Horticulture Commons^™

Hop Cone Drying For The Small Grower: Temperature And Airflow Considerations, Stacy A. Adams, David M. Mabie, Michael F. Kocher, David Jones

Department of Agronomy and Horticulture: Faculty Publications

Small hop growers without nearby processors for cone stripping and drying must attempt to do so on their own farm. Challenges exist for self-built drying systems, including drying capacity, processing speed, airflow direction, and maintaining quality during drying. Research-based recommendations are given for optimal temperature, sizing of drying vessel, maximum cone depth, and influences associated with airflow on processing uniformity and cone quality are presented.

2020-2021 Field Seasons Of Maize Gxe Project Within The Genomes To Fields Initiative, Dayane Cristina Lima, Alejandro Castro Aviles, Ryan Timothy Alpers, Alden Perkins, Dylan L. Schoemaker, Martin Costa, Kathryn J. Michel, Shawn Kaeppler, David Ertl, Maria Cinta Romay, Joseph L. Gage, James Holland, Timothy Beissinger, Martin Bohn, Edward Buckler, Jode Edwards, Sherry Flint-Garcia, Michael A. Gore, Candice N. Hirsch, Joseph E. Knoll, John Mckay, Richard Minyo, Seth C. Murray, James Schnable, Rajandeep S. Sekhon, Maninder P. Singh, Erin E. Sparks, Peter Thomison, Addie Thompson, Mitchell Tuinstra, Jason Wallace, Jacob D. Washburn, Teclemariam Weldekidan, Wenwei Xu, Natalia De Leon

Department of Agronomy and Horticulture: Faculty Publications

Objectives: This release note describes the Maize GxE project datasets within the Genomes to Fields (G2F) Initiative. The Maize GxE project aims to understand genotype by environment (GxE) interactions and use the information collected to improve resource allocation efficiency and increase genotype predictability and stability, particularly in scenarios of variable environmental patterns. Hybrids and inbreds are evaluated across multiple environments and phenotypic, genotypic, environmental, and metadata information are made publicly available. Data description: The datasets include phenotypic data of the hybrids and inbreds evaluated in 30 locations across the US and one location in Germany in 2020 and 2021, soil …

Vulnerabilities Of Greater Prairie Chicken And Tier 1 At-Risk Species In Nebraska Caused By Grassland Transition To Woody Dominance, Robert Peterson

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

Woody plant encroachment is a global threat and has been transitioning grasslands to woody dominance at a biome scale. This threat is present in the Great Plains grassland biome which is currently experiencing grassland biome collapse as the alternative woody biome advances northwest. Nebraska, which contains the most intact temperate grassland in the world, is currently at the front lines of this large-scale transition making this state’s management decisions vital for the remaining grasslands and the species which rely on these ecosystems. In this study, we assess the vulnerability of Greater Prairie Chicken and Tier 1 at-risk species in Nebraska …

Does Selection For Seedling Tiller Number In Perennial Biomass Feedstocks Translate To Yield And Quality Improvements In Mature Swards?, Robert B. Mitchell, Kenneth P. Vogel, Susan Tunnell, James Stubbendieck

Department of Agronomy and Horticulture: Faculty Publications

Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bioenergy or forage. In previously reported research, breeding for single large tillers (ST) or multiple tillers (MT, ≥3) six weeks after planting for two generations in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) base populations produced ST and MT populations that differed significantly for seedling and mature plant traits including biomass yield in spaced planted nurseries. Our objective was to evaluate these ST and MT populations in sward …

Genetic Analysis Of Basal Stalk Rot Resistance Introgressed From Wild Helianthus Petiolaris Into Cultivated Sunflower (Helianthus Annuus L.) Using An Advanced Backcross Population, Zahirul I. Talukder, William Underwood, Christopher G. Misar, Xuehui Li, Gerald J. Seiler, Xiwen Cai, Lili Qi

Department of Agronomy and Horticulture: Faculty Publications

Introduction: Sclerotinia sclerotiorum is a serious pathogen causing severe basal stalk rot (BSR) disease on cultivated sunflower (Helianthus annuus L.) that leads to significant yield losses due to insufficient resistance. The wild annual sunflower species H. petiolaris, commonly known as prairie sunflower is known for its resistance against this pathogen. Sunflower resistance to BSR is quantitative and determined by many genes with small effects on the resistance phenotype. The objective of this study was to identify loci governing BSR resistance derived from H. petiolaris using a quantitative trait loci (QTL) mapping approach.

