Brief Summary of Minutes of Annual Meeting

NC-226 Meeting Minutes
Development of Pest Management Strategies for Forage Alfalfa Persistence
Embassy Suites
Lincoln, Nebraska
February 24-25, 2004
Tuesday, February 24


At 1:05 pm, Leon Higley commenced the meeting, with 10 in attendance (see separate list of attendees; Robin Groose and Fred Gray arrived within 30 minutes and Wayne Bailey arrived Wednesday morning). Leon apologized that because of urgent business, he would need to leave the meeting early that day, and part of the next morning. All members present introduced themselves.


At 1:10, Phil Larsen provided comments as the Administrative Advisor. Because our request last year for an extension of NC-226 was declined, he suggested that we request the formation of an NCT committee, to serve the function of exploration of a new committee with a different title and set of objectives. He stated that the procedure was relatively simple and that we had plenty of time. A letter should be written by at least two members of NC-226 with approval from two experiment stations to the North Central Research Association (NCRA). The request will be considered by the Multistate Committee, a subset of NCRA, who will then make a recommendation to NCRA at the July meeting asked, with a starting date of October 1 (just after the termination of NC-226). An NCT committee would last 1-2 years, and have three objectives: 1) study and recommend a new project (or not), 2) prepare justification and scope for a new project, and 3) prepare the multistate project outline. Ron Hammond asked if an NCR committee could be the recommendation. Phil answered that it could, and that an NCR would serve as an information exchange committee, perhaps to develop a specific publication. Bill Lamp asked if a list of participants for the NCT committee is needed. Phil answered that no, only 2 or more individuals with approval of two experiment stations. When asked about funding for travel to NCT meetings, Phil answered that usually funds are provided.


Phil added that changes in the naming of committees are being considered, including NCR to NCIEG (North Central Information Exchange Group) and NCT to NCDC (North Central Development Committee). Finally, Phil stated that as of July he will be going on phased retirement, and this would be the last meeting with this group.


At 1:35, Monte Johnson provided comments as the USDA Representative. This is Monte?s second year on NC-226. He provided and reviewed a packet of materials, including the National Animal and Plant Diagnostic Laboratory Networks, PSEP Newsletter, Land Grant Institutions, IPM Programs, and Budget Proposal. He specifically mentioned that invasive species is a grant opportunity, and there was discussion of the other IPM grant programs, including Crops At Risk (CAR) to help support the efforts of a new committee.


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Bill Lamp, as Secretary for the meeting, stated that reports and publication lists can still be submitted to him for inclusion in the NC-226 report. Send them to lamp@umd.edu.
Leon then initiated a discussion of possible directions for a new project. Dates were discussed for submission (see end of minutes for final decision). Each state stated how they feel about a new project.
Ohio (Ron Hammond and Lanny Rhodes) stated that forage work is decreasing, but the value of this project has been the multidisciplinary nature of the work. Collaborative research is therefore needed to address the problems on the 26 million acres of alfalfa being grown nationwide. Funding would be needed. Changes are underway at Universities away from forage research.
Wyoming (Fred Gray) agreed that money would be necessary for their participation, but pests are important in the persistence of forage stands.
Nebraska (Leon Higley and Tom Hunt) stated that applied answers to growers questions are needed in alfalfa pest management. However, Leon stated that his lab will be focusing on larger picture questions on insect feeding injury and plant physiology. Alfalfa would be a good system, in part, because of the multiple species of aphids that attack the crop. The theme of this work is stress physiology.
Phil, who had left to make a phone call, reported on specific procedures for submitting a new multistate proposal. (This information is reported at end of minutes as part of final discussions.)
Indiana (Jeff Volenec) plans to continue its forage work, including hardiness and survival, genetic and biochemical aspects of persistence, fertility effects, and functional genomics. Basically, Jeff reported a need to understand the forage plant.
Maryland (Bill Lamp) reported that his lab is going different directions, but would be interested in pursuing novel aspects of plant physiological, biochemical, and gene expression changes associated with potato leafhopper.
After a brief break, Jeff began reports from each state on research during 2003. Their comprehensive study of P and K management continues, finally resulting in the death of alfalfa plots that were planted in 1997. Persistence appears to need both P and K in balance, and applications of P alone caused death of plants. Mass per shoot appears to be best correlated with yield among the yield components, suggesting that rapid regrowth after harvest permits higher yields. Shoots per area became important as a factor only as of 2003. Plants are dying in summer, not winter, although the specific cause of death is elusive. Root constituent changes in part respond to K. He reported on some preliminary work on gene expression, suggesting that stressed plants have more variation in RNA.


