Trinexapac-Ethyl Application Increased Seed Yield of Diploid Red Clover (Trifolium pratense L.)

Trinexapac-Ethyl Application Increased Seed Yield of Diploid Red Clover (Trifolium pratense L.)

Red clover (Trifolium pratense L.) is a perennial legume grown for forage that, when grown with a seed yield focus in New Zealand, averages 260 kg seed/ha (Clifford, 1979). One way to shift the production focus from biomass to seed yield is the use of plant growth regulators (PGRs). Prior work with PGRs in legume seed production has centred on the gibberellin biosynthesis inhibitors paclobutrazol, uniconazol and cycocel that aim to increase the harvest index of a crop by reducing the ratio of vegetative to reproductive biomass. Inhibiting gibberellin synthesis decreases cell division and cell enlargement; reducing the length of internodes and stems (Hedden and Kamiya, 1997). Trinexapac-ethyl (TE), an alternative synthetic gibberellin-biosynthesis inhibitor with low soil persistence was released in New Zealand in 2000.

This work aims to quantify the effect of TE application on the number of inflorescences and seed yield of red clover.