Author(s)

Mahmoud Samir El-Sharkawy¹, Talaat Rizk El-Beshsbeshy¹, Esawy Kasem Mahmoud¹, Nasser Ibrahim Abdelkader¹, Rania Mohamed Al-Shal¹, Ali M. Missaoui²

¹Soil Science and Water Department, Faculty of Agriculture, Tanta University, Tanta, Egypt.
²Department of Crop and Soil Sciences and Institute of Plant Breeding Genetics and Genomics, University of Georgia, Athens, GA, USA.

A greenhouse study was conducted to explore the effect of various rates of potassium sulfate (K₂SO₄) nanoparticles on alfalfa (Medicago sativa L.) growth and physiological response under salt stress. One salt-tolerant genotype (Mesa-Sirsa) and one salt-sensitive genotype (Bulldog 505) were selected based on germination under salt and were planted in pots containing 2 kg of sand. The two genotypes were subjected to 0 and 6 dS·m^-1 salt levels using CaCl₂·2H₂O: NaCl (2:1) mixed with Hoagland solution. Three K₂SO₄ nanoparticle treatments consisting of, 1/4, 1/8, and 1/10 of the potassium (K) level in full strength Hoagland solution (235 mg·L^-1) were applied. Adding K₂SO₄ nanoparticles at the 1/8 level resulted in the highest shoot dry weight, relative yield, root length and root dry weight in both genotypes. The different rates of K₂SO₄ nanoparticles affected significantly Na/K ratio and the concentrations of Calcium (Ca), Phosphorus (P), Copper (Cu), Manganese (Mn), and Zinc (Zn) in plant tissue. The application of K₂SO₄ nanoparticles at the 1/8 rate enhanced the plant’s physiological response to salt stress by reducing electrolyte leakage, increasing catalase and proline content, and increasing antioxidant enzymes, activity. These results suggest that the application of K nanoparticles may have better efficiency than conventional K fertilizers in providing adequate plant nutrition and overcoming the negative effects of salt stress in alfalfa.

Alfalfa, Nanoparticles, Salt Stress, Potassium

El-Sharkawy, M. , El-Beshsbeshy, T. , Mahmoud, E. , Abdelkader, N. , Al-Shal, R. and Missaoui, A. (2017) Response of Alfalfa under Salt Stress to the Application of Potassium Sulfate Nanoparticles. American Journal of Plant Sciences, 8, 1751-1773. doi: 10.4236/ajps.2017.88120.