Jana Moravčíková, Denisa Margetínyová, Zdenka Gálová, Iwona Žur, Zuzana Gregorová, Mária Zimová, Eva Boszorádová and Ildikó Matušíková
The (1,3)-β-D-glucan also referred to as callose is a main component of cell walls of higher plants. Many physiological processes are associated with the changes in callose deposition. Callose is synthesised by the callose synthase complex while its degradation is regulated by the hydrolytic enzymes β-1,3-glucanases. The latter one specifically degrade (1,3)-β-D-glucans. This work is aimed to study β-1,3-glucanase activities in the leaves of plants at two leaf stage in two diploids (Agilops tauschii, Triticum monococcum L.), four tetraploids (Ae. cylindrica, Ae. triuncialis, T. araraticum, T. dicoccum) and two hexaploids (T. aestivum L, T. spelta L.). The leaves were subjected to qualitative and quantitative β-1,3-glucanase activity assays. Our results showed that the total β-1,3-glucanase activities were variable and genotype dependent. No significant correlation between β-1,3-glucanase activities and ploidy level was observed. The gel activity assays revealed a single fraction of ~52 kDa Glu1 that was found in all genotypes. The Glu1 fraction corresponds to a single or two acidic Glu isoforms in dependence on genotype. However, none of the acidic Glu fractions can be assigned as a specific for di-, tetra- or hexaploid genotypes. A single basic GluF isoform was detected and found as present in all genotypes.
Monika Bardáčová, Yevheniia Konotop, Zuzana Gregorová, Miroslav Horník, Jana Moravčíková, Ján Kraic and Ildikó Matušíková
Cadmium is a serious environmental pollutant and its uptake by plant represents a serious health risk. Uptake, accumulation as well as sensitivity of soybean plants to metals have been shown to vary with genotype, while the dynamics of this uptake has rarely been studied. Here we studied the uptake and accumulation of Cd2+ ions in different parts of soybean plants of four cultivars Moravians, Gallec, Kent and Cardiff. The plants at early developmental stage were immersed in Hoagland nutrient solution in the presence or absence of 50 mg.L−1 and the isotope of 109Cd2+ to monitor its accumulation continuously at 24 h intervals for 10 days. Our results showed that the uptake rate varied among the cultivars, being the highest in roots of the cv. Moravians and the lowest in the cv. Gallec. We also observed a non-even distribution of radioactivity within the entire plants of individual cultivars. The most of Cd2+ isotope was translocated into primary leaves and leaves in the cvs. Kent and Moravians; on the contrary, relatively less in the cvs. Cardiff and Gallec. The results were fitted with genetic potential, growth as well as defense parameters such as proline accumulation. Combining uptake dynamics and biochemical data are indicative for different tolerance strategies of soybeans.
Jana Sojková, Iwona Žur, Zuzana Gregorová, Mária Zimová, Ildikó Matušíková, Daniel Mihálik, Ján Kraic and Jana Moravčíková
This work is aimed to evaluate in vitro regeneration potential of seven commercial soybean varieties Bohemians, Cardiff, Gallec, Merlin, Moravians, Naya and Silensia (Glycine max L.) cultivated in Central Europe. Our results showed the half-seeds could be effectively used as an explant source for all tested cultivars. The regeneration was initiated on the media containing growth regulators 1.67 mg.l-1 BAP and 0.25 mg.l-1 GA3. Within the first five days culture, green chlorophyll-containing explants were observed with frequency from 18.3% to 55.9%. Two weeks later, the explants responded by production of calli with the efficiency up to 83.0%. First shoots appeared after 2–3 weeks of subculture on the media. The soybean regeneration showed to be genotype-dependent with variable efficiencies from 5.7% (cv. Naya) to 37.7% (cv. Gallec). The cultivars Cardiff, Merlin and Gallec appear to be the most promising candidates for further biotechnological use. Application of antioxidants such as L-cysteine, dithiothreitol and sodium thiosulfate does not have effect on the explant regeneration for the first five days.
Monika Bardáčová, Marína Maglovski, Zuzana Gregorová, Yevheniia Konotop, Miroslav Horník, Jana Moravčíková, Ján Kraic, Daniel Mihálik and Ildikó Matušíková
Cell walls represent the first barrier that can prevent the entrance of toxic heavy metals into plants. The composition and the flexibility of the cell wall are regulated by different enzymes. The ß-1,3-glucanases control the degradation of the polysaccharide callose as a flexible regulation mechanism of cell wall permeability and/or its ability to bind metals under stress conditions. The profile and activity of ß-1,3-glucanases in the presence of heavy metals, however, has rarely been studied. Here we studied these enzymes in four soybean varieties (Glycine max) grown in the presence of cadmium ions. These analyses revealed three acidic and one basic enzyme isoforms in each soybean variety, but only two of the acidic isoforms in the variety Moravians were substantially responsive to the presence of Cd2+. Since the responses of certain glucanases were detected mainly in the varieties sensitive to metal and accumulating high amounts of metals, we assume their role in the defense rather than strategic metal sequestration.
Jana Moravčíková, Nikoleta Ujvariová, Iwona Žur, Zdenka Gálová, Zuzana Gregorová, Mária Zimová, Eva Boszorádová and Ildikó Matušíková
Defense components such as chitinases (EC 18.104.22.168) are crucial for plants to cope diseases. Despite of that the pattern and activities of these enzymes in agronomically important Triticale is unexplored. This work is aimed to study chitinase activities in the leaves of plants of early developmental stages in two diploids (Aegilops tauschii Coss., Triticum monococcum L.), four tetraploids (Ae. cylindrical Host, Ae. triuncialis L., T. araraticum Jakubyz, T. dicoccum Schrank) and two hexaploids (T. aestivum L., T. spelta L.). The leaves were subjected to quantitative and qualitative activity assays using synthetic 4-methylumbelliferyl-β-D-N,N´,N´´-triacetylchitotrioside and glycolchitin as substrates, respectively. Our results showed that the activities of chitinases with specificity towards short oligomers were variable and genotype dependent. The enzyme activities in the tetra- and hexaploid genotypes were significantly higher than in diplod counterparts. In the gel detection assays were revealed up to four fractions (~20, 30, 42 and 95 kDa) of proteins with the chitinase activity towards long chain polymers. The isoform of ~30 kDa was identified in all analyzed genotypes. Among the seven acidic and three basic chitinase fractions identified, three acidic (ChiA, ChiB, ChiC) and two (ChiH, ChiI) fractions were present in all genotypes. None of the isoforms can be assigned as specific with respect to ploidy.