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Agronomy and Crop Sciences

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Articles 9541 - 9570 of 9732

Full-Text Articles in Plant Pathology

Crop Updates 2000 - Cereals Part 2, Debbie Thackray, Jenny Hawkins, Roger Jones, Dominie Wright, Peter Carlton, Jat Bhathal, Robert Loughman, K. Jayasena, J. Majewski, S. Kelly, G. Holloway, N, Venn, D. Diepeveen, Brenda Shackley, Darshan Sharma, Wal Anderson, Mohammad Amjad, Vanessa Dooley, Peter Burgess, Ashley Bacon, Frances Hoyle, Keith Devenish, Mathew Appelbee, Mohommed Hamza, Steven Mccoy, Steven Penny Feb 2000

Crop Updates 2000 - Cereals Part 2, Debbie Thackray, Jenny Hawkins, Roger Jones, Dominie Wright, Peter Carlton, Jat Bhathal, Robert Loughman, K. Jayasena, J. Majewski, S. Kelly, G. Holloway, N, Venn, D. Diepeveen, Brenda Shackley, Darshan Sharma, Wal Anderson, Mohammad Amjad, Vanessa Dooley, Peter Burgess, Ashley Bacon, Frances Hoyle, Keith Devenish, Mathew Appelbee, Mohommed Hamza, Steven Mccoy, Steven Penny

Crop Updates

This session covers twenty papers from different authors:

DISEASE

1. Forecasting aphid and virus risk in cereals, Debbie Thackray, Jenny Hawkes and Roger Jones, Agriculture Western Australia and Centre for Legumes in Mediterranean Agriculture

2. Cereal Diagnostics, Dominie Wright, Agriculture Western Australia

3. The economic returns from spraying for leaf rust in the central wheatbelt in 1999, Peter Carlton, Trials Coordinator, Elders Limited

4. Impact and Management of Yellow Spot and Leaf Rust in the Northern Agricultural Region, Jat Bhathal and Robert Loughman, Agriculture Western Australia

5. Leaf disease management in wheat and barley in the southern …


Bulletin 4406a - Fungal Diseases Of Canola In Western Australia, Martin Barbetti, Ravjit Khangura Feb 2000

Bulletin 4406a - Fungal Diseases Of Canola In Western Australia, Martin Barbetti, Ravjit Khangura

Bulletins 4000 -

GRDC - Grains Research & Development Corporation.

There has been dramatic growth in the canola industry in Western Australia, from 35,000 hectares in 1993 to 920,000 hectares in 1999. Along with this expansion in the area sown the incidence and severity of various fungal diseases have also increased, especially blackleg. This Bulletin describes the most important and most prevalent fungal diseases of canola in Western Australia.


Basic Biotechnology, Jennifer Flak, Julie Albrecht Jan 2000

Basic Biotechnology, Jennifer Flak, Julie Albrecht

Plant and Soil Sciences eLibrary

An introduction to traditional cross-breeding and genetic engineering of plants, and to biotechnology.

Objectives - Basic Biotechnology

After completing Nutrition Basic Biotechnology, participants should be able to:

  • Describe one similarity between traditional cross-breeding and genetic engineering of plants.
  • Give two limitations that are encountered with traditional cross-breeding of plants.
  • Explain why genetic engineering is not limited in the same way as traditional cross-breeding.
  • Define biotechnology in broad terms.
  • List three plant applications of biotechnology.
  • List the three areas of nutritional profiles that have been improved with biotechnology.

