Sites In Arkansas Research Articles

Impact of PM2.5 filter extraction solvent on oxidative potential and chemical analysis

ABSTRACT Fine particulate matter (PM2.5) is hypothesized to induce oxidative stress, and has been linked to acute and chronic adverse health effects. To better understand the risks and underlying mechanisms following exposure, PM2.5 is collected onto filters but prior to toxicological analysis, particles must be removed from filters. There is no standard method for filter extraction, which creates the possibility that the methods of extraction selected can alter the chemical composition and ultimately the biological implications. In this study, comparisons were made between extraction solvents (methanol (MeOH), dichloromethane (DCM), 0.9% saline, and Milli-Q water) and the results of oxidative potential and elemental concentration analysis of PM2.5 collected across sites in Arkansas, USA. Significant differences were observed between solvents, with DCM having significantly different results compared to all other extraction solvents (p ≤ 0.001). Significant correlations between element, black carbon, and PM2.5 concentrations and oxidative potential were observed. The observed correlations were extraction solvent dependent. For example, in saline extracted samples, oxidative potential had significant negative correlations with: Ba, Cd, Ce, Co, Ga, Mn and significant positive correlations with: Cr, Ni, Th, U. While in MeOH extracted samples, significant positive correlations were only between oxidative potential and Ga, U and significant negative correlations with V. This indicates that PM2.5 samples extracted with different solvents will yield different conclusions about the causal components. This study highlights the importance of filter extraction methods in interpretation of oxidative potential results and comparisons between studies. Implications While there is no standard method for PM2.5 filter extraction, variation of extraction methods impact analytical results. This project identifies that extraction method variation, particularly extraction solvent selection, leads to discrepancies in chemical and toxicological analysis for PM2.5 collected on the same filter. This work highlights the need for methods standardization to support accurate comparisons between PM2.5 research studies, thus providing better understanding of PM2.5 across the globe.

Registration of Arkot 1202, Arkot 1207, Arkot 1208, and Arkot 1214 cotton germplasm lines

AbstractArkot 1202 (Reg. no. GP‐1143, PI 702793), Arkot 1207 (Reg. no. GP‐1144, PI 702794), Arkot 1208 (Reg. no. GP‐1145, PI 702795), and ‘Arkot 1214’ (Reg. no. GP‐1146, PI 702796) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in June 2023. Arkot 1202, Arkot 1207, and Arkot 1208 lines share ‘UA48’ (PVP 201100041) as a common parent. The second parent for Arkot 1202 and Arkot 1207 was MD25‐87Y and ‘Columbia’, respectively. The second parent for Arkot 1208 was the F1 of a double cross of F1 (Ark 0219‐15 crossed with LA063071653) and F1 (Arkot 0222 crossed with Ark 0203‐11). Arkot 1214 was derived from a four‐way cross of two double crosses: F1 (MD25‐26ne crossed with Arkot 0113) and F1 (Arkot 0114 crossed with ‘UA222’). In replicated field tests at four Arkansas sites over 5 years, the four lines produced more lint yield than UA48 and UA222. Wide adaptation of the lines was indicated by high lint yields of lines in 2020 regional tests. All four lines displayed high resistance to bacterial blight and Fusarium wilt race 1. Plant (leaf, stem, and bract) trichomes and tarnished plant bug response of Arkot 1202 and Arkot 1214 were equal to UA48, but Arkot 1207 and Arkot 1208 were equal to UA222. Yield component values of the four lines were equal to or better than UA222. The maturity and fiber quality of Arkot 1202 approached that of UA48 while the other three were similar to UA222.

