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Background Salinity is one of the most challenging abiotic stresses restricting the growth of plants. In vitro screening will increase the efficiency and speed of salinity tolerant genotypes identifications. The response of four tomato cultivars under salinity was analyzed in vitro to evaluate the seedlings growth, biochemical, and gene expression responses as well as the effect of nano zinc and iron on callus induction and plant regeneration. Results The results showed that an increase in salinity stress in the medium decreased the germination percentage, fresh and dry weight of shoot, root length, chlorophyll a, b and carotenoids content, K and Ca content, and on the other hand, Na content was increased. MDA content (‘Nora’, ‘PS-10’, ‘Peto’ and ‘Roma’: 1.71, 1.78, 1.66 and 2.16 folds, respectively), electrolyte leakage (‘PS-10’: 33.33%; ‘Roma’: 56.33%), were increased with salinity of 100 mM compared to control. Proline content was increased in 50 mM NaCl (10.8 fold). The most activity of antioxidant enzymes including CAT, SOD, APX, GPX, and GR was observed in the ‘PS-10’ cultivar, and the lowest activity of these enzymes was observed in ‘Roma’ under salinity stress. The AsA and GSH were decreased and DHA and GSSG were increased with the increased intensity of salinity. The relative expression of SOD, APX, and GR genes varied in different cultivars at different salinity concentrations. The most percentage of callus induction was observed with applying iron oxide nanoparticles, and the most regeneration rate was recorded using zinc oxide nanoparticles. Conclusion The results showed that salt-tolerant cultivars such as ‘PS-10’ with better osmotic adjustment, are suitable candidates for the future production and breeding programs. The use of nutrient nanoparticles under salinity stress for different tomato cultivars increased their performance.

Biofertilizers, such as arbuscular mycorrhiza fungi (AMF) and seaweed extract (SWE), have been effective in environmental and agricultural ecosystems. In this study, the effects of AMF, SWE, and their co-application were assayed on the growth and antioxidant potential of lettuce plants. The experiment was conducted as a factorial based on a completely randomized design with two factors and four replications under greenhouse conditions. The first factor was AMF (Glomus mosseae) at two levels consisting of AMF application (20 g pot−1), and without using AMF; and the second factor was SWE foliar spraying (Ascophyllum nodosum) at 0.5, 1.5 and 3 g L−1 concentration. The results revealed that the highest root colonization (85%) belonged to AMF and SWE (3 g L−1) × AMF; the lowest colonization rate (65%) was observed for AMF × SWE (0.5 g L−1) treatment. The highest growth parameters (leaf number, shoot and root fresh weight, head diameter), biochemical traits (total soluble proteins, carbohydrates content) and TAA, total antioxidant activity by FRAP method and ascorbic acid, total phenolics, and flavonoids content were obtained with the co-applications. Therefore, the best results of the evaluated traits were achieved with AMF × SWE (3 g L−1). The TAA value was increased three-fold compared to the control. Total phenolics and flavonoids content were 2.24 and 6.59 times higher than the control, respectively. On the other hand, leaf dry weight was decreased with the further growth of the plants. Overall, the co-application of AMF with SWE can be recommended to producers as an alternative and environment-friendly strategy to improve the qualitative and quantitative traits of the lettuce crop.

In recent decades, the over-use of chemical fertilizers has imposed many environmental challenges worldwide. Nowadays, organic fertilizers such as vermicompost and livestock manure have gained a huge interest in sustainable agricultural systems. A 2-year field research was conducted as factorial based on a randomized complete block design to assay the fertilizer and humic acid (HA) efficiency on the growth responses and essential oil composition of Coriandrum sativum. The treatments were different fertilizer sources (livestock manure, vermicompost, and chemical fertilizers) and humic acid fertigation before and at the beginning of the flowering stage. The highest protein content was observed under vermicompost × HA application before flowering (0.118 μmol L−1 and 0.128 μmol L−1, respectively). Moreover, the co-application of organic fertilizers × HA at the beginning of flowering resulted in a significant increase in the photosynthetic pigments and N, P, K, Fe, Zn, and Mn content. According to the GC-FID and GC–MS analysis, linalool (55.91–63.19%), γ-terpinene (4.65–6.13%), α-pinene (2.64–5.74%), geranyl acetate (3.49–5.51%), 2-dodecanal (2.92–4.46%), menthol (1.33–3.90%), p-cymene (1.73–2.24%), and geraniol (1.25–2.15%) were the main essential oil constituents. The top linalool content was obtained by using chemical fertilizers and vermicompost × HA at the flowering onset stage. In general, the results revealed that chemical fertilizers could be replaced with vermicompost × HA and their co-application positively influenced the growth responses and the essential oil composition of coriander. Furthermore, the results obtained would be advisable to the extension section and the pioneer farmers to amend the large-scale production systems in favor of environmental health.