Modules:


Sistem Diagnosis Penyakit Tanaman Padi (Pakar Padi), Jin Gee Tee Jan 2000

Sistem Diagnosis Penyakit Tanaman Padi (Pakar Padi), Jin Gee Tee

Student Works (2000-2009)

Beras adalah makanan utama rakyat Malaysia. Banyak kajian dan penyelidikan dibuat untuk meningkatkan hasil tanaman padi. Di antaranya termasuklah mengkaji cara-cara kawalan serangga perosak dan kerja-kerja diagnosis penyakit tanaman padi. Maklumat-maklumat daripada hasil kajian harus disimpan dengan baik supaya kerja diagnosis dapat dijalankan dengan lebih lancar. Memandangkan keperluan ini, satu sistem berkomputeran yang menyimpan data data mengenai tanaman padi adalah penting dan dijangka akan memberi bantuan dalam pengurusan dan kerja-kerja diagnosis. Ini telah membawa kepada idea untuk membangunkan satu sistem diagnosis penyakit bagi tanaman padi. Sistem Diagnosis Penyakit Tanaman Padi, diberikan nama Pakar Padi adalah satu sistem berpangkalan komputer yang …


Agriculture Western Australia's Centre For Cropping Systems - Northam, Agriculture Western Australia Aug 1999

Agriculture Western Australia's Centre For Cropping Systems - Northam, Agriculture Western Australia

Grain and other field crops published reports

Agriculture Western Australia's Centre for Cropping Systems in York Road, Northam, was established as a centre of excellence for research, development and extension into cropping systems.

Its role is to stimulate the contribution of ideas from individuals, groups and organisations with an interest in research, development, and extension relating to innovative, profitable and sustainable crop-based farming systems.

The Centre for Cropping Systems is part of a regional network with strong links to Agriculture Western Australia's Crop Improvement Institute based at South Perth, the Dryland Research Institute at Merredin and the Avondale Research Fann at Beverley. It also links with universities …


Cereal Rust Diseases And Their Management, 1999, Rob Dickie, Rob Loughman, Jat Bhathal Jun 1999

Cereal Rust Diseases And Their Management, 1999, Rob Dickie, Rob Loughman, Jat Bhathal

Technical Bulletins

• Wheat leaf rust (Puccinia recondita f.sp. tritici) is specific to wheat and triticale. A single pathotype (designated 104-1,2,3,(6),(7),11) has dominated in W.A. since 1990. Wheat leaf rust regularly survives the non-cropping summer in varying quantities, usually sufficient to occur at least to a limited extent (particularly in southern regions) each year. The disease develops rapidly between 15 and 22°C when moisture (including dew) is non-limiting. The highest yield increase attributed directly to control of leaf rust in W.A. is 37 per cent. However the disease is synergistically damaging in combination with septoria leaf blotches. In Esperance in …


Crop Updates 1999 - Oilseeds, Paul Carmody, Rick Madin, David Bowran, Martin Barbetti, Ravjit Khangura, Graham Walton, Phil Parker, Francoise Berlandier, Linnet Cartwright, Ping Si, Nick Galwey, David Turner, Wayne Pluske, Roger Jones, Brenda Coutts, Bill Bowden, Isabel Arevalo-Vigne, Jeff Russell, Syed H. Zaheer, Andrew Simon, Art Diggle, Dave Eksteen, Arjen Ryder, Bill Crabtree, Serena Wyatt, Jim Baily Feb 1999

Crop Updates 1999 - Oilseeds, Paul Carmody, Rick Madin, David Bowran, Martin Barbetti, Ravjit Khangura, Graham Walton, Phil Parker, Francoise Berlandier, Linnet Cartwright, Ping Si, Nick Galwey, David Turner, Wayne Pluske, Roger Jones, Brenda Coutts, Bill Bowden, Isabel Arevalo-Vigne, Jeff Russell, Syed H. Zaheer, Andrew Simon, Art Diggle, Dave Eksteen, Arjen Ryder, Bill Crabtree, Serena Wyatt, Jim Baily

Crop Updates

This article contains eighteen papers

  1. INTRODUCTION, Paul Carmody, Agriculture Western Australia

PLENARY SESSION

  1. Transgenic canola in Western Australia: Outlook and challenges, Phil Salisbury, University of Melbourne

  2. Farming system issues for herbicide tolerant canola, Rick Madin, Rick Madin and Associates, David Bowran, Agriculture Western Australia

  3. Beating blackleg in 1999, Martin Barbetti, Ravjit Khangura, Paul Carmody, Graham Walton, Agriculture Western Australia

