Atici, Ökkeş; Aydın, İhsan; Karakus, Sinem; Tiryaki, Deniz

Salinity stress is a major environmental factor that poses a significant constraint to plant growth, threatening agricultural productivity and sustainability. This study investigated the potential of halotolerant bacteria, isolated from the rhizosphere of wild halotolerant plants in Turkey’s Salt Lake basin, to enhance salt stress tolerance in maize (Zea mays L.). The rhizospheres of 17 different wild halotolerant plants were selected for bacterial isolation, resulting in the identification of 22 halotolerant bacteria using 16S rRNA sequence analysis. Among these, 19 isolates were found to possess positive activity for 1-aminocyclopropane-1-carboxylate (ACC) deaminase and nitrogen fixation. When the maize seeds inoculated with these 19 isolates were grown under normal conditions, four isolates‒TG-4 (Halomonas arcis), TG-8 (Marinococcus tarigensis), TG-12 (Halobacillus dabanensis), and TG-20 (Halomonas eurihalina)–significantly stimulated seedling growth and development. To evaluate the effect of these four isolates on salt tolerance, inoculated seeds were grown under various salt conditions (0.0, 75, 150, and 250 mM NaCl). The responses of plants to salt stress were analyzed by evaluating growth parameters, membrane damage, photosynthetic pigment and proline content, reactive oxygen species and lipid peroxidation levels, and antioxidant enzyme activities. According to the parameters, the results indicated that TG-4, TG-8, and TG-12, in particular, have the potential to function as plant growth-promoting rhizobacteria and effectively enhance salt stress tolerance in the maize seedlings. Overall, this research highlights the potential of halotolerant bacteria to improve salt stress tolerance in maize plants through multifaceted mechanisms, offering valuable insights for sustainable agriculture in saline environments.

Osma, Etem; Varol, Tuğçe; Elveren, Müjgan

In this study, 25 plant species growing in different habitats in Erzincan province were studied with gypsum (Ebenus macrophylla, Gypsophila lepidioides, Linum flavum, Onobrychis nitida, Paracaryum stenolophum, Psephellus recepii, Tanacetum heterotomum, Verbascum alyssifolium), limestone (Alkanna megacarpa, Alyssum sibiricum, Anthemis sp., Astragalus sp., Chrysophthalmum montanum, Ebenus laguroides, Genista aucheri, Pelargonium endlicherianum, Stachys sparsipilosa), or serpentine (Artedia squamata, Consolida olopetala, Convolvulus pseudoscammania, Erysimum pulchellum, Fumana aciphylla, Gladiolus halophilus, Hypericum thymbrifolium, Salvia indica). Within the scope of the study, element concentrations were determined in plants with different flower colors (yellow, purple–blue–pink, white) and in the soils where they grow. Our goal was to assess whether there were differences in mineral element concentrations within plants from these different areas and whether those differences (if they existed) led to changes in plant morphology, specifically flower coloration. The flowers, leaves and root parts of the collected plants and the soils of the habitats where they grow were pre-treated in the laboratory. Mineral element concentrations in the prepared samples were determined by ICP-MS. Plant and soil data obtained were statistically evaluated, and the differences between the habitats were determined. It was observed that there were differences in terms of mineral elements in the generative and vegetative parts of the plant and these differences impacted flower color; these coloration differences in plants from other areas might be used to indicate the presence of potentially important minerals.