Methods: BSR …

Effects Of Rootstock And Location On Open Field ‘Bhn 589’ And ‘Nebraska Wedding’ Grafted Tomato Yield, Raihanah H. Shonerd, Ashley A. Thompson, Samuel E. Wortman

Department of Agronomy and Horticulture: Faculty Publications

Grafted tomato (Solanum lycopersicum) production is popular, particularly in high tunnels, because grafted plants can mitigate soilborne disease incidence in highly infested soils and increase water and nutrient use efficiency and crop yield and quality. However, these potential benefits are not as well documented in open field production systems with less disease pressure. The objective of this study was to quantify the effect of tomato grafting on fruit yield, number, and size across 2 years (2018 and 2019) and three diverse open-field production environments in Nebraska (Lincoln, North Platte, and Dwight). At each location, a scion from one …

Evaluation Of Land Preparation Methods For Soil Stabilization, Revegetation, And Renewed Productivity In Semi-Arid Climates, Jarrett Lardy, North Dakota State University, Miranda Meehan, Aaron L. M. Daigh, James Staricka, Nathan Derby

Department of Agronomy and Horticulture: Faculty Publications

In the Williston Basin, land-preparation treatments have not been compared in side-by-side trials to evaluate performance for parameters such as runoff, erosion, and vegetation establishment. Thus, four treatments of wheat-straw crimping, land imprinting, wood-fiber hydromulch, and the combination of land imprinting and hydromulch were evaluated against a bare soil control in a replicated and randomized completed block field experiment near Williston, ND. Rainfall simulations were performed in September 2020 and June 2021 to examine the effectiveness of the treatments to reduce runoff and sediment losses. Vegetation establishment was also evaluated in August 2021. The wheat straw treatment reduced the equivalent …

Deleterious Mutations Predicted In The Sorghum (Sorghum Bicolor) Maturity (Ma) And Dwarf (Dw) Genes From Whole‑Genome Resequencing, Nathan P. Grant, John J. Toy, Deanna L. Funnell, Scott E. Sattler

Department of Agronomy and Horticulture: Faculty Publications

In sorghum [Sorghum bicolor (L.) Moench] the Maturity (Ma1, Ma2, Ma3, Ma4, Ma5, Ma6) and Dwarf (Dw1, Dw2, Dw3, Dw4) loci, encode genes controlling flowering time and plant height, respectively, which are critical for designing sorghum ideotypes for a maturity timeframe and a harvest method. Publicly available whole-genome resequencing data from 860 sorghum accessions was analyzed in silico to identify genomic variants at 8 of these loci (Ma1, Ma2, Ma3, Ma5, Ma6, Dw1, Dw2, Dw3) to identify novel loss …

Did Cover Crop Or Animal Manure Ameliorate Corn Residue Removal Effects On Soil Mechanical Properties After 10 Years?, Hans W. Klopp, Humberto Blanco-Canqui, Michael Sindelar, Virginia L. Jin, Marty R. Schmer, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Crop residue removal may negatively affect soil mechanical properties, which are key components of soil quality. To evaluate potential long-term effects, we assessed the 10-yr impact of corn (Zea mays L.) residue removal (59 % of non-grain biomass annually) on surface soil mechanical properties (0–20 cm). We also evaluated whether adding carbon (C) amendments, such as using a winter rye (Secale cereale L.) cover crop or surface-applying cattle manure (24 Mg ha− 1 biannually) can ameliorate the effects of crop residue removal. This long-term study was under irrigated no-till continuous corn on a silt loam soil in south-central …

Is Climate Change Causing The Range Contraction Of Cape Rock-Jumpers (Chaetops Frenatus)?, Gregory D. Duckworth, Raquel A. Garcia, Rheinhardt Scholtz, Res Altwegg

Department of Agronomy and Horticulture: Faculty Publications

Species distribution models often suggest strong links between climate and species' distribution boundaries and project large distribution shifts in response to climate change. However, attributing distribution shifts to climate change requires more than correlative models. One idea is to examine correlates of the processes that cause distribution shifts, namely colonization and local extinction, by using dynamic occupancy models. The Cape Rock-jumper (Chaetops frenatus) has disappeared over most of its distribution where temperatures are the highest. We used dynamic occupancy models to analyse Cape Rock-jumper distribution with respect to climate (mean temperature and precipitation over the warmest annual quarter), …

