The effects of rice seed dressing with Paenibacillus yonginensis and silicon on crop development on South Korea’s reclaimed tidal land

• DCY84T and SiO2 treatments resulted in best 60 DAS rice seedlings parameters.
• DCY84T and SiO2 treatments increased yield up to 70%.
• DCY84T treatment had the most phosphate [P], potassium [K] and total nitrogen [T-N].
• DCY84T and/or SiO2 treatment highly increased the whole kernel percentage and GABA content of the brown rice.

A field trial to investigate the effects of plant growth promoting bacteria (PGPB) Paenibacillus yonginensis (DCY84T) and/or SiO2 seed coating on rice growth (Oryza sativa L.) was carried out on reclaimed tidal land in Taean County in South Korea. The field test was performed twice between May–October 2014 and May–October 2015, in a randomized complete block (RCB) design with three replications. Treatments consisted of: Mock, DCY84T-treated seeds, SiO2-coated seeds and DCY84T-SiO2-treated seeds and each treatment area covered approximately 300 m2. During the early developmental period of rice seedlings, the SiO2 coating without DCY84T led to the most favorable 30 DAS rice seedling parameters. Moreover, the combination of DCY84T and SiO2 treatments resulted in 2-fold greater fresh and dry weights of 60 DAS rice seedlings compared to Mock seedlings. DCY84T and SiO2, both individually and together, produced a greater grain yield and a greater total yield; specifically, DCY84T and SiO2 treatments yielded a 73% and 70% increase in mass compared to Mock plants, respectively. Rice treated with both DCY84T and SiO2 treatment contained the highest amount of Al, Fe, Ca and Mg, which were 54%, 169%, 42% and 67% higher than the Mock rice, respectively. Remarkably, DCY84T treatment had the most phosphate [P], potassium [K] and total nitrogen [T–N]. DCY84T and/or SiO2 treatment highly increased the whole kernel percentage. Thus, lower its broken kernel percentage to 9.60–24.58%. The protein content of the grain with both treatments was 7.2%, which was greater than that of the Mock grain (6.0%). The content of chlorophyll a, b and carotinoid in the rice leaves which were treated with silica and DCY84 has increased more than the mock without treatment. After harvest, the GABA content of brown rice was increased to 1.9-fold (2014), 1.5 fold (2015) compared to mock grain, respectively. Overall, DCY84T treatment and SiO2 coating can be useful methods for promoting growth of rice under conditions of saline stress. Results from other laboratory trials and greenhouse experiments are also provided.