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Nutrient use on United States golf courses increases management costs and has the potential to influence ecosystems. Therefore, it is critical to assess nutrient use and management practices to develop and teach best management practices. The objectives of this survey were to measure nutrient use and management practices on United States golf courses in 2021, and to determine if changes occurred since 2006. A survey was developed and distributed via e-mail to 14,033 United States golf facilities, with 1444 responding. From 2006 to 2021, the total projected nitrogen (N), available phosphorus (P2O5), and soluble potash (K2O) applied declined by 41%, 59%, and 54%, to 54,376, 13,761, and 41,386 tons, respectively. These reductions were attributed to course closures, reduced fertilized acres, reduced application rates, and nutrient use restrictions. The percentage of facilities that did not apply P2O5 increased to 21%, which is likely a result of P2O5 application restrictions. Soil testing was associated with greater application rates of N, P2O5, and K2O. Returning clippings, using precision fertilizer applications, reducing turfgrass acreage, and considering N release from soil organic matter were associated with reduced application rates of P2O5. Golf course superintendents have contributed to nationwide reductions in N, P2O5, and K2O, as evidenced by the reduction in fertilized acres and the reduction in nutrient use rates from 2006 to 2021.

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To improve plant quality and fertilizing efficiency, we conducted a study to elucidate the effects of nitrogen (N), phosphorous (P), and potassium (K) fertilizers on the growth, nutrient accumulation, and quality of Lagerstroemia indica plants grown in containers and determine the optimal fertilization levels. Both single-factor and multifactor experiments involving N, P, K fertilizers were designed. Integrated with the plant growth, physiological traits, nutrient levels, and other indices, we used a membership function analysis to comprehensively evaluate plant quality. During the single-factor experiments, the best levels of the single fertilizers applied were 8 g/plant N, 2 g/plant P, and 4 g/plant K. We also found that, within a certain range, N, P, and K fertilizers promoted vegetative growth, increased the chlorophyll, soluble sugar, and soluble protein concentrations, and enhanced nutrient accumulation of L. indica. To avoid the wasting of fertilizers and promote plant quality, the optimal application levels were calculated using a regression analysis. The suggested N, P, and K applications were 6.89 g/plant, 1.97 g/plant, and 3.33 g/plant, respectively. Our results revealed that N, P, and K effect the performance of L. indica container plants, which paves the way for developing reliable and precise fertilizing techniques for growing L. indica.

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Long-term cryopreservation of germplasm is of great importance to maintaining genetic resources. A cryopreservation technology system has not yet been established for Eriobotrya, an important fruit tree in the Rosaceae. In this study, Eriobotrya plants were used as test materials for the following purposes: to study different types of vitrification solution, compare different methods involving programmed cooling vitrification and rapid freezing vitrification; and evaluate the effects of vitrification solution loading time, low-temperature acclimation culture, dark culture, and cryoprotectant use in preculture medium for ultra-low-temperature preservation of Eriobotrya germplasm resources. Plant vitrification solution 1 had the best comprehensive effect on different vitrification solution tests. The programmed cooling and vitrification method yielded a certain survival rate with different vitrification solutions and materials, but the survival rate under the rapid freezing method was 0%. The longer the vitrification solution was loaded, the higher the survival rate. The most suitable time for dark culture of Eriobotrya plants after cryopreservation was 20 days. The preculture medium supplemented with 5% dimethyl sulfoxide resulted in significantly higher preservation than the control medium, and the optimal sucrose concentration was 0.3 mol⋅L−1. A stable, high-survival, and novel cryopreservation procedure for loquat plants was established. The operating procedures are described in a procedural and standardized manner. These findings provide a theoretical basis for research of the cryopreservation of germplasm resources of Eriobotrya plants.

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Industrial hemp (Cannabis sativa) cultivars used for flower, fiber, or seed production are usually considered short-day plants and flower in response to photoperiod. However, some cultivars of hemp are day-neutral, where flower induction may be independent of daylength. Day-neutral cultivars of hemp were planted before recommended dates and studied in field experiments conducted in Watkinsville, GA, in Spring 2020 and 2021. Day-neutral cultivars (Pipeline and Maverick) and photoperiod-sensitive cultivars (Von and Whitehouse Cherry) were planted on 9 and 25 Apr and 11 and 28 May to determine the impact of planting date on hemp flower yield and quality. Planting date did not impact yield of the photoperiod-sensitive cultivars, but yields of day-neutral cultivars decreased as planting date progressed. Average yields of photoperiod-sensitive plants were greater than the day-neutral cultivars in both study years. Cannabinoid concentrations in flowers were affected by cultivar and study year but were not impacted by planting date. Cannabidiol was the most prevalent cannabinoid in flower tissue with concentrations ranging from 6.5% to 10.5%. Flower biomass yields suggest that the spring hemp planting season may be extended using day-neutral cultivars in the southeastern United States.

