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Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a new human disease with few effective treatments.sup.1. Convalescent plasma, donated by persons who have recovered from COVID-19, is the acellular component of blood that contains antibodies, including those that specifically recognize SARS-CoV-2. These antibodies, when transfused into patients infected with SARS-CoV-2, are thought to exert an antiviral effect, suppressing virus replication before patients have mounted their own humoral immune responses.sup.2,3. Virus-specific antibodies from recovered persons are often the first available therapy for an emerging infectious disease, a stopgap treatment while new antivirals and vaccines are being developed.sup.1,2. This retrospective, propensity score-matched case-control study assessed the effectiveness of convalescent plasma therapy in 39 patients with severe or life-threatening COVID-19 at The Mount Sinai Hospital in New York City. Oxygen requirements on day 14 after transfusion worsened in 17.9% of plasma recipients versus 28.2% of propensity score-matched controls who were hospitalized with COVID-19 (adjusted odds ratio (OR), 0.86; 95% confidence interval (CI), 0.75-0.98; chi-square test P value = 0.025). Survival also improved in plasma recipients (adjusted hazard ratio (HR), 0.34; 95% CI, 0.13-0.89; chi-square test P = 0.027). Convalescent plasma is potentially effective against COVID-19, but adequately powered, randomized controlled trials are needed. Convalescent plasma for treatment of hospitalized patients with COVID-19 is associated with improved survival in a retrospective comparison with matched controls, supporting further study in randomized controlled trials., Author(s): Sean T. H. Liu [sup.1] [sup.2] , Hung-Mo Lin [sup.3] , Ian Baine [sup.4] , Ania Wajnberg [sup.5] , Jeffrey P. Gumprecht [sup.1] , Farah Rahman [sup.1] , Denise [...]

Background: Convalescent plasma (CP) for treatment of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has shown preliminary signs of effectiveness in moderate to severely ill patients in reducing mortality. While studies have demonstrated a low risk of serious adverse events, the comprehensive incidence and nature of the spectrum of transfusion reactions to CP is unknown. We retrospectively examined 427 adult inpatient CP transfusions to determine incidence and types of reactions, as well as clinical parameters and risk factors associated with transfusion reactions. Study Design and Methods: Retrospective analysis was performed for 427 transfusions to 215 adult patients with coronavirus 2019 (COVID‐19) within the Mount Sinai Health System, through the US Food and Drug Administration emergency investigational new drug and the Mayo Clinic Expanded Access Protocol to Convalescent Plasma approval pathways. Transfusions were blindly evaluated by two reviewers and adjudicated by a third reviewer in discordant cases. Patient demographics and clinical and laboratory parameters were compared and analyzed. Results: Fifty‐five reactions from 427 transfusions were identified (12.9% incidence), and 13 were attributed to transfusion (3.1% incidence). Reactions were classified as underlying COVID‐19 (76%), febrile nonhemolytic (10.9%), transfusion‐associated circulatory overload (9.1%), and allergic (1.8%) and hypotensive (1.8%) reactions. Statistical analysis identified increased transfusion reaction risk for ABO blood group B or Sequential Organ Failure Assessment scores of 12 to 13, and decreased risk within the age group of 80 to 89 years. Conclusion: Our findings support the use of CP as a safe, therapeutic option from a transfusion reaction perspective, in the setting of COVID‐19. Further studies are needed to confirm the clinical significance of ABO group B, age, and predisposing disease severity in the incidence of transfusion reaction events. [ABSTRACT FROM AUTHOR]

As police departments across the United States equip officers with body worn cameras (BWCs), research has focused on the technology’s impact on police interactions with citizens, officer misconduct, officer use of force, and false allegations against police. Given the large number of police agencies implementing BWCs across the country (numbering in the thousands), there will be a growing number of opportunities for BWC evaluations and expectations that these programs will be evaluated. Studying the implementation of BWCs presents a number of challenges to both researchers and police agencies, particularly when large police organizations are involved. Drawing on our experiences involving a BWC experiment with the Las Vegas Metropolitan Police Department, this article discusses the programmatic challenges of implementing a BWC program in a large agency (technical, political, and administrative) while simultaneously evaluating the program using a randomized controlled trial design. [ABSTRACT FROM AUTHOR]