  4. The Mustard Industry in Australia – Opportunities for a new oilseed, Phil Parker, NSW Agriculture

  5. Management of blackleg with fungicides, Ravjit Khangura and Martin Barbetti, Agriculture Western Australia

  6. Effect of aphid feeding …


Crop Updates 1999 - Lupins, Greg Shea, Geoff Thomas, Mark Sweetingham, Bill O'Neill, Wallace Cowling, Bevan Buirchell, Hua'an Yang, David Luckett, Allan Brown, John Hamblin, Joanne E. Barton, Kedar Adhikari, Nick Galwey, Miles Dracup, Bob French, Debbie Thackray, Roger Jones, Brenda Coutts, Narelle Reeve, Y. Cheng, R. A.C. Jones, Francoise Berlandier, Linnet Cartwright, James Fisher, Art Diggle, Bill Bowden, Chris Gazey, Luigi Morsechi, Terry Piper, Peter Newman, Dave Nicholsen, Mohammad Amjad, Glen Riethmuller, Ron Javis, Paul Blackwell, C. L. White Feb 1999

Crop Updates 1999 - Lupins, Greg Shea, Geoff Thomas, Mark Sweetingham, Bill O'Neill, Wallace Cowling, Bevan Buirchell, Hua'an Yang, David Luckett, Allan Brown, John Hamblin, Joanne E. Barton, Kedar Adhikari, Nick Galwey, Miles Dracup, Bob French, Debbie Thackray, Roger Jones, Brenda Coutts, Narelle Reeve, Y. Cheng, R. A.C. Jones, Francoise Berlandier, Linnet Cartwright, James Fisher, Art Diggle, Bill Bowden, Chris Gazey, Luigi Morsechi, Terry Piper, Peter Newman, Dave Nicholsen, Mohammad Amjad, Glen Riethmuller, Ron Javis, Paul Blackwell, C. L. White

Crop Updates

This article contains twenty three papers

1998 LUPIN HIGHLIGHTS

LUPIN ANTHRACNOSE

1. Anthracnose overview, Greg Shea, Geoff Thomas and Mark Sweetingham, Agriculture Western Australia

2. Anthracnose – Critical seed infection levels for resistant and susceptible varieties, Geoff Thomas, Mark Sweetingham, Bill O'Neill and Greg Shea, Agriculture

Western Australia

3. Fungicide seed treatment for anthracnose and brown spot control in lupin, G. Thomas and M. Sweetingham, Agriculture Western Australia

LUPIN BREEDING AND AGRONOMY

4. Anthracnose resistance in lupins – an innovative Australian research effort 1996-1998, Wallace Cowling1'2, Bevan Buirchell1,2 Mark Sweetinqham1,2, Hua'an Yang2, …


Crop Updates 1999 - Cereals, Len W. Broadbridge, Doug Abrecht, D. Bakker, Greg Hamilton, Cliff Spann, Doug Rowe, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Bill Bowden, Ross Brennan, Reg Lunt, Senthold Asseng, Cherie Rowles, Simon Bedbrook, Chris Gazey, Mike Bolland, Garren Knell, Lyn Abbott, Zed Rengel, Wayne Pluske, Erin Cahill, Bill Crabtree, Matthew Evans, Tim Nielsen, Jat Bhathal, Rob Loughman, D. Rasmussen, Roger A C Jones, Sean Kelly, Ian Riley, Sharyn Tayor, Vivien Vanstone, Dominie Wright, Debbie Thackray, Simon Mckirdy, George Yan, Robin Wilson, Iain Barclay, Robin Mclean, Dean A. Diepeveen, Bill Lambe, Wal Anderson, Brenda Shackley, Mechelle Owen, Peter Burgess, Ben Curtis, Mohammed A. Hamza, Jamie Henderson, Frank Boetel, Alfredo Impiglia, Frances Hoyle, Darshan Sharma, Pierre Fievez, Blakely Paynter, Glenn Macdonald, Kevin Young, Andrew Blake, Keith Devenish, P J. Dolling, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Angelo Loi, Brad Nutt, Rochelle Mcrobb, David Webb, Andrew Mcrobb, Clinton K. Revell, James Ridsdill-Smith, Celia Pavri, David Tennant, Darryl Mclements, Ross Thompson, Mike Ewing, Tim Woodburn, Paul Yeoh, James Fisher, Art Diggle, Mark Whitten, Andrew Rate, Paul Carlile, Ed Blanchard, Bevan Buirchell, Lorraine Osborne, Tress Walmsley, Terry Piper, Cameron Weeks, Michael Dodd, Amanda Falconer, Caroline Peek, Glenn Adam, Camray Gethin, Richard Guinness, Daniel Fels, Andrew Rintoul, Mal Lamond, Roger Tapp, Craig White Feb 1999

