Life Sciences Commons^™

Pearl Millet Response To Drought: A Review, Nikee Shrestha, Hao Hu, Kumar Shrestha, Andrew N. Doust

Department of Agronomy and Horticulture: Faculty Publications

The C4 grass pearl millet is one of the most drought tolerant cereals and is primarily grown in marginal areas where annual rainfall is low and intermittent. It was domesticated in sub-Saharan Africa, and several studies have found that it uses a combination of morphological and physiological traits to successfully resist drought. This review explores the short term and long-term responses of pearl millet that enables it to either tolerate, avoid, escape, or recover from drought stress. The response to short term drought reveals fine tuning of osmotic adjustment, stomatal conductance, and ROS scavenging ability, along with ABA and ethylene …

Pearl Millet Response To Drought: A Review, Nikee Shrestha, Hao Hu, Kumar Shrestha, Andrew N. Doust

Department of Agronomy and Horticulture: Faculty Publications

The C4 grass pearl millet is one of the most drought tolerant cereals and is primarily grown in marginal areas where annual rainfall is low and intermittent. It was domesticated in sub-Saharan Africa, and several studies have found that it uses a combination of morphological and physiological traits to successfully resist drought. This review explores the short term and long-term responses of pearl millet that enables it to either tolerate, avoid, escape, or recover from drought stress. The response to short term drought reveals fine tuning of osmotic adjustment, stomatal conductance, and ROS scavenging ability, along with ABA and ethylene …

Effect Of Water Stress On Weed Germination, Growth Characteristics, And Seed Production: A Global Meta-Analysis, Mandeep Singh, Resham Thapa, Meetpal Singh Kukal, Suat Irmak, Steven Mirsky, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds compete with crops for soil moisture, along with other resources, which can impact the germination, growth, and seed production of weeds; however, this impact has not been systematically recorded and synthesized across diverse studies. To address this knowledge gap, a global meta-analysis was conducted using 1,196 paired observations from 86 published articles assessing the effect of water stress on weed germination, growth characteristics, and seed production. These studies were conducted and published during 1970 through 2020 across four continents (Asia, Australia, Europe, and North America). Imposed water stress was expressed as solution osmotic potential (ψsolution), soil water potential (ψsoil), …

Inactivation Of The Entire Arabidopsis Group Ii Gh3s Confers Tolerance To Salinity And Water Deficit, Rubén Casanova-Sáez, Eduardo Mateo-Bonmatí, Jan Šimura, Aleš Pěnčík, Ondřej Novák, Paul Staswick, Karin Ljung

Department of Agronomy and Horticulture: Faculty Publications

Indole-3-acetic acid (IAA) controls a plethora of developmental processes. Thus, regulation of its concentration is of great relevance for plant performance. Cellular IAA concentration depends on its transport, biosynthesis and the various pathways for IAA inactivation, including oxidation and conjugation.

Group II members of the GRETCHEN HAGEN 3 (GH3) gene family code for acyl acid amido synthetases catalysing the conjugation of IAA to amino acids. However, the high degree of functional redundancy among them has hampered thorough analysis of their roles in plant development.

In this work, we generated an Arabidopsis gh3.1,2,3,4,5,6,9,17 (gh3oct) mutant to knock out the group II …

Characterization Of Salt And Drought Tolerance In Sunflower (Helianthus Annuus L.), Sevgi Saylak

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

Consequent to the increasing world population, food sources are needed to be increased to meet the nutritional needs. However, due to natural processes and agricultural activities, the most destructive environmental factors that limit crop production, soil salinity, and drought-exposed areas are growing. As one of the major oilseed crops, sunflower (Helianthus annuus L.), is considered to be moderately tolerant to salt and drought. Although it can grow in arid to semi-arid regions, increasing salinity and drought might adversely affect sunflower production. This study aimed to investigate several sunflower germplasms' morphological responses to salt and drought stresses. For this purpose, …

Leaf Angle Extractor: A High-Throughput Image Processing Framework For Leaf Angle Measurements In Maize And Sorghum, Sunil Kumar Kenchanmane Raju, Miles Adkins, Alex Enersen, Daniel Santana De Carvalho, Anthony J. Studer, Baskar Ganapathysubramanian, Patrick S. Schnable, James C. Schnable

Center for Plant Science Innovation: Faculty and Staff Publications

PREMISE: Maize yields have significantly increased over the past half-century owing to advances in breeding and agronomic practices. Plants have been grown in increasingly higher densities due to changes in plant architecture resulting in plants with more upright leaves, which allows more efficient light interception for photosynthesis. Natural variation for leaf angle has been identified in maize and sorghum using multiple mapping populations. However, conventional phenotyping techniques for leaf angle are low throughput and labor intensive, and therefore hinder a mechanistic understanding of how the leaf angle of individual leaves changes over time in response to the environment.

METHODS …

Leveraging Genome-Enabled Growth Models To Study Shoot Growth Responses To Water Deficit In Rice, Malachy T. Campbell, Alexandre Grondin, Harkamal Walia, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

lucidating genotype-by-environment interactions and partitioning its contribution to phenotypic variation remains a challenge for plant scientists. We propose a framework that utilizes genome-wide markers to model genotype-specific shoot growth trajectories as a function of time and soil water availability. A rice diversity panel was phenotyped daily for 21 d using an automated, high-throughput image-based, phenotyping platform that enabled estimation of daily shoot biomass and soil water content. Using these data, we modeled shoot growth as a function of time and soil water content, and were able to determine the time point where an inflection in the growth trajectory occurred. We …

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas Clemente, Paul Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced …

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas E. Clemente, Paul E. Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced …