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Bill Lamp then reported on two studies related to persistence of alfalfa and potato leafhopper injury. In the first, potato leafhopper injury during the establishment year after spring-seeding did not affect yield components on the first harvest of the second year. This suggests that leafhopper injury during establishment does not affect persistence. In the second study, yield components of resistant and susceptible cultivars are being compared. During the establishment year, no differences were detected in plant density, but during the summer of the second year, there was greater mortality of plants in the susceptible cultivar. This study is continuing during 2004.
The meeting was adjourned at 5:10 pm.
Wednesday, February 26
The meeting commenced at 8:05 am. Robin Groose gave a presentation on the genetic changes in alfalfa over time, especially with regard to brown root rot resistance. Using information from Russelle (2001), published in American Scientist, Robin described the historical sources of alfalfa germplasms. He provided data to suggest that alfalfa yields are increasing with time, although they appear more variable in recent years. He also cited Volenec et al. (2002) which showed no relationship between year of release and first harvest, however the relationship between year of release and fourth harvest has been increasing in recent years. He further suggested that the lack of response of yield to the development of multiple pest resistance germplasm could be from the ?Red Queen Hypothesis? (with regard to Alice running faster and faster just to stay in place). Based upon his and Fred Gray?s work with brown root rot, there is evidence of resistance in some old varieties such as Ranger and OK49, which have survived in abandoned plots since 1992. He created a new cultivar with resistance, using the set theory for cultivar synthesis.
Fred Gray then described the development of a protocol for screening brown root rot (BRR). Seeds are planted in the summer, inoculated in the fall, and evaluated in the spring. He used ATCC and #2 as standard isolates for comparison to new germplasms. He added that the survey of BRR now can be done by soil testing.
Leon Higley then described research in his lab on aphid systems of injury. He suggests that there is a common mechanism of injury in spite of varying toxins, etc., that is associated with the blocking of starch loading in the mesophyll. If this mechanism is found to be true, then each aphid species is not unique in their injury, and screening for resistance should not be on the basis of mesophyll structure and function. Rather, the impact of injury on primary metabolism and synthesis should be determined. Furthermore, time course studies should be started soon after injury because of rapidly cascading effects.
Lanny Rhodes then introduced a discussion of the ?Decades Trial?, involving a number of states and the selection of old and new varieties for concurrent comparisons. He and Jennifer Ariss are especially interested in comparing disease resistance. Jennifer then continued by describing her research, which overall seems to suggest that the