Crop Updates 1999 - Cereals, Len W. Broadbridge, Doug Abrecht, D. Bakker, Greg Hamilton, Cliff Spann, Doug Rowe, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Bill Bowden, Ross Brennan, Reg Lunt, Senthold Asseng, Cherie Rowles, Simon Bedbrook, Chris Gazey, Mike Bolland, Garren Knell, Lyn Abbott, Zed Rengel, Wayne Pluske, Erin Cahill, Bill Crabtree, Matthew Evans, Tim Nielsen, Jat Bhathal, Rob Loughman, D. Rasmussen, Roger A C Jones, Sean Kelly, Ian Riley, Sharyn Tayor, Vivien Vanstone, Dominie Wright, Debbie Thackray, Simon Mckirdy, George Yan, Robin Wilson, Iain Barclay, Robin Mclean, Dean A. Diepeveen, Bill Lambe, Wal Anderson, Brenda Shackley, Mechelle Owen, Peter Burgess, Ben Curtis, Mohammed A. Hamza, Jamie Henderson, Frank Boetel, Alfredo Impiglia, Frances Hoyle, Darshan Sharma, Pierre Fievez, Blakely Paynter, Glenn Macdonald, Kevin Young, Andrew Blake, Keith Devenish, P J. Dolling, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Angelo Loi, Brad Nutt, Rochelle Mcrobb, David Webb, Andrew Mcrobb, Clinton K. Revell, James Ridsdill-Smith, Celia Pavri, David Tennant, Darryl Mclements, Ross Thompson, Mike Ewing, Tim Woodburn, Paul Yeoh, James Fisher, Art Diggle, Mark Whitten, Andrew Rate, Paul Carlile, Ed Blanchard, Bevan Buirchell, Lorraine Osborne, Tress Walmsley, Terry Piper, Cameron Weeks, Michael Dodd, Amanda Falconer, Caroline Peek, Glenn Adam, Camray Gethin, Richard Guinness, Daniel Fels, Andrew Rintoul, Mal Lamond, Roger Tapp, Craig White

Crop Updates

This article covers sixty papers

FOREWORD

ACKNOWLEDGMENTS

PLENARY PAPERS

1. Western Australia’s climate: trends and opportunities, Len W. Broadbridge, Director, Bureau of Meterorology

2. Managing seasonal variations in agriculture, Dr Doug Abrecht, Director, Dryland Research Institute, Merredin

CROP ESTABLISHMENT

3. Soil management to prevent waterlogging on duplex soils in the Great Southern, D. Bakker, Greg Hamilton, Cliff Spann and Doug Rowe, Agriculture Western Australia

4. The influence of no-till and press wheels on crop production for heavy soils, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Greg Hamilton, Agriculture

Western Australia

NUTRITION

5. Fertiliser nitrogen, applied late, needs …


Farm Operator Satisfaction With Retail Pesticide Suppliers In The Arkansas Delta, Bruce L. Dixon, Damon Mckelvey, Travis Rogers, Frank L. Farmer, Daniel M. Settlage Feb 1999

