Biofertilizer with Bacillus pumilus TUAT1 Spores Improves Growth, Productivity, and Lodging Resistance in Forage Rice

Bacillus pumilus strain TUAT1 is a plant growth-promoting bacterium (PGPB) applied as a biofertilizer, containing its spores, for rice. In this study, we analyzed the short-term effects of biofertilization on plant growth in the nursery and long-term effects on plant vegetative growth, yield, and lodging resistance in paddy fields using animal feed rice ('Fukuhibiki' and line LTAT-29 which was recently officially registered as a cultivar 'Monster Nokodai 1') and fodder rice (line TAT-26). The effects of the biofertilization were analyzed under two nitrogen treatments and at two transplanting distances in the field. The application of 10(7) colony forming units (CFU) mL(-1) bacterial spore solution to seeds on plant box significantly improved the initial growth of rice. The biofertilizer treatment with this strain at 10(7 )CFU g(-1) onto seeds in nursery boxes increased the nitrogen uptake at the early growth of rice in the field, resulting in higher growth at the late vegetative growth stage (e.g., tiller number and plant height). Furthermore, the improvement of growth led to increases of not only yield components such as the total panicle number (TPN) and the number of spikelets in a panicle (NSP) in LTAT-29 but also the straw yield and quality of TAT-26. The lodging resistances of these forage rice plants were also improved due to the increased root development and photosynthesis creating tougher culms.

Automated summary

This study analyzed the effects of Bacillus pumilus strain TUAT1, a plant growth-promoting bacterium, on rice growth and yield. The results showed that the application of this strain significantly improved rice growth, nitrogen uptake, yield, and lodging resistance.