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At the cellular level, membrane damage is a fundamental cause of yield loss at high temperatures (HT). We report our investigations on a subset of a peanut (Arachis hypogaea) recombinant inbred line population, demonstrating that the membrane lipid remodeling occurring at HT is consistent with homeoviscous adaptation to maintain membrane fluidity. A major alteration in the leaf lipidome at HT was the reduction in the unsaturation levels, primarily through reductions of 18:3 fatty acid chains, of the plastidic and extra-plastidic diacyl membrane lipids. In contrast, levels of 18:3-containing triacylglycerols (TGs) increased at HT, consistent with a role for TGs in sequestering fatty acids when membrane lipids undergo remodeling during plant stress. Polyunsaturated acyl chains from membrane diacyl lipids were also sequestered as sterol esters (SEs). The removal of 18:3 chains from the membrane lipids decreased the availability of susceptible molecules for oxidation, thereby minimizing oxidative damage in membranes. Our results suggest that transferring 18:3 chains from membrane diacyl lipids to TGs and SEs is a key feature of lipid remodeling for HT adaptation in peanut. Finally, QTL-seq allowed the identification of a genomic region associated with heat-adaptive lipid remodeling, which would be useful for identifying molecular markers for heat tolerance. [ABSTRACT FROM AUTHOR]

'TifEagle' bermudagrass [Cynodon dactylon (L.) Pets. x C. transvaalensis Burtt-Davy] is a fine textured hybrid bermudagrass used for golf course putting greens in the subtropical and tropical regions of the world. The growth and performance of TifEagle and other bermudagrass often decline in reduced light environments (RLEs). This study quantified a daily light integral (DLI; mol [m.sup.-2] [d.sup.-1]) required to maintain commercially acceptable TifEagle bermudagrass maintained under golf green conditions. Three levels of shade, none, low, and high (0, 41, and 92%), were applied to mature TifEagle bermudagrass during morning (sunrise to 1100 h) and afternoon (1500 h to sunset) hours, allowing full irradiance from 1100 to 1500 h to mimic a golf green situation where trees or structures are adjacent to, but rarely directly overhead. The study was performed for 8 wk in June to August 2001 and 2002. An average minimal DLI of 32.6 mol [m.sup.-2] [d.sup.-1] was needed to maintain commercially acceptable TifEagle turf quality (TQ ≥ 7). Other plant responses measured included percentage lateral regrowth (RG), total shoot chlorophyll, and total nonstructural carbohydrates (TNC). These responses declined significantly when the DLI ≤ 32.6 mol [m.sup.-2] [d.sup.-1]. Differences in diurnal shade exposure occurred. High afternoon shade reduced TifEagle bermudagrass TQ, percentage lateral RG, shoot chlorophyll, and TNC by 3.0 rating units and 17, 39, and 27%, respectively, compared with no afternoon shade (NSA). High morning shade reduced TQ, percentage lateral RG, and shoot chlorophyll by 1.5 rating units and 11 and 16%, respectively, compared with no morning shade (NSM). Overall, afternoon shade applications were more detrimental to TifEagle bermudagrass growth and performance compared with morning shade., DWARF-TYPE BERMUDAGRASSES such as TifEagle are becoming an increasingly popular choice for golf putting greens in the southern USA. These grasses provide an excellent putting surface when exposed to sufficient [...]

Researchers have used quantitative genetics to map cotton fiber quality and agronomic performance loci, but many alleles may be population or environment-specific, limiting their usefulness in a pedigree selection, inbreeding-based system. Here, we utilized genotypic and phenotypic data on a panel of 80 important historical Upland cotton (Gossypium hirsutum L.) lines to investigate the potential for genomics-based selection within a cotton breeding program's relatively closed gene pool. We performed a genome-wide association study (GWAS) to identify alleles correlated to 20 fiber quality, seed composition, and yield traits and looked for a consistent detection of GWAS hits across 14 individual field trials. We also explored the potential for genomic prediction to capture genotypic variation for these quantitative traits and tested the incorporation of GWAS hits into the prediction model. Overall, we found that genomic selection programs for fiber quality can begin immediately, and the prediction ability for most other traits is lower but commensurate with heritability. Stably detected GWAS hits can improve prediction accuracy, although a significance threshold must be carefully chosen to include a marker as a fixed effect. We place these results in the context of modern public cotton line-breeding and highlight the need for a community-based approach to amass the data and expertise necessary to launch US public-sector cotton breeders into the genomics-based selection era. [ABSTRACT FROM AUTHOR]

