Plant Pathology Commons^™

Investigating Birds As Dispersal Vectors Of Litylenchus Crenatae Subsp. Mccannii (Anguinidae), The Nematode Associated With Beech Leaf Disease, Spencer Rock Parkinson

Graduate Theses, Dissertations, and Problem Reports

Beech leaf disease (BLD) is an emerging forest pathogen primarily affecting American beech (Fagus grandifolia, Ehrh.) in North America and has been attributed to tree mortality of sapling sized trees within five to seven years of infection. Symptoms typically occur in regenerating American beech thickets sprouting from roots of trees killed by beech bark disease. Scientists first observed BLD in Ohio in 2012 and currently has spread to 15 states in the USA and one Canadian province. The nematode Litylenchus crenatae subsp. mccannii (Lcm) is highly associated with BLD symptoms, interveinal chlorosis and defoliation of leaves, and is currently …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Using Condensed Tannin To Mitigate Tall Fescue Toxicosis, Ally Jo Grote

Graduate Theses and Dissertations

Endophyte-infected (Neotyphodium coenophialum) tall fescue, [Schedonorus arundinaceus (Shreb.)] produces ergot alkaloids. Condensed tannins could bind to ergot alkaloids and render them ineffective. The first objective was to improve the health of sheep offered endophyte-infected tall fescue by binding toxins in the rumen with condensed tannins. Non-toxic novel-endophyte infected tall fescue (NE) or toxic endophyte-infected tall fescue forage was harvested, baled at targeted moisture of 55%, wrapped within 8 hours of baling with 2 layers of net wrap and 20 layers of plastic, and ensiled for at least 60 days. Prior to feeding, forages were chopped and packed into plastic trash …

Primary Industries Development Research Highlights 2021, Department Of Primary Industries And Regional Development, Tim Scanlon

Books & book chapters

The Primary Industries Development Research Highlights 2021 showcases the breadth and depth of the Department of Primary Industries and Regional Development’s research and development activities over the past several years.

Stories featured in Research Highlights 2021 stem from about 60 (of 140) current and recently-completed projects undertaken by the Department of Primary Industries and Regional Development’s (DPIRD) 1100 scientists, technical experts and economists throughout the State.

Explore our Research Highlights 2021.

The publication demonstrates the innovative and applicable research that DPIRD and its collaborators and investment partners deliver to Western Australia.

Download the Research Highlights 2021 here. Alternatively, …

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …

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 …

Cost-Benefit Analysis Of A Genetic Marker On Cow-Calf Operations Differentiated By Pasture And Breed, Josh C. Crystal, Michael P. Popp, Nathan P. Kemper, Charles F. Rosenkrans Jr.

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

Genetic sequencing in beef cattle (Bos taurus L.) is expected to aid producers with selecting breeding stock. Using data from experimental trials conducted with Angus, Brahman, and their reciprocal cross, the single nucleotide polymorphism (SNP) P450 C994G marker expression was investigated for use in selecting genetics suited to grazing endophyte-infected tall fescue (Festuca arundinacea Schreb. L.) compared to bermudagrass (Cynodon dactylon L.) pasture. The study is unique in the sense that actual cow-calf breeding failure rates (open cows were not culled) were tracked from 1991 to 1997 on herds that were bred to calf in spring and were either exposed …

Description Of Mesocriconema Ericaceum N. Sp. (Nematoda: Criconematidae) And Notes On Other Nematode Species Discovered In An Ericaceous Heath Bald Community In Great Smoky Mountains National Park, Usa, Thomas O. Powers, Peter Mullin, Rebecca Higgins, Timothy Harris, Kirsten S. Powers

Department of Plant Pathology: Faculty Publications

A new species of Mesocriconema and a unique assemblage of plant-parasitic nematodes was discovered in a heath bald atop Brushy Mountain in Great Smoky Mountains National Park. Mesocriconema ericaceum n. sp., a species with males, superficially resembles M. xenoplax. DNA barcoding with the mitochondrial COI gene provided evidence of the new species as a distinct lineage. SEM revealed significant variability in arrangement of labial submedian lobes, plates, and anterior and posterior annuli. Three other nematodes in the family Criconematidae were characterized from the heath bald. Ogma seymouri, when analyzed by statistical parsimony, established connections with isolates from north-eastern Atlantic …

