Spain is positioned as the top producer of strawberries in the European Union, with a production of 325,880 metric tonnes in 2022, which represents approximately 29% of all strawberries produced in Europe (FAOSTAT, 2022).
Strawberry crops are considerably sensitive to salinity, with yield loss thresholds starting from an electrical conductivity of the soil saturation extract (ECe) of 0.9 mS/cm (FAO). Currently, more than 800 million hectares of soil are saline worldwide, and it is estimated that 20% of arable land is affected by this phenomenon.
*Max. ECe maximum electrical conductivity in saturated soil extract that can support the crop. From this number onwards, growth stops and 100% of crop losses occur. mS/cm
Furthermore, osmotic stress related to high salinity and water stress are more frequent causes of calcium deficiency in fruit than that produced by high humidity, which leads to calcium deficiency in leaves and flowers. (Guichard et al., 2001). Calcium is a relatively non-mobile element that is transported by the plant mainly through the xylem. Due to excess salt in the soil, we reduce the translocation of this element to organs that are growing, such as meristems, new leaves, flowers and fruits.
The use of microorganisms can help mitigate the negative effects of salinity on crops and improve their productivity, since it reduces the presence of ethylene under stress conditions. Another measure that helps reduce salt in the soil is the use of calcium-based formulations. Calcium displaces the Na cation from the exchange complex, leaving it as a free ion in the medium, where it can be washed by the irrigation water.
The use of PGPR in combination with calcium-rich formulations makes it possible to implement a comprehensive 360º strategy, addressing the solution at both the plant and soil levels.
Impact of salinity on strawberry crops
In trials carried out under controlled conditions, in which salinity conditions were induced in the “Candela” strawberry variety crop, the onset of calcium deficiencies was observed in both leaves and flowers. This deficiency can be attributed to the presence of sodium chloride in the soil, which reduces the movement of nutrients and limits their absorption by the plant.
The trial evaluated the number of plants exhibiting symptoms of calcium deficiency in both the leaves and flowers. As shown in the figure, as the days with plants subjected to saline stress increased, there was an increase in plants showing symptoms in both the leaves and flowers. It should be noted that calcium was already being applied to the crop from the beginning in the nutrient solution used, but even with this, the deficiency was not avoided.
At the end of the trial, the control plants subjected to saline stress showed a 43.75% incidence of symptoms in the leaves and flowers. It was determined that in plants with saline stress to which BACNIFOS® + DESTROY SALT® (7% CaO) was applied, the onset of symptoms of calcium deficiency decreased by 71.4% in leaves and by 42.9% in flowers, with statistical differences at 13DAC in the flower symptoms.
**Tukey p<0.001 *percentage reduction in deficiency compared to the control with salinity ES: plants subjected to saline stress 21 days 50mM NaCl
**Tukey p<0.001 *percentage reduction in deficiency compared to the control with salinity ES: plants subjected to saline stress 21 days 50mM NaCl
ES: plants subjected to saline stress 21 days 50mM NaCl
ES: plants subjected to saline stress 21 days 50mM NaCl
ES: plants subjected to saline stress 21 days 50mM NaCl
The combination of BACNIFOS®, a product based on PGPR bacteria that are highly effective in forming ACC deaminase (stress mitigators), and DESTROY SALT®, a calcium-based desalinator complexed with organic acids and lignosulfonates, reduces the damage caused by excess salt in the soil and the side effects that this entails, such as the onset of calcium deficiencies in plants.
REFERENCES
- Gao, Y., Zou, H., Wang, B., & Yuan, F. (2022). Progress and applications of plant growth-promoting
bacteria in salt tolerance of crops. International Journal of Molecular Sciences, 23(13), 7036. - Gulen, H., & Eris, A. (2003). Some physiological changes in strawberry (Fragaria× ananassa ‘Camarosa’) plants under heat stress. The Journal of Horticultural Science and Biotechnology, 78(6), 894-898.
- FAOSTAT 2022 . https://www.fao.org/faostat/es/#data/QCL
- Guichard, S., Bertin, N., Leonardi, C., & Gary, C. (2001). Tomato fruit quality in relation to water and carbon fl uxes. Agronomie, 21(4), 385-392.
- García-López, J. V., Redondo-Gómez, S., Flores-Duarte, N. J., Rodríguez-Llorente, I. D., Pajuelo, E., & Mateos-Naranjo, E. (2024). PGPR-based biofertilizer modulates strawberry photosynthetic apparatus tolerance responses by severe drought, soil salinization and short extreme heat event. Plant Stress, 12, 100448.
- Redondo-Gómez, S., García-López, J. V., Mesa-Marín, J., Pajuelo, E., Rodriguez-Llorente, I. D., & Mateos-Naranjo, E. (2022). Synergistic effect of plant-growth-promoting rhizobacteria improves strawberry growth and fl owering with soil salinization and increased atmospheric CO2 levels and temperature conditions. Agronomy, 12(9), 2082.
- Kesici, M., Gulen, H., Ergin, S., Turhan, E., Ahmet, I. P. E. K., & Koksal, N. (2013). Heat-stress tolerance of some strawberry (Fragaria× ananassa) cultivars. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 41(1), 244-249.
- Karlidag, H., Yildirim, E., Turan, M., Pehluvan, M., & Donmez, F. (2013). Plant growth-promoting rhizobacteria mitigate deleterious effects of salt stress on strawberry plants (Fragaria× ananassa). HortScience, 48(5), 563-567.
- Arıkan, Ş., İpek, M., Eşitken, A., Pırlak, L., Dönmez, M. F., & Turan, M. (2020). Plant growth promoting rhizobacteria mitigate deleterious combined effects of salinity and lime in soil in strawberry plants. Journal of Plant Nutrition, 43(13), 2028-2039.
- Yaghubi, K., Ghaderi, N., Vafaee, Y., & Javadi, T. (2016). Potassium silicate alleviates deleterious effects of salinity on two strawberry cultivars grown under soilless pot culture. Scientia Horticulturae, 213, 87-95.
- Malekzadeh Shamsabad, M. R., Roosta, H. R., & Esmaeilizadeh, M. (2021). Responses of seven strawberry cultivars to alkalinity stress under soilless culture system. Journal of Plant Nutrition, 44(2), 166-180.
To find out more about what biotechnology is, its types and applications, the AgroTech and BioTech projects that we carry out at Fertiberia, and the biotechnological products that we develop, visit our specific section with related information.
