Seed hydropriming in upland rice improves germination and seed vigor and has no effects on crop cycle and grain yield.

Improved seed priming techniques can reduce time between seed sowing and seedling emergence, resulting in rapid and uniform seedlings emergence, high seed vigor, better and uniform stand establishment, better allometric and better yields in many field crops. The objective of this research was to understand the effects of hydropriming on rice seed physiological potential and on crop performance for upland rice systems. Therefore, the laboratory and field trials were carried out. Initially, two seed lots from two upland rice varieties were used to create imbibition curves, required to establish the priming protocols. The priming protocols (zero, as reference, 16 and 22h of priming duration) were applied and their effects on seed physiological potential were evaluated. One seed lot of primed seeds for each variety was used in field trials, carried out in two consecutive growing seasons (2013/14 and 2014/15) in a randomized complete block design, split plot scheme, with six replications. The effects of priming seeds were uniquely associated with their physiological potential, including germination and vigor, which is expected to bring benefits to the faster establishment and uniform stands in the field. However, those benefits did not extend beyond the early stages of crop development and were not observed on flowering and grain yield.