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A semiselective, diagnostic agar medium (T-5) and low temperature incubation technique were developed for recovering Pseudomonas viridiflava from the environment or plant material. Medium T-5 contains the following per liter: NaCl, 5.0 g; NH4H2PO4, 1.0 g; K2HPO4, 1.0 g; MgSO4·H2O, 0.2 g; D-tartaric acid, 3.0 g; phenol red, 0.01 g; agar, 20.0 g; bacitracin, 10 mg; vancomycin, 6 mg; cycloheximide, 75 mg; novobiocin, 45 mg; penicillin G, 5 mg. The pH is adjusted to 7.4. Antibiotics are added aseptically after autoclaving. P. viridiflava recovery from artificially infested, field-soil (Tifton loamy-sand), with a cropping history of no onion production, was high, with a corresponding reduction of 99.99% of nontarget bacteria. However, soils from fields with a long history of onion production, near Vidalia, Georgia, contained significantly larger populations of background microflora that grew on medium T-5. Incubation at 5°C reduced contaminating microflora 1,000- to 10,000-fold with no reduction in recovery of the target organism. However, this low temperature incubation required an increased incubation period of 3 weeks and reduced the level of fluorescence of P. viridiflava.

Identifying effective weed control regimes for organic peanut is paramount for improving the feasibility of organic production. Tine cultivation is a proven effective method for reducing in-row weed populations in several crops. Field trials were therefore conducted in 2008 and 2009 to assess the effects of tine cultivation combined with sweep cultivation and supplemental hand-weeding on weed control and overall productivity of two peanut cultivars under organic management. Tine cultivation regimes consisted of two frequencies (once per week or twice per week) for three durations (3 wk, 4 wk, or 5 wk). All cultivation treatments were also cultivated with flat sweeps at least once and hand-weeded periodically during the growing season. A non-cultivated, non-weeded control was included for comparison. All cultivation treatments significantly reduced annual grass populations in 2008 and Florida pusley populations both years. Cultivated treatments also resulted in denser plant stands for peanut (9.2 plants/m to 13.2 plants/m) than the non-cultivated control (5.9 plants/m to 7.9 plants/m). Pod yields in cultivated treatments ranged from 3502 kg/ha to 3823 kg/ha and were all significantly greater than yields in the non-cultivated control (1630 kg/ha). Also, net revenues generated by cultivated treatments ranged from ($3333/ha to $3637/ha) and were greater than that of the control ($1795/ha). Cultivation frequency had little effect on weed control and peanut productivity. However, the 4- and 5-wk durations displayed potential for improving peanut yield, grade, and net revenue over the 3-wk duration, especially when annual grass weeds were predominant. Cultivating once weekly for 4 or 5 wk with a tine cultivator, along with at least one sweep cultivation and supplemental hand-weeding, is a viable, economical option for providing adequate weed control and maximizing productivity of organically-managed peanut at current market premiums.

Experiments were conducted during 2000 and 2001 at a total of 13 locations throughout Alabama, Georgia, Florida, North Carolina, and Texas to evaluate efficacy of herbicides at or below the manufacturer's suggested use rate. Herbicide applications included diclosulam and flumioxazin applied PRE alone or followed by imazapic applied early postemergence (EPOST). All possible combinations of diclosulam at 0, 13.5, or 27 g ai/ha and flumioxazin at 0, 53, or 105 g ai/ha applied PRE were included. Imazapic was applied at 35 g ai/ha. Ivyleaf morningglory was controlled more than 87% when imazapic was applied EPOST regardless of PRE herbicide. Pitted morningglory control > 67% was observed with applications of diclosulam (27 g/ha) followed by imazapic, diclosulam (13.5 g/ha) plus flumioxazin (53 g/ha), diclosulam (13.5 g/ha) plus flumioxazin (105 g/ha), and diclosulam (27 g/ha) plus flumioxazin (105 g/ha). Sicklepod was controlled more than 74% with flumioxazin (53 g/ha) followed by imazapic and diclosulam (27 g/ha) plus flumioxazin (105 g/ha) followed by imazapic. Florida beggarweed was controlled more than 84% by all PRE herbicide combinations except flumioxazin (53 g/ha) alone or diclosulam (27 g/ha) alone or with imazapic. Yellow nutsedge was controlled at least 90% with diclosulam at either rate followed by imazapic and by diclosulam plus flumioxazin followed by imazapic regardless of rate. Pod yield was generally higher when herbicides were applied regardless of herbicide combination or rate. Peanut yield was maximized with the lowest rates of flumioxazin or diclosulam PRE followed by imazapic EPOST.

The effects of chlorimuron application timing on the development of spotted wilt disease of peanut caused by tomato spotted wilt tospovirus was studied in fifteen field trials in Georgia from 2000 through 2007. Chlorimuron at 9 g ai/ha was applied to new peanut cultivars at various intervals ranging from 60 to 105 days after emergence (DAE) under weed-free conditions. When averaged over chlorimuron application timings, AP-3, and Georgia-02C had less spotted wilt incidence than Georgia Green but only AP-3 produced yields equivalent to Georgia Green. AT-201 had significantly higher levels of spotted wilt and 44% lower yields when compared to Georgia Green. Spotted wilt incidence of Georgia-03L did not differ from Georgia Green but the yields of GA-03L were 24% lower than Georgia Green. Differential tolerance of peanut cultivars to chlorimuron was not observed. When averaged over cultivars, chlorimuron applied at 60–69 DAE, 70–79 DAE, or 90–99 DAE increased the incidence of spotted wilt by 6–9%. However, peanut yields were not reduced by any application of chlorimuron.

