Effect of Paclobutrazol on Seed Yield in the Subtropical Grass Digitaria eriantha

Lodging of Digitaria erlantha can reduce seed yield of well-fertilised seed crops. This experiment was designed to assess the effect of the growth retardant paclobutrazol on seed production and its components in a spring crop of D. erialllha cv. Premier. Paclobutrazol decreased lodging, reduced tiller height and weight and tended to increase seed set, seed weight and seeds per panicle. However, it also tended to reduce panicle density. Treatment with 0.75 kg ai/ha applied at initial panicle emergence was optimal, increasing pure seed yield from 305 to 462 kg/ha. Paclobutrazol has potential for increasing seed yield in D. erantlta through preventing lodging when high levels of nitrogen fertiliser are applied.