In the years 1998-00 two field and laboratory studies on the fertilization value of straw of wheat and winter rape were carried out in the experimental station in Pawlowice near Wroclaw (Poland). Winter rape cultivar Silvia was fertilized with straw of winter wheat cultivar Kobra in the first series. Winter wheat cultivar Kobra was fertilized with straw of winter rape cultivar Silvia in the second series. Examined agrotechnical factors have not exerted distinct influence on lenght of growth stage of rape and winter wheat. Winter rape cultivated after ploughing straw of winter wheat, comparing with without straw, were developing slower in autumn, had 12 percent more siliques per plant and had 10 percent more seeds yield and crude fat. Winter wheat cultivated after ploughing straw of winter rape comparing with without straw, had about 5 percent less amount of grains in the ear and 4.3 percent less amount of grains yield

Use of herbicides is very important for reducing looses of the yield in wheat production in Latvia. The aim of experiments was to investigate effect of herbicides Lintur, Secator, Ariane, Duplosan Super on yield and quality of spring and winter wheat. Herbicide efficiency was studied on spring wheat variety Dragon and winter wheat variety 'Kontrast'. The yield, structure of yield, weediness and quality indicators - content of gluten, content of proteins and Zeleny index were determined. The results showed significant increasing of yield and grain quality numbers of spring wheat in all variants of herbicide use, except variant with herbicide Lintur. The most important weed species reducing grain quality indicators were: Galium aparine L., Lamium purpureum L., Veronica arvensis L., Convulvulus arvensis L., Matricalia perforata Merat. In the winter wheat trials situation was different. Significant yield increasing was in all variants of herbicide use to compare with untreated. The grain quality indicators were not essentially increased in variants with herbicides Lintur, Ariane and Duplosan Super. Only in the variant with herbicide Secator use was significant increasing of these indicators. The reduction of weediness caused by herbicide use, has bigger increasing of quality indicators of spring wheat than of winter wheat. Reasons for these are different plant development and natural competitiveness of winter wheat

In Research - breeding station Viglas - Pstrusa were researched 19 varieties of winter wheat at two different levels of fertilization since 1997. The aim was find out crop tested varieties, protein contents and wet gluten. The valuation of economy cultivation at different levels of fertilization was made too

Non-Peer Reviewed | Successful production of winter wheat on most of the Canadian prairies requires direct seeding into standing stubble of the previous crop. Crop rotation is often seen as a limiting factor to the expansion of winter wheat acres in this system as the previous crop needs to be harvested early enough to allow winter wheat to be seeded by late August or early September, depending on location. This project was initiated with the objective of developing a practical tool to assist farmers in selecting seeding dates for several spring crop species so that winter wheat can be planted during the optimum period for fall establishment. Degree-days, or heat unit requirements, to produce a physiologically mature crop were determined for Polish canola, barley, oat, mustard, Argentine canola, hard red spring wheat, and flax. Daily climate data was then used to determine the probability of the crops reaching physiological maturity by specific dates in the fall when they were sown between May 1 and June 9 at selected locations in western Canada. Future plans are to expand the number of sites to include over 9,000 station years of weather data so that risk maps and fact sheets with tables can be produced to assist farmers in planning rotations for winter wheat. While the initial objective of this project has focused on winter wheat production, there are a large number of additional uses for this type of management tool.

The given research on the influence of herbicides on the yield and quality of winter and spring wheat was carried out in the company Dobele Agra during the period of two years. Four herbicides - Lintur, Ariane, Duplosan Super and Secator - were tested on winter and spring wheat in field trials. Their effect was compared. The yield and the quality of crop, yield structure as well as weed infestation were determined. Grain quality indices (gluten content, protein content, zeleny index) were analysed in the laboratory by means of infrared wave method and the Infratec 1275 analyser. The obtained results show significant increase of the yield and grain quality values of spring wheat in all the cases of herbicide application except for the treatment with Lintur. In the trials with winter wheat all the above mentioned herbicides increased crop yields significantly, though the increase of grain quality was observed in the case of the treatment with secator. The reduction of weed infestation had greater influence on the quality of spring wheat compared to that of winter wheat.

The studies were carried out in the Agricultural Experimental Station in Pawlowice near Wroclaw (Poland) in 1998-00. Soil samples were taken only from fields without straw ploughing and without Ca and N fertilization classified as 0 Ca and 0 N. The species composition and dominance structure of Collembola from oil seed rape and winter wheat fields were analysed. 18 species of Collembola were identified in oil seed rape and 17 on winter wheat fields. Jaccard's index was extremely high (94.2 percent). This means that the fauna in both fields was very similar. The percentages of dominants and subdominants in the global spectrum of springtails of soil seed rape and winter wheat fields were almost identical. However, the different species were dominats on oil seed rape (Isotomiella minor and Isotoma viridis) and on winter wheat fields (Mesaphorura krausbaueri and Isotoma notabilis)

When contracts for the Conservation Reserve Program (CRP) expire, highly erodible land that had a long-term vegetative cover composed of grasses or grass-legume mixtures may be converted back to cropland. Considering that some of the same leaf spot pathogens found on grasses can cause diseases on wheat, the management practices used to convert these lands were evaluated for their effect on winter wheat leaf spot diseases. In a 3-year spring wheat-winter wheat-pea crop rotation, the major leaf spot diseases on winter wheat were tan spot and Stagonospora nodorum blotch. Removal of hay or leaving hay in the plots when converting grassland to cropland had no significant effect on leaf spot diseases, indicating that the residue from the grass-alfalfa crop did not influence leaf spot diseases on winter wheat. Tillage treatments did not influence the amount of disease in 1996, but with higher precipitation levels in 1999, higher disease severities were associated with the no tillage treatment. Higher levels of crop residue associated with the no tillage treatment could potentially carry over plant pathogens from one crop to the next. The severity of leaf spot diseases was consistently lower when nitrogen was applied, indicating the importance of nitrogen application when converting grassland to cropland.

The objectives of the paper were to determine the influence of retardant, herbicide and nitrogen on growth dynamics and the development of vegetation stages in winter wheat. The field experiments were carried out during 1998 to 2000 in Research and Training Farm 'Peterlauki'. The growth dynamics was registered by aucsinographs. The data show that the growth of winter wheat was seriously hindered even two weeks after the treatment with agro-chemicals. The growth of winter wheat in length stopped in midflowering stage. Growth rhytm change is observed in winter wheat treated with agrochemicals. There are not observed any changes in initial plant growth, but beginning with the fifth day after treatment, plants are in stress conditions. Up to fourteen days, the intensity of plant day-night growth in length was changed in all the treatments

The field experiments with winter wheat (var. Almari) were performed at the Experiment Station Tomaszkowo near Olsztyn during 1994-96. The wheat was grown after field bean on proper brown, heavy wheat soil in two-factorial experiment, carried out in spilt-plot design in 4 repetitions. The Granstar 75 DF herbicide applied in the doses of 18 and 24 g per ha as well as urea foliar application in concentration of 18 and 24 percent had considerably positive influence on winter wheat yield

The efficacy of soil tillage and sowing technologies on the yield of winter wheat were studied on sod podzolic loam soils in the LUA Research and Study Farm (RSF) "Vecauce" during 1998 to 2000. Conventional early ploughing, late ploughing with soil pacomat and sowing without soil reversing were used as comparison variants of soil tillage for winter wheat. The use of soil pacomat and local mineral fertilizing increased the yield of winter wheat in the research conditions. Direct sowing and conservation soil tillage gave a decrease of cost per ha and provide the same level of yield achieved with classic soil tillage and sowing technologies