A series of replicated field experiments was conducted with vegetable soybean (edamame), Glycine max (L.) Merrill, to assess the impacts of cultivars, planting dates, and insecticidal controls on insect pest abundance, crop damage and yield potential. The velvetbean caterpillar, Anticarsia gemmatalis Hübner, was the most common lepidopteran defoliator in this study, causing heavy defoliation in some years when left untreated. Other lepidopterans observed included the soybean looper, Pseudoplusia includens (Walker), and the green cloverworm, Hypena scabra (F.). Stink bugs, primarily the southern green stink bug, Nezara viridula (L.), also caused seed damage in some cultivars when left untreated. Stink bug damage exceeded expectations on edamame seeds when exposed to moderate stink bug densities (≤3 bugs per 25 sweeps). Other arthropods that were commonly observed included threecornered alfalfa hoppers, Spissistilus festinus (Say), grasshoppers, Melanoplus spp., and the potato leafhopper, Empoasca fabae (Harris). Arthropod infestations on edamame were similar to reported pest problems on conventional soybeans being produced for oil and meal. Midseason applications of the insecticides diflubenzuron plus l-cyhalothrin reduced insect pest populations, percentage of arthropod-induced defoliation and percentage of seeds damaged by stink bugs, but had little effect on edamame yields. Most defoliation and seed damage occurred during R5 development when seeds were approaching full size, thus only minimal yield reductions were noted. However, seed quality of the untreated vegetable soybeans would be unacceptable for the consumer. Total fresh green yields ranged from 2343–11,895 kg ha−1, depending on year, cultivar and planting date, whereas fresh green seed yields ranged from 1208–6,119 kg ha−1. Early-maturing edamame cultivars planted in April had fewer insect pests and less damage than the cultivars planted later. Avoidance of insect pests is an important production consideration for insect management, especially critical in an organic production system. The fresh green seed yields produced during this study demonstrate that this emerging alternative crop has the potential for economic success in the southern region, assuming that the arthropod pests are effectively managed to maintain acceptable edamame quality and yield.

Idiopathic pulmonary fibrosis (IPF) is a challenging and frustrating disease for clinicians and patients confronted with this clinical entity, since it is associated with a dismal ∼3-yr median survival from the time of diagnosis 1 and an effective treatment regimen is yet to be determined. The lack of an effective treatment option has encouraged investigation of new treatment regimens, and promising agents are being investigated in several clinical trials worldwide. Despite aggressive, worldwide collaborations in pursuit of an effective regimen, significant progress is still needed to recommend a specific treatment regimen for IPF 2. While recent publications have provided insights regarding appropriate outcome measures chosen as end points for IPF clinical trials, results from these studies have either (unfortunately) been negative or merely provided positive signals and generated hypotheses that deserve to be investigated further in well-designed studies 3–6. Investigators who are involved in planning IPF studies face daunting challenges in selecting outcome measures that will appropriately allow statistical assessment of clinically meaningful effects or outcomes. Clinicians reviewing the IPF literature are confronted with equally daunting challenges in interpreting the clinical and statistical importance of these findings and applying this knowledge in the clinical care of their patients. Both the investigator and the clinician interpreting the results need to understand how IPF disease severity and progression are best measured in order to provide the most convincing and interpretable study evidence. The 2000 International Consensus statement for IPF diagnosis and treatment suggests measures with promise for measuring IPF disease extent and potential for measuring change, but it is clear that validated outcome measures were not known when the document was drafted 1. Investigators involved in the largest IPF trial conducted to date recently reported an apparent lack of appropriate IPF outcome measures 6. They reported …

Idiopathic pulmonary fibrosis (IPF) is a relentlessly progressive disease with a median survival of approximately 3 yrs. Measurements of airflow and lung volumes at rest are generally used to monitor the clinical course in this disorder. This study was designed to determine if a modified version of the 6-min walk test, called the timed walk test, accurately characterises disease severity and survival in IPF. The study population consisted of 28 patients with well-characterised progressive IPF. The timed walk test and concurrent measures of disease severity were assessed at baseline. Participants were prospectively followed for > or =4 yrs to determine the relationship between parameters of the timed walk test and survival. There were strong correlations between the end-exercise saturation and walk-velocity parameters of the timed walk test and diffusing capacity, and arterial oxygen tension at rest. In univariate Cox proportional-hazards models, end-exercise saturation, change in saturation with exercise, walk distance and walk velocity were associated with survival. In unadjusted logistic regression models, odds of death at 2 yrs were associated with the same parameters. In conclusion, the timed walk test relates to disease severity and long-term outcome in progressive idiopathic pulmonary fibrosis.

In the laboratory, excessive variability in molybdate reactive phosphorus (MRP) concentrations in water extracts of poultry litter that appeared to be associated with storage by freezing was frequently observed. In one experiment, repeated twice, the effects of a factorial combination of storage temperatures [freezing (−16 to −15°C) or room temperature (21–24°C)] was studied for 60–62 h with poultry litter type (three broiler and one pullet) on MRP concentrations in water extracts. An additional experiment was conducted to compare the effects on phosphorus (P) concentration of a 1 mg P L−1 standard of spiking with 1 mg L−1 of Fe+3 or Al+3 and storage under room temperature or freezing for two and five days. No statistical differences were observed in MRP levels of extracts kept at room temperature measured immediately after the extraction, after 62 h or eight days. Freezing, however, consistently decreased MRP concentrations measured immediately after thawing compared to measurements in extracts ...

