Plant growth-promoting rhizobacteria mediated moisture stress alleviation in the early stages of Rice (Oryza sativa L.) variety CO 51

Abstract

Drought is one of the abiotic stresses that have a significant impact on agricultural growth across the world. Plant growth-promoting rhizobacteria (PGPR) inoculation in rice plants may be a viable and environmentally acceptable method of sustaining the development and yield of drought-stressed rice plants. The current study focused on the alleviation of drought in the early stages of rice variety CO 51 using PGPR isolated from the rhizosphere of xerophytes. The seeds were treated with bio inoculants and subjected to different moisture stress levels (10%, 20% and 30%) using PEG 6000. The seeds treated with bio inoculants exhibited higher germination percentage and growth traits such as shoot length root length and fresh weight, especially seeds treated with Bacillus velezensis VKSB5 (MT729963), and Bacillus altitudinis MLSB2 (MT729964) over uninoculated plants. This was found to be due to the increased proline accumulation and antioxidant activity in these seedlings, which plays a major role in drought alleviation by altering the osmotic potential and by its ROS scavenging mechanism. Hence this study provides evidence for the effective drought ameliorating ability of these cultures during the initial growth stages of rice. Further studies can contribute to the development of effective bio-inoculants for the mitigation of drought in rice.