Horticulture Commons^™

Do Coffee Agroforestry Systems Always Improve Soil Carbon Stocks Deeper In The Soil?—A Case Study From Turrialba, Costa Rica, Nilovna Chatterjee, P. K. Ramachandran Nair, Vimala D. Nair, Abhishek Bhattacharjee, Elias De Melo Virginio Filho, Rheinhold G. Muschler, Martin R.A. Noponen

Department of Agronomy and Horticulture: Faculty Publications

Shaded perennial agroforestry systems (AFS) are regarded as desirable land‐use practices that improve soil carbon sequestration. However, most studies assume a positive correlation between above ground and below ground carbon without considering the effect of past and current land management, textural variations (silt and clay percentage), and such other site‐specific factors that have a major influence on the extent of soil C sequestration. We assessed SOC stock at various depths (0–10, 10–30, 30–60, and 60–100 cm) in shaded perennial coffee (Coffea arabica L.) AFS in a 17‐ year‐old experimental field at the Centro Agronómico Tropical de Investigación y Enseñanza, (9°53′44′′ …

Establishment Of Wildflower Islands To Enhance Roadside Health And Aesthetics, Walter Schacht, Judy Wu-Smart

Nebraska Department of Transportation: Research Reports

Wildflowers are crucial in the ecological function of the low-input roadside plant communities in terms of water andnutrient cycling, nutrient inputs such as nitrogen, total plant canopy cover, stand longevity, and provision of habitat for numerous small animals. Further, wildflowers provide critical foraging and nesting resources for birds, insects, and other wildlife. Unfortunately, habitat loss from agricultural and urban development has led to rapid population declines in wild bees and other pollinators across the US, thereby jeopardizing not only food production but also the sustainability of our natural landscapes (Kearns & Inouye, 1997). One way to mitigate wild bee decline …

Pi‑Plat: A High‑Resolution Image‑Based 3d Reconstruction Method To Estimate Growth Dynamics Of Rice Inflorescence Traits, Jaspreet Sandhu, Feiyu Zhu, Puneet Paul, Tian Gao, Balpreet K. Dhatt, Yufeng Ge, Paul E. Staswick, Hongfeng Yu, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Background: Recent advances in image-based plant phenotyping have improved our capability to study vegetative stage growth dynamics. However, more complex agronomic traits such as inflorescence architecture (IA), which predominantly contributes to grain crop yield are more challenging to quantify and hence are relatively less explored. Previous efforts to estimate inflorescence-related traits using image-based phenotyping have been limited to destructive end-point measurements. Development of non-destructive inflorescence phenotyping platforms could accelerate the discovery of the phenotypic variation with respect to inflorescence dynamics and mapping of the underlying genes regulating critical yield components.

Results: The major objective of this study is to evaluate …

Long-Lasting Insecticide Netting For Protecting Tree Stems From Attack By Ambrosia Beetles (Coleoptera: Curculionidae: Scolytinae), Christopher M. Ranger, Christopher T. Werle, Peter B. Schultz, Karla M. Addesso, Jason B. Oliver, Michael E. Reding

Agricultural and Environmental Sciences Faculty Research

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) are destructive wood-boring insects of horticultural trees. We evaluated long-lasting insecticide netting for protecting stems against ambrosia beetles. Container-grown eastern redbud, Cercis canadensis, trees were flood-stressed to induce ambrosia beetle attacks, and deltamethrin-treated netting was wrapped from the base of the stem vertically to the branch junction. Trees were deployed under field conditions in Ohio, Virginia, Tennessee, and Mississippi with the following treatments: (1) flooded tree; (2) flooded tree with untreated netting; (3) flooded tree with treated ‘standard mesh’ netting of 24 holes/cm²; (4) flooded tree with treated ‘fine mesh’ netting of 28 …

Divergent Phenotypic Response Of Rice Accessions To Transient Heat Stress During Early Seed Development, Puneet Paul, Balpreet K. Dhatt, Jaspreet Sandhu, Waseem Hussain, Larissa Irvin, Gota Morota, Paul E. Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Increasing global surface temperatures is posing a major food security challenge. Part of the solution to address this problem is to improve crop heat resilience, especially during grain development, along with agronomic decisions such as shift in planting time and increasing crop diversification. Rice is a major food crop consumed by more than 3 billion people. For rice, thermal sensitivity of reproductive development and grain filling is well-documented, while knowledge concerning the impact of heat stress (HS) on early seed development is limited. Here, we aim to study the phenotypic variation in a set of diverse rice accessions for elucidating …

