Brief Summary of Minutes of Annual Meeting

The main item on the agenda was to discuss progress during the 2003 calendar year on the four current objectives of our multi-state project . The minutes may be reviewed through the following link: http://www.lgu.umd.edu/project/saes.cfm?trackID=2296

Objective 1:
Characterize the dynamics and impact of evolving insect pests and optimize insect management as an integral element of developing cropping systems.

GA: Pest arthropod populations were similar in conventional and Round-Up Ready systems of weed management. An early maturing variety of edible soybeans (Midori Giant) escaped damaging populations of stink bugs and caterpillars.
Soybean aphid (SBA) was detected in Georgia for the second year in a row.
Twenty-eight varieties of soybeans were screened for resistance to stink bugs and Lepidoptera pests. Varieties exhibited a large range of susceptibility to these pests. Fire ants in soybeans were controlled with Amdro and Lorsban; however, fewer spiders were collected in plots treated with these insecticides.
Warrior, Scout, Capture, Demon and Orthene were effective against soybean looper.

IN: A preliminary threshold of 250 SBA/plant up to R4 was established.
Planting date and plant age did not appear to have an impact on SBA density.
SBA outbreaks occurred 1-2 weeks after outbreaks in more northern states; thus, SBA moves from north to south. SBA overwintered in northern Indiana. Rhamnus cathartica, R. alnifolia, and R. lanceolata were shown to be overwintering hosts of SBA. Several species of Rhamnaceae supported fall migrants (gynoparae), but only R. cathartica and R. alnifolia supported the egg-laying generation (oviparae) of SBA. In the field, initial colonies of SBA are patchy and consist of nymphs. Eventually, SBA colonize entire fields and achieve a more uniform distribution. A model of SBA population dynamics is being developed.

KS: Resistance to SBA is being investigated using a visual rating scale using KS 4202 as the sentry variety. Antibiosis tests revealed three varieties with significantly reduced aphid reproduction. Dectes texanus has shifted from sunflowers to soybeans. D. texanus on both hosts are conspecific, but sunflower is a better host than soybean.

LA: Did not find SBA in 2003.

NE: SBA gradually spread throughout the eastern half of NE in 2003. Most damaging populations were found in northeastern NE. This colonization pattern was similar to 2002 but more fields were treated in 2003 than 2002. Milder temperatures in 2003 may have accounted for higher populations in 2003. Two out of four studies showed about a 10 bu/acre yield increase in SBA-treated plots compared to untreated plots. Soybean defoliation reduced early-season crop tolerance to weeds.

ND: SBA was found on buckthorn in the fall of 2003 at Moorhead, MN on the MN/ND border. SBA was found in highest abundance on late reproductive stage soybeans in 2003. SBA initially colonized the edge of soybean fields near shelterbelts; populations gradually became uniformly distributed in the field. Recommendation: scout field borders near shelterbelts first in early July to detect initial colonization by aphids. In a greenhouse test, MN0302 and Dynagro 3072 generated high populations of SBA but exhibited low damage. SBA became established on thiamethoxam-treated (applied to seed) plots 3 weeks later than on untreated plots. ND participated in the common experimental protocol for refining the SBA economic threshold. Karate Z was applied at R2, R3, R4 and R5. Aphid infestation was not high enough to obtain meaningful data.

OH: The threshold for SBA is 250-300/plant with increasing populations. In validation studies, in all cases where aphid populations midwest the threshold, yield losses occurred. Lorsban at 2 pt/acre gave excellent control of SBA; data suggest Lorsban has contact and fumigant action. CEAs and consultants reported yield increases of 5-15 bu/acre in fields treated for SBA. Proper management entails weekly sampling beginning at R2 and treating when populations reach 250-300 SBA/plant. In an insecticide screening trial, Furadan at 8 oz/acre and Lorsban at 24 oz/acre provided the best control of SBA.
In narrow row soybeans, skip row soybean planting is encouraged to avoid running over soybeans with spray equipment (treating for SBA). Heavy slug defoliation occurred soon after emergence when weather turned unseasonably cool. A $500,000 program funded by USDA-NCRS EQIP has been established and will make monies available to growers to sample and treat for slugs.