This study sought to determine whether deficient Igf1 expression in osteocytes would affect loading-induced osteogenic response. Tibias of osteocyte Igf1 conditional knockout (KO) mice (generated by cross-breeding Igf1 floxed mice with Dmp1-Cre transgenic mice) and wild-type (WT) littermates were subjected to four-point bending for 2 wk. Microcomputed tomography confirmed that the size of tibias of conditional mutants was smaller. Loading with an equivalent loading strain increased periosteal woven bone and endosteal lamellar bone formation in WT mice but not in conditional KO mice. Consistent with the lack of an osteogenic response, the loading failed to upregulate expression of early mechanoresponsive genes (Igf1, Cox-2, c-fos) or osteogenic genes (Cbfa-1, and osteocalcin) in conditional KO bones. The lack of osteogenic response was not due to reduced osteocyte density or insufficient loading strain. Deficient osteocyte Igf1 expression reduced the loading-induced upregulation of expression of canonical Wnt signaling genes (Wnt10b, Lrp5, Dkk1, sFrp2). The loading also reduced (by 40%) Sost expression in WT mice, but the loading not only did not reduce but upregulated (~1.5-fold) Sost expression in conditional KO mice. Conditional disruption of Igf1 in osteocytes also abolished the loading-induced increase in the bone β-catenin protein level. These findings suggest an impaired response in the loading-induced upregulation of the Wnt signaling in conditional KO mice. In summary, conditional disruption of Igf1 in osteocytes abolished the loading-induced activation of the Wnt signaling and the corresponding osteogenic response. In conclusion, osteocyte-derived IGF-I plays a key determining role in bone mechanosensitivity. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the salt tolerance of five cotton genotypes [three Gossypium hirsutum L. (DN 1, DP 491, and FM 989) and two G. barbadense L. (Cobalt and Pima S-7)] under NaCl or Na2SO4 salinity conditions at similar osmotic potentials (100 mM NaCl vs. 70 mM Na2SO4 and 150 mM NaCl vs. 111 Na2SO4). To investigate whether the addition of calcium sulfate could alleviate the deleterious salinity effect, two more treatments were prepared by adding 10 mM CaSO4 to 150 mM NaCl and 111 mM Na2SO4 solutions. All genotypes had significant growth reduction in all salt treatments as compared to their respective controls. Whereas Upland and Pima cotton did not differ in response to salt, DP 491 had lower growth reduction as compared to other genotypes and was therefore more salt tolerant. Salt type did not affect the growth of FM 989 and Pima S-7; however, dry weight (DW) of all organs were reduced to a greater extent by NaCl than by Na2SO4 in most organs in Pima Cobalt, shoot and total DW in DP 491, and root DW in DN 1. The addition of CaSO4 alleviated some detrimental effects in DN 1 caused by NaCl and in Pima Cobalt caused by Na2SO4. The five genotypes also responded to salt treatments differently in that DN 1 and DP 491 had higher Na+ and Cl- concentrations and higher leaf osmotic potentials than the other three genotypes except for higher Cl- concentrations in Cobalt. These results indicated that diversity of salt-tolerant mechanisms existed among the five cotton genotypes. [ABSTRACT FROM AUTHOR]

Impacts of wastewater land application on desert vegetation are not adequately known. In a 4-yr field study, we evaluated the effects of treated, saline−sodic industrial effluent application on the aboveground vegetation biomass and mineral accumulation of a Chihuahuan Desert shrubland. The vegetation included two shrubs, Larrea tridentata (DC.) Coville and Prosopis glandulosa Torr. var. glandulosa, and seven herbaceous species in the intershrub spaces. Early summer fruit dry weights on terminal branches of the irrigated shrubs were 3 to 14 times higher than those on the non-irrigated shrubs. The combined irrigated vegetation produced 2 Mg of additional dried biomass per ha above that of the non-irrigated plot, and contained excesses of total Kjeldahl-N (TKN) and Ca2+ equivalent to 18% of effluent N deposition and 12% of effluent Ca2+ deposition. Under irrigated and highly sodic conditions (soil sodium adsorption ratio up to 35), the herbaceous Lepidium alyssoides A. Gray var. alyssoides produced the highest biomass of all plant species. However, there was a decline in plant species diversity as L. alyssoides became dominant in the irrigated intershrub spaces. While the findings demonstrate the natural attenuation of effluent minerals by native Chihuahuan Desert vegetation, highly sodic conditions may alter the composition of the vegetation community. [ABSTRACT FROM PUBLISHER]

Wildflowers are good candidates for water-wise landscapes because many of them are drought-tolerant after establishment. Little information is available regarding whether these herbaceous wildflowers are tolerant to salt stress. Container experiments were carried out in a greenhouse and a shadehouse under semiarid climate conditions to investigate the salt tolerance of six native wildflowers: Saiviafarinacea (mealy cup sage), Berlandiera lyrata (chocolate daisy), Ratibida columnaris (Mexican hat), Oenothera elata (Hooker's evening primrose), Zinnia grandiflora (plains zinnia), and Monarda citriodora (lemon horsemint). In the greenhouse experiment, mealy cup sage, Hooker's evening primrose, and plains zinnia were irrigated with a saline solution with an electrical conductivity (EC) of 1.5 (control, nutrient solution), 2.8, 4.1, 5.1, or 7.3 dS·m-1 for 45 days. All plants survived except for plains zinnia at EC of 7.3 dS·m-1. Shoot dry weights decreased as EC of irrigation water increased for all three species. In the shadehouse experiment (second year), plants of all species (plains zinnia was not included) were irrigated with saline solutions at EC of 0.8 (control, tap water), 2.8, 3.9, 5.5, or 7.3 dS·m-1 for 35 days. Plants were fertilized with slow-release fertilizer in the shadehouse experiment. After 5 weeks of treatment, all plants of lemon horsemint in the elevated salinity treatments, regardless of EC levels, were dead. The visual foliar salt damage rating was lowest for lemon horsemint. Chocolate daisy had low survival percentages and low foliar ratings at EC of 5.5 dS·m-1 and 7.3 dS.m-1. For the other three species, survival percentages were 80% and 90% at EC of 7.3 dS·m-1. Hooker's evening primrose and mealy cup sage had similar low foliar visual ratings at EC of 7.3 dS·m-1, whereas Mexican hat plants had high foliar visual ratings regardless of salinity treatment. All species had similar high uptake of Na+ in shoots, whereas Hooker's evening primrose had slightly higher Cl- concentrations compared with other species. Based on these results, lemon horsemint was most sensitive to salinity stress followed by chocolate daisy. Hooker's evening primrose and mealy cup sage were moderately tolerant and may be irrigated with low salinity water at EC of less than 3.9 dS·m-1. Mexican hat was the most tolerant among the six species. [ABSTRACT FROM AUTHOR]

Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a 0.4-ha Chihuahuan Desert shrubland to assess the deposition and recovery of effluent components and changes in soil quality vis-à-vis a non-irrigated area. Effluent irrigation supplied 26% of the average annual nonstressed evapotranspiration (ET) of the native shrubs [Larrea tridentata (DC.) Coville and Prosopis glandulosa Torr. var. glandulosa], and increased both soil stress factors (sodicity, salinity, and pH) and soil fertility (N, P, and K). After 3 yr, the soil saturation extract electrical conductivity (ECe) reached as high as 6.1 dS m−1 and Cl− 76 molc m−3 at 105 cm depth under irrigated L. tridentata. After 4 yr, saturation extract sodium adsorption ratio (SARe) reached 25–35 at 7.5 cm under the irrigated shrubs and intershrub spaces. There were 27 Mg ha−1 of cumulative ionic deposits to the site comprised mostly of Na+, Cl−, and CaCO3 equivalent alkalinity, with soil analysis recovering most of the deposits (>57%) except for K+ and Na+ (8% to 13%). Subsurface leaching of and P was detected within the upper 1 m soil depth after 4 yr, and a high downward mobility of Cl− revealed the potential for deeper leaching at higher N loading rates. While long-term effects on the natural vegetation are unknown, results contribute to a limited scientific database for sustainable wastewater land application in semiarid regions. [ABSTRACT FROM PUBLISHER]

Two greenhouse experiments were conducted to quantify growth responses of Jatropha curcas to a range of salt and drought stresses. Typical symptoms of salinity stress such as leaf edge yellowing were observed in all elevated salinity treatments and the degree of the foliar salt damage increased with the salinity of irrigation water. Total dry weight (DW) of Jatropha plants was reduced by 30%, 30%, and 50%, respectively, when irrigated with saline solutions at electrical conductivity of 3.0, 6.0, and 9.0 dS m-1 compared to that in the control. Leaf Na+ concentration was much higher than that observed in most glycophytes. Leaf Cl- concentrations were also high. In the drought stress experiment, plants were irrigated daily with nutrient solution at 100%, 70%, 50%, or 30% daily water use (DWU). Deficit irrigation reduced plant growth and leaf development. The DW of leaves, roots, and total were reduced in the 70%, 50%, and 30% DWU compared to the 100% DWU control treatment. In summary, salinity stress and deficit irrigation significantly reduced the growth and leaf development of greenhouse-grown Jatropha plants. [ABSTRACT FROM AUTHOR]

The growth and physiological responses of four maize inbred lines (CUBA1, B73, B5C2, and BR1) and four sorghum hybrids (SS304, NK7829, Sordan 79, and KS585) to salinity were determined. Fifteen days after sowing, seedlings were irrigated with nutrient solution (control) at electrical conductivity (EC) of 1.5 dSm-1 or saline solution at EC of 8.0 dSm-1 (salt treatment) for 40 days. Dry weight of shoots in maize was reduced by 58%, 65%, 62%, and 69% in CUBA1, B73, B5C2, and BR1, respectively, while that of sorghum was reduced by 51%, 56%, 56%, and 76% in SS304, NK7829, Sordan79, and KS585, respectively, in the salt treatment compared to their respective control. Salinity stress reduced all or some of the gas exchange parameters, leaf transpiration (E), stomatal conductance (gs), and net photosynthetic rate (Pn) in the late part of the experiment for both crops. Salinity treatment greatly increased Na+ uptake in allmaize genotypes but did not affect the Na+ uptake in sorghum, regardless of genotype. Inmaize, CUBA1 was slightly more resistant to salt stress, while BR1 was more sensitive to salt stress. In sorghum, Sordan79 was the most tolerant genotype, and KS585 was the least tolerant genotype. [ABSTRACT FROM AUTHOR]

Texas mountain laurel (Sophora secundiflora) is a native shrub tolerating drought, heat, windy conditions, and alkaline or wet soils. However, its availability is somewhat low and little information is available on nutrient requirement and other culture information. Two greenhouse experiments were conducted to quantify the responses of Texas mountain laurel to different forms and rates of nitrogen (N) fertilizer. In Expt. 1, 1-year old seedlings were treated for 194 days with three NO3:NH4 ratios at 25:75, 50:50, and 75:25 and two rates of N at 100 and 200 mg⋅L-1 in a factorial design. There was no interaction between the N rate and form on any growth parameters. Nitrogen form did not significantly affect shoot dry weight, root dry weight, root--to-shoot ratio, or the total dry weight. There was no significant difference between N rate of 100 and 200 mg⋅L-1 on root dry weight, root-to-shoot ratio, or the total dry weight. The shoot dry weight of Texas mountain laurel fertilized with 100 mg⋅L-1 was higher compared with that of the plants fertilized at 200 mg⋅L-1. The reduced shoot dry weight at N of 200 mg⋅L-1 was the result of the higher substrate salinity. In Expt. 2, seedlings were fertilized with five N rates (50, 100, 150, 200, and 250 mg⋅L-1) for 203 days. Plants watered with 150, 200, and 250 mg⋅L-1 were taller than those fertilized with 50 mg⋅L-1. The shoot height of plants watered with 100 mg⋅L-1 was only significantly different from 50 mg⋅L-1. For rapid growth of Texas mountain laurel, a N rate range of ≈150 mg⋅L-1 was recommended supplied with a combination of NO3-N and NH4-N in the ratios of 0.3 to 3.0. [ABSTRACT FROM AUTHOR]