Deep Kernel And Deep Learning For Genome-Based Prediction Of Single Traits In Multienvironment Breeding Trials, José Crossa, Johannes W.R. Martini, Daniel Gianola, Paulino Pérez-Rodríguez, Diego Jarquin, Philomin Juliana, Osval Antonio Montesinos López, Jaime Cuevas

Department of Agronomy and Horticulture: Faculty Publications

Deep learning (DL) is a promising method for genomic-enabled prediction. However, the implementation of DL is difficult because many hyperparameters (number of hidden layers, number of neurons, learning rate, number of epochs, batch size, etc.) need to be tuned. For this reason, deep kernel methods, which only require defining the number of layers, may be an attractive alternative. Deep kernel methods emulate DL models with a large number of neurons, but are defined by relatively easily computed covariance matrices. In this research, we compared the genome-based prediction of DL to a deep kernel (arc-cosine kernel, AK), to the commonly used …

Plant Hormones Differentially Control The Sub-Cellular Localization Of Plasma Membrane Microdomains During The Early Stage Of Soybean Nodulation, Zhenzhen Qiao, Prince Zogli, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Phytohormones regulate the mutualistic symbiotic interaction between legumes and rhizobia, nitrogen-fixing soil bacteria, notably by controlling the formation of the infection thread in the root hair (RH). At the cellular level, the formation of the infection thread is promoted by the translocation of plasma membrane microdomains at the tip of the RH. We hypothesize that phytohormones regulate the translocation of plasma membrane microdomains to regulate infection thread formation. Accordingly, we treated with hormone and hormone inhibitors transgenic soybean roots expressing fusions between the Green Fluorescent Protein (GFP) and GmFWL1 or GmFLOT2/4, two microdomain-associated proteins translocated at the tip of the …

Critical Time For Weed Removal In Corn (Zea Mays L.) As Influenced By Pre Herbicides, Ayse Nur Ulusoy

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

A weed control program that utilizes PRE herbicides and ensures a timely post-emergence weed removal could protect growth and yield of corn. The use of pre-emergence (PRE) herbicides for weed control could reduce the need for multiple POST applications of glyphosate in glyphosate-tolerant (GT) corn and provide an additional mode of action for combating glyphosate-resistant weeds. Thus, field studies were conducted in 2017 and 2018 at Concord, NE with the following objectives develop weed management recommendations that considers soil applied herbicides and determine proper timing of glyphosate based on the crop growth stage.

Therefore the material in this thesis is …

Performance Of 10 Slicing Cucumbers In Southwest Michigan, Ron G. Goldy

Midwest Vegetable Trial Reports

Fruit quality and yield were lower than in previous Southwest Michigan Research and Extension Center slicing cucumber trials. This may primarily be to lower bee activity affecting pollination, fruit set and fruit shape. However, from this trial Bristol, SVCS0927, LS 75-1011, Darlington, and Perfect 10 deserve consideration for further commercial planting in Southwest Michigan.

Evaluation Of Transplant Root Length On Bell Pepper Yield And Quality, Ron G. Goldy

Midwest Vegetable Trial Reports

Allowing bell pepper transplants to develop a taproot system was detrimental to early plant growth. However, it did not have a significant detrimental effect on most fruit yield and quality parameters measured, and by final harvest, plants of all three root length treatments had similar above ground plant weights.

Performance Of 18 Fresh Market And Eight Saladette Tomato Cultivars In Southwest Michigan In 2019, Ron G. Goldy

Midwest Vegetable Trial Reports

It was again a difficult year for growing tomatoes at the Southwest Michigan Research and Extension Center. Rain shortly after field planting induced early bacterial disease infection, leading to defoliation and decreased fruit quality. The best performers in the fresh market trial were Red Snapper, Camaro, Saybrook, Jolene, and Myrtle. It was difficult to get good separation in the saladette trial. No entries rose above the others.

