The objective of this study was to determine the effect of the biostimulant Kelpak and different nitrogen rates on cellulose, hemicellulose and lignin contents as well as non-structural carbohydrates in orchard grass and Braun’s festulolium. The experiment was a split-plot arrangement with three replicates. It was set up at the experimental facility of the University of Natural Sciences and Humanities, Siedlce, in late April 2009. The following factors were examined: biostimulant with the trade name Kelpak SL applied at 2 dm3 ha−1 and a control—no biostimulant; nitrogen application rates 50 and 150 kg ha−1 and a control (0 kg ha−1); pure stands of grass species grown in monoculture—orchard grass (Dactylis glomerata), cv. Amila,—Braun’s festulolium (Festulolium braunii), cv. Felopa. Kelpak significantly increased non-structural carbohydrates, and increasing nitrogen rates reduced the concentration of these components in plants. Increasing nitrogen rates significantly decreased cellulose, hemicellulose, lignin and non-structural carbohydrate contents. Compared with orchard grass, Braun’s festulolium proved to be of a higher nutritional value due to lower cellulose, hemicellulose and lignin contents and more non-structural carbohydrates. The aforementioned contents in the grasses differed significantly depending on the cut. Most cellulose and non-structural carbohydrates were determined in second-cut grass whereas most hemicellulose and lignin in second-cut grass.

The effect of traffic on the content of lead and cadmium in grass morphological parts—leaves, shoots, and inflorescences—was studied. The samples were taken on a part of the European route E30 (Siedlce by road). The following plants were tested: Dactylis glomerata, Arrhenatherum elatius, and Alopecurus pratensis. During the flowering of grasses, the plant material was collected at distances of 1, 5, 10, and 15 m from the edge of the road, on the strip of road with a length of 9 km. In the collected plant parts, the content of lead and cadmium using the atomic absorption spectroscopy (AAS) method was determined. The effect of distance from the road on the content of lead and cadmium was evaluated using regression equations. Average lead content in the above parts of tested grass species was 3.56, while cadmium 0.307 mg kg−1 dry matter (DM). Lead content in plants of Alopecurus pratensis (average 4.11 mg kg−1 DM) was significantly higher than in other grasses. The lowest cadmium content, significantly different from the other species, was found in plants of Arrhenatherum elatius (0.251 mg kg−1 DM). Distance of sampling sites from the roadway significantly affects the differences in the content of cadmium and lead in plants. Analyzed aboveground plant organs of studied grasses were significantly different in contents of lead and cadmium. There were species differences in the proportions of cadmium concentration in various organs of plants. The obtained results indicate the possibility of species composition selection of grassland sward in areas with a higher risk of heavy metals associated with dust sedimentation.

In 2011 a study was carried out analyzing the effects of road traffic on bioaccumulation of zinc and copper in selected species of dicotyledonous plants growing on adjacent grasslands. To do the research the plants were sampled from the 9-km-long Siedlce bypass, a part of the international route E-30. They were collected during the flowering stage, at following distances from the road: 1, 5, 10, 15 m. The content of zinc and copper was determined with the AAS method, with dry mineralisation done before. The highest concentration of the elements, regardless of the distance from the road, was found in Taraxacum spec. Among the tested plants, the lowest zinc content was in Vicia cracca, and the lowest copper content in Rumex acetosa. The limit for copper content was exceeded in Taraxacum spec. and, slightly, in Achillea millefolium growing at the roadside, closest to the roadway.

The objective of the present work was to determine the effect of various biostimulants on sand lucerne yielding and content of chlorophyll, proteins, and simple sugars against the background of nitrogen fertilisation regime. A field experiment was arranged as a randomized subblock design (splitplot) with three replicates at the Siedlce Experimental Unit of the University of Natural Sciences and Humanities in Poland in the second decade of August 2013). The following factors were examined: type of biostimulant: Algex, Tytanit, Asahi SL and a control (no biostimulant addition); nitrogen application rate: 0 (control) and 30 kg ha -1 . Statistical analysis demonstrated that the biostimulants applied significantly increased plant biomass yields but the effect was more beneficial in plots to where no nitrogen had been applied. Chlorophyll content in lucerne leaves and monosaccharide content were significantly higher following an application of all the biostimulants. Their effect on the sand lucerne content of protein compounds varied. An application of Tytanit and Algex contributed to an increase in protein compounds in test plants but, for Algex, the differences were statistically insignificant. By contrast, an application of Asahi SL was followed by a significant decline in the concentration of protein compounds in lucerne plants. Significantly higher average dry matter yields, a higher average chlorophyll content and a higher average concentration of protein compounds were noted in plots fertilised with nitrogen compared with non-fertilised units. However, nitrogen fertilisation regime significantly reduced the sand lucerne content of simple sugars.

An experiment was conducted to determine the effect of an application of biostimulants, against the background of varied nitrogen regime, on the share of neutral detergent fraction (NDF), acid detergent fraction (ADF), and acid detergent lignin (ADL) in the crude fiber fraction of Italian ryegrass as well as its digestibility. A field experiment was arranged as a randomized subblock design (split-plot) with three replicates at the Siedlce Experimental Unit of the University of Natural Sciences and Humanities in Poland in 2013. The following factors were examined: type of biostimulant: Algex, Tytanit, Asahi SL and a control; nitrogen application rate: 0 (control); 120 and 180 kg·ha−1. There were confirmed positive effects resulting from an application of biostimulants in Italian ryegrass cultivation. There was confirmed the assumed hypothesis that an application of both natural and synthetic biostimulants will make it possible to improve the feeding value of grasses by reducing the fiber fraction. Particular attention should be paid to the biostimulant Algex whose application in Italian ryegrass cultivation produced the most beneficial response in terms of the share of NDF, ADF, and ADL fractions, which resulted in the greatest increase in the plant dry matter digestibility. Increasing nitrogen rates significantly reduced the quantity of analyzed fiber fractions, and increased grass digestibility.