Registration of Arkot 1102ne cotton germplasm line

AbstractArkot 1102ne (Reg. no. GP‐1142; PI 702558) is a conventional, nectariless cotton (Gossypium hirsutum L.) germplasm line released by the Arkansas Agricultural Experiment Station in October 2022. The germplasm line represents an ongoing effort to develop improved genotypes with enhanced yield, yield components, seed traits, earliness, host plant resistance, and fiber properties. Arkot 1102ne was compared to ‘UA48’ and ‘UA222’ over 5 years and four test sites in Arkansas. Across all the test sites, lint yields of Arkot 1102ne were 7.9% and 20.8% higher than those of UA222 and UA48, respectively, due to its higher lint percentage, seed per area, and fiber density. Arkot 1102ne produced the highest average yield of 21 genotypes over 10 locations in the 2019 Regional Breeders’ Network Test (RBTN). Arkot 1102ne produced the highest oil and protein percentages at four 2019 RBTN locations where seed were evaluated. Host plant resistance traits that have been measured on Arkot 1102ne include bacterial blight resistance and Verticillium wilt tolerance. Leaf pubescence and bract trichome density of Arkot 1102ne were intermediate between UA48 and UA222, but stem pubescence was lower. This combination of host plant resistance and yield components should lead to more stable yield production over contrasting environments. The fiber quality of Arkot 1102ne was lower than UA48 and was similar to that of UA222.

Registration of Arkot 1112, Arkot 1114, and Arkot 1115 cotton germplasm lines

AbstractArkot 1112 (Reg. no. GP‐1139, PI 702559), Arkot 1114 (Reg. no. GP‐1140, PI 702560), and Arkot 1115 (Reg. no. GP‐1141, PI 702561) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in November, 2022. The three lines share Arkot 0306 (PI 671966) as a common parent. The second parents for Arkot 1112, Arkot 1114, and Arkot 1115 were ‘UA222’ (US patent no. 8,859,862), Arkot 0309 (PI 669969), and Arkot 0316 (PI 669970), respectively. The three lines were compared with ‘UA48’ and UA222 in replicated field tests at four Arkansas sites over 5 years. Over these tests, each of the three lines produced about 11 and 25% higher lint yields than UA48 and UA222, respectively. Lint yields of Arkot 1115 exceeded those of Arkot 1112 and Arkot 1114. Over 10 locations of the 2019 Regional Breeders Testing Network test, lint yields of Arkot 1112, Arkot 1114, and Arkot 1115 were equal to each other and ranked third, fourth, and fifth, respectively, out of 22 genotypes, indicating that the lines have wide adaptation. Leaf pubescence, stem pubescence, and bract trichome density of the lines were higher than UA48 and similar to UA222. All three lines displayed high resistance to bacterial blight. The lines were more resistant to tarnished plant bug than UA48 but were more susceptible to tarnished plant bug than UA222. Fiber quality of Arkot 1115 approached that of UA48 (excellent fiber quality), whereas Arkot 1112 and Arkot 1114 was similar to UA222 (good fiber quality).

Registration of Arkot 0902 cotton germplasm line

AbstractArkot 0902 (Reg. no. GP‐1130, PI 700940) is a conventional cotton (Gossypium hirsutum L.) germplasm line released by the Arkansas Agricultural Experiment Station in May 2022. Arkot 0902 was derived from a cross of ‘GA 230’ (PVP 201500309) and Arkot 0012. Over 5 yr and four test sites in Arkansas, Arkot 0902 produced 10 and 20% higher lint yields than ‘UA222’ and ‘UA48’, respectively. The high lint yield of Arkot 0902 was attributed to producing more (and smaller) seed per area than UA222 or UA48. Arkot 0902 possesses leaf and stem pubescence similar to UA48 (smooth leaf) but has higher density of marginal bract trichomes. Arkot 0902 displayed high resistance to bacterial blight and was similar to UA222 and UA48 in their response to other diseases. Arkot 0902 was more resistant to tarnished plant bug than UA48 and equal to UA222. Most fiber quality traits of Arkot 0902 approached those of UA48, a high fiber–quality cultivar.