Field studies were conducted in various peanut growing regions of Texas and Georgia to study peanut response to flumioxazin alone or in combination with dimethenamid or metolachlor. In south Texas during 1997, flumioxazin plus metolachlor resulted in greater than 45% peanut stunt, while flumioxazin plus dimethenamid caused ≤20% peanut stunt. This stunting was attributed to cool, wet growing conditions. Peanut yields in flumioxazin plus metolachlor-treated plots were reduced 58% from peanut in the non-treated check. In 1999 and 2000, flumioxazin plus dimethenamid or metolachlor resulted in 15% or greater peanut stunt, but stunting was not constant across weather conditions or locations. In west Texas and Georgia no peanut stunting with flumioxazin was noted. At the Levelland, TX location, flumioxazin at 0.07 kg/ha plus metolachlor at 1.1 kg/ha reduced peanut yield 32% when compared with the non-treated check; while at the Pearsall, TX location, metolachlor or dimethenamid at 1.1 kg/ha, flumioxazin at 0.07 kg/ha plus dimethenamid at 1.5 kg/ha, and flumioxazin at 0.1 kg/ha plus dimethenamid at 1.1 kg/ha reduced peanut yield 24 to 48% when compared with the non-treated check. No yield reduction was noted in Georgia.

The tobacco thrips, Frankliniella fusca (Hinds), is an economic pest of flue-cured tobacco because it vectors tomato spotted wilt tospovirus. Other species of thrips are also vectors of spotted wilt in tobacco, including the western flower thrips, F. occidentalis (Pergande). This study examined the presence of thrips species on alternate plant hosts associated with the tobacco farmscape and surrounding area. Weed hosts were sampled from December through April from 1998 through 2001 to assess which plants provide suitable refuge and nutrients for thrips survival, reproduction, and spotted wilt infection. Thrips were identified to species and confirmed as potential vectors of spotted wilt by using ELISA to test for the presence of a non-structural tomato spotted wilt virus protein. Wild radish (Raphanus raphanistrum L.), broomsedge (Andropogon virginicus L.), and narrowleaf vetch (Vicia sativa L. subsp. nigra (L.) Ehrh.) are common late-winter weeds in the farmscape that harbor spotted wilt vectors. Cutleaf evening primrose, Oenethera laciniata Hill, and volunteer soybean, Glycine max(L.) Merrill, also were hosts of spotted wilt vectors in the tobacco farmscape. Numerous other weed hosts were present in the tobacco farmscape but either had no thrips collected from them or thrips were not confirmed as potential spotted wilt vectors from these host plants. Several other plants near the tobacco farmscape also were infected with spotted wilt, and three of these host plants, common chickweed (Stellaria media (L.) Cyrillo), carrot (Daucus carota L.), and flowering dogwood (Cornus florida L.) had confirmed vectors (ELISA) collected from them. Henbit (Lamium amplexicaule L.), wild radish, cutleaf evening primrose, narrowleaf vetch, carrot, curly dock (Rumex crispus L.), red sorrel (Rumex acetosella L.), and common chickweed were confirmed as positive plant hosts in this study for spotted wilt using ELISA. Frankliniella fusca appears to be the most abundant thrips vector on these alternate plant hosts and is the predominate thrips species collected on the flue-cured tobacco, Nicotiana tabacum L. However, F. occidentalis, Haplothrips graminis Hood, and Chirothrips spp. also were confirmed in this study to be potential vectors in the tobacco farmscape. Weed hosts in the farmscape appear to be influential as refuge and nutrients for vectors and an innoculant source of tomato spotted wilt virus in the flue-cured tobacco farmscape.

Imazapic, diclosulam, and flumioxazin have been registered for use in peanut since 1996. These herbicides provide substantial residual control of broadleaf weeds in peanut. A comprehensive review was conducted for these residual herbicides to determine their role in future weed control systems in peanuts. Weed control data for research from over 100 experiments conducted from 1990–2000 by Georgia, Florida, and Auburn Universities and USDA-ARS scientists were compiled. Residual herbicide systems evaluated were imazapic postemergence (POST) at 71 g ai/ha, flumioxazin preemergence (PRE) at 70, 87, and 104 g ai/ha, diclosulam preplant incorporated (PPI) and PRE at 18 and 26 g ai/ha, and paraquat plus bentazon early POST (EPOST). Other treatments included the residual herbicides used in combination with paraquat plus bentazon EPOST, for a total of 17 treatments. Regionally important weeds were selected and included: sicklepod, Florida beggarweed, purple and yellow nut-sedge, Ipomoea morningglory species, and smallflower morningglory. Sicklepod control with imazapic alone was 86% (50 tests), 73% (25 tests) with paraquat plus bentazon, and 63% or less with diclosulam and flumioxazin regardless of rate. Florida beggarweed control was 90% (29 tests) with flumioxazin (104 g/ha PRE); 78% (50 tests) with diclosulam 26 g/ha PPI; 72% (72 tests) with imazapic; and 70% (40 tests) with paraquat plus bentazon. Purple and yellow nutsedge control was 90% with imazapic. Yellow nutsedge control was 78% (18 tests) with diclosulam (26 g/ha PRE) and less than 69% with flumioxazin and paraquat plus bentazon. Paraquat plus bentazon increased weed control over residual herbicides alone.

Field trials were conducted in Georgia, North Carolina, and Texas to evaluate the effects of preplant applications of 2,4-D, dicamba, tribenuron, and tribenuron plus thifensulfuron on peanut yield. Herbicides were applied 30, 15, 7, or 0 d before planting (DBP) in conventional production systems in Georgia and Texas, and 28, 21, 14, 7, and 0 DBP in no- and strip-tillage systems in North Carolina. Amine and ester formulations of 2,4-D did not affect peanut yield at any time of application in any state. Dicamba reduced peanut yield when applied at 0 DBP in two of seven trials. Tribenuron did not affect peanut yield regardless of preplant interval. However, tribenuron plus thifensulfuron reduced yields when applied at 7 DBP in one of five trials. These data suggest that 2,4-D, tribenuron, and tribenuron plus thifensulfuron can be safely used for preplant weed control in peanut when applied 7 DBP. Dicamba should be applied a minimum of 15 DBP.

