Table 1.
Characteristics of the microgreens cultivation process depending on the species.
| Common name | Scientific name | Determined TSW (g) | Sowing rate per tray (g) | Number of seeds per cm2 | Number of days in darkness | Number of days in the light | Entire cultivation period in days |
|---|---|---|---|---|---|---|---|
| Cress | L. sativum L. | 2.4 | 3 | 7.6 | 2 | 5 | 7 |
| Mustard | S. alba L. | 5.8 | 7 | 7.3 | 3 | 3 | 6 |
| Broccoli | B. oleracea L. var. italica | 3.1 | 7 | 13.7 | 3 | 7 | 10 |
| Basil | O. basilicum L. | 1.5 | 3 | 12.1 | 3 | 3 | 6 |
| Sunflower | H. annuus L. | 60.9 | 18 | 1.8 | 4 | 5 | 9 |
| Cucumber | C. sativus L. | 22.8 | 6 | 1.6 | 3 | 8 | 11 |
Table 2.
Parameters of the MgSO4 solution.
| Treatment | Mg concentration (mg · L−1) | pH value | EC (μs · cm−1) |
|---|---|---|---|
| Mg1 | 10 | 8.04 | 700 |
| Mg2 | 20 | 7.83 | 1210 |
| Mg3 | 30 | 7.66 | 1670 |
| Mg4 | 40 | 7.47 | 1990 |
| Mg5 | 50 | 7.20 | 2500 |
Table 3.
Total amount of magnesium applied per tray (mg) calculated based on the cultivation duration, irrigation requirements of each species and MgSO4 treatment.
| Cultivated species | Cultivation days | Treatment | ||||
|---|---|---|---|---|---|---|
| Mg1 | Mg2 | Mg3 | Mg4 | Mg5 | ||
| Cress | 7 | 1.01 | 2.03 | 3.04 | 4.05 | 5.07 |
| Mustard | 6 | 0.74 | 1.48 | 2.22 | 2.95 | 3.69 |
| Broccoli | 10 | 1.20 | 2.40 | 3.61 | 4.80 | 6.01 |
| Basil | 6 | 0.50 | 1.00 | 1.50 | 2.00 | 2.50 |
| Sunflower | 9 | 1.11 | 2.23 | 3.35 | 4.45 | 5.57 |
| Cucumber | 11 | 1.97 | 3.93 | 5.90 | 7.86 | 9.82 |
Figure 1.
Water-soluble magnesium content in the studied species. Bars marked with different letters indicate statistically significant differences between treatments (p < 0.05): (A) cress; (B) mustard; (C) broccoli; (D) basil; (E) sunflower; (F) cucumber.
Table 4.
Percentage increase in magnesium content depending on the concentration of the biofortification solution and tested microgreen species.
| Treatment | Cress (%) | Mustard (%) | Broccoli (%) | Basil (%) | Sunflower (%) | Cucumber (%) |
|---|---|---|---|---|---|---|
| C | 0 | 0 | 0 | 0 | 0 | 0 |
| Mg1 | 74.23 | 5.40 | 26.75 | 42.61 | 43.62 | 30.42 |
| Mg2 | 69.01 | 15.57 | 49.29 | 104.21 | 44.34 | 81.37 |
| Mg3 | 108.36 | 33.56 | 61.83 | 161.28 | 50.97 | 118.62 |
| Mg4 | 145.82 | 61.49 | 81.14 | 151.85 | 35.97 | 125.85 |
| Mg5 | 171.96 | 66.78 | 136.93 | 262.18 | 80.92 | 185.59 |
Table 5.