Registration of Arkot 1005, Arkot 1015, and Arkot 1019 cotton germplasm lines

AbstractArkot 1005 (Reg. no. GP‐1127, PI 700852), Arkot 1015 (Reg. no. GP‐1128, PI 700853), and Arkot 1019 (Reg. no. GP‐1129, PI 700854) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in April 2022. The lines were compared with UA48 and UA222 (check cultivars) in replicated field tests at four Arkansas sites over 5 yr. Over these tests, lint yields of the three lines did not differ from each other and were greater than UA48. Lint yield of Arkot 1015 was greater than UA222, while lint yields of Arkot 1005 and Arkot 1019 were equal to UA222. Performance in regional tests indicates that the lines have wide adaptation. The lint yields of Arkot 1015 and Arkot 1019 were attributed to producing more (and smaller) seed per area and less lint per seed (lint index) than UA222. Arkot 1005 produced higher lint index than the other two lines and the two check cultivars. Seed per area for Arkot 1005 was higher than UA48, equal to UA222, and lower than Arkot 1015 and Arkot 1019. Leaf pubescence, stem pubescence, and bract trichome density of the three lines were intermediate between UA222 and UA48. All three lines displayed high resistance to bacterial blight and were similar to UA222 and UA48 in their response to other diseases. Arkot 1015 was more resistant to tarnished plant bug (TPB) than Arkot 1005, Arkot 1019, and UA48, but all were more susceptible to TPB than UA222. Compared with the other lines and check cultivars, Arkot 1005 and Arkot 1019 displayed higher and lower, respectively, resistance to seed deterioration. Fiber quality of Arkot 1019 was superior to UA48, UA222, and the other lines. Fiber quality of Arkot 1005 and Arkot 1015 was superior to UA222.

Benzobicyclon for weedy rice control in quizalofop- and imidazolinone-resistant rice systems

AbstractGowan Company recently registered benzobicyclon, a WSSA Group 27 herbicide, as a postflood option in rice. It is the first 4-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide commercially available in mid-southern U.S. rice production. In 2018 and 2019, field experiments were conducted across multiple sites in Arkansas to determine if the addition of benzobicyclon to quizalofop- or imidazolinone-resistant rice herbicide programs would improve weedy rice control. Across site-years, one application of quizalofop, either at the 1- or 3-leaf rice stage, followed by benzobicyclon applied postflood, provided comparable weedy rice control to two sequential applications of quizalofop, which is a standard herbicide program in quizalofop-resistant rice. Additionally, treatments containing quizalofop or quizalofop followed by benzobicyclon injured rice ≤5% at 28 d after the postflood application. Across site-years, at 28 d after the postflood application of benzobicyclon, all treatments containing a full-season herbicide program followed by benzobicyclon postflood provided comparable or improved weedy rice control when compared to two sequential early postemergence applications of imazethapyr. In both experiments, rice treated with benzobicyclon yielded comparably or better than treatments containing the standard herbicide program for each system. Findings from this research suggest that the use of benzobicyclon in quizalofop- and imidazolinone-resistant rice systems could be an additional and viable weedy rice control option for rice producers.

Registration of two Arkot 0912 sister cotton germplasm lines

AbstractArkot 0912‐18 (Reg. no. GP‐1098, PI 697032) and Arkot 0912‐41 (Reg. no. GP‐1097, PI 697031) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in December 2020. Both lines were derived from crossing ‘UA48’ and ‘UA222’. They produced higher lint yields than their parents over 5 yr and at four test sites in Arkansas. Both produced similar lint yields at each test site. Over test sites, the lines produced about 13 and 24% higher lint yields than UA222 and UA48, respectively. Arkot 0912‐18 produced the highest lint yield of all entries evaluated in the 2017 Regional Breeders Network Test. Over all locations of the 2017 Regional High Quality Test, lint yields of Arkot 0912‐41 ranked fourth out of 20 genotypes (second‐highest of 11 conventional genotypes) and equaled the lint yields of DP 1646 B2XF (U.S. patent no. 9,961,845) and PHY 444 WRF. Both lines produced higher lint percentage and lint index and were taller than either parent. Leaf pubescence, stem pubescence, and bract trichome density of each line exceeded both parents. Visual ratings of Verticillium wilt for Arkot 0912‐18 exceeded those of UA48. Both lines displayed high resistance to bacterial blight and were similar to UA222 and UA48 in their response to other diseases. The lines were more resistant to tarnished plant bug than UA48 but were more susceptible to tarnished plant bugs than UA222. Measurements of fiber quality for the two lines were intermediate between that of UA48 (excellent fiber quality) and UA222 (good fiber quality).

