Cadmium (Cd) is a heavy metal that can cause damage to living organisms at different levels. Even at low concentrations, Cd can be toxic to plants, causing harm at multiple levels. As they are unable to move away from areas contaminated by Cd, plants have developed various defence mechanisms to protect themselves. Hyperaccumulators, which can accumulate and detoxify heavy metals more efficiently, are highly valued by scientists studying plant accumulation and detoxification mechanisms, as they provide a promising source of genes for developing plants suitable for phytoremediation techniques. So far, several genes have been identified as being upregulated when plants are exposed to Cd. These genes include genes encoding transcription factors such as iron-regulated transporter-like protein (ZIP), natural resistance associated macrophage protein (NRAMP) gene family, genes encoding phytochelatin synthases (PCs), superoxide dismutase (SOD) genes, heavy metal ATPase (HMA), cation diffusion facilitator gene family (CDF), Cd resistance gene family (PCR), ATP-binding cassette transporter gene family (ABC), the precursor 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and precursor 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) multigene family are also influenced. Thanks to advances in omics sciences and transcriptome analysis, we are gaining more insights into the genes involved in Cd stress response. Recent studies have also shown that Cd can affect the expression of genes related to antioxidant enzymes, hormonal pathways, and energy metabolism.

A plant microbiome is an important factor in plant growth, stress resistance, health status, and consumer quality and safety. The rhizosphere microbiome evolves in a negotiation between microbial communities that inhabit soil and plant root tissue. In this study, the rhizosphere and root internal tissue microbiome of six varieties of lettuce were analyzed in normal conditions and under salinity stress. The metabarcoding analysis used 16S rRNA gene and ITS2 region sequencing. The microbiomes of root samples were significantly less diverse with different members of the community compared to those of the rhizosphere. A significant effect of lettuce variety was found on the diversity index for bacteria and fungi. Varieties formed very different communities of bacteria in roots. Pseudomonas, Herbaspirillum, Mycobacterium, potentially pathogenic Enterobacter, and other genera were more prevalent in certain varieties. Salinity stress had a significant negative impact on bacterial diversity and community composition, whereas the diversity of fungi has not changed significantly, and the fungal community has changed less than the bacterial one. Changes were more evident in varieties that were more resistant to salinity stress than in sensitive varieties.

Citrus fruits enjoy widespread consumption globally, being among the most popular fruits. They are highly regarded for their nutritional composition, offering a range of beneficial nutrients. However, it is important to acknowledge that they can also elicit allergic reactions in sensitized individuals, which presents a contrasting aspect. The Bet v 1 cross-reacting allergen is a major birch pollen allergen, and it is the most commonly sensitizing allergen in central Europe. Bet v 1 belongs to the group of PR-10 proteins in the plant kingdom that cause various allergic reactions. The Bet v 1 allergen has a number of isoforms and homologs. These homolog genes are inherited from a common ancestor and subsequent amino acid similarity. They can cause the phenomenon of cross-reactivity in food allergies. The aim of the study was to analyze the length of polymorphism variability of the Bet v 1 homolog in orange varieties by using degenerated and nondegenerated primers. A total of eight varieties of Citrus sinensis L. Osbeck were used in the analysis. The BBAP technique (Bet v 1 based amplified polymorphism) was used to detect the length variability of fingerprints of allergen encoding genes of Bet v 1 homologs. Degenerated primer combinations and only one of the nondegenerated variants of primers provided fingerprints that were unique for every individual variety of analyzed oranges. By using other primer variants, from two up to the four varieties generated by the same BBAP profile, indicate a higher degree of Bet v 1 homolog sequential conservativity when compared to other fruit species.

Physiological and molecular marker-based changes were studied in the tissues of two-year-old Pyrus pyraster (L.) Burgsd. seedlings under salt treatment. For 60 days, 5 mL of 100 mM NaCl solution was applied to each plant per day to a cumulative volume of 300 mL in the substrate. In response to osmotic stress, the seedlings increased their water use efficiency (WUE) on day 20 of regular NaCl application and maintained a stable net photosynthetic rate (A_n) per unit area. Under conditions of increasing salinity, the young plants maintained a balanced water regime of the leaf tissues (Ψ_wl). The seedlings invested mass to their root growth (R/S), retained a substantial portion (72%) of Na⁺ ions in the roots, and protected their leaves against intoxication and damage. A significant decrease in the leaf gas exchange parameters (g_s, E, A_n) was manifested on day 60 of the experiment when the cumulative NaCl intake was 300 mL per plant. The variability in the reactions of the seedlings to salinity is related to the use of open-pollinated progeny (54 genotypes) in the experiment. Lus-miR168 showed tissue- and genotype-specific genome responses to the applied stress. Polymorphic miRNA-based loci were mostly detected in the root samples on the 20th and 35th days of the experiment. The cumulative effect of the salt treatment was reflected in the predominance of polymorphic loci in the leaves. We can confirm that miRNA-based markers represent a sensitive detection tool for plant stress response on an individual level. The screening and selection of the optimal type of miRNA for this type of research is crucial. The cytochrome P450-Based Analog (PBA) techniques were unable to detect polymorphism among the control and treated seedlings, except for the primer pair CYP2BF+R, where, in the roots of the stressed plant, insertions in the amplicons were obtained. The expression ratios of cytochrome P450 in the salt-stressed plants were higher in the roots in the case of 20/100 mL and in the leaves with higher doses. The observed physiological and molecular responses to salinity reflect the potential of P. pyraster seedlings in adaptation to osmotic and ionic stress.

Apples are a popular fruit worldwide, with many health and nutritional benefits. However, this fruit is also among those that, particularly in Central and Northern Europe, are allergenic due to the Mal d 1 allergen. Mal d 1 is a homologous allergen to Bet v 1—the main pollen allergen of birch. In this study, two different approaches were used to identify the natural length polymorphism of Bet v 1 homologs in apple varieties, with the aim of characterizing their effectiveness. BBAP (Bet v 1 based amplified polymorphism) and RFLP (restriction fragments length polymorphism) profiles were characterized and compared. RFLP analysis recognizes the genetic diversity of M. domestica Mal d 1 sequences at a relatively low level. In BBAP profiles, the genetic dissimilarity was up to 50%, which appears suitable for intraspecific fingerprinting and serves as an additional method for RFLP analysis. RFLP analysis was able to distinguish some varieties that BBAP could not, such as Sonet.

During evolution, plants have developed complex mechanisms to cope with biotic and abiotic stresses. The study of heavy metal-plant interactions, particularly at the molecular genetic level, helps to understand heavy metal accumulation in plants and their resistance to heavy metal-induced stress. Amaranthus spp. have a potential in phytoremediation techniques. In this study was analysed the effects of cadmium (Cd) treatment and Cd treatment with addition of silicon (Si) on Amaranthus hypochondriacus L. x Amaranthus hybridus L. var. Plainsman, in leaves, in the context of the molecular genomic response using two different DNA marker techniques such as cytochrome P450 mono-oxygenase analogues (PBA) and conserved DNA-derived polymorphism (CDDP) for WRKY genes. The PBA marker technique consists of several primers pairs that have been designed for cytochrome P450 genes, and CDDP primers pairs have been designed on conserved regions of DNA. Both marker techniques have been shown to be able to detect the response to biotic and abiotic stresses. We detected higher variability in genomic profile with the CDDP marker systems compared to PBA. However, the highest number of loci (169) we detected using the BF (forward primer) + BR (reverse primer) of PBA.