Introduction Higher education institutions are escalating their efforts to meet the growing demand for expanded educational opportunities. More and more students are demanding course delivery schemes that are not time and place specific. The emergence of distance education as a course delivery mode is quite evident in our culture. Distance education advocates argue that its rapid expansion is part of the technological revolution on campuses, and institutions that are not "with the program" will be left behind. Others see distance education as a cornucopia for survival in times of low enrollment and budget restraints. Higher education administrators enthusiastically herald the technological revolution that is sweeping American campuses. Department chairs put pressure on faculty to use technology in their teaching, and to participate in distance education. Concomitantly, little thought is given to such issues as research/ publishing demands, teaching load, promotion/tenure, or time-on-task (Higher Education Research Institute, 1999). Rockwell, Schaeur, Fritz, and Marx (1999) identified five obstacles to teaching from a distance (1) time requirements, (2) time taken from research, (3) training requirements, (4) developing effective technology skills, (5) assistance with on-line course design and delivery. At the heart of the above obstacles lie considerations that form the lifeblood of survival in academia--time for research and publishing. The prudent faculty member would be wise to focus on the components of the academic regimen that ensures inclusion and longevity in the system. Teaching, research and service form the trilogy of credible activity that generally guides promotion and tenure in American academia. The most vulnerable to abuse are the junior faculty who must, in addition to showing yearly progress, make themselves available for additional assignments, thus diminishing their ability to do "scholarly" work. Current research directing higher education toward practical solutions to the distance education mindset seems, at the moment, limited. Ehrmann (1997) suggested that current research has failed to ask the right questions when comparing traditional teaching to distance education. He further proposes that until a full accounting is made of the innumerable and complex variables linked to distance education, decisions will continue to be flawed. The Institute for Higher Education Policy (2000) identified four complex variables that must be addressed in quality distance education programs (1) encouragement to use technical assistance in course development, (2) assistance in transition from traditional to distance learning, (3) available support, and (4) assistance and training. Deciding to embrace distance education may bring accolades from department chairs; however, it is also important to note the paradigm shift when getting the job done is actually considered. Hanna (1999) suggested that the technologies of distance education have changed, but attitudes remain the same. Recent distance education literature has both recommended and described the kinds of paradigm changes needed for the successful implementation of distance education (Hanna, 1999; Higher Education Research Institute, 1999; Institute for Higher Education Policy, 2002; McKenzie, 2000). Schifter (2000) went further to identify two critical parts of the distance education infrastructure that seem contravening, at first glance, but make prefect sense upon closer examination--the art of teaching, on the part of the teacher, and--the art of learning, on the part of the student. The art of teaching involves both motivation to change and efficacy. There is less motivation for change among senior-level faculty than junior-level faculty, (Rockwell, Schauer, Fritz, and Mark, 2000). Senior--level faculty is more inclined to use their traditional style of teaching than to embrace newer ones. They generally feel uncomfortable with the new technology. …

Studies were conducted from 1999 through 2001 in Georgia to develop Texas panicum management systems in strip-tillage peanut production into a killed rye cover crop. The experimental design was a split-plot with four replications. Main plots were preemergence (PRE) herbicides for annual grass control—ethalfluralin, pendimethalin, metolachlor, alachlor, dimethenamid, and a nontreated PRE control. All plots were irrigated immediately after PRE applications to activate herbicides. Subplots were postemergence (POST) graminicides applied 28 d after peanut emergence—sethoxydim, clethodim, and a nontreated POST control. POST graminicides were applied with a crop oil concentrate. None of the PRE herbicides alone adequately controlled Texas panicum in strip-till peanut production, even with optimum activation with irrigation. Sethoxydim and clethodim controlled Texas panicum at least 91%, regardless of PRE treatments. Peanut yields were greater where ethalfluralin or pendimethalin PRE were applied sequentially with a POST graminicides, compared to PRE herbicides or POST graminicides alone. This suggests that, while POST graminicides effectively control Texas panicum, the reduced efficacy of dinitroaniline herbicides is still beneficial. The additional cost of a POST graminicide needs to be factored into production budgets for strip-tillage peanut production.

Epistasis is a pervasive phenomenon in biology. Nevertheless, attempts at identifying epistatic interactions with quantitative trait loci (QTL) analyses have yielded inconsistent results. In this study, we attempt to determine the genetic control of outbreeding depression and the possible role of epistasis following a wide cross in common bean (Phaseolus vulgaris L.). A recombinant inbred population, derived from a cross between Andean and Mesoamerican common bean cultivars, was evaluated in two markedly contrasting environments. A low-density linkage map based on AFLPs was used to locate QTLs for the number of days to maturity, average daily biomass and seed yield accumulation, and harvest index. Both independently acting and digenic epistatic QTLs of similar magnitude were identified. A majority of the loci involved in these epistatic interactions did not have an independent effect. Although we did find evidence for strong epistatic control of the traits investigated, we also found, in contrast to other recent studies, that there was no evidence for a bias toward coadapted gene complexes at the level of digenic epistasis. We discuss these results in relation to the role of epistasis in the evolutionary history of the species and methodological difficulties in detecting epistasis.

Wild plant species are often adapted to more stressful environments than their cultivated relatives. Roots are critical in exploiting soil resources that enable plants to withstand environmental stresses, but they are difficult to study. Cultivated lettuce (Lactuca sativa L.) and wild L. serriola L. differ greatly in both shoot and root characteristics. Approximately 100 F2:3 families derived from an interspecific cross were evaluated in greenhouse and field experiments. In the greenhouse, root traits (taproot length, number of laterals emerging from the taproot, and biomass) and shoot biomass were measured 4 weeks after planting. In the field, plants were grown for 9 weeks (close to harvest maturity of the cultivated parent); mild drought stress was induced by withholding water for 1 week, and gravimetric moisture of soil was then determined for five depth increments between 0–100 cm. The families were genotyped using codominantly scored AFLP markers distributed throughout the genome. Composite interval mapping was used to analyze marker-trait associations. Quantitative trait loci were identified for differences between wild and cultivated lettuce for root architectural traits and water acquisition. Thirteen QTL were detected that each accounted for 28–83% of the phenotypic variation. The loci for taproot length (i.e., cm taproot length g–1 plant biomass) and the ability to extract water from deep in the soil profile co-localized in the genome. These coincident loci were identified in separate experiments. The wild L. serriola is therefore a potential source of agriculturally important alleles to optimize resource acquisition by cultivated lettuce, thereby minimizing water and fertilizer inputs and ultimately enhancing water quality.