Farm Operator Satisfaction With Retail Pesticide Suppliers In The Arkansas Delta, Bruce L. Dixon, Damon Mckelvey, Travis Rogers, Frank L. Farmer, Daniel M. Settlage

AAES Research Reports and Research Bulletins

Two hundred ninety farm operators in the three easternmost crop reporting districts in Arkansas responded to a mail survey in November 1996 about their preferences and satisfaction with retail pesticide suppliers.Results show most farmers are quite satisfied with their main retail pesticide supplier, although 55.5% of the farm operators used more than one retail pesticide supplier in 1996. Users of multiple suppliers were less satisfied with their suppliers than those using only one supplier. Availability of certain pesticides was the most frequently mentioned reason for using multiple suppliers. Several attributes were important in selecting the main supplier with reputation being …


Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell Jan 1998

Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell

Biosecurity published reports

Second edition.

The Northern Australia Quarantine Strategy (NAQS) was established in 1989 as an outcome of a major evaluation of quarantine in Australia (AGPS 1987, 1988). NAQS activities include surveying for weeds,insect pests and diseases of plants; and pests and diseases of animals in northern Australia, Papua New Guinea and Indonesia. The primary goal is to provide early detection and warning of new quarantine threats or incursions.

A targetted approach was adopted for all pests, diseases and weeds. For each category of pest, experts in the discipline compiled lists of organisms not known from Australia but known to occur in …


Seasonal Occurrence Of Rice Yellow Mottle Virus In Lowland Rice In Côte D’Ivoire, E. A. Heinrichs, A. A. Sy, S. K. Akator, I. Oyediran Jan 1997

Seasonal Occurrence Of Rice Yellow Mottle Virus In Lowland Rice In Côte D’Ivoire, E. A. Heinrichs, A. A. Sy, S. K. Akator, I. Oyediran

Department of Entomology: Faculty Publications

Monthly plantings of the rice variety Bouaké 189 were made under lowland irrigated conditions, to obtain information on the phenological and seasonal occurrence of pests and diseases on the West African Rice Development Association (WARDA) research farm near Bouaké, Côte d’Ivoire. Regular sampling of insect pests and observations on rice yellow mottle virus (RYMV) disease infection throughout the year provided information on the occurrence of RYMV and potential insect vectors. RYMV incidence and grain yields varied depending on planting date, and for a given planting date, varied from one year to another. There was no evidence that RYMV incidence increases …


Effect Of Media Constituents On In Vitro Culturing Of Cowpea (Vigna Unguiculata) Shoot Tip And Leaf Disk Explants, Mohanjeet S. Brar, Edwin J. Anderson, Teddy E. Morelock, Ronald W. Mcnew Jan 1997

Effect Of Media Constituents On In Vitro Culturing Of Cowpea (Vigna Unguiculata) Shoot Tip And Leaf Disk Explants, Mohanjeet S. Brar, Edwin J. Anderson, Teddy E. Morelock, Ronald W. Mcnew

Journal of the Arkansas Academy of Science

Cowpea is an important legume food crop that is commonly grown in Arkansas and numerous other southern states. The application of biotechnological approaches for the improvement of U.S. cowpea genotypes is currently not possible due to the lack of a regeneration and transformation system. Therefore, the first priority of our research efforts is the development of a plant regeneration system that will facilitate plant transformation studies. In an effort to optimize the media requirements for tissue culturing cowpea, we evaluated the in vitro response of shoot tip and leaf disk explants to various levels of Murashige and Skoog (MS) macro …


Coming To Grips With Eradu-Patch Of Lupins, Bill Macleod, Mark Sweetingham Jan 1995

Coming To Grips With Eradu-Patch Of Lupins, Bill Macleod, Mark Sweetingham

Journal of the Department of Agriculture, Western Australia, Series 4

Investigations by Bill MacLoud and Mark Sweetingham have confirmed that Eradu-patch of lupins is caused by apreviously undescribed fungal pathogen,\.