Impact Of Drought On Chemical Composition And Sugar Yields From Dilute-Acid Pretreatment And Enzymatic Hydrolysis Of Miscanthus, A Tall Fescue Mixture, And Switchgrass, Amber Hoover, Rachel Emerson, Allison Ray, Daniel Stevens, Sabrina Morgan, Marnie Cortez, Robert Kallenbach, Matthew Sousek, Rodney Farris, Dayna Daubaras

Department of Agronomy and Horticulture: Faculty Publications

Environmental factors like drought impact the quality of biomass entering a bioconversion process. Drought often reduces the sugar content in lignocellulosic biomass, which could have economic impacts, particularly when compounded with losses in dry biomass yield; however, the effects on conversion efficiency are not completely understood. This study investigated how drought may impact biomass composition and sugar yields from dilute-acid pretreatment and enzymatic hydrolysis of Miscanthus, a tall fescue mixture, and switchgrass from Nebraska, Missouri, and Oklahoma, respectively, grown as part of Regional Feedstock Partnership field trials. Samples were grown and harvested in 2010 during non-drought conditions and in …

The Role Of Tre6p And Snrk1 In Maize Early Kernel Development And Events Leading To Stress-Induced Kernel Abortion, Samuel W. Bledsoe, Clémence Henry, Cara A. Griffiths, Matthew J. Paul, Regina Feil, John E. Lunn, Mark Stitt, L. Mark Lagrimini

Department of Agronomy and Horticulture: Faculty Publications

Background: Drought stress during flowering is a major contributor to yield loss in maize. Genetic and biotechnological improvement in yield sustainability requires an understanding of the mechanisms underpinning yield loss. Sucrose starvation has been proposed as the cause for kernel abortion; however, potential targets for genetic improvement have not been identified. Field and greenhouse drought studies with maize are expensive and it can be difficult to reproduce results; therefore, an in vitro kernel culture method is presented as a proxy for drought stress occurring at the time of flowering in maize (3 days after pollination). This method is used to …

Managing Drought Stress In California Agricultural Systems, Gregory D. Brittain Jr.

Doctor of Plant Health Program: Dissertations and Student Research

California is currently facing a historic drought, and this has led many farmers in the state to severely cut back on irrigation. Optimal use of water for irrigation requires a comprehensive understanding of how plants respond physiologically to water stress (Chapter 1). By monitoring water requirements in crops and managing irrigation to meet those requirements, growers can significantly reduce water use (Chapter 2). This can be done through improving application efficiency of irrigation technology as well as increasing the water use efficiency of the crops themselves. Deficit irrigation practices can be used to manipulate the physiology of water use in …

Impact Of Pre-Anthesis Water Deficit On Yield And Yield Components In Barley (Hordeum Vulgare L.) Plants Grown Under Controlled Conditions, Zakaria I. Al-Ajlouni, Ayed Al-Abdallat, Abdul Latief A. Al-Ghzawi, Jamal Y. Ayad, Jamal M. Abu Elenein, Nisreen A. Al-Quraan, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Drought at pre-anthesis stages can influence barley growth and results in yield losses. Therefore, it is important to understand how drought at pre-anthesis can affect different traits associated with yield reduction in barley. The objective of this study was to understand the relevance of the genetic background of major flowering time genes in barley plants subjected to pre-anthesis drought and its impact on yield and yield components. A glasshouse experiment using a Randomized Complete Block Design was conducted to investigate the effect of drought and its timing on yield and yield components on eleven barley genotypes, which were selected to …

Temporal Dynamics Of Maize Plant Growth, Water Use, And Leaf Water Content Using Automated High Throughput Rgb And Hyperspectral Imaging, Yufeng Ge, Geng Bai, Vincent Stoerger, James C. Schnable

Biological Systems Engineering: Papers and Publications

Automated collection of large scale plant phenotype datasets using high throughput imaging systems has the potential to alleviate current bottlenecks in data-driven plant breeding and crop improvement. In this study, we demonstrate the characterization of temporal dynamics of plant growth and water use, and leaf water content of two maize genotypes under two different water treatments. RGB (Red Green Blue) images are processed to estimate projected plant area, which are correlated with destructively measured plant shoot fresh weight (FW), dry weight (DW) and leaf area. Estimated plant FW and DW, along with pot weights, are used to derive daily plant …

When An Invasive Plant Fails To Invade, Stephen L. Young

West Central Research and Extension Center, North Platte

In 2012, much of the US Midwest was gripped in one of the most severe droughts on record. While conducting experimental fieldwork at a site in Nebraska during June of that year, I noticed a single musk thistle (Carduus nutans; Figure 1) that appeared to be in the bolt or early flowering stage, which is typical for the species at that time. Here, however, two things were unusual: this plant was less than 1 meter tall (with adequate moisture and light, musk thistle typically grows to heights of 1–2.5 meters before flowering), and was only 3 months old (the bolt …

Understanding Rice Adaptation To Varying Agro-Ecosystems: Trait Interactions And Quantitative Trait Loci, Shalabh Dixit, Alexandre Grondin, Cheng-Ruei Lee, Amelia Henry, Thomas-Mitchell Olds, Arvind Kumar

Department of Agronomy and Horticulture: Faculty Publications

Background: Interaction and genetic control for traits influencing the adaptation of the rice crop to varying environments was studied in a mapping population derived from parents (Moroberekan and Swarna) contrasting for drought tolerance, yield potential, lodging resistance, and adaptation to dry direct seeding. A BC₂F₃-derived mapping population for traits related to these four trait groups was phenotyped to understand the interactions among traits and to map and align QTLs using composite interval mapping (CIM). The study also aimed to identify QTLs for the four trait groups as composite traits using multivariate least square interval mapping (MLSIM) …

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Department of Agronomy and Horticulture: Faculty Publications

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus × giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced …