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Barley yellow dwarf is recognized as an important disease problem in winter wheat production in the southeastern United States, but there is relatively little known about the ecology and epidemiology of barley yellow dwarf virus (BYDV) in this region. From 1991 to 1993, and in 1996 and 1997, winter wheat was sampled for BYDV throughout the principal wheat production areas in South Carolina. In addition, in 1997, a small number of samples were collected from fields in North Carolina and Kentucky. Plant samples were assayed to determine the BYDV serotype and, subsequently, coat protein sequences of isolates within the same serotype were compared using restriction fragment length polymorphisms. Representative BYDV isolates from South Carolina and type isolates from New York were compared in aphid transmission experiments using aphid species collected from South Carolina and laboratory colonies maintained in New York. The predominant BYDV serotype in South Carolina (in all years) was PAV, accounting for 94% of the total BYDV-infected samples analyzed. The RPV serotypes were more abundant in samples collected from western North Carolina and Kentucky. PAV isolates from all regions were identical to the New York BYDV-PAV in terms of serology and restriction fragment patterns. Furthermore, the aphid transmission phenotypes were similar for South Carolina and New York BYDV isolates. The predominant aphids colonizing winter wheat in South Carolina included Schizaphis graminum, Rhopalosiphum rufiabdominalis, R. padi, and Sitobion avenea. The South Carolina clones of R. padi and S. avenae were similar to the New York laboratory clones in their abilities to transmit various BYDV isolates from New York and South Carolina. In contrast to the New York clone of Schizaphis graminum that can vector SGV, PAV, and RPV, the S. graminum clone from South Carolina was not a vector of any BYDV serotype tested. R. rufiabdominalis was found to be an efficient vector of PAV, RPV, and RMV isolates, but did not transmit MAV or SGV.

The male, female, and larva of Micrasema florida, n. sp. (Trichoptera: Brachycentridae), is described from Coastal Plain streams of Alabama and the western Florida panhandle. The species belongs in the Micrasema rusticum Group and closely resembles Micrasema ozarkana Ross and Unzicker, 1965. The male lacks thick, sclerotized straps on abdominal segment IX. The female has anterior emarginations on the abdominal terga. The larva has a pale yellow head with light brown muscle scars and builds a case that is abruptly narrowed posteriorly.

‘Bailey’ (Reg. No. CV-111, PI 659502) is a large-seeded virginia-type peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) with partial resistance to fi ve diseases that occur commonly in the Virginia-Carolina production area: early leaf spot (caused by Cercospora arachidicola Hori), late leaf spot [caused by Cercosporidium personatum (Berk. & M.A. Curtis) Deighton], Cylindrocladium black rot [caused by Cylindrocladium parasiticum Crous, M.J. Wingf. & Alfenas], Sclerotinia blight ( caused by Sclerotinia minor Jagger), and tomato spotted wilt (caused by Tomato spotted wilt tospovirus). It also has partial resistance to southern stem rot (caused by Sclerotium rolfsii Sacc.). Bailey was developed as part of a program of selection for multiple-disease resistance funded by growers, seedsmen, shellers, and processors. Bailey was tested under the experimental designation N03081T and was released by the North Carolina Agricultural Research Service (NCARS) in 2008. Bailey was tested by the NCARS, the Virginia Agricultural Experimental Station, and fi ve other state agricultural experiment stations and the USDA-ARS units participating in the Uniform Peanut Performance Tests. Bailey has an alternate branching pattern, an intermediate runner growth habit, medium green foliage, and high contents of fancy pods and medium virginia-type seeds. It has approximately 34% jumbo and 46% fancy pods, seeds with tan testas and an average weight of 823 mg seed −1 , and an extra large kernel content of approximately 42%. Bailey is named in honor of the late Dr. Jack E. Bailey, formerly the peanut breeding project’s collaborating plant pathologist.

