Investigation into the contrasting production of eight perennial clover cultivars in the first two years at field sites in in Waikato and Canterbury

The production and pest susceptibility of eight clover cultivars were compared over two years in the pasture at two contrasting sites: a rain-fed Waikato cattle-grazed pasture and an irrigated Canterbury dairy pasture. The cultivars were four white clovers (Trifolium repensL.) (Grasslands Kopu II, Grasslands Mainstay, SF Quest and Weka), two red clovers (T. pratenseL.) (Grasslands Relish, Rubitas), a strawberry clover (T. fragiferum) (Palestine) and a white clover x Caucasian (T. ambiguumM. Bieb.) hybrid (Aberlasting). Grasslands Relish outperformed all other clovers and was associated with the fewest root-damaging nematodes. Both red clovers were less susceptible to insect pests than the white clovers, but Rubitas was vulnerable to root pathogens in Waikato. The poorest performing cultivar was Aberlasting, which was the most susceptible cultivar in all pest and disease measures. The white clovers and strawberry clover performed similarly across most measures. An assay using soils from each site showed that clover seedlings grown in pasteurised Waikato soil were almost ten times larger than those in the non-pasteurised soil whereas pasteurisation made no significant difference with the Canterbury soil. This study demonstrated that root health was a major factor in the contrasting site and cultivar differences in the early years of production.