EJPAU, 2018, Volume 21, Issue 4

The aim of the presented study was to investigate the impact of double phase medium in comparison with single phase medium on the growth and development of axillary and adventitious shoots in the lingonberry in vitro culture. Two-node explants were prepared from shoots collected from mother  in vitro cultures and were placed on single phase and double phase Zimmerman and Boome medium. For double phase medium, 5 ml of liquid medium was added. The composition of the liquid medium was the same as solid one minus agar. The liquid medium was added after positioning the explants horizontally.
   Shoots of axillary origin were used as explants. At the end of each of 3 passages, the number of axillary and adventitious shoots was determined. We demonstrated in presented research that the double phase medium significantly stimulated multiplication and elongation of axillary and adventitious shoots in comparison with single phase medium. Mean number of shoots was about twice higher for double phase medium. Application of double phase medium is a simple method which does not require special equipment. With a minimal increase of costs, it significantly increases the productivity of cultures. Therefore, it may be used successfully in micropropagation of lingonberry plants.

The aim of the study was a comparative analysis of Arab and Hucul hair (winter, summer, mane and tail hairs) with respect to their morphological and histological structure and elemental composition. The research material were horse hair samples collected from adult Arab and Hucul mares maintained in similar conditions. The study included determination of hair length, thickness, breaking force, extension, rupture strength, and histological analysis of scales arrangement and hair cross-section and chemical elements percentage content  obtained using roentgen analysis. The study demonstrated an ability of short hairs molting, which proves to be an adaptation of horses to changing environmental conditions. All kinds of Arab horses hair were thinner and more flexible compared to Hucul hairs. Elemental hair analysis did not demonstrate any differentiation between the examined breeds, however it pointed a potential usefulness of hair examination, e.g. in environment or health status monitoring.

Based on national registers of member countries, European Commission develops the Common Catalogue of Varieties of Agricultural Plant Species [CCA]. The paper regards the following species of pulses from the plant variety catalogues: broad bean, pea, white lupine, blue lupine and yellow lupine, spring and winter vetch, as well as Hungarian vetch. The average number of pulse varieties entered in the common catalogue in the studied 5-year periods was 726 (from 765 in 2000 up to 693 in 2017), and currently it indicates a slight decreasing tendency. France, United Kingdom and Poland prevail in the number of registered pulse varieties in the common catalogue. The average area of commercial sowing of pulses over the analyzed years indicates growing tendencies in the case of broad bean and lupine, decreasing – for vetch, and remaining on the more or less the same level for pea with significant fluctuations, which does not indicate pulses as the growing source of plant protein in EU countries. Production of the qualified seed material was sufficient to change it in the commercial production at least once in every two years, except lupine, where a visible decreasing tendency is observed in supplying farmers with the qualified seed material.

In agriculture and forestry, errors in position and directional information provided by high accuracy global navigation satellite systems (GNSS) lead directly to economic, productivity and environmental losses. The paper focuses on GNSS inaccuracies in the context of kinematic robotic forest harvester operations once a tree has been located. This represents a significant challenge as the geographic location of individual points using GNSS receivers largely requires an unobstructed line of sight from the points to a minimum number of satellites. This is often difficult to achieve in forest environments, as trunks, foliage and humidity can attenuate the GNSS signals besides multipath effects. It is shown by measurements and modeling that the harvesting process trajectories mandate high priority to be given to 3-D location and directional information. Extensive measurements of GNSS inaccuracies on radial grids around a tree position inside forests, some of the very first, have been carried out with the assistance of the Polish Forest Administration Authority. Data acquisition took place in three different forest environments in Poland, characterized by differences in tree heights, species, terrain slope, and rain/humidity levels. Combined with a directional volumetric tree trunk and canopy harvesting model, the data collected allow estimating the yield and productivity direct effects of GNSS errors on precision forestry equipment. It is shown that acceptable yields on trunk wood and logs can be achieved in some types of forest with few robotic harvester moves, in that to some extent the GNSS errors can be compensated by the telescopic arm flexibility of the harvester. The additional use of assistive lidars and other sensors, not considered here, strengthen these conclusions.

A high tolerance to a wide spectrum of environmental factors and excellent taste of its meat explain why the African sharptooth catfish (Clarias gariepinus) is widely used for creating interspecific hybrids with the broadhead catfish (Clarias macrocephalus), a species which is characterized by a high growth rate. However, when the spawning stock on a fish farm is being supplemented with new individuals, there is a serious concern about introducing hybrids instead of purebred individuals. Therefore, it is necessary to develop a quick and reliable method of hybrid identification. In the presented study species diversity was assessed based on PCR and sequence analysis of the internal transcribed spacer 1 (ITS1) and cytochrome oxidase subunit 1 (COI) sequences. Additionally, three restriction enzymes (Fok I, Eco47I and HhaI) were selected and analysed with PCR-RFLP of COI sequences. ITS1 sequence comparisons revealed 0.64% diversity between analysed species and were submitted into GenBank database (KJ136021 and KJ136022). Analysis of COI sequences revealed over 14% variation between two species and based on obtained species-characteristic restriction patterns, a PCR-RFLP test has been developed.

The experiment was conducted in Nowaczyk’s Private Trees and Bushes Nursery in Kobylin in the years 2013–2014. The purpose of the studies was comparison of the effectiveness of grafting of two pines cultivars Pinus densiflora(Japanese red pine)‘Golden Ghost’ and Pinus mugo (Mugo pine) ‘Golden Glow’. Three different rootstocks were used for grafting: Pinus mugo (Mugo pine) subsp. uncinata, Pinus sylvestris (Scots pine) and Pinus nigra (Black pine). Grafting was carried out in three different terms (the middle of February, the end of February and in the middle of March). The highest percentage of grafts success was obtained for two of the studied pine cultivars on Pinus mugo subsp. uncinata rootstock. The dates of grafting did not influence the process of pines grafts success. However the two earlier grafting dates increased the length of shoots. The shortest shoots and the smallest number of buds of 'Golden Glow' cultivar were obtained on Pinus nigrarootstock.

To understand the mechanisms involved in plant responses to metal nanoparticles, the morphological and physiological changes in rapeseed plants (Brassica napus L.) were determined. The sterile seeds were inoculated onto the MS medium (sterilized and unsterilized) containing silver, copper and gold nanoparticles at the concentration of 20 ppm. Silver nanoparticled did not inhibit the germination process as opposed to cooper nanoparticles. The nanoparticles did not affect the roots length. The seedlings grown on the medium supplemented with nanoparticles were significantly shorter in comparison to the control. Nanosilver without autoclave sterilization reduced the plant height. The total chlorophyll, the ratio of chl a / chl b and carotenoid content decreased after the exposure to metal nanoparticles. Additionally, it was found that the nanoparticles of gold increased the activity of catalase, as compared with the control. There is a growing number of research of the biological effects of nanoparticles on higher plants. The application of nanoparticles in in vitro cultures can be very important to facilitate understanding the nanoparticles toxicity for plants.

Tests results of frost susceptibility of clayey gravelly sand obtained from processing of building waste and of fly ashes are presented in the article. Firstly, basic physical properties of both materials were determined and then  frost heave was investigated using a laboratory test permitting to evaluate the frost susceptibility of the soil on the basis of measurement of  frozen sample height increase  The freezing susceptibility of investigated soils  is very distinct, and the research methods  used permitted to evaluate it  quantitative and qualitative way.