Susceptibility to viral and fungal diseases is a major factor limiting profit in the production of virginia-type peanuts (Arachis hypogaea L.) in the South Carolina coastal plain. Field tests were conducted over a three-year period (2006–08) to evaluate the disease resistance of 47 experimental virginia-type breeding lines and eight cultivars. Relative to commercially available standards, cultivar Bailey (recently released by N. C. State Univ.), three sister lines (N03088T, N03089T, and N03090T), and N03091T were found to have consistently less susceptibility to tomato spotted wilt tospovirus; late leaf spot, Cercosporidium personatum (Berk. and Curt.) Deighton; and stem rot, Sclerotium rolfsii Sacc. The level of field resistance measured for these three diseases was comparable to that of a resistant runner-type cultivar, Georgia-03L. Yield was highly correlated with multiple disease resistance, and yield performance of some resistant lines exceeded the best commercial standard cultivars under reduced fungicide programs. Potential negative attributes of Bailey, its sister lines, and N03091T were a greater susceptibility to leafhopper injury, Empoasca fabae (Harris), and a relatively larger plant size at maturity, without well defined rows to facilitate digging. Other lines that demonstrated reduced susceptibility to both tomato spotted wilt and stem rot were N03005J and N02009. Although only evaluated in the last test year, five Univ. of Florida lines (FLMR7, FLMR9, FLMR12, FLMR14, and FLMR15) and Georgia-08V (recently released by the Univ. of Georgia) also showed some reduction in stem rot susceptibility relative to the standard (cultivar NC-V 11). Equally important, many experimental lines were identified with significantly greater disease susceptibility than current commercial cultivars. Under South Carolina production conditions, these lines would be poor candidates for advancement. Deployment of the multiple disease resistance found in these experimental cultivars offers several potential benefits beyond direct yield improvement: reduction of fungicide input costs for both foliar and soil disease control, prolonging the utility of currently available fungicides, and reduction of weather related harvest risk by allowing earlier initial planting dates.

A burrower bug, Pangaeus bilineatus (Say) (Heteroptera: Cydnidae), is known to feed extensively on peanut, Arachis hypogaea L., pods; particularly under certain reduced tillage production conditions. These bugs produce a strong odor when infested peanuts are uprooted, and previous anecdotal evidence indicated that burrower bug feeding is detrimental to peanut flavor. Various levels of burrower bug kernel feeding (0, 5, 10, 25, and 50% of seed by weight) were evaluated for effects on peanut flavor and oil quality. Burrower bug feeding had no detrimental effect on flavor as determined by trained panelists using descriptive sensory analysis. There was a slight, but measurable effect on oil quality as determined by a decrease in oxidative stability and an increase in peroxide values with increased levels of feeding. There was no measurable effect on free fatty acid content or fatty acid profile at the feeding levels tested. The data indicate that incidental feeding (

There are anecdotal claims that some fungicides cause physiological peg strength enhancement beyond mere suppression of the diseases, which can reduce peanut peg strength. We tested eleven...

Aflatoxin contamination of peanut kernels, Arachis hypogaea L., was associated with feeding by a burrower bug, Pangaeus bilineatus (Say). Kernel samples were divided into three grade categories: total sound mature kernels (TSMK), other kernels (OK), and damaged kernels (DK); and each of these grade categories was subdivided based on evidence of burrower bug feeding. Within TSMK, 100% of detectable aflatoxin contamination was associated with burrower bug kernel feeding, and kernels with feeding sites had a significantly higher concentration of aflatoxin than kernels without feeding sites (7.5 vs 0.0 ppb). Within the OK grade category, differences in aflatoxin contamination were not significant due to the inability to conclusively examine these kernels for feeding sites. Within the DK grade category, aflatoxin concentration was significantly higher in kernels with feeding sites than in kernels without observable feeding sites (286.5 vs 0.4 ppb), and 99.9% of contamination was associated with burrower bug feeding. Across all grade categories, aflatoxin levels were 65X higher in kernels with observable burrower bug feeding, and 98% of all aflatoxin contamination was associated with burrower bug feeding. The DK grade category had the highest concentration of aflatoxin and accounted for 45% of total contamination. Burrower bug-induced aflatoxin contamination of the TSMK grade category is particularly significant because this source would be most difficult to remove from the food supply. Contamination of the DK category is also economically significant because this grade component is specifically examined for Aspergillus at the buying point, and growers are severely penalized for detection.

