The Persian walnut (Juglans regia L.) is one of the most lucrative and widely distributed nut crops. It is appreciated as a forestry and ornamental tree in addition to its benefits as a fruit crop. Although Central Asian countries, especially Uzbekistan, are among the origins of the Persian walnut; they are not considered as top industrial producers of walnuts. Uzbekistan possesses a wide range of walnut genetic resources and as a result of conducted research, several promising, fruitful, early-harvesting varieties and forms have been selected. The aim of this study is to optimize microclonal in vitro propagation of selected Uzbekistan local varieties and forms by evaluating concentrations of different plant growth regulators and genotype on multiplication and rooting stages. As mother plants, 2 forms and one variety were selected: the Ideal variety, 'Form PDM23' and 'Form 202YaKT'. ?n the proliferation stage, the growth rate of walnut microshoots on basal medium Driver and Kuniyuki Walnut Medium (DKW) with different concentrations of 6-benzylaminopurine (BAP) and Indole-3-butyric acid (IBA) (0.01 mg/L) was studied. The rooting stage was assessed in half strength macronutrient DKW medium containing different IBA concentrations (0.0, 2.0, 4.0 and 6.0 mg/L). The Ideal variety and 'Form PDM23' performed best in DKW medium supplied with 1.5 mg/L BAP and 0.01 mg/L IBA, whereas 'Form 202YaKT' performed best in DKW medium supplemented with 1.0 mg/L BAP and 0.01 mg/ L IBA for the proliferation stage. For all genotypes, 6.0 mg/L IBA provided the best rooting results.

Plant oxylipins are a diverse group of oxygenated fatty acid derivatives that function as important signaling molecules in plant responses to abiotic stress. Although jasmonates, particularly jasmonic acid (JA) and its derivatives, have been extensively studied, increasing evidence demonstrates that other oxylipin classes, including 12-oxophytodienoic acid (OPDA), green leaf volatiles (GLVs), reactive electrophilic oxylipins (RES), and peroxygenase (PXG)-derived oxylipins, also contribute to stress adaptation. This review summarizes current understanding of the molecular mechanisms underlying oxylipin signal perception, transduction, and regulation, with particular emphasis on interactions with other plant hormone pathways, reactive oxygen species (ROS), Calcium (Ca²⁺), and mitogen-activated protein kinase (MAPK) signaling. We further examine transcriptional, post-transcriptional, and post-translational mechanisms that regulate oxylipin responses and discuss their integration across individual and combined abiotic stresses. Particular attention is given to experimentally established mechanisms while distinguishing emerging or unresolved signaling processes. Understanding these interconnected signaling mechanisms will be important for developing strategies to improve crop resilience under global climate change.

In this study, the biological activity of two-year-old Aronia melanocarpa (Michx.) Elliot plants in vitro micro propagated was evaluated. The phytochemical composition of ethanol extracts obtained from the leaves and fruits of the plant and their antibacterial activity against pathogenic bacteria were studied. In phytochemical screening experiments, secondary metabolites in the extracts were determined using qualitative tests: tannins, flavonoids, phenolic compounds, saponins and terpenoids. For antibacterial analysis, 30, 50, 70 and 90 % ethanol solutions of fruit and leaf extracts were prepared and according to the results obtained, 50 % ethanol extract was selected as the optimal concentration for antibacterial activity. Antibacterial activity was evaluated using the disc-well method and the pathogenic bacteria Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis were selected. The effect of the extracts on bacterial growth at different concentrations was determined by the diameter (mm) of the inhibition zones formed around the bacterial colonies. The experimental results showed that the antibacterial activity of leaf and fruit extracts increased in proportion to the increase in concentration. Especially at high concentrations (16–32 %), the fruit extract showed a significantly stronger antibacterial effect compared to the leaf extract. The results obtained substantiate the high prospects of leaf and fruit extracts of A. melanocarpa grown in vitro as natural antibacterial agents and the possibility of their application in the pharmaceutical and biotechnology fields.