Emergence and seedling growth from osmotically primed or pregerminated seeds of asparagus (<i>Asparagus officinalis</i>L.)

Abstract

SummaryThe optimum priming treatment for seeds of ‘UC 157’ asparagus was one week in –0.6 MPa polyethylene glycol 8000 at 20°C following three days in water at 20°C. This treatment advanced the time to 50% germination by 5.3 days but did not improve the synchrony or percentage of germination relative to those of untreated seeds. The emergence and plant growth responses from primed or water-soaked seeds that were sown dry or fluid-drilled were compared with those from either 100% germinated seeds that were fluid-drilled or untreated seeds. The relative responses to these treatments were similar under both glasshouse and field conditions. Seedling emergence was more rapid from primed seeds than from water-soaked ones but increased drying of both before planting led to slower emergence. Whilst the most rapid emergence occurred with primed seeds that were fluid-drilled (without drying), emergence was even earlier when 100% germinated seeds were fluid-drilled. Crown fresh weights of plants from primed or germinated seeds that had been fluid-drilled were 40% and 48% greater, respectively, than those from untreated seeds 15 weeks after two sowing dates.