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Do strawberries taste good with salt?
If you follow any Bon Appétit staffer on Instagram, you know when Harry’s Berries are in season. In these parts, the arrival of these ridiculously-delicious berries from a single small farm in California marks the official beginning of summer. They’re our first, precious taste of that real-deal ripe-ripe, and their brief season comes well before we actually get any decent local strawberries in this neck of the woods.
These things are so bursting with flavor that they almost taste fake, more strawberry-y than you could even imagine strawberries could taste. But it can’t be all Harry’s Berries all the time—that’s just not the world we live in. And when we’re facing down a clamshell of less-than, trucked-from-far-away fruit, or even farmers’ market berries that aren’t bursting with flavor, we have a simple trick that will make them taste almost as good.
All you’ve got to do to rescue mediocre berries from their own mediocrity? Add a little sugar and salt! Wash your strawberries, cut them, and hit them with a pinch of salt and a couple good three-finger pinches of granulated sugar, give them a little tossy-toss, and watch them magically start to darken and get extra juicy.
- The additional sugar supplements whatever natural sweetness the strawberries might be lacking, and helps to draw out their juices to form a tasty, ruby red syrup.
- And the salt, which may seem like a wildcard in a sweet preparation, actually does exactly what it does in savory applications—it makes the strawberries taste more, which is especially welcome in a situation when they don’t taste like all that much.
Magically, what were once ho-hum berries start to taste.actually awesome! But folks, it doesn’t stop with strawberries! This same little one-two punch of a flavor enhancer can be applied to any berry that could use a little pick me up. Raspberries. Blackberries.
- Blueberries,
- You name it! It even works with stone fruits like peaches, plums, and nectarines.
- To be quite honest, you’d be hard-pressed to find anything that couldn’t benefit from a little hit of salt and sugar.
- So whenever you can get flavorful, perfectly-ripe berries—Harry’s or otherwise—enjoy them with unadorned and with abandon in whatever strawberry recipe you love.
And all those other times? A little salt ‘n suga will have things tasting juuuuuust fine.
Are strawberries salt sensitive?
Relative Salt Tolerance of Seven Strawberry Cultivars Texas A&M AgriLife Research, El Paso Research and Extension Center, 1380 A&M Circle, El Paso, TX 79927, USA Texas A&M AgriLife Extension, Lubbock Research and Extension Center, 1102 East FM 1294, Lubbock, TX 79403, USA Texas A&M AgriLife Extension, Overton Research and Extension Center, 1710 FM 3053 N, Overton, TX 75684, USA Department of Horticultural Sciences, Texas A&M AgriLife Extension, College Station, 2134 TAMU, TX 77843, USA Author to whom correspondence should be addressed.
Received: 26 August 2015 / Revised: 17 November 2015 / Accepted: 24 November 2015 / Published: 2 December 2015 : Strawberry ( Fragaria × ananassa ) cultivars (“Albion”, “Benicia”, “Camarosa”, “Camino Real”, “Chandler”, “Radiance”, and “San Andreas”) were evaluated for salt tolerance in a greenhouse environment.
Plants were irrigated with a nutrient solution with an electrical conductivity (EC) of 1.1 dS·m −1 (control) or a nutrient solution with the addition of salts (salt solution) with ECs of 2.2, 3.3, or 4.4 dS·m −1 for four months. Salinity reduced plant growth and fruit yield of strawberry; however, the magnitude of reduction varied with cultivar.
- For example, at an EC of 4.4 dS·m −1, “Benicia” and “Chandler” had 39% and 44% less shoot dry weight (DW) respectively, compared with control plants.
- At ECs of 3.3 and 4.4 dS·m −1, “Camino Real” had equal shoot DW, which was about 50% lower than that of the control.
- The fruit yield of “Benicia” and “Camino Real” at 4.4 dS·m −1 was reduced by 56%, while the other salt treatments did not affect their shoot DW or fruit yield.
To distinguish differences among the cultivars with respect to their tolerance to salinity, cluster analysis was performed based on growth parameters and visual quality. The results indicated that “Albion”, “Camarosa”, and “San Andreas” were more salt tolerant, while “Camino Real”, “Benicia”, “Chandler”, and “Radiance” were less salt tolerant.
Strawberry ( Fragaria × ananassa ) is an economically important crop that covered an estimated 58,560 acres in the U.S. in 2013, The commercial production in California and Florida accounted for approximately 82% of total strawberry acreage, Due to its economic importance and the demand for locally-grown berries, growers in other states are starting to produce more strawberries.
In Texas, strawberry is still a minor crop with less than 150 acres representing 0.02 percent of national production, With the large size of Texas, there is great potential for strawberry production to expand into traditionally non-producing regions.
- One of the key production constraints for strawberry is high salinity levels, which are often found in soils in arid and semi-arid regions and irrigation water.
- In recent years, strawberry growers in California have also faced decreased irrigation water quality and increased soil salinity, possibly due to the deterioration of coastal groundwater and low rainfall.
Selecting salt-tolerant strawberry cultivars may be an effective approach for preventing yield and quality reductions. Strawberry is categorized as one of the most salt-sensitive crops with varying degrees of tolerance among cultivars. Salinity causes leaf edge burn, necrosis, nutrient imbalance or specific ion toxicity, reduction in fruit quality and yield, and potential plant death if salinity stress persists or increases.
- In a two-year field study by Saied et al,
- Fruit yield was reduced up to 27% and 64% in the strawberry cultivars “Korona” and “Elsanta”, respectively, when the plants were exposed to NaCl salinity.
- Fruit quality, characterized as taste, aroma, and texture by a consumer-type panel, decreased by more than 24% in “Elsanta”, but differences in “Korona” were not significant.
The reduction in shoot growth between these two strawberry cultivars was also different, up to 90% in “Elsanta” and 40% in “Korona”. Orsini et al, compared the strawberry varieties “Elsanta” and “Elsinore” grown in the presence of 0, 10, 20, and 40 mM NaCl (electrical conductivities (ECs) of 0.45 to 3.9 dS·m −1 ).
- The shoot dry weight and leaf area of both cultivars decreased linearly as the EC of the irrigation solution increased.
- However, the reduction in growth was smaller in “Elsanta” (49%) than in “Elsinore” (90%).
- Many other studies have shown differences in salt tolerance among strawberry cultivars: “Korona” was more tolerant than “Elsanta”, “Toro” was more tolerant than “Douglas”, and “Yalova-104”, “Yalova-15”, “Yalova-416”, and “Arnavutkoy” were more tolerant than “Douglas”, “Dorit”, and “Aliso”,
Turhan and Eris found that “Camarosa” was more tolerant than “Chandler” to NaCl at 8.5, 17.0, or 34.0 mM (equivalent to ECs of 0.8, 1.6, or 3.1 dS·m −1 ). In a field study, Ferreira et al, reported that ‘Albion’ was relatively tolerant among five cultivars based on growth, yield, and the calculated salinity level (EC50) that would reduce fruit yield per hectare by 50%.
- The above studies have indicated variation in salt tolerance among strawberry cultivars and the importance of cultivar selection when soil or water salinity is too high.
- The objective of this study was to determine the relative salt tolerance of seven commercial strawberry cultivars by irrigating plants with a nutrient solution or saline solution at selected levels of salinity.
Gas exchange and leaf sodium (Na), potassium (K), calcium (Ca), and chloride (Cl) accumulation were also determined. On 29 October 2013, plugs of seven strawberry cultivars (“Albion”, “Benicia”, “Camarosa”, “Camino Real”, “Chandler”, “Radiance”, and “San Andreas”) were obtained from the Goodson Farm and Nursery (Damascus, AR, USA).
Plants (~5 leaves, ~15 cm wide) were transplanted into 3.8-L (15.8-cm diameter) black plastic containers filled with LM-40 high porosity growing mix (Canadian sphagnum peat moss 60%, horticultural perlite 40%, limestone, dolomite, wetting agent, micro & macronutrients; Lambert Peat Moss Inc., QC, Canada).
All dead leaves, runners, flowers and/or fruits were trimmed off at transplanting. Plants were grown in a greenhouse with temperature maintained at 26.5 ± 6.1 °C (mean ± standard deviation) during the day and 19.5 ± 6.3 °C at night. The daily light integral (photosynthetically active radiation) was 1.1 ± 3.7 mol·m −2 ·d −1 and relative humidity was 30.3 ± 16.8%.
