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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.

‘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.

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 (

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.

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.