Effects of Silicon and Zinc Sources on Quantitative and Qualitative Characteristics of Canola at Normal and Late Planting Dates

In order to study the effects of silicon (Si) and zinc (Zn) sources on yield components, seed yield, seed oil content and nutrient concentrations in canola grain at normal and late planting dates, a field experiment was conducted as a split plot-factorial in a randomized complete block design with three replications at Ghaemshahr Agricultural Research Station during the 2017-2018 and 2018-2019 growing seasons. Planting dates as the main plot at two levels (normal planting date, late planting date), silicon fertilizer sources at three levels (control, calcium silicate, nano-Si) and zinc fertilizer sources at three levels (control, zinc sulfate, nano-Zn) were considered as sub-plots. The results showed that all the agronomical and physiological traits studied improved in the normal planting date, while delay in planting date led to a significant reduction in the traits. Application of Si and Zn by both nanoparticles (NPs) and conventional forms significantly increased the yield components, seed yield, seed oil content and nutrient uptake in grain compared to the control plants. There was no significant difference between application of nano-Si and calcium silicate in terms of rapeseed yield and quality. The nano-Zn treated plants showed both higher seed yield and higher nutrient uptake, when compared to zinc sulfate treated plants. The combined application of Si with Zn, especially in the form of nanoparticles resulted in higher seed oil content than the application of Si or Zn alone. In general, the application of Si and Zn in the form of nanoparticles at normal planting date is a promising option to increasing seed yield and improving nutrient uptake in rapeseed.