This study aimed at estimating the amount of nitrogen derived by yellow lupine from the atmosphere, mineral fertilizer and soil at different nitrogen fertilization rates and developmental phases of this test plant. Yellow lupine was cultivated in three fertilization variants: without nitrogen fertilization and after application of 30 and 150 kg N·ha^-1. Harvest was performed in flowering and full maturity. In the study ¹⁵N nitrogen isotope was introduced into soil in the form of ammonium sulfate, and the method of isotopic dilution was used. The biomass yield of yellow lupine and the nitrogen content in its individual parts were not significantly dependent on the nitrogen rate. The amount of yellow lupine biomass harvested in full maturity was more than two times larger than in flowering. Nitrogen content in lupine harvested in flowering was higher than in full maturity. Differentiated fertilization with nitrogen, irrespective of the harvest time of lupine, did not have a significant effect on the total amount of taken up nitrogen, which was about two times higher in full maturity than in flowering. The amount of nitrogen derived from biological reduction in the biomass of yellow lupine harvested in flowering was smaller after application of the higher rate of this element, whereas in full maturity this relationship was opposite. The amount of nitrogen derived from the fertilizer increased along with increasing rate. Percentage of nitrogen derived from biological reduction in the biomass of yellow lupine was similar in flowering (53.4 %) and full maturity (51.6 %). Proportion of nitrogen derived from the fertilizer was larger in the 1st time of lupine harvest than in the 2nd time, whereas in the case of nitrogen derived from soil this relationship was opposite. Differentiated fertilization with nitrogen did not significantly affect the percentage of nitrogen derived from biological reduction in yellow lupine. Yellow lupine fertilized with the higher rate of nitrogen contained a higher percentage of this element derived from the fertilizer and lower from soil reserves than after application of the lower rate.

The aim of the research was comparison of the effect of plough tillage and conservation tillage with the use of various catch crops on the yield and grain quality of spring wheat sown in monoculture on rendzina soil. The experiment was set up on rendzina soil with split-plot design in four replications and included plough tillage (A) and conservation tillage, conducted with two methods: with autumn disking of catch crops (B) and with their spring disking (C). At the same time, four methods of regenerating plot in monoculture of spring wheat were conducted in a form of undersown red clover and Dutch ryegrass, as well as catch crops of lacy phacelia and white mustard. The control were plots without catch crops. Plough tillage was favorable for obtaining higher ear density and grain number per ear, which consequently affected increase in the yield of spring wheat grain, compared with conservation tillage. Decrease in the yield of spring wheat grain on plots with conservation tillage, to the highest degree resulted from a decreased ear density. Ear number and grain yield obtained from the plots where stubble catch crops were sown as well as red clover, were significantly higher than on plots after undersown Dutch ryegrass and on the control plots. Better yield of spring wheat on a plot after stubble catch crops and undersown red clover, to a high degree resulted from an increased ear number per unit of area. Tillage systems as well as catch crops did not change significantly 1000 grain weight of spring wheat. Degree of infestation of the spring wheat culm and root with a complex of fungal diseases was not altered by the evaluated tillage systems. Disease index determined for spring wheat on plots after undersown red clover and stubble catch crops as lacy phacelia and white mustard was significantly lower than after undersown Dutch ryegrass and in control without catch crops. The content of total protein and gluten in spring wheat grain as well as sedimentation coefficient did not change under the effect of the applied tillage systems. Application of Dutch ryegrass as a catch crop deteriorated the quality of spring wheat grain.

Lack of water causes non-uniform development of plants during their growing season or even their drying-up. Nitrogen is one of the most important nutrients in the nutrition of higher organisms as well as microbes. Evaluation of the nitrogen nutrition status of plants and determining optimum doses of this element has a significant effect with regard to the economic aspect of production and necessity of protecting agricultural environment against nitrogen pollution. Two-factorial field experiment was carried out in the years 2007-2009 on soil of bonitation class IVa and IVb, and according to agricultural usefulness: complex 4 (very good rye complex) and 5 (good rye complex). The aim of the research was evaluation of the effect of sprinkling irrigation and diversified nitrogen fertilization (0, 80, 160 and 240 kg·ha^-1 N) on chosen elements of the yield structure and on variation of SPAD index in maize leaves (cultivar Clarica, FAO 280). A considerable variation in weather conditions was observed within the years of research. The driest, and at the same time the warmest was 2008, when both in late April as well as in May and June, the amount of rainfall was small. It was observed that the amount of rainfall in May has a significant effect on the maize yield, while sprinkling irrigation applied in June and July reduced the negative effect of drought occurring in late spring. Interaction of the experimental factors indicated that the highest grain yield was obtained after application of 80 kg·ha^-1 N with sprinkling irrigation. However, further increase of nitrogen fertilization dose did not result in any significant increase in the yield of maize grain. The value of SPAD index determined at the stage of flowering (BBCH 67) as well as at the milk stage (BBCH 75) was the highest with nitrogen fertilization of 240 kg·ha^-1. Application of sprinkling irrigation significantly increased values of SPAD readings independently of the level of nitrogen fertilization.

