Perennial lupin establishment and yield when sown at five different rates at Glenmore Station, Lake Tekapo.

Abstract

Abstract The potential for perennial lupins to underpin grass/ legume pastures was the subject of a research programme for merino farmers in areas where more conventional legumes struggle to thrive. A previously uncultivated pasture on an acidic soil, (pH 5.0; Al = 5 mg/kg), and dominated by browntop, sweet vernal and Kentucky bluegrass, was sprayed with herbicide, burnt and top-dressed with 3 t/ha lime on half the area in the autumn prior to direct drilling on 12 Dec 2012. A blue perennial lupin and a multi-coloured (Russell) lupin were sown at 2, 4, 8, 12, 16 and 32 kg/ha and cocksfoot at 2 kg/ha. Yield at four months after sowing had increased with the lupin sowing rate; up to 5.5 t dry matter (DM)/ha at 32 kg seed/ha. The annual yield for the following growth season was greater than 10 t DM/ ha with little response above 8 kg lupin seed/ha. There was a small but inconsistent response to the lime by the Russell lupin. Overall, lupin contributed 79% of annual yield and >90% of the spring yield at sowing rates >8 kg/ha. The sown cocksfoot and resident grasses showed a positive lime response at the lower lupin sowing rates. Key words: Lupinus perennis, L. polyphyllus