The process of uptake and translocation of non-organic iodine (I) ions, I^– and IO₃^–, has been relatively well-described in literature. The situation is different for low-molecular-weight organic aromatic I compounds, as data on their uptake or metabolic pathway is only fragmentary. The aim of this study was to determine the process of uptake, transport, and metabolism of I applied to lettuce plants by fertigation as KIO₃, KIO₃ + salicylic acid (KIO₃+SA), and iodosalicylates, 5-iodosalicylic acid (5-ISA) and 3,5-diiodosalicylic acid (3,5-diISA), depending on whether additional fertilization with vanadium (V) was used. Each I compound was applied at a dose of 10 μM, SA at a dose of 10 μM, and V at a dose of 0.1 μM. Three independent 2-year-long experiments were carried out with lettuce; two with pot systems using a peat substrate and mineral soil and one with hydroponic lettuce. The effectiveness of I uptake and translocation from the roots to leaves was as follows: 5-ISA > 3,5-diISA > KIO₃. Iodosalicylates, 5-ISA and 3,5-diISA, were naturally synthesized in plants, similarly to other organic iodine metabolites, i.e., iodotyrosine, as well as plant-derived thyroid hormone analogs (PDTHA), triiodothyronine (T3) and thyroxine (T4). T3 and T4 were synthesized in roots with the participation of endogenous and exogenous 5-ISA and 3,5-diISA and then transported to leaves. The level of plant enrichment in I was safe for consumers. Several genes were shown to perform physiological functions, i.e., per64-like, samdmt, msams5, and cipk6.

Iodine (I) is considered a beneficial element or even micronutrient for plants. The aim of this study was to determine the molecular and physiological processes of uptake, transport, and metabolism of I applied to lettuce plants. KIO₃, KIO₃ + salicylic acid, 5-iodosalicylic acid and 3,5-diiodosalicylic acid were applied. RNA-sequencing was executed using 18 cDNA libraries constructed separately for leaves and roots from KIO₃, SA and control plants. De novo transcriptome assembly generated 1937.76 million sequence reads resulting in 27,163 transcripts with N50 of 1638 bp. 329 differentially expressed genes (DEGs) in roots were detected after application of KIO₃, out of which 252 genes were up-regulated, and 77 were down-regulated. In leaves, 9 genes revealed differential expression pattern. DEGs analysis indicated its involvement in such metabolic pathways and processes as: chloride transmembrane transport, phenylpropanoid metabolism, positive regulation of defense response and leaf abscission, and also ubiquinone and other terpenoid-quinone biosynthesis, protein processing in endoplasmic reticulum, circadian rhythm including flowering induction as well as a putative PDTHA (i.e. Plant Derived Thyroid Hormone Analogs) metabolic pathway. qRT-PCR of selected genes suggested their participation in the transport and metabolism of iodine compounds, biosynthesis of primary and secondary metabolites, PDTHA pathway and flowering induction.

Iodine is a crucial microelement for humans, and iodine deficiencies may be reduced through the consumption of iodine-enriched plants. The possible effects of exogenous bromine regarding plant growth, iodine biofortification efficiency, and the chemical composition of cultivated plants have not been previously evaluated. A two-year pot cultivation of dandelion was conducted, applying KBr and KIO₃ in the following combinations: (1) Control, (2) 10 µM I, (3) 50 µM I, (4) 10 µM Br, (5) 50 µM Br, (6) 10 µM I + 10 µM Br, and (7) 50 µM I + 50 µM Br. An increased plant biomass indicated the low toxicity of the tested doses of I and Br for dandelion. However, a slightly increased antioxidant capacity in the leaves and roots and higher proline content in the leaves may suggest a potential stress effect of iodine and/or bromine accumulation for plants. The Br:I ratios observed in biofortified leaves and roots indicate the need to monitor bromine levels in soils or substrates used for plant cultivation in order to reduce the risk of excessive Br contents in iodine-enriched plants.

Cold storage of pelargonium cuttings addresses the issue of nonoverlapping production seasons in Central Europe, where cuttings are harvested from stock plants in December, but rooting begins in mid-February/March. Here, we show an innovative system for cuttings storage using nature-based solutions. We compared post-delivery storage of unrooted cuttings in paperpots maintained in greenhouses (8/6 °C day/night) to standard rooting immediately after delivery. Key factors included genotype (Pelargonium zonale, P. peltatum, and hybrids), four delivery weeks (48–51), two growing seasons (2021 and 2022), and storage duration (up to 4 weeks). Genotype strongly influenced cold storage tolerance, with P. peltatum enduring storage for up to 4 weeks without significant loss of rooting efficiency, unlike P. zonale. The success of storage depended on stock plants’ quality and nutritional status: higher nitrogen content in 2022 cuttings compared to 2021 was associated with reduced rooting in P. zonale and hybrids. Neither delivery timing nor residual ethephon affected rooting outcomes after storage. This study demonstrates that storing pelargonium cuttings for up to two weeks using this method preserves quality while optimizing production efficiency by reducing nursery space, water, fertilizer, and pesticide use. This shift in production practices reduces per-unit costs and enhances the economic viability of bedding young plant producers.