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B. R. Wells Rice Research Studies 2003, R. J. Norman, J.-F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice-producing state in the U.S., representing just over 48% of the total U.S. production and 48.5% of the total acres planted to rice. Rice cultural practices vary across the state and across the U.S. However, due to changing political, environmental, and economic times, the practices are dynamic. This survey was initiated in 2002 to monitor how the changing times reflect the 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 where rice is produced. Questions included topics such as …

Agribusiness Sheep Updates - 2004 Part 3, Ken Hart, Keith Croker, Rob Davidson, Mario D'Antuono, Evan Burt, Tanya Kilminster, Diana Fedorenko, Darryl Mcclements, Robert Beard, Sandy Turton, Martin Atwell, Robert Beard

Sheep Updates

Posters Can Merino Ewes be Teased to Synchronise Oestrus for a Summer/Autumn Mating? Ken Hart, Keith Croker, Department of Agriculture Western Australia, Rob Davidson, School of Animal Biology, University of Western Australia. Mario D'Antuono, Department of Agriculture Western Australia Damara Sheep: Now Looking Domestic Evan Burt and Tanya Kilminster, Department of Agriculture Western Australia Production and Water Use of Lucerne and French Serradella Under Three Sowing Rates Diana Fedorenko1,4, Darryl McClements1,4 , Robert Beard3,4 1Department of Agriculture, 3 Farmer, Meckering, 4CRC for Plant-based Management of Dryland Salinity. E-SHEEP - Individual Animal Management is here Sandy Turton & Martin Atwell, Department …

Moisture Potential Affects Rate Of Leaf Appearance In Cool Season Grasses, Nina Cherone Terrell

McCabe Thesis Collection

The rate of leaf appearance and onset of growth in cool season grasses may be influenced by soil moisture potential and exposure to below freezing temperatures. Levels of moisture potential and days exposed to freezing temperatures, which will restrict leaf appearance, are not well defined. The first part of this study was to determine the effects of different moisture potentials on the leaf appearance rates in two cool season grasses. Italian ryegrass (IRG) and tall wheat grass (TWG) were grown hydroponically at 4 moisture potentials in seed pouches in an incubator under a photoperiod of 13 hours light and 11 …

Influence Of Poultry Litter On Dark Tobacco Growth And Soil Nutrient Availability, Jason Simmons

Masters Theses & Specialist Projects

Due to the relatively high value of dark tobacco compared with fertilizer costs, nitrogen is recommended at levels as high as 338 kg ha"1. Such rates of inorganic fertilizers increase the osmotic pressure of the soil solution and soil acidity, often causing reduced stands, Mn toxicity, Mo and Ca deficiencies, and reduced yield and quality of the cured leaf (Sims et al., 1984). Poultry litter utilized as a nutrient source is an inexpensive alternative to this dilemma due to its relatively neutral or alkaline composition. However, due the amount of chloride present in poultry litter, the University of Kentucky advises …

Cattle As Grazing Management And Seed Dispersal Tools For Increasing Native Species Diversity On Great Basin Rangelands, Marina K. Whitacre

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments evaluated: 1) the influence of seed intake and gut retention time on seed passage, recovery, and germinability; 2) fecal seeding and broadcast /trampling as techniques to incorporate seeds into a well-established Agropyron desertorum (Fisch.) Schult. stand in Skull Valley , Utah; 3) intensive grazing as a means to reduce Agropyron biomass and increase establishment and survival of seeded species; and 4) the recovery and germinability of seed extracted from dung collected from the field. Two shrubs (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young and Atriplex confertifolia Torr. & Frem.), a grass (Elymus elymoides (Raf.) …

