Weekly Update – Nysius niger

Nysius niger (Lygaeidae) – Agrologists in Saskatchewan have been querying a greyish-black bug spotted this week in some fields of canola, soybeans and flax.  Photos and descriptions suggest Nysius niger, an ~4mm long lygaeid, is being observed (Fig. 1 and 2). Reports of damage in canola have been matched with observations of these insects active on plants growing in good conditions with no apparent damage. Reports of damage in canola and flax indicate the bugs are feeding on the main stem near the soil surface.

Growers should be cautious – there is no data confirming whether or not Nysius niger is a pest causing consistent levels of economic damage.  Insects can feed on field crop species yet never inflict measurable levels of damage and are therefore not worth managing.  Careful scouting is warranted to assess how these insects are feeding AND if damage is occurring and to what extent.  Also remember our @FieldHeroes who benefit from less insecticide use and instead reserve insecticide use for economically important pests that cause well-researched levels of damage.

Figure 1. Nysius niger adult on the soil surface in a 
canola field in Saskatchewan photographed by J. Bogden.

Figure 2.  Lygaeid nymphs observed in the above 
canola field photographed by J. Bogden.