- Plants were watered with a nutrient solution until salt treatments were initiated.
- The nutrient solution with an EC of 1.1 ± 0.1 dS·m −1 was prepared by adding 1 g·L −1 of 15 N-2.2 P-12.5 K (Scotts Peters 15-5-15; Marysville, OH, USA) to reverse osmosis (RO) water.
- On 25 November 2013, treatments were initiated by irrigating plants with 1 L of nutrient solution (control) or salt solutions to maintain 10% to 20% leaching fraction.
Plants were then irrigated once a week with the nutrient or salt solutions for a total of six times. On 10 January 2014, plants were flushed with 1 L RO water due to high salt accumulation in the root zone (). From 17 January to 31 January, plants were watered with 1 L of nutrient solution.
Plants were then irrigated once a week with the nutrient or salt solutions for another three times (nine times in total). Thereafter, the nutrient solution was applied until the end of the experiment on 11 March 2014. The nutrient solution at an EC of 1.1 ± 0.1 dS·m −1 (control, EC1.1) was prepared as described above.
The salt solution was prepared by adding sodium chloride (NaCl) and calcium chloride (CaCl 2 ) at a 2:1 ratio (molar ratio) to the nutrient solution. Although the composition of salts in salt-affected soil or poor irrigation water varies with location and source of water, NaCl is always dominant among other salts such as CaCl 2,
- All solutions were prepared in 100-L tanks with confirmed ECs of 2.3 ± 0.3 dS·m −1 (EC2.2), 3.3 ± 0.5 dS·m −1 (EC3.3), and 4.5 ± 0.5 dS·m −1 (EC4.4).
- The leachate of the substrate EC was determined periodically using the pour-through method according to Wright,
- Two perpendicular widths (cm), leaf count, and number of crowns of strawberry plants were recorded before initiating treatment (25 November 2013) and at the end of the experiment (11 March 2014).
Mature berries were harvested starting on 7 January 2014, and their number and fresh weight (g) were recorded. The number of mature berries and fresh weight from each harvest were combined for total yield. To determine if salt treatments influenced the sugar content of strawberry fruit, Brix values of four berries were collected on 7 Mar.
For plants in the control and EC4.4 treatments only, using a RF15 Brix refractometer (Extech Instruments Corporation, Nashua, NH, USA). Brix value is a measure of total soluble solids (TSS) in juice, including sugars such as sucrose, fructose, and glucose, Figure 1. Leachate electrical conductivity (EC) from 13 Dec.2013 to 7 Mar.2014.
EC1.1, EC2.2, EC3.3, and EC4.4 represent treatment solutions with ECs of 1.1 dS·m −1, 2.2 dS·m −1, 3.3 dS·m −1, and 4.4 dS·m −1, respectively. Error bars represent the standard error (SE) of five leachate samples. During the experimental period, treatment solutions were applied nine times.
Treatments were initiated on 25 November 2013, and plants were then irrigated weekly with the nutrient or salt solutions for a total of six times. On 10 January, plants were flushed with reverse osmosis (RO) water due to high salt accumulation in the root zone. From 17 Jan. to 31 Jan., all plants were watered with the nutrient solution.
From 7 February to 21 February, all plants were irrigated weekly with the nutrient or salt solutions for another three times. On 28 February and 7 March, plants were irrigated with the nutrient solution. Figure 1. Leachate electrical conductivity (EC) from 13 Dec.2013 to 7 Mar.2014.
EC1.1, EC2.2, EC3.3, and EC4.4 represent treatment solutions with ECs of 1.1 dS·m −1, 2.2 dS·m −1, 3.3 dS·m −1, and 4.4 dS·m −1, respectively. Error bars represent the standard error (SE) of five leachate samples. During the experimental period, treatment solutions were applied nine times. Treatments were initiated on 25 November 2013, and plants were then irrigated weekly with the nutrient or salt solutions for a total of six times.
On 10 January, plants were flushed with reverse osmosis (RO) water due to high salt accumulation in the root zone. From 17 Jan. to 31 Jan., all plants were watered with the nutrient solution. From 7 February to 21 February, all plants were irrigated weekly with the nutrient or salt solutions for another three times. At the end of the experiment, foliar salt damage (leaf edge burn, necrosis, and discoloration) was rated using a visual score of each plant from 0 to 5, where 0 = dead; 1 = over 90% foliar damage; 2 = moderate (50% to 90%) foliar damage; 3 = slight (less than 50%) foliar damage; 4 = good quality with minimal foliar damage; 5 = excellent without any foliar damage. All immature fruits were harvested, and their number and fresh weight (g) were recorded. Upon termination, shoots were severed at the substrate surface. Leaf area (cm 2 ) was determined using an LI-3100C area meter (LI-COR ® Biosciences, Lincoln, NE, USA). Shoot dry weight (DW) was determined after shoots were oven-dried at 65 °C. Leaf transpiration rate (E), stomatal conductance (g s ), and net photosynthesis (P n ) of four plants per treatment by cultivar were measured after the 6th salt treatment and one week before the harvest started (eight weeks after the 1st measurement) using a CIRAS-2 portable photosynthesis system (PP Systems, Amesbury, MA, USA) with an automatic universal PLC6 broad leaf cuvette. Fully expanded, healthy leaves were chosen for measurements. The environmental conditions in the cuvette were controlled at a leaf temperature = 25 °C, photosynthetic photon flux ( PPF ) = 1000 μmol·m −2 ·s −1, and CO 2 concentration = 375 μmol·mol −1, Data were recorded when the environmental conditions and gas exchange parameters in the cuvette became stable. These measurements were taken on sunny days between 1000 HR and 1400 HR, and the plants were well-watered to avoid water stress. Leaf greenness (or relative chlorophyll content) of all plants was measured using a hand-held SPAD chlorophyll meter (Minolta Camera Co., Osaka, Japan) one week before the harvest started. Three healthy, fully-expanded leaves were chosen from each plant. Four plants per treatment by cultivar were selected for mineral analyses. All dried leaves were ground to pass a 40-mesh screen with a stainless Wiley mill (Thomas Scientific, Swedesboro, NJ, USA). About 300 mg of plant leaf tissues were digested using the Environmental Protection Agency method 3051 with 1 mL nitric acid and 4 mL H 2 O 2 using a microwave acceleration reaction system (CEM Corporation; Matthews, NC, USA) for determining alkaline earth metals (Na, K, Ca). The plant tissues were extracted with 2% acetic acid (EM Science, Gibbstown, HJ) for determining anions (Cl) using methods described in Gavlak et al,, Na, K, and Ca in the digested samples were analyzed by inductively coupled plasma-optical emission spectrometry (Perkin-Elmer Optima 4300 DV, Shelton, CT, USA). Chloride was determined using a M926 chloride analyzer (Cole Parmer Instrument Company, Vernon Hills, IL, USA). The experiment followed a split-plot design with salinity as the main plot and cultivar as subplot. Four or five plants were used as replications per salinity level by cultivar. All data were analyzed by two-way ANOVA using PROC GLM. Means separation among cultivars and treatments was conducted using Tukey’s honest significant difference (HSD) test. Relative shoot dry weight for each plant in the salt treatments was calculated as: Similarly, relative percent of perpendicular