The Role of Acoustics in the Conservation of the Ivory-Billed Woodpecker (Campephilus principalis)

The Ivory-billed Woodpecker (Campephilus principalis) is an iconic species that has survived in barely detectable numbers for the past 100 years, during which it has been feared extinct only to be rediscovered several times. The most recent rediscovery was announced in an article that was featured on the cover of Science in 2005. The persistence of the Ivory-billed Woodpecker became controversial when ornithologists were unable to obtain a clear photo for documenting this ultra-elusive bird during multi-year searches at sites in Arkansas and Florida, where they had several sightings and were convinced these birds were present. Audio recordings of ‘kent’ calls and double knocks were obtained at both sites, but such recordings are not regarded as conclusive evidence of persistence. A debate on this issue that took place in Science and Nature focused on relatively weak video evidence obtained in Arkansas but excluded three videos obtained in Louisiana and Florida that show flights, field marks, and other behaviors and characteristics that are consistent with the Ivory-billed Woodpecker but no other species of the region. Kent calls were recorded in the 1930s, when other types of vocalizations were observed but not recorded, including a high-pitched alarm call. On two occasions in Louisiana, high-pitched calls were observed coming from the direction of an alarmed Ivory-billed Woodpecker, and several of them were recorded. The spectrograms of the high-pitched calls and all other known and putative vocalizations of the Ivory-billed Woodpecker consist of simultaneously excited harmonics. A harmonic oscillator model has been used to draw a connection between the drumming that is typical of most woodpeckers and the double knocks of the Ivory-billed Woodpecker and other Campephilus woodpeckers. Drumming corresponds to periodic forcing; double knocks correspond to impulsive forcing, and a single thrust of the body is sufficient to produce two impacts of the bill in rapid succession. The audio recordings from Arkansas and Florida were obtained with single microphones. A horizontal array of microphones would make it possible to detect weaker sounds and determine the directions of sources. This approach has the potential to lead to the discovery of a nest, and it might be more effective if the array is placed above the treetops, where sounds might propagate to longer ranges.

Registration of three Arkot 0908 cotton germplasm lines

AbstractArkot 0908‐52 (Reg. no. GP‐1091, PI 697035), Arkot 0908‐56 (Reg. no. GP‐1090, PI 697034), and Arkot 0908‐60 (Reg. no. GP‐1089, PI 697033) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in October 2020. The lines are high performing, early maturing germplasm derived from parents (‘GA 230’ and ‘UA222’) having contrasting backgrounds and maturity. The lines produced higher lint yields than UA222 and ‘UA48’ over 5 yr and at four test sites in Arkansas, producing similar relative lint yields across all test sites and about 15 and 25% higher than lint yields of UA222 and UA48, respectively. Additionally, they had smaller seed while producing more seed per area and more or equal amount of lint per seed than UA222 or UA48. Arkot 0908‐52 and Arkot 0908‐60 performed well in the 2017 Regional High Quality Test and the 2017 Regional Breeders Network Test, respectively. Leaf pubescence and bract trichome density of Arkot 0908‐56 were greater than Arkot 0908‐52, Arkot 0908‐60, and UA48. Stem pubescence density of Arkot 0908‐52 and Arkot 0908‐56 was similar to UA48 and UA222 but greater than Arkot 0908‐60. All three lines displayed high resistance to bacterial blight and were similar to UA222 and UA48 in their response to other diseases. Arkot 0908‐56 and Arkot 0908‐60 were more resistant to tarnished plant bug than Arkot 0908‐52 and UA48, but all were more susceptible to tarnished plant bug than UA222. Fiber quality of Arkot 0908‐52 and Arkot 0908‐56 was similar to UA48, while fiber quality of Arkot 0908‐60 was similar to UA222.