Most flowering species including Brassica genera have genetically controlled ability to out-crossing (gametophytic or sporophytic self-incompatibility – SI). In Brassica, self-incompatibility is sporophytically controlled by a single multiallelic locus, termed the S locus, with more than 100 haplotypes identified so far. From the breeding practice point of view, outcrossing is desired for obtaining acceptable yield level. So, the aim of the present study was to estimate the self-incompatibility and crossability in interspecific hybridization of five chosen Brassica species. The crossed species were: B. napus var. oleifera cv. Californium, B. carinata, B. fruticulosa, B. rapa ssp. pekinensis as well as two varieties of B. oleracea (var. alboglabra and var. gongyloides). The mode of pollination consist of diallel cross-pollination. The pollination was done in the glasshouse of Genetic and Plant Breeding Department of the Poznan University of Life Sciences. The crossability was evaluated on the base of the pollen germination index (PGI) and seed set in all tested cross combinations. The observations of pollen grains germination and pollen tubes penetration were made in pistils of female component of interspecific crosses. They showed unilateral incompatibility in the crosses between B. rapa ssp. pekinensis and B. napus var. oleifera cv. Californium (used as paternal form) as well as bilateral incompatibility in crosses between B. napus and B. oleracea var. alboglabra. Generally, better pollen germination and penetration of pollen tubes were observed in a cross combination where B. napus was used as a maternal parent. Both pre-zygotic and post-zygotic incompatibility barriers were found between analyzed species.

The number of weed species occurring in agricultural crops in Poland ranges from 300 to 400, and in potato cultivation this number ranges from 29 to 55 species. Potato is a plant which is heavily grown over with weeds, since it is cultivated in wide row spaces and is characterized by slow initial growth. The aim of the 3-year study was to estimate the effect of cultivation practices such as limited mineral fertilization, the use of farmyard and straw, catch crop cultivation, as well as the use of a soil fertilizer on the occurrence of weeds in a potato plantation. It was shown that the numbers of weeds determined in three growing seasons before row closure stayed at low level (2-9 plants per m²), and before tuber harvest it was only slightly higher. Among dicotyledonous weed species, the most frequently occurred: white goose-foot (Chenopodium album L.), field violet (Viola arvensis Murr.), smallflower galinsoga (Galinsogaparviflora Cav.) and shepherd’s purse (Capsella bursa-pastoris L Med.), and of monocotiledonous – barnyard grass (Echinochloa crus galli L.) and quack grass (Elymusrepens L.). The lowest weed infestation, particularly with dicotyledonous species, was recorded after the application of straw as organic fertilizer. Smallest number of dicotyledonous weeds occurred when the standard rate of mineral fertilizers was reduced by 50%. Whereas the use of the soil fertilizer UGmax caused increase in the numbers of monocotyledonous weeds before potato row closure and of both monocotyledonous and dicotyledonous before tuber harvest. The smallest weed infestation occurred when straw fertilization was used, mineral fertilization was reduced by 50% and the soil fertilizer was not applied.

The aim of this study was to determine the effect of a catch crop on the content of nutrients in grain of spring barley grown after it, intended for animal feed, using different intensities of chemical plant protection and nitrogen fertilization. Field experiments were carried out at the Research Station at Mochełek on Alfisols, in 2008-2011. The split-plot experimental design was used. The effect of the catch crop (field pea plowed in autumn of the year preceding the barley sowing – factor I) on N, P, K, Ca, Mg and crude fiber content in grains of barley grown with the use of different levels of chemical plant protection (low and high – factor II) was evaluated. Moreover, different rates of nitrogen fertilization were tested (0, 35, 70, 105 and 140 kg·ha^-1 – factor III). The catch crop plowed in the autumn as a green manure significantly increased the nitrogen and phosphorus content in spring barley grain. Intensity of chemical protection of barley had no effect on the content of N, P, K, Ca, Mg and crude fiber in the grain. Increasing the rate of nitrogen in the range from 0 to 140 kg·ha^-1 contributed to increase in concentrations of N, P and K in grain and reduction in the content of Mg. The content of P, K, Ca and crude fiber was negatively correlated with the yield of pea biomass plowed in. Ca concentration in the grain was also negatively correlated with grain yield, whereas magnesium content was positively correlated with both the yield of pea biomass plowed in and grain yield of barley. The study confirmed the importance of the catch crop used as green manure in improving the quality of spring barley grain. Research hypothesis has not been fully confirmed in the impact of this factor on the grain composition of barley grown under low nitrogen fertilization. In treatments without N fertilization the catch crop used as green manure had only an effect on the Ca content in the grain. Barley fertilized with nitrogen at 35 kg·ha^-1 responded significantly to the catch crop used as green manure only by increasing the concentration of potassium and magnesium in the grain.

Abstract: TOP TEN FACTS about Biotech/GM Crops in 2013

Abstract: Global Status of Commercialized Biotech/GM Crops: 2013