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modern varieties had less disease (e.g., anthracnose, fusarium wilt) than older varieties, although some older varieties (e.g. Ranger) do show resistance. In addition, the more recent releases generally show greater ground cover as of fall 2003, more total yield from 99-03, and fewer diseased stems based on number per plot. She is now testing disease resistance versus persistence by selection. She cross-pollinated six varieties to produce new clones, and these clones will be tested against standard protocols.
Jeff Volenec asked how they might explain the performance of the old variety, Vernal, which fell in the middle of the set of those tested in spite of low ratings for disease resistance. He asked if there has been actual improvement, and suggested that rather than selecting for multiple disease resistance, there should be selection for yield and persistence.
Wayne Bailey described two studies in progress at Missouri. One is being conducted with Jerry Nelson on leafhopper tolerance and alfalfa persistence as affected by potassium fertility. He said they have found no yield drag associated with the new glandular-haired varieties. Potassium effects are starting now in year two of the study. The second study with Dr. Blevins is investigating the relationship between boron fertility and alfalfa persistence.
A
t 10:05, a brief break was taken.
The remainder of the morning was devoted to discussion of a future project. Bill Lamp started by displaying key words/phrases, then adding as the discussion continued:
I. Cropping Systems
a. Alfalfa
b. Forage legumes (This was decided as our focus.)
c. Other legumes
d. Forages ? grasses, legumes
e. Dairy industry
II. Changing Agronomic Practices and Environments
a. Organic production
b. Round-up Ready cultivars
c. Nontarget organisms
d. Fertility effects
e. Pesticides
f. Irrigation
g. Rotation

III. Topics related to persistence
a. Plant death
b. Stand persistence
c. Root constituents
d. Protein dynamics
e. Gene expression
f. Root-shoot interactions
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g. Pest interactions

IV. Issues
a. Molecular and physiological changes
b. Functional genomics
c. Global warming and changing pest complex
d. Invasive plant and insect pest species
e. Nitrogen fixation
f. Complex interactions
g. Abiotic and biotic stresses/tolerance
h. Mechanisms
i. Functional biology
j. Sustainability
V. Project features
a. Multidisciplinary
b. Private industry involvement
c. Both basic and applied foci
d. Standard protocol across states (not needed)
e. Standardized plant testing
f. Shared collaboration on specific research
g. Funding, e.g. SARE, Organic Transition
h. National in scope (not just NC region)
i. Application of new skills and tools

We developed a tentative title for the new project of, ?Impact of Changing Practices on Stress Tolerance within Forage Legumes.? As determined before, Jeff Volenec will host the next meeting in Indianapolis in February 2005. The dates for project development are as follows:


1. July, 2004: Request NCT committee formation to last from Oct. 1, 2004 to Sept. 30, 2006 from NCRA.
2. Fall, 2004: Prepare proposal to fund workshop to develop details of issues, to be held October, 2005.
3. February, 2005: Initial NCT meeting to finalize title and objectives, scope, justification, and general methods; plans for workshop (if funded).
4. October, 2005: Hold workshop, if funded.
5. December, 2005: Submit proposal to NCRA, to be reviewed by NCA committee during January, 2006.
6. March, 2006: Proposal reviewed by NCRA.
7. October, 2006: Start of new multistate project.
Leon Higley concluded the meeting at 11:30. The group thanked Leon for his hospitality. Also, they thanked Phil Larsen for his contributions to the project.
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Accomplishments and Impacts:

Objective 1. To Elucidate Mechanisms By Which Biotic Agents Interact With Abiotic Factors to Limit Stand Persistence of Forage Alfalfa

Results from Ohio and Indiana continue to indicate that death of alfalfa plants is primarily occurring during the growing season instead of over winter. This is in sharp contrast to the generally accepted belief that winter killing is the primary reason alfalfa stands decline over time. Large variation in plant size exists between seeding date and fertility treatments, and this results in the few large plants present in plot contributing disproportionately to total forage yield. Missouri data indicate that plant losses in summer are exacerbated by potato leafhopper infestation irrespective of potassium (K) fertilizer application. Application of phosphate (P) without K fertilizer resulted in complete stand losses in Indiana. Starch, protein and amino acid concentrations are lower in roots of plants grown in high-P soils without K fertilizer. Low levels of these root reserves may be contributing to poor alfalfa persistence. Wyoming data indicates that brown rot fungi (Phoma sclerotioides ) contribute to stand decline, and that winter stress is a necessary component of disease development.

