Grain amaranth is known as an alternative crop with exclusive nutritional value and health benefits. The purpose of this study was to investigate the effect of gamma irradiation on quantitative and qualitative amaranth seed traits, including 1000-seed weight, amino acids, fatty acids content, oil, and squalene yield. Two Slovak mutant varieties “Pribina” (A. cruentus) and “Zobor” (A.hypochondriacus x A. hybridus) were evaluated and compared to nonirradiated controls Ficha (A. cruentus L.) and K-433 (A. hypochondriacus x A. hybridus) and commercial varieties, Aztec (A. cruentus L.), Plainsman and Koniz (A. hypochondriacus x A. hybridus). Mutant varieties, “Pribina” and “Zobor”, showed superior 1000-seed weight performance compared to all investigated amaranth samples. The change in quantitative seed trait was accompanied by significantly higher oil and squalene content compared to commercial varieties. Moreover, significantly higher content of essential linoleic acid was detected in mutant variety “Zobor”. The present findings suggest that seeds of irradiation-derived varieties have high nutritional potential and can be used as a supplementary crop in the human diet.

Berry fruit species are, in many countries, considered biologically and economically valuable and important species of small fruits. The aim of this work was to examine the influence of either decreased or increased mesos concentrations (MgSO₄, CaCl₂, and KH₂PO₄) on shoot multiplication of five cultivars of three small fruit species (Amelanchier alnifolia var. cusickii, Rubus fruticosus ‘Black Satin’ and ‘Loch Ness’, and Vaccinium corymbosum ‘Brigitta Blue’ and ‘Toro’). Mesos nutrients were manipulated from half to four times their base concentration. The results indicate that mesos manipulation significantly influences the number and length of shoots in most of the studied cultivars. The greatest multiplication rate for A. alnifolia was achieved with tripled mesos, whereas ‘Black Satin’ and ‘Loch Ness’ reacted positively to a lower (1–2x) concentration of mesos. Decreasing the concentration of mesos to half led to worse quality in both blackberry and Saskatoon shoots. ‘Brigitta Blue’ was more sensitive to greater mesos concentrations compared to ‘Toro’. Optimizing the mineral nutrition of plants cultivated in vitro enhances their multiplication rate and contributes to a higher production of good quality plantlets.

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.

The aim of this work was to assess the regeneration capacity of Amelanchier alnifolia var. cusickii and Lonicera kamtschatica cv. ‘Jugana’ from different types of explants under various hormonal treatments. The whole leaves, petioles, and internodal segments of in vitro plants were examined as explants. Several plant growth regulators (cytokinins and auxins) were evaluated for their ability to induce adventitious regeneration. Direct and indirect organogenesis was achieved under certain culture conditions in both species. The frequency of shoot regeneration was strongly dependent on concentrations of plant growth regulators in the induction media (L.kamtschatica ‘Jugana’) or concentrations of plant growth regulators in the induction media and type of explant (A. alnifolia var. cusickii). Results showed that leaves were not suitable explants for A. alnifolia var. cusickii. Both species were able to regenerate shoots from internodal segments and petioles. The highest induction of shoots was obtained on Murashige and Skoog (MS) medium enriched with 2 mg/L thidiazuron (TDZ) and 0.5 mg/L indole-3-butyric acid (IBA) for Amelanchier alnifolia and with 1 mg/L TDZ and 0.2 mg/L indole-3-acetic acid (IAA) for L. kamtschatica ‘Jugana’. Obtained adventitious shoots were further proliferated in order to investigate their multiplication capacity. The multiplication of shoots was successful in all cultivars, with the best results reported in A. alnifolia var. cusickii (7.07 shoots/explant on average).