A COMPARISON OF BROADCAST AND DRILL METHODS FOR NO-TILL SEEDING WINTER-WHEAT

No-till seeding into standing stubble of a previous crop is required to provide a trap for snow that protects overwintering wheat from low temperature extremes experienced in most of western Canada. In this production system, the optimum winter wheat seeding date often conflicts with spring crop harvest. Broadcast (aerial) seeding into an immature, standing spring crop would provide an opportunity to eliminate this conflict for limited resources during harvest. The objectives of this study were to determine the effect of broadcast seeding date and rate on winter wheat establishment, development, and productivity and to compare broadcast and conventional no-till winter wheat seeding methods in east-central Saskatchewan. Eight field trials were conducted over 2 yr. Seedlings from broadcast seeding had more prostrate growth habit and lower establishment levels than those produced with conventional seeding methods. Unlike conventional drill seeding, pre-seeding soil moisture was not an important factor in broadcast seed germination. When broadcast seeding rate was increased from 67 to 202 kg ha-1 there were increases of 167, 66, and 91 % in plants m-2, spikes m-2 and grain yield, respectively. Highest broadcast seed yields were obtained with a seeding date of 15 August at seeding rates ranging from 164 to 202 kg ha-1. Maximum grain yields were higher for conventional drill than for broadcast seeding methods. A heavy reliance on post-seeding rainfall, high seeding rates and a greater risk of failure more than offset the advantages of speed, better opportunity for timely seeding and improved labor distribution with broadcast compared to drill seeding methods.