Abstract: Salt tolerance of five cultivars of Capsicum annuum L. Early Jalapeno, Golden Treasure, NuMex Sweet, NuMex Joe E. Parker, and Santa Fe Grande, two cultivars of C. chinense Jacq. Habanero and Pimienta De Chiera, and one accession of C. annuum, NMCA 10652, were evaluated in a field study. Seedlings were transplanted in late May to field raised beds containing loamy sand soils in a semi-arid environment. Plants were well irrigated throughout the experiment. Three saline solution treatments, prepared by adding NaCl, MgSO4, and CaCl2 to tap water at different amounts to create three salinity levels of 0.82dSm−1 (control, tap water), 2.5dSm−1, and 4.1dSm−1 electrical conductivity (EC), were initiated on 15th June and ended in late August. Among the eight varieties, NMCA 10652 had the highest survival percentage at 100% in the 4.1dSm−1 treatment, followed by ‘Early Jalapeno’, ‘NuMex Sweet’, ‘Pimienta De Chiera’, ‘Santa Fe Grande’, ‘Golden Treasure’, and ‘NuMex Joe E. Parker’. ‘Habanero’ had the lowest survival at 28%. Compared to control, final shoot dry weight of the plants irrigated with saline solution at 4.1dSm−1 was reduced by 92% in ‘Habanero’, followed by ‘Golden Treasure’ at 80%. For fruit fresh weight in 4.1dSm−1 vs. control, ‘Habanero’ had the highest reduction at 86%, followed by ‘Golden Treasure’ at 74%, while NMCA 10652 and ‘Santa Fe Grande’ had the least at 26% and 19%, respectively. NMCA 10652, the most tolerant to salinity, had the lowest leaf Na+ accumulation, while ‘Habanero’, the most sensitive to salinity, had the highest Na+ in the leaves. For leaf Cl−, ‘Early Jalapeno’ had the highest, while ‘Habanero’ had the lowest Cl− accumulation in the leaves. Generally, sensitive varieties accumulated more Na+ and/or Cl− in leaves, except for ‘Early Jalapeno’, which was relatively tolerant to salinity but had high Na+ and Cl− accumulation in leaves. [Copyright &y& Elsevier]

High soil salinity often results in poor stand establishment, reduced plant growth, and reduced yield of many horticultural crops such as peppers (Capsicum annuum). We investigated the effects of soil salinity and soil type on seedling emergence and growth of four commercial peppers ('NuMex Joe E. Parker', 'NuMex Nematador', 'NuMex Primavera', and 'Jupiter') in greenhouse experiments. Seeds were sown in either a loamy sand or a silt loam soil in pots and irrigated with saline solutions at electrical conductivity of 0.9 (tap water), 3.0, or 6.0 dS.m&#sup1; (Expt. 1) or at 0.0 [reverse osmosis (RO) water], 0.9, or 1.5 dS.m&#sup1; (Expt. 2). No seedling emergence was observed in treatments irrigated with 3.0 or 6.0 dS.m&#sup1; solutions. The salinity at the top soil layer increased linearly with time when subirrigated with tap and saline solutions in both soil types, whereas no substantial increase in soil salinity was found when subirrigated with RO water or overhead irrigation with tap water. Salt accumulation at the top soil layer was greater in loamy sand than in silt loam. Seedling emergence percent subirrigated with RO water ranged from 70% to 80% in loamy sand and 45% to 70% in silt loam, depending on pepper cultivars. When subirrigated with tap water and saline solutions, the emergence percent ranged from 0% to 60%, depending on pepper and soil types. In Expt. 3, seedlings were germinated in commercial potting mix and grown in 1.8-L pots containing commercial potting mix. Saline solution treatments of 1.4 (control, nutrient solution), 2. 1, 2.9, 3.5, or 4.2 dSm&#sup1; were initiated when seedlings had 11 to 13 leaves. Five weeks after initiating saline water irrigation, the reduction in shoot dry weight was greater in 'Jupiter' and 'NuMex Primavera' as compared with 'NuMex Joe E. Parker' and 'NuMex Nematador', but the differences were small. [ABSTRACT FROM AUTHOR]