Dicamba Off-Target Movement From Applications On Soybeans At Two Growth Stages, Greg R. Kruger, Guilherme S. Alves, Kasey Schroeder, Jeffrey A. Golus, Daniel B. Reynolds, Darrin M. Dodds, Ashli E. Brown, Bradley K. Fritz, Wesley C. Hoffmann

Department of Agronomy and Horticulture: Faculty Publications

The objective of this study was to evaluate dicamba off-target movement during and after applications over soybean at two growth stages. Dicamba-tolerant soybean [Glycine max (L.) Merr.] at V3 and R1 growth stages in Nebraska and Mississippi fields were treated with diglycolamine salt of dicamba (560 g ae ha⁻¹), potassium salt of glyphosate (1260 g ae ha⁻¹), and a drift-reducing adjuvant (0.5% v v⁻¹). Filter papers positioned outside the sprayed area were used to determine primary movement and air samplers positioned at the center of sprayed area were used to calculate dicamba flux …

A Follow-Up Survey To Assess Stakeholders’ Perspectives On Weed Management Challenges And Current Practices In Nebraska, Usa, Shawn T. Mcdonald, Debalin Sarangi, Jennifer M. Rees, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Stakeholders across the state of Nebraska, USA, were surveyed in 2019–2020 to assess problem weeds and weed management practices in agronomic crops. A total of 420 complete responses were obtained across four Nebraska districts (Northeast, Panhandle, Southeast, and West Central). Accumulated across the state, 65.5% of farmed or scouted crop ground in Nebraska was under no-till production, with the major crops being corn and soybean representing 39.3% and 30.7% of agronomic crop production area, respectively. Palmer amaranth, horseweed, waterhemp, kochia, and giant ragweed were ranked the most problematic weeds. In a 2014–2015 survey, Palmer amaranth was the sixth most problematic …

The Evolving Definition Of Plant Cell Type, Sahand Amini, Jeffrey J. Doyle, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

In 1665 Robert Hooke, looking at cork through his microscope, discovered that plants are composed of elementary structures he named “cells”. Variation in the expression of a single genome in a complex eukaryotic organism guides the initiation, maturation, physiology, and biochemistry of cells with different shapes and sizes, playing different structural and functional roles in space and time. How many kinds of cells—”cell types”— an organism possesses of course depends on the organism’s cellular complexity, but the plasticity within a cell type fuels the emergence of the concept of cell state (Figure 1). The transition between cell states is driven …

Shortening Harvest Interval, Reaping Benefits? A Study On Harvest Practices In Oil Palm Smallholder Farming Systems In Indonesia, Rosanne E. De Vos, Lisa Nurfalah, Fatima A. Tenorio, Ya Li Lim, Juan Pablo Monzon, Christopher R. Donough, Hendra Sugianto, Asri A. Dwiyahreni, Nurul L. Winarni, Nadia Mulani, Gilang Ramadhan, Muhammad Ali Imran, Antonius P. Tito, Pandu Sulistiawan, Muhammad Khoirul, Rana Farrasati, Iput Pradiko, Patricio Grassini, Maja Slingerland

Department of Agronomy and Horticulture: Faculty Publications

CONTEXT: Smallholders are responsible for a large share of global palm oil production. Yet, in Indonesia, the main palm oil producing country, smallholders’ yields remain low. Better management practices, including short harvest interval (HI, the number of days between two harvest rounds), could help to raise smallholder yields. However, at present, HI is long in smallholder fields and the drivers underlying this phenomenon are poorly understood.

OBJECTIVE: We explored agronomic, socio-economic, and institutional factors that underlie harvesting practices in independent oil palm smallholder farming systems in Indonesia to assess scope for sustainable intensification through shorter HI and reduced …

Exotic Herbivores And Fire Energy Drive Standing Herbaceous Biomass But Do Not Alter Compositional Patterns In A Semiarid Savanna Ecosystem, Virginia D. Preiss, Carissa L. Wonkka, Devan A. Mcgranahan, Alexandra G. Lodge, Matthew B. Dickinson, Kathleen L. Kavanagh, Heath D. Starns, Douglas R. Tolleson, Morgan L. Treadwell, Dirac L. Twidwell Jr, William E. Rogers

Department of Agronomy and Horticulture: Faculty Publications

Questions: Fire regime alterations are pushing open ecosystems worldwide past tipping points where alternative steady states characterized by woody dominance prevail. This reduces the frequency and intensity of surface fires, further limiting their effectiveness for controlling cover of woody plants. In addition, grazing pressure (exotic or native grazers) can reinforce woody encroachment by potentially reducing fine-fuel loads. We investigated the effects of different fire energies on the herbaceous plant community, together with mammalian wildlife herbivory (exotic and native combined) exclusion, to inform best management practices.

