Plant Breeding and Genetics Commons^™

The Pseudomonas Syringae Type Iii Effector Hopg1 Targets Mitochondria, Alters Plant Development, And Suppresses Plant Innate Immunity, Anna Block, Ming Guo, Guangyong Li, Christian Elowsky, Thomas Clemente, James R. Alfano

Center for Plant Science Innovation: Faculty and Staff Publications

The bacterial plant pathogen Pseudomonas syringae uses a type III protein secretion system to inject type III effectors into plant cells. Primary targets of these effectors appear to be effector-triggered immunity (ETI) and pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI). The type III effector HopG1 is a suppressor of ETI that is broadly conserved in bacterial plant pathogens. Here we show that HopG1 from P. syringae pv. tomato DC3000 also suppresses PTI. Interestingly, HopG1 localizes to plant mitochondria, suggesting that its suppression of innate immunity may be linked to a perturbation of mitochondrial function. While HopG1 possesses no obvious mitochondrial signal …

Combining Local- And Large-Scale Models To Predict The Distributions Of Invasive Plant Species, Chad C. Jones, Steven A. Acker, Charles B. Halpern

Botany Faculty Publications

Habitat-distribution models are increasingly used to predict the potential distributions of invasive species and to inform monitoring. However, these models assume that species are in equilibrium with the environment, which is clearly not true for most invasive species. Although this assumption is frequently acknowledged, solutions have not been adequately addressed. There are several potential methods for improving habitat-distribution models. Models that require only presence data may be more effective for invasive species, but this assumption has rarely been tested. In addition, combining modeling types to form ‘ensemble’ models may improve the accuracy of predictions. However, even with these improvements, models …

Alkylresorcinol Synthases Expressed In Sorghum Bicolor Root Hairs Play An Essential Role In The Biosynthesis Of The Allelopathic Benzoquinone Sorgoleone, Daniel Cook, Agnes M. Rimando, Thomas E. Clemente, Joachim Schroder, Franck E. Dayan, N. P. Dhammika Nanayakkara, Zhiqiang Pan, Brice P. Noonan, Mark Fishbein, Ikuro Abe, Stephen O. Duke, Scott R. Baerson

Center for Plant Science Innovation: Faculty and Staff Publications

Sorghum bicolor is considered to be an allelopathic crop species, producing phytotoxins such as the lipid benzoquinone sorgoleone, which likely accounts for many of the allelopathic properties of Sorghum spp. Current evidence suggests that sorgoleone biosynthesis occurs exclusively in root hair cells and involves the production of an alkylresorcinolic intermediate (5-[(Z,Z)-8',11',14'-pentadecatrienyl]resorcinol) derived from an unusual 16:3D^9,12,15 fatty acyl-CoA starter unit. This led to the suggestion of the involvement of one or more alkylresorcinol synthases (ARSs), type III polyketide synthases (PKSs) that produce 5-alkylresorcinols using medium to long-chain fatty acyl-CoA starter units via iterative condensations with malonyl-CoA. In an effort …

Crop Updates 2010 - Crop Specific, Hugh J. Beckie, Wallace Cowling, T. N. Khan, K. Adhikari, K. Siddique, J. Garlinge, L. Smith, S. Morgan, C. Boyd, Ian Pritchard, Chris Veitch, Alan Harris, Tony Leonforts, Murray Blyth, Shari Dougal, Kristy Hobson, Ben Curtis, Doug Sawkins, D. Stephens, Ciara Beard, Kith Jayasena, Kazue Tanaka, Anne Smith, Brenda Coutts, Roger Jones, Jean Galloway, Pip Payne, Tess Humphreys, William Macleod, Ravjit Khangura, M. Aberra, H. Mian, Geoff Thomas, Dusty Severtson, Peter Mangano, Monica Kehoe, Madeline A. Tucker, Neil Barker, Robert Loughman, Larisa Cato, Ken Quail, Mohammad Amjad, Mark Seymour, Justin Kudnig, Mark Thompson, Anton Mannes, Michael Uttley, Chris Fletcher, Andrew Etherton, Nick Joyce, Kate Light, Peter Hamblin, Michael Lamond, Alan Meldrum, Wayne Parker, Steve Penny Jr, Sarah Ellis, Brenda Shackley, Christine Zaicou, Shajahan Miyan, Darshan Sharma, Ben Curtis, Greg Shea, Bevan Buirchell, David Harris, Bob French

Crop Updates

This session covers twenty four papers from different authors:

PLENARY

1. Challenges facing western Canadian cropping over the next 10 years, Hugh J Beckie, Research Centre, Agriculture and Agri-Food Canada, Saskatoon,

Saskatchewan

CROP SPECIFIC

Breeding

2. The challenge of breeding canola hybrids – new opportunities for WA growers, Wallace Cowling, Research Director, Canola Breeders Western Australia Pty Ltd

3. Chickpea 2009 crop variety testing of germplasm developed by DAFWA/CLIMA/ICRISAT/COGGO alliance. Khan, TN1,3, Adhikari, K1,3, Siddique, K2, Garlinge, J1, Smith, L1, Morgan, S1 and Boyd, C1 1Department …

Genetically Modified Canola Trials In 2009, Department Of Agriculture And Food, Western Australia

Research Reports

During 2009, just over 860 hectares of Roundup Ready® canola were grown in Western Australia enabled by an exemption order under the Genetically Modified Crops Free Areas Act 2003. The aim of the trials was to establish whether GM canola could be segregated from non-GM canola along the WA supply chain, and whether GM canola was agronomically viable for WA farming systems. This was the first time genetically modified canola had been grown on a commercial scale in WA - earlier exemptions for smaller trials had been for variety testing and scientific purposes.

Implications Of The Plastid Genome Sequence Of Typha (Typhaceae, Poales) For Understanding Genome Evolution In Poaceae, Mary M. Guisinger, Timothy W. Chumley, Jennifer V. Kuehl, Jeffrey L. Boore, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Plastid genomes of the grasses (Poaceae) are unusual in their organization and rates of sequence evolution. There has been a recent surge in the availability of grass plastid genome sequences, but a comprehensive comparative analysis of genome evolution has not been performed that includes any related families in the Poales. We report on the plastid genome of Typha latifolia, the first non-grass Poales sequenced to date, and we present comparisons of genome organization and sequence evolution within Poales. Our results confirm that grass plastid genomes exhibit acceleration in both genomic rearrangements and nucleotide substitutions. Poaceae have multiple structural rearrangements, including …

Translational Inhibition By Micrornas In Plants, Bin Yu, Hai Wang

Center for Plant Science Innovation: Faculty and Staff Publications

MicroRNAs (miRNAs) are 21–24 nucleotide riboregulators, which selectively repress gene expression through transcript cleavage and/or translational inhibition. It was thought that most plant miRNAs act through target transcript cleavage due to the high degree of complementarity between miRNAs and their targets. However, recent studies have suggested widespread translational inhibition by miRNAs in plants. The mechanisms underlining translational inhibition by plant miRNAs are largely unknown, but existing evidence has indicated that plants and animals share some mechanistic similarity of translational inhibition. Translational inhibition by miRNAs has been shown to regulate floral patterning, floral timing, and stress responses. This chapter covers recent …

Turnover Of Mature Mirnas And Sirnas In Plants And Algae, Heriberto Cerutti, Fadia Ibrahim

Center for Plant Science Innovation: Faculty and Staff Publications

rnicroRNAs (miRNAs) and small interfering RNAs (siRNAs) play important roles in gene regulation and defense responses against transposons and viruses in eukaryotes. These small RNAs generally trigger the silencing of cognate sequences through a variety of mechanisms, including RNA degradation, translational inhibition, and transcriptional repression. In the past few years, the synthesis and the mode of action of miRNAs and siRNAs have attracted great attention. However, relatively little is known about mechanisms of quality control during small RNA biogenesis as well as those that regulate mature small RNA stability. Recent studies in Arabidopsis thaliana and Caenorhahditis elegans have implicated 3′-to-5′ …

Spring Seed Guide 2010: Nebraska Variety And Hybrid Tests -- Soybeans, Teshome Regassa, Robert N. Klein, Bruce Anderson, Charles A. Shapiro, Jim Krall

Department of Agronomy and Horticulture: Faculty Publications

NEBRASKA SOYBEAN VARIETY TESTS 2009

Crop Production Summary: The November 2009 estimated soybean yield for Nebraska was 52 bushels per acre from 4.800 million harvested acres. The total production of soybeans for the state was forecasted at 247 million bushels. These estimates are from the November National Agricultural Statistics Service.