TN: Evaluated soybean cultivars for resistance to Dectes stem borer; for early MGV cultivars, Delta King was most damaged; least damaged was FFR. For late MGV cultivars, Dectes damage was less than for early MGV cultivars.
The pyrethroids, Asansa XL [0.05 lb (AI)/acre], Baythroid [0.03-0.044 lb (AI)/acre],Fury [0.05 lb (AI)/acre] and Karate Z [0.03 lb (AI)/acre] performed well against green stink bug. Lorsban [l lb (AI)/acre] was least effective.

TX: Populations of stink bugs were compared on MG IV, V, VI and VII soybeans planted in mid-April and late May. Basically, stink bugs, primarily southern green stink bug, built-up to damaging levels on MG IV soybeans planted early. However, for the late May planting date, stink bug populations did not exceed threshold levels on MG V and VI and VII soybeans. Planting MG V or VI soybeans in May/June may avoid damaging stink bug populations and allow early harvest before cool, wet weather occurs.

VA: SBA was found in soybean fields in 10 counties; however, populations did not approach damaging levels. Educational programs were conducted to alert clientele of this potentially devastating insect pest. Based on the Corn Earworm Advisory, corn earworm (CEW) problems on soybeans were predicted to be less in 2003 compared to 2002, and in fact, they were. About 60% of VA soybean acreage was treated for CEW in 2002; only 17% was treated in 2003. The % of soybean acres treated in August was well correlated with predictions based on a survey of field corn in July. Field-collected CEW moths from around the soybean-producing area of VA were subjected to varying rates of cypermethrin. No evidence of pyrethroid resistance was detected. However, field collected CEW moths reared from larvae collected around the soybean-producing area of VA did exhibit low levels of resistance. Growers were warned and encouraged to employ non-pyrethroid insecticides. Steward 1.25 SC at 4.6 and 6.7 oz/acre, Tracer 4SC at 2 oz/acre, Mustang Max at 2.8 and 4.0 oz/acre, Larvin at 10 oz/acre and Karate Z at 1.6 oz/acre provided at least 90% control of CEW.

WI: In field experiments, late-planted soybeans produced higher SBA populations than early planted soybeans. Results of experiments show that the economic threshold for SBA is 500/plant at R1. At R2/3, the threshold increases to 1000/plant. The best time to apply an insecticide for SBA is R/2. SBA was detected earlier on early- rather than late-planted soybeans. SBA tend to congregate in the uppermost nodes during June and early July after which their spatial distribution is less clumped. Adapted germplasm also was screened for SBA; populations ranged from 1000 to 2500 per plant which suggests that resistance to SBA can be incorporated into adapted germplasm.


Objective 2:
Define insect-vector ecology and virus-disease relationships and develop management strategies.

ND: Aphid-transmitted viruses were not detected in ND.

WI: Soybean dwarf virus was detected in soybeans in five counties in WI in 2003. Alfalfa mosaic virus (AMV) and soybean mosaic virus (SMV) were the most prevalent viruses infecting soybeans in 2003. Soybean germplasm was evaluated for reaction to AMV, SMV and bean pod mottle virus; differences among varieties for yield and grain quality were evident. This information was given to breeders for use in their programs.

Objective 3:
Biological control of the soybean aphid in North America.

IN: Harmonia axyridis is a common predator of SBA. Little parasitism occurs but fungal disease epidemics are common. Other predators are damselflies, flower flies and lacewing larvae. The major predator of SBA is Orius insidiosus. O. insidiosus populations were associated with thrips populations. Thrips may be sustaining O. insidious populations for later SBA predation. Hypothesis: O. insidiosus keep in check locally overwintering SBA but are unable to impact large migrant populations entering IN from the north.