Response Of Cucumber, Yellow Squash, And Zucchini To Six Nitrogen Rates, Ron G. Goldy

Midwest Vegetable Trial Reports

There were few significant differences across the six nitrogen levels for the traits measured for all three crops. No clear trends were observed as nitrogen level was increased from 50 to 175#/acre. Better separation may have been obtained with more replication. Results indicate growers of slicing cucumber, yellow squash, and zucchini should be able to obtain adequate fruit yields using a season total of between 75 and 100#/acre nitrogen.

Determining Water Requirements In Turfgrass Systems, Tyler Quinn Carr

Graduate Theses and Dissertations

Turfgrass lawns are commonly utilized for home and commercial applications because of the aesthetic, environmental, and recreational benefits grasses provide, but many people perceive turfgrass as solely an aesthetic benefit that requires significant water inputs. It is important to identify and use turfgrass cultivars that have known drought tolerance, and also fine-tune and throughout development. A series of field experiments were conducted to determine the water requirements of turfgrass lawn systems with the following objectives: 1) investigate differences in chronic drought resistance and irrigation recommendations among cultivars of Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) 2) …

Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez

Graduate Theses and Dissertations

In experiment 1, 80 steers (197.0 kg initial body weight; BW for fall, 116.9 kg for spring), were stocked at 2.45 and 4.1 calves/ha in fall and spring, respectively in 16 tall fescue pastures [fall ergovaline (EV) = 1,475 ppb and spring EV = 1,173 ppb] under 2 treatments, mineral (MIN) (n = 8) and cumulative management (CM) (n = 8). Forage allowance did not differ (P = 0.76) between CM and MIN during fall but differed during spring (P ≤ 0.05, 2.55 vs. 3.22 kg DM/kg BW, for MIN and CM, respectively). For fall, average daily gain (ADG) resulted …

Arkansas Soybean Research Studies 2018, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading soybean-producing state in the mid-southern United States. Arkansas ranked 11th in soybean production in 2018 when compared to the other soybean-producing states in the U.S. The state represents 3.7% of the total U.S. soybean production and 3.7% of the total acres planted in soybean in 2018. The 2018 state soybean average was 50.5 bushels per acre, half a bushel lower than the state record set in 2017. The top five soybean-producing counties in 2018 were Mississippi, Desha, Phillips, Arkansas, and Poinsett Counties (Table 1). These five counties accounted for 33.7% of soybean production in Arkansas in …

Comparison Of Morphological Traits In Cowpea Pod Length, Seed Number Per Pod, Seed Weight, Seed Color And Seed Density In Usda Germplasm Accessions And Arkansas Breeding Lines, Sora Imamura

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The objective of the study was to compare and correlate the Arkansas cowpea breeding lines to the USDA cowpea germplasm accessions on the following morphological traits: seed color, pod length, number of seeds per pod, 100 seed weight, and seed density. The seed density is defined as the weight of seed in gram per centimeter of pod length. Three hundred seventeen cowpea genotypes were used in this experiment. Out of the 317, 285 germplasm accessions were from the USDA GRIN and 32 lines were from the Arkansas breeding program.

T-test between Arkansas breeding lines and USDA germplasm accessions were done …

Arkansas Soybean Performance Tests 2019, J. F. Carlin, R. D. Bond, J. A. Still

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.

Evaluation Of Pheromone Mating Disruption For California Red Scale Control In Commercial California Citrus, Joel Timothy Leonard

Master's Theses

California red scale (CRS), Aonidella aurantii, is an increasingly injurious insect pest for the California citrus industry due to insecticide resistance, changing weather patterns, and shifting trade regulations. The presence of the insect on fruit, damages the rind of the fruit and high populations can cause dieback of branches as well as lower yields. Pheromone mating disruption of CRS has the potential to alleviate population control concerns and reduce insecticide use. The efficacy of the pheromone mating disruption technique for pest management of CRS was determined using the products CheckMate® CRS and Semios CRS Plus. CheckMate® CRS was evaluated …

Genetic Resistance To The Downy Mildew Pathogen And Mapping The Rpf Resistance Loci In Spinach, Gehendra Bhattarai

Graduate Theses and Dissertations

Spinach (Spinacia oleracea) is an important cool-season leafy vegetable crop in the United States (US). Downy mildew, caused by the obligate oomycete Peronospora effusa, is the most economically important disease of spinach. A total of 17 races of P. effusa have been reported on spinach, and many of these races (>10) have emerged in the last three decades. The new races of the pathogen are continually overcoming the genetic resistances used in the newly released cultivars.