Chemically Precipitated Struvite Dissolution Dynamics over Time in Various Soil Textures

Phosphorus (P) is a fundamental nutrient in agricultural production and is one of three major components in common fertilizers. The majority of fertilizer-P sources are derived from phosphorus rock (PR), which has finite abundance; thus a sustainable source of P is imperative for future agricultural productivity. A potential sustainable P source may be the recovery of the mineral struvite (MgNH4PO4·6H2O) from wastewater treatment plant effluent, but struvite behavior in soils of varying texture is not well characterized. The objective of this study was to assess the dissolution dynamics of a commercially available, wastewater-recovered struvite product over time in a plant-less, moist-soil incubation experiment with multiple soil textures. Chemically precipitated struvite (Crystal Green; CG) from municipal wastewater in pelletized and finely ground forms were added to soil cups at a rate of 24.5 kg∙P∙ha−1 containing soils of varying texture (i.e. loam, silty clay loam, and two different silt loams) from agricultural field sites in Arkansas. Soil cups were destructively sampled five times over a 6-month period to examine the change in water-soluble (WS) and weak-acid-extractable (WAE) P, K, Ca, Mg, and Fe concentrations from their initial concentration. After 0.5 months, both WS-P and WAE-P concentrations increased (P ∙kg−1, respectively, than in the pelletized CG treatment, which averaged 14.0 and 12.2 mg∙kg−1, respectively, across all soils. Over the course of the 6-month incubation, WS- and WAE-P concentrations generally increased over time in the pelletized and decreased over time in the finely ground treatment, confirming the slow-release property of pelletized CG that has been previously reported. The results of this study provide valuable insight regarding struvite-P behavior in various soils and provide further supporting evidence for the utilization of struvite as a potential alternative, sustainable fertilizer-P source.

Current Research: Update on the Hodges Collection of Native American Artifacts

During the 1930s and 1940s, Thomas and Charlotte Hodges of Bismarck, Arkansas, surface collected and excavated artifacts from archaeological sites in Arkansas. Most came from ancestral Caddo sites in the Middle Ouachita River valley in Clark and Hot Spring counties, with a small portion originating from Southeast Arkansas sites. The Hodgeses, along with Vere Huddleston and Robert Proctor of Arkadelphia, were amateur archeologists at a time when there were few professional archeologists working in the state. Philip Phillips of Harvard University photographed some of the Hodges and Huddleston collections during his 1939 Ouachita River Valley survey, and Alex Krieger from the University of Texas photographed artifacts from the Hodges, Huddleston, and Proctor collections, using some to illustrate a typology of Caddo pottery that we still employ today.

Report: Abstracts from the 2018 Caddo Conference in Idabel, Oklahoma

The 2018 Caddo Conference was held March 8-10, 2018 at the Museum of the Red River in Idabel, Oklahoma. Fifty attendees registered for the conference. The conference began with a reception at the museum on Thursday evening. On Friday, the program included eight papers and presentations covering archaeological work in Texas and Oklahoma and a longer presentation on the rebuilding of the Caddo house at Caddo Mounds State Park in Texas. A poster session was also held on Friday afternoon. Conference attendees were given a tour of the collections housed at the museum, which include a large collection of Caddo vessels and objects from all over the world. Friday ended with dances by the Metro Oklahoma City (OKC) Caddo Culture Club, beginning with the Turkey Dance and a delicious barbecue dinner held at the museum. On Saturday, the eight presentations covered sites in Arkansas and Oklahoma, Spiro iconography, and included a presentation on the Spiro exhibit forthcoming at the Cowboy and Western Heritage Museum in Oklahoma City. Just before breaking for lunch on Saturday, Caddo Culture Club and Metro OKC Caddo Culture Club members led a song using the large drum on exhibit in the museum.

Registration of Arkot 0611, Arkot 0617, and Arkot 0712 Cotton Germplasm Lines

Arkot 0611 (Reg. No. GP‐1035, PI 687864), Arkot 0617 (Reg. No. GP‐1037, PI 687866), and Arkot 0712 (Reg. No. GP‐1036, PI 687865) are conventional germplasm lines of cotton (Gossypium hirsutum L.) released by the Arkansas Agricultural Experiment Station (AAES) in April 2018. The lines were released as part of an ongoing effort to develop improved genotypes with enhanced yield, yield components, earliness, host plant resistance, and fiber properties. They share one common parent, DX25105N, a privately developed line made available to AAES by a Memorandum of Agreement. All three lines produced equal or higher lint yields than ‘DP 393’ and ‘UA48’ over 4 yr and at four test sites in Arkansas. Over all test sites, Arkot 0611 produced 10 and 22% higher lint yields than DP 393 and UA48, respectively. Both Arkot 0617 and Arkot 0712 produced 12% more lint than UA48. Lint percentage, seed per hectare, fibers per seed, and fiber density of each line were greater than UA48 and equal to or greater than DP 393. Compared with the check cultivars, all three lines were earlier maturing, but Arkot 0611 and Arkot 0617 tended to have taller plants. All three lines produced more dense leaf pubescence and bract trichomes than either check cultivar. Fiber quality of Arkot 0611 was inferior to either check, and fiber quality of Arkot 0617 and Arkot 0712 was higher than DP 393 but lower than UA48. The DX250105N parent of these lines increases the genetic diversity with the AAES cotton breeding program and broadens the available cotton germplasm pool.