A 2-yr study was conducted on the effects of tillage and soil insecticide (chlorpyrifos) treatment on peanut arthropod pests. A 3 by 2 split-plot experiment with five replications was subjected to factorial ANOVA. Main plot treatments consisted of three tillage systems: conventional moldboard plow, strip tillage into a killed wheat cover crop, and strip tillage into corn stubble residue. Subplot insecticide treatments were granular chlorpyrifos applied at early pegging (growth stage R2) and untreated. Populations of corn earworn, Helicoverpa zea (Boddie), and velevetbean caterpillar, Anticarsia gemmatalis Hübner, were lower in strip tillage systems. Chlorpyrifos applications caused corn earworm outbreaks in all tillage systems, but these applications were more disruptive in strip tillage. Chlorpyrifos treatment also increased populations of fall armyworm, Spodoptera frugiperda (J.E. Smith), but had no measurable effect on velvetbean caterpillar populations. Pod damage from lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), and wire-worms, Conoderus spp., was lower in strip tillage systems, and chlorpyrifos suppressed pod damage in all systems. Threecornered alfalfa hopper, Spissistilus festinus (Say), damage to peanut was greater in the wheat residue strip tillage system. Chlorpyrifos treatment reduced threecornered alfalfa hopper damage in all systems. Spider mite injury was not affected by tillage, but chlorpyrifos treatments resulted in mite outbreaks in all tillage systems. Burrower bug, Pangaeus bilineatus Say, injury to peanut kernels was greater in the strip tillage systems in 1999; and burrower bug injury was suppressed in the strip tillage systems by chlorpyrifos treatment. There was a significant interaction effect for burrower bug injury between tillage and insecticide treatment. Incidence of tomato spotted wilt virus also was reduced by strip tillage. Use of an effective fungicide program and a 3-yr crop rotation out of peanut production probably obscured any potential tillage effects on fungal diseases (southern stem rot, Rhizoctonia limb rot, and leaf spot). However, chlorpyrifos treatment increased Rhizoctonia limb rot incidence. Weed populations were generally greater in strip tillage systems, but postemergence herbicides effectively eliminated any potential confounding effect on yield and grade. Yield was not affected by tillage in either year, and chlorpyrifos had no effect on yield in 1998. In 1999, however, chlorpyrifos increased yield in both strip tillage systems. Neither tillage nor insecticide treatment affected grade (percentage total mature kernels) in 1998, but in 1999 grade was highest in conventional tillage and grade was improved by chlorpyrifos treatment in strip tillage systems. Crop value losses of $249 and $388/ha were attributed to burrower bug injury in untreated corn and wheat residue strip tillage systems, respectively. This injury may have been an anomaly of drought conditions but, given the potential economic impact, burrower bug merits further study in conservation tillage peanut production.

The benefits of chlorpyrifos (Lorsban 15G) soil insecticide treatment in standard (chlorothalonil) and developmental (tebuconazole) peanut fungicide programs were compared in five field tests over a 3-yr period. Chlorpyrifos treatment reduced incidence of southern stem rot (Sclerotium rolfsii) and insect pod injury, while increasing yield in the standard fungicide program. In contrast, chlorpyrifos treatment did not measurably affect stem rot incidence or yield in the tebuconazole program, and insect pod injury was reduced in only one of three years. Tebuconazole reduced Rhizoctonia limb rot (R. solani AG-4) and stem rot incidence, and decreased pod injury relative to the standard chlorothalonil program. Tebuconazole increased yield 804 kg/ha (716 lb/ac) over the standard fungicide. Chlorpyrifos increased yield 503 kg/ha (448 lb/ac) for a net return of $315/ha ($128/ac) in the standard fungicide program. However, in the developmental program, chlorpyrifos increased yield only 79 kg/ha (70 lb/ac) for a net return of -$2/ha (-$1/ac). Labeling of ergosterol biosynthesis inhibitor (EBI) fungicides such as tebuconazole would significantly affect peanut insect management in some production areas by reducing the economic incentive for preventative treatments of organophosphate insecticides.