Why I Love Grasshopper Sparrows, Michele Patenaude

UVM Libraries Conference Day

Since 2001, Michele (a library circulation supervisor in her day job) has conducted a summer breeding-bird survey of Grasshopper Sparrows at Camp Johnson in Colchester, VT. Named Grasshopper Sparrows because their breeding call sounds like a grasshopper, this little brown bird is endemic to certain types of scrubby grasslands which are becoming more scarce in the Northeast. The Grasshopper Sparrow is also declining and the species is not on the list of Vermont Endangered Birds. Come to this presentation and learn about the bird, how Michele surveys them, why they are endangered, and why Michele loves these quiet, little brown …

Incorporating Sheep Into Dryland Grain Production Systems Iii. Impact On Changes In Soil Bulk Density And Soil Nutrient Profiles, P. G. Hatfield, H. B. Goosey, T. M. Spezzano, Sue L. Blodgett, Andrew W. Lenssen, R. W. Kott, C. B. Marlow

Andrew W. Lenssen

Changes in soil bulk density and soil nutrient profiles are a major concern of dryland grain producers considering grazing sheep on cereal stubble fields. Our objective was to compare burned, grazed, tilled, trampled and clipped wheat stubble fields on changes in soil bulk density and soil nutrient profiles. Treatments were evaluated in a series of three experiments using a randomized complete block design and four replications at each site. Contrast statements were used to make pre-planned comparisons among treatments. For Experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined (Fall/Spr) grazed, and an untreated control. …

Incorporating Sheep Into Dryland Grain Production Systems Ii. Impact On Changes In Biomass And Weed Density, P. G. Hatfield, Andrew W. Lenssen, T. M. Spezzano, Sue L. Blodgett, H. B. Goosey, R. W. Kott, C. B. Marlow

Andrew W. Lenssen

Weed control in fallow management to conserve soil moisture and nutrients is the largest variable cost to dryland grain production. Our objective was to compare burning, grazing, tilling, trampling and clipping wheat stubble fields on changes in total above ground biomass and weed density. Treatments were evaluated in three experiments using a randomized complete block design for each experiment with four replications at each site. Contrasts statements were used to make pre-planned comparisons. For experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined (Fall/Spr) grazed, and an untreated control. For grazing treatments, five mature ewes …

Sheep Updates 2006 - Part 2, Darryl Smith, Kathryn Kemper, David Rutley, R. R. Woolaston, D. J. Brown, K. D. Atkins, A. E. Casey, A. J. Ball, David Hopkins, David Stanley, Leonie Martin, Arthur Gilmour, Remy Van De Ven, Geoff Duddy, Steve Semple, David Kessell, Andrew Thompson

Sheep Updates

This session covers six papers from different authors:

GENETICS

1. Novel selection traits - what are the possible side effects?, Darryl Smith, Kathryn Kemper, South Australian Research and Development Institute, David Rutley, University of Adelaide.

2. Genetic Changes in the Australian Merino since 1900, Sheep Genetics Australia Technical Committee, R.R. Woolaston Pullenvale, Queensland, D.J. Brown, Animal Genetics and Breeding Unit*, University of New England, K.D. Atkins, A.E. Casey, NSW Department of Primary Industries, A.J. Ball, Meat and Livestock Australia, University of New England

3. Influence of Sire Growth Estimated Breeding Value (EBV0 on Progeny Growth, David Hopkins, David Stanley, Leonie …

Crop Updates 2002 - Oilseeds, David Eksteen, K. Neil Harker, George W. Clayton, Keith Downey, Keith Alcock, Kevin Walden, Beven Addison, Peter Carlton, Kevin Morthorpe, Stephen Addenbrooke, Alex Ford, S. Hasan Zaheer, G. Walton, Imma Farré, Paul Carmody, J. A. Fortescue, D. W. Turner, B. Tan, Margaret C. Campbell, Ian Pritchard, Richard W. Bell, K. Frost, Mike Wong, Ross Brennan, Roger Jones, Jenny Hawkes, Debbie Thackray, Moin U. Salam, Ravjit K. Khangura, Art J. Diggle, Martin Barbetti, Phil Michael, Françoise Berlandier, Chriatiaan Valentine, Greg Shea, Glen Riethmuller, Rafiul Alam, Greg Hamilton, Jo Hawksley, Patrick Smith, Paul Neve, Felicity Flugge, Amir Abadi, Stephen Powles, Brett Glencross, John Curnow, Wayne Hawkins

