Die Bodenkultur - Journal for Land Management, Food and Environment
M. Ijaz and B. Honermeier:
Effect of different fungicides on seed yield and grain quality of rapeseed (Brassica napus L.) under two levels of nitrogen fertilization
Field experiments with winter rapeseed including two study factors (fungicides/growth regulator and nitrogen) were carried out in 2008/09 and 2009/10 at two experimental stations. Triazole and strobilurin fungicides and trinexapac as growth regulator were applied in 14 combinations at three different growth stages of winter rapeseed. Results revealed that autumn-applied treatments did not have any effect on plant height in comparison with control. Contrarily, spring applied treatments alone as well as in combination significantly reduced plant height. Leaf area index after flowering was improved in those treatments which included strobilurin as second application at BBCH 65. Seed yield and morphological parameters were not affected significantly by application of fungicides in any experiment. Significant interaction between fungicides and nitrogen was found for oil content in 3 of 4 experiments. Changes of peroxide value and free fatty acid concentration were caused by fungicidal treatments as well as by environmental conditions. Fungicides changed the composition of fatty acids significantly in both growing years. Higher level of nitrogen enhanced seed yield, protein content and glucosinolates, while it decreased oil content in all experiments.
Key words: Triazole, strobilurin, nitrogen, seed yield, oil content, fatty acid.