Chile peppers are economically important crops in southern regions of the United States. Limited information is available on irrigation management with low-quality water or on salt-affected soils. The objective of this study was to determine the relative salt tolerance of 20 genotypes of chile peppers. In Expt. 1, seeds of selected pepper types (Anaheim, Ancho, Cayenne, Paprika, Jalapeño, Habanero, and Serrano) were germinated in potting mix and seedlings were grown in 2.6-L pots. Six weeks after sowing, salinity treatments were initiated by irrigating plants with nutrient solutions of different electrical conductivities (ECs): 1.4 (control), 3.0, or 6.0 dS.m -1. After 1 month of initiating treatments, shoots were harvested and dry weights were determined. All plants survived and no visual salt injury was observed regardless of pepper variety and treatment. There were no statistical differences between control and saline solution treatments in final height and shoot dry weight of Habanero 1, 'Early Jalapeño', 'AZ-20', 'NuMex Joe E. Parker', and 'NuMex Sandia'. In Expt. 2, seeds of 20 genotypes were directly sown in 2.6-L containers filled with loamy sand. Saline water irrigation was initiated 37 days after sowing by irrigating plants either with saline (nutrient solution based, similar to Expt. 1) or nutrient solution (control). More than half the genotypes did not have 100% survival in the salinity treatment. Ancho 1, Ancho 2, Cayenne 1, 'Early Jalapeño', and 'AZ-20' had 100% survival regardless of salinity treatment. No plants of 'TAM Mild Habanero' survived when irrigated with saline water and less than half of the plants survived in the control. The relative tolerance of chile genotypes to salinity varied with substrate in some genotypes. From the combined results of the two experiments, the 20 pepper genotypes were ranked for salt tolerance based on seedling survival, visual quality, and growth. 'Early Jalapeño' and 'AZ-20' were relatively tolerant to salinity among the 20 genotypes, whereas 'TAM Mild Habanero' and 'Ben Villalon' were sensitive. Ancho 1, Ancho 2, Cayenne 1, and Cayenne 2 also had relatively high tolerance based on survival and visual quality, although shoot growth was reduced significantly. [ABSTRACT FROM AUTHOR]

Bedding plants are extensively used in urban landscapes. As high-quality water supply becomes limited in many parts of the world, the use of recycled water with high salt levels for landscape irrigation is being encouraged. Therefore, information on salt tolerance of bedding plants is of increasing importance. Two experiments were conducted, one in a 25% light exclusion shadehouse in summer (Expt. 1) and the other in a greenhouse in winter (Expt. 2). Plants were irrigated with saline solution at electrical conductivities of 0.8, 2.8, 4.0, 5.1, or 7.4 dS·m-1 created by adding NaCI, MgSO4, and CaCI2 to tap water to simulate the composition of local reclaimed water. In Expt. 1, shoot dry weight (DW) at the end of the experiments was reduced in all species at 7.4 dS·m-1 compared with the control (0.8 dS·m-1). The magnitude of reduction varied with species and cultivars. The salinity thresholds of irrigation water in which growth reduction occurred were 4.0 dS·m-1 for angelonia (Angelonia angustifolia) cultivars and ornamental pepper (Capsicum annuum) 'Calico' and 4.0 to 5.1 dS·m-1 for helenium (Helenium amarum), licorice plant (Helichrysum petiolatum), and plumbago (Plumbago auriculata). Shoot DW and growth index of ornamental pepper 'Black Pearl' and vinea (Catharanthus roseus) 'Rose' decreased linearly as salinity increased. All plants survived in Expt. 1 regardless of treatment, except for ornamental pepper 'Purple Flash'. No visual injuries were observed in Expt. 1 regardless of treatment. Leaf sodium (Na) and chlorine (CI) concentrations varied with species and treatments. Ornamental pepper 'Black Pearl' had the highest leaf CI concentrations at higher salinities compared with other species and cultivars. Leaf Na concentrations in licorice plant and plumbago were in the range of 10 to 30 g·kg-1 DW, higher than those in other species. In Expt. 2, shout DW was reduced by salinity, treatments in ornamental pepper 'Black Pearl', plumbago, and angelonia but not in other species. The three ornamental peppers, 'Black Pearl', 'Calico', and 'Purple Flash', exhibited slight follar injuries on some plants in Expt. 2 as a result of high salinity in the root zone in the highest salinity treatment. Ornamental pepper 'Black Pearl' was most sensitive to salinity, stress. In general, the bedding plants tested in this study are moderately tolerant to salt stress and may be irrigated with saline water up to 4.0 dS·m-1 with little reduction in aesthetical appearance. [ABSTRACT FROM AUTHOR]

Use of reclaimed water to irrigate urban landscapes will likely increase because fresh water supply is diminishing and the population continues to grow in the semiarid southwestern United States. Salt tolerance of two native landscape woody ornamentals, Texas mountain laurel (Sophora secundiflora) and Mexican redbud (Cercis canadensis var. mexicana), was investigated in a greenhouse experiment. Seedlings of the two species were grown in two substrates mixed with composted mulch and a commercial potting mix at two ratios and irrigated with saline solutions at three salinity levels: 1.6 (control, nutrient solution), 3.0, or 6.0 dS*m-1 electrical conductivity (EC). There was no interaction between substrate and EC of irrigation water. Foliar salt damages such as leaf drop, leaf curl, and edge burn were observed in Mexican redbud when the plants were irrigated with solutions at EC of 3.0 and 6.0 dS*m-1. No symptoms were observed on Texas mountain laurel plants, although plants irrigated at EC of 3.0 and 6.0 dS*m-1 were smaller compared with controls. Shoot growth and elongation of both species were reduced by the elevated salinity of irrigation water, and the reduction in Mexican redbud was greater than Texas mountain laurel. Leaf photosynthesis rate and leaf stomatal conductance were also reduced in Texas mountain laurel by the elevated salinity of irrigation water. Tissue Na+ and Cl- concentrations were higher in Texas mountain laurel irrigated with water of elevated salinity. [ABSTRACT FROM AUTHOR]