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Zonal management of cereal–legume cover crop mixtures may help address weed and nitrogen management challenges common in organic reduced tillage systems. During a field study conducted over 3 years in Michigan, we evaluated the effects of cover crop management, tillage, and supplemental mulch on organically produced acorn squash (Cucurbita pepo). During the fall season before squash production, rye (Secale cereale L.) and vetch (Vicia villosa Roth) cover crop mixtures were sown in two distinct spatial arrangements: a “mixed planting,” in which seeds were sown in the same rows, and a “zonal planting,” in which vetch was planted only in the in-row zone and rye was planted only in the between-row zone of the subsequent squash crop. During the following spring season, cover crops were mowed, and four tillage and cover crop management combinations were established: full-width tillage with the mixed planting of rye–vetch (full-till mixed); strip-till with the same mixed planting (strip-till mixed); strip-till with the rye–vetch zonal planting (strip-till zonal); and strip-till with the zonal planting and additional rye mulch added between crop rows immediately after crop establishment (strip-till zonal plus rye). The strip-till mixed treatment resulted in yields equivalent to those of the full-till mixed treatment despite lower available nitrogen and greater early weed competition in some cases. Within strip-till treatments, zonal planting of rye–vetch provided no benefits relative to full-width planting (treatment 2 vs 3) and resulted in lower total cover crop biomass, a higher density of escaped weeds, and lower squash yields during 1 of 3 years. Supplemental rye mulch improved weed suppression and yields in strip-till zonal treatments and resulted in yields equivalent to those of the full-till mixed treatment in all years, but it provided no benefits relative to strip-till mixed. Our results demonstrate that strip-till organic squash production can produce yields equivalent to full-till production in Northern climates, but that zonal planting and supplemental mulch have limited benefits for addressing ongoing weed and nitrogen management challenges. Growers must weigh costs associated with these challenges against potential benefits for soil and pest regulating ecosystem services before adopting these agricultural conservation practices.

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The economic downturns of 2007–09 and the COVID-19 pandemic affected most industries in the United States, including landscape services and equipment sales, and provoked both short-term disruptions and long-term changes. To understand how the landscaping industry has responded, we investigated patterns of consumer expenditures on landscape services and equipment from 2009 through 2021 using a representative sample of 76,895 US households. We categorized US households as detached single-family residents and townhouse residents to more fully articulate the factors that turned potential consumers into purchasers and the factors that affected purchasers’ expenditures. We used a double-hurdle model to identify key factors that drive consumer demand for landscape services and equipment over time, including social-demographics, geographic characteristics, housing conditions, year and seasonal trends, and the COVID-19 pandemic. We found that during the studied period, the demand for landscape services declined in terms of both the percentage of consumers purchasing the services and the purchasers’ average expenditures, while the demand for do-it-yourself (DIY) equipment remained relatively unchanged. In response to the COVID-19 pandemic, the percentage of consumers who purchased landscape services increased, while the expenditures on landscape services decreased in 2020 and then began to rebound in 2021, but not enough to reverse the overall downward trend. In contrast, purchases of DIY equipment were relatively stable in response to the COVID-19 pandemic and mainly relied on current consumers.

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The purpose of this study was to examine the ability of preschool gardening programs to help children develop their ability to delay gratification. Children today face many opportunities for instant gratification, although the ability to delay gratification in early childhood has been linked to numerous benefits later in life. Opportunities to train children in the ability to delay gratification present educational challenges, in that it competes with other academic training needs, and it can be difficult to find programs that are interesting to young children. The population for this study was preschool children ranging in age from 2 to 6 years, with treatment and control groups drawn from different schools. Participants were tested individually and timed to determine their ability to delay gratification, with promises of larger rewards if the child could wait for 15 minutes. The results of this study did not identify a significant change in all children’s ability to delay gratification after a gardening program. However, analyses showed that females appear to have responded more positively to the gardening treatment in their ability to delay gratification, whereas males in the control group benefited more from traditional school lessons.

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Drought is one of the major environmental challenges constraining the production of agricultural crops, including carrot. Seed germination is the initial and most critical stage of crop establishment, and it is very sensitive to drought stress because water scarcity affects the enzymatic solubilization of stored metabolites in seeds that provide energy for the growth of germinating embryo. Few studies evaluating the effect of drought stress on carrot seed germination of more than a few cultivars grown under stress have been published. Therefore, the present study was designed to define the appropriate osmotic potential for evaluating drought tolerance of carrot, evaluate the response of diverse carrot germplasm to drought stress during seed germination to identify drought-tolerant accessions that may be used by plant breeders, and evaluate the relation between amylase activity and germination rate of drought-tolerant and drought-sensitive accessions. To identify an appropriate screening osmotic potential, two commercial cultivars and two United States Department of Agriculture inbreeds were evaluated at six osmotic potentials (00, −0.30, −0.51, −0.58, −0.80, and −1.05 MPa); −0.58 MPa was identified as the optimal osmotic potential for screening the drought tolerance of carrot seed. Cultivated and wild carrot plant introductions (PIs) (n = 200 and n = 50, respectively) from the National Plant Germplasm System were evaluated for drought tolerance under nonstress and simulated drought stress conditions (00 MPa and −0.58 MPa, respectively) by calculating the absolute decrease (AD) in percent germination, inhibition index (II), relative drought tolerance (RDT), and drought tolerance index (DTI). All measurements of drought tolerance identified significant differences among accessions; the AD in seed germination ranged from 0.0% to 69.3%, II ranged from 0.0% to 80.2%, RDT ranged from 0.2 to 1.0, and DTI ranged from 0.13 to 1.47. All wild carrot accessions displayed low levels of drought tolerance, but PI 652387 and PI 177381 (both from Turkey) and PI 274297 (Pakistan) were most drought-sensitive, whereas cultivated accessions PI 643114 (United States), PI 652208 (China), and PI 502347 (Uzbekistan) were most drought-tolerant. Tolerant accessions displayed much higher α-amylase activity under nonstress conditions than sensitive accessions, and α-amylase activity of tolerant accessions was also reduced less with seed germination under increasing osmotic potential (range, 0.0 to −1.05 MPa) than sensitive accessions over 24, 48, and 72 hours of seed germination. This is the first evaluation of drought stress tolerance during seed germination and the enzymatic response of diverse carrot germplasms under simulated drought stress.

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