They have developed strategies to minimise the spread of patches but choices are limited for control in lupin crops


Cucumber Mosiac Virus In Lupins, Annette Bwye, Roger Jones, Wayne Proudlove Jan 1995

Cucumber Mosiac Virus In Lupins, Annette Bwye, Roger Jones, Wayne Proudlove

Journal of the Department of Agriculture, Western Australia, Series 4

Cucumber mosaic virus is a threat to lupin crops from Geraldton to Esperance, particularly to those growing in areas receiving more than 400 mm average annual rainfall. The disease markedly decreases grain yield in narrow-leafed and yellow lupins but doesnot infect albus or sandplain lupins. Worldwide , after bean yellow mosaic virus, cucumber mosaic virus is the second most important virus affecting lupins. Annette Bwye, Roger Jones and Wayne Proudlove outline the symptoms, spread and management of this serious disease.


Pulses : Profitable New Crops For The Wheatbelt, Kadambot Siddique, Stephen Loss, Ian Pritchard Jan 1995

Pulses : Profitable New Crops For The Wheatbelt, Kadambot Siddique, Stephen Loss, Ian Pritchard

Journal of the Department of Agriculture, Western Australia, Series 4

Narrow-leafed lupins have beeb produced on sandy acid soils throughout the wheatbelt for more than two decades. However, the wheatbelt contains large areas ofsoilsnot suited to narrow-leafed lupins. For several years reasearchers have been examining alternatives to narrow-leafed lupins for these soils.

Kadambot Siddique, Stephen Loss and Ian Prichard look at production of these new grain legumes, known as pulses.


Bulletin 4294 - Virus Diseases Of Lupins, Roger Jones Dec 1994

Bulletin 4294 - Virus Diseases Of Lupins, Roger Jones

Bulletins 4000 -

Two virus diseases pose a serious threat to lupins. These are caused by cucumber mosaic virus (CMV), which induces diseases in narrow-leafed and yellow lupins, and bean yellow mosaic virus (BYMV), which infects all types of cultivated lupins. The effects of the viruses on lupin plants range from subtle colour changes and leaf distortion to leaf shedding, stunting and death. Seed production is decreased or prevented. There is no cure, but lupin crops can be managed to minimise both virus spread and its persistence from year to year.

CMV and BYMV occur within all tissues in the plant, but do …


Barley Yellow Dwarf Virus In Cereals, Simon Mckirdy, Roger Jones Jan 1993

Barley Yellow Dwarf Virus In Cereals, Simon Mckirdy, Roger Jones

Journal of the Department of Agriculture, Western Australia, Series 4

Worldwide, barley yellow dwarf virus (BYDV) is the most widespread and damaging virus disease of cereals. It infects wheat, barley, oats and grasses and is transmitted by several aphid species. The virus is not seed-borne and to persist from one growing season to the next it must survive in over-summering grasses.

Barley yellow dwarf virus decreases grain yield and also causes shrivelled grain. Yield loss is greatest from infection early in the growing season.


Role Of Endophytes In Tall Fescue, E. L. Piper, C. P. West Jan 1993

Role Of Endophytes In Tall Fescue, E. L. Piper, C. P. West

Journal of the Arkansas Academy of Science

Tall fescue (Festuca arundinacea Schreb.) is the most commonly grown cool season grass used for pastures in Arkansas. Most tall fescue contains a fungal endophyte (Acremonium coenophialum Morgan-Jones & Gams), which causes fescue toxicosis in livestock and costs cattle producers millions of dollars annually in lost production. Endophyte presence is known to reduce wild mammal populations in areas where tall fescue is prevalent. The endophyte spends its entire life cycle within the plant and is transmitted through the seed. The association is mutualistic with the plant providing nutrients for the endophyte and the endophyte conferring drought, insect, and nematode resistance …


Pesticide Use On Sweet Corn Grown In Connecticut: 1990, James L. Turner Ii, Candace L. Bartholomew Sep 1992

Pesticide Use On Sweet Corn Grown In Connecticut: 1990, James L. Turner Ii, Candace L. Bartholomew

Storrs Agricultural Experiment Station

No abstract provided.


