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Gegenstand der Untersuchungen sind zwei Dauerfeldversuche, die im Jahr 1984 in Rauischholzhausen (Deutschland) und im Jahr 1996 in Wroc?aw‐Swqjec (Polen) mit vergleichbarer Methode und Zielstellung angelegt wurden. Ausgewertet wurden hier die Zuckerrübenerträge im Mittel der dreijährigen Rotation der Jahre 1997–1999 in Abhängigkeit von organischen und mineralischen Düngungsmaßnahmen. Die erzielten Ergebnisse unterstreichen die Bedeutung der organischen Düngung für die Ertragssicherung im Zuckerrübenanbau. Die untersuchten organischen Dünger Stalldung, Stroh und Biokompost verbesserten die Ertragswirksamkeit mineralischer N‐Gaben.

Die ertragssteigernde Wirkung organischer Dünger war bei fehlender oder niedriger mineralischer N‐Düngung größer als bei hohen N‐Gaben. Auf stark lehmigem Sandboden (Wrozlaw) wurden höhere Ertragseffekte erzielt als auf schwerem Lehmboden (Rauischholzhausen). Die Blatterträge wurden durch die angewendeten Düngungsmaßnahmen stärker beeinflußt als die Rübenerträge. Stroh und Biokompost zeigten die gleichen Ertragseffekte wie Stalldung.  相似文献   
2.
Variable efficiency of androgenesis remains a serious problem in many species of cereals. It is still unclear what makes certain genotypes more amenable to androgenesis than others. This study was undertaken to quantify the previously suspected advantage of winter barley genotypes over spring ones with regard to regeneration efficiency in anther culture. The material consisted of 40 barley hybrids originating from Polish breeding companies. The number of androgenic structures per 100 anthers did not differ significantly between analysed groups (119 vs. 152 non‐significant), but the average regeneration of green plants per 100 anthers was five times higher in winter genotypes (6.4 vs. 1.3). The incidence of albinism was lower for the winter than for the spring materials (70% vs. 90%), while the rate of spontaneous chromosome doubling was similar in both groups (58% vs. 56%). The results strongly support the notion that winter genotypes are more amenable to androgenesis and this may be a consequence of their better adaptation to stress conditions.  相似文献   
3.
In the experiment, yield formation value of vermicompost and manure incorporated into soil were compared in cultivation of sugar beet. It was proved, that vermicompost (10 t/ha) could fully replace manure (30 t/ha) traditionally used for sugar beet. As a result even higher yield of roots, of leaves and biomass using compost were noticed. In case of nitrogen fertilization dose 140 kg/ha seems to be the most suitable.  相似文献   
4.
Doubled haploids (DH) have become a standard tool in breeding and genetic studies of many crops and in most cases androgenesis is the only available route of their production. It has been recently observed that some populations of DH lines obtained via androgenesis contain high proportions of clones. This seriously reduces the efficiency of breeding and may jeopardize genetic studies. This study was designed to determine at which stage of androgenesis these clones are created, using samples set aside during routine production of DH lines in breeding of hexaploid triticale. The fate of each androgenic structure was carefully followed through the entire regeneration process, and all obtained plants were genotyped using DNA markers. Overall, 189 plants were regenerated forming 33 families, each originating from a single original androgenic structure (callus, polyembryos). In ca. 80 % of cases all members of a family were genetically identical. However, in about 20 % of cases the families of regenerants were genetically heterogeneous, showing that not all androgenic structures originate from single microspores. The evidence shown here demonstrates that retention of single plants from each original structure guarantees the production of only unique genotypes but it reduces the total output of plants. If maximum output is desired, multiple regenerants from single callus can be retained but must be genotyped using at least 10 polymorphic markers to identify clones.  相似文献   
5.
Wintergerste in der Fruchtfolge: Zuckerrüben--Sommerweizen--Wintergerste reagierte auf die mineralische N-Düngung stärker als auf die organische Düngung. Der maximale Kornertrag (5,10 t/ha) wurde bei 135 kg N/ha der organischen Düngungsvariante mit Biokompost zur Zuckerrübe erreicht. Winter barley cultivated in crop rotation: sugar beet, spring wheat, winter barley reacted more on differentiated rates of mineral nitrogen than on various organic fertilization. Winter barley yielded highest (5,10 t/ha) upon the effect of 135 kg N/ha after vermicompost application under sugar beet.  相似文献   
6.
The safety assessment of genetically modified (GM) food and feed is performed to identify the possible effects upon animal and human health, also the long-term, multigenerational influence upon functioning of different organs and systems, such as the immune system. In this study C57BL/6J mice were fed for five consecutive generations with pellets containing 20% of conventional triticale grain (control) vs. pellets containing 20% of the transgenic triticale grain resistant to BASTA herbicide (experimental). The F5 experimental animals showed enlarged inguinal and axillary lymph nodes, but not spleens, and increased WBC counts in blood (but within the norm for Mus musculus). Immunophenotyped cell suspensions derived from spleens, inguinal and axillaris lymph nodes and PBMCs from blood showed the significant decrease in the percentage of T cells in spleen and lymph nodes and the B cells in lymph nodes and blood of the F5 experimental mice in comparison to the control F5 mice. Immunoblotting analysis of IL-2, IL-4, IL-10, IL-12, IL- 6, IFN-gamma levels in serum showed significantly increased IL-2 levels and decreased IL-6 levels in the F5-experimental mice sera. No significant changes in the levels of IgE in sera in both mice groups were observed. The obtained results indicate that multigenerational use of feeds for rodents containing the GM-triticale leads to expansion of the B cell compartment in the secondary lymphoid organs, but it is not caused by malignant processes or the allergic response.  相似文献   
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