Hydro-Priming Effects on Seed Germination and Field Performance of Faba Bean in Spring Sowing

Seed priming has been used to advance germination and stand in several crops, but relevant research on faba bean (Vicia faba L.) is scarce. Laboratory and field trials were carried out for two years to study the effect of hydro-priming on faba bean germination and field performance in spring sowing. In laboratory trials, the effects of hydro-priming for 0, 8, 16, 24, 36, and 48 h on final germination percentage, germination speed, Timson's germination index, mean germination time, mean daily germination, synchronization index, and seedling vigor index were studied. All hydro-priming treatments improved germination parameters of faba bean seeds, except for final germination percentage and mean daily germination compared with non-primed seeds. Averaged over priming duration treatments, hydro-priming improved germination speed by 16.2%, germination synchrony by 20.7%, and seedling vigor index by 13.4%. All hydro-priming durations improved germination synchrony, while hydro-priming for 8, 16, and 24 h provided the highest values of germination speed (2.56, 2.58, and 2.37 seeds day(-1), respectively). Hydro-priming for 8 and 16 h provided the lowest values of mean germination time (5.81 and 5.96 days, respectively). In field trials, hydro-priming periods of 0, 8, 16, and 24 h were compared. On average, seed hydro-priming did not affect significantly seedling emergence 14 days after sowing in the first year, but significantly improved seedling emergence by 34.4% in the second year. No significant effect of seed hydro-priming was noted in the number of plants at 28 and 35 days after sowing. Seed priming for 8 h resulted in higher fresh weight at anthesis by 22.3% and 8.6% in the first and the second year, respectively, than the non-primed control. Similarly, seed priming for 8 h provided higher seed yield by 12.0% in the first year and by 5.9% in the second year compared with non-primed control. Overall, seed hydro-priming accelerated faba bean germination and seedling emergence, but the magnitude of the response was associated with the environment and was more evident under limited soil moisture after sowing, whereas the beneficial effect of priming was masked when rainfall followed sowing. Similarly, the beneficial effect of priming on seed yield was more pronounced with limited soil moisture after anthesis.