The article presents the effect of three sowing dates on the growth, development and yielding of four soybean cultivars of different earliness and under different temperature and precipitation conditions across the years. The seed yield from early sowing significantly correlated with the total precipitation in June and July, and at later dates, also with the total precipitation in August. The significantly highest soybean yields were collected from the sowing at a turn of April and May, and the highest seed and protein yield, as well as protein content in seed, were recorded for the mid-early Merlin cultivar. Neither the number and the seed weight per pod nor the 1 000-seed weight significantly depended on the sowing date. Over years, a significant, almost linear decrease in the plant height and the first pod setting height, the weight of nodules, the protein yield and the LAI (leaf area index) value was observed. High significant correlations were found between the seed yield and the plant height and the first pod setting height, as well as between the seed number and the seed weight per pod and the 1 000-seed weight as well as between the plant height and the first pod setting height.

Two-way field experiment was carried out in a split-plot design in 4 growing seasons at the Experimental Station of the Bydgoszcz University of Science and Technology in Mochełek (Poland). The forecrops for winter triticale cv. Tulus were lupins: yellow, blue and white, field pea and spring barley. Nitrogen (N) fertilization in triticale after harvesting forecrops was: 0-60-120-180 kg N per ha. Average long-term yields of grain and protein in triticale after leguminous forecrops were statistically similar, by 0.84 t/ha and 86 kg/ha higher than after spring barley. On plots without mineral N fertilization, by over 1.5 t/ha more grain was obtained after leguminous forecrops, and by 142 kg/ha more protein than on the plot after spring barley. However, the rate of 180 kg N/ha guaranteed obtaining a significantly highest mean protein yield in triticale. The applied mineral N fertilization at rates from 60 to 180 kg N/ha did not significantly vary the average yield of winter triticale. Mineral nitrogen (N min ) content in the layer 0-60 cm after harvesting the leguminous forecrop without mineral N fertilization was by 25.5% higher than after harvesting spring barley fertilized with a rate of 60 kg N per ha.

The paper presents results of 3-year field studies carried out in a split-block design in four replications in the years 2012-2014 at the Agricultural Experiment Station in Mochełek (Poland). The effect of intensification of cultivation technologies on the yield of morphologically diversified cultivars of white (Lupinus albus), yellow (L. luteus) and narrow-leafed lupin (L. angustifolius) was examined. Traditional cultivars of white and yellow lupin gave significantly higher yields than the self-completing ones, as opposed to narrow-leafed lupin in which the self-completing cultivar had higher yields. Increasing expenses on industrial production means caused an increase in the yield of all the studied species. Seed yield of white and narrow-leafed lupin was significantly the highest in high-input technology, while that of yellow lupin in high-and medium-input technology. In all lupin species, insignificant diversification was observed in the number of pods per plant in medium-and high-input technologies as well as in low-and medium-input technologies. A significant increase in the seed yield along with an increasing intensity of the cultivation of traditional and self-completing cultivars of white and yellow lupin, as well as self-completing cultivars of narrow-leafed lupin, resulted mainly from developing a higher number of pods.

A growing interest in soybean cultivation in Poland has been observed in the recent years, however it faces a lot of difficulties resulting from a poorly understood effectiveness of plant nitrogen fertilization and from the introduction of Bradyrhizobium japonicum to the environment. The aim of the study was to evaluate the consistency of response of two soybean cultivars to three different rates of mineral N fertilization and two seed inoculation treatments with B. japonicum in field conditions over four years regardless of previous B. japonicum presence in the soil. A highly-diversified-over-years rainfall and temperature in the growing season do not allow for a definite statement of the differences resulting from seed inoculation and mineral N fertilization applied separately or jointly in soybean. A high sensitivity of the nodulation process to rainfall deficits was noted, which resulted in a decreased amount of B. japonicum DNA measured in qPCR and dry matter of nodules. ‘Annushka’ demonstrated a higher yield of seeds and protein, higher plants and the 1st pod setting. ‘Aldana’, due to a significant decrease in plant density, produced a higher number of pods, seeds per pod and the 1000 seed weight per plant. Both cultivars responded with an increase in the seed yield after seed inoculation with HiStick, also with an application of 30 and 60 kg N, as well as with Nitragina with 60 kg N.