Water-soluble calcium content in the studied species (mg · kg−1 FW).
| Treatment | Cress | Mustard | Broccoli | Basil | Sunflower | Cucumber |
|---|---|---|---|---|---|---|
| C | 195.3 ± 0.6 ab | 166.8 ± 5.8 c | 122.8 ± 4.5 b | 149.1 ± 17.2 a | 118.2 ± 2.7 a | 210.5 ± 14.4 ab |
| Mg1 | 218.3 ± 22.5 ab | 161.7 ± 5.2 c | 132.6 ± 5.1 b | 148.2 ± 9.6 a | 135.9 ± 16.7 a | 182.0 ± 6.6 b |
| Mg2 | 177.3 ± 7.5 b | 160.4 ± 5.7 c | 132.4 ± 8.9 b | 158.2 ± 10.8 a | 116.3 ± 10.5 a | 225.9 ± 3.2 ab |
| Mg3 | 233.0 ± 21.8 ab | 204.2 ± 4.1 b | 130.8 ± 4.0 b | 166.3 ± 21.6 a | 125.0 ± 2.7 a | 241.6 ± 12.8 a |
| Mg4 | 282.9 ± 18.3 a | 218.1 ± 11.1 ab | 144.8 ± 5.5 ab | 129.4 ± 8.7 a | 105.1 ± 4.7 a | 232.9 ± 20.1 ab |
| Mg5 | 286.6 ± 19.9 a | 237.6 ± 4.5 a | 165.7 ± 4.2 a | 166.7 ± 16.3 a | 122.0 ± 7.4 a | 252.8 ± 10.4 a |
Figure 2.
Results of analysis of linear correlation between Ca and Mg content in microgreens of tested species: (A) cress; (B) mustard; (C) broccoli; (D) basil; (E) sunflower; (F) cucumber. Dashed lines represent the 95% confidence intervals of the regression lines.
Table 6.
Dry matter content in the studied species (% FW).
| Treatment | Cress | Mustard | Broccoli | Basil | Sunflower | Cucumber |
|---|---|---|---|---|---|---|
| C | 7.8 ± 0.2 a | 8.7 ± 0.4 b | 8.8 ± 0.3 a | 11.1 ± 1.2 a | 9.8 ± 0.3 a | 9.9 ± 0.5 a |
| Mg1 | 8.4 ± 0.7 a | 8.7 ± 0.4 b | 9.3 ± 0.3 a | 11.0 ± 0.7 a | 10.4 ± 1.2 a | 8.2 ± 0.1 a |
| Mg2 | 6.9 ± 0.2 a | 8.9 ± 0.2 b | 9.0 ± 0.4 a | 12.3 ± 0.6 a | 9.2 ± 0.8 a | 9.2 ± 0.1 a |
| Mg3 | 7.3 ± 0.5 a | 9.8 ± 0.1 ab | 9.1 ± 0.5 a | 12.7 ± 1.6 a | 9.9 ± 0.4 a | 9.0 ± 0.4 a |
| Mg4 | 8.2 ± 0.5 a | 10.8 ± 0.6 a | 9.6 ± 0.5 a | 10.7 ± 0.7 a | 8.0 ± 0.3 b | 8.9 ± 0.6 a |
| Mg5 | 8.8 ± 0.7 a | 10.5 ± 0.1 a | 9.8 ± 0.2 a | 13.7 ± 1.3 a | 10.4 ± 0.6 a | 9.7 ± 0.4 a |
Figure 3.
Total fresh yield (g · m−2) of microgreens at different magnesium concentrations: (A) cress; (B) mustard; (C) broccoli; (D) basil; (E) sunflower; (F) cucumber. Bars marked with different letters indicate statistically significant differences between treatments at p < 0.05.
Table 7.
Comparison of microgreen yields of the tested species.
| Species | Total yield | Yield of edible parts | ||
|---|---|---|---|---|
| g · g−1 seed* | Yield (g · m−2) | g · g−1 seed | Yield (g · m−2) | |
| Cress | 9.9 ± 0.3 b | 1805 ± 53 e | 9.9 ± 0.3 b** | 1805 ± 53 e** |
| Mustard | 6.0 ± 0.1 d | 2547 ± 49 d | 6.0 ± 0.1 d** | 2547 ± 49 d** |
| Broccoli | 7.7 ± 0.1 c | 3259 ± 46 c | 4.5 ± 0.1 b | 1925 ± 22 b |
| Basil | 7.3 ± 0.2 c | 1318 ± 27 f | 7.3 ± 0.2 c** | 1318 ± 27 f** |
| Sunflower | 4.5 ± 0.1 e | 4861 ± 77 a | 2.1 ± 0.1 c | 2302 ± 78 a |
| Cucumber | 11.3 ± 0.2 a | 4114 ± 73 b | 5.7 ± 0.1 a | 2070 ± 50 b |
Figure 4.
Dependence of the content of analysed components in broccoli microgreens on the applied concentration of magnesium sulphate solution. Bars marked with different letters indicate statistically significant differences between treatments (p < 0.05): (A) vitamin C, (B) total phenols, (C) antioxidant activity, (D) flavonoids, (E) dry matter.
Table 8.
Comparison of analytical parameters within species regardless of treatment.
| Species | Vitamin C (mg · kg−1 FW) | Antioxidant activity (DPPH) (mg · kg−1 FW) | Flavonoids (mg · kg−1 FW) | Total phenols (mg · kg−1 FW) | Dry matter (% FW) |
|---|---|---|---|---|---|
| Cress | 167.7 ± 7.4 c | 886.9 ± 24.6 b | 305.2 ± 7.1 c | 1909.7 ± 68.5 b | 7.9 ± 0.2 c |
| Mustard | 312.2 ± 7.8 b | 906.8 ± 23.2 ab | 341.0 ± 9.9 c | 3445.5 ± 102.1 a | 9.6 ± 0.2 b |
| Broccoli* | 748.4 ± 6.5 a | 997.9 ± 8.2 a | 353.9 ± 5.4 c | 1707.9 ± 12.6 b | 9.2 ± 0.2 b |
| Basil | 43.3 ± 1.8 e | 563.4 ± 23.1 c | 528.9 ± 30.0 a | 1017.7 ± 40.9 c | 11.9 ± 0.5 a |
| Sunflower | 51.8 ± 2.1 e | 410.2 ± 35.6 d | 423.9 ± 22.4 b | 1004.4 ± 56.3 c | 9.6 ± 0.3 b |
| Cucumber | 74.7 ± 2.5 d | 150.4 ± 6.1 e | 145.7 ± 4.3 d | 661.8 ± 14.8 d | 9.1 ± 0.2 b |
Figure 5.
Relationship between magnesium content and selected parameters for broccoli microgreens: (A) relationship between magnesium content and flavonoid content; (B) relationship between magnesium content and vitamin C content. Values represent individual data points with the fitted regression line and 95% confidence intervals.
Table S1.
Magnesium content in the studied species (mg·kg−1 FW) as dependent on the applied MgSO4 treatments
| Treatment | Cress | Mustard | Broccoli | Basil | Sunflower | Cucumber |
|---|---|---|---|---|---|---|
| C | 216.8 ± 22.4 c | 369.8 ± 14.6 d | 319.1 ± 6.9 e | 150.7 ± 17.5 c | 203.7 ± 5.5 b | 376.8 ± 19.8 d |
| Mg1 | 377.8 ± 51.2 bc | 389.8 ± 21.7 d | 404.4 ± 10.6 de | 214.9 ± 19.6 bc | 292.5 ± 36.1 ab | 491.4 ± 6.9 cd |
| Mg2 | 366.5 ± 7.0 bc | 427.4 ± 15.6 cd | 476.5 ± 24.5 cd | 307.8 ± 16.8 bc | 294.0 ± 25.9 ab | 683.4 ± 18.5 bc |
| Mg3 | 451.8 ± 38.9 ab | 493.9 ± 15.1 bc | 516.5 ± 25.9 bc | 393.8 ± 65.8 ab | 307.5 ± 7.3 a | 823.7 ± 55.8 b |
| Mg4 | 533.1 ± 39.3 ab | 556.3 ± 32.2 ab | 581.0 ± 19.5 b | 379.6 ± 17.3 ab | 276.9 ± 10.8 ab | 850.9 ± 122.9 ab |
| Mg5 | 589.7 ± 66.2 a | 616.8 ± 13.4 a | 756.05 ± 14.4 a | 545.8 ± 57.0 a | 368.5 ± 18.1 a | 1076.1 ± 30.1 a |
Table S2.
