different …

Snp Genotyping For Purity Assessment Of A Forage Oat (Avena Sativa L.) Variety From Colombia, Luis Fernando Campuzano-Duque, Diego Bejarano-Garavito, Javier Castillo-Sierra, Daniel Ricardo Torres-Cuesta, Andrés J. Cortés, Matthew Wohlgemuth Blair

Agricultural and Environmental Sciences Faculty Research

Single nucleotide polymorphism (SNP) markers have multiple applications in plant breeding of small grains. They are used for the selection of divergent parents, the identification of genetic variants and marker-assisted selection. However, the use of SNPs in varietal purity assessment is under-reported, especially for multi-line varieties from the public sector. In the case of variety evaluation, these genetic markers are tools for maintaining varietal distinctness, uniformity and stability needed for cultivar release of multi-line or pure-line varieties of inbred crops. The objective of this research was to evaluate the purity and relationships of one original (AV-25) and two multi-line sub-populations …

Non-Destructive Classification And Quality Evaluation Of Proso Millet Cultivars Using Nir Hyperspectral Imaging With Machine Learning, Laruen E. Doyle, Julia R. Loeb, Nader Ekramirad, Dipak K. Santra, Akinbode A. Adedeji

Department of Agronomy and Horticulture: Faculty Publications

Millet is a small-seeded cereal crop with big potential and remarkable characteristics such as high drought resistance, short growing time, low water footprint, and the ability to grow in acidic soil. There is a need to develop nondestructive methods for differentiation and evaluation of the quality attributes of different of proso millet cultivars grown in the U.S. Current methods of cultivar classification are either subjective or destructive, time consuming, not allowing for the whole population to be tested, and requiring trained operators and special equipment. In this study, the feasibility of using near-infrared (NIR) hyperspectral imaging (900-1700 nm) to predict …

Cover Cropping: Sensor-Based Estimations Of Biomass Yield And Nutrient Uptake And Its Impact On Sugarcane Productivity, Hector H. Fajardo Duran

LSU Master's Theses

Sugarcane in Louisiana can be harvested for up to three years from one planting. Soil cultivation along sides of established beds is done for weed control and improve fertilizer use efficiency which increases the risk of soil degradation and yield decline. Planting cover crops (CC) is a soil conservation practice and an effective strategy to improve soil health and nutrient recycling. Limited work has been done on remote sensor-based evaluation of the potential nutrient benefits from cover crops and its effect on nutrient cycling on sugarcane systems. This study was conducted to evaluate the effect of two planting methods (broadcast …

Optimization Of Nozzle, Application Height, And Speed For Uass Pesticide Applications, Trenton Houston

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

Unmanned aerial spray systems (UASS) applications have the potential to be efficient pesticide application platforms under conditions that are not accessible or fit for typical pesticide application equipment. Although this type of application is still under development in the United States, UASS pesticide applications are common in Asia, as they have replaced backpack sprayers. There is limited literature on the optimization of UASS applications and many parameters need to be investigated to identify the best combination of application variables such as flight height, flight speed, and nozzle selection. The objectives were to identify the deposition patterns of a four rotor …

Arkansas Corn And Grain Sorghum Research Studies 2021, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2021 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, and insect management; economics; sustainability; irrigation; post-harvest drying; soil fertility; mycotoxins; cover crop management; and research verification program results. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

Neuropilin-2 Regulates Androgen-Receptor Transcriptional Activity In Advanced Prostate Cancer, Samikshan Dutta, Navatha Shree Polavaram, Ridwan Islam, Sreyashi Bhattacharya, Sanika Bodas, Thomas Mayr, Sohini Roy, Sophie Alvarez, Marieta I. Toma, Anza Darehshouri, Angelika Borkowetz, Stefanie Conrad, Susanne Fuessel, Manfred Wirth, Gustavo B. Baretton, Paramita Ghosh, Kenneth J. Pienta, David L. Klinkebiel, Surinder K. Batra, Michael H. Muders, Kaustubh Datta

