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Rhizosphere microbial communities play an important role in maintaining the health and productivity of the plant host. The rhizobacteria Pseudomonas putida P2 of Ramonda serbica and Bacillus cereus P5 of R. nathaliae were selected for treatment of the Belija wheat cultivar because of their plant growth-promoting (PGP) properties. Compared to the non-treated drought-stressed plants, the plants treated with rhizobacteria showed increased activity of the two major antioxidant enzymes, superoxide dismutase, and ascorbate peroxidase. Plants treated with the B. cereus P5 strain exhibited higher proline content under drought stress, suggesting that proline accumulation depends on the relative water content (RWC) status of the plants studied. Inoculation of wheat seeds with the P. putida P2 strain improved water status by increasing RWC and alleviating oxidative stress by reducing H 2 O 2 and malondialdehyde concentrations in plants exposed to severe drought, possibly also helping plants to overcome drought through its 1-aminocyclopropane-1-carboxylic acid deaminase activity. Analysis of data from Next Generation sequencing (NGS) revealed that the dominant bacterial taxa in the rhizosphere of resurrection plants R. serbica and R. nathaliae were extremophilic, thermotolerant, Vicinamibacter silvestris, Chthoniobacter flavus, and Gaiella occulta. From the fungi detected Penicillium was the most abundant in both samples, while Fusarium and Mucor were present only in the rhizosphere of R. serbica and the entomopathogenic fungi Metarhizium, and Tolypocladiumu only in the rhizosphere of R. nathaliae. The fungal communities varied among plants, suggesting a stronger environmental influence than plant species. Our study demonstrates the importance of in vivo experiments to confirm the properties of PGP bacteria and indicates that the rhizosphere of resurrection plants is a valuable source of unique microorganisms that can be used to improve the drought stress tolerance of crops., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The purpose of this study is to analyse the effects of the Interactive Learning Materials Triangle (iLMT) on the learning and knowledge retention of 12-year-old students. The iLMT is a digital version of the standard school learning materials in Serbia, and is characterized by a high degree of interactivity and immediate feedback during the learning process. We conducted an experiment to explore whether iLMT influences student success in solving mathematical tasks that require different types of mathematical reasoning. Based on previous extensive research by Lithner, 4 types of tasks are discussed: high relatedness answer, high relatedness algorithm, local low relatedness, and global low relatedness. The study involved 633 students and 13 teachers of mathematics, equally distributed in control and test groups. The main findings indicate that student success on a knowledge test for high relatedness answer and local low relatedness tasks for the test group was significantly higher than for the control group. On the knowledge retention test, students in the test group outperformed students in the control group at high relatedness algorithm and local low relatedness tasks. Our results also suggest that, even when learning materials are carefully digitalized with the use of available technological advantages, student success in global low relatedness tasks may still be lacking., Supplementary Information: The online version contains supplementary material available at 10.1007/s10763-021-10151-8., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© Ministry of Science and Technology, Taiwan 2021.)

Chenopodium murale L. is an invasive weed species significantly interfering with wheat crop. However, the complete nature of its allelopathic influence on crops is not yet fully understood. In the present study, the focus is made on establishing the relation between plant morphophysiological changes and oxidative stress, induced by allelopathic extract. Phytotoxic medium of C. murale hairy root clone R5 reduced the germination rate (24% less than control value) of wheat cv. Nataša seeds, as well as seedling growth, diminishing shoot and root length significantly, decreased total chlorophyll content, and induced abnormal root gravitropism. The R5 treatment caused cellular structural abnormalities, reflecting on the root and leaf cell shape and organization. These abnormalities mostly included the increased number of mitochondria and reorganization of the vacuolar compartment, changes in nucleus shape, and chloroplast organization and distribution. The most significant structural changes were observed in cell wall in the form of amoeboid protrusions and folds leading to its irregular shape. These structural alterations were accompanied by an oxidative stress in tissues of treated wheat seedlings, reflected as increased level of H 2 O 2 and other ROS molecules, an increase of radical scavenging capacity and total phenolic content. Accordingly, the retardation of wheat seedling growth by C. murale allelochemicals may represent a consequence of complex activity involving both cell structure alteration and physiological processes.