Influence of Abiotic Stress Factors on the Antioxidant Properties and Polyphenols Profile Composition of Green Barley (Hordeum vulgare L.).

The influence of stress factors on the plant can, on the one hand, lead to worse functioning of the plant and loss of its crop, but on the other, it can have a positive effect on the metabolism of compounds with documented biological activity. In this study, the effect of light and drought intensity on photosynthetic activity and physiological status of two barley varieties, as well as the antimicrobial, antioxidant properties and profile of polyphenolic compounds of green barley were analysed. It was shown that under the conditions of water shortage, the KWS Olof variety showed a smaller decrease in CO2 assimilation and transpiration and higher values of these parameters at both light intensities. Only in the KWS Olof variety increased stress as a result of increased light intensity. It has also been shown that both the intensity of radiation and drought-related stress have a significant impact on the profile of polyphenolic compounds from green barley, without a simple relationship between the impact of stress factors on the content of polyphenols. Changes in the profile of polyphenolic compounds augmented the antioxidant and antimicrobial activity of the material. This, in turn, proposes the possibility of reducing the applied doses of herbal material thanks to a greater content of active substances in extracts obtained from the plants used to produce medicinal preparations.

Succinate dehydrogenase inhibitor seed treatments positively affect the physiological condition of maize under drought stress.

Improvements in agricultural production are needed, as the growing human population demands more resources and exerts stronger effects on climate. Water scarcity is one of the main factors limiting the yield of maize in many regions of the world. One possible method to mitigate the negative effects of drought is seed mortars; its use improves plant development from the early stages onwards. In this study, we tested 12 various seed treatments with and without succinate dehydrogenase inhibitors (SDHI; sedaxane) on maize "SY Fanatic." Physiological parameters of germinating seeds, of young maize seedlings under drought, and of seedlings recuperated from drought were assessed and compared across 12 seed treatments and with non-stressed plants. The seed treatments varied greatly in their influence on the germination and the physiological state of seedlings under drought and after regeneration. Seeds under treatments No. 6, 11, and 12 showed the highest germination energy (97.3%). The use of SDHI-containing seed treatments significantly improved the development of the maize root system. The longest roots, ~13 cm in length, were recorded for treatments No. 6 and 12, both containing sedaxane. These treatments also boosted the functioning of plants growing under optimal soil moisture conditions and under drought stress, influencing the photosynthesis process, increasing the absorption of CO2, and improving the parameters of chlorophyll fluorescence in relation to non-treated controls. Our data indicated that using substances from the SDHI group can possibly reduce the drought-related stress reactions in maize, helping this important crop to face the progressing climate change.

Technological and antioxidant properties of proteins obtained from waste potato juice.

The article presents the technological and antioxidant properties of potato juice (PJ) protein concentrate obtained by the novel ultrafiltration method. Commercial products, obtained from waste PJ by the traditional method of acid coagulation of proteins, were studied for comparison. Functional properties such as water or oil absorption, foaming capacity, and foam stability (FS) as well as solubility at various pH were assessed. Moreover, the total phenolic compound content, antioxidant activity, and mineral composition were determined. The results showed that PJ protein concentrate obtained by ultrafiltration has good oil absorption properties (6.30 mL/g), which is more than two times higher than the commercial proteins used in the comparison (P2 = 2.33 mL/g and P3 = 2.67 mL/g). Moreover, the ability to create and stabilize foam was also higher (FS ranging from 20.0% at pH = 10 to 11.3% at pH = 2 after 60 min of testing). It had higher content of macro- and microelements and antioxidant activity compared to other samples. Therefore, it is possible to obtain interesting potato protein concentrate from the waste product of the starch production process, which may be an interesting raw material for enriching food.

Selection of Parental Material to Maximize Heterosis Using SNP and SilicoDarT Markers in Maize.