Selected bioactive parameters of microgreen species under different Mg treatments
| Treatment | Vitamin C (mg · kg−1 FW) | Antioxidant activity (DPPH) (mg · kg−1 FW) | Flavonoids (mg · kg−1 FW) | Total phenols (mg · kg−1 FW) |
|---|---|---|---|---|
| Cress | ||||
| C | 197.3 ± 33.8 a | 845.3 ± 62.9 a | 289.9 ± 2.1 a | 1624.0 ± 57.2 a |
| Mg1 | 193.6 ± 19.3 a | 886.2 ± 81.7 a | 313.2 ± 21.6 a | 1829.3 ± 260.8 a |
| Mg2 | 160.0 ± 6.1 a | 856.8 ± 47.2 a | 278.9 ± 8.7 a | 1885.1 ± 82.4 a |
| Mg3 | 169.4 ± 13.4 a | 843.8 ± 38.2 a | 303.6 ± 8.8 a | 1893.4 ± 97.0 a |
| Mg4 | 159.7 ± 16.1 a | 952.9 ± 83.9 a | 329.6 ± 25.1 a | 2128.2 ± 230.6 a |
| Mg5 | 136.0 ± 5.8 a | 922.5 ± 62.2 a | 310.7 ± 16.1 a | 2003.0 ± 123.7 a |
| Mustard | ||||
| C | 297.4 ± 5.0 a | 889.5 ± 77.3 a | 394.3 ± 14.0 a | 3431.8 ± 224.7 a |
| Mg1 | 285.8 ± 16.7 a | 885.8 ± 84.3 a | 355.9 ± 28.9 a | 3919.3 ± 148.4 a |
| Mg2 | 304.6 ± 23.5 a | 827.4 ± 45.9 a | 309.6 ± 6.6 a | 2974.2 ± 362.4 a |
| Mg3 | 321.6 ± 5.9 a | 936.7 ± 71.4 a | 308.3 ± 19.3 a | 3275.4 ± 167.7 a |
| Mg4 | 309.7 ± 9.9 a | 962.5 ± 28.9 a | 318.1 ± 8.2 a | 3499.8 ± 100.7 a |
| Mg5 | 345.1 ± 31.3 a | 938.6 ± 18.2 a | 356.8 ± 24.3 a | 3730.3 ± 47.1 a |
| Broccoli | ||||
| C | 751.3 ± 31.9 b | 1008.5 ± 19.5 b | 360.4 ± 23.2 b | 1699.9 ± 2.5 b |
| Mg1 | 747.3 ± 10.8 b | 991.8 ± 21.9 b | 345.5 ± 3.9 b | 1673.9 ± 7.0 b |
| Mg2 | 741.3 ± 13.8 b | 1010.5 ± 21.5 b | 352.9 ± 3.6 b | 1694.0 ± 42.2 b |
| Mg3 | 744.8 ± 3.8 b | 993.2 ± 22.1 b | 361.8 ± 6.9 b | 1752.4 ± 24.6 b |
| Mg4 | 757.5 ± 6.4 b | 985.7 ± 17.1 b | 349.3 ± 17.0 b | 1717.2 ± 26.7 b |
| Mg5 | 882.5 ± 13.3 a | 1123.3 ± 23.5 a | 478.5 ± 13.5 a | 1884.0 ± 16.5 a |
| Basil | ||||
| C | 44.8 ± 2.7 a | 551.2 ± 86.4 a | 474.8 ± 107.9 ab | 1041.9 ± 120.0 a |
| Mg1 | 43.1 ± 5.8 a | 618.4 ± 26.7 a | 575.1 ± 50.3 ab | 1114.6 ± 30.7 a |
| Mg2 | 37.2 ± 5.2 a | 478.0 ± 5.7 a | 457.7 ± 15.3 ab | 1016.5 ± 121.4 a |
