Effect of triazole and strobilurin fungicides on seed yield formation and grain quality of winter rapeseed (Brassica napus L.)

Field experiments were conducted over two growing seasons at two sites to study the effects of various combinations of nine triazole and strobilurin fungicides and one growth regulator applied at two growth stages on the seed yield and oil quality of winter rapeseed. Plant height and green area index were both significantly influenced by the fungicide/growth regulator regime. An optimized fungicide/growth regulator regime can limit losses in seed yield and oil quality caused by lodging. Treatments applied first at the green floral bud stage and then at the pod development stage increased the crop's photosynthetic ability, delayed its senescence, and improved aspects of plant architecture associated with seed yield. Triazole/strobilurin combinations were effective in raising seed yield. Seed oil accumulation was affected by the treatments in all experiments. Significant effects of some fungicides on either the free fatty acid content or the peroxide value in the seed oil were noted, but they had no prominent effect on the relative content of saturated and unsaturated fatty acids of the oil.

► We apply triazole and strobilurin fungicides alone and in combination on rapeseed.
► We examine growth, yield and quality parameters of rapeseed.
► Combined applications of these fungicides improve LAI and seed yield as compared to alone application.
► Inclusion of growth regulator (Moddus) in these fungicides enhances oil content of rapeseed.
► These fungicides have significant effect on the concentration of fatty acids.