Salt-tolerant landscape plants are needed for arid and semiarid regions where the supply of quality water is limited and soil salinization often occurs. This study evaluated growth, chloride (Cl) and sodium (Na) uptake, relative chlorophyll content, and chlorophyll fluorescence of three rose rootstocks [Rosa xfortuniana Lindl., R. multiflora Thunb., and R. odorata (Andr.) Sweetl irrigated with saline solutions at 1.6 (control), 3.0, 6.0, or 9.0 dS⋅m-1 electrical conductivity in a greenhouse. After 15 weeks, most plants in 9.0 dS⋅m-1 treatment died regardless of rootstock. Significant growth reduction was observed in all rootstocks at 6.0 dS. ⋅m-1 compared with the control and 3.0 dS.m⋅m-1, but the reduction ih R. x fortuniana was smaller than in the other two rootstocks. The visual scores of R. multiflora at 3.0 and 6.0 dS⋅m-1 were slightly lower than those of the other rootstocks. Rosa odorata had the highest shoot Na concentration followed by R. multiflora; however, R. multiflora had the highest root Na concentration followed by R. odorata. All rootstocks had higher Cl accumulation in all plant parts at elevated salinities, and no substantial differences in Cl concentrations in all plant parts existed among the rootstocks, except for leaf Cl concentration in R. multiflora, which was higher than those in the other two rootstocks. The elevated salinities of irrigation water reduced the relative chlorophyll concentration, measured as leaf SPAD readings, and maximal photochemical efficiency of photosystem II (PSII) and minimal fluorescence (Fo)/maximum fluorescence (Fv/Fm), but the largest reduction in Fv/Fm was only 2.4%. Based on growth and visual quality, R. x fortuniana was relatively more salt-tolerant than the other two rootstocks and R. odorata was slightly more salt-tolerant than R. multiflora. [ABSTRACT FROM AUTHOR]

Ten herbaceous perennials and groundcovers were grown in raised beds-from June to September in a dry, hot desert environment and micro-spray drip irrigated with synthesized saline solutions at electrical conductivity of 0.8 (tap water), 3.2, or 5.4 dS/m. Plant height and two perpendicular widths were recorded monthly to calculate the growth index. Landscape performance was assessed monthly by visual scores. Salinity did not affect the visual scores in Achillea millefolium L., Gaillardia aristata Pursh, Lantana x hybrida 'New Gold', Lonicera japonica Thunb. 'Halliana', and Rosmarinus officinalis L. 'Huntington Carpet' throughout the experiment. Glandularia canadensis (L.) Nutt. 'Homestead Purple' performed better than Glandularia x hybrida (Grönland & Rümpler) G L. Nesom & Pruski. Lantana montevidensis (Spreng.) Brig. had lower visual scores at 5.4 dS/m compared to the control and 3.2 dS/m. Most plants of Rudbeckia hirta L. did not survive when irrigated at 3.2 dS/m or 5.4 dS/m. Shoot biomass of A. millefolium, G. aristata, L. x hybrida, L. japonica, R. officinalis, and V macdougalii was not influenced by the salinity of irrigation' water. Therefore, A. millefolium, G aristata, L. x hybrida, L. japonica, and R. officinalis can be irrigated with non-potable water at salinity up to 5.4 dS/m with little reduction in growth and aesthetic appearance. [ABSTRACT FROM AUTHOR]

A study was conducted to characterize the response of Gaillardia aristata Pursh to salinity (0.8, 2.0 or 4.0 dS/m) and growing media: 100% perlite (Perlite), 100% Sunshine Mix No. 4 (Mix), 1 to 1 (by vol) perlite and Sunshine Mix No. 4 (Perlite Mix), or 1 to 1 Sunshine Mix No. 4 and composted mulch (Mix Mulch). Type of medium did not influence shoot dry weight (DW). However, root to shoot DW ratio was highest for plants grown in Perlite. Shoot DW of plants irrigated with tap water (0.8 dS/m) was higher compared to those irrigated with saline solution at 2.0 or 4.0 dS/m, except for those grown in Mix. Salinity did not alter the root to shoot DW ratio. In general, elevated salinity led to relatively short plants. Plants were taller when grown in Perlite or Mix Mulch with fewer lateral shoots compared to plants grown in Mix and Perlite Mix. Flower bud abortion occurred in plants grown in Mix or Perlite Mix, while this phenomenon was not observed in plants grown in Perlite or Mix Mulch. Overall, plants performed better in Perlite and Mix Mulch than Mix and Perlite Mix. [ABSTRACT FROM AUTHOR]