The chief aim of plant breeding is to improve varieties so as to increase their yield and breeding traits. One of the first stages of breeding is the selection of parental forms from the available gene pool of existing varieties. To date, costly and laborious methods based on multiple crossbreeding and phenotypic selection have been necessary to properly assess genetic resources in terms of productivity, quality parameters, and susceptibility to biotic and abiotic stressors. The often long and complicated breeding cycle can be significantly shortened through selection using DNA markers. To this end, use is made of close couplings between the marker and the locus responsible for the inheritance of the functional trait. The aim of this study was to identify single nucleotide polymorphism (SNP) and SilicoDArT markers associated with yield traits and to predict the heterosis effect for yield traits in maize (Zea mays L.). The plant material used in the research consisted of 19 inbred maize lines derived from different starting materials, and 13 hybrids resulting from crossing them. A two-year field experiment with inbred lines and hybrids was established at two Polish breeding stations on 10 m2 plots in a randomized block design with three replicates. The biometric measurements included cob length, cob diameter, core length, core diameter, number of rows of grain, number of grains in a row, mass of grain from the cob, weight of one thousand grains, and yield. The isolated DNA was subjected to DArTseq genotyping. Association mapping was performed in this study using a method based on the mixed linear model with the population structure estimated by eigenanalysis (principal component analysis of all markers) and modeled by random effects. Narew, Popis, Kozak, M Glejt, and Grom were the hybrids used in the study that showed the highest significant heterosis effect in 2013 and 2014. The similarity between parental components determined on the basis of SNP and SilicoDArT marker analysis did not exceed 33%. It was found that the genetic similarity between parental components, determined on the basis of SNP and SilicoDArT markers, reflected their degree of relationship, and correlated significantly with the effect of heterosis. As the results indicate, the parental components for heterosis crosses can be selected based on genetic similarity between parental components evaluated using SNP and SilicoDArT markers, supported with information on the origin of parental forms. Of the markers we analyzed, 76 were selected as being significantly associated with at least six traits observed in 2013 and 2014 at both the Lagiewniki and Smolice stations.

Identification of Leaf Rust Resistance Genes in Selected Wheat Cultivars and Development of Multiplex PCR.

Ten leading wheat cultivars originating from the Plant Breeding and Acclimatization Institute (IHAR) - National Research Institute (Poland) and the Department of Gene Bank (Czech Republic) were used to establish a field experiment in 2017 and 2018 at the Dlon Experimental Farm. The analyzed wheat genotypes were characterized by diversified field resistance to leaf rust. Jubilatka, Thatcher and Sparta were the most resistant cultivars in field conditions in both 2017 and 2018. The aim of the work was to identify the Lr11, L13, Lr16 and Lr26 genes encoding resistance to leaf rust using molecular SSR markers (wmc24, wmc261, Xgwm630, Xwmc764 and P6M12) and to develop multiplex PCR conditions to accelerate identification of these genes. Markers of three leaf rust resistance genes have been identified simultaneously in these cultivars. Jubilatka, Thatcher and Sparta cultivars may serve as a good source of the analyzed leaf rust resistance genes. In addition, multiplex PCR conditions have been developed for the simultaneous identification of the Lr11 and Lr16 and Lr11 and Lr26 gene pairs.

Chemical Profile and Antioxidant Activity of Trollius Europaeus under the Influence of Feeding Aphids.

The influence of stress factors on a plant may lead to worse functioning of the plant and the loss of its crop. The effect of Aulacorthum solani feeding on Trollius europaeus with regard to active compounds in the leaves was investigated in the study. The antioxidant activity of the leaves, the material on which the insects fed, was compared with that of the material that was not infested by the aphids. Stress level was evaluated on the basis of such physiological parameters as chlorophyll fluorescence and photosynthesis activity. An increase of 34.5% in the content of polyphenolic compounds, as compared to control, was demonstrated in the material exposed to the biotic stress caused by aphids. The content of phenolic acids was 28% higher while that of flavonoids rose by 25%. The increase in polyphenolic compounds augmented the antioxidant activity of the material.

Regulation of proline biosynthesis and resistance to drought stress in two barley (Hordeum vulgare L.) genotypes of different origin.

Drought is considered the main abiotic stress factor that inhibits growth of crop plants (including barley), limiting yield in many regions worldwide. Predicted climate changes show that in future the frequency and intensity of drought events will rise, so crops that are resistant to this stress are in demand. One of the adaptive metabolic responses to drought is the accumulation of proline. The aim of this study was to examine the effect of 10-day drought on tissue dehydration and proline biosynthesis in leaves as well as in roots of barley genotypes of different origin: the Syrian breeding line Cam/B1/CI and the German cultivar Maresi. The involvement of Δ1 pyrroline-5-carboxylate synthetase (P5CS), the expression of the P5CS gene and ABA in proline synthesis under drought were also studied. Finally, we examined the resistance of tested genotypes to applied drought using chlorophyll fluorescence parameters and above-ground dry matter accumulation. Drought caused a gradual decrease of water content and an increase of proline and ABA content in roots and leaves of both genotypes. A statistically significant positive correlation between proline accumulation and activity of P5CS was also revealed. The skyrocketing increase of P5CS activity and proline accumulation was proceeded by transcriptional up-regulation of P5CS. The relationships between changes in P5CS expression, P5CS activity and ABA content show that the latter compound is involved in drought-induced proline synthesis at the transcription and enzyme activity level. The examined barley genotypes were equally resistant to applied moderate drought stress regardless of the differences in the level of proline accumulated.