Regional crown rot management – Bithramere 2014

Abstract

Key findings • Heavy crown rot infection in inoculated plots led to yield loss ranging from 14% (Sunguard [PBR]) up to 47% (EGA Gregory [PBR]) even in this relatively high yielding site (average yield of 4.67 t/ha) in 2014. • Variety choice had a large impact on yield in the presence of high levels of crown rot infection with all but two entries being between 0.65 t/ha (Sunmate [PBR]) to 1.71 t/ha (LRPB Spitfire [PBR]) higher yielding than EGA Gregory [PBR]. • Sunguard [PBR] was also the only entry to have screening levels <5% in the presence of high crown rot infection at this site in 2014 with LRPB Spitfire [PBR] just exceeding the threshold. • In‑crop fungicide application at GS30, provide a modest yield benefit of between 0.23 to 0.34 t/ha when targeted at the base EGA Gregory [PBR] plants infected with crown rot.