Crop Updates 2004 - Cereals, Wal Anderson, Vivian Vanstone, Rob Loughman, Vanessa Stewart, Darshan Sharma, Christine M. Zaicou-Kunesch, Brenda Shackley, Mohammad Amjad, Steve Penny Jr, Glen Riethmuller, Jeremy Lemon, Mario D'Antuono, Veronika Reck, Ben Curtis, Judith Devenish, Melaine Kupsch, Anne Smith, Blakely Paynter, Roslyn J. Jettner, Leanne Schulz, Jocelyn Ball, Tom Sweeny, Stephen Loss, Ashleigh Brooks, Justin Fuery, Geoff Anderson, Zed Rengel, Paul Damon, Eddy Pol, Narelle Hill, Ray Tugwell, Ron Mctaggart, Nathan Moyes, John Majewski, Manisha Shankar, James Piotrowski, Ciara Beard, Kithsiri Jayasena, Kazue Tanaka, Grey Poulish, Debbie Thackray, Rohan Prince, Roger Jones, Peter Nelson, Nigel Metz, Leisa Armstrong, Yee Leong (Alex) Yung, Moin U. Salam, David Tennant

Crop Updates

This session covers twenty eight papers from different authors:

PLENARY

1. Declining profitability in continuous cropping systems. Is more wheat the answer on Duplex soil? Dr Wal Anderson, Department of Agriculture

2. Disease implications of extending the wheat phase in low-medium rainfall areas, Dr Vivian Vanstone and Dr Robert Loughman, Department of Agriculture

3. Prolonged wheat phase on duplex soils – where do weeds set the boundary? Vanessa Stewart, Department of Agriculture

WHEAT AGRONOMY

4. Management of small grain screenings in wheat, Dr Wal Anderson and Dr Darshan Sharma, Department of Agriculture

5. Agronomic responses of new wheat varieties, Christine …

Establishing Effects Of Application Of Swine Manure On Crop Leaf Damage To Growing Crops, Charles Shapiro, University Of Nebraska-Lincoln

Department of Agronomy and Horticulture: Faculty Publications

Swine manure from a below barn storage facility was applied to growing corn and soybeans to determine phytotoxic effects. The manure had an electrical conductivity of around 20 mmhos/cm and was diluted for treatment at full, half, quarter and none. The manure mixtures were applied at a rate of 0.5 in/acre using a procedure that wet the foliage three times in a 15-minute time span. Manure mixtures were applied at V7 and V14 for corn and V3 and R1 for soybeans. Phytotoxic effects were shown at the high rate for both crops, but soybeans were killed at the early application …

Topcrop W.A. State Focus 2002-2003 Wheat Protein, Alison Slade, Jeremy Lemon

Bulletins 4000 -

The State Focus program is supported by the Grains Research and Development Corporation (GRDC) in conjunction with TOPCROP to provide grower groups with a new learning concept. The concept was developed in Victoria and has been adopted by South Australia and Western Australia.

Wheat protein was selected as the Western Australian State Focus in response to a wide-ranging consultation of grower groups, researchers and the TOPCROP West management group. As crop yield potential increases through matching varieties to growing season length, weed and disease control, and timely sowing systems, the crop’s demand for nitrogen increases. Unless the demand is matched …

Intsormil 2004 Annual Report, John M. Yohe, Thomas Crawford Jr., Kimberly Christiansen, Joan Frederick

INTSORMIL Impacts and Bulletins

The 2004 INTSORMIL Annual Report presents the progress and notable achievements by the SorghumlMillet CRSP during the period of July 1, 2003 - June 30, 2004. These results are an outcome of partnerships between scientists at six U.S. Land Grant Universities (Kansas State University, Mississippi State University, University of Nebraska, Purdue University, Texas A&M University and West Texas A&M University) and scientists of the Agricultural Research Service of the U.S. Department of Agriculture at Tifton, Georgia and National Agricultural Research Systems (NARS) and National Universities in nineteen countries in Central America, West Africa, East Africa and Southern Africa.

