Sustainable agriculture requires nutrient management options that can increase crop yields that are profitable for N nutrient availability and are environmentally friendly. However, N nutrient is dynamic and easy to lose, and excessive use of chemical N fertilizers has a negative impact on the environment. Biofertilizer by rhizobacteria is an effective way to maintain a reliable N-supply for rice growth. This study investigates the effect of a different combination of rhizobacterial fertilizers on nitrogen ion concentration in the soil and total rice production. The field experiment was conducted in two seasons. There were three treatments, including PGPR with 25% CF, PGPR with 50% CF, and 100% CF. The soil sample was taken from each treatment in six growth stages of rice i.e. 15, 36, 50, 72, 100, and 118 days after transplanting. Soil chemicals NH 4 + and NO 3were analyzed by Ion Chromatography. The results showed that the uniformity of NH 4 + and NO 3 in the soil were the highest in fertilizer application with PGPR. The application of PGPR with 50% CF confirms that it can increase rice yields by 25.5% and 12.9%, respectively. The application of rhizobacteria can reduce the use of chemical fertilizers.

The interaction between plant roots and rhizobacterium communities plays a crucial role in sustainable agriculture. We aimed to assess the effects of Sphingobium yanoikuyae SJTF8 on rice seed germination and development, as well as to observe the effects of different concentrations of S. yanoikuyae SJTF8 on the root systems of rice seedlings. The bacteria are best known for their role in the bioremediation and biodegradation of pollutants, and thus far, there is research that supports their agricultural prospects. The experiment comprised five different S. yanoikuyae SJTF8 concentrations: SP-y 8 (108 CFU/mL); SP-y 7 (107 CFU/mL); SP-y 6 (106 CFU/mL); SP-y 5 (105 CFU/mL); SP-y 4 (104 CFU/mL). We used sterilized water as the control treatment. The bacteria triggered the synthesis of IAA, while the seedling root lengths substantially increased on the 12th day after germination. The high application concentrations of S. yanoikuyae SJTF8 resulted in higher IAA production (with the SP-y 7 and SP-y 8 concentrations ranging from 151,029 pg/mL to 168,033 pg/mL). We found that the appropriate concentrations of S. yanoikuyae SJTF8 when applied as an inoculant were SP-y 7 and SP-y 6, based on the increased root growth and biomass production. The bacteria were also able to solubilize phosphorous. The growth response from the rice seedlings when inoculated with S. yanoikuyae SJTF8 presents the potential of the bacteria as a growth promotor. Its application in rice cultivation could be a sustainable approach to rice production.