Fractionation of seeds is a process commonly used by breeding and seed production companies. Separation of seeds into small, medium and large size fractions depends on a thousand kernel weight and thus on the content of the endosperm of the seeds, which is used in the process of embryo germination. Research showed that large seeds were characterized by a higher field germination capacity and generally seedlings had greater weight compared to those obtained from small seeds. The question then arises whether such fractionation would promote plant yield improvement. Yields of maize (Zea mays L.) plants of cv. 'Boruta' obtained from different size fractions (of different thousand kernel weight) were evaluated in the years 2005-2007. A three-year field experiment showed that yielding of the plants depended on the seed size fraction and decreased with an increase in the size of maize seeds sown. Moreover, in the experiment the germination value of seeds was assessed in cold (10°C) and warm (25°C) tests. The highest germination capacity in both the warm and the cold test (79.0% and 74.0%, respectively) was observed in the small seed size fraction. Germination of large seeds in the cold test was by 6.71% lower (a significant difference) than that of small seeds. The amylolytic activity of three fractions was also examined as indicated by dry and swollen seeds. The results showed the highest activity of amylases in small seeds (7.33 mg maltoze g dry matter-1 min-1) and the lowest in large seeds (4.12 mg maltoze g dry matter-1 min-1).

Many studies have focused on research about impact of time and density of sowing on the agronomic characteristics of different crops. However, the number of studies investigating such a response on the qualitative composition of different types of winter oilseed rape varieties is still limited. The aim of the research was to determine the effect of sowing date and density on yield, protein and oil content and quality of winter oilseed rape varieties: open-pollinated, a typical hybrid of traditional type of growth and a new semi-dwarf hybrid, which biology and yielding have not been thoroughly established. This experiment was conducted applying four sowing dates (August 14, August 25, September 4, September 15), three winter oilseed rape cultivars (PR45D03 -semidwarf hybrid, PR46W31 -hybrid, Californium -open-pollinated) and four sowing rates (30, 40, 50, 60 seeds/m 2 ). Among the compared sowing dates, August 25 proved to be optimal for yielding of the tested winter oilseed rape cultivars. Semi-dwarf variety contained less protein and glucosinolate in seeds, but more oil in comparison to other studied varieties (hybrid and open-pollinated). The yields did not differ significantly within a density of 40, 50, 60 seeds/m 2 , so it is important result, especially for the agricultural practice.

Abstract. Spectral reflectance data can be used for estimation of plant biophysical parameters such as seed yield, related to the use of solar energy. A field experiment was conducted to investigate relationships between canopy reflectance and seed yield of winter oilseed rape sown on four different dates. Ground hyperspectral reflectance measurements were made using a hand-held radiometer and multispectral images were taken with a VIS-NIR camera. The different sowing dates generated a wide range of difference in crop spectral response and seed yields. The strongest relationships (R 2 =0.87) between the yield and spectral data recorded by both sensors occurred at early flowering stages. Later, the presence of flowers caused a decline in the relationship between yield and spectral data especially in the visible (VIS) range. In the full flowering stage the strongest correlation (R 2 =0.72) with the yield showed vegetation indices of the near-infrared (NIR) bands.

The aim of this study was to assess the effects of the agricultural use of sewage sludge in corn for grain, in the year of application and follow up effect after one and two years after its application. The study was conducted on the variety PR39G12 on the field after the 5-year monoculture corn. Sewage sludge was used in accordance with the Directive of Minister of Environment allowing application of 10 t dry mater per ha-1 once every five years. Fertilization with sludge of maize grown for grain did not cause differences in the growth and development of plants, compared to mineral fertilized objects, as well as did not exceed the limit value for heavy metals content in above-ground plant parts. Maize grown using sewage sludge yielded higher than the objects fertilized with mineral, especially in conditions of extreme drought, which occurred in 2006. Beneficial effect of sewage sludge was maintained in the next two years after application and stabilized the grain yield of maize.Keywords: maize, residual effect, sewage sludge, SPAD, yield Abstrakt Celem pracy była ocena efektów rolniczego wykorzystania komunalnych osadów ściekowych w uprawie kukurydzy na ziarno, w roku zastosowania oraz w kolejnych dwóch latach działania następczego. Badania przeprowadzono z wykorzystaniem odmiany PR39G12, na polu po 5-cio letniej monokulturze kukurydzy. Osad ściekowy stosowano zgodnie z ówczesnym rozporządzeniem Ministra Środowiska dopuszczającym aplikację w dawce 10 ton s.m.·ha -1 raz na 5 lat. Nawożenie osadem ściekowym kukurydzy, uprawianej z przeznaczeniem na ziarno, nie spowodowało różnic we wzroście i rozwoju roślin w porównaniu do obiektów nawożonych mineralnie, jak również nie powodowało przekroczenia dopuszczalnych zawartości metali ciężkich w nadziemnych częściach roślin. Kukurydza uprawiana z wykorzystaniem osadów ściekowych plonowała wyżej niż na obiektach nawożonych

Legumes are increasingly important crops in most European Union (EU) countries because of the growing demand for feed protein, and also because they have been shown to improve the characteristics of soil. The main part of the crop rotation is taken up by cereals, but they are connected with undesirable side effects, such as the unilateral utilization of ingredients and the heightened risk of plant diseases, e.g., Fusarium. Simplification of farming methods has become increasingly popular as growers search for cheaper production technologies. However, the effects of long-term simplification in tillage practices on the production and economics of narrow-leafed lupine (NL) cultivation have not been studied. In 2012–2016, we carried out a field experiment in Poland with a one-factorial design with four replications. The aim of the experiment was to evaluate the productivity effect of conventional tillage (CT), reduced tillage (RT) and no-tillage (NT) on NL-winter wheat (WW)-winter triticale (WT)-winter barley (WB), rotation. Our results show that the productivity of this crop rotation was lower under RT and NT systems than under CT. From a practical point of view, the reduction of cultivation in rotation with 75% of cereals caused a decrease in yield in all species, which can result in resign of using the RT and NT in conditions of Albic Luvisols soil, as classified according to the World Reference Base (WRB). The highest incomes were found when the CT system was used with NL. Although income losses exceeded the value of savings in both minimalized soil tillage systems (RT and NT), all tillage systems of NL were profitable.