width, leaf count, leaf area, number of crowns, and cumulative number and fresh weight of mature and immature fruits was calculated. These relative values were used as salt tolerance indexes for hierarchical cluster analysis, A dendrogram of the seven strawberry cultivars was obtained based on the Ward linkage method and squared Euclidian distance of the means of the salt tolerance indexes for nine multivariate parameters including all relative growth data. All statistical analyses were performed using JMP (Version 12, SAS Institute Inc., Cary, NC, USA). The leachate EC data are shown in, From 13 December 2013 to 7 January 2014, leachate EC increased from 2.3 to 2.6 dS·m −1 for plants irrigated with the nutrient solution (control, EC1.1) (). When plants were watered with the saline solution at 2.2, 3.3, or 4.4 dS·m −1, the leachate EC increased from 3.8 to 5.0 dS·m −1, 4.6 to 9.4 dS·m −1, or 5.7 to 9.3 dS·m −1, respectively. From 7 February to 28 February, the leachate EC increased from 2.0 to 5.4 dS·m −1 for EC1.1, 2.6 to 4.8 dS·m −1 for EC2.2, 4.0 to 6.9 dS·m −1 for EC3.3, and 5.0 to 7.5 dS·m −1 for EC4.4, respectively. The final leachate ECs recorded on 12 March were 4.0, 4.1, 5.7, and 8.8 dS·m −1 for EC1.1, EC2.2, EC3.3, and EC4.4, respectively. Salinity in the root zone of a container varies with type of substrate, irrigation frequency (water use of the plants and evaporation), leaching fraction, and salinity of the irrigation water, For most substrates containing materials such as peat, salt accumulation is inevitable. To prevent excessive salt accumulation, the salinity of leachate should be monitored periodically and leaching should be performed as needed. Salt treatment reduced visual quality with variations among cultivars (). The cultivars “Albion” and “San Andreas” had similar visual quality scores (0 = dead; 5 = excellent) across treatments, and their visual scores were higher than “Camino Real” and “Radiance”. For “Benicia”, no differences in visual score were found among treatments, although all scores were below 4.0 even in the control. The lowest visual score (1.8) was observed for “Radiance” at EC4.4. “Benicia” at EC4.4, “Camino Real” at EC3.3 and EC4.4, and “Chandler” at EC4.4 also had visual quality scores lower than 3.0. Foliar salt damages including leaf edge burn, necrosis, and/or discoloration have been observed in other strawberry cultivars, Elevated salinity reduces the growth of strawberry plants, In our experiment, plant width, leaf count, leaf area, and shoot dry weight were significantly different between the salt treatments and among cultivars, but no interactions occurred (). Salt treatment did not affect the perpendicular width in most cultivars with the exception of “Camino Real” and “Chandler”. Compared with the control plants, EC4.4 reduced the perpendicular width of “Camino Real” and “Chandler” by 52% and 67%, respectively. All strawberry cultivars except “Camarosa” and “Camino Real” had similar numbers of leaves across treatments. “Camarosa” plants at EC3.3 and EC4.4 had 52% and 42% fewer leaves, respectively, than the control, while “Camino Real” plants had 65% and 64% fewer leaves, respectively. Salt treatment did not significantly reduce leaf area in individual cultivars except “Camino Real”, although leaf area was reduced at higher salinity levels. “Albion”, “Camarosa”, “Radiance”, and “San Andreas” produced similar shoot biomass in all treatments, but salt treatment at EC4.4 reduced shoot biomass of “Camino Real” and “Chandler” by 49% and 44%, respectively. In addition, when averaged across all cultivars, EC3.3 and EC4.4 decreased shoot biomass by 25% and 38%, respectively. Overall, salt treatment had no effect on the number of crowns ( p = 0.27); however, “Chandler” and “San Andreas” developed more crowns than other cultivars ( p < 0.0001) (data not shown). Table 1. Visual score, plant perpendicular width, number (No.) of leaves, leaf area, and shoot dry weight (DW) of strawberry cultivars irrigated with the nutrient solution (electrical conductivity (EC) =1.1 dS·m −1 ) or salt solutions (EC = 2.2, 3.3, or 4.4 dS·m −1 ) in the greenhouse.
Variety | Treatment (dS·m −1 ) | Visual Score | Width (cm) | No. of Leaves | Leaf Area (cm 2 ) | Shoot DW (g) |
---|---|---|---|---|---|---|
Albion | 1.1 | 4.1 a z | 10.8 a | 9 a | 663 a | 11.9 a |
2.2 | 3.9 a | 11.2 a | 6 a | 565 a | 9.7 a | |
3.3 | 4.0 a | 11.5 a | 5 a | 526 a | 8.6 a | |
4.4 | 3.5 a | 8.3 a | 6 a | 444 a | 6.9 a | |
Mean | 3.9 A y | 10.5 AB | 7 C | 555 BC | 9.4 BC | |
Benicia | 1.1 | 3.6 a | 8.6 a | 8 a | 420 a | 6.8 ab |
2.2 | 3.3 a | 8.2 a | 9 a | 404 a | 7.5 a | |
3.3 | 3.5 a | 9.0 a | 11 a | 357 a | 7.6 a | |
4.4 | 2.9 a | 3.0 a | 4 a | 230 a | 4.1 b | |
Mean | 3.3 ABC | 7.0 B | 8 BC | 349 D | 6.4 CD | |
Camarosa | 1.1 | 4.2 a | 12.4 a | 17 a | 756 a | 11.9 a |
2.2 | 4.2 a | 12.8 a | 12 ab | 704 a | 10.2 a | |
3.3 | 3.6 ab | 11.7 a | 8 b | 646 a | 9.3 a | |
4.4 | 3.0 b | 10.0 a | 10 b | 608 a | 9.1 a | |
Mean | 3.8 AB | 11.8 A | 12 AB | 684 AB | 10.2 AB | |
Camino Real | 1.1 | 3.7 a | 12.9 a | 18 a | 779 a | 14.8 a |
2.2 | 3.8 a | 11.1 ab | 11 ab | 673 ab | 11.4 ab | |
3.3 | 2.6 b | 12.2a | 6 b | 408 b | 7.5 b | |
4.4 | 2.7 b | 6.2 b | 6 b | 443 b | 7.2 b | |
Mean | 3.2 BC | 10.5 AB | 11 ABC | 580 BC | 10.3 AB | |
Chandler | 1.1 | 4.0 a | 11.4 a | 16 a | 854 a | 15.2 a |
2.2 | 4.1 a | 11.9 a | 15 a | 861 a | 16.0 a | |
3.3 | 3.7 a | 9.1 ab | 17 a | 759 a | 11.3 ab | |
4.4 | 2.6 b | 3.8 b | 10 a | 558 a | 8.5 b | |
Mean | 3.6 ABC | 9.2 AB | 15 A | 831 A | 12.8 A | |
Radiance | 1.1 | 3.3 ab | 7.5 a | 6 a | 433 a | 6.1 a |
2.2 | 3.9 a | 11.2 a | 10 a | 507 a | 6.9 a | |
3.3 | 3.1 ab | 8.0 a | 7 a | 381 a | 5.1 a | |
4.4 | 1.8 b | 7.1 a | 5 a | 369 a | 5.3 a | |
Mean | 3.0 C | 8.6 AB | 7 BC | 428 CD | 5.9 D | |
San Andreas | 1.1 | 3.9 a | 11.6 a | 16 a | 814 a | 12.3 a |
2.2 | 4.1 a | 12.3 a | 17 a | 774 a | 13.3 a | |
3.3 | 3.9 a | 12.2 a | 13 a | 645 a | 10.3 a | |
4.4 | 3.8 a | 7.9 a | 11 a | 558 a | 8.5 a | |
Mean | 3.9 A | 11.0 A | 14 A | 691 AB | 11.0 AB | |
Salt treatment | 1.1 | 3.8 a x | 10.9 a | 13 a | 706 a | 11.5 a |
2.2 | 3.9 a | 11.2 a | 11 ab | 653 ab | 10.6 ab | |
3.3 | 3.5 a | 10.5 a | 10 ab | 538 bc | 8.6 bc | |
4.4 | 2.9 b | 6.5 b | 8 b | 457 c | 7.1 c | |
Cultivar | *** w | *** | *** | *** | *** | |
Treatment | *** | *** | *** | *** | *** | |
Cultivar × Treatment | * | NS | NS | NS | NS |
Strawberry yield (number and fresh weight of mature fruits) and potential yield (number and fresh weight of immature fruit) were significantly different among salt treatments and among cultivars, but no interactions were evident (). All strawberry cultivars except “Benicia” and “Camino Real” had similar cumulative numbers of mature berries across treatment levels.
- The number of mature berries of “Benicia” and “Camino Real” at EC4.4 decreased by 56% and 38%, respectively, compared with the control.
- Salt treatment did not significantly reduce the yield of “Albion”, “Camarosa”, “Chandler”, “Radiance”, and “San Andreas”, although there was a lower total mature fruit fresh weight at EC4.4.
The fresh weight of mature fruit of “Benicia” and “Camino Real” at EC4.4 was reduced by 57% and 56%, respectively, compared with the control. Salt treatment had no effect on immature fruit number. The fresh weight of immature berries of “San Andreas” at EC4.4 was reduced by 58%.