Volunteer peanut and cutleaf eveningprimrose are part of the epidemiology of spotted wilt disease of peanut and other susceptible crops in the Southeastern U.S. Coastal Plain. Studies were conducted on the timing and frequency of fallow harrowing, integrated with applications of glyphosate or tribenuron-methyl, for control of volunteer peanut and cutleaf eveningprimrose. Spring harrowing was generally more effective in controlling volunteer peanut than fall or winter harrowing. Conversely, cutleaf eveningprimrose was controlled by sequential harrowing in the fall, winter, and spring, with single harrowing less effective. In general, spring applications of glyphosate or tribenuron-methyl were equally effective in controlling volunteer peanut and cutleaf eveningprimrose in absence of tillage.

We have developed a program to convert the three dimensional coordinates describing protein structure in the Brookhaven Data Bank into an assignment of secondary structure. The program assigns secondary structure in the same way a person assigns structure visually. It uses two angles and three distances to assign alpha-helix, 3(10)-helix, beta-strand, hydrogen-bonded beta-turn, non-hydrogen-bonded beta-turn, and poly (L-proline) II type 3(1)-helix. The program is concerned with amide-amide interactions and should be particularly useful to spectroscopists.

Tall weeds in peanut fields cause losses other that yield reduction from competition by intercepting fungicides and insecticides, and interfering with harvest efficiency. Studies were conducted at Archer, FL and Tifton, GA in 1994 and 1995 to determine an effective means to selectively control tall Florida beggarweed and sicklepod late season in peanut using herbicides applied with a wickbar. Herbicides evaluated were glyphosate, paraquat, and dimethylalkylamine salt of endothall (DMAA endothall); each applied at 0, 25, 50, 75, and 100% by volume. Treatments were applied in two passes at opposite directions midseason at both locations. Glyphosate and paraquat, at concentrations as low as 25% by volume, effectively controlled Florida beggarweed and sicklepod at both locations. DMAA endothall did not adequately control Florida beggarweed or sicklepod at either location, regardless of rate. Peanut yields were not increased by weed control from any herbicide applied with a wick-bar. The only benefits from late-season Florida beggarweed and sicklepod control with a wick-bar appear to be improved fungicide deposition and more efficient mechanical harvest.

The germplasm of cultivated common bean exhibits a lower level of genetic diversity within each geographical gene pools (Mesoamerican and Andean) compared to that of the respective wild ancestors. Crosses between these two gene pools potentially provide a source of additional genetic diversity but their progenies have been characterized by phenotypic abnormalities and reduced productivity. In order to gain additional insights into this problem, we examined the segregation for performance in two recombinant inbred populations (RIPs) resulting from Mesoamerican × Andean crosses in three contrasting environments and two years. The two RIPs – ‘California Dark Red Kidney’ (of Andean origin) × ‘Yolano’ (Mesoamerican), n = 150, and A55 (Mesoamerican) × G122 (Andean), n = 67 – were grown in replicated field tests to assess the agronomic performance of each recombinant inbred line. Both populations exhibited, on average, greater days to maturity (DTM), lower biomass growth rate (above-ground dry weight/DTM), lower economic growth rate (seed yield/DTM), and lesser harvest index. In contrast with the conclusions of earlier experiments, there was no evidence from the field trials for a genetic association (due to linkage or pleiotropy) between seed weight and economic growth rate, but there may be a genetic association between seed weight and life cycle length. We compare the results of these studies with earlier experiments on inter-gene pool recombinant populations of common beans and relate our observations of diminished performance to models of speciation mechanisms.

Greenhouse studies were conducted in 1995, 1996, and 1998 to measure the effect of preplant incorporated (PPI) and preemergence (PRE) applications of ethalfluralin and pendimethalin on growth of individual peanut seedlings in pots. Herbicide rates evaluated were 0, 0.6, 1.1, and 2.2 kg ai/ha for each herbicide. Parameters measured were time of emergence, seedling height, canopy width, foliage biomass, root length, and root biomass of individual plants. PPI applications were more injurious than PRE applications for all parameters regardless of herbicide. Ethalfluralin PPI inhibited peanut seedling growth more than equivalent rates of pendimethalin PPI. However, peanut seedling responses to PRE applications of ethalfluralin and pendimethalin were generally the same.

The influences of bahiagrass, corn, and cotton in rotation with peanut and treatments with aldicarb, flutolanil, and aldicarb plus flutolanil on nematodes, thrips, diseases caused by soilborne fungal pathogens, and yield of peanut were studied for 3 yr. Peanut yields following either 1 or 2 yr of bahiagrass, corn, or cotton were higher than those of continuous peanut. Peanut yield was greatest in the aldicarb plus flutolanil treated plots (5270 kg/ha), intermediate where aldicarb (4060 kg/ha), or flutolanil (4597 kg/ha) was used without aldicarb, and least in untreated (3690 kg/ha) plots. Yield increases in response to cropping sequences and pesticide treatments resulted primarily from suppression of crop damage by Meloidogyne arenaria, Sclerotium rolfsii, Rhizoctonia solani, and Frankliniella spp. The data document the pest management benefits and yield response associated with using two widely grown agronomic crops (corn and cotton), an improved bahiagrass cultivar, and pesticide treatments in peanut production.

