Trinexapac-ethyl as a strategy for producing seeds of oat (Avena sativa L.) cultivars

ABSTRACT: Trinexapac-ethyl (TE) is used on oat to reduce plant lodging, but little is known about its influence on seed quality. The aim of this study was to evaluate the effects of different application rates of the plant growth regulator TE on the physiological quality and yield of seeds from oat cultivars. The experiment was conducted in the 2019 and 2020 crop seasons in a randomized block design, with four replications, consisting of four rates of TE (0, 50, 100, and 150 g a.i. ha-1) applied when the primary stalk had the first visible node and the second node perceptible node on the oat cultivars URS Altiva and URS Corona. The following variables were evaluated: germination rate, accelerated aging, electrical conductivity, seedling length, seedling dry matter, seedling emergence, and seed yield. Yield response varied, as the URS Altiva cultivar showed no response, while URS Corona showed a positive response only in the 2019 crop season. Both seed germination and seed vigor, evaluated by different tests, were negatively affected as the TE application rates increased. Oat seeds remained within the minimum standards for the seed trade up to the application rate of 100 g a.i. ha-1. The application of TE reduces the germination and vigor of oat seeds.