Possibilities to improve soil physical properties in garlic cultivation with cover crops as living mulches

[EN] The cultivation system with cover crops as living mulches is growing in importance in the worldwide agriculture as it combines an economical effect with pro-ecological and soil protecting activities. The plant species tested in the research were not frost resistant: buckwheat, millet, white mustard and berseem clover. A control were the plots without cover crops. The intercrops were sown in the first decade of August, in autumn a grown biomass was a living mulch, and after being damaged by frost in spring, the mulch was covering ground surface. Winter garlic bulbs were planted in grown biomass of cover plants, in the first decade of September. In the first decade of November and in the first decade of April, the selected soil parameters were determined in the soil layer of 0¿10 cm: actual soil moisture (%), soil bulk density (Mg · m¿3), total porosity (%) and water stability of soil aggregates (%). The harvest of garlic was conducted in the first decade of July. Cover crops mulches had an influence on soil physical properties. In spring, the soil from plots with cover crops mulching characterized with the highest moisture, higher total porosity and soil aggregates stability as well as lower soil bulk density. In comparison to the control cultivation of winter garlic, without cover crops, the effect of plants used for mulching on marketable yield was not observed. Garlic plants intercropped with the white mustard mulch formed leaves and bulbs of higher weight in comparison to cultivation without cover crops.Research was financed by the Ministry of Science and Higher Education of the Republic of Poland as part of the statutory activities of the Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin.Salata, A.; Moreno-Ramón, H.; Ibañez Asensio, S.; Buczkowska, H.; Nurzynska-Wierdak, R.; Witorozec, A.; Parzymies, M. (2017). Possibilities to improve soil physical properties in garlic cultivation with cover crops as living mulches. Acta Scientiarum Polonorum Hortorum Cultus. 16(6):157-166. https://doi.org/10.24326/asphc.2017.6.14S15716616

Dolichol: A Component of the Cellular Antioxidant Machinery

Dolichol, an end product of the mevalonate pathway, has been proposed a biomarker of aging, but its biological role, not to mention its catabolism, has not been fully understood. UV-B radiation was used to induce oxidative stress in isolated rat hepatocytes by the collagenase method. Effects on dolichol, phospholipids-bound polyunsaturated fatty acids (PL PUFA) and known lipid soluble antioxidants [coenzyme Q (CoQ) and α-tocopherol] were studied. The increase in oxidative stress was detected by a probe sensitive to reactive oxygen species (ROS). Peroxidation of lipids was assessed by measuring the release of thiobarbituric acid reactive substances (TBARS). Dolichol, CoQ and α-tocopherol were assessed by high-pressure liquid chromatography (HPLC), PL PUFA by gas-liquid chromatography (GC). UV-B radiation caused an immediate increase in ROS as well as lipid peroxidation and a simultaneous decrease in the levels of dolichol and lipid soluble antioxidants. Decrease in dolichol paralleled changes in CoQ levels and was smaller than that in α-tocopherol. The addition of mevinolin, a competitive inhibitor of the enzyme 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoAR), magnified the loss of dolichol and was associated with an increase in TBARS production. Changes in PL PUFA were minor. These findings highlight that oxidative stress has very early and similar effects on dolichol and lipid soluble antioxidants. Lower levels of dolichol are associated with enhanced peroxidation of lipids, which suggest that dolichol may have a protective role in the antioxidant machinery of cell membranes and perhaps be a key to understanding some adverse effects of statin therapy

Leaf petioles blanching influence on the yield and chemical composition of cardoon (Cynara cardunculus L.)

The influence of leaf blanching with black polyethylene non-woven (PP) or white and black polypropylene foil (PE) used as soil mulching and blanching of leaves on yield, usefulness and biological value of cardoon leaf petioles were evaluated in the presented work. The effect of blanching duration of petioles (30, 25 and 10 days before leaves’ harvest) on the content of bioactive compounds was also estimated. The aim of the research was to evaluate the total yield of leaves, yield structure, dry weight, content of crude fibre, total sugars, L-ascorbic acid, chlorophyll, phenolic acids in conversion to caffeic acid, total flavonoides and DPPH activity in leaf petioles depending on the method and duration of leaves blanching. The content of apigenin, chlorogenic acid and cynarin in leaf petioles were marked with HPLC. Petioles of non blanched plants showed more dry weight and contained more L-ascorbic acid, chlorphyll, total phenolic acids and flavonoides than the uncovered ones. As a tendency it was observed that together with lengthening the blanching time from 10 to 30 days before harvest, the level of dry weight, crude fibre, total sugars, L-ascorbic acid and chlorophyll decreased. A reverse relationship was observed related to the blanching duration, as extending the time from 10 to 30 days before harvest, the content of total phenolic acids increased from 0.144 to 0.155% of fresh weight, while the content of flavonoides decreased from 0.662 to 0.352% of fresh weight. Lengthening blanching from 10 to 30 days before harvest of leaves decreased the content of apigenin and cynarin in petioles while increased the content of chlorogenic acid. The antioxidant activity DPPH did not depend on the method and duration of blanching. Unusual nutritional and medicinal benefits of cardoon petioles come from its rich and valuable chemical composition

Isoenzyme markers of two hepatic species: Barbilophozia lycopodioides [Wallr.] Loeske, and B. hatcheri [A. Evans] Loeske

Two closely related species of the genus Barbilophozia: B. lycopodioides and B. hatcheri were studied in populations from the Tatra Range (S Poland), where they are frequent and widely distributed. Both species play an important role in plant communities and grow here very often side by side. Typically developed plants are quite easy to distinguish (even in the field), however morphologically intermediate forms, difficult to recognize by using of classical taxonomic methods, sometimes are found. We found enzymatic markers, that allow to recognize the critical forms. Both studied species are different in enzymatic patterns of glutamate oxaloacetate transaminase (GOT) and peroxidases (PX). In GOT four different phenotypes were detected. The first two (GOT 1 and GOT 2) were characteristic for B. hatcheri and next two (GOT 3 and GOT 4) for B. lycopodioides. Peroxidase patterns, that were monomorphic and specific for each species, exhibit different mobility in anodal and cathodal parts of gel. Results of the studies allowed us to draw the conclusion, that PX and GOT are good isoenzymatic markers and they can have practical application for identification of Barbilophozia species