Location: Texas semi-arid savanna, southern Great Plains, USA.

Methods: We conducted an …

Targeted Sequencing Of The Panicum Miliaceum Gene Space And Genotyping Of Variant Sites From Population Genetics Studies, Combined In A Single Assay, As A Tool For Broomcorn Millet Assisted Breeding, Gabriele Magris, Serena Foria, Silvano Ciani, Dipak K. Santra, Ombretta Polenghi, Virna Cerne, Michele Morgante, Gabriele Di Gaspero

Department of Agronomy and Horticulture: Faculty Publications

Broomcorn millet (Panicum miliaceum L.) is a prehistorical cereal, today cultivated as a minor crop with low yields but with a renewed interest for its high water use effciency and gluten-free grains. To reverse the downward trend in broomcorn millet cultivation, the crop needs genetic improvement and creation of novel genetic variation to increase productivity. In order to facilitate genomics-assisted breeding, we designed a reduced representation genome-sequencing assay that investigates 1.8% of the nuclear DNA in a targeted and reproducible way, with an intensity of genomic sampling that is a direct function of local recombination rate. We used this …

Indigenous Lakadong Turmeric Of Meghalaya And Its Future Prospects, Manjit Kumar Ray, Dipak K. Santra, Piyush Kumar Mishra, Saurav Das

Department of Agronomy and Horticulture: Faculty Publications

Turmeric (Curcuma longa) has long been used in traditional Indian medicine. India accounts for 80% of total global turmeric production. Lakadong turmeric gets its name from the tiny village of Lakadong, which is located in the foothills of the Jaintia Hills in Meghalaya, India. It is known for having a high curcumin content of more than 7%, as opposed to 2 - 4% in regular varieties. The tribes of this region brought Lakadong turmeric from the forest and domesticated it for medicinal purposes centuries ago. Growth in local coal industries and a gradual decline in the market have …

Effect Of Cutting Management On The Forage Production And Quality Of Tepary Bean (Phaseolus Acutifolius A. Gray), Travis W. Witt, Brian K. Northup, Timothy G. Porch, Santos Barrera, Carlos A. Urrea

Department of Agronomy and Horticulture: Faculty Publications

Tepary bean (Phaseolus acutifolius A. Gray) is an underutilized drought tolerant annual legume, originating from the Sonoran Desert, that may be a beneficial forage/hay for beef cattle in the Southern Great Plains of the US (SGP). The SGP has erratic rainfall and periods of intermittent drought exacerbated by high summer temperatures. In 2020 and 2021, a split-plot design was used to evaluate 13 genotypes of tepary bean and a forage soybean (control) at El Reno, OK, USA to compare production of plant biomass and forage nutritive value parameters under seven harvest regimes. Genotypes were used as the main plot …

Lunchbox Hydroponics, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Growing plants with hydroponics is less complicated than it may appear when the fundamentals of the system are understood. This publication provides instruction on the construction of a simple hydroponic prototype suitable for school or youth education programs. The fundamentals of hydroponics, basic design of a solution system, seed starting, creating a nutrient solution, and plant care are explored through this engaging project. This prototype can successfully be used to grow small edible and herb plants in the classroom or at home.

Method Developments To Identify Loci And Selection Patterns Associated With Genotype By Environment Interactions In Soybean, Mary M. Happ

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

For many complex traits such as grain yield, genotype by environment (GxE) interactions are a prevalent source of phenotypic variation. Exploring the capacity of different methodologies to help describe and quantify the GxE interaction landscape for grain yield is an important step in informing plant breeders what the most viable strategies for management and exploitation of GxE may be. In this endeavor, we compared the results from multiple genome wide association studies (GWAS) that used either stability estimators as a phenotype to capture GxE variance, or directly mapped GxE in a mixed model for yield. Leading into this study, a …

Increasing Rye Cover Crop Biomass Production After Corn Residue Removal To Balance Economics And Soil Health, Sabrina J. Ruis, Humberto Blanco-Canqui, Paul J. Jasa, Glen Slater, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Low or variable cover crop (CC) biomass production could limit CC benefits. Longer CC growing periods via late termination could increase CC benefits, especially under limited crop residue return. We studied whether early (2–3 wk before planting)- or late (at planting)-terminated winter rye (Secale cereale L.) CC maintains soil properties, crop yields, and farm income under 0%, 25%, 50%, 75%, and 100% corn (Zea mays L.) residue removal in rainfed and irrigated no-till in the U.S. Great Plains after 6 yr. Early-terminated CCs produced < 1 Mg ha^-1 of biomass while late-terminated CCs averaged 1.6 Mg ha^-1 at the rainfed …