A detached leaf inoculation assay was evaluated, standardized, and validated as a new method to differentiate resistant and susceptible spinach genotypes. Disease response …

Cover Crops As An Integrated Approach For Pest Suppression And Pollinator Promotion In Arkansas Watermelon Production Systems, Paige Laurel Hickman

Graduate Theses and Dissertations

Arkansas watermelon growers face a variety of insect pest and disease problems that have the potential to threaten yield. Integrated pest management tactics can provide control over these threats and are intended to cut down on pesticide use and its associated negative impacts like pesticide resistance, non-target effects, and runoff. Cover crops provide an array of benefits and can be useful in integrated pest management. Evidence has shown that certain cover crops can increase beneficial insects and suppress disease in the following cash crop. They can also provide important resources to pollinators. In order to build a better understanding of …

Evaluation Of Detached Strawberry Leaves For Anthracnose Disease Severity Using Image Analysis And Visual Ratings, Melinda A. Miller-Butler, Barbara J. Smith, Kenneth J. Curry, Eugene K. Blythe

Faculty Publications

Inoculation of detached strawberry leaves with Colletotrichum species may provide an accurate, rapid, nondestructive method of identifying anthracnose-resistant germplasm. The purpose of this study was to statistically compare two methods (visual and image analysis) of evaluating disease severity of strawberry germplasm screened for anthracnose resistance. Detached leaves of 77 susceptible and resistant strawberry clones were inoculated with one Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. and two C. fragariae A. N. Brooks isolates. Anthracnose disease symptoms on each leaf were assessed quantitatively via computer-based image analysis to determine percentage lesion area and qualitatively by two independent raters using a visual disease …

Effects Of Different Water And Nitrogen Regimens On Yield Of Winter Wheat Produced In Nebraska, Joseph Emory Davis

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

Wheat is the 3rd most prominent crop in the USA and approximately 50% is exported annually. Nebraska wheat production is 11^th in the country, and it plays a major role in the state's agricultural economy, especially in western NE. Generally, wheat is grown under dryland conditions and the region grows much more wheat on unirrigated land than it does on irrigated. However, deficit irrigation has shown great value in producing high yielding wheat with much less water than needed for other crops. Finding new ways to leverage irrigation in wheat production may help address the need to produce food …

Integration Of Cover Crops Into Midwest Corn-Soybean Cropping Systems And Potential For Weed Suppression, Joshua S. Wehrbein

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

Cover crops have potential to provide benefits to agricultural systems, such as improved soil productivity, nutrient scavenging, weed suppression, and livestock forage. There are several challenges associated with cover crop integration into traditional Midwest corn-soybean cropping systems. One of these challenges is timely establishment in the fall, which is limited by the relatively late harvest of corn and soybean. Cover crop effectiveness is related to the amount of biomass produced, thus maximizing the growth period in the fall is desired. To address this challenge, we evaluated the potential to utilize early-season soybean maturity groups (MGs) to allow for earlier soybean …

A Survey Of Soil Properties Affecting Vegetation Establishment Along Nebraska Highways, Shad D. Mills

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

Vegetation along roadsides is important to prevent soil erosion, provide habitat and filter water running off the road. Along some highways in Nebraska vegetation does not readily establish and persist. It is thought that sodium and bulk density issues are the driving factor behind the lack of vegetation. After a construction project, the shoulder is seeded into the compacted soil, and salts can accumulate in the soil due to deicing agents being used during the winter. The purpose of our study was to determine if the bulk density and sodium are the driving factors of the vegetation cover. We also …

Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio

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

A nitrogen (N) balance, calculated as the difference between N inputs and grain-N removal, provides an estimate of the potential N losses. We used N balance with other N-related metrics (partial factor productivity for N inputs, and yield-scaled N balance), to benchmark maize yields in relation with N input use in the US Corn Belt. We first used experimental data on grain-N concentration (GNC) to assess variation in this parameter due to biophysical and management factors. Subsequently, we used N balance and N-related metrics to benchmark yields in relation with N inputs in irrigated and rainfed fields in Nebraska using …

