Evaluation of <i>Sclerotinia sclerotiorum</i> for giant buttercup control in dairy pastures

Abstract

An experiment was established in November 2002 on each of two dairy farms in Golden Bay (East Takaka and Pupu Valley) to evaluate a myceliumonwheat formulation of the fungus Sclerotinia sclerotiorum as a mycoherbicide against giant buttercup (Ranunculus acris) Granules were applied to individual giant buttercup plants or manually broadcast onto infested pasture at 500 kg/ha The mortality of the giant buttercup plants reached 63 at East Takaka compared with 13 at Pupu Valley Survivors were stunted so that the mean size of a treated plant was 27 and 56 of that of untreated plants 100 days after treatment at the East Takaka and Pupu Valley sites respectively These effects remained evident 12 months after application A second experiment confirmed these results