Registration of Arkot 0705 and Arkot 0711 Cotton Germplasm Lines

Arkot 0705 (Reg. No. GP‐1033, PI 685636) and Arkot 0711 (Reg. No. GP‐1034, PI 685637) are conventional germplasm lines of cotton (Gossypium hirsutum L.) released by the Arkansas Agricultural Experiment Station in April 2017. The lines were released as part of an ongoing effort to develop improved genotypes having enhanced yield, yield components, earliness, host plant resistance, and fiber properties. Both Arkot 0705 and Arkot 0711 produced equal or higher lint yields than ‘DP 393’ and ‘UA48’ over 4 yr and at four test sites in Arkansas. Over all test sites, Arkot 0705 and Arkot 0711 produced 10.7 and 12.0%, respectively, higher lint yields than DP 393, and both produced over 20% more lint than UA48. Arkot 0705 has less dense stem pubescence and bract trichomes, higher lint percentage, higher lint index, and more fibers per seed than DP 393. Arkot 0711 differs from DP 393 having more dense leaf pubescence, less dense stem pubescence, lower bract trichome density, being earlier maturing, and having higher lint percentage, lint index, fibers per seed, and fiber density. Both lines displayed high resistance to bacterial blight and were similar to DP 393 in their response to other diseases and tarnished plant bugs. Fiber quality of the two lines was slightly lower than DP 393 and considerably lower than UA48.

Natal Philopatry and Juvenile Survival in Swainson's Warblers (Limnothlypis swainsonii)

ABSTRACT.— Understanding natal dispersal and rates of philopatry can help provide minimum estimates of juvenile survival, a vital demographic parameter for which little information is available. However, despite the large number of hatch-year migratory birds banded every year at their natal sites, few are resighted or recaptured. Here, we report on the return of 22 Swainson's Warblers (Limnothlypis swainsonii) banded as nestlings or fledglings between 1997–2008 at breeding sites in Arkansas, North Carolina, and South Carolina, USA. Of 284 nestling Swainson's Warblers banded, we found 13 (4.6%) exhibiting natal philopatry. Of 95 fledglings banded, we detected 9 (9.5%) in later years. The median distance moved from the original capture to an encounter location the subsequent breeding season for all second-year birds we detected was 1.5 km (range = 54 m to 15.4 km). The mark-recapture estimate for first-year apparent survival was 0.119 (SE = 0.032). Estimated recapture probability was between 0.55 and 0.65. ...

Evaluation of the TBET Model for Potential Improvement of Southern P Indices.

Due to a shortage of available phosphorus (P)-loss datasets, simulated data from an accurate quantitative P transport model could be used to evaluate a P Index. The objective of this study was to compare predictions from the Texas Best Management Practice Evaluation Tool (TBET) against measured P-loss data to determine whether the model could be used to improve P Indices in the southern region. Measured P-loss data from field-scale study sites in Arkansas, Georgia, and North Carolina were used to assess the accuracy of TBET for predicting field-scale loss of P. We found that event-based predictions using an uncalibrated model were generally poor. Calibration improved runoff predictions and produced scatterplot regression lines that had slopes near one and intercepts near zero. However, TBET predictions of runoff met the performance criteria (Nash-Sutcliffe efficiency ≥ 0.3, percent bias ≤ 35%, and mean absolute error ≤ 10 mm) in only one out of six comparisons: North Carolina during calibration. Sediment predictions were imprecise, and dissolved P predictions underestimated measured losses. In North Carolina, total P-loss predictions were reasonably accurate because TBET did a slightly better job of predicting sediment losses from cultivated land. In Arkansas and Georgia, where the experimental sites were in forage production, the underprediction of dissolved P led directly to the underpredictions of total P. We conclude that TBET cannot be used to improve southern P Indices, but a curve number approach could be incorporated into P Indices to improve runoff predictions.