Online educational modalities are used extensively in courses that do not require hands-on laboratory experiences. However, due to the COVID-19 pandemic, there has been a need for transition from in-person to online laboratory-based courses, especially in animal and veterinary science courses. This study evaluated 163 undergraduate students enrolled in an introductory animal and veterinary science laboratory in the fall 2020 semester. Using surveys throughout the semester, student responses were collected and evaluated. Results indicated student performance on quizzes and exams were better during online instruction compared with in-person instruction, which contradicted previous studies reported in the literature. As a majority of these students were first-year, first-semester students, their metacognitive abilities were likely not fully developed. This laboratory course was taught initially online for the first half of the semester and then transitioned to inperson instruction as the university public health regulations allowed. Socially shared metacognitive regulation was only exercised during the in-person portion of the class. Results indicate an animal and veterinary science laboratory can successfully be taught online. [ABSTRACT FROM AUTHOR]

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Water retentionx is considered an important characteristic for determining the efficiency and effectiveness of soils and greenhouse substrates. Surfactants have the potential to improve water infiltration and distribution uniformity throughout the soil profile. In addition, efficient irrigation can improve the wettability of soils. The objective of this study was to determine how surfactants and irrigation influence soil water content (SWC), leachate volume, and pH in soils and greenhouse substrates. This study was conducted at Clemson University, SC, on two soils (sandy loam and sand) and two substrates (Fafard 3B-SURF and 80% sand, 20% peat). Four surfactants (a) 10% oleic acid esters of block copolymers (OAC), (b) 30% alkoxylated polyols and 21% glucoethers (APG), (c) 50% nonionic polyols and 5% 1,2-propanediol (NIPP), and (d) water control (CNT) with two irrigation regimes (ONCE and SPLIT) were applied to PVC columns. Based on the leachate results, applying irrigation volume as SPLIT in conjunction with using a surfactant reduced leachate up to 75%. The soils retained more water when OAC and NIPP surfactants were applied. When the soil was left to dry out, the SWC was 5 and 9% higher from SPLIT irrigation compared with ONCE irrigation in the sand-peat and the sand soils, respectively. Surfactants can increase SWC, and combining split irrigation with surfactants can play an important role in reducing leaching from soils and greenhouse substrates, resulting in water quality and quantity conservation, and an economic advantage to the grower. [ABSTRACT FROM AUTHOR]

Significant genotype (G) × environment (E) effects for cotton (Gossypium hirsutum L.) seed quality traits have been identified in previous studies. Significant G × E interactions necessitate multiplelocation tests to evaluate seed quality traits, which add cost to the tests. Reduction of testing locations could trim costs if the analysis of G × E interactions and the efficiency in breeding are not dramatically affected. The objectives of this study were: 1) to determine an appropriate reduction of testing locations without significant loss in power for detecting G × E effects; 2) to determine an appropriate reduction of testing locations without significant loss in accuracy for estimating strain means; and 3) to identify a possible mega-environment for evaluation of seed traits using GGE biplot. Historical data of Regional High Quality (RHQ) tests from 2005 through 2013 were used to address the objectives for three seed quality traits including oil content, N content, and free-gossypol. Significant G × location (L) interactions were detected in most cases. However, with averages of the three traits, less G × L interactions were detected with 7.3% and 9.1% non-significance, when two and three locations were omitted, respectively. Reduction of locations up to three, increased standard error to 25% of those with zero locations omitted. There was no clear mega-environment identified for seed traits. However, the locations of Lubbock, TX, Stoneville, MS, Florence, SC, and Portageville, MO were identified as being more representative than others for evaluation of the N content. [ABSTRACT FROM AUTHOR]

Understanding the relationship between fire intensity and fuel mass is essential information for scientists and forest managers seeking to manage forests using prescribed fires. Peak burning temperature, duration of heating, and area under the temperature profile are fire behavior metrics obtained from thermocouple-datalogger assemblies used to characterize prescribed burns. Despite their recurrent usage in prescribed burn studies, there is no simple protocol established to guide the orientation of thermocouple installation. Our results from dormant and growing season burns in coastal longleaf pine (Pinus palustris Mill.) forests in South Carolina suggest that thermocouples located horizontally at the litter-soil interface record significantly higher estimates of peak burning temperature, duration of heating, and area under the temperature profile than thermocouples extending 28 cm vertically above the litter-soil interface (p < 0.01). Surprisingly, vertical and horizontal estimates of these measures did not show strong correlation with one another (r² ≤ 0.14). The horizontal duration of heating values were greater in growing season burns than in dormant season burns (p < 0.01), but the vertical values did not indicate this difference (p = 0.52). Field measures of fuel mass and depth before and after fire showed promise as significant predictive variables (p ≤ 0.05) for the fire behavior metrics. However, all correlation coefficients were less than or equal to r² = 0.41. Given these findings, we encourage scientists, researchers, and managers to carefully consider thermocouple orientation when investigating fire behavior metrics, as orientation may affect estimates of fire intensity and the distinction of fire treatment effects, particularly in forests with litter-dominated surface fuels. [ABSTRACT FROM AUTHOR]