- The other cultivars had similar fresh weights among treatments.
- These results further demonstrate that salinity negatively impacted the yield of immature fruit strawberries, but the level of yield reduction varied with cultivar.
- Similar results on strawberry yield reduction with increasing salinity levels were reported by others,
Table 2. Cumulative number of mature berries, cumulative fresh weight (FW) of mature fruit, number of immature fruit, and FW of immature fruit of strawberry cultivars irrigated with nutrient solution (electrical conductivity (EC) = 1.1 dS·m −1 ) or salt solutions (EC = 2.2, 3.3, or 4.4 dS·m −1 ) in the greenhouse.
Variety | Treatment (dS·m −1 ) | No. of Mature Fruits | FW of Mature Fruits (g) | No. of Immature Fruits | FW of Immature Fruits (g) |
---|---|---|---|---|---|
Albion | 1.1 | 7 a z | 103.5 a | 5 a | 14.5 ab |
2.2 | 7 a | 105.2 a | 6 a | 23.9 a | |
3.3 | 6 a | 89.4 a | 5 a | 12.1 ab | |
4.4 | 7 a | 81.8 a | 4 a | 9.8 b | |
Mean | 7 CD y | 95.2 A | 5.1 C | 14.9 ABC | |
Benicia | 1.1 | 11 a | 130.4 a | 5 a | 10.3 a |
2.2 | 7ab | 82.7 ab | 4 a | 9.4 a | |
3.3 | 8 ab | 94.4 ab | 5 a | 14.8 a | |
4.4 | 5 b | 56.4 b | 3 a | 8.3 a | |
Mean | 8 CD | 88.6 AB | 4.1 C | 10.5 C | |
Camarosa | 1.1 | 11 a | 122.8 a | 7 a | 10.6 a |
2.2 | 12 a | 126.3 a | 6 a | 9.0 a | |
3.3 | 12 a | 103.1 a | 5 a | 7.0 a | |
4.4 | 12 a | 100.9 a | 5 a | 7.3 a | |
Mean | 12 A | 114.5 A | 5.7 C | 8.6 C | |
Camino Real | 1.1 | 8 a | 138.3 a | 6 a | 17.6 a |
2.2 | 6 ab | 90.7 ab | 8 a | 21.0 a | |
3.3 | 7 ab | 112.2 ab | 4 a | 10.5 a | |
4.4 | 5 b | 60.6 b | 7 a | 18.2 a | |
Mean | 7 CD | 100.3 A | 6.2 BC | 16.7 ABC | |
Chandler | 1.1 | 11 a | 135.0 a | 10 a | 27.5 a |
2.2 | 9 a | 127.2 a | 12 a | 28.7 a | |
3.3 | 9 a | 112.0 a | 9 a | 21.1 a | |
4.4 | 7 a | 69.5 a | 9 a | 16.0 a | |
Mean | 9 BC | 112.3 A | 9.8 A | 23.1 A | |
Radiance | 1.1 | 13 a | 128.4 a | 7 a | 12.7 a |
2.2 | 11 a | 124.7 a | 7 a | 17.6 a | |
3.3 | 12 a | 119.0 a | 6 a | 11.3 a | |
4.4 | 9 a | 90.4 a | 6 a | 10.5 a | |
Mean | 11 AB | 117.8 A | 6.3 BC | 13.3 BC | |
San Andreas | 1.1 | 6 a | 66.8 a | 10 a | 31.7 a |
2.2 | 6 a | 70.1 a | 9 a | 18.7 ab | |
3.3 | 5 a | 54.4 a | 10 a | 17.8 ab | |
4.4 | 5 a | 41.0 a | 6 a | 13.3 b | |
Mean | 5 D | 57.6 B | 8.6 AB | 19.8 AB | |
Salt treatment | 1.1 | 10 a x | 118.8 a | 7 a | 17.8 a |
2.2 | 8 ab | 103.5 a | 7 a | 17.3 a | |
3.3 | 8 ab | 97.3 a | 6 a | 13.8 a | |
4.4 | 7 b | 69.0 b | 6 a | 12.1 a | |
Cultivar | *** w | *** | * | ** | |
Treatment | *** | *** | *** | *** | |
Cultivar × Treatment | NS | NS | NS | NS |
Fruit Brix values for plants at EC4.4 were similar to those in the control treatment ( p = 0.11), but significantly different among cultivars ( p = 0.02) (data not shown). In addition, there was no interaction effect between treatment and cultivar ( p = 0.95).
Our results indicated that salt treatment did not impact the sweetness of harvested berries. Ferreira et al, also found similar results. However, Saied et al, reported that Brix values for the strawberry cultivars “Korona” and “Elsanta” decreased significantly with salinity. The differences may be a result of the different salt concentrations used in these studies.
Hierarchical cluster analysis of the seven strawberry cultivars was conducted using multivariate parameters including all relative growth data, The dendrogram showed three distinguishable clusters (). “Albion”, “Camarosa”, and “San Andreas” were clustered together and were determined to be the most salt tolerant group.
- Camino Real” was separated from all others and considered to have moderate salt tolerance.
- Benicia”, “Chandler”, and “Radiance” were classified as salt sensitive.
- These results agree with previous reports on the salt tolerance of strawberry cultivars.
- Gulen et al,
- Found that “Camarosa” was more tolerant than “Chandler” to NaCl treatment at 8.5, 17.0, or 34.0 mM.
Ferreira et al. reported that in a field study, “Albion” was relatively tolerant among five cultivars based on growth, yield, and the calculated EC50 (the salinity level that would reduce fruit yield per hectare by 50%). Figure 2. Hierarchical cluster analysis of seven strawberry cultivars using multivariate parameters including all relative growth data. Gas exchange recorded after the strawberry cultivars were watered six times with the salt solutions showed that salt treatment had no effect on P n ( p = 0.47; data not shown). However, P n differed among cultivars ( p = 0.003). “Albion” had the highest P n of 14.7 μmol·m −2 ·s −1, while “San Andreas” had the lowest P n of 10.6 μmol·m −2 ·s −1,
- Gas exchange was measured again one week prior to the final harvest (eight weeks after the first measurement).
- Leaf, stomatal g s, and P n were different among treatments ().
- Salt treatment generally decreased the overall transpiration rate or stomatal conductance across all cultivars at EC4.4 or EC3.3, respectively, although individual cultivars did not show salt effects on P n,
As shown in, all three parameters, P n, g s, and E were reduced at EC3.3 and EC4.4 across all cultivars. Salt treatment did not affect the overall cultivar chlorophyll leaf content, but the SPAD meter readings varied among cultivars (). When averaged across all salt treatments, “San Andreas” and “Camino Real” had higher leaf chlorophyll content with SPAD readings of 49.2 and 48.3, respectively, while “Camarosa” and “Chandler” were lower at 45.6 and 41.9, respectively.