KY: The predatory harvestman, Phalangium opilio, is a common predator of CEW eggs and also feeds on SBA. This predator only feeds at night. Also, CEW eggs are a better host diet than SBA. USDA/ARS Michigan: In cooperation with State Experiment Station scientists, the USDA PPQ Invasive Pests Management Laboratory in Niles, MI screened and evaluated exotic natural enemies of the SBA, modeled natural enemy impacts on SBA, conducted foreign exploration for SBA natural enemies and studied the interaction of predators and parasitoids on SBA biological control. Also, this facility reared the Wyoming strain of an established aphid parasitoid, Aphelinus albipodus (shipped 76,000 to MN and 447,000 to WI).

WI: In 2003, SBA was severe in southern WI. A. albipodus was released in 2002 and became established in 2003. Lady beetles are the most significant predator of SBA in WI. SBA natural enemy complex is diversifying following the recent introduction of this pest.


Objective 4:
Apply geospatial and precision technologies to advance pest management in soybeans.

LA: The drop cloth and light meter methods (measures light interception) of determining when to treat for defoliating insects gave similar results; both methods triggered an insecticide application within several days of one another.
Results confirm that light measurements using hand-held light meters can accurately predict when insecticide application is warranted. Use of vegetation indices generated by remote sensing correlated well to light interception and leaf area index (LAI) measurements. Thus, remote sensing shows promise as an accurate method of determining when to apply insecticide.

VA: Varieties and planting dates were manipulated to achieve various LAIs of field-grown soybeans. Infrared images of these plots were taken from a fixed-wing aircraft at three different altitudes. NDVI (normalized difference vegetation index) values were calculated from the infrared images. Results show a significant linear relationship between LAI and NDVI.

Georgia

Jones, D. C. and R. M. McPherson. 2003. Insect Management. Georgia Soybean Production Guide. CSS 03-02:58-66.

Seagraves, M. P. and R. M. McPherson. 2003. Residual susceptibility of the red imported fire ant (Hymenoptera: Formicidae) to four agricultural insecticides. J. Econ. Entomol. 96:645-648.

McPherson, R. M., W. C. Johnson, B. G. Mullinix, Jr., W. A. Mills, III, and F. S. Peebles. 2003. Influence of herbicide tolerant soybean production systems on insect pest populations and pest-induced crop injury. J. Econ. Entomol. 96:690-698.

McPherson, R. M., D. C. Jones, J. C. Garner, and G. K. Douce. 2003. Soybean insect pest alert: Soybean aphid now established in Georgia. Univ Georgia Coop. Ext. Serv. Misc. Publ. 105 (also @www.ces.uga.edu/pubcd/MP105.htm).

McPherson, R. M., M. L. Wells, W. A. Mills, III, and S. R. Jones. 2003. Control of velvetbean caterpillars on soybean, 2003. Arthropod Management Tests 28: F103.

McPherson, R. M. and W. A. Mills, III. 2003. Control of stink bugs on soybeans in Georgia, and impact on velvetbean caterpillar populations, 2002. Arthropod Management Tests 28: F104.

McPherson, R. M., J. D. Taylor and N. J. Roberson. 2003. Control of velvetbean caterpillars on soybean and impact on soybean loopers and threecornered alfalfa hoppers, 2002. Arthropod Management Tests 28: F105.

McPherson, R. M. and D. C. Jones. 2003. Soybean insects, pp. 37-38, in P. Guillebeau, N. Hinkle, and P. Roberts (eds.), Summary of losses from insect damage and costs of control in Georgia, 2001. Ga. Agric. Expt. Stn., Misc. Publ. 106.

Indiana

Voegtlin, D., R. J. O?Neil and W. Graves. 2004. Tests of suitability of overwintering hosts of Aphis glycines: identification of a new host association with Rhamnus alnifolia L?Hér. Annals Ent. Soc. Amer. (In press).

Ragsdale, D., R.J. O?Neil and D.. Voegtlin. 2004. Soybean aphid biology in North America. Annals Ent. Soc. Amer. (In press).