Insights Into The World Of Pea Nodulation Using The Low Nodulator R50, Scott Clemow

Theses and Dissertations (Comprehensive)

Cytokinin oxidase (CKX) is the enzyme responsible for the degradation of cytokinin, a class of adenine-based plant hormones that stimulate cell division, among other physiological processes. The pea mutant R50 is characterized by having a pale leaf phenotype, dwarf stature, few lateral roots, low nodule formation, and elevated levels of endogenous cytokinins in its shoots, roots and nodules. When compared to that of the wild-type Sparkle, total CKX activity is low but the transcript levels of PsCKX1 are significantly higher. In this study, I investigated the expression of PsCKX1 throughout the development of a nodule and the localization of PsCKX1 …

Genetic Diversity, Micro Propagation, And Cold Hardiness Of Ilex Glabra (L.) A. Gray, Youping Sun

Electronic Theses and Dissertations

Ilex glabra (L.) A.Gray (inkberry) is a native evergreen shrub with dark green foliage and compact habit. This shrub has gained popularity in the northern landscapes of the United States and more nursery growers would like to produce it. To better understand genetic relationships among inkberry cultivars and breed cold-hardy cultivars for northern nursery growers and landscape specialists, the following projects were conducted. A group of 48 inkberry accessions and two other Ilex species (Ilex crenata Thunb. and I. mutchagara Makino) were studied using amplified fragment length polymorphism (AFLP) markers. A total of 229 markers between 50 and 500 base …

Genetic Diversity Of Wheat Cultivars From Turkey And U.S. Great Plains, Anyamanee Auvuchanon

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

Genetic diversity of wheat cultivars from Turkey and the Great Plains was studied under the hypothesis ‘Turkey’ wheat originated from Turkey and is the original hard red winter wheat landrace in the Great Plains. Wheat cultivars in Turkey and the Great Plains were selected for adaptation in two countries which were similar in climate. Twenty-two Turkish and twenty-three Great Plains wheat cultivars were selected for this study using SSR markers, agronomic, and end-use quality traits data. Wheat cultivars were clustered into five groups based on SSR markers and the clustering largely followed their countries of origin and pedigree. Modern Great …

Characterization And Inheritance Assessment Of Fruit And Leaf Shape In Unique Vitis Seedlings, Paul J. Sandefur, John R. Clark, Douglas Karcher

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

From August to October of 2009, two separate studies were conducted to assess fruit shape of Vitis section Euvitis hybrid bunch grapes using digital photography (Study 1) and evaluate inheritance of leaf shape in unique populations of V. rotundifolia hybrids (Vitis section Muscadinia) (Study 2). All vines studied were located at the University of Arkansas Fruit Research Station, Clarksville. Study 1 used SigmaScan® digital photography analysis software to calculate shape factor, major:minor axis ratio, and compactness of highly variable, unique-shaped fruit from a population of 182 Euvitis seedlings. SigmaScan® accurately characterized fruit shape elongation as had been recorded in previous …

The Pleiotropic Mutant R50 (Sym16): A Link Between Cytokinin And Starch Metabolism May Explain Its Seed Phenotype, Chengli Long

Theses and Dissertations (Comprehensive)

Cytokinins are a class of adenine-based plant hormones that stimulate cell divisions and are therefore essential for organ growth and development. The role that cytokinin plays in nodulation and that of R50 (syml6) in particular is very complex. In this study, a cytokinin antagonist and a cytokinin oxidase (CKX) inhibitor were used as tools to study the effects of cytokinin perception or cytokinin degradation on nodulation in pea, the cytokinin transduction pathway, especially that induced by CRE1/AHK4, and CKX play a significant role in pea nodulation. Comparison of the full length sequences PsCKX2 cDNAs from Sparkle and R50 …

Assessing Genetic Differentiation Among Populations Of The Invasive Plant Impatiens Glandulifera In Maine, Jordan R. Schoonover

Honors Theses

The annual herbaceous plant Impatiens glandulifera Royle is native to the Himalayas and is a significant invasive species in Europe. In the past century, it was introduced to the United States, where it has become established in 12 states. This study evaluated genetic differentiation among four Maine populations, to address a theory that posits hybridization of distinct lineages as a trigger for invasiveness. Regions of microsatellite repeats were evaluated at two polymorphic loci for 41 plants sampled from the four populations. A striking finding was that the observed heterozygosity was substantially higher than the heterozygosity expected from random combination of …

Production Of Premium Waxflowers, Kevin Seaton, Nikki Poulish

Bulletins 4000 -

The cut flower trade is a highly competitive global market. Waxflowers are grown around the world—often in countries with lower cost structures or closer proximity to our main markets. Western Australian producers can only compete if their product stands out from the crowd in terms of quality, presentation and uniqueness, however, it still has to represent good value for money.

Nomenclatural Changes For Some Grasses In California And The Muhlenbergia Clade (Poaceae), James Payne Smith Jr.

James Payne Smith

No abstract provided.