Camelina Yield Response to Different Plant Populations under Dryland Conditions

Poor stands of camelina [Camelina sativa (L.) Crantz., Brassicaceae] usually result from poor seedbed conditions or unfavorable environmental conditions. A 2-yr field study was conducted under dryland conditions near Huntley, MT to evaluate the effects of stand reduction at rosette and bolting growth stages on camelina grain yield and quality and to determine if camelina has compensatory ability for grain yield aft er a stand loss. Camelina exhibited tremendous compensatory ability to maintain grain yield across a wide range of plant populations. Stand reduction up to 50% either at rosette or at bolting stage had no effect on grain yield over 2 yr. A 90% stand reduction reduced grain yield by 50% when it occurred at bolting, but only 19% when stand was reduced at rosette stage. In general, stand reduction treatments increased seed protein content while reducing seed oil content. This change in protein and oil content was consistent and greater for bolting stage stand reduction treatments. Stand reduction resulted in reduced plant height and delayed plant maturity, however the response was not consistent over years and stand reduction treatments. Stand reduction at rosette stage had little effect on camelina maturity (1-2 d), while stand reduction at bolting stage delayed maturity up to 6 d. This implies that stand loss due to hail damage or other environmental conditions at bolting or later growth stages may cause delayed and uneven maturity which may result in harvesting problems and/or increased shattering losses.