K. Pazderů

Effect of peeling and three cooking methods on the content of selected phytochemicals in potato tubers with various colour of flesh

The impact of peeling and three cooking treatments (boiling, baking and microwaving) on the content of selected phytochemicals in white-, yellow-, red- and purple-fleshed potatoes was investigated. Ascorbic acid and chlorogenic acid contents were determined by HPLC-DAD, total anthocyanin content by pH-differential spectrophotometry, glycoalkaloid, α-chaconine and α-solanine contents by HPLC-ESI/MS/MS. All cooking treatments reduced ascorbic and chlorogenic acid contents, total glycoalkaloids, α-chaconine and α-solanine with the exception of total anthocyanins. The losses of ascorbic and chlorogenic acids were minimised with boiling and total anthocyanin levels retained the highest. Boiling of peeled tubers decreased contents of total glycoalkaloids (α-chaconine and α-solanine) and appeared as the most favourable among the three tested methods. Moreover, due to higher initial levels, red- and purple-fleshed cultivars retained higher amounts of antioxidants (ascorbic acid, chlorogenic acid and total anthocyanin) after boiling and may be healthier as compared with white or yellow cultivars.

Changes in the content of various Fusarium mycotoxins forms in germinating winter wheat and spring barley kernels

Fusarium mycotoxins are frequent contaminants in cereals at temperate zone. Next to deoxynivalenol (DON), there are other masked forms of DON, deoxynivalenol-3-glucoside (D3G) or 3(15)-acetyl-deoxynivalenol (3(15)-ADON), but changes among these forms are still insufficiently known. All these forms were evaluated in germinating kernels of wheat and malting barley from deliberated inoculated field plots. Results showed possible occurrence of high ini tial content of all evaluated DON forms. Total contents of all forms were detected as very steady from start to end of the germination process. It suggests high importance of evaluating not only DON content, but all DON forms simultaneously.

Effect of cultivar, flesh colour, locality and year on carotenoid content in potato tubers

In this study, twelve cultivars of potato with different flesh colour (yellow, purple and red) were cultivated in 2012 and 2013 in two trial localities in the Czech Republic and evaluated for the main individual carotenoids. The con tent of total carotenoids (TC) in analysed cultivars ranged in 1.1–12.2 mg/kg in dry matter (DM) and was influ enced by genotype cultivar, locality and year. Cv. Agria (yellow flesh) reached 1.8 to 11.8 times higher levels of TC compared with cultivars of coloured flesh. Locality and year of higher average temperatures during the growing season produced higher TC contents in tubers. Genotype significantly influenced the content and composition of individual carotenoids. As in cv. Agria, violaxanthin (41%) and lutein (55–78%) dominated in all cultivars with coloured flesh. The relative content of β-carotene in cv. Agria represented 2% of TC, in cultivars with coloured flesh 5–12% TC.

Yield potential and antioxidant activity of potatoes with coloured flesh

In the experiment yield potential and antioxidant activity (AOA) of 13 potato cultivars with different flesh colour (purple (p); red (r); yellow (y) and white (w)) were evaluated at two localities with different environmental condi tions in three years 2009–2011. Yield potential was evaluated at harvest time in physiological maturity of crop stand. The results confirm that total yield and yield of tubers > 40 mm of coloured potatoes cvs. Red Emmalie/r (68.98 t/ha), Blaue Elise/p (59.96 t/ha), Valfi/p (53.72 t/ha) were comparable with control cvs. Agria/y, Lady Balfour/w and Russet Burbank/w. Some cultivars with lower yield had share of tubers above 40 mm comparable with control cultivars (94.45% and 93.48% in case of cvs. Valfi/p and Blue Congo/p), respectively. Antioxidant activity was determined as ascorbic acid equivalent by ABTS (2,2´-azinobis (3-ethylbenzothiazoline-6-sulfonate) method. The lowest antioxidant activity was observed in the control cvs. Lady Balfour/w (ascorbic acid equivalent (AAE) 74.1 mg/kg fresh mattter (FM)), Agria/y (AAE 84.4 mg/kg FM) and Russet Burbank (AAE 93.9 mg/kg FM). In the group of cultivars with red flesh AOA was 3.2 to 5.1 times higher and in a group of purple-fleshed cultivars it was from 3.7 to 7.0 times higher.

