Effect of foliar application of nano iron and manganese chelated on yield and yield component of canola (Brassica napus L.) under water deficit stress at different plant growth stages

In order to study the effect of nano- iron and manganese fertilizer, a field experiment was conducted at 2013-2014 growing season at the Research Farm in Faculty of Agriculture, Tarbiat Modarres University, Tehran, Iran. Experiment was conducted as a randomized complete block design arrangement in split plot with three replications. Three irrigation regimes (without water deficit stress, water deficit stress at vegetative stage and water deficit stress at reproductive stage) were randomized to the main plots and combinations of foliar nano-iron and nano-manganese application as were randomized to the sub plots. Statistical analysis showed that irrigation and spraying regimes and their interactions had significant effect on most of the measured traits. Water deficit stress significantly reduced yield and yield components of RGS canola variety. The most reduction was observed in plants under water deficit condition at reproductive stage. Use of micronutrients increased canola grain yield. The maximum grain yield was observed in plants that treated with iron sulfate 1 per thousand + manganese sulfate 1.5 per thousand. In general, low concentration levels of iron and manganese foliar application was more effective on plants for reduction harmful effect of water deficit levels than high micronutrient concentrations.