Stubble Retention And Leaf Disease In Lupin And Cereal Crops, Mark Sweetingham, Robert Loughman, Ron Jarvis Jan 1992

Stubble Retention And Leaf Disease In Lupin And Cereal Crops, Mark Sweetingham, Robert Loughman, Ron Jarvis

Journal of the Department of Agriculture, Western Australia, Series 4

Retention of cereal stubbles can reduce leaf disease in lupins but increase leaf disease in cereals. The extent of cereal disease carry-over in stubbles depends on the locality and whether multiple cropping or crop rotation is practised


Sterol Composition Of The Corn Root Lesion Nematode, Pratylenchus Agilis, And Corn Root Cultures, David J. Chitwood, William R. Lusby Jan 1991

Sterol Composition Of The Corn Root Lesion Nematode, Pratylenchus Agilis, And Corn Root Cultures, David J. Chitwood, William R. Lusby

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Sterols from mixed stages of the com root lesion nematode, Pratylenchus agilis, and uninfected corn root cultures were analyzed by gas chromatography-mass spectrometry. Twenty-eight sterols were identified in P. agilis, including nine not previously detected in nematodes. The major sterols were 24-ethylcholest-22-enol, 24-ethylcholesta-5,22-dienol, 24-methy1cholestanol, 24-ethylcholestanol, isofucostanol, and 24-ethylcholesterol. The principal corn root sterols were 24-ethylcholesta-5,22-dienol, 24-methylcholesterol, 24-ethylcholesterol, isofucosterol, and cycloartenol. Therefore, the major metabolic transformation of sterols by P. agilis was saturation of the sterol nucleus. In addition, very small amounts of 4α-methylsterols were biosynthesized by P. agilis. The 4-methylation pathway is unique to nematodes and was …


Origin And Evolution Of Defective Interfering Rnas Of Tomato Bushy Stunt Virus, David A. Knorr, Thomas Jack Morris Jan 1991

Origin And Evolution Of Defective Interfering Rnas Of Tomato Bushy Stunt Virus, David A. Knorr, Thomas Jack Morris

School of Biological Sciences: Faculty Publications

Viruses with defective genomes have been identified in association with virtually every major family of viruses and have been widely utilized as tools for investigating virus functions in animal cell culture systems (Perrault, 1981). It is generally thought that defective interfering viruses (DIs) arise through deletion, rearrangement, or recombination of a competent viral genome. DIs tack the ability for independent existence relying on their parental helper viruses to supply factors required for replication, maturation, and/or encapsidation (Huang and Baltimore, 1977). The interference attributed to DIs is thought to result from competition with the helper virus for factors required in trans …


Pesticide Use On Crops In Nebraska - 1987, Maurice Baker, Nancy Peterson, Shripat T. Kamble Aug 1990

Pesticide Use On Crops In Nebraska - 1987, Maurice Baker, Nancy Peterson, Shripat T. Kamble

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This is the third and most comprehensive study of pesticide use on crops in Nebraska. The first was completed in 1978 and the second one in 1982. The first study indicated that approximately 25 million pounds (11.34 million kg) of active ingredients were used on the major crops in Nebraska. This increased to approximately 30.2 million pounds (13.7 million kg) in 1982. The USDA requires accurate information to meet their responsibilities. Thus, this survey was undertaken to determine: 1) the use of pesticides on crops, pasture and rangeland and 2) to identify pest management practices.


Coping With Brown Spot And Root Rots Of Lupins, Mark Sweetingham Jan 1990

Coping With Brown Spot And Root Rots Of Lupins, Mark Sweetingham

Journal of the Department of Agriculture, Western Australia, Series 4

There is increasing concern that brown spot and root diseases may limit the long term viability of lupin cultivation in close rotations in the agricultural areas of Western Australia. Research has found several useful strategies to reduce the impact of brown spot and Pleiochaeta root rot so that losses can be kept to a minimum. Rhizoctonia has proved more difficult to combat. Although less widespread than Pleiochaeta, it has caused severe losses and appears to be increasing in incidence, particularly in the northern wheatbelt. Research has vastly expanded our knowledge of the strains of Rhizoctonia present in our soils and …