Agricultural research …

Grass Or Trees? Performance Of Riparian Buffers Under Natural Rainfall Conditions, Australia, Lucy Mckergow, I Prosser, R Grayson, David Weaver, D Heiner

Journal articles

Riparian vegetation can trap sediment and nutrients derived from hillslopes. Most research into the effectiveness of riparian buffers has been experimental and little quantitative data exists on performance under natural field conditions. This study reports on grass and tree buffer performance under natural rainfall conditions in two contrasting Australian environments. Buffers receiving runoff from hillslopes cropped with bananas were monitored over a 4-year period in the wet topics of Far North Queensland (FNQ). Runoff, bedload and suspended loads were measured leaving the crop and leaving 15 m wide dense grass and remnant rainforest riparian buffers. The grass buffer was able …

Manure Matters, Volume 10, Number 1, John Sweeten, Ron Miner, Carrie Tengman

Manure Matters (newsletter)

A Brief History and Background of the EPA CAFO Rule

U.S. Environmental Protection Agency (EPA) rules affecting animal feeding operations (AFOs) have evolved from the 1972 Federal Clean Water Act (CWA). Section 502 of the CWA specifically defined “feedlots” as “point sources” along with dozens of other industries such as meat processing and fertilizer manufacturing. The goal of the 1972 CWA was to restore “fishable, swimmable” quality of lakes, streams, and estuaries in the United States.
A federal permit program termed the National Pollutant Discharge Elimination System (NPDES) was created for point sources that discharged into “waters of the United …

Seed Quality Qtl In A Prominent Soybean Population, D. L. Hyten Jr., V. R. Pantalone, C. E. Sams, A. M. Saxon, D. Landau-Ellis, T. R. Stefaniak, M. E. Schmidt

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is a versatile crop due to its multitude of uses as a high protein meal and vegetable oil. Soybean seed traits such as seed protein and oil concentration and seed size are important quantitative traits. The objective of this study was to identify representative protein, oil, and seed size quantitative trait loci (QTL) in soybean. A recombinant inbred line (RIL) population consisting of 131 F6-derived lines was created from two prominent ancestors of North American soy-beans (‘Essex’ and ‘Williams’) and the RILs were grown in six environments. One hundred simple sequence repeat (SSR) markers …

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 5 2004, Several Authors

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

No abstract provided.

Instructions For Authors, Discovery Editors

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

No abstract provided.

Using Multi-Spectral Imagery To Evaluate Corn Grown Under Nitrogen And Drought Stressed Conditions, Shannon L. Osborne, James S. Schepers, Mike R. Schlemmer

Department of Agronomy and Horticulture: Faculty Publications

The in-season estimation of crop stresses which have the potential of adversely affecting crop yield and/or quality could allow producers to make in-season management decisions to correct for the particular stress. A field study was conducted to evaluate the use of multispectral imagery for estimating corn (Zea mays L.) grain yield, in-season biomass and nitrogen (N) concentration under varying N and drought stresses. The experiment was a split-plot design with three replications using a factorial arrangement of treatments. Three irrigation (whole-plot) treatments included dry land, irrigation based on 0.5, and full evapotranspiration (ET). Sub-plot treatments included five N …

Expression Of A Putative Flavonoid 3'-Hydroxylase In Sorghum Mesocotyls Synthesizing 3-Deoxyanthocyanidin Phytoalexins, Jayanand Boddu, Catherine Svabek, Rajandeep Sekhon, Amanda Gevens, Ralph L. Nicholson, A. Daniel Jones, Jeffrey F. Pedersen, David L. Gustine, Surinder Chopra

Department of Agronomy and Horticulture: Faculty Publications

In sorghum, ingress of Cochliobolus heterostrophus stimulates the synthesis of 3-deoxyanthocyanidins that act as phytoalexins. Apigeninidin and luteolinidin are two major phytoalexins induced in the first 24 h after infection. In an attempt to understand genetic regulation of the biosynthesis of sorghum phytoalexins, we isolated a differentially expressed partial cDNA. Characterization and comparison showed that this cDNA sequence corresponds to a putative flavonoid 3’-hydroxylase. Full length sequence characterization allowed us to establish that the sorghum putative f3’h cDNA encodes a peptide of 517 amino acids that has domains conserved among cytochrome P450 proteins functioning in …

Sexual And Asexual Reproductive Characteristics Of The North American Pawpaw [Asimina Triloba (L.) Dunal], Sheri Beth Crabtree

