محمد باقر حسن پور اقدم

Aloe vera L. is a perennial drought-tolerant plant commonly used in the pharmaceutical, food, and cosmetic industries. To evaluate the effects of foliar application of KNO3, nano-Zn, and Fe (0 and 2 mgL-1) on Aloe vera plants under NaCl salinity stress (0, 50, 100 mM), a factorial experiment based on a completely randomized design was conducted. The results revealed that foliar appli-cations influenced root dry weight. Chlorophyll b content was affected by the salinity × foliar application. Total soluble solids content, chlorophyll a, phenolics and flavonoids of leaves, gel content, catalase and superoxide dismutase activity, malondialdehyde, proline, and mineral nu-trients content were responded to the treatments as well. The highest gel content (0.37 g per leaf) and plant dry weight (13.1 g per pot) were recorded at NaCl0 × KNO3+nano-Fe. The top K/Na ra-tio (35.2), K (69 g Kg-1), P (6.6 g Kg-1), Ca (31 g Kg-1), and Mg (2.5 g Kg-1) content were recorded at NaCl0 × KNO3 treatment. The most Fe content (383 g Kg-1) was observed at NaCl0 × nano-Fe, and the maximum Zn content (37.6 mg Kg-1) was recorded at NaCl0 × nano Zn. 100 mM NaCl in-creased malondialdehyde and Na content. The highest catalase activity belonged to NaCl50 × KNO3 + nano-Zn treatment. Salinity stress had adverse effects on the growth and physiological responses of Aloe vera, however, the foliar application of KNO3, nano-Zn, and Fe mitigated the damaging effects of salinity. The result from more detailed studies would be advisable to pio-neer farmers and the agricultural sector.