Herbage and seed yield losses in six varieties of subterranean clover from rust (Uromyces trifolii-repentis)

Abstract

Studies were conducted to determine the herbage and seed yield losses caused by rust (Uromyces trifolii-repentis Liro) in field plots of 6 subterranean clover varieties. By early October (mid spring), rust caused large reductions in herbage production in varieties Green Range (25.9%), Mount Barker (24.8%), Woogenellup (20.3%), Mulwala (18.7%) and Karridale (15.2%). By the beginning of November (late spring), herbage yield losses were greater in Mulwala (50.5%), Green Range (49.4%), Woogenellup (36.9%) and Mount Barker (34.1%). Rust also caused large reductions in seed yield in Green Range (89.4%), Mulwala (84.8%), Karridale (70.2%), Woogenellup (67.2%) and Mount Barker (39.5%). The variety Larisa was highly resistant to rust, with no significant (P>0.05) reduction in herbage or seed yield.