University of Kentucky Master's Theses

The North American Pawpaw [Asimina triloba (L.) Dunal] shows great potential as a new fruit crop. Kentucky State University in Frankfort, Ky. is the site for the USDA National Clonal Germplasm Repository (NCGR) for Asimina species. Both the fruit and the trees themselves are of high value to growers and nursery producers. Pawpaw cultivars are currently propagated by grafting or budding onto seedling rootstock; no method currently exists to clonally propagate pawpaw on its own roots. Three methods of layering were attempted in this study to clonally propagate pawpaw: trench layering, pot layering, and mound layering. Both trench layering …

Molecular Mapping And Identification Of Soybean Fatty Acid Modifier Quantitative Trait Loci, D. L. Hyten Jr., Vincent R. Pantalone, Arnold M. Saxton, Michael E. Schmidt, Carl E. Sams

Department of Agronomy and Horticulture: Faculty Publications

Altering FA content in soybean [Glycine max (L.) Merr.] oil for improved functionality is a research goal of many soybean breeders. Several of the genes that alter palmitic, stearic, oleic, linoleic, and linolenic acids are modifier genes with small effects, causing these FA traits to act as quantitative traits. The objective of this study was to identify modifier FA quantitative trait loci (QTL) in soybean. A recombinant inbred line population was created from two prominent ancestors of currently avail-able U.S. cultivars (Essex and Williams) and grown in five environments. One hundred simple se-quence repeat markers spaced throughout the genome …

Implementation Of A Mitochondrial Mutator, Sally Mackenzie, Ricardo Vilela Abdelnoor

Department of Agronomy and Horticulture: Faculty Publications

Plant MSH1 polynucleotides and polypeptides are described. Also described are methods for the use and modulation of such MSH1 polynucleotides and polypeptides.

Predicting Phenological Development In Winter Wheat, Qingwu Xue, Albert Weiss, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Accurate prediction of phenological development is important in the winter wheat Triticum aestivum agroecosystem. From a practical perspective, applications of pesticides and fertilizers are carried out at specific phenological stages. In crop-simulation modeling, the prediction of yield components (kernel number and kernel weight) and wheat-grain yield relies on accurate prediction of phenology. In this study, a nonlinear multiplicative model by Wang & Engel (WE) for predicting phenological development in differing winter wheat cultivars was evaluated using data from a 3 yr field experiment. In the vegetative phase (emergence to anthesis) the daily development rate (r) was simulated based on the …

Effects Of Vegetation Removal On Native Soil Quality In Eastern Arkansas, Lorena Moreno, Kristofor R. Brye

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

Aboveground vegetation removal practices, such as cutting and baling and burning, can both positively and negatively affect a prairie ecosystem. Burning can stimulate growth and species diversity, but removing vegetation and the nutrients it contains without equal replenishment of those nutrients could cause a steady decline in available soil nutrients. The objective of this study was to evaluate the effects of vegetation removal techniques in a native tallgrass prairie in east-central Arkansas. Soil samples were collected from the top 10 cm in each soil mapping unit that existed in each of three prairie areas that differed by the amount of …

Summaries Of Arkansas Cotton Research 2002, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

The average yield in Arkansas in 2002 was 871 lb lint/acre from 920,000 harvested acres (960,000 planted) for a total of 1.67 million bales at a value of$336.5 million. This yield was second only to the record 877 lb lint/acre achieved in 1994. Last year's crop yield, and the five-year average, on a per acre basis are exceeded in the U.S. Cotton Belt only by California and Arizona. Cotton yields in Arkansas increased steadily during the eighties, but in the last decade yields have leveled off. Furthermore, the last five years have had extreme year-to-year variability in yields, which is …

B.R. Wells Rice Research Studies 2002, R. J. Norman, J.-F. Meullenet

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producing state in the U .S .. representing almost 46% of the total U .S. production and almost 47% of the total acres planted to rice . Rice cultural practices vary across the state and across the U.S. However, due to changing political, environmental, and economic times, the practices arc dynamic. This survey was initiated in 2002 to monitor how the changing times reflect the 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 …

Agroecosystems Analysis From The Grass Roots: A Multidimensional Experiential Learning Course, Mary Wiedenhoeft, Steve Simmons, Ricardo Salvador, Gina Mcandrews, Charles A. Francis, James W. King, David Hole