Objective 2. To Enhance Alfalfa Persistence Through Improved Plant Resistance to Key Pests by Conventional Breeding and Genetic Engineering Approaches

A total of five states reported on studies examining the potential of plant resistance to key pests in alfalfa. Maryland conducted studies to test for effects of leafhopper injury on alfalfa establishment. Experiments were established in two fields. Results indicated no significant effect of injury on the yield components of alfalfa cultivars, suggesting that alfalfa is tolerant of long-term leafhopper injury during the establishment year, with no long-term effects on persistence in subsequent years. The second year of a field study quantified and compared the yield components of a locally adapted, susceptible alfalfa cultivar and a leafhopper resistant cultivar. Results indicate a declining plant density especially in the susceptible cultivar during 2003 in comparison to the susceptible cultivar.
Michigan is conducting studies to evaluate new commercial resistant varieties for PLH damage (hopper burn) and alfalfa yield. In the trial planted in 2000 all resistant varieties were not significantly different in yield or hopper burn from the non-resistant varieties for cut 2 but were significantly lower in hopper burn than the non resistant varieties in cut 3. Resistant varieties were significantly higher yielding and lower in hopper burn than non-resistant varieties in the trial established in 2001
Minnesota conducted studies to assess the potential for tolerance or resistance among alfalfa cultivars to the alfalfa leafminer. They found no significant differences in leaf mining damage to trifoliolates among the 86 entries, or among glandular-haired and traditional commercial varieties. The low levels of resistance to A. frontella among glandular-haired commercial alfalfa varieties and numerous experimental entries of M. sativa germplasm, confirms the need for alternative A. frontella management strategies such as biological control and possible manipulation of harvest schedules.
Ohio continued field plot trials in 2003 in west-central Ohio to evaluate yield and persistence of glandular-haired alfalfa varieties with resistance to potato leafhopper. Across trials under heavy PLH pressure, insecticide treatment was economically justified for the susceptible cultivar in 11 of the 14 summer harvests but in only 6 of the 14 harvests for the resistant cultivar. These results demonstrate the improvement in PLH-resistance with recently developed glandular-haired cultivars.
Virginia conducted a study to compare pest densities of alfalfa weevil and potato leafhopper in treated and untreated glandular-haired and non-glandular haired alfalfa. Differences in yields and forage quality between varieties were rarely significant and often inconsistent. Based on our study, we recommend that growers considering investing in glandular-haired alfalfa should wait until seed companies substantially improve the level of PLH resistance in these varieties, which will probably be achieved within a few years, as ?third-generation? varieties are commercially available now.
Wyoming reported on resistance for plant diseases. They continue towards the development of a brown root rot resistant variety, as well as, a standard protocol for alfalfa breeders for use in evaluating alfalfa lines for reaction to this root rot pathogen. The standard protocol for brown root rot for the North American Alfalfa Improvement Conference publication, ?Standard Tests to Characterize Alfalfa Cultivars," is nearing completion. Progress is being made in the field evaluation of the brown root rot resistant cultivar developed in Wyoming.

Objective 3. To Identify and Enhance Biological and Cultural Control Measures that Reduce Pest Populations and Improve Forage Alfalfa Persistence

Illinois provided the only report for this objective. A survey of the alfalfa blotch leafminer and its natural enemies was completed. They concluded that the leafminer is not a serious threat to alfalfa production at this time although its major parasitoids were not detected.

Objective 4. To Integrate Control Measures with Decision-Making Guidelines
for Adoption by Specific States/Regions

Publications:

Illinois

Lundgren, J. G., K. L. Steffey and R. N. Wiedenmann. 2004. The distribution and prevalence of the alfalfa blotch leafminer (Diptera: Agromyzidae) in Illinois. Great Lakes Entomologist, in press.

Indiana

Haagenson D.M., S.M. Cunningham, B.C. Joern and J.J. Volenec. 2003. Autumn defoliation effects on alfalfa winter survival, root physiology, and gene expression. Crop Sci. 43:1340-1348.