Managing Diseases Of Alfalfa, Paul C. Vincelli, Garry D. Lacefield, Jimmy C. Henning Jan 1990

Managing Diseases Of Alfalfa, Paul C. Vincelli, Garry D. Lacefield, Jimmy C. Henning

Agriculture and Natural Resources Publications

Alfalfa can be a vigorous and productive forage crop for Kentucky farmers. Like all farm crops, however, alfalfa is subject to infectious diseases that can limit forage production. Managing these diseases is an important part of economical alfalfa production.

Alfalfa diseases can cause reduced forage yield, reduced forage quality, and decreased stand persistence. Sometimes, the effects of infectious diseases can be dramatic, such as sudden stand loss in a fall-seeded crop caused by Sclerotinia crown and stem rot. Often, the effects of diseases on alfalfa are more subtle but no less important. For example, alfalfa plants with Phytophthora root rot …


Studies On The Giant Mealie Witchweed, Striga Forbesii Benth., In Zimbabwe, David Allen Knepper Oct 1989

Studies On The Giant Mealie Witchweed, Striga Forbesii Benth., In Zimbabwe, David Allen Knepper

Biological Sciences Theses & Dissertations

Of the seven species of Striga found in Zimbabwe, S. forbesii Benth. is currently the most destructive in terms of crop damage. Owing to its limited occurrence worldwide as a pest of crops, relatively little work has been done on this species.

Striga forbesii has been found to be a consistent problem on both maize and sorghum in the Hunter's Road District of KweKwe, Zimbabwe. Results of a pot study and field observations, indicate S. forbesii can successfully parasitize Urochloa panicoides Beauv., Sorghum arundinaceum (Desv.) Stapf, and Rottboellia cochinchinensis (L.) L.f., all of which are widespread weeds of arable land. …


Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti Sep 1989

Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti

Bulletins 4000 -

Subterranean clover (Trifolium subterraneum L.) is the most important annual pasture legume in Western Australia, forming the basis of some 6.5 million ha of annual pastures. The success of subterranean clover may be attributed to its ability to increase soil fertility as a consequence of nitrogen fixed, to withstand heavy grazing, to control soil erosion and, with some cultivars, to tolerate waterlogging. Fungal diseases have been a major limitation to the productivity of subterranean clover, affecting both the amount of plant matter and the quantity of seed produced.

Annual medic (Medicago spp., in particular M. polymorpha L.) is also an …


Breeding Phomopsis-Resistant Lupins, John Sylvester Gladstones Jan 1989

Breeding Phomopsis-Resistant Lupins, John Sylvester Gladstones

Journal of the Department of Agriculture, Western Australia, Series 4

The release of Gungurru and Yorrel lupins marks the coming of age of the narrow-leafed lupin as a crop plantt. These are the first cultivars of the species th have substantial resistance to Phomopsis stem blight, which will make the stubbles much safer for grazing stock.

This article describes the new lupins, their background, and how they were bred. It also acknowledges the contributions of colleagues who helped in important ways.


Erosion Potential Of Phomopsis-Resistant Lupins, D J. Carter, Paul Findlater Jan 1989

Erosion Potential Of Phomopsis-Resistant Lupins, D J. Carter, Paul Findlater

Journal of the Department of Agriculture, Western Australia, Series 4

During lupin harvesting, up to 20 per cent of the grain remains on the ground. This non-harvested or pilt grain is a valuable feed for sheep during early summer because the pods, leaf and stem generally provide little nutrient in the stubnbles. In addition, the more efficient the weed control, the less valuable are the stubbles.

The disease lupinosis caused by Phomopsis leptostromiformis restricts the amount of grazing from the lupin stubbles, and hence the risk of wind-erosion of stubble paddocks.

However, the introduction of lupin varieties moderately resistant to Phomopsis and with reduced potential to cause lupinosis means that …