Soybean Tolerance To Ultra-Low Doses Of Dicamba: Hormesis Or Not, Luka Milosevic, O. Adewale Osipitan, Jon E. Scott, Stevan Z. Knezevic

Department of Agronomy and Horticulture: Faculty Publications

The widespread use of dicamba across the soybean growing regions of the United States resulted in increased off-target movement of this herbicide to susceptible vegetations. There are speculations that a drift of sublethal (ultra-low) doses of dicamba can enhance soybean growth and yield through a phenomenon called hormesis. Field studies were conducted during 2018 and 2019 to determine whether soybean growth and yield can be enhanced with ultra-low doses (0.0112–56 g ae ha^-1) of dicamba, applied at three growth stages (V2, R1 and R2). There was no evidence that the ultra-low doses of dicamba (0.0112–56 g ae ha …

Unraveling Prevalence And Effects Of Deleterious Mutations In Maize Elite Lines Across Decades Of Modern Breeding, Shichao Sun, Baobao Wang, Changyu Li, Gen Xu, Jinliang Yang, Matthew B. Hufford, Jeffrey Ross-Ibarra, Haiyang Wang, Li Wang

Department of Agronomy and Horticulture: Faculty Publications

Future breeding is likely to involve the detection and removal of deleterious alleles, which are mutations that negatively affect crop fitness. However, little is known about the prevalence of such mutations and their effects on phenotypic traits in the context of modern crop breeding. To address this, we examined the number and frequency of deleterious mutations in 350 elite maize inbred lines developed over the past few decades in China and the United States. Our findings reveal an accumulation of weakly deleterious mutations and a decrease in strongly deleterious mutations, indicating the dominant effects of genetic drift and purifying selection …

Genomes To Fields 2022 Maize Genotype By Environment Prediction Competition, Dayane Cristina Lima, Jacob D. Washburn, José Ignacio Varela, Qiuyue Chen, Joseph L. Gage, Maria Cinta Romay, James Holland, David Ertl, Marco Lopez-Cruz, Fernando M. Aguate, Gustavo De Los Campos, Shawn Kaeppler, Timothy Beissinger, Martin Bohn, Edward Buckler, Jode Edwards, Sherry Flint-Garcia, Michael A. Gore, Candice N. Hirsch, Joseph E. Knoll, John Mckay, Richard Minyo, Seth C. Murray, Osler A. Ortez, James C. Schnable, Rajandeep S. Sekhon, Maninder P. Singh, Erin E. Sparks, Addie Thompson, Mitchell Tuinstra, Jason Wallace, Teclemariam Weldekidan, Wenwei Xu, Natalia De Leon

Department of Agronomy and Horticulture: Faculty Publications

Objectives The Genomes to Fields (G2F) 2022 Maize Genotype by Environment (GxE) Prediction Competition aimed to develop models for predicting grain yield for the 2022 Maize GxE project field trials, leveraging the datasets previously generated by this project and other publicly available data.

Data description This resource used data from the Maize GxE project within the G2F Initiative [1]. The dataset included phenotypic and genotypic data of the hybrids evaluated in 45 locations from 2014 to 2022. Also, soil, weather, environmental covariates data and metadata information for all environments (combination of year and location). Competitors also had access to ReadMe …

Role Of Biotechnology In Creating Sustainable Agriculture, Saurav Das, Manjit Kumar Ray, Dinesh Panday, Piyush Kumar Mishra

Department of Agronomy and Horticulture: Faculty Publications

This narrative review paper discusses the role of biotechnology in the development of sustainable agriculture. The paper begins by defning sustanability and highlights the importance of biotechnology in establishing sustainable agriculture. Sustainable agriculture is an approach that prioritizes meeting current food and fiber production needs while conserving and enhancing natural resources for future generations. To achieve agricultural sustainability, it is necessary to strike a balance between economic viability, environmental stewardship, and social responsibility. This can be difficult, especially in the face of biotic and abiotic stresses such as pests, diseases, climate change, soil degradation, and water depletion. The prevalence of …