Cunningham S.M., P. Nadeau, Y. Castonguay, S. Leberge and J.J. Volenec. 2003. Raffinose and stachyose accumulation, galactinol synthase expression, and winter injury of contrasting Medicago sativa germplasms. Crop Sci. 43:562-570.

Haagenson D.M., S.M. Cunningham and J.J. Volenec. 2003. Root physiology of less fall dormant, winter hardy alfalfa selections. Crop Sci. 43:1441-1447.

Kalengamaliro N.E., S.M. Cunningham and J.J. Volenec. 2003. Growth, sugar accumulation, and dark respiration of suspension cell cultures derived from contrasting alfalfa cultivars. Plant Cell Tiss. Organ Cult. 72:163-171.

Meuriot, F., J.-C. Avice, M.-L. Decau, J.-C. Simon, P. Laine, J.J. Volenec, and A. Ourry. 2003. Accumulation of N reserves and vegetative storage protein (VSP) in taproots of non-nodulated alfalfa (Medicago sativa L.) are affected by mineral N availability. Plant Sci. 165:709-718.

Meuriot, F., C. Noquet, J.-C. Avice, J.J. Volenec, S.M. Cunningham, T.G. Sors, S. Caillot, and A. Ourry. 2003. MeJA reduces N uptake, changes N partitioning, stimulates VSP storage in taproots of Medicago sativa L. and induces expression of a 32 kDa genes, a VSP with chitinase activity. Physiol. Plantarum 120:113-123.

Noquet, C., F. Meuriot, J.-C. Avice, A. Ourry, S.M. Cunningham, and J.J. Volenec. 2003. Short-day photoperiod induced changes in N uptake, N partitioning and accumulation of vegetative storage proteins in two Medicago sativa L. cultivars. Func. Plant Biol. 30:853-8.

Berg, W.K., S.M. Cunningham, S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. Phosphorus and potassium effects on alfalfa yield components, physiology, and stress tolerance. Amer. Soc. Agron. Meeting, Denver, CO.

Berg W.K., S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. Enhancing alfalfa production through improved potassium management. Better Crops. 87:8-11.

Berg W.K., S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. Improved phosphorus management enhances alfalfa production. Better Crops. 87:20-23.

Berg, W.K., S.M. Cunningham, S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. The impact of phosphorus and potassium nutrition on alfalfa root carbon and nitrogen pools following defoliation. Agron. Abstr.: C02-berg700438-poster.

Berg, W.K., S.M. Cunningham, S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. Phosphorus and potassium effects on alfalfa yield components, physiology, and stress tolerance. Agron. Abstr.: A09-berg559158-oral.

Howard, S.M., W.K. Berg, S.M. Cunningham, S.M. Brouder, B.C. Joern, K.D. Johnson, and J.J. Volenec. 2003. Phosphorus and potassium fertilizer effects on soil nutrient concentration, and their impact on alfalfa yield components. Agron. Abstr.: S04-howard133968-poster.

Al-Hadid, K., S.M. Cunningham, and J.J. Volenec. 2003. Characterization of defoliation-responsive genes in Medicago sativa. Agron. Abstr.: C02-al-hadid977857-poster.

Milton, A., T. Henderson, S.M. Cunningham, J.J. Volenec, and J.A. Gana. 2003. Allele structure of the ROOTCAR1 locus in populations of diploid and tetraploid alfalfa (Medicago sativa L.). Annu. Meeting of the Amer. Soc. Plant Biol. Honolulu, HI., Abstr. No. 211.

Cunningham, S.M., W.K. Berg, S.M. Brouder, B.C. Joern, K.D. Johnson, K. Dalton and J.J. Volenec. 2003. Phosphorus and potassium effects on alfalfa (Medicago sativa L.) root physiology during post-defoliation shoot regrowth. Annu. Meeting Amer. Soc. Plant Biol. Honolulu, HI., Abstr. No. 433.

