Niger response to nitrogen and seeding depth in the northern great plains

Abstract

A niger (Guizotia abyssinica (L.f.) Cass.) cultivar has been selected to grow on the Northern Great Plains of North America; however, agronomic management practices in a no-till cropping system regarding seeding depth and nitrogen (N) fertilization have yet to be developed for this region. Two experiments were conducted at Indian Head, SK, Canada from 2011 to 2017 to determine the response of niger to varying N fertilizer rates and seeding depths. Five rates of N (10, 35, 60, 85, and 110 kg N ha-1) and four seeding depths (surface, 0.6, 1.27, and 2.5 cm below soil surface) were applied in separate single factor experiments. Nitrogen fertilizer rate affected niger development. As N rate increased, there was a linear delay in the appearance of visible rows. Plant height and kernel weight were affected by N rate and year, grain yield was affected by year, and there was a linear increase of 18% in grain yield as the N rate increased from 10 to 110 kg N ha-1. Niger plant density was affected by seeding depth, where plant density increased linearly with decreasing seeding depth in 2014, 2015, and 2017, while there was a negative quadratic relationship in 2016. This effect on plant density did not impact grain yield. In conclusion, niger grain yield benefitted from increased levels of N fertilizer and that growers can use a wide range of seeding depths to place niger seed in soil moist enough to support germination and emergence.