Fall emergence of Hessian fly, (HF) Mayetiola destructor (Say), was measured from wheat stubble subjected to combinations of spring burning and tillage, and fall tillage in the South Carolina Coastal Plain. In a split-plot experiment, the main-plot effect was a spring treatment, consisting of either: no-tillage, burning, disking, burning and disking or bottom-plowing. The subplot effect was fall tillage (either disking or no-tillage). Among the spring treatments, burning alone gave no reduction in HF emergence. Spring disking reduced HF emergence 54%. Spring burning plus disking reduced emergence 70–96%. No emergence was detected from the bottom-plowed treatments. Fall disking reduced emergence 48–50% in plots that had no spring tillage. Plots disked in both the fall and spring had the same level of HF emergence as plots disked only in the spring or only in the fall. Fall disking greatly increased emergence (up to 23×) from plots where HF had been effectively buried in the spring (previously burned and disked). The disk harrow is the primary tillage implement in the southeastern Coastal Plain, and disking wheat stubble substantially reduced HF emergence. However, repetitive disking can be of limited value or detrimental, in reducing HF emergence from some Coastal Plain soils, in that previously buried puparia might be returned to the soil surface. There was no apparent effect of tillage on emergence timing.

A survey of threecornered alfalfa hopper, Spissistilus festinus (Say) (Hemiptera: Membracidae), damage in 60 South Carolina peanut, Arachis hypogaea L., fields showed that 89 and 58% of plants had feeding girdles during 2003 and 2004, respectively. Use of a foliar insecticide for other target pests reduced hopper damage. Hopper damage was not affected by sampling distance from the field edge; therefore, injury was adequately assessed at 10 m from field borders. In-furrow insecticide choice, planting date, soil texture, previous crop, or tillage did not measurably affect girdling. Subsequent field experiments demonstrated a cultivar effect on threecornered alfalfa hopper injury, with the standard runner-type cultivar ('Georgia Green') more susceptible than the standard Virginia-type ('NC-V11'). More than 50% of stem girdling occurred on the basal quarter (first five internodes) of the plant. Most feeding occurred on secondary branches of main and lateral stems. Weekly sampling of seven grower fields showed that adult hoppers colonize peanut during June and produce two generations on peanut. Only low levels of plant girding were observed in June, but plant girdling increased gradually through late July, when girdling markedly increased contemporary with peak populations of first generation nymphs and adults. A second increase in plant girdling, observed in early September, coincided with the second generation of nymphs on peanut. Foliar treatments at 45- 60 d after planting (DAP) were most effective in suppressing injury. Granular chlorpyrifos treatment also suppressed hopper injury. There was no yield response to insecticide treatments at the hopper injury levels in these tests (up to six girdles per plant). Although the economic injury level (EIL) for this pest has not been defined, our data indicate that a critical interval for monitoring hopper activity is the first 3 wk of July, before the occurrence of significant injury. Where growers have a consistent risk of economic injury, applying foliar treatment in mid-July would be most effective in suppressing damage.

Pitfall traps placed in South Carolina peanut, Arachis hypogaea (L.), fields collected three species of burrower bugs (Cydnidae): Cyrtomenus ciliatus (Palisot de Beauvois), Sehirus cinctus cinctus (Palisot de Beauvois), and Pangaeus bilineatus (Say). Cyrtomenus ciliatus was rarely collected. Sehirus cinctus produced a nymphal cohort in peanut during May and June, probably because of abundant henbit seeds, Lamium amplexicaule L., in strip-till production systems. No S. cinctus were present during peanut pod formation. Pangaeus bilineatus was the most abundant species collected and the only species associated with peanut kernel feeding injury. Overwintering P. bilineatus adults were present in a conservation tillage peanut field before planting and two to three subsequent generations were observed. Few nymphs were collected until the R6 (full seed) growth stage. Tillage and choice of cover crop affected P. bilineatus populations. Peanuts strip-tilled into corn or wheat residue had greater P. bilineatus populations and kernel-feeding than conventional tillage or strip-tillage into rye residue. Fall tillage before planting a wheat cover crop also reduced burrower bug feeding on peanut. At-pegging (early July) granular chlorpyrifos treatments were most consistent in suppressing kernel feeding. Kernels fed on by P. bilineatus were on average 10% lighter than unfed on kernels. Pangaeus bilineatus feeding reduced peanut grade by reducing individual kernel weight, and increasing the percentage damaged kernels. Each 10% increase in kernels fed on by P. bilineatus was associated with a 1.7% decrease in total sound mature kernels, and kernel feeding levels above 30% increase the risk of damaged kernel grade penalties.