The O horizon, or detrital layer, of forest soils is linked to long-term forest productivity and health. Fuel reduction techniques, such as prescribed fire, can alter the thickness and composition of this essential ecosystem component. Developing an understanding of the changes in the chemical composition of forest detritus due to prescribed fire is essential for forest managers and stakeholders seeking sustainable, resilient, and productive ecosystems. In this study, we evaluated fuel quantity, fuel structure, and detrital chemical composition in longleaf pine (Pinus palustris Miller) forests that have been frequently burned for the last 40 yr at the Tom Yawkey Wildlife Center in Georgetown, SC. Our results suggest that frequent prescribed fire reduces forest fuel quantity (p < 0.01) and vertical structure (p = 0.01). Using pyrolysis-gas chromatography/mass spectrometry as a molecular technique to analyze detrital chemical composition, including aromatic compounds and polycyclic aromatic hydrocarbons, we found that the chemical composition of forest detritus was nearly uniform for both unburned and burned detritus. Our burning activities varied in the short term, consisting of annual dormant, annual growing, and biennial dormant season burns. Seasonal distinctions were present for fuel quantity and vertical fuel structure, but these differences were not noted for the benzene/phenol ratio. These results are significant as more managers consider burning existing longleaf stands while determining effective management practices for longleaf stands yet to be established. Managers of such stands can be confident that frequent, low-intensity, low-severity prescribed burns in longleaf pine forests do little to affect the long-term chemical composition of forest detritus. [ABSTRACT FROM AUTHOR]

Family forest owners (FFOs) control a majority of private forestland in the United States and have widely diverse ownership and management objectives. Many FFOs manage their holdings for timber production and, thus, are concerned with issues such as reforestation incentives and tax treatment of timber revenues. Their actual knowledge of the tax aspects of timber management varies, with some owners even unaware of the federal income tax provisions that apply to timber. This research used econometric techniques to establish socioeconomic predictors of FFO awareness and use of federal income tax provisions. Socioeconomic factors (such as size of forest holding, ownership objective, education, age, and income) were evaluated in terms of association with awareness and use of income tax provisions. Data were obtained from a survey of 1350 South Carolina FFOs (472 useable responses). A two-step sample selection methodology revealed that membership in a landowner organization and size of forest holding positively influence landowner awareness of the seven tax provisions, while ownership objective and level of education exhibited varying degrees of influence. Overall, the findings suggest that size of forest holding is the key determinant that influences landowner use of the provisions. These tax incentives are one of the foundations of federal policies encouraging active forest management by FFOs and the effectiveness of the various incentives has crucial implications for forest policy analysis. [ABSTRACT FROM AUTHOR]

A restoration project was initiated in 2007 to convert a forested section of Crowders Mountain State Park in North Carolina to a prairie ecosystem using primarily local seed material. All vascular species were identified curing 4 growing seasons (2008-2011) and species richness, diversity, evenness, and guild structure were assessed. Prairie quality and community structure of the restored site were compared with 2 remnant prairie sices. Seventy-nine species were documented in the restored prairie with 66 (83%) of those being species associated with other Carolina prairie communities. Big bluestem (Andropogan gerardii Vitman [Poaceae]) and velvet witch grass (Dichanthelium scoparium (Lamarck) Gculd [Poaceae]) had the highest cover values, while blackberry (Rubus orgutus Link [Rosaceae]) and velvet witch grass had tie highest frequency for the restored prairie. Species richness, diversity, and evenness were higher or not significantly afferent for the restored prairie compared with the 2 remnant sites. The woody, C3 grasses, and legume guilds for the restored prairie also had species richness levels that were higher or not significantly different from the remnant sites. In addition, percent cover for the woody, C3 grasses, and legume guilds for the restored prairie were higher or not significantly different from the remnant sites. The results of this study indicate that the restoration of a Piedmont prairie at Crowders Mountain State Park has been successful in its early establishment period. [ABSTRACT FROM AUTHOR]

During the 2007-08 growing seasons we conducted an outcrossing reciprocity study with ramets from 5 big bluestem (Andropogon gerardii) populations from North and South Carolina. We established 15 treatments each at 4 garden sites. Seed germination was low and not significantly different for outcrossed (4.6%) and selfed (2.4%) treatments. However, germination was significantly higher for both outcrossed and selfed seeds from ramets from the Suther Prairie population. The overall mean percent seed set for the outcrossed treatments was 5.9%, and 3.6% for the selfed treatments. There were no significant differences in seed set (maternal effect) for the 5 populations. In addition, there were no significant differences in parental effect in either seed germination or seed set among the 5 populations. Ramets from the Blackjacks Heritage Preserve population (paternal) x Suther Prairie population (maternal) and its reciprocal SP x BJ had the highest combined percent seed germination (21 .3% and 5.8%, respectively). Ramets from the Suther Prairie population (paternal) x Buck Creek Serpentine Barren (maternal), and its reciprocal BC x SP, had the highest combined percentage of seed set (22.7% and 9.6%, respectively). Results from this study suggest that viable seed production is low or absent in big bluestem populations in the Carolinas, particularly in smaller populations. We recommend vegetative material or seeds from the Suther Prairie big bluestem population for potential restoration and establishment of local big bluestem populations. [ABSTRACT FROM AUTHOR]

