Grapes and strawberries are major fruit crops with a dynamic, fast-growing global market. In addition to conventional techniques, biotechnological tools allow the preservation of valuable genotypes of both crops and the large-scale propagation of high-quality material. We have developed new protocols for expeditious and reliable micropropagation of grapes and strawberries cultivated in south Russia. In vitro cultivation on semisolid media was combined with rapid propagation in bioreactors. A six-week cycle of propagation in a bioreactor resulted in a 300-fold increase in fresh mass, with a propagation rate of ~5 in grapes and ~20 in strawberries. Genetic analysis using the inter simple sequence repeat (ISSR) DNA fingerprinting technique confirmed the full uniformity of the regenerants. The results of this research will support the local horticultural industry with fast and efficient propagation systems of new breeding lines, introduced varieties, and elite cultivars.

Lemon wormwood Artemisia balchanorum was recently introduced to southern Russia as a new aromatic plant. Based on biological and chemical characteristics, several populations with dominant citral, linalool, and geraniol production were selected for further development and maintained by seed propagation. Chemical analysis of five outstanding populations at three stages of annual development: vegetative, flower buds, and full flowering, confirmed that the seed populations retain the distinct dynamics of the dominant and minor components during the annual cycle and can be used for the commercial production of citral, linalool, and geraniol. Micropropagation in vitro allows for efficient clonal micropropagation and mass reproduction of elite cultivars and promising forms of A. balchanorum on a commercial scale but cannot serve as a source of direct and efficient production of secondary metabolites.

The cultivation of micropropagated grapevine plants in vitro is currently undergoing improvements in existing methods and the development of new cultivation techniques due to the problem of bacterial contamination caused by multidrug-resistant microorganisms. Explants (Vitis vinifera L., ‘Chardonnay’ variety) were cultured on Murashige-Skoog basal medium supplemented with different concentrations of ceftriaxone: 0 mg/L, 250 mg/L, and 1000 mg/L. After 30 days, morphometric characteristics of the micropropagated plants and relative copy numbers of mitochondrial and chloroplast DNA were evaluated. Leaf samples (5-10 mg) were randomly selected from each plant group for subsequent total DNA extraction. Quantitative RT-PCR was performed using LightCycler 480 SYBR Green I Master Mix (LifeScience, Roche) and analyzed with a LightCycler 96 automated analyzer (Roche Life Science). The relative copy numbers of NAD1 (mitochondrial DNA) and rps16 (chloroplast DNA) genes were determined using the GAPDH gene (chromosomal DNA) as the reference. The 2-DCt and 2-DDCt algorithms were used for quantitative assessment. Ceftriaxone at concentrations of 250 and 1000 mg/l reduces the relative number of copies of chloroplast and mitochondrial DNA, which indicates the suppression of photosynthesis and oxidative phosphorylation in grape microplants. The experimental scheme developed by us can be successfully used as a test system for assessing the degree of influence of various biogenic and abiogenic factors on plant objects in order to optimize their cultivation.

In the context of global warming, studying the consequences of increased temperature on agricultural crops becomes important for predicting the shortand long-term impacts on productivity. The effects of elevated temperature on grapevine plants lead to increased yield losses in viticulture. Micropropagated grapevine plants of the ‘Chardonnay’ variety were grown in vitro on MS medium and subjected to heat treatment at 45°C for 120 minutes. The control group of plants was not exposed to heat treatment. The levels of relative copy numbers of chloroplast and mitochondrial DNA were determined in leaf tissues of all plant groups using the RT-PCR method 30 days after heat treatment. In the group of plants subjected to heat treatment, statistically significant (p>0.05) reductions in the relative copy numbers of mitochondrial and chloroplast DNA were observed compared to the control group, with a decrease of over 30%. The copy number of chloroplast DNA exceeded that of mitochondrial DNA by more than 20 times in both the experimental and control groups. Heat treatment of micropropagated grapevine plants in vitro resulted in a closer correlation (r=+0.86) in the regulation of activity between these organelles, alongside the decrease in relative copy numbers of both mitochondrial and chloroplast DNA. This study demonstrates the promising use of relative copy numbers of chloroplast and mitochondrial DNA in plant leaves to investigate their potential physiological response to adverse environmental factors.

The copy number of DNA matrices of subcellular organelles (plants) can serve as an indicator of the intensity of photosynthesis and oxidative phosphorylation processes. We assessed the relative copy numbers (RCN) of mitochondrial and chloroplast DNA in young and mature leaves of three grape varieties: ‘Traminer Pink’, ‘Chardonnay’, and ‘Syrah’, grown under field conditions. Leaf samples (5–10 mg) were randomly selected from each group of plants for subsequent total DNA extraction. The qRTPCR reaction was performed using LightCycler 480 SYBR Green I Master Mix (LifeScience, Roche) and a LightCycler 96 Automatic Analyzer (Roche Life Science). The relative copy numbers of the NAD1 gene (mitochondrial DNA) and rps16 gene (chloroplast DNA) were determined using the GAPDH gene (chromosomal DNA) as a reference. Quantitative assessment was conducted using the 2--Ct и 2---Ct algorithms. It has been established that the relative copy number (RCN) values of chloroplast and mitochondrial DNA vary and depend on the grape variety and leaf maturity. RCN of chloroplast and mitochondrial DNA is significantly higher in mature grape leaves of all studied varieties, indicating a higher intensity of photosynthesis and oxidative phosphorylation in mature grape leaves compared to young leaves. When assessing the MacroErgic Balance (MEB) indicator, it can be concluded that from 2 to 4% of the energy obtained in chloroplasts through photosynthetic processes is used for the production of macroergic compounds in the mitochondria of various grape varieties in both young and mature leaves. The experimental scheme we have developed can be successfully used as a testing system to assess the potential yield of various grape varieties.