Molecular Identification Of Oomycete Species Associated With Woody Plants In Louisiana And Survey Of Oomycete Species Associated With Live Oak Trees Planted On The Louisiana State University Campus, Hamilton Crockett

LSU Master's Theses

Three Oomycetes genera, Phytophthora, Phytopythium and Pythium, contain many important plant pathogens. Historically, Phytophthora infestans, responsible for the great Irish potato famine, and Phytophthora ramorum, causal agent of sudden oak death disease, are the two better-known high impact pathogens. The LSU AgCenter Plant Diagnostic Center (PDC) has been isolating putative Phytophthora and related species from combined root and soil samples collected from various woody ornamentals and trees for over a decade. In August of 2016, Louisiana received torrential rains, which resulted in historic flooding in several southern parishes. During subsequent years, the PDC staff isolated a …

Classim: A Relational Database Driven Crop Model Interface, Dennis Timlin, David Fleisher, Maura Maura, Kirsten Paff, Wenguang Sun, Sahila Beegum, Sanai Li, Zhuangji Wang, Vangimalla Reddy

Department of Agronomy and Horticulture: Faculty Publications

Crop models are valuable tools for examining the interactions of cultivar characteristics, environment, and management practices, and how they affect crop growth and development. The difficulty in finding all the data needed to set up a simulation can often deter potential users from utilizing a crop model. Model interfaces are necessary to make these complex tools accessible to end-users who may lack the expertise needed to work with the models directly, but who would benefit from the information generated by the models. As crop models vary in terms of input and output structures, there is no one universally compatible interface, …

Tillage, Green Manuring And Crop Residue Management Impacts On Crop Productivity, Potassium Use Efficiency And Potassium Fractions Under Rice-Wheat System, Sandeep Sharma, Pritpal Singh, Hayssam M. Ali, Manzer Hussain Siddiqui, Javed Iqbal

Department of Agronomy and Horticulture: Faculty Publications

The conventional crop production practices including intensive tillage and open field crop residue burning in world’ largest rice-wheat system (RWS) are adversely affecting crop productivity besides deteriorating natural resources and ecosystems’ sustainability. In order to improve system productivity, potassium (K) use efficiency and apparent K balance, adoption of conservation tillage in a RWS with residue management is considered highly effective. We therefore, studied the effect of wheat straw retention and green manure (GM) in rice (main plot treatment), and tillage and rice residue management in subsequent wheat (sub-plot treatments) on crop productivity, K use efficiency and its transformation amongst different …

Conversion Of Native Grassland To Coniferous Forests Decreased Stocks Of Soil Organic Carbon And Microbial Biomass, Lidong Li, Elnaz Hosseiniaghdam, Rhae A. Drijber, Elizabeth Jeske, Tala Awada, J. Hiller, Michael Kaiser

Department of Agronomy and Horticulture: Faculty Publications

Aims Encroachment of woody species into grasslands is a global phenomenon that affects ecosystem services, including soil organic carbon (SOC) storage and microbial community structure. We determined stocks of SOC and soil microbial biomass as affected by conversion of grasslands to coniferous forests.

Methods We examined SOC and soil δ¹³C signatures under three vegetation covers: native grasslands, eastern redcedar (Juniperus virginiana), and ponderosa pine (Pinus ponderosa), at six soil depths (0 − 10, 10 − 30, 30 − 100, 100 − 170, 170 − 240, 240 − 300 cm). Fatty acid methyl esters (FAMEs) …

First Things First: Widespread Nutrient Deficiencies Limit Yields In Smallholder Oil Palm Fields, Hendra Sugianto, Juan Pablo Monzon, Iput Pradiko, Fatima A. Tenorio, Ya Li Lim, Christopher R. Donough, Sunawan, Suroso Rahutomo, Fahmuddin Agus, James Cock, Joni Amsar, Rana Farrasati, Ridho Iskandar, Juan I. Rattalino Edreira, Shofia Saleh, Heri Santoso, Antonius P. Tito, Nadib Ulfaria, Maja A. Slingerland, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

CONTEXT: Indonesia is the most important oil palm producing country. Nearly 40% of planted area is managed by smallholders, with yields well below the potential. Efforts to increase productivity have focused on the source of planting material, with little attention paid to plant nutrition.

OBJECTIVE: To assess the degree to which current productivity in smallholder oil palm fields is limited by nutrients in scenarios with distinct sources of planting material.

METHODS: We collected detailed data on leaf nutrient concentration from 30 fields to derive minimum sampling size needed to diagnose nutrient status. Subsequently, we collected data on …