Abstract: In order to use reclaimed water to irrigate landscape plants and minimize damage and loss, salinity tolerance of commonly used landscape plants needs to be determined and characterized. Eight herbaceous perennials and groundcovers were obtained from a local nursery, transplanted to 2.6-L plastic containers and grown in the greenhouse for 2 weeks before saline irrigation at electrical conductivity (EC) of 0.8 (tap water), 3.2, 6.4, or 12dSm−1 were initiated. Plants were irrigated with measured amount of saline solutions to obtain 30% leaching when approximately 50% water had been depleted. After 12 weeks, four plants in each treatment were destructively harvested and dry weights of shoots and roots were determined. Three Penstemon species (P. eatonii A. Gray, P. pseudospectabilis M.E. Jones, and P. strictus Benth.) and Lavandula angustifolia Mill. at 6.4 and 12dSm−1 and most at 3.2dSm−1 did not survive. Shoot dry weight of Delosperma cooperi (Hook.f.) L. Bolus decreased by 25% at 12dSm−1, but there were no significant differences among the rest of the treatments. All plants of Teucrium chamaedrys L. survived but growth was reduced significantly with lower visual scores as salinity of irrigation water increased. Although growth was reduced in Gazania rigens (L.) Gaertn. as salinity increased, no other signs of stress or injury were observed. Ceratostigma plumbaginoides Bunge had reduced growth at 3.2dSm−1 and higher EC levels compared to the control, older leaves showed reddish pigmentation at 6.4dSm−1, whereas those at 12dSm−1 did not survive. Ion concentrations of shoot and root tissue at the end of the experiment on surviving plants were also affected by salinity levels and varied among species. Among the tested species, D. cooperi and G. rigen indicated a relatively high tolerance to salinity, T. chamaedrys and C. plumbaginoides were moderately tolerant, and the rest were less tolerant. [Copyright &y& Elsevier]

Use of recycled water to irrigate urban landscapes may be inevitable, because the freshwater supply has been diminishing and the population continues to grow in the arid and semiarid southwestern United States. However, little information exists on the performance of landscape plants irrigated with nonpotable water. Two greenhouse studies were conducted during the summer and the fall to characterize the relative salt tolerance of five herbaceous perennials by irrigating the plants with a saline solution at an electrical conductivity (EC) of 0.8 dS·m-1 (tap water), 2.0 dS·m-1, or 4.0 dS·m-1. In the summer study, after 10 weeks of treatment, Achillea millefolium L., Gaillardia aristata Foug., and Salvia coccinea Juss ex J. had an aesthetically acceptable appearance for landscape performance (visual quality scores of 4 points or more), whereas Agastache cana (Hook.) Woot. & Standl. and Echinacea purpurea (L.) Moench had relatively low tolerance to salinity. Dry weight of shoots ofA. miilefolium, A. cana, and (7. arstata was lower at elevated salinity levels. In the fall study, A. millefolium, E. purpurea, {7,. arstata, and S. coccinea had acceptable growth and visual quality at elevated salinity levels, whereas A. cana had lower quality and reduced growth. Dry weight of shoots was lower in G. arstata and A. millefolium at an EC of 2.0 dS·m-1or 4.0 dS·m-1. Leaf osmotic potential of all species in the summer experiment was significantly lower at higher salinity compared with the control. In the fall experiment, leaf osmotic potential in A. millefolium, E. purpurea, and G. aristata at 4 dS·m-1 was lower compared with lower salinity treatment and the control. Leaf osmotic potential in the fall was higher than that of the same species at the same salinity level in the summer experiment, indicating that plants in the fall were less stressed than in the summer. Combined the results from both experiments, the authors concluded that A. millefolium, G. arstata, and S. coccinea had a relatively high salt tolerance (as much as 4 dS·m-1 of irrigation water under greenhouse conditions) among the tested species, whereas A. cana and E. purpurea were not tolerant to salt and should not be irrigated with low-quality water. [ABSTRACT FROM AUTHOR]

The effect of drought on the growth and gas exchange of six bedding plant species--agastache [Agastache urticifolia (Benth.) O. Kuntze 'Honeybee Blue'], dusty miller (Cineraria maritima L. 'Silverdusty'), petunia (Petunia xhybrida 'Wave Purple'), plumbago (Plumbago auriculata Lam. 'Escapade'), ornamental pepper (Capsicum annuum L. 'Black Pearl'), and vinca [Catharanthus roseus (L.) G. Don 'Titan'l--was quantified under greenhouse conditions. Seeds were sown in January and seedlings were grown in the greenhouse until 18 Apr., when two irrigation treatments--drought (D, ≈18% volumetric moisture content at reirrigation) and control (C, ≈25% volumetric moisture content at reirrigation)--were initiated. Leaf net photosynthetic rate (P.), stomatal conductance (gs), and transpiration (E) were determined in response to a range of substrate moisture content (from ≈5% to 30% by volume) and temperature (from 20 °C to 40 °C). Dry weight of agastache, ornamental pepper, and vinca was unaffected by drought, whereas that of other species was reduced. Leaf area of plumbago and height of plumbago and vinca were reduced by drought. As substrate moisture content decreased from 25% to 10%, Pn, E, and gs decreased linearly in all species except petunia and plumbago. Leaf net photosynthetic rate of all species declined as leaf temperature increased from 20 °C to 40 °C. In contrast, E of all species, except petunia, increased as temperature increased. Transpiration rate of petunia increased as temperature increased from 20 °C to 30 °C, and then decreased between 30 °C and 40 °C. Although petunia had the highest Pn among the tested species, its Pn and gs declined more rapidly compared with the other species as temperature increased from 20 °C to 40 °C or as substrate moisture content decreased, indicating that petunia was most sensitive to high temperature and drought. [ABSTRACT FROM AUTHOR]

