Allium cepa root meristem cells under osmotic (sorbitol) and salt (NaCl) stress in vitro

The effects of various concentrations of sorbitol (100, 200 and 360 mM) and NaCl (100, 200 and 300 mM) on root meristem cells of in vitro-cultured Allium cepa L. were analyzed after 10 and 20 days. Both root meristem cell cross-section area and nuclear volume decreased under osmotic and salt stress. The osmotic component of applied stresses had a greater impact on cell shrinkage, while ionic stress perturbed cell functioning, resulting in cell cycle arrest and various aberrations, affecting nucleus integrity. A concentration of 300 mM of NaCl in the culture medium caused complete inhibition of mitotic activity in onion root tip cells after 20 days of exposure. Analysis of the action of iso-osmotic concentrations of NaCl (200 mM) and sorbitol (360 mM) showed stronger mitodepressive effects of salt stress in comparison to osmotic stres

Early studies on the effect of peptide growth factor phytosulfokine-α on Brassica oleracea var. capitata L. protoplasts

Phytosulfokines (PSK) are peptidyl growth factors with the potential of inducing cell proliferation. We examined the effect of supplementation of liquid culture medium with 0.1 µM phytosulfokine-α (PSK-α) on protoplast viability and division frequencies in seven accessions of Brassica oleracea var. capitata L., including cultivars and breeding lines. Protoplasts were isolated from leaves and hypocotyls of in vitro grown plants and immobilized in calcium-alginate layers. Cabbage protoplast-derived cells cultured in medium supplemented with 0.1 µM of PSK-α had higher viability and division frequencies compared to cells cultured in PSK-α-free control medium. The effect of PSK-α was more pronounced in low-responding accessions (‘Sława z Gołębiewa’, ‘Ramkila F1’, LM, and LM98); however, in two cultivars with very low response (‘Badger Shipper’ and ‘Oregon 123’), although the division frequencies in the media supplemented with PSK-α were increased over the control, the differences were not significant. Obtained callus colonies were subjected to regeneration. PSK-α supplemented into the liquid culture medium had an indirect effect on shoot regeneration by inducing sustained cell divisions leading to an increase in shoot regeneration in Sława z Gołębiewa and both breeding lines

Pollen Development and Stainability in <i>Vicia faba</i> L. and <i>Lupinus angustifolius</i> L.

Commercially, leguminous crops (Fabaceae) are the second most important group of cultivated plants, just after grasses (Poaceae). This study focuses on the analysis of pollen development and stainability in two species belonging to the Fabaceae family: Vicia faba L. and Lupinus angustifolius L. Morphological analysis of the anthers at various stages of flower development allowed us to trace the processes of microsporogenesis and microgametogenesis. Nine different cell staining protocols with diverse mechanisms of action, including acetocarmine, Alexander’s dye, aniline blue in lactophenol, Calcein AM, FDA, MTT, TTC, Lugol’s iodine, and aceto-orcein, were tested for their suitability in assessing the viability of microspores as well as pollen grains in both species. Among the applied dyes, four allowed for the discrimination between viable and nonviable microspores in V. faba, and six dyes allowed for this in L. angustifolius. For mature pollen grains, all dyes enabled differentiation between viable and nonviable cells in both species. The highest viability indications for V. faba microspores were obtained with acetocarmine (94.6%), while for mature pollen, aniline blue in lactophenol, MTT, and aceto-orcein yielded the highest viability indications (90.8–96.3%). In L. angustifolius, the highest percentages of viable microspores (64.9–66.5%) were obtained with the acetocarmine, aniline blue in lactophenol, and TTC dyes. For mature pollen, the highest viability indications (83.4%–92.9%) were obtained with acetocarmine, aniline blue in lactophenol, Lugol’s iodine, and aceto-orcein. The viability of V. faba pollen grains in an in vitro germination test showed that the highest pollen germination (61.3%) was observed on the BK medium (rich in minerals with 10% sucrose). In L. angustifolius, the highest pollen germination was observed on the media containing boric acid and 5% sucrose (70.5%) and on the medium containing 10% sucrose only (74.2%)

FLOWS OF CARE BETWEEN MIGRANTS AND THEIR AGEING PARENTS – RESEARCH METHOD AND AN EXAMPLE OF ITS IMPLEMENTATION

W konsekwencji obserwowanych procesów starzenia się społeczeństwa i wzmożonej mobilności przestrzennej następują przemiany relacji rodzinnych dotyczących opieki nad osobami starszymi. W rodzinach transnarodowych przestrzenny dystans zmusza członków rodzin do wypracowywania nowych, często skomplikowanych strategii działania. Złożoność problematyki związanej z opiekuńczością sprawia, że analiza funkcjonujących wzorców wymaga szczególnego podejścia badawczego. W artykule prezentujemy propozycję metody badawczej: wielostanowiskowe, transnarodowe badanie wykorzystujące mieszane techniki – analizy monograficzne, sondaż oraz wywiady pogłębione realizowane zarówno z osobami starszymi mieszkającymi w Polsce, jak i z członkami ich rodzin przebywającymi zagranicą. Zaprezentowane przykładowe wyniki przeprowadzonych badań ukazują użyteczność podejścia, które umożliwia ujawnienie i zbadanie złożonych relacji związanych z przepływami opieki.Ageing and intensive transborder mobility transforms family relations concerning elderly care. As a result of spatial distance, members of transnational families work out new, complex strategies. Complicated care arrangements require a special research approach which is the subject of this article. The research method the authors propose is a multisited, transnational study that combines mixed techniques: monographic analyses, a survey, and in-depth interviews, carried out both with the elderly people living in Poland and with their migrant relatives residing abroad. Selected results of the study reveal complex relations related to the flows of care and demonstrate the usefulness of the proposed research approach