Previous reports of a distinctive, fibrous, soft-tissue tumor include eight patients with subcutaneous lesions and six patients with intramuscular lesions. We report a 48-year-old woman with a 2-cm cutaneous and subcutaneous nodule on the left arm with the same histologic features. An excisional biopsy showed a large, well circumscribed tumor replacing the reticular dermis and subcutaneous tissue. The tumor was relatively hypocellular and composed primarily of large, spindled, plump or stellate fibroblasts haphazardly dissecting between thickened fibrotic collagen bundles. The stroma contained a large amount of mucin which was positive with alcian blue at pH 2.5, and relatively numerous mast cells were present. The fibroblastic-like cells were positive with Vimentin and Factor XIIIA and negative with S-100, desmin, actin and keratin.

A semiselective agar medium (T-5) was used to sample environment and plant material as a habitat for Pseudomonas viridiflava. Soil, irrigation water, soybean foliage, and foliage from various weeds in an onion-growing area were assayed over a 5-year period. P. viridiflava was recovered only as an epiphytic resident from weed species that included cutleaf evening primrose, dandelion, common fumitory, purple cudweed, spiny sowthistle, Virginia pepperweed, and wild radish. The bacterium apparently overseasons in association with these weeds, because its presence was detected prior to, as well as during, the onion-growing season. Preliminary tests indicated that weed control may suppress bacterial streak and bulb rot levels.

Studies were conducted in 1994 and 1995 at Headland, AL, Gainesville, FL, and Tifton, GA to quantify peanut injury by ethalfluralin applied preplant incorporated (PPI) or preemergence (PRE) at 0.0, 0.6, 1.1, 2.2, and 4.5 kg ai/ha. Parameters most sensitive to ethalfluralin injury were pod biomass and yield, while time of emergence, stand, canopy width, and foliar biomass were less sensitive. Ethalfluralin was generally more injurious when applied PPI than PRE, especially when rates were ≥ 2.2 kg/ha. At these rates, pod formation was inhibited and yields were reduced with little corresponding effect on vegetative growth. These data show ethalfluralin can be safely applied either PPI or PRE to peanut at rates ≤ 1.1 kg/ha.

B. G. Mullinix, Jr. Coastal Plain Experiment Station, Tifton, GA 37193-0748 Studies were conducted from 1990 through 1994 near Tifton, GA, on the population dynamics of yellow nutsedge and certain annual weeds in peanut-corn and peanut-cotton rotations. Converse rotation sequences were included to eliminate year effects. Continuous fallow plots (noncrop) were included for comparison. Within each crop, including fallow, were 3 levels of weed management: low, moderate, and intensive. Weed densities and numbers of yellow nutsedge tubers were not affected by crop rotations, but they were affected by individual crops and weed management systems in each crop. Fallow plots, including those with intensive fallow weed management using tillage and nonselective herbicides, consistently contained more yellow nutsedge plants and tubers than other plots. Moderate and intensive weed control systems in peanut and cotton reduced yellow nutsedge densities and tubers, but only peanut yields were increased by intensive weed management. Weed management systems did not affect yellow nutsedge densities in corn, although yields were increased by moderate and intensive systems due to improved control of other weeds. Our results suggest that uninterrupted plantings of peanut, corn, or cotton with moderate levels of weed management are generally sufficient to suppress yellow nutsedge and allow for optimum crop yield. If fields are fallow, yellow nutsedge population densities and tubers will increase exponentially, even with intensive fallow weed management.

Alternative genes for resistance to Bean Common Mosaic Virus in common bean (Phaseolus vulgaris L.) are necessary as a result of the recent introduction of necrosis-inducing strains of this virus into the USA. The recessive bc-3 gene confers resistance against all known strains of this pathogen. We describe here experiments to develop a relatively easy-to-use procedure to introgress the bc-3 gene into elite bean cultivars. First, we employed bulked segregant analysis to identify RAPD markers linked to the bc-3 locus. The ROC11/350/420 marker was codominant with the bc-3 gene and the ROC20/460 marker was dominant and linked in trans. A survey of cultivated materials allowed us to identify the likely evolutionary origin of the bc-3 resistance allele as a member of the Mesoamerican gene pool, probably of race Mesoamerica. Polymorphism of the RAPD markers in a Davis common bean mapping population (BAT93 x Jalo EEP558) allowed us to map the markers and, by inference, the bc-3 gene to linkage group D6. Second, we used sequence information from the cloned RAPD fragments to design longer, more reliable PCR primers that differentiate individuals homozygous for the resistance allele from susceptible genotypes in segregating populations of Andean origin. Third, we developed a marker tagging system that used a simplified DNA extraction technique and a PCR-based assay to identify the genotype of common bean plants at the bc-3 disease resistance locus. This simplified marker assisted selection system is expected to eliminate the need for costly quarantines and progeny tests in breeding programs for common bean of Andean origin.

Field studies were conducted at Tifton, GA to quantify phytotoxicity of flumetsulam on peanut as influenced by application rate and timing in a weed free experiment. Flumetsulam PPI at rates up to 0.14 kg ai/ha visibly injured peanut and reduced canopy width, but injury from PPI flumetsulam at 0.07 kg/ha or less was no worse than a standard early postemergence (EPOST) treatment of bentazon (0.6 kg ai/ha) plus paraquat (0.14 kg ai/ha). Flumetsulam EPOST at rates up to 0.07 kg/ha visibly injured peanut and reduced peanut canopy width. Flumetsulam injury at rates of 0.035 kg/ha EPOST was similar to that caused by bentazon plus paraquat. Interactive effects of PPI and EPOST flumetsulam reduced early and mid-season pod and foliage biomass more than either application alone. However, peanut recovered with final yields not affected by flumetsulam, regardless of rate or time of application.