Volenec, J.J., S.F. Abu Qamar, and S.M. Cunningham. 2003. Phosphate nutrition effects on growth, phosphate transporter expression, and physiology of alfalfa (Medicago sativa L.). Annu. Meeting Amer. Soc. Plant Biol. Honolulu, HI., Abstr. No. 434.

Maryland

Lamp, W.O. 2003. Persistence of Alfalfa as Impacted by Insect Pests. University of Maryland Integrated Pest Management 2002 Progress Report.

Lamp, W., J.J. Volenec, W.K. Berg, A.L. Barta, R.B. Hammond, L.H. Rhodes, R.M. Sulc, J. Ariss, R. Leep, P. Vincelli, T. Denlinger, C. Laub, and R. Youngman. 2003. Development of pest management strategies for forage alfalfa persistence. Proceedings of the Fourth National Integrated Pest Management Symposium. Indianapolis, IN. April 8-10, 2003.

Michigan

Leep, R., Dietz, T., and Min, D. 2003. Alfalfa Variety Trial Results. http://www.msue.msu.edu/fis/

Lamp, W., Volenc, J., Berg, W. K., Barta, A. L., Hammond, R. B., Rhodes, L. H., Sulc, R. M., Ariss, J., Leep, R., Vincelli, P., Denlinger, T., Laub, C., and Youngman, R. 2003. Development of Pest Management Strategies for Forage Alfalfa Persistence. Proceedings of the Fourth National Integrated Pest Management Symposium. Indianapolis, IN. April 8-10, 2003.

Caddel, J., Undersander, D., Anderson, B., Brummer, E. C., Hansen, J., Joos, D., Johnson, K., Kallenbach, R., Leep, R., Meyer, D., Owens, V., Roozeman, K., Sheaffer, C., Spitalieri, R., Sulc, R. M., and Todd, R. 2003. Reporting CAIC Variety Tests in Crop Management on the Web. Proceedings of Central Alfalfa Improvement Virtual Conf. 21-22 July 2003.

Minnesota

Heimpel, G.E. & F. Meloche. 2001. Biological control of alfalfa blotch leafminer (Diptera: Agromyzidae) in Ontario: status and ecology of parasitoids 20 years after introduction (Hymenoptera: Braconidae and Eulophidae). Great Lakes Entomol. 34: 17-26. (published in 2003).

R.C. Venette, W. D. Hutchison, E.C. Burkness and C.C. Sheaffer. Evaluation of experimental and glandular-haired alfalfa cultivars for tolerance to alfalfa blotch leafminer (Diptera: Agromyzidae) in Minnesota. Great Lakes Entomol. (submitted, 12/03).

Hutchison, W.D., E. Cullen. 2003. Cowpea Aphids on Alfalfa in Wisconsin and
Minnesota. MN Vegetable IPM Newsletter. VegEdge: 5(6): 2 pp. On-line:
http://www.vegedge.umn.edu/mnvegnew/vol5/808cow.htm

Hutchison, W.D., E. Burkness, R. Koch, S. Wold, K. Bennett. 2003. Spring
Insect Updates -Potato Leafhopper. MN Vegetable IPM Newsletter. VegEdge:
5(1): 2 pp.; http://www.vegedge.umn.edu/mnvegnew/vol5/526mag.htm

Nebraska

Madsen, R. A., T. E. Hunt, and L. G. Higley. 2004. Simulated clover leaf weevil injury and alfalfa yield and quality. Agron. J. 96: 224-228.

Ohio

Sulc, R.M., R.B. Hammond, L.H. Rhodes, and H. Willson. 2003. Glandular-haired alfalfa: a new integrated pest management tool. p. 22-23. In NC IPM for our environment, for our future, NC Region IPM Grants Program 1998-2000.

Sulc, R.M., J.S. McCormick, L.H. Rhodes, D.J. Barker, and R.B. Hammond. 2003. Ohio forage performance trials, 2003. Horticulture and Crop Science Series 195. Ohio State Univ. Available at http://www.ag.ohio-state.edu/~perf/.