Variety | Treatment | E (mmol·m −2 ·s −1 ) | g s (mmol·m −2 ·s −1 ) | P n (μmol·m −2 ·s −1 ) | SPAD |
---|---|---|---|---|---|
Albion | 1.1 | 7.9 a z | 422.6 a | 16.2 a | 46.3 a |
2.2 | 7.1 a | 396.3 a | 15.6 a | 46.6 a | |
3.3 | 6.3 a | 306.4 a | 13.2 a | 45.5 a | |
4.4 | 6.1 a | 323.8 a | 13.9 a | 47.2 a | |
Mean | 6.9 A y | 360.5 AB | 14.7 A | 46.4 BC | |
Benicia | 1.1 | 7.8 a | 478.0 a | 16.0 a | 43.1 a |
2.2 | 7.1 a | 391.6 a | 15.2 a | 47.4 a | |
3.3 | 7.3 a | 424.8 a | 15.6 a | 46.6 a | |
4.4 | 6.3 a | 299.4 a | 13.4 a | 47.0 a | |
Mean | 7.1 A | 392.6 A | 14.9 A | 46.2 BC | |
Camarosa | 1.1 | 7.3 a | 369.0 a | 14.7 ab | 45.1 a |
2.2 | 7.6 a | 366.6 a | 15.8 a | 44.2 a | |
3.3 | 6.4 a | 269.8 a | 11.4 b | 46.2 a | |
4.4 | 6.2 a | 314.3 a | 12.2 ab | 47.2 a | |
Mean | 6.9 A | 334.1 AB | 13.7 A | 45.6 C | |
Camino Real | 1.1 | 7.9 a | 369.6 a | 14.0 ab | 49.4 a |
2.2 | 7.3 a | 420.5 a | 17.0 a | 49.4 a | |
3.3 | 6.6 a | 304.8 a | 12.4 b | 47.1 a | |
4.4 | 7.4 a | 393.8 a | 15.8 ab | 47.3 a | |
Mean | 7.3 A | 373.2 AB | 14.8 A | 48.3 AB | |
Chandler | 1.1 | 7.1 a | 394.0 a | 15.8 ab | 43.2 a |
2.2 | 7.1 a | 407.8 a | 16.5 a | 44.1 a | |
3.3 | 6.1 a | 306.8 a | 11.3 b | 40.5 a | |
4.4 | 6.2 a | 359.0 a | 15.4 ab | 40.0 a | |
Mean | 6.6 A | 365.1 AB | 14.6 A | 41.9 D | |
Radiance | 1.1 | 7.5 ab | 331.8 ab | 14.1 ab | 42.6 a |
2.2 | 8.1 a | 375.0 a | 14.9 a | 48.9 a | |
3.3 | 5.7 b | 272.8 ab | 11.9 ab | 43.6 a | |
4.4 | 5.9 ab | 234.3 b | 9.4 b | 45.6 a | |
Mean | 6.8 A | 305.7 AB | 12.7 A | 45.8 BC | |
San Andreas | 1.1 | 7.1 a | 325.0 a | 13.7 ab | 48.5 ab |
2.2 | 7.3 a | 356.6 a | 15.2 a | 52.2 a | |
3.3 | 6.2 a | 284.8 a | 13.0 ab | 50.0 ab | |
4.4 | 6.0 a | 245.2 a | 11.1 b | 47.2 b | |
Mean | 6.6 A | 301.7 B | 13.2 A | 49.2 A | |
Salt treatment | 1.1 | 7.5 a x | 384.8 a | 14.9 a | 45.8 a |
2.2 | 7.4 a | 385.8 a | 15.7 a | 47.4 a | |
3.3 | 6.3 b | 307.8 b | 12.6 b | 45.5 a | |
4.4 | 6.3 b | 310.7 b | 13.1 b | 46.1 a | |
Cultivar | NS w | *** | * | *** | |
Treatment | *** | *** | *** | NS | |
Cultivar × Treatment | NS | NS | NS | * |
Leaf Na and Ca concentrations were significantly different among salt treatments and cultivars, but there were no interactions (). Compared with the plants in the control treatment, leaf Na concentrations of “Camarosa”, “Chandler”, and “San Andreas” at EC4.4 increased by 323%, 423%, and 90%, respectively, while those of “Camino Real” and “Chandler” at EC3.3 increased by 199% and 156%, respectively.
The other salt treatments did not affect the leaf Na concentration of “Camarosa”, “Camino Real”, “Chandler”, and “San Andreas”. The highest Na concentration (2.21 mg·g −1 DW) was measured in “Radiance” at EC4.4. Turhan and Eris reported that NaCl treatments at 8.5, 17.0, or 34.0 mM increased the Na concentration in the leaf tissue of “Camarosa” and “Chandler” with a sharp increase in “Chandler”.
Leaf Ca concentrations in the cultivars “Albion”, “Benicia”, and “Camarosa” were not statistically different among treatments (). Compared with control plants, the leaf Ca concentration of “Chandler”, “Radiance”, and “San Andreas” at EC3.3 increased by 25%, 27%, and 30%, respectively, while that of “Camino Real”, “Chandler”, and “San Andreas” at EC4.4 increased by 31%, 39%, and 33%, respectively.
- The highest Ca concentrations (25.84 mg·g −1 DW) were measured in “Radiance” at EC3.3.
- In contrast, Keutgen and Pawelzik reported that leaf Ca concentrations for “Korona” and “Elsanta” were not affected when they were exposed to NaCl at 40 and 80 mmol·L −1,
- Leaf Cl concentrations were significantly affected by the salt treatments and cultivars and their interaction ().
Applying salt treatments increased the leaf Cl concentration of all strawberry cultivars. The three cultivars with relatively low leaf Cl concentrations (below 15 mg·g −1 ) at EC4.4 were “San Andreas”, “Albion”, and “Camarosa”. Coincidentally, these three cultivars had visual scores above 3.0 and were clustered together in the relatively tolerant group, while the other four cultivars had visual scores below 3.0 with leaf Cl concentrations at EC4.4 above 15.0 mg·g −1,
- The highest Cl concentration (19.77 mg·g −1 DW) was found in “Chandler” at EC4.4.
- Turhan and Eris similarly reported that the Cl concentration in the leaves of “Camarosa” and “Chandler” progressively increased with increasing NaCl concentrations from 8.5 to 34.0 mM.
- Na exclusion and tolerance of tissue to accumulated Cl are two mechanisms of plant adaptation to salinity,
Strawberry is considered an Na excluder and has an extremely low chlorine requirement, In our study, all cultivars had relatively low leaf Na concentrations, generally lower than 1.5 mg·g −1 dry mass. However, leaf Cl concentrations at EC4.4 were much higher, especially for “Benicia”, “Camino Real”, “Chandler”, and “Radiance”.
- Similar results were reported by Saied et al,
- Who conducted a two-year field study with “Elsanta” and “Korona” under salinity levels of 0.3, 2.6, and 5.1 dS·m −1,
- In their study, Na concentrations below 3 mg·g −1 were reported, while Cl concentrations increased up to 70 mg·g −1 in “Korona” and 80 mg·g −1 in “Elsanta” plants.