| Mg3 | 39.1 ± 1.3 a | 669.7 ± 12.2 a | 662.4 ± 10.7 a | 1135.6 ± 7.3 a |
| Mg4 | 44.4 ± 3.2 a | 524.2 ± 38.4 a | 535.1 ± 21.8 ab | 942.2 ± 114.4 a |
| Mg5 | 51.3 ± 4.2 a | 478.0 ± 53.5 a | 378.3 ± 31.1 b | 785.9 ± 45.6 a |
| Sunflower | ||||
| C | 56.3 ± 5.8 a | 430.3 ± 9.7 ab | 481.5 ± 24.1 a | 1251.10 ± 129.2 a |
| Mg1 | 47.2 ± 5.7 a | 375.5 ± 819.5 ab | 415.4 ± 50.5 a | 872.8 ± 70.0 a |
| Mg2 | 41.6 ± 2.3 a | 328.8 ± 54.0 b | 402.6 ± 45.3 a | 849.3 ± 77.9 a |
| Mg3 | 50.5 ± 2.1 a | 349.1 ± 26.5 ab | 382.4 ± 46.9 a | 906.0 ± 61.3 a |
| Mg4 | 51.6 ± 4.5 a | 471.1 ± 132.0 ab | 390.6 ± 74.1 a | 1092.3 ± 191.0 a |
| Mg5 | 61.9 ± 6.4 a | 564.5 ± 146.5 a | 478.9 ± 84.3 a | 1054.7 ± 180.7 a |
| Cucumber | ||||
| C | 78.8 ± 5.4 a | 161.1 ± 14.6 ab | 135.7 ± 8.8 a | 703.5 ± 56.1 ab |
| Mg1 | 66.1 ± 1.6 a | 154.5 ± 7.7 ab | 144.3 ± 11.5 a | 650.5 ± 14.6 ab |
| Mg2 | 73.5 ± 6.6 a | 180.9 ± 8.4 a | 145.4 ± 6.7 a | 694.5 ± 26.9 ab |
| Mg3 | 70.5 ± 5.4 a | 127.1 ± 9.9 b | 137.5 ± 11.7 a | 657.0 ± 34.3 ab |
| Mg4 | 81.2 ± 7.1 a | 144.9 ± 4.9 ab | 152.2 ± 12.3 a | 612.9 ± 28.3 bc |
| Mg5 | 83.7 ± 10.7 a | 123.2 ± 0.9 b | 169.3 ± 9.9 a | 620.6 ± 17.1 bc |
Table S3.
Yield of tested microgreen species as dependent on the applied MgSO4 treatments (g · m−2)
| Treatment | Cress | Mustard | Broccoli | Basil | Sunflower | Cucumber |
|---|---|---|---|---|---|---|
| C | 1932 ± 5 a | 2400 ± 202 a | 3183 ± 86 a | 1265 ± 54 a | 5041 ± 84 a | 3975 ± 259 a |
| Mg1 | 1949 ± 111 a | 2561 ± 131 a | 3275 ± 85 a | 1395 ± 46 a | 5021 ± 168 a | 4285 ± 213 a |
| Mg2 | 1775 ± 104 a | 2624 ± 89 a | 3446 ± 141 a | 1324 ± 112 a | 5224 ± 203 a | 4017 ± 254 a |
| Mg3 | 1691 ± 82 a | 2535 ± 46 a | 3399 ± 99 a | 1369 ± 43 a | 4674 ± 113 a | 4241 ± 104 a |
| Mg4 | 1714 ± 254 a | 2581 ± 148 a | 3180 ± 123 a | 1317 ± 58 a | 4657 ± 141 a | 3987 ± 45 a |
| Mg5 | 1858 ± 57 a | 2515 ± 140 a | 3069 ± 70 a | 1237 ± 58 a | 4610 ± 82 a | 4078 ± 69 a |