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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]

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]