They also reported that “Korona” retained most of its Cl in the roots and crowns, while the highest concentration of Cl was detected in “Elsanta” petioles. Strawberry plants are sensitive to high Cl levels and a leaf Cl concentration higher than 0.5% is associated with leaf necrosis and yield reduction in many cultivars,
Variety | Treatment | Ion Concentration (mg·g −1 ) | |||
---|---|---|---|---|---|
Na | Ca | Cl | K | ||
Albion | 1.1 | 0.56 a z | 17.29 a | 3.63 c | 27.03 a |
2.2 | 0.82 a | 22.47 a | 8.58 b | 23.46 ab | |
3.3 | 0.66 a | 22.08 a | 10.58 ab | 23.34 ab | |
4.4 | 0.92 a | 21.37 a | 13.80 a | 21.16 b | |
Mean | 0.75 A y | 20.80 A | 9.14 A | 23.75 A | |
Benicia | 1.1 | 0.73 a | 18.52 a | 4.73 d | 23.79 a |
2.2 | 0.94 a | 18.49 a | 8.60 c | 21.95 ab | |
3.3 | 1.41 a | 18.64 a | 11.58 b | 21.28 ab | |
4.4 | 1.55 a | 21.58 a | 16.08 a | 19.46 b | |
Mean | 1.16 A | 19.31 AB | 10.24 A | 21.62 AB | |
Camarosa | 1.1 | 0.43 b | 16.09 a | 3.10 c | 22.36 a |
2.2 | 0.86 ab | 18.39 a | 9.20 b | 21.49 ab | |
3.3 | 1.06 ab | 21.98 a | 14.30 a | 19.29 b | |
4.4 | 1.35 a | 21.86 a | 13.43 a | 18.64 b | |
Mean | 0.89 A | 19.25 AB | 9.78 A | 20.44 B | |
Camino Real | 1.1 | 0.61 b | 17.08 b | 4.00 c | 26.36 a |
2.2 | 0.93 b | 17.66 ab | 9.85 b | 23.95 ab | |
3.3 | 1.83 a | 22.30 ab | 16.38 a | 21.26 b | |
4.4 | 1.13 b | 22.42 a | 17.55 a | 20.54 b | |
Mean | 1.13 A | 19.86 A | 11.94 A | 23.03 AB | |
Chandler | 1.1 | 0.40 c | 16.65 b | 3.63 d | 24.33 a |
2.2 | 0.62 bc | 18.42 ab | 9.48 c | 21.91 b | |
3.3 | 1.02 ab | 20.74 a | 13.00 b | 20.88 b | |
4.4 | 1.31 a | 21.05 a | 19.77 a | 21.82 b | |
Mean | 0.80 A | 19.10 AB | 10.91 A | 22.24 AB | |
Radiance | 1.1 | 0.83 a | 21.27 b | 5.38 b | 25.67 a |
2.2 | 1.11 a | 19.53 b | 9.70 b | 24.53 a | |
3.3 | 1.43 a | 25.84 a | 9.37 b | 21.09 a | |
4.4 | 2.21 a | 23.96 ab | 17.23 a | 21.29 a | |
Mean | 1.27 A | 22.20 A | 10.00 A | 23.41 A | |
San Andreas | 1.1 | 0.58 b | 13.85 b | 2.98 c | 25.80 a |
2.2 | 0.80 ab | 15.31 ab | 7.83 b | 24.75 a | |
3.3 | 0.82 ab | 17.94 a | 11.33 a | 22.80 ab | |
4.4 | 1.11 a | 18.37 a | 13.78 a | 20.13 b | |
Mean | 0.83 A | 16.37 B | 8.98 A | 23.37 A | |
Salt treatment | 1.1 | 0.59 b x | 17.25 b | 3.92 d | 25.05 a |
2.2 | 0.87 b | 18.61 b | 9.03 c | 23.15 b | |
3.3 | 1.18 a | 21.16 a | 12.47 b | 21.42 c | |
4.4 | 1.30 a | 21.32 a | 15.84 a | 20.37 c | |
Cultivar | *** w | *** | *** | *** | |
Treatment | *** | *** | *** | *** | |
Cultivar × Treatment | NS | NS | * | NS |
Potassium (K) plays an important role in turgor-pressure-driven solute transport in the xylem and water balance of plants, Plants exposed to NaCl inevitably accumulate high amounts of Na, which subsequently interferes with K uptake, causing a reduction in K content,
In our experiment, leaf K concentrations decreased significantly with increasing EC levels in all cultivars except “Radiance” (). Compared with the control plants, the leaf K concentration at EC4.4 for all strawberry cultivars decreased by 10% to 26%, except for Radiance. However, K concentrations for “Camarosa”, “Camino Real”, and “Chandler” were reduced by 14% to 19% when irrigated with a salt solution of only EC 3.3 dS·m −1,
Interestingly, a salt solution at an EC of only 2.2 dS·m −1 decreased the leaf K concentration of “Chandler” by 10%. Turhan and Eris reported that the potassium content decreased in the aerial part of “Camarosa” plants with increasing NaCl levels from 8.5 to 34.0 mM, but with “Chandler”, a solution of 8.5 mM NaCl increased the K content compared with the control.
Eutgen and Pawelzik reported that “Korona” strawberry also had a significant increase in the K content of the leaves. These results suggest that the efficiency of K uptake or the ability of strawberry adaptation to increasing levels of salinity is cultivar dependent. The results of this study further indicated that variations in tolerance to salinity exists among cultivars.
Growers who are considering growing strawberries in soils with relatively high salinity levels or who will be irrigating with saline water should consider selecting cultivars that have demonstrated salt tolerance. When produced under optimal conditions, strawberries have a high value of return; however, costs of production are also high and the increased salinity levels found in many regions like Texas could experience reduced yields, berry quality and, subsequently, grower profitability.
Similar research is needed on additional selected cultivars that are being considered for strawberry production in Texas and other regions where high salt levels can potentially reduce crop performance. The plant growth and fruit yield across all strawberry cultivars were reduced by the increased salinity of the irrigation water in this study, but the level of reduction varied with cultivar and the level of salinity.
The salt solution at an EC of 4.4 dS·m −1 significantly reduced the shoot DW of “Camino Real” and “Chandler” as well as the fruit yield of “Benicia” and “Camino Real”. The salt solution at an EC of 3.3 dS·m −1 significantly reduced the shoot DW of “Camino Real”, but not the other cultivars.
- Three distinguishable strawberry groups were obtained using cluster analysis, which showed that “Albion”, “Camarosa”, and “San Andreas” were the most salt tolerant cultivars, while “Benicia”, “Chandler”, and “Radiance” were the least tolerant.
- Although “Camino Real” was classified as moderately salt tolerant by the cluster analysis, its visual scores were lower and leaf Cl concentrations were higher, and thus it probably should be grouped as less tolerant.
“Chandler” is considered one of the industry standards for producers in Texas, but its susceptibility to salinity may reduce its widespread use as production acreage expands. “Camarosa” is similar to “Chandler” in overall production, and may be a better choice due to higher salt tolerance.
This research was partially supported by a grant from the National Strawberry Sustainability Initiative with funding provided by the Walmart Foundation and administered by the University of Arkansas and U.S. Department of Agriculture National Institute of Food and Agriculture Hatch project TEX090450.
The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies. This work was a product of the combined effort of all of the authors. All authors conceptualized and designed the study.
Youping Sun performed the experiments, collected and analyzed the data, and wrote the manuscript with assistance from all other authors, mainly Genhua Niu. Joseph Masabni, Russ Wallace, and Mengmeng Gu provided technical advice and assistance when the study was conducted, and revised and improved the manuscript.
The authors declare no conflict of interest.
USDA, National Agricultural Statistics Service. Noncitrus Fruits and Nuts 2013 Summary ; U.S. Department of Agriculture: Washington, DC, USA, 2014. Wallace, R.W.; Stein, L. Strawberry production in Texas. In Production Guide for Texas-Grown Strawberries ; Wallace, R.W., Anciso, J., Eds.; Texas A&M AgriLife Extension: College Station, TX, USA; Available online: (accessed on 25 May 2015).Wallace, R.W.; Webb, C.J. Strawberries grown under protective cultivation on the Texas High Plains.J. Amer. Pomol. Soc.2013, 67, 7–10. Saied, A.S.; Keutgen, A.J.; Noga, G. The influence of NaCl salinity on growth, yield and fruit quality of strawberry cvs. “Elsanta” and “Korona”. Sci. Hortic.2005, 103, 289–303. Orsini, F.; Alnayef, M.; Bona, S.; Maggio, A.; Gianquinto, G. Low stomatal density and reduced transpiration facilitate strawberry adaptation to salinity. Environ. Exp. Bot.2012, 81, 1–10. Keutgen, A.J.; Pawelzik, E. Quality and nutritional value of strawberry fruit under long term salt stress. Food Chem.2009, 107, 1413–1420. Martinez Barroso, M.C.; Alvarez, C.E. Toxicity symptoms and tolerance of strawberry to salinity in the irrigation water. Sci. Hortic.1997, 71, 177–188. Kepenek, K.; Koyuncu, F. Studies on the salt tolerance of some strawberry cultivars under glasshouse. Acta Hortic.2002, 573, 297–304. Turhan, E.; Eris, A. Changes of growth, amino acids, and ionic composition in strawberry plants under salt stress conditions. Commun. Soil Sci. Plant Anal.2009, 40, 3308–3322. Ferreira, J.F.S.; Liu, X.; Suarez, D.L. Salinity tolerance of five commercial cultivars of strawberry ( Fragaria × ananass a Duch.). In Proceedings of the 3rd International Salinity Forum, Riverside Convention Center, CA, USA, 16–18 June 2014; pp.170–171.Wright, R.D. The pour-through nutrient extraction procedure. Hortscience 1986, 21, 227–229. Harrill, R. Using a Refractometer to Test the Quality of Fruits & Vegetables ; Pineknoll Publishing: Keedysville, MD, USA, 1998. Gavlak, R.G.; Horneck, D.A.; Miller, R.O. Plant, Soil, and Water Reference Methods for the Western Region ; Western Regional Extension Publication (WREP): Corvallis, OR, USA, 1994; Volume 125. Zeng, L.; Shannon, M.C.; Grieve, C.M. Evaluation of salt tolerance in rice genotypes by multiples agronomic parameters. Euphytica 2002, 127, 235–245. Niu, G.; Cabrera, R. Growth and physiological responses of landscape plants to saline water irrigation: A review. HortScience 2010, 45, 1605–1609. Kaya, C.; Higgs, D.; Saltali, K.; Gezerel, O. Response of strawberry growth at high salinity and alkalinity to supplementary potassium.J. Plant Nutr.2002, 25, 1415–1427. Gulen, H.; Turhan, E.; Eris, A. Changes in peroxidase activities and soluble proteins in strawberry varieties under salt stress. Acta Physiolagiae Plant.2006, 28, 109–116. Turhan, E.; Eris, A. Changes of micronutrients, dry weight, and chlorophyll contents in strawberry plants under salt stress conditions. Commun. Soil Sci. Plant Anal.2005, 36, 1021–1028. Munns, R.; Tester, M. Mechanisms of salinity tolerance. Annu. Rev. Plant Biol.2008, 59, 651–681. Ulrich, A.; Mostafa, M.A.E.; Allen, W.W. Strawberry Deficiency Symptoms: A Visual and Plant Analysis Guide to Fertilization ; Agricultural Experiment Station, Division of Agriculture and Natural Resources, University of California: Berkeley, CA, USA, 1980. Marschner, H. Mineral Nutrition of Higher Plants, 2nd ed.; Academic Press: London, UK, 1995. Hasegawa, P.M.; Bressan, R.A.; Zhu, J.K.; Bohnert, H.J. Plant cellular and molecular responses to salinity. Annu. Rev. Plant Physiol. Plant Mol. Biol.2000, 51, 463–499.