Department of Agricultural Leadership, Education, and Communication: Faculty Publications

An intensive, experiential travel course in Agroecosystems Analysis was conducted in Iowa, Minnesota, and Nebraska (United States) during summers of 1998 and 1999. The intended student audience was advanced undergraduate and beginning graduate students. Pretravel readings and a week-long series of farm visits, which consisted of in-depth interviews with the farmers and their families, prepared student teams to analyze and evaluate the production, economic, environmental, and social sustainability of 10 farms. Students shared their analyses both orally and in written reports. Based on a multifaceted student evaluation process, we found that participants were highly motivated, strongly engaged with the course …

Crop Updates - 2003 Pulses, M. Harries, R. French, I. Pritchard, R. Beermier, N. Poulish, S. White, M. Seymour, P. White, T. Pope, M. Blyth, L. Young, N. Abbas, J. Plummer, K. Siddique, D. Harris, T. Khan, K. Regan, G. P. Riethmuller, B. Macleod, J. Berger, N. Turner, F. Shan, H. Clarke, P. Smith, M. Baker, H. Dhammu, T. Piper, D. Nicholson, M. Materne, J. Howieson, R. Yates, S. Loss, Z. Rengel, B. Bowden, M. Bolland, J. Croser, A. Harrod, J. Galloway, C. Beeck, J. Wroth, W. Cowling, M. Salam, A. Diggle, R. Jones, B. Coutts, L. Smith, O. Byrne, D. Hardie, J. Ridsill-Smith, H. Sharma, K. Mann, S. Kelly, S. Sharma, H. Hunter, V. Vanstone

Crop Updates

This session covers fifty one papers from different authors

2002 PULSE INDUSTRY HIGHLIGHTS

CONTRIBUTORS

BACKGROUND

2002 REGIONAL ROUNDUP

1.Northern Agricultural Region, M. Harries, Department of Agriculture

2.Central agricultural Region, R. French and I. Pritchard, Department of Agriculture

3.Great Southern and Lakes, R. Beermier, N. Poulish and S. White, Department of Agriculture

4.Esperance Mallee, M. Seymour, Department of Agriculture

PULSE PRODUCTION ECONOMY AND GENETIC IMPROVEMENT

5.Faba Bean, P. White, Department of Agriculture

6.Germplasm evaluation, P. White, T. Pope, M. Harries and M. Seymour, Department of Agriculture

7.Row spacing and sowing rate, M. Seymour, Department …

Crop Updates - 2003 Weeds, Bill Roy, Peter Newman, J. R. Peirce, B. J. Rayner, Kathryn J. Steadman, Gavin P. Bignell, Amanda J. Ellery, Sandy Nedelkos, Ross Chapman, Michelle J. Owen, Simone Dudley, Robert Gallagher, Pippa J. Michael, Julie A. Plummer, Peter Newman, Glenn Adam, Catherine Borger, Abul Hashem, Nerys Wilkins, Sally Peltzer, Alex Douglas, Fran Hoyle, Paul Matson, Michael Walsh, Darren Chitty, David Ferris, Paul Neve, Art Diggle, Patrick Smith, Stephen Powles, David Archer, James Eklund, Frank Forcella, Alister Draper, Rick Llewellyn, Aik Cheam, Siew Lee, David Nicholson, Mike Clarke, Debbie Allen, Harmohinder S. Dhammu, Terry Piper, L. E. Young

Crop Updates

This session covers Thirty four papers from different authors

INTRODUCTION

INTEGRATED WEED MANAGEMENT

IWM system studies/demonstration sites

1. Six years of IWM investigation – what does it tell us? Bill Roy, Agricultural Consulting and Research Services Pty Ltd

2. Long term herbicide resistance site, the final chapter, Peter Newman and Glen Adam, Department of Agriculture

3. Management of skeleton weed (chondrilla juncea) in a cropping rotation in Western Australia, J. R. Peirce and B. J. Rayner, Department of Agriculture