Aphid (Homoptera: Aphididae) seasonal flight activity and abundance in wheat, Triticum aestivum L., and the significance of aphid species as vectors of barley yellow dwarf virus were studied over a nine-year period in the South Carolina coastal plain. Four aphid species colonized wheat in a consistent seasonal pattern. Greenbug, Schizaphis graminum (Rondani), and rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki), colonized seedling wheat immediately after crop emergence, with apterous colonies usually peaking in December or January and then declining for the remainder of the season. These two aphid species are unlikely to cause economic loss on wheat in South Carolina, thus crop managers should not have to sample for the subterranean R. rufiabdominalis colonies. Bird cherry-oat aphid, Rhopalosiphum padi (L.), was the second most abundant species and the most economically important. Rhopalosiphum padi colonies usually remained below 10/row-meter until peaking in February or March. Barley yellow dwarf incidence and wheat yield loss were significantly correlated with R. padi peak abundance and aphid-day accumulation on the crop. Based on transmission assays, R. padi was primarily responsible for vectoring the predominant virus serotype (PAV) we found in wheat. Pest management efforts should focus on sampling for and suppressing this aphid species. December planting reduced aphid-day accumulation and barley yellow dwarf incidence, but delayed planting is not a practical management option. English grain aphid, Sitobion avenae (F.), was the last species to colonize wheat each season, and the most abundant. Sitobion avenae was responsible for late-season virus transmission and caused direct yield loss by feeding on heads and flag leaves during an outbreak year.

Three rates of NTN 33893 240 FS seed treatment were compared to a standard of Disyston 15 G in-furrow for suppression of HF, aphids, and barley yellow dwarf virus (BYDV) symptoms. The test was planted 13 Nov on a Marlboro sandy loam in Barnwell County, SC. The experimental design was a RCB with 5 replicates. The experimental unit was a plot 50 x 5.3 ft (8 rows on 8 inch spacing). Granular Disyston was placed in-furrow with electric Gandy applicators. Seed treatments were made by adding 40-ml total volume dilutions of 6 lb of seed and thoroughly mixing in a plastic bag. HF counts were taken by randomly uprooting 10 plants from each of 4 plots (40 plants/treatment) and examining them in the laboratory for larvae and puparia. Aphids were sampled on 3 Feb by counting aphids on 2, random 6-inch samples per plot in 4 replicates (8/treatment). Aphid counts on 9 Mar were taken by shaking wheat plants from 6 inches of row into a sheet metal sampler, (2 samples/e.u., 8 samples/treatment) which extended beyond the full length of the plants. Specimens which could not be field identified were returned to the laboratory for microscopic examination. BYDV ratings were determined by counting the number of symptomatic flag leaves from four 50-ft rows (200 row ft) per plot (1,000 row ft/treatment). These were converted to % based on 2, random 1 m culm counts per plot. Yields were taken by harvesting the middle 6 rows with an Almaco plot combine.