© 2015 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/). Sun, Y.; Niu, G.; Wallace, R.; Masabni, J.; Gu, M.
- Relative Salt Tolerance of Seven Strawberry Cultivars.
- Horticulturae 2015, 1, 27-43.
- Https://doi.org/10.3390/horticulturae1010027 AMA Style Sun Y, Niu G, Wallace R, Masabni J, Gu M.
- Relative Salt Tolerance of Seven Strawberry Cultivars.
- Horticulturae,2015; 1(1):27-43.
- Https://doi.org/10.3390/horticulturae1010027 Chicago/Turabian Style Sun, Youping, Genhua Niu, Russ Wallace, Joseph Masabni, and Mengmeng Gu.2015.
“Relative Salt Tolerance of Seven Strawberry Cultivars” Horticulturae 1, no.1: 27-43. https://doi.org/10.3390/horticulturae1010027 For more information on the journal statistics, click, : Relative Salt Tolerance of Seven Strawberry Cultivars
Does salt enhance fruit?
A long-standing culinary practice is to sprinkle a little salt on fruits such as watermelon, tomatoes or cantaloupe to make them taste sweeter.
Why do people add salt to fruit?
Add a dash, pinch or sprinkle to your fruit – Using salt on both ripe and unripened fruit should be your new kitchen trick. Though there’s almost nothing better than perfectly ripened fruit, adding a pinch of salt actually amplifies the fruit’s natural flavor—making it essentially a more enhanced version of itself—while sprinkling a pinch of salt to unripened fruit can actually reduce its bitterness.
What fruit is better with salt?
Mango, cantaloupe, grapefruit, pineapple, watermelon—it does wonders with so many fruits. I hate eating raw fruit. I know that eating fruit in its natural state, packed with fiber and nutrients, is good for you, but I don’t like the feeling of raw fruit scraping down my throat.
Biting into an apple makes me cringe. Sometimes I’ll munch on a handful of grapes, or slice up some strawberries for a yogurt bowl, but generally I avoid it. Give it to me roasted, give it to me in a compote ; just don’t feed me raw fruit—unless you’ve put salt on it, At this year’s Atlanta Food and Wine Festival, I took class taught by three pastry chefs who demonstrated how to apply savory flavors to sweet ingredients.
Two of them made desserts, but Jen Yee, executive pastry chef of Atlanta’sHoleman & Finch Public House and C. Ellet’s, served us sliced raw peaches with a healthy sprinkling of sea salt. “I just wanted to really bring it right down to the bare bones. Just take something with and without salt, just to sort of illustrate what salt can do,” Yee says.
We tasted a raw peach and then tasted the peaches that had been sprinkled with sea salt. The difference was remarkable: the peach with the sea salt was sweeter but not cloying, more floral, and even juicier. I was hooked. “When you first bite into a peach the first thing you’re hit with is how sweet is is, right?” Yee says.
“But when you eat a peach that has a little bit of salt on it, that sweet hit is slightly delayed because first you’re getting this saline reaction happening in your mouth, and then it’s like the salivary glands are activated and getting juicy, and then you get hit with that sweetness at the end.” Guy Crosby is the former science editor for America’s Test Kitchen and goes by the moniker of the Cooking Science Guy.
He says that the reason why salt makes fruit taste sweeter is a bit of a mystery. “The exact reason for it, the nature for what is happening on a molecular level, is not clearly understood. Salt in some way is affecting the sweet taste receptor for sugar and presumably is enhancing the sweet taste of the sugar,” he says.
One study, conducted by Monell Chemical Senses Center, found that our taste cells have additional sugar detectors than previously thought, and that one of them directs sugar to a sweet-taste cell when sodium is detected. Seasoning fruit with salt is nothing new.
In Mexico, you’ll often find mango and citrus sprinkled with a blend of salt and chile powder. In the Philippines, mango is served with shrimp paste, a fermented, salty condiment. And some Southerners like to put salt on their watermelon. You can put salt on any fruit, but your mileage may vary with the results.
As Crosby explains, “I would say that the fruits that tend to contain more of these sugars, either sucrose or glucose or fructose, the greater the enhancement you’re going to perceive of the sweetness due to the salt.” Salt will make the sweetest fruits (i.e.
cherries and strawberries) even sweeter, but if you’re more interested in balancing the flavors, stick to fruits with more nuance like cantaloupe, grapefruit, pineapple, and watermelon. It’s easy to make a salty sweet fruit snack. Start with ripe fruit, and simply slice your fruit the way you normally would—I found peaches do better when sliced thin, watermelon does great in wedges—and give the slices a hearty sprinkle of salt.
You can use any salt, but I prefer to use large flaked sea salt for the bit of crunch it provides (and it’s aesthetically pleasing). Let it sit for about 10 minutes to let the salt work its magic.
Can I eat banana with salt?
Here’s what experts say when it comes to bananas for controlling diarrhea. (Source: Getty Images/Thinkstock) Blame it on the changing weather, food habits or even exertion, loose motions or diarrhea can happen to anyone. It is, in fact, one of the most common digestive disorders along with constipation,
While there are several medicines available to instantly control loose motions, some people swear by home remedies like eating a banana to control loose stools and also make the body feel stronger. But should you be having bananas? A commonly available fruit, bananas are rich in fibre (like cellulose hemicellulose) which help add bulk to the stool and improve bowel movement,
In fact, it is one of the most trusted traditional remedies for loose motions. Dr Mahesh Gupta, senior consultant, gastroenterologist, Dharamshila Narayana Superspeciality Hospital says, “Basically, bananas are high in potassium which helps to get the digestion process back to normal. Stomach troubling you? Count on a banana. Here’s why. (Source: Getty Images/Thinkstock) Also, bananas, which are a low residue food, help deal with the weakness and dehydration that can come with losing too much fluid from the body. “Banana provides calories in the form of carbohydrate that gives instant energy to cope with the weakness due to loose motion,” said Seema Singh, chief clinical nutritionist, Fortis Vasant Kunj, New Delhi,
- Concurred Zoya Fakhi, nutritionist, Bhatia Hospital.
- Mumbai and said, “100 grams gives 116-kilo calorie, hence the energy lost and the exertion caused due to loose motions can be replenished by bananas.” Studies have shown pectin, a type of fibre found in raw banana, absorbs excess water from intestines and forms the stools.
ALSO READ | Should you consume the banana peel? Find out here How to have? Consuming bananas with a little curd is a traditional combination which works wonders, remarked Singh. Eating bananas with salt provides sodium and potassium, electrolytes which deplete if you have diarrhea, said Singh.
“It can be consumed twice or thrice depending on the frequency of loose motions. In case the individual is unable to consume normal foods, they can consume banana in combination with curd and rice or as a plain fruit depending on their preference,” explained Fakhi. However, Dr Gupta has a word of caution.
“One has to make sure she/he is taking ripe bananas and not the raw/green ones which can potentially have a reverse effect during loose motions or diarrhea,” he asserted. Don’t forget to drink enough fluid, especially water, to stay hydrated, suggest the nutritionists.