Department of Agronomy and Horticulture: Faculty Publications

Aberrant transcriptional activity of androgen receptor (AR) is one of the dominant mechanisms for developing of castration-resistant prostate cancer (CRPC). Analyzing AR-transcriptional complex related to CRPC is therefore important towards understanding the mechanism of therapy-resistance. While studying its mechanism, we observed that a transmembrane protein called neuropilin-2 (NRP2) plays a contributory role in forming a novel AR-transcriptional complex containing nuclear pore proteins. Using immunogold electron microscopy, high-resolution confocal microscopy, chromatin immunoprecipitation, proteomics, and other biochemical techniques, we delineated the molecular mechanism of how a specific splice variant of NRP2 becomes sumoylated upon ligand stimulation and translocates to the inner nuclear …

Unraveling The Mechanism Of Resistance In A Glufosinate-Resistant Palmer Amaranth (Amaranthus Palmeri) Accession, Pamela Carvalho-Moore, Jason K. Norsworthy, Fidel Gonzalez-Torralva, Jeong-In Hwang, Jinesh D. Patel, L. Tom Barber, Thomas R. Butts, J. Scott Mcelroy

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Glufosinate resistance in Palmer amaranth (Amaranthus palmeri S. Watson) was recently detected in three accessions from Arkansas, USA. Amaranthus palmeri is the first and only broadleaf weed species resistant to this herbicide, and the resistance mechanism is still unclear. A previous study characterized the glufosinate resistance level in the accessions from Arkansas. A highly glufosinate-resistant accession was further used to investigate the mechanism conferring glufosinate resistance in A. palmeri. Experiments were designed to sequence the herbicide target enzyme cytosolic and chloroplastic glutamine synthetase isoforms (GS1 and GS2, respectively) and quantify copy number and expression. Absorption, translocation, and metabolism of glufosinate …

Simulating The Impact Of Crop–Livestock Interaction On Crop Performance Using Dssat, Teerath Rai, Sandeep Kumar, Thandiwe Nleya, Gerrit Hoogenboom

Agronomy, Horticulture and Plant Science Faculty Publications

An integrated crop–livestock system (ICL) can help with enhancing soil quality and crop productivity, ultimately increasing farm income. Field experiments that evalu- ated the impact of cover crops (CCs) and grazing on crop productivity have shown mixed results primarily because of a relatively short duration of the crop–livestock system. Dynamic crop models can help to simulate the long-term impact of soils and crop management on crop yield. The objectives of the current study were to develop a simple simulation methodology for crop–livestock interaction using the Decision Support System for Agrotechnology Transfer (DSSAT) and to evaluate the perfor- mance of CC …

Pestfacts Wa Issue 10 - July 2022, Saleh Adnan, Benjamin S. Congdon, Alan Lord

PestFacts WA

PestFacts WA Issue 10 - July 2022 contents:

• Russian wheat aphids found at Geraldton
• Turnip yellows virus detected n canola in Albany port zone
• Meet PestFacts WA team member – Alan Lord

Increased Signal-To-Noise Ratios Within Experimental Field Trials By Regressing Spatially Distributed Soil Properties As Principal Components, Jeffrey C. Berry, Mingsheng Qi, Balasaheb V. Sonawane, Amy Sheflin, Asaph Cousins, Jessica Prenni, Daniel P. Schachtman, Peng Liu, Rebecca S. Bart

Department of Agronomy and Horticulture: Faculty Publications

Environmental variability poses a major challenge to any field study. Researchers attempt to mitigate this challenge through replication. Thus, the ability to detect experimental signals is deter-mined by the degree of replication and the amount of environmental variation, noise, within the experimental system. A major source of noise in field studies comes from the natural heterogeneity of soil properties which create microtreatments throughout the field. In addition, the variation within different soil properties is often nonrandomly distributed across a field. We explore this challenge through a sorghum field trial dataset with accompanying plant, microbiome, and soil property data. Diverse sorghum …

