Seed row Tolerance of 16-20-0-13 and 12-40-0-6.5S-1Zn in Western Canada


02 Jun 2018

2017 Annual Interpretive Summary

The majority of phosphorus (P)-based fertilizers are either applied directly in the seed furrow (seed row) or side banded close to the seed row, for the growing of small grain cereals, canola, and lentils in the Western Prairie provinces of Canada. A research study assessing the effect of low and elevated application rates of 16-20-0-13S (sulfur) and 12-40-0-6.5S-1Zn (zinc), compared to monoammonium phosphate (MAP), placed in the seed rows of spring wheat, canola, and lentils was continued with a regional research association (Wheatland Conservation Area Inc) based in Swift Current, Saskatchewan. The research was conducted assessing seed row fertilizer effects on both canola and spring wheat during the crop seasons of 2015 and 2016. This research was continued in 2017 to assess the seed row fertilizer effects again on canola, and for 2017 switching to lentils from spring wheat. The change to looking at lentils instead of spring wheat was due to minimal adverse effect observed on the stand of spring wheat in the 2015 and 2016 research. Owing to the increasing amount of lentil acres grown, information on seed row effects is needed.

In 2017, the additional year of research was conducted on a low-P soil 45 km west of Swift Current, SK, near Gull Lake, SK. The canola crop stands were only slightly reduced going from the check treatment (zero P) up to 35 lb P2O5/A for the 16-20-0-13S, and even 40 lb P2O5/A using the 12-40-0-6.5S-1Zn or 11-52-0 fertilizers. There were 10.8 plants/m of row for the check treatment compared to a lowest measurement at 6.3 plants/m for one of the higher rates of P2O5. This lower plant stand did not adversely affect crop yield. For example, the 35 lb P2O5/A rate of 16-20-0-13S yielded 38.4 bu/A compared to a significantly lower yield of canola of 34 bu/A for the check treatment. There was a similar trend for the lentils, as fertilizer rates greater than 20 lb P2O5/A resulted in a slight reduction in crop stand, but yields were not adversely affected. In fact, for both the canola and lentils there was respectively a greater than 3 or 5 bu/A yield response to added P fertilizer for all P rates from 15 to 30 lb P2O5/A, compared to no P applied. This research shows that greater rates of seed row P can be tolerated to at least 30 lb P2O5/A, without significant adverse effects on crop yields.