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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]

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]