At planting insecticide applications were made to fungicide treated wheat seed in 3 tests conducted on a Marlboro sandy loam in Barnwell County, SC. The experimental design was a RCB with 5 replicates. The experimental unit was a plot 50 x 5.3 ft (8 rows on 8 inch spacing). Hessian fly (HF) resistant varieties (Pioneer 2555, Test 1 and 2; Coker 9835, Test 3) were used to avoid HF yield effects. Granular insecticides were placed in-furrow with electric Gandy applicators. Disyston 8 was applied in-furrow with a CO2 pressurized aluminum manifold delivering 11.1 gal/acre at 25 psi through plastic irrigation tubing (1 mm i.d.). Broadcast application of Disyston 8 was made with a CO2 pressurized boom (10 gal/acre at 25 psi, Teejet 8001 flat fan nozzles) mounted in front of the double-disk openers. Fungicide seed treatments were applied by the Gustafson Seed Research laboratory (Tests 1 and 2) or by a commercial seed treater (Test 3). The NTN 33893 seed treatment was applied by thoroughly mixing a 40 ml-dilution with 6 lb of seed in a plastic bag. Stand and head counts were taken from 2 random 1-m samples per plot. Yields were taken by harvesting the middle 6 rows with a Almaco plot combine.

Granular soil insecticides were evaluated in standard (Bravo) and alternative (Folicur, Moncut, and Tilt) fungicide programs for effects on pod damage, disease incidence, and yield. The test was conducted on a Varina loamy sand in Barnwell County, SC. The experimental design was a RCB with 6 replicates. The experimental unit was a plot 50 × 25 ft (8 rows on 38-inch spacing). Granular insecticides were applied at pegging (Jul 12, 53 DAP) with a 2-row electric Gandy applicator, using 5-inch banders centered over the row. Foliar fungicides were applied with a tractor-mounted 8-row boom (8003 nozzles, 40 psi, 16.9 gpa for the first 2 appl. dates; TX6 nozzles, 60 psi, 8.3 gpa for the last 4 appl. dates). Tire traffic was confined to rows 1—2 and 7—8 of each plot so there was no traffic on yield rows after granular insecticide application. Insect pod damage was evaluated after digging by examining four 25-pod samples per plot and recording external hull feeding and internal kernel damage. The external injury counts reported include those pods with internal injury. Pod injury was primarily due to wireworm feeding based on recovery of 1.0 wireworm larvae/ft2 from 4-in depth sieve samples taken on Sept 6. Disease incidence was evaluated within 1 h of digging by scanning 100 row ft per plot and estimating the total row ft symptomatic for southern stem rot (Sclerotium rolfsii) on the plant crown and Rhizoctonia limb rot on plant laterals. No measure of disease severity was taken. The middle four rows (two 100-ft subsamples per plot) were harvested for yield.

Granular soil insecticides were evaluated in standard (Bravo) and developmental (Folicur or Moncut) fungicide programs for effects on LCB damage, disease incidence, and yield. The test was conducted on a Marlboro sandy loam in Barnwell County, SC. The experimental design was a RCB with 5 replicates. The experimental unit was a plot 50 × 25 ft (8 rows on 38-inch spacing). Granular insecticides were applied with a 2-row electric Gandy applicator, using 5-inch banders centered over the row. Foliar fungicides were applied with a tractor-mounted 8-row boom (8003 nozzles, 40 psi, 20.8 gal/acre for first 3 appl. dates; TX6 nozzles, 60 psi, 12 gal/acre for last 4 appl. dates). Traffic lanes were confined to rows 1-2 and 7-8 of each plot so there was no traffic on yield rows after granular insecticide applications. LCB damage counts were taken on 19 Jul by uprooting 2 plant clumps (1-4 plants/clump) per plot, and counting LCB feeding sites on plant crowns and laterals. LCB damage was evaluated again on 30 Aug by uprooting 1 row ft at 2 sites per plot, and counting LCB scarified pods. Pod damage was evaluated at harvest by counting external and internal pod injury on four 25-pod samples per plot within 24 h of digging. Disease incidence was evaluated within 1 h of digging by scanning 100 row ft per plot and estimating total row ft with white mold symptoms at the plant crown. Yields were taken from 100 row ft per plot.