Andropogon gerardii (Big Bluestem) is a dominant grass of the North American tallgrass prairie. It is also found in remnant populations in the eastern United States, including North and South Carolina, often in association with other species with prairie affinities. We characterized eight A. gerardii population sites across various physiographic regions of North and South Carolina. A total of 362 quadrats (1 m × 1 m) were sampled during the 2006-2008 growing seasons for species occurrence and site and quadrat frequency. Associated species were assigned a commonness index (CI). A Sørensen's Community Coefficient was used to determine floristic similarities among the sites. In addition, soil samples in three quadrats were sampled at each site at three depths (0-10 cm, 11-20 cm, and 21-30 cm) and analyzed for pH; organic C and N contents; extractable P, K, Ca, Mg, Zn, Mn; and CEC (cation exchange capacity). A total of 306 vascular plant species was identified comprising 64 families, including 99 (32%) graminoids. There were 61 (20%) Poaceae and 63 (20%) Asteraceae. Species per quadrat ranged from 1 to 13 with a mean of 5. Andropogon gerardii had the highest CI value (5900), followed by Rubus spp. (1260). Community Coefficient values were , 0.5 for all pairings between sites, indicating high divergence in species composition among even nearby sites. There were 14 rare or watch-listed species identified, including the federal endangered Helianthus schweinitzii at Troy Prairie. A total of 153 (50%) of the species had been previously described as occurring in prairie-like associations. Soil pH values varied from 4.8 to 6.9 among the sites and depths. Ca and Mg nutrient values were also highly variable. Andropogon gerardii was found at high frequencies across all sites, indicating its broad tolerance for a variety of edaphic conditions. [ABSTRACT FROM AUTHOR]

Piedmont prairie communities of the southeastern United States were common prior to European settlement. Suther Prairie in Cabarrus County, North Carolina is among the best-known examples of such an ecosystem. This study provides a complete floristic list of species observed at the site from 1997-2007. Sampling over the 10 yr period included fixed transects and general floristic inventories. During the 2006-07 growing seasons, additional transects and 90 randomly placed 1 m² quadrats were established for sampling species frequency. Soil in six of these random quadrats was sampled at three depths (0-10 cm, 11-20 cm, 21-30 cm) for pH, organic C, total N, and extractable P, K, Ca, Mg, Zn, Mn, Cu, B, and Na. There were 208 species documented during the 10 yr sampling period. In 2006-07 142 new species were identified, but 49 previously documented species were not re-located. Of the 208 species, 66 were graminoids (36 grasses and 30 sedges/rushes). Ninety of these had previously been reported from prairie habitats. Obligate or facultative wetland species comprised 32% of the list. Thirteen species were rare, watch-listed, or uncommon for North Carolina. Big Bluestem (Andropogon gerardii) and Eastern Gamagrass (Tripsacum dactyloides var. dactyloides) had the highest frequency of occurrence during the 2006-07 sampling. Species richness was 6.8 species per m². Levels of Ca and Mg were much higher than normal for Piedmont soils, and there was significant variation in soil C, N, P and Zn levels among the sampled depths. [ABSTRACT FROM AUTHOR]

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

The effects of drill and broadcast planting methods on cover crop biomass production depend on various environmental and operational factors. We investigated whether drilling and broadcasting result in different amounts of biomass production by crimson clover (Trifolium incarnatum L.) and hairy vetch (Vicia villosa Roth) in the upstate of South Carolina, and results vary when seeding rates are increased by 50% from the standard value (22.4 kg ha−1). Field trials were conducted during the fall–winter of 2019–2020 (season one) and 2020–2021 (season two) at the Piedmont Research and Education Center in Pendleton, SC, USA. Cover crop (hairy vetch, crimson clover), planting method (broadcast, drill), and seeding rate (standard, high) treatments were arranged as a 2 × 2 × 2 factorial in both years. Aboveground biomass was measured after 22.5 weeks from planting. At standard seeding rates, crimson clover produced a higher biomass when drilled, rather than broadcasted, whereas biomass production did not vary for hairy vetch. Even with 50% higher seeding rates, broadcasting did not always produce the same biomass as that of drilling for crimson clover. Our results suggest that the advantage of drilling over broadcasting depends upon the cover crop species, as crimson clover responds well to drilling, whereas hairy vetch does not. [ABSTRACT FROM AUTHOR]