Why not to eat table salt?
Sodium and Health – In most people, the kidneys have trouble keeping up with excess sodium in the blood. As sodium accumulates, the body holds onto water to dilute the sodium. This increases both the amount of fluid surrounding cells and the volume of blood in the bloodstream.
Increased blood volume means more work for the heart and more pressure on blood vessels. Over time, the extra work and pressure can stiffen blood vessels, leading to high blood pressure, heart attack, and stroke. It can also lead to heart failure. There is some evidence that too much salt can damage the heart, aorta, and kidneys without increasing blood pressure, and that it may be bad for bones, too.
Learn more about the health risks and disease related to salt and sodium: Cardiovascular disease After conducting a review on sodium research, the Institute of Medicine concluded that reducing sodium intake lowers blood pressure, but evidence of a decreased risk of cardiovascular diseases (CVD) is inconclusive.
- It is clear, however, that high blood pressure is a leading cause of CVD.
- It accounts for two-thirds of all strokes and half of heart disease.
- In China, high blood pressure is the leading cause of preventable death, responsible for more than one million deaths a year.
- There may be a genetic component to salt intake, as people respond differently to lower sodium intakes.
Those who are “salt-sensitive” experience the greatest blood pressure reductions after following a reduced sodium diet. Those who are “salt-resistant” do not experience these changes even with significant increases in sodium intake. Studies have found that women more than men, people older than 50 years, African-Americans, and those with a higher starting blood pressure respond the greatest to reduced sodium intake.
- However, there is not enough evidence to make strong conclusions about specific groups who may be salt-resistant; the overall evidence supports a benefit of limiting sodium intake for everyone, even though the optimal target amount is not clear.
- Observational and clinical research has found that higher sodium intakes are associated with cardiovascular diseases and related deaths.
The following are key studies:
- Intersalt: Researchers measured the amount of sodium excreted over a 24-hour period (a good stand-in for salt intake) among more than 10,000 adults from 32 countries. The average was nearly 4,000 mg of sodium a day. Yet the range was huge, from 200 mg a day among the Yanomamo people of Brazil to 10,300 mg in northern Japan. Populations with higher salt consumption had higher average blood pressures and greater increases of blood pressures with age. Four groups of people—the four countries with salt intakes less than 1,300 mg per day—had low average blood pressures and little or no upward trend of blood pressure with age,
- The authors conducted a re-review and update on the Intersalt data. They found: 1) a stronger association than their prior study with higher sodium intakes and higher blood pressure, and 2) a stronger association with higher sodium intakes and higher blood pressure in middle age participants as compared with younger adults.
- TOHP: The two Trials of Hypertension Prevention (TOHP) were conducted from 1987-1995. They tested the impact of lifestyle changes on blood pressure, such as weight loss, stress management, nutritional supplements, and consuming less sodium. In each of the studies, small decreases in blood pressure were seen with sodium reduction over 18-36 months. Years after the trials had ended, the researchers surveyed the participants and found that:
- After an average of 10-15 years, the TOHP participants in the sodium-reduction groups were 25% less likely to have had a heart attack or stroke, to have needed a procedure to open or bypass a cholesterol-clogged coronary artery, or to have died of cardiovascular disease.
- The higher the ratio of potassium to sodium in a participant’s diet, the lower the chances were of developing cardiovascular trouble. This suggests that a strategy that includes both increasing potassium and lowering sodium may be the most effective way to fight high blood pressure.
- TOHP Follow-up Study : A continuation of the two previous TOHP trials in 2000 that looked specifically at CVD or deaths from CVD. When participants with sodium intakes less than 2,300 mg daily were compared with those who had intakes of 3,600-4,800 mg, there was a 32% lower risk of developing CVD. There was also a continuing decrease in CVD-related events (stroke, heart attack) with decreasing sodium intakes as low as 1,500 mg daily.
- DASH: The Dietary Approaches to Stop Hypertension (DASH) trials, begun in 1994, were major advances in blood pressure research, demonstrating the links between diet and blood pressure.
- In the first study, 459 participants were randomly assigned to either 1) a standard American diet high in red meat and sugars, and low in fiber, 2) a similar diet that was richer in fruits and vegetables, or 3) the ” DASH diet,” which emphasized fruits, vegetables and low-fat dairy foods, and limited red meat, saturated fats, and sweets. After eight weeks, the fruits and vegetables diet and DASH diet reduced systolic (the top number of a blood pressure reading) and diastolic (the bottom number of a blood pressure reading) blood pressure, with the DASH diet producing a stronger effect.
- The second study found that lowering sodium in either the DASH or standard American diet had an even stronger impact on reducing blood pressure. The DASH study contributed much of the scientific basis for the Dietary Guidelines for Americans 2010, which recommends reducing daily sodium to less than a teaspoon.
- A meta-analysis of clinical trials found that a moderate sodium reduction to about 4,000 mg a day for at least one month caused significant reductions in blood pressure in individuals with both normal and high blood pressure. Further analysis showed that blood pressure was reduced in both men and women and white and black races, suggesting a benefit for the total population.
Assessing people’s sodium intakes can be tricky, and the most accurate method known is to measure 24-urine samples over several days. This is the method Harvard researchers used when pooling data from 10,709 generally healthy adults from six prospective cohorts including the Nurses Health Studies I and II, the Health Professionals Follow-up Study, the Prevention of Renal and Vascular End-Stage Disease study, and the Trials of Hypertension Prevention Follow-up studies.
- They looked at both sodium and potassium intakes in relation to cardiovascular disease (CVD) risk (as noted by a heart attack, stroke, or procedure or surgery needed to repair heart damage), and measured two or more urine samples per participant.
- After controlling for CVD risk factors, they found that a higher sodium intake was associated with higher CVD risk.
For every 1,000 mg increase of urinary sodium per day, there was an 18% increased risk of CVD. But for every 1,000 mg increase of potassium, there was an 18% lower risk of CVD. They also found that a higher sodium-to-potassium ratio was associated with higher CVD risk, that is, eating a higher proportion of salty foods to potassium-rich foods such as fruits, vegetables, legumes, and low-fat dairy.
Chronic kidney disease Chronic kidney disease (CKD) shares risk factors with cardiovascular disease, with high blood pressure being a major risk factor for both. Salt sensitivity is reported to be more prevalent in patients with CKD due to a reduced ability to excrete sodium, which may lead to increased blood pressure.
Although there is evidence that links high sodium intake with high blood pressure, there is not adequate evidence that a low sodium restriction protects against or causes better outcomes of CKD than a moderate sodium restriction. One systematic review of patients diagnosed with CKD found that high sodium intakes of greater than 4,600 mg a day were associated with progression of CKD, but low sodium intakes less than 2,300 mg a day had no significant effect when compared with moderate sodium intakes of 2,300-4,600 mg a day.
Guidelines generally advise a moderate rather than low sodium restriction to prevent the development and progression of CKD. A daily sodium intake of less than 4,000 mg is recommended for overall management of CKD, and less than 3,000 mg daily for CKD with symptoms of fluid retention or proteinuria, a condition in which excess protein is excreted in the urine.
Osteoporosis The amount of calcium that your body loses via urination increases with the amount of salt you eat. If calcium is in short supply in the blood, it can leach out of bones. So a diet high in sodium could have an additional unwanted effect—the bone-thinning disease known as osteoporosis.
- A study in post-menopausal women showed that the loss of hip bone density over two years was related to the 24-hour urinary sodium excretion at the start of the study, and that the connection with bone loss was as strong as that for calcium intake.
- Other studies have shown that reducing salt intake causes a positive calcium balance, suggesting that reducing salt intake could slow the loss of calcium from bone that occurs with aging.
Cancer Research shows that a higher intake of salt, sodium, or salty foods is linked to an increase in stomach cancer. The World Cancer Research Fund and American Institute for Cancer Research concluded that salt, as well as salted and salty foods, are a “probable cause of stomach cancer.”
Does salt sweeten fruit?
The key is a sugar-ferrying protein in taste cells. It’s one of life’s little ironies: Sweet foods get sweeter when you add a little salt. Now, scientists may have provided connoisseurs of salted caramel and grapefruit with the reason this culinary trick is worth its salt.