• In 2010 — Elements of NASA's Airspace Systems Program research were aligned with FAA mid-term priorities — Stakeholder feedback on our progress and future goals validated our relevance to their NextGen capabilities

One of the dilemmas in predicting the secondary structure of proteins from their amino acid propensity for a given conformation is the presence of all amino acids in all types of secondary structure, regardless of their propensity for that specific structure. One explanation is the nucleation hypothesis that only a few residues with a strong propensity for the secondary structure, such as the alpha-helix structure, initiates its formation and propagates the structure through indifferent sequences until strong breakers terminate the growth on both ends. Eight 15-mer peptides were studied to examine the alpha-helix nucleation hypothesis. The nucleation sequence of VAEAK, with high helix propensity, was mixed with an indifferent sequence of TSDSR in all possible permutations. From the percent alpha-helix structure derived from the CD at 222 nm, it appears that helicity does not propagate through the indifferent sequence.

A combination of fallow tillage and a March application of carbofuran were assessed as tactics for decreasing survival and reproduction of tobacco thrips overwintering in six harvested peanut fields. Large numbers of tobacco thrips, Frankliniella fusca (Hinds) (Thysanoptera: Thripidae), developed in three fields on volunteer peanut, Arachis hypogaea L., and winter annual weeds. Adult tobacco thrips collected during the late winter were predominantly brachypterous, with percent brachyptery averaging 71–95% for females. Brachypterous adults tended to be more abundant in fields harvested in September than in those harvested in October. Disking during November and February greatly reduced the density of volunteer peanut and winter annual weeds but did not measurably decrease abundance of brachypterous tobacco thrips. Carbofuran application reduced abundance of brachypterous adults and thrips larvae on volunteer peanut by 85–100% during the early spring. Post-harvest tillage and carbofuran application did not measurably reduce incidence of tomato spotted wilt virus in the subsequent peanut crop. Implications for winter ecology and management of spotted wilt are discussed.

Our goal was to investigate in more detail wild and cultivated common bean (Phaseolus vulgaris) accessions from northwestern South America (Colombia, Ecuador, and northern Peru) because prior research had shown this region to be the meeting place of the two major gene pools (Middle American and Andean) of common bean. Explorations were conducted in these countries to collect additional materials not represented in germplasm collections. It was possible to identify wild common bean populations in Ecuador and northern Peru, where they had never been described before. In addition, we were able to extend the distribution of wild common bean in Colombia beyond what was known prior to this study. In all areas, the wild common bean habitat had suffered severely from destruction of natural vegetation. In Colombia, wild common beans were found on the Eastern slope of the Andes (in continuation of its distribution in Venezuela), whereas in Ecuador and northern Peru they were found on the western slope of this mountain range. This geographic distribution was correlated with an ecological distribution in relatively dry environments with intermediate temperatures (known as “dry mountain forest”). Isozyme andphaseolin seed protein analyses of the northern Peruvian and Ecuadoran wild populations showed that they were intermediate between the Middle American and Andean gene pools of the species. Phaseolin analyses conducted on landraces of the Upper Magdalena Valley in Colombia showed that Andean domesticates were grown at a higher altitude than Middle American domesticates suggesting that the former are adapted to cooler temperatures. Our observations and results have the following consequences for the understanding and conservation of genetic diversity in common bean and other crops: 1) Our understanding of the distribution of the wild relative of common bean (and other crops) is imperfect and further explorations are needed to more precisely identify and rescue wild ancestral populations; 2) For crops for which the wild ancestor has not yet been identified, it may be worthwhile to conduct additional explorations in conjunction with genetic diversity studies at the molecular level to guide the explorations; 3) Our study shows the benefit for more efficient germplasm conservation which can be derived from the dynamic interplay between field explorations (and other conservation operations) and molecular analyses to determine genetic distances and diversities; 4) The intermediate materials identified in northern Peru and Ecuador may have basic importance to understand the origin of the common bean and an applied role as a bridge between the Middle American and Andean gene pools; and 5) The differential adaptation to temperature of the two major cultivated gene pools may help breeders select genotypes based at least partially on their evolutionary origin.

The spleen is a critical organ in defence against haemoparasitic diseases like babesiosis. Many in vitro and ex vivo studies have identified splenic cells working in concert to activate mechanisms required for successful resolution of infection. The techniques used in those studies, however, remove cells from the anatomical context in which cell interaction and trafficking take place. In this study, an immunohistological approach was used to monitor the splenic distribution of defined cells during the acute response of naïve calves to Babesia bovis infection. Splenomegaly was characterized by disproportionate hyperplasia of large versus small leucocytes and altered distribution of several cell types thought to be important in mounting an effective immune response. In particular, the results suggest that the initial crosstalk between NK cells and immature dendritic cells occurs within the marginal zone and that immature dendritic cells are first redirected to encounter pathogens as they enter the spleen and then mature as they process antigen and migrate to T-cell-rich areas. The results of this study are remarkably similar to those observed in a mouse model of malarial infection, suggesting these dynamic events may be central to the acute response of naïve animals to haemoparasitic infection.