Importance of plant integrity in crop research, breeding, and production

Plant integrity looks like a “very easy and expanded topic,” but the reality is totally different. Thanks to the very high specialization of scientists, we are losing a holistic view of plants and are making mistakes in our research due to this drawback. It is necessary to sense a plant in their whole complexity—in both roots and shoot, as well as throughout their life cycles. Only such an integrated approach can allow us to reach correct interpretations of our experimental results.

Effect of Fusarium spp. Contamination on Baking Quality of Wheat

The effect of Fusarium spp. contamination on baking quality of winter common wheat and spelt wheat from different growing systems (organic and conventional) was evaluated by the standard technological quality characteristics and by the rheological system Mixolab. The content of Fusarium spp. mycotoxins [deoxynivalenol (DON), deoxynivalenol-3-βd-glucoside (D3G), 3-acetyldeoxynivalenol (3-ADON), and Zearalenones (ZON)] was determined too. Significantly worse standard technological quality parameters and rheological parameters were determined for artificially inoculated variants of both evaluated wheat species. Statistically significant negative correlation coefficients were discovered between content of mycotoxins and many of technological characteristics, for example, DON content and Zeleny sedimentation for common wheat and spelt (−0.60*; −0.66*) and also between DON content and volume weight (−0.63*; −0.95**) for both wheat species. Resulted Mixolab parameters confirmed that Fusarium spp. infection worsens both protein and starch characteristics for both wheat species. However, effect of Fusarium spp. contamination in spelt wheat was generally less pronounced in comparison with common wheat. Despite of visible shifts of Mixolab curves of samples from organic and conventional growing systems, resulted Mixolab characteristics were statistically comparable.

Stimulation sorghum seed leading to enlargement of optimum conditions during germination and emergence

The ways to improve the vitality of sorghum seed after treatment with Lexin and M-Sunagreen were tested in laboratory conditions. These methods of seed stimulation were also tested in field conditions. All experiments were carried out in 2011–2013. Positive results after using the presented formulations for testing of germination were observed not only in laboratory conditions but also in field experiments. Seeds stimulated by Lexin reached statistically higher germination (95%) compared to control (91.5%) with the shortest medium time of germination (3.5 days) versus control seeds (4.3 days). Higher, faster and smoother germination of stimulated seeds resulted in higher average number of plants per m2 (about 2.1 plants/1 m2 in Lexin compared to control seeds) and thereby contributed to higher average yields up to two tons of dry matter per hectare.

The influence of pre-sowing seed treatment by biologically active compounds on soybean seed quality and yield

The aim of the experiment was to improve seed quality of harvested soybean seed by pre-sowing seed treatment with biologically active compounds Lignohumate B (mixture of humic and fulvic acids), Lexin (mixture of humic and fulvic acids enriched by auxins), brassinosteroid (synthetic analogue of natural 24 epibrassinolide) and socalled complete seed treatment (mixture of saturated solution of sucrose, Lexin, Maxim XL 035 FS fungicide of Syngenta and adjuvant on the base of pinolene). Four-year experiments proved positive influence of all treatments to seed parameters (laboratory germination, seed vigour (AA test), field emergence and thousand seed weight).

The possibilities of increasing the production abilities of soya vegetation by seed treatment with biologically active compounds

In three-years experiments soya seeds were treated with biologically active compounds: Lignohumate B (mixture of humic and fulvic acids), Lexin (mixture of humic and fulvic acids enriched by auxins), brassinosteroid (syntetic analogue of natural 24 epibrassinolide) and so-called complete seed treatment (mixture of saturated solution of sucrose, Lexin, fungicide Maxim XL 035FS and adjuvant on the base of pinolene Agrovital). During vegetation following characteristics were observed: field germination, density of vegetation after germination and before har vest, height of plants, height of apical part of the lowest pod from the ground and yield. The results imply that the most effective way of seed treatment is the complete seed treatment, which ensured the yield of 3.29 t of seeds per hectare (average for three years), the second best was the treatment with the compound Lexin, thanks to which the achieved yield was 3.18 t of seeds per hectare.

Forest seed treatment with brassinosteroids to increase their germination under stress conditions.

The effect of different concentrations of brassinosteroids (1:10, 1:100, 1:210) on the germination of sycamore ( Acer pseudoplatanus L.) and ash ( Fraxinus excelsior L.) seeds was investigated in stress conditions. The product Lexin (a mixture of humic acid, fulvic acid and auxin), which also supports seed germination, was selected as a reference treatment. The results show that the most effective is the lowest concentration of brassinosteroids which gave nearly the same effect as the reference product Lexin. The data also suggest the positive effect of pretreatment of sycamore and ash seed in pure water both on germination and germination energy.