Typy publikací: Časopis

Commercial micropropagation plays a crucial role in increasing the production of many economically important fruit crops worldwide, including Europe. The focus has been on many woody horticultural species, such as stone and pome fruits, berries, nuts, and palms. This paper presents an updated overview of the European commercial micropropagation landscape, highlighting the countries currently operating in this sector, crop targets, and the distribution of micropropagation companies based on recent survey data.

Reforestation initiatives are often limited by insufficient seeds, a problem exacerbated by natural variability in tree flowering and seed production, climate change and other environmental challenges. Innovative and adaptive solutions, such as in vitro propagation, are thus needed. Tissue culture can provide high-quality propagation material for tree conservation and mass propagation, but faces technical, economic, regulatory, and social barriers.

It is assumed that the production of somatic embryos (SEs), which closely resemble fully mature zygotic embryos (ZEs), increases the chance of producing somatic plants equivalent to seedlings. Desiccation is crucial to reduce the water content of SEs and to initiate biochemical changes that support germination and conversion into plants. We investigated the biological, histological, biochemical and molecular changes in the SEs of hybrid larch Larix eurolepis exposed to desiccation at high relative humidity (RH; 98 %), reduced RH (59 %), or a combination of both.

Chenopodium ficifolium is a close diploid relative of the tetraploid crop Chenopodium quinoa. Owing to its reproducible germination and seedling development, it becomes a promising model for studying floral induction, providing a basis for comparison with C. quinoa. Two C. ficifolium genotypes differ in photoperiodic requirement: C. ficifolium 283 accelerates flowering under long days, whereas C. ficifolium 459 flowers earlier under short days.

Nowadays, when climate change is becoming more and more evident, drought stress plays a very important role, including in agriculture. The increasing number of years with extreme temperatures in the Czech Republic has a negative impact on agricultural production, among other things. Therefore, ways are being sought to reduce these negative impacts. One of them may be the use of compochar (a mixture of compost and biochar) to improve water retention in the soil.

The workflow enables the quantification of autophagosomes in Arabidopsis thaliana root epidermal cells in 3D. It combines immunolabeling of an autophagosome marker ATG8 with commercially available anti-ATG antibody and the subsequent stereological quantification of the immunolabeled particles. The immunolabeled samples are imaged with a confocal microscope and Z-stacks are acquired.

Macroautophagy is often quantified by live imaging of autophagosomes labeled with fluorescently tagged ATG8 protein (FP-ATG8) in Arabidopsis thaliana. The labeled particles are then counted in single focal planes. This approach may lead to inaccurate results as the actual 3D distribution of autophagosomes is not taken into account and appropriate sampling in the Z-direction is not performed.

The FLOWERING LOCUS T like 2–1 gene of Chenopodium ficifolium and Chenopodium quinoa acts as a strong activator of flowering in Arabidopsis, triggering flowering at cotyledon stage and causing lethality when overexpressed.

In Norway spruce, as in many other conifers, the germination capacity of somatic embryos is strongly influenced by the desiccation phase inserted after maturation. The intensity of drying during desiccation eminently affected the formation of emblings (i.e., seedlings developed from somatic embryos). Compared to non-desiccated embryos, the germination capacity of embryos desiccated at 100% relative humidity was about three times higher, but the reduction of relative humidity to 95% and 90% had a negative effect on the subsequent embryo development.

The transition from vegetative growth to reproduction is an essential commitment in plant life. It is triggered by environmental cues (day length, temperature, nutrients) and regulated by the very complex signaling gene network and by phytohormones. The control of flowering is well understood in Arabidopsis thaliana and in some crops, much less is known about the other angiosperms.