From 2007-2009, we studied the current (2006) and historic (1892, mid-1950s) extent, current age distribution, and plant species composition of plains cottonwood (Populus deltoides) and non-cottonwood riparian stands along eight study segments of the Missouri River between Fort Benton, Montana and Kansas City Missouri, covering 930 river miles (1500 km) or over 1/3 of the river's length. These segments included all of the unchannelized and unimpounded segments below Fort Benton, as well as portions of two impounded and one channelized segment. Based on GIS analyses of historic maps and aerial photography, the combined area of forests, woodlands, and shrublands in the historic floodplain declined 47% across all study segments from 1892 to 2006, with losses linked to clearing for human land uses (primarily agricultural cropland) or inundation by reservoirs. Most forest loss occurred between 1892 and the 1950s, while most shrubland loss has occurred from the 1950s to 2006. As of 2006, we estimate that a total of 75,600 hectares (186,900 acres) of shrubland, woodland, and forest occurred within the mapped area of the eight study segments, with 66,800 hectares (165,000 acres) or 88% of the total, composed of patch types which contain cottonwood as a significant component. Most (62%) of the cottonwood area is composed of stands 50 years old, and only 14% is from stands that have recruited in the last 25 years. These patterns, along with significant historic declines in shrubland and sandbar area on most segments, indicate that the fluvial geomorphic dynamics that drive cottonwood recruitment have been reduced, and cottonwood regeneration compromised, under the river management practices of at least the last 25-30 years. A significant proportion (24%) of forest in the 25-50 year age class, however, suggested that a temporary pulse in recruitment accompanied geomorphic adjustments in the channel during the first 2-3 decades after dam closure on some segments.

Transcription in the human immunodeficiency virus type 1 (HIV-1) retrovirus is regulated by binding the viral Tat protein (trans-acting transcriptional activator) to the trans-activation response (TAR) RNA sequence. Here, vacuum UV circular dichroism (VUV-CD) is used to study the structure of TAR and its complex with two peptide fragments that are important for Tat binding to TAR. The VUV-CD spectrum of TAR is typical of A-form RNA and is minimally perturbed when bound to either the short or the long Tat peptide. The CD spectra of the complexes indicate an extended structure in the arginine-rich region of Tat from amino acid residue 47 through residue 58 and a short alpha-helix within the adjacent 59-72 region. Models of TAR and its peptide complexes are constructed to integrate these spectroscopic results with current biochemical data. The model suggests that (i) the arginine-rich 49-58 region is primarily responsible for electrostatic interactions with the phosphates of the RNA, (ii) the arginine side chains can additionally interact with substituent groups of the nucleotide bases to confer base recognition in the complex, (iii) the recognition of uracil-23 in TAR is facilitated by the peptide backbone, and (iv) the glutamine-rich face of an alpha-helix within the 59-72 region pairs to bases UGG at nucleotide positions 31-33 in the TAR loop and thus provides an additional motif in the Tat trans-activating protein to recognize TAR RNA.

CD spectra have been measured as a function of temperature for a number of ApA analogues with modified backbones. Oligonucleotides with these modified backbones are being used as antisense agents having potential as viral therapeutics. Results of these studies show that when a carbonyl is substituted for the phosphate to produce an uncharged backbone, the analogues that have either sugar or morpholino substitution do not stack. In contrast, when a morpholino group is substituted for the sugar and the phosphate is modified so as to be uncharged, there is strong base stacking. Stacking interactions in the phosphorus-linked morpholino analogues are at least as strong as those found in d(ApA). The stacking interactions in ApA are weak by comparison. Singular value decomposition demonstrates that the stacking is two state, and Taylor series decomposition yields a coefficient that measures base stacking interactions. The van't Hoff equation is applied to the base stacking coefficient from the Taylor series fitting to give thermodynamic parameters.

To evaluate the association of physical activity with left ventricular structure and function in the general population in a community setting.Cross-sectional study.The Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of subclinical atherosclerosis.A multiethnic sample of 4992 participants (aged 45-84 years; 52% female) free of clinically apparent cardiovascular disease.Physical activity induces beneficial physiological cardiac remodelling in a cross-sectional study of non-athlete individuals.Left ventricular mass, volumes and function were assessed by cardiac magnetic resonance imaging. Physical activity, defined as intentional exercise and total moderate and vigorous physical activity, was assessed by a standard semiquantitative questionnaire.Left ventricular mass and end-diastolic volume were positively associated with physical activity (eg, 1.4 g/m(2) (women) and 3.1 g/m(2) (men) greater left ventricular mass in the highest category of intentional exercise compared with individuals reporting no intentional exercise; p = 0.05 and p0.001, respectively). Relationships were non-linear, with stronger positive associations at lower levels of physical activity (test for non-linearity; p = 0.02 and p = 0.03, respectively). Cardiac output and ejection fraction were unchanged with increased physical activity levels. Resting heart rate was lower in women and men with higher physical activity levels (eg, -2.6 beats/minute lower resting heart rate in the highest category of intentional exercise compared with individuals reporting no intentional exercise; p0.001).In a community-based population free of clinically apparent cardiovascular disease, higher physical activity levels were associated with proportionally greater left ventricular mass and end-diastolic volume and lower resting heart rate.

A case of primary cutaneous hyalohyphomycosis in a healthy individual is presented. The initial clinical impression was keratoacanthoma or squamous cell carcinoma. Upon excision, the lesion proved to be an example of cutaneous hyalohyphomycosis due to an unidentified, non-pigmented fungal organism. The lesion was completely excised, and the patient was treated with saturated solution of potassium iodide. To date, there has been no evidence of recurrence. The clinical, histologic and mycologic aspects of hyalophyphomycosis are discussed.

Studies on the efficacy and economic analysis of Texas panicum management systems in corn were conducted in Georgia on a loamy sand soil in 1987, 1988, and 1989. Management systems that included butylate, EPTC, atrazine plus tridiphane, atrazine plus pendimethalin, atrazine plus trifluralin, paraquat, or ametryn acceptably control Texas panicum. Corn yields were not affected significantly by the Texas panicum management systems. Overall net returns calculated for corn production indicated that systems which included postemergence applications of atrazine, pendimethalin, trifluralin, paraquat, ametryn, or cultivation alone gave the highest net returns. Systems which included butylate, EPTC, or tridiphane frequently had significantly lower net returns.