Caddo Ceramic Vessel Database from Sites in Texas, Louisiana, Oklahoma, and Arkansas

This compilation of more than 9310 ancestral Caddo ceramic vessels is from 356 sites and collections primarily in Texas (i.e., about 87 percent of the vessels and 88 percent of the sites and collections), although there are significant collections in this compilation from sites in Arkansas, Louisiana, and Oklahoma. The ceramic vessel database has been compiled from available published and unpublished articles, monographs, and technical reports, as well as ceramic vessel inventory forms (when available) on file at the Texas Archeological Research Laboratory.

Registration of Arkot 0502ne, Arkot 0504ne, Arkot 0506ne, and Arkot 0517HG Germplasm Lines of Cotton

Upland cotton (Gossypium hirsutum L.) production may be enhanced by incorporating host plant resistance traits into improved lines. Arkansas Agricultural Experiment Station has released four germplasm lines of upland cotton, designated as Arkot 0502ne (Reg. No. GP‐1007, PI 677330), Arkot 0504ne (Reg. No. GP‐1008, PI 677331), Arkot 0506ne (Reg. No. GP‐1009, PI 677332), and Arkot 0517HG (Reg. No. GP‐1010, PI 667333), which were bred to improve the efficiency of yield production. Arkot 0502ne, Arkot 0504ne, and Arkot 0506ne are nectariless lines that were derived from crossing Arkot 9608ne with JAJO 1145ne, Arkot 9314, and Arkot 9513, respectively. Arkot 0517HG, derived from a cross of Arkot 9304b with Arkot 9513, possesses the high‐glanding trait. The nectariless trait infers some resistance to tarnished plant bugs, while the high‐glanding trait infers some resistance to lepidopterous insect pests. All four lines were compared to ‘DP 393’ and ‘UA48’ over 5 yr and four test sites in Arkansas. Over all test sites, lint yields of the four lines were equal to DP 393 and exceeded UA48. The lines differed with respect to yield components and other morphological traits. All four lines displayed high resistance to bacterial blight and were equal to or more resistant to Verticillium wilt and tarnished plant bug than check cultivars. Fiber quality scores of all four lines exceeded that of DP 393 but were lower than UA48. All four lines generally displayed high yielding ability, specific host plant resistance traits, early maturity, and acceptable fiber quality.

Larinus minutus (Coleoptera: Curculionidae) and Urophora quadrifasciata (Diptera: Tephritidae), Evidence for Interaction and Impact on Spotted Knapweed in Arkansas.

Interactions among seed-feeding insects are well noted in the literature, with many of these interactions being asymmetrical and causing a disadvantage for one of the species involved. While often effective, the use of the cumulative stress approach to biological control (where multiple natural enemy species are released) may increase the risk of interaction, which may lead to less effective biological control programs. Spotted knapweed (Centaurea stoebe ssp. micranthos (Gugler) Hayek) is an invasive plant that causes damage in rangelands and pastures. In Arkansas, two biological control agents for spotted knapweed, Larinus minutus Gyllenhal and Urophora quadrifasciata Meigen, are established. Both species attack the capitula of spotted and diffuse knapweeds. There is potential for interactions between these species, and this could affect the efficacy of the biological control program. To evaluate these potential interactions, we collected spotted knapweed capitula weekly from three sites in Arkansas from 2010 to 2012. Capitula were monitored for emergence of L. minutus and U. quadrifasciata, and the effect on seed reduction was analyzed. Over all three years, L. minutus and U. quadrifasciata were present in 35.8% (492) and 22.8% (313) of the capitula, respectively. We determined that the occurrences of L. minutus and U. quadrifasciata were not independent of each other, and that L. minutus is more effective at reducing spotted knapweed seed production than U. quadrifasciata within individual capitula. Seed production in capitula with both natural enemies present was no different from capitula with L. minutus.