Spring Black Rot-Resistant Cabbage Cultivar Evaluation, Chris Smigell, John Strang, John Snyder

Midwest Vegetable Trial Reports

Fourteen green fresh-market cabbage cultivars were evaluated at the University of Kentucky horticultural farm in Lexington in a replicated trial to evaluate their performance in Central Kentucky. Cultivars were listed in seed catalogs as having black rot (Xanthomonas campestris) resistance or tolerance. Cultivars were grown on bare soil following University of Kentucky recommendations to commercial cabbage growers. Plants were not inoculated with X. campestris, and Badge SC bactericide was applied once early in the season. ‘Lucky Ball’ was the top-performing early-season cultivar, being consistently tender, sweet to slightly sweet, and having little to no sulfur aftertaste. Its …

Impact Of Cover Crop Usage On Soilborne Diseases In Field Nursery Production, Sujan Dawadi, Fulya Baysal-Gurel, Karla M. Addesso, Jason B. Oliver, Terri Simmons

Agricultural and Environmental Sciences Faculty Research

Soilborne pathogens are a significant economic problem for nursery production in the Southeastern United States. The goal of this study was to determine the impact of cover crops on soilborne disease suppressiveness in such systems. Soils from red maple (Acer rubrum L.) plantation fields grown with and without cover crops were sampled, either while the cover crops were growing (pre-disked) or post-season, following cover crop incorporation into the soil (post-disked). Greenhouse bioassays were conducted using red maple seeds on inoculated (with Rhizoctonia solani (J.G. Kühn) or Phytophthora nicotianae (Breda de Haan)) and non-inoculated field soils. The damping-off, root rot disease …

Evaluation Of A Global Spring Wheat Panel For Stripe Rust: Resistance Loci Validation And Novel Resources Identification, Ibrahim Elbasyoni, Walid M. El-Orabey, Sabah Morsy, P. S. Baenziger, Zakaria Al Ajlouni4, Ismail M. Dweikat

Department of Agronomy and Horticulture: Faculty Publications

Stripe rust (incited by Puccinia striiformis f. sp. tritici) is airborne wheat (Triticum aestivum L.) disease with dynamic virulence evolution. Thus, anticipatory and continued screening in hotspot regions is crucial to identify new pathotypes and integrate new resistance resources to prevent potential disease epidemics. A global wheat panel consisting of 882 landraces and 912 improved accessions was evaluated in two locations in Egypt during 2016 and 2017. Five prevalent and aggressive pathotypes of stripe rust were used to inoculate the accessions during the two growing seasons and two locations under field conditions. The objectives were to evaluate the panel for …

Influence Of Vermicompost Tea On Secondary Metabolites In Solanum Lycopersicum Within South Florida, Daphne K. Sugino Souffront

FIU Electronic Theses and Dissertations

Fresh Market Tomatoes provide a high revenue stream for Florida’s agricultural sector. To attain profitable yields, farmers introduce high inputs of pesticides to suppress pest invasion/damage. Heavy usage of pesticides has adverse effects on human and environmental health. A possible solution might be the incorporation of vermicompost in pest management. Typically used as a fertilizer, vermicompost has pest suppressant properties. Mechanisms influencing enhanced pest resistance are unknown. To identify such mechanisms, a study was conducted to evaluate physical and chemical changes of the BHN589 tomato plant following the addition of varying vermicompost tea treatments (T5%, T10%, and T20%) . Results …

Metabolic Dynamics Of Developing Rice Seeds Under High Night-Time Temperature Stress, Balpreet K. Dhatt, Nathan Abshire, Puneet Paul, Kalani Hasanthika, Jaspreet Sandhu, Qi Zhang, Toshihiro Obata, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

High temperature stress during rice reproductive development results in yield losses. Reduced grain yield and grain quality has been associated with high temperature stress, and specifically with high night-time temperatures (HNT). Characterizing the impact of HNT on the phenotypic and metabolic status of developing rice seeds can provide insights into the mechanisms involved in yield and quality decline. Here, we examined the impact of warmer nights on the morphology and metabolome during early seed development in six diverse rice accessions. Seed size was sensitive to HNT in four of the six genotypes, while seed fertility and seed weight were unaffected. …