Expression Of Atwri1 And Atdgat1 During Soybean Embryo Development Influences Oil And Carbohydrate Metabolism, Cintia Lucía Arias, Truyen Quach, Tu Huynh, Hanh Nguyen, Ademar Moretti, Yu Shi, Ming Guo, Amira Rasoul, Kyujung Van, Leah Mchale, Thomas E. Clemente, Ana Paula Alonso, Chi Zhang

Department of Agronomy and Horticulture: Faculty Publications

Soybean oil is one of the most consumed vegetable oils worldwide. Genetic improvement of its concentration in seeds has been historically pursued due to its direct association with its market value. Engineering attempts aiming to increase soybean seed oil presented different degrees of success that varied with the genetic design and the specific variety considered. Understanding the embryo’s responses to the genetic modifications introduced, is a critical step to successful approaches. In this work, the metabolic and transcriptional responses to AtWRI1 and AtDGAT1 expression in soybean seeds were evaluated. AtWRI1 is a master regulator of fatty acid (FA) biosynthesis, and …

Critical P, K And S Concentrations In Soil And Shoot Samples For Optimal Tedera Productivity And Nodulation, Daniel Real, Richard G. Bennett, Nazanin K. Nazeri, David M. Weaver

Grain and Other Field Crops Research Articles

Tedera is a forage legume that can provide out-of-season green feed in Mediterranean climates. To date, growers have had no comprehensive soil nutrition guidelines to optimise tedera production. We undertook field and glasshouse studies to understand tedera’s macronutrient requirements. Three field experiments were sown with tedera cv. Lanza® at Cunderdin, Dandaragan and Three Springs in Western Australia. These experiments evaluated seven levels of phosphorus (P) (0–30 kg ha−1) and potassium (K) (0–80 kg ha−1) and two combined treatments with P and K. Glasshouse pot experiments were conducted using tedera cultivars Lanza® and Palma and lucerne cultivar SARDI Grazer. Ten concentrations …

Identification Of Putative Snp Markers Associated With Resistance To Egyptian Loose Smut Race(S) In Spring Barley, Kamal A.M. Abo-Elyousr, Amira M.I. Mourad, P. Stephen Baenziger, Abdelaal H.A. Shehata, Peter E. Eckstein, Aaron D. Beattie, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Loose smut (LS) disease is a serious problem that affects barley yield. Breeding of resistant cultivars and identifying new genes controlling LS has received very little attention. Therefore, it is important to understand the genetic basis of LS control in order to genetically improve LS resistance. To address this challenge, a set of 57 highly diverse barley genotypes were inoculated with Egyptian loose smut race(s) and the infected seeds/plants were evaluated in two growing seasons. Loose smut resistance (%) was scored on each genotype. High genetic variation was found among all tested genotypes indicating considerable differences in LS resistance that …

Determination Of Crop Coefficient Of Hybrid Wheat Under Arid Climate: A Pot Study, Saba Wajid, Muhammad Imran, Hafiz Shahzad Ahmad, Muhammad Zeeshan Gulzar, Tanveer Ul Haq, Abdul Ghaffar, Sarmad Frogh Arshad, Zulqurnain Khan, Kashif Bashir, Hasan Riaz

Journal of Bioresource Management

Climate change increases vulnerabilities for crop productivity in Pakistan. Water crises are increasing with an increase in temperature and change in precipitation patterns due to climate change which ultimately imposed a threat to the food security of the country. Water is indispensable for all plants to complete life cycle as the unavailability of water at critical growth stages drastically affects the development of the plant. The present pot study was conducted for the estimation of crop coefficient of hybrid wheat for irrigation scheduling at Muhammad Nawaz Shareef University of Agriculture, Multan during two growing seasons 2018-19 and 2019-20. In this …