Crop Updates

This session covers twenty seven papers from different authors:

1. Forward and acknowledgements, Dave Eksteen, ACTING MANAGER OILSEEDS PRODUCTIVITY AND INDUSTRY DEVELOPMENT Department of Agriculture

PLENARY SESSION

2. GMO canola - Track record in Canada, K. Neil Harker and George W. Clayton,Agriculture and Agri-Food Canada, Lacombe Research Centre, Lacombe, Alberta, R. Keith Downey, Agriculture and Agri-Food Canada, Saskatoon Research Centre, Saskatoon, Saskatchewan

3. GMO canola – Prospects in Western Australia farming systems, Keith Alcock, Crop Improvement Institute, Department of Agriculture

4. Diamondback moth (DBM) in canola, Kevin Walden, Department of Agriculture

CANOLA AGRONOMY

5. Getting the best out of …

Management Of Red Squirrel Feeding Damage To Lodgepole Pine By Stand Density Manipulation And Diversionary Food, Thomas P. Sullivan

Proceedings of the Eighteenth Vertebrate Pest Conference (1998)

The red squirrel (Tamiasciurus hudsonicus) feeds on the vascular tissues of sapling lodgepole pine (Pinus contorta) during spring periods in forests of interior British Columbia and Alberta, Canada. This damage may lead to mortality and reduced growth of crop trees in managed stands. Manipulation of stand density by pre-commercial thinning to densities < 1,000 stems/ha is an effective method to lower squirrel populations and feeding damage. Lowering stand density enhances the growth of crop trees, and understory herbs and shrubs as wildlife habitat, while protecting trees from squirrel feeding. This approach has been successful in several forest ecological zones. An alternative management tool is provision of diversionary food (sunflower seed) for those stands susceptible to feeding damage, and where stand thinning has already been completed. Diversionary food can be applied aerially and is very cost effective for protecting managed stands. These techniques may be used to maintain or even enhance species diversity of small mammal communities in those forest stands requiring protection.

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 and Staff 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 …

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 …

Phomopsis-Resistanct Lupins : Breakthrough Towards The Control Of Lupinosis, W A. Cowling, J. G. Allen, P Mcr. Wood, J. Hamblin

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

Attemots to control lupinosis in sheep have been thwarted by the unpredictable occurence of the disease in the field. The complex interaction of the toxin-producing fungus (Phomopsis leptostromiformis) with its host (the lupin plant), together with variable weather and paddock grazing conditions, have made it difficult to predict when stock are in danger of contracting the disease. The risk of lupinosis discourages many farmers from growing lupins, despite the many potential benefits of including them in crop rotations.

A team of Department of Agriculture plant breeders, plant pathologists, and animal scientists set out in the mid 1970s to find resistance …

Phomopsis Infection Of Lupin Seed, D S. Petterson, P. Mcr. Wood

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

Early reports of lupinosis in Western Australia implicated infected stems and leaves of the sandplain or W,A. blue lupin (Lupinus cosentinii) as the main source of toxicity.

After the introduction of low alkaloid varieties of L. augustifolius, lupinosis continued to oddur on stubbles but random testing of seeds showed only low levels of Phomopsis leptostromiformis infection.

However in 1976, scientists at the University of Western Australia who were evaluating the use of an all lupin seed ration for drought feeding sheep encounted lupinosis in one of their trials.Seven per cent of the seed used was found to be infected …

Cotton Fireweed : Potential Poison : Research Roundup, J Dickson, R. Hill

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

Although long known as a potential toxic species because of its content, and although it is widely distribuited in all Australian States, cotton fireweed has not generally been consdidered toxic because it is unpalatable and not usually eaten by stock.

In 1973 cattle deaths occured near Ravensthorpe which led to research into Senecio quadridentatus (cotton fireweed).

