The effect of foliar application of Calcium Silicate on Salt Stress Tolerance of Two Canola (Brassica napus L.) Varieties

A factorial experiment was conducted in a randomized complete block design with three replications at research fields of Faculty of Agriculture of Tarbiat Modares University, during 2017-2018 growing season. Treatments consisted of three different levels of salinity stress (control), salinity of 5 and 10 dS.m-1) and two levels of calcium silicate (control and foliar application of 8 kg.ha-1) which salinity stress was applied from the beginning of flowering and the calcium silicate was applied at flowering time, and dry weight of the plant, grain yield, yield components, harvest index, oil yield, oil percentage and greenness were evaluated. Foliar application of calcium silicate had positive effects on the all of the traits in both Zarfam and Sarigol cultivars and it increased yield in rapeseed. On the other hand, it was observed that Sarigol had a higher amount in number of pods, number of seeds per pod, 1000 grain weight, harvest index, oil percentage, oil yield and greenness index than the Zarfam. Zarfam had the maximum plant dry weight. In addition, it was observed that salinity stress at 5 and 10 dS.m-1 had negative effects on all studied traits in present study. In general, salinity stress reduced the yield and yield components of rapeseed and the use of calcium silicate reduced the negative effects of salinity stress in both Zarfam and Sarigol cultivars and Sarigol cultivar had more resistance than Zarfam cultivar to salt stress and it used more effectively from calcium silicate.