Rutledge, C. E., R., J. O?Neil, T. B. Fox and D. A. Landis. 2004. Soybean aphid predators and their use in IPM. Annals Ent. Soc. Amer. (In press).

Heimpel, G. E., D. W. Ragsdale, R. Venette, K. R. Hopper, R. J. O?Neil, C. Rutledge and Z. Wu. 2004. Prospects for importation biological control of the soybean aphid: anticipating potential costs and benefits. Annals Ent. Soc. Amer. (In press).

Wu, Z., K.R. Hopper, R. J. O?Neil, , D. Voegtlin, D. R. Prokrym, and G. E. Heimpel. Reproductive Compatibility and Genetic Variation between Two Strains of Aphelinus albipodus (Hymenoptera: Aphelinidae), a Parasitoid of the Soybean Aphid, Aphis glycines (Homoptera: Aphididae). Submitted to Biological Control.

Edwards, C. R., J. L. Obermeyer and L. W. Bledsoe. 2003. Soybean Insect Control Recommendations. Purdue University Cooperative Extension Service Publication E-77W. http://www.entm.purdue.edu/entomology ext/targets/e-series/EseriesPDF/E-77.htm. West Lafayette, IN. 7 pp.

Kentucky

Allard, C. M. 2003. Diel activity patterns and distribution of Phalangium opilio in soybean and the effect of diet on female reproduction. M.S. Thesis, University of Kentucky. 68 pp.

Louisiana

Baur, M.E., J. Ellis, K. Hutchinson, and D.J. Boethel. 2003. Contact toxicity of selective insecticides for non-target predaceous hemipterans in soybeans. J. Entomol. Sci. 38: 269-277.

Baur, M.E., and D.J. Boethel. 2003. Effect of Bt-cotton expressing Cry1Ac on the survival and fecundity of two hymenopteran parasitoids (Braconidae, Encyrtidae) in the laboratory. Biological Control 26: 325-332.

Baur, M.E., B.J. Fitzpatrick, and D.J. Boethel. 2003. Insect-resistant, transgenic soybeans: a new IPM tool. La. Agricult. 46 (4): 32-33

Baur, M.E., and D.J. Boethel. 2003. Tracking loopers with DNA. La. Agricult. 46 (4): 34.

Nebraska

Hunt, T. E., L.G. Higley, and F. J. Haile. 2003. Imported Longhorned Weevil (Coleoptera: Curculionidae) Injury to Soybean: Physiological Response and Injury Guild-Level Economic Injury Levels. J. Econ. Entomol. 96: 1168-1173.

Peterson, R.K.D., and T. E. Hunt, 2003. The Probabilistic Economic Injury Level: Incorporating Uncertainty Into Pest Management Decision-Making. J. Econ. Entomol. 96: 536-543.

Ziems, A., Giesler, L.J., and Hunt, T. 2003. Effect of foliar insecticide timing on incidence of bean pod mottle virus. Phytopathology 93:S95.

Echtenkamp, J., and T. E. Hunt. 2003. NK S24-K4 Control of bean leaf beetle on soybean, 2002. Arthropod Mgt. Tests. F95. Vol. 28.

Madsen, R. A. 2003. Host responses of soybeans and alfalfa to simulated insect defoliation and the development of economic injury levels. M.S. thesis, University of Nebraska, Lincoln.

Ohio

Gewal, S. K., P. S. Grewal, and R. B. Hammond. 2003. Susceptibility of North American native and non-native slugs (Mollusca: Gastropoda) to Phasmarhabditis hermaphrodita (Nematoda: Rhabditidae). Biocontrol Sci. Tech. 13:119-125.

Hammond, R. B. 2003. Gray garden slug control in field corn, 2002. Arthropod Management Tests. 28: F20.

Hammond, R. B. 2003. Seed treatments for control of insects in soybeans, 2002. Arthropod Management Tests. 28: F98.

Virginia

Malone, S., D. A. Herbert, Jr., and S. Pheasant. Determining adoption of integrated pest management practices by grains farmers in Virginia. J. of Extension (Accepted for publication, Jan. 2004).