A field experiment was conducted at Rice Research Station, Tonekabon, Iran, to determine the effect of N rate on seed yield, protein and oil content of two canola (Brassica napus L.) cultivars. Two ...canola cultivars ('Hayola-308' and 'RGS- 003') and five N rates (0, 50, 100, 150, and 200 kg ha-1), organized into a randomized complete block design with a factorial treatment arrangement and three blocks, were applied to plot areas. Results showed that N rate effect was significant (P < 0.01) for seed yield, protein content and yield, and oil yield but not for oil content. On the other hand, cultivar had only significant (P < 0.01) effect on seed protein and oil content. Moreover, the interaction between N rate and cultivar was significant at P < 0.01 for seed, protein and oil yield, illustrating that cultivars showed different responses to N rates for these traits. In general, the quadratic equation provided a good description of the relationship between seed, protein and oil yield and nitrogen rate. For 'Hayola-308', seed, protein and oil yield increased significantly as N application rate increased from 0 to 150 kg ha-1, but thereafter remained constant. In contrast, for 'RGS-003', seed, protein and oil yield increased significantly as N application rate increased from 0 to 200 kg ha-1. Therefore, at the highest N application rate (200 kg ha-1), 'RGS-003' produced greater seed, protein and oil yield than 'Hayola-308'. Averaged across N application rate, the seed protein content of RGS-003 was significantly (P < 0.01) higher than that of 'Hayola-308', while the opposite result was observed for seed oil content. This study demonstrated the differential response of two canola cultivars to N rate in terms of seed, protein and oil yield.
At the experimental field of Slovenian Institute of Hop Research and Brewing at Žalec an experiment was conducted in 2006/07 to detect the impact of fertilization by K2SO4 and gypsum on the yield, ...oil content, oil yield, protein content, protein yield and fatty acids composition at two different cultivars of oilseed rape (cultivar Smart and hybrid Toccata). In the conditions of the experiment the source of sulphur did not impact the yield, but a negative impact of spring fertilization by sulphur at cultivar Smart was detected. At hybrid Toccata positive impact of gypsum was detected when it was fertilized at sowing. Oil content was higher at cultivar Smart by 3.32% compared to hybrid Toccata. At cultivar Smart no source of sulphur impacted significantly the yield of oil, while at the conditions of the experiment positive impact of spring applications of sulphur on the yield of oil was detected at hybrid Toccata. Oil yield was higher at cultivar Smart compared to hybrid Toccata. Protein content was not impacted by sulphur fertilization. The share of linoleic acid was higher at hybrid Toccata by 2.2% to 2.4%, the share of oleic acid was higher at cultivar Smart by 2.2% to 3.1%, the shares of other investigated acids did not differ a lot between Smart and Toccata.
Na poskusnem polju Inštituta za hmeljarstvo in pivovarstvo Slovenije v Žalcu smo v sezoni 2006/07 zastavili poskus, v katerem smo preizkusili vpliv gnojenja s K2SO4 in sadro na pridelek, vsebnost olja, pridelek olja, vsebnost beljakovin, pridelek beljakovin in sestavo maščobnih kislin dveh kultivarjev (kultivar Smart in hibrid Toccata) oljne ogrščice. V danih razmerah različne oblike gnojenja z žveplom niso imele značilnega vpliva na pridelek, vendar se pri kultivarju Smart nakazuje negativen učinek spomladanskega gnojenja z gnojili, ki vsebujejo žveplo, pri hibridu Toccata pa pozitiven učinek gnojenja s sadro, če je bila pognojena ob setvi. Vsebnost olja je bila pri kultivarju Smart za 3,32% višja kot pri hibridu Toccata. Pri kultivarju Smart nobena oblika gnojenja z žveplom ni pomembno vplivala na hektarski pridelek olja, pri hibridu Toccata pa se v danih razmerah nakazuje pozitiven učinek spomladanskega gnojenja z žveplom na pridelek olja. Hektarski pridelek olja je pomembno večji pri kultivarju Smart kot pri hibridu Toccata. Na vsebnost beljakovin gnojenje z žveplom ni imelo vpliva. Delež linolne kisline v olju je bil pri hibridu Toccata višji za 2,2% do 2,4%, delež oleinske kisline je bil višji pri kultivarju Smart za 2,2 do 3,1%, deleži drugih maščobnih kislin se pri obeh kultivarjih medsebojno le malo razlikujejo.