Selection of sub clover cultivars for New Zealand dryland pastures

Abstract

New Australian-bred cultivars of subterranean (sub) clover with high levels of hardseededness are being promoted in New Zealand based on their superior performance in Australia. These new cultivars may not be suited to cooler New Zealand conditions. The “soft” seeded sub clover ‘Denmark’ dominated the hardseeded cultivar ‘Rosabrook’ in the second year of a dryland grazing experiment near Lincoln (630 mm mean annual rainfall), but in autumn of the third year the ‘Rosabrook’ population recovered to contribute 30% of total sub clover plants. A second field experiment, sown in March 2014 at Lincoln University, compared 10 sub clover cultivars sown with cocksfoot. ‘Antas’, ‘Narrikup’ and ‘Woogenellup’ were most productive at the September 2014 harvest. ‘Antas’, ‘Woogenellup’ and ‘Leura’ had the highest dry matter yields at the November 2014 harvest. In autumn 2015 ‘Narrikup’ re-established most seedlings and ‘Antas’ the least. Until we have better knowledge of the production and persistence of “new” sub clover cultivars under New Zealand conditions, farmers are urged to sow binary mixtures (50:50) of a “new” plus an “older” cultivar.