Gaucho 480 seed treatments were compared to a standard Di-Syston 15 G in-furrow treatment for suppression of barley yellow dwarf virus (BYDV) and yield improvement. Insecticide combinations with Baytan/Captan fungicide seed treatments were also evaluated for effects on seedling emergence, final stand and culm count. The test was planted 9 Nov on a Marlboro sandy loam in Barnwell County, SC. Soil temperature was 66°F at 1.5 inch depth and moisture was excellent. The experimental design was a RCB with 4 replicates. The experimental unit was a plot 50 × 4 ft (6 rows on 8-inch spacing). Granular Di-Syston was placed in-furrow with electric Gandy applicators. Seed treatments were applied by the Gustafson Seed Research Laboratory. All seed were from the same lot. Stand and head counts were taken from 2 randomly-selected 1.0 m samples per plot. Aphid counts were taken from 2 randomly selected 0.5-row ft samples per plot on 19 Feb. BYDV symptomatic flag leaves were counted by 2 observers, each scanning 100 row ft per plot on 19 Apr. The entire plot was harvested for yield.

At-planting insecticide applications were made to winter wheat seeded 1 Nov in a Dothan sandy loam in Barnwell County, SC. The experimental design was a randomized complete block with 5 replicates. The experimental unit was a plot 50 × 5.3 ft (8 rows on 8 inch spacing). Granular Di-Syston and Thimet were placed in-furrow with electric Gandy applicators. In-furrow applications of Di-Syston 8 were made with a CO2 pressurized canister connected to an aluminum manifold having 8 brass push-in fittings. Equal lengths of plastic irrigation tubing (1 mm internal diam) delivered insecticide to the open furrow at 11.1 gal/acre, 25 psi manifold pressure. Broadcast applications of Di-Syston 8 were made from a CO2 pressurized canister connected to a boom mounted in front of the double-disk openers. The system delivered 10.1 gal/acre at 25 psi through Teejet 8001 flat fan nozzles. Broadcast foliar treatments of NTN 33893 were made with a tractor-mounted CO2 pressurized boom (Teejet TX 6 nozzles, 7.3 gal/acre at 50 psi). A previously untreated set of plots was Sed with NTN 33893 on 9 Jan and a set of plots previously treated with Di-Syston 15 G in-furrow was Sed with NTN 33893 on 12 Mar. Hessian fly samples were taken by randomly uprooting 10 plants from each of 4 plots (40 plants/treatment) and dissecting them in the laboratory. Aphid counts were made from 2 random 6-inch samples per plot (8/treatment). HF activity was monitored wkly in a separate set of plots by sampling 40 leaves for egg deposition and dissecting 40 plants for larval and puparial counts. Aphid species populations were also monitored wkly in a separate set of plots. EGA and BCOA were predominant throughout the growing season. On the 3 Mar sampling date, BCOA comprised 64% of the population and EGA the remainder. Yields were taken by harvesting the middle 6 rows with an Almaco plot combine. All treatments were planted with the same seed lot.

Seed treatments of dimethoate, Orthene 75 S, and NTN 33893 240 FS were compared to standard in-furrow treatments of Di-Syston 15 G and Thimet 15 G for HF efficacy. The test was planted 26 Oct in Barnwell County, SC, on a Dothan sandy loam. The experimental design was a randomized complete block with 5 replicates. The experimental unit was a plot 50 × 5.3 ft (8 rows on 8 inch spacing). Granular Di-Syston and Thimet were placed in-furrow with electric Gandy applicators mounted centered on the drill. Orthene 75 S seed treatments were applied by thoroughly mixing the appropriate amt of dry insecticide with 5 lb of seed in a plastic bag. Dimethoate (Clean Crop 2.67 EC) seed treatments were diluted with the appropriate amt of water, to a total vol of 30 ml and thoroughly mixed with 5 lb of seed in a plastic bag. The NTN 33893 treated seed were provided by Mobay and were from a different seed lot of the same variety. All other treatments were from the same bag of seed. Phytotoxicity evaluations were made at 11 and 19 d after planting by taking stand counts from two random 1 m row samples per plot. HF efficacy was evaluated by uprooting 10 randomly selected plants from each of 4 plots (40 plants/treatment) and examining them in the laboratory for larvae and puparia. The middle 6 rows were harvested with an Almaco plot combine for yield and test wt. All yields were corrected to 13.5% moisture.