Barley cultivar Amulet was used to study the quantitative proteome changes through different drought conditions utilizing two-dimensional difference gel electrophoresis (2D-DIGE). Plants were cultivated for 10 days under different drought conditions. To obtain control and differentially drought-treated plants, the soil water content was kept at 65, 35, and 30% of soil water capacity (SWC), respectively. Osmotic potential, water saturation deficit, ¹³C discrimination, and dehydrin accumulation were monitored during sampling of the crowns for proteome analysis. Analysis of the 2D-DIGE gels revealed 105 differentially abundant spots; most were differentially abundant between the controls and drought-treated plants, and 25 spots displayed changes between both drought conditions. Seventy-six protein spots were successfully identified by tandem mass spectrometry. The most frequent functional categories of the identified proteins can be put into the groups of: stress-associated proteins, amino acid metabolism, carbohydrate metabolism, as well as DNA and RNA regulation and processing. Their possible role in the response of barley to drought stress is discussed. Our study has shown that under drought conditions barley cv. Amulet decreased its growth and developmental rates, displayed a shift from aerobic to anaerobic metabolism, and exhibited increased levels of several protective proteins. Comparison of the two drought treatments revealed plant acclimation to milder drought (35% SWC); but plant damage under more severe drought treatment (30% SWC). The results obtained revealed that cv. Amulet is sensitive to drought stress. Additionally, four spots revealing a continuous and significant increase with decreasing SWC (UDP-glucose 6-dehydrogenase, glutathione peroxidase, and two non-identified) could be good candidates for testing of their protein phenotyping capacity together with proteins that were significantly distinguished in both drought treatments.

The objective of this work was to induce and detect somaclonal variation in arracacha (Arracacia xanthorrhiza) plants regenerated via indirect morphogenesis, in order to evaluate the potential of this technique to produce new genotypes for breeding purposes of this crop. Calli were induced from petiole segments on Murashige & Skoog (MS) medium supplied with 0.1 mg L-1 2,4-dichlorophenoxyacetic acid. The regeneration of plants via indirect morphogenesis was carried out on half-strength MS medium without plant growth regulators. Fifteen randomly chosen plants were subjected to flow cytometry and “inter-simple sequence repeat” (ISSR) analysis. Ploidy level remained stable in all tested regenerants (2n=4x=44), with no changes in the genome. Eighteen ISSR primers produced a total of 1,584 fragments in all samples. Two ISSR primers produced four polymorphic fragments in 26.7% of the tested samples. Somaclonal variation in arracacha is a result of plant regeneration via indirect morphogenesis and can be detected by ISSR markers.

The main biochemical traits were estimated in poplar leaves under biotic attack (aphids and spongy moth infestation). Changes in the abundance of bioactive compounds in genetically uniform individuals of European aspen (Populus tremula), such as proline, polyphenolic compounds, chlorophylls a and b, and volatile compounds, were determined between leaves damaged by sucking insects (aphid—Chaitophorus nassonowi) and chewing insects (spongy moth—Lymantria dispar) compared to uninfected leaves. Among the nine analyzed phenolic compounds, only catechin and procyanidin showed significant differences between the control leaves and leaves affected by spongy moths or aphids. GC-TOF-MS volatile metabolome analysis showed the clear separation of the control versus aphids-infested and moth-infested leaves. In total, the compounds that proved to have the highest explanatory power for aphid-infested leaves were 3-hexenal and 5-methyl-2-furanone, and for moth-infested leaves, trans-α-farnesene and 4-cyanocyclohexane. The aphid-infested leaves contained around half the amount of chlorophylls and twice the amount of proline compared to uninfected leaves, and these results evidenced that aphids influence plant physiology more than chewing insects.

With the gradual decline in the proportion of spruce as the most important tree species in the Czech Republic, the importance of pine will increase. The test material for this study was selected from two localities with important representation of pure Scots pine stands. Two stands, representing clear-cutting and shelterwood regeneration methods were selected from each locality. In the case of shelterwood method, tree samples from a lower layer were cut down and subsequently evaluated in terms of the impact of the regeneration method on the density of the wood, the density of earlywood and latewood, the proportion of latewood and the width of the annual rings. These qualitative parameters of the wood were compared before and after the release of the parent stand canopy. The clear-cutting regeneration method served as a reference. The values obtained before the release of the parent stand canopy are significantly different from values after its removal (share of latewood 47.7% and 48.1% before the release in contrast to 39.5% and 39.1% after the release for the locality 1 and the locality 2 respectively). The shelterwood regeneration method has not a significant impact on the overall investigated characteristics. Most significant was the impact of the regeneration method on the distribution of properties along the trunk radius, where the shelterwood method shows a uniform density distribution from the pith to the bark. From the view of industry, therefore, it is not important for the final processing which part of the trunk the wood comes from.

Ojcow birch (Betula oycoviensis Besser) is a rare Central European tree taxon, micro-populations of which are found in only several localities. With a view to maintaining the B. oycoviensis gene pool, this study tested the species’ potential for micropropagation, grafting, and propagation by cuttings. Plant material for vegetative propagation was collected from ten genotypes in the Czech Republic. In vitro culture was established from axillary buds surfaces sterilized with 0.1% HgCl2 and cultivated on woody plant (WP) medium supplemented with 1 mg l-1 6-benzylaminopurine (BAP). Two genotypes of the species were successfully multiplied by in vitro propagation using WP medium supplemented with 0-2 mg l-1 BAP. The BAP concentration of 1 mg l-1 proved to be optimal, yielding 2.5 new shoots per explant in genotype 516 and 3.5 shoots per explant in genotype 545. The shoots were rooted on half-strength Murashige and Skoog (MS) medium supplemented with various concentrations of α-naphthylacetic acid (NAA) and indole-3-butyric acid (IBA). The highest rooting percentages (72.5% and 77.5% for genotypes 516 and 545, respectively) were achieved on the medium with the combination of both auxins at concentrations of 0.3 mg l-1. The rooted plants were transferred ex vitro in substrate composed of sand, peat, and perlite (1:1:1) and acclimated in the greenhouse. After 4 weeks, more than 90% of plants survived. Grafting was carried out in spring using Betula pendula as rootstock. The efficiency of this technique ranged from 0% to 50% across genotypes, and 4 out of 10 genotypes were successfully propagated by grafting. The cuttings were treated with commercial root stimulators Stimulax I and Stimulator AS-1, planted in a mixture of peat and sand (1:1) in the greenhouse, and watered regularly. This technique resulted in 0% rooting, however, and no cutting survived until the end of the vegetation period. The results of this study show that protocols for in vitro propagation and grafting can be employed for effective mass propagation of B. oycoviensis, although these processes show genotype-dependent responses.