Use of recycled water to irrigate urban landscapes and nursery plants may be inevitable as fresh water supplies diminish and populations continue to grow in the arid and semiarid southwestern United States. Lupinus havardii Wars. (Big Bend bluebonnet) has potential as a cut flower and Lupinus texensis Hook. (Texas bluebonnet) as a bedding plant, but little information is available on salt tolerance of these species. A greenhouse study was conducted to characterize the growth in response to various salinity levels. Plants were grown in 10-L containers and drip-irrigated with synthesized saline solutions at electrical conductivity levels of 1.6, 3.7, 5.7, 7.6, or 9.4 dS⋅m-1. Although shoot growth of L. texensis was reduced as salinity levels increased, it was visually acceptable (without any visual injury) when irrigated with salinity levels of less than 7.6 dS⋅m-1. All plants survived at 7.6 dS⋅m-1, whereas only 15% did at 9.4 dS⋅m-1. In contrast, L. havardii had leaf injury at 5.7 dS⋅m-1. No plants survived at 9.4 dS⋅m-1, and only 7% plants survived at 7.6 dS⋅m-1. In addition, growth of L. havardii was significantly reduced and plants were shorter at elevated salinity levels. Cut raceme yield of L. havardii decreased at salinity levels greater than 3.7 dS⋅m-1. However, no difference in cut raceme yield was observed between the control and 3.7 dS⋅m-1, although shoot growth was reduced. Overall, L. texensis was more salt-tolerant than L. havardii. [ABSTRACT FROM AUTHOR]

As high-quality water supply becomes limited in many regions of the world, alternative water sources are being used for irrigating urban landscapes. Therefore, salt-tolerant landscape plants are needed. Two greenhouse experiments were conducted to screen the salt tolerance of Zinnia marylandica ('Zahara Coral Rose', 'Zahara Fire', 'Zahara Scarlet', 'Zahara Starlight', 'Zahara White', and 'Zahara Yellow') and Z. maritima 'Solcito'. In Expt. 1, plants were subirrigated with nutrient or saline solutions at electrical conductivity (EC) at 1.4 (base nutrient solution, control), 3.0, 4.2, 6.0, or 8.2 dS·m-1 for 4 weeks, whereas in Expt. 2, plants were surface-irrigated with the same nutrient or saline solutions for 4 weeks. In Expt. 1, all plants, regardless of cultivar, died by the end of the treatment at EC 6.0 and EC 8.2 as a result of high salinity in the root zone. Plants became shorter and more compact as EC of irrigation water increased. Shoot dry weight of all cultivars in EC 4.2 was reduced by 50% to 56% compared with that of the control. Shoot Na+ and Cl- accumulated excessively as salinity increased in the irrigation water, whereas Ca2+, Mg2+, and K+ did not change substantially. In Expt. 2, mortality varied with cultivar and treatment. Similar to Expt. 1, growth reduction resulting from elevated salinity across cultivars was found. Therefore, it is concluded that zinnia cultivars used in this study are sensitive to salinity and should not be planted in areas with high soil salinity or when alternative waters with high salinity may be used for irrigation. [ABSTRACT FROM AUTHOR]

Ornamental chile peppers are popular bedding plants. As high-quality water supply becomes limited in many parts of the world, alternative waters such as municipal reclaimed water is encouraged to be used for landscape irrigation. The purpose of this study was to assess the relative salt tolerance of 10 cultivars of ornamental chile peppers by irrigating the mature plants with saline solutions and germinating seeds in saline substrate in a greenhouse. In the mature plant salt tolerance experiment, plants were irrigated with nutrient solution (no addition of salts, control) or saline solution at electrical conductance (EC) of 4.1 dS⋅m-1 or 8.1 dS⋅m-1 for 8 weeks. Plants in the EC of 4.1 dS⋅m-1 treatment did not have any foliar salt damage regardless of cultivar. At EC of 8.1 dS⋅m-1, 'NuMex Memorial Day' had the most severe foliar salt damage, whereas 'NuMex April Fool's Day', 'NuMex Cinco de Mayo', 'NuMex Thanksgiving', and 'NuMex Twilight' had little or no foliar damage. Shoot dry weight (DW) reduction at EC of 8.1 dS⋅m-1 compared with control was smallest in 'NuMex Thanksgiving' (15%), whereas 'NuMex Memorial Day' had the greatest reduction of 74% followed by 'NuMex Christmas' of 61%. The highest shoot DW reduction in 'NuMex Memorial Day' coincided with lowest visual score, indicating that this cultivar was the least tolerant to salinity. The leaf Na+ and Cl- concentrations increased dramatically with increasing EC of the irrigation water in all cultivars. The highest Na+ concentration of 10.9 mg⋅g-1 DW at EC of 8.1 dS⋅m-1 was observed in 'NuMex Christmas'. The highest Cl- concentration at EC of 8.1 dS⋅m-1 was found in 'NuMex Memorial Day' with 64.8 mg⋅g-1 DW, which was four times higher than the control. In the seedling emergence experiment, seeds of the 10 cultivars were germinated in substrate either moistened with reverse osmosis water (EC ≈0) or saline solution at EC of 17.1 dS⋅m-1 'NuMex Christmas' and 'NuMex Memorial Day' had the lowest relative seedling emergence index, indicating that these two cultivars were the least tolerant to salinity during the seedling emergence stage. 'NuMex Thanksgiving' and 'NuMex Cinco de Mayo' had the highest relative seedling emergence index. Combining the results from both experiments, we concluded that 'NuMex Cinco de Mayo' and 'NuMex Thanksgiving' were the most tolerant cultivars, whereas 'NuMex Christmas' and 'NuMex Memorial Day' were the least tolerant ones. [ABSTRACT FROM AUTHOR]