The plant must be seen as a potential toxic species in situations where the lack of other feed forces cattle to eat the normally unpalatable cotton fireweed.

Annual ('Wimmera') Ryegrass Toxicity, Geoffrey A. Pearce, O. M. Goss, P. H. Berry, J. L. Wise

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

Because annual ryegrass is one of the most widespread pasture plants in Western Australia, annual ryegrass toxicity is a threat to livestock in many agricultural areas—even though the area now affected is small.

The problem is being intensively studied by the Department of Agriculture and a working group has been set up to investigate potential control measures.

In this article the group reviews the problem and reports progress in its investigations to the end of 1973.

Wimmera Ryegrass Toxicity, Department Of Agriculture, Western Australia

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

Wimmera ryegrass toxicity has been reported for many years to affect sheep and occasionally cattle in New Zealand, South Australia and the United States of America.

In Western Australia, occasional reports since 1959 and severe outbreaks of staggers in the Katanning- Gnowangerup areas over the last two years prompted the investigation reported below.

Poison Sedge Can Kill Stock, M E. Nairn, T. E. H. Aplin, D. S. Petterson, A. J. Brighton

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

POISON SEDGE was first suspected of being toxic to livestock in Western Australia nearly 80 years ago.

Sudden deaths of sheep grazing areas on which poison sedge grew have been reported from many regions from Geraldton to Scott River.

This article reports a case of poisoning in the field, and the experimental reproduction of poison sedge toxicity in pen-fed sheep.

Superphosphate Deficiency Raises Pasture Oestrogens, H G. Neil, T. Marshall

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

A recent field experiment on established pastures at Esperance Downs Research Station has demonstrated a relationship between superphosphate application, pasture oestrogens and oestrogenic response in sheep.

Results of the experiment indicate that on phosphate deficient soils carrying oestrogenic clovers, the levels of oestrogenic materials in the pasture are increased if superphosphate applications are below those recommended for healthy pasture growth.

Deferred Grazing Improves Soft Spinifex Association, H Suijdendorp

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

THE Pastoral region in Western Australia where Triodia pungens (soft spinifex) makes up most of the vegetation, covers an area of about 17,000 square miles in the Forrest and De Grey pastoral areas.

On the deeper granitic sands in much of the region, plant associations revert to a pure stand of soft spinifex after about five or six years' grazing. It is common practice to burn at this stage, to encourage the re-establishment of other species and the production of palatable spinifex regrowth.

Phalaris Staggers : Prevention By Cobalt Bullets, Bryan J. Gorddard, P. P. Mann, A. J. Hadlow

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

FARMERS in the south west of Western Australia are familiar with the use of cobalt for the prevention of ill-thrift and deaths due to cobalt deficiency in sheep and cattle.

Less common is the use of cobalt for the prevention of chronic phalaris poisoning, known as phalaris staggers.

This condition is well known in eastern Australia, but only isolated cases have been recorded in W.A. no doubt due to the relatively small area sown to phalaris in this state.

Clover Disease Of Sheep In Western Australia, A B. Beck, M. R. Gardiner

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

DURING the past five years there has been a marked increase in the incidence of breeding abnormalities of sheep associated with the grazing of subterranean clover pastures.

This complex of diseases first became a major problem in Western Australia in the years following 1940 and eventually became known as "clover disease".

Chemical Poisoning In Animals. 3. Prussic Acid, H D. Seddon

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

HYDROCYANIC or prussic acid poisoning is a serious and not uncommon ailment of ruminants, and may be a cause of rapid death when pasture plants capable of developing dangerous levels of the poison are being grazed.

A Grazing Management Trial For The Control Of Lupinosis In Sheep, H G. Neil, C. M. Ralph, A. W. Hogstrom

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

A "WASTING" disease of sheep grazing on lupin stands, usually accompanied by heavy mortality, has become a serious problem in coastal areas between Perth and Geraldton in the past ten years.

Lupinosis, H W. Bennetts

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

LUPINOSIS is a disease which has caused severe mortalities in West Australian sheep flocks in recent years, and one which—because of the important role which lupins are playing in light land development—must inevitably continue to be a matter of serious concern.