WEED BIOLOGY AND COMPETITION

1. Annual ryegrass seedbanks: The good, the bad and the ugly, Kathryn J. Steadman¹, Amanda …

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Crop Updates - 2003 Oilseeds, Peter Nelson, Graham Walton, Hasan Zaheer, Paul Carmody, J. A. Fortescue, D. W. Turner, Janet Wroth, Wallace Cowling, Anh-Van Pham, R. F. Brennan, Glen Riethmuller, Greg Hamilton, Jo Hawksley, C. M. Zaicou-Kunesch, D. Eksteen, Françoise A. Berlandier, Christiaan Valentine, Owain Edwards, Roger Jones, Brenda Coutts, Lisa Smith, Jenny Hawkes, Ravjit Khangura, Moin Salam, Art J. Diggle, Martin J. Barbetti, Kevin Walden

Crop Updates

This session covers fifteen papers from different authors

ACKNOWLEDGMENTS

VARIETIES

1. Large scale canola varietal evaluation in WA, Peter Nelson, Oilseeds WA

2. Performance of IT and TT canola varieties in the medium and high rainfall agzones of WA 2001-02, Graham Walton, Hasan Zaheer and Paul Carmody, Department of Agriculture

QUALITY

1. Reproductive biology, cotyledon development and oil accumulation in canola, J.A. Fortescue and D.W. Turner, School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia

2. Plant and environmental factors affecting oil concentration in canola – a mini-review, D.W. Turner, School of Plant Biology, …

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Crop Updates 2003 - Cereals, Graham Crosbie, Robert Loughman, Collin Wellings, Greg Shea, Simon Mckirdy, Neil C. Turner, Brenda Shackley, Wal Anderson, Darshan Sharma, Mohammad Amjad, Steve Penny Jr, Melanie Kupsch, Anne Smith, Veronika Reck, Pam Burgess, Glenda Smith, Elizabeth Tierney, Peter Burges, Moin U. Salam, Megan Collins, Art Diggle, Blakely Paynter, Roslyn J. Jettner, Kevin Young, Jocelyn Ball, Natasha Littlewood, Lucy Anderton, Irene Waters, Tim Setter, Jeff Russell, Reg Lance, Chengdao Li, Sue Broughton, Michael Jones, Grace Zawko, Keith Gregg, Stephen Loss, Frank Ripper, Ryan Guthrie, Daniel Bell, Patrick Gethin, Narelle Hill, Laurence Caeslake, Vivien Vanstone, Sean Kelly, Helen Hunter, Christopher R. Newman

Crop Updates

This session covers twenty one papers from different authors:

PLENARY

1. Recognising and responding to new market opportunities in the grains industry, Graham Crosbie, Manager, Grain Products Research, Crop Breeding, Plant Industries, Department of Agriculture

2. Stripe rust – where to now for the WA wheat industry? Robert Loughman¹, Colin Wellings² and Greg Shea¹¹Department of Agriculture, ²University of Sydney Plant Breeding Institute, Cobbitty (on secondment from NSW Agriculture)

3. Benefits of a Grains Biosecurity Plan, Dr Simon McKirdy, Plant Health Australia, Mr Greg Shea, Department of Agriculture

4. Can we improve …

Intsormil 2003 Annual Report, John M. Yohe, Thomas Crawford Jr., Kimberly Christiansen, Joan Frederick

INTSORMIL Impacts and Bulletins

From 1980 to 1999, according to the Food and Agriculture Organization of the United Nations (FAO), the number of food-insecure people in developing countries fell from 920 million to about 800 million, yet in 2003, the International Food Policy Research Institute declared that "without significant changes in policies, public investments, and institutions, we simply will not achieve the 1996 World Food Summit goal-reaffirmed at the 2000 Millennium Summit and again last year at the World Food Summit: five years later of reducing the number of our fellow human beings who are food insecure by at least half by no later …

Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox

Inquiry: The University of Arkansas Undergraduate Research Journal

In addition to having numerous applications and pharmaceuticals, terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by insects. Sequences of DNA encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicago truncatula leaves, were selected from an expressed sequence tag (EST) data base. The cDNA clones were used as radio-labeled probes to analyze gene expression in leaves treated with factors known to trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl jasmonate (meJA) …