Sulc, R.M., K.D. Johnson, C.C. Sheaffer, D.J. Undersander, and E.V. Santen. 2004. Forage quality of potato leafhopper resistant and susceptible alfalfa cultivars. Agron. J. (in press).

Lamb, J.S., C.C. Sheaffer, E.C. Brummer, L.H. Rhodes, R.M. Sulc, and D.J. Undersander. 2003. Comparing forage yield and quality of alfalfa cultivars released from the 1940‘‘s through the 1990‘‘s. Abstract no. C06-lamb771003-oral, Agronomy Abstracts. [CD-ROM computer file]. ASA, Madison, WI.

Lamp, W., J.J. Volenec, W.K. Berg, A.L. Barta, R.B. Hammond, L.H. Rhodes, R.M. Sulc, J. Ariss, R. Leep, P. Vincelli, T. Denlinger, C. Laub, and R. Youngman. 2003. Development of pest management strategies for forage alfalfa persistence. Proceedings of the Fourth National Integrated Pest Management Symposium. Indianapolis, IN. April 8-10, 2003.

Caddel, J., D. Undersander, B. Anderson, E.C. Brummer, J. Hansen, D. Joos, K.D. Johnson, R. Kallenbach, R. Leep, D. Meyer, V. Owens, K. Roozeman, C.C. Sheaffer, R. Spitalieri, R.M. Sulc, and R. Todd. 2003. Reporting CAIC Variety Tests in Crop Management on the Web. Proceedings of Central Alfalfa Improvement Virtual Conf. 21-22 July 2003.

Sulc, R.M., E. Santen, K.D. Johnson, C.C. Sheaffer, and D. Undersander. 2003. Forage quality of glandular-haired and standard alfalfa cultivars. p. 1 In Forage Progress Vol. 1, April 2003. American Forage & Grassland Council, Geogetown, TX. Available online at http://www.afgc.org/afgcforageprogressapril2003.pdf.

Ariss, J., L.H. Rhodes, R.B. Hammond, and R.M. Sulc. 2003. Influence of potato leafhopper injury on Fusarium crown rot development in three alfalfa varieties. Am. Path. Soc. Meeting. August 9-13. Charlotte, NC.

South Dakota

No publications reported.

Virginia

Dellinger, T. A. 2003. Combined roles of glandular-haired alfalfa and natural enemies in alfalfa pest management in Virginia. Ph.D. Dissertation, Virginia Tech, Blacksburg, VA.

Dellinger, T. A., R. R. Youngman, and C. A. Laub. 2003. Recovery of Oomyzus incertus (Hymenoptera: Eulophidae), a larval parasitoid of Hypera postica (Coleoptera: Curculionidae), in Virginia. J. Entomol. Sci. 38: 141-142.

Wisconsin

Grau, C.R. 2004. Influence of alfalfa brown root rot on winterkill. Proceedings of the 2004 Wisconsin Fertilizer, Aglime, and Pest Management Conference 43:270-274.

Wyoming

Gray, F.A. and D.W. Koch. 2004. Alfalfa disease management. University of Wyoming, College of Agriculture, Cooperative Extension Service publication, B-1136, 35pp. (on-line at www.uwyo.edu/ces/plantsci.htm, in press).

Gray, F.A., C.R. Hollingsworth, C.J. Reedy, L.B. Powers, D.E. Legg, and R.W. Groose. 2004. Pathogenicity of 14 isolates of Phoma sclerotioides pathogenic to alfalfa. Phytopath. Abstr. (in press).

Hollingsworth, C.R., F.A. Gray, and D.W. Koch. 2003. Distribution and incidence of brown root rot of alfalfa in Wyoming, U.S.A. Can. J. Plant Path. 25:215-217.

Hollingsworth, C.R., R.W. Groose, and F.A. Gray. 2003. Comparative disease reactions of cycle 0 and cycle 1 alfalfa following inoculation with Phoma sclerotioides. Phytopath. 93:S36.