Improving Growth And Yield Of Sunflower With Integrated Use Of Compost And Pgpr (Variovorax Paradoxus) With Different Levels Of N-Chemical Fertilizer, Muhammad Imran, Muhammad Javed Akhtar, Sarmad Frogh Arshad, Muhammad Ashfaq, Muhammad Zeeshan Gulzar, Hafiz Shahzad Ahmad, Kashif Bashir, Zulqurnain Khan, Hasan Riaz, Tanveer Ul Haq

Journal of Bioresource Management

Plant growth-promoting rhizobacteria (PGPRs) stimulate plant growth through their ability, to increasing the root length and growth, by asymbiotic nitrogen fixation, by producing siderophores, solubilization of mineral phosphates and mineralization of other nutrients. Organic waste material of fruits and vegetables was collected and composted in a locally fabricated composting unit. A pot trial was conducted to study the effectiveness of compost and PGPR (Variovorax paradoxus) with recommended rate of PK and with different rates of N fertilizer i.e. 50 %, 75 % and 100 %, on growth and yield of sunflower. Results showed that the integrated use of …

Legacy Lead In Urban Garden Soils: Communicating Risk And Limiting Exposure, Anna Paltseva, Zhongqi Cheng, Murray Mcbride, Maha Deeb, Sara Perl Egendorf, Peter M. Groffman

Advanced Science Research Center

Lead (Pb) exposure has long been recognized as a hazard to human health. Urban garden soils often contain elevated levels of Pb, mainly from legacy sources, which is a main barrier for urban gardening. The capacity of gardeners to access, understand, and act on scientific data related to soil contamination is also variable. This synthesis paper briefly summarizes the current scientific knowledge on soil Pb in urban gardens. Our objective is to produce clear recommendations about assessing actual risks and limiting exposure. First, we synthesize the nature and extent of soil contamination with Pb, and then describe how the bioavailability …

Sorghum Association Panel Whole-Genome Sequencing Establishes Cornerstone Resource For Dissecting Genomic Diversity, J. Lucas Boatwright, Sirjan Sapkota, Hongyu Jin, James C. Schnable, Zachary Brenton, Richard Boyles, Stephen Kresovich

Department of Agronomy and Horticulture: Faculty Publications

Association mapping panels represent foundational resources for understanding the genetic basis of phenotypic diversity and serve to advance plant breeding by exploring genetic variation across diverse accessions. We report the whole-genome sequencing (WGS) of 400 sorghum (Sorghum bicolor (L.) Moench) accessions from the Sorghum Association Panel (SAP) at an average coverage of 38× (25–72×), enabling the development of a high-density genomic marker set of 43 983 694 variants including single-nucleotide polymorphisms (approximately 38 million), insertions/deletions (indels) (approximately 5 million), and copy number variants (CNVs) (approximately 170 000). We observe slightly more deletions among indels and a much higher prevalence …

Water Quality, Carrier Volume And Droplet Size Effects On Herbicide Efficacy And Drift Potential, Barbara Houston

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

Herbicide performance is directly related to the amount of active ingredient that has been deposited on the plant. Hence, spray solution characteristics and application parameters are crucial in determining the efficacy of an herbicide application. To maximize the effectiveness of chemical control, methods to deliver full chemical dose must be utilized: allowing the active ingredient to be readily absorbed once added to the carrier and mitigating off-target movement and low herbicide doses. Water is the most frequently used carrier in herbicide applications. Chemical parameters, such as water hardness and pH, can have a critical role in herbicide performance. It is …

Recombination Hotspots In Soybean [Glycine Max (L.) Merr.], Samantha J. Mcconaughy

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

Recombination allows for the exchange of genetic material between two parents which plant breeders exploit to make new and improved varieties. This recombination is not distributed evenly across the chromosome. In crops, it mostly occurs in the euchromatic regions of the genome and even then, recombination is focused into recombination hotspots flanked by recombination cold spots. Understanding the distribution of these hotspots along with the sequence motifs associated with them may lead to methods that enable breeders to better exploit recombination in breeding.

In chapter 1 background information on recombination, recombination hotspots detection methods, landscape of recombination (describe recombination patterns …