Volunteer spring triticale (× Triticosecale Wittmack) seed persistence and control

Abstract

Spring triticale is being evaluated as a platform crop for bio-industrial products on the Canadian prairies and may require genetic modification (GM). Seed lost at harvest may persist and result in volunteer GM triticale populations in following crops that could impact co-existence with conventional cereals. Field experiments were conducted from 2006-2010 to assess the persistence of spring triticale in the soil seed bank and evaluate the effect of herbicide timings within four following rotations on volunteer triticale survival and fecundity. Relative to buried seed, triticale on the soil surface persisted longest, although 99% was non-viable after 19 months. Shallow buried seed germinated readily and formed volunteer populations. The combination of pre-seed and crop-specific in-crop herbicides provided the most consistent control, reducing volunteer triticale densities by 72-100%. Competitive subsequent crops, such as glyphosate tolerant canola, in combination with pre-seed and in-crop herbicides, minimize volunteer triticale seed bank replenishment in Alberta.