Rice seed vigor can affect speed of germination, field emergence and crop yield. These agronomic performance characteristics are essential for sustainable production of rainfed, dry direct-seeding rice. Seed priming may enhance rice seed vigor and agronomic performance for rainfed production. The objective of this study was to evaluate the effect of GA3 and wood vinegar seed priming on seed vigor, seedling performance, and grain yield in farmer’s fields. The experimental design was a splitsplit plot with 4 replications and planted in Thailand between April to December, 2013 and 2014. Two rice cultivars (KDML 105 and RD6) were main-plots, 2 planting methods (broadcast and row) were sub-plots and 3 seed priming treatments (GA3, wood vinegar and untreated control) were subsub- plots. Seed priming enhanced speed of germination and final germination percentage under laboratory and field condition. However, field agronomic performance was strongly influenced by year of production. Wood vinegar primed seeds had greater shoot growth and plant population, while GA3 primed seeds had faster speed of seed germination and greater germination percentage. Total weed biomass was different between rice cultivars and planting methods. At 20 and 40 days after sowing (DAS), weed biomass was dependent on planting method and cultivar. Seed priming significantly reduced weed biomass at 140 DAS in 2013, but not in 2014. Yield-related agronomic performance characteristics of tillers plant-1 and yield in ton ha-1 were significantly higher for primed seed in 2013. Seed priming with wood vinegar is a good, sustainable alternative to improve seedling emergence and increase yield of dry direct-seeding rice. However, the response depends on optimal soil moisture availability during flowering and seed formation.
Available at: http://works.bepress.com/asusana-goggi/24/