ABSTRACT

This investigation was conducted to determine the ability of plant growth-promoting rhizobacteria (PGPR) to elicit growth of rice plants (var. CO51) in soil incubated with Blue-R textile dye. Two commercial strains of PGPR, nitrogen-fixing Azospirillum lipoferum Az204 and phosphorus-solubilizing Bacillus megaterium var phosphaticum PSB1, were used to prepare a carrier and liquid-based formulations. Seed biotization of carrier-based PGPR consortium followed by a foliar spray substantially resulted in a higher plant biomass, germination percent, and vigor index as compared to non-inoculated plants in Blue-R-amended soil. The photosynthetic efficiency is also higher, which is evident by the total chlorophyll content in PGPR-treated seedlings. Similarly, the carrier-based PGPR inoculated plants revealed higher nutrient uptake as well as N, P, and K content in shoots as compared to the non-inoculated plants. PGPR inoculation through seeds showed better survival and colonization of A. lipoferum Az204 and B. megaterium PSB1 in the rhizosphere. A. liopferum Az204 remarked good colonization in inner tissues of roots, stems, and leaves. It was concluded that PGPR application through seeds enhances crop fitness, modulates rhizosphere services, and alleviates oxidative stress caused by Blue-R in rice plants. Therefore, rhizosphere engineering by PGPR through seeds followed by subsequent foliar sprays can be used as a sustainable strategy for textile wastewater-irrigated soils.

摘要

本研究旨在确定植物生长促进根际细菌 (PGPR) 在与 Blue-R 纺织染料孵育的土壤中诱导水稻植物 (var. CO51) 生长的能力。PGPR的两种商业菌株，固氮Azospirillum lipoferum Az204和磷溶解巨大芽孢杆菌PSB1，用于制备载体和液体制剂。与 Blue-R 改良土壤中的未接种植物相比，基于载体的 PGPR 联合体的种子生物化，然后进行叶面喷雾，显着提高了植物生物量、发芽率和活力指数。光合效率也更高，这从 PGPR 处理的幼苗中的总叶绿素含量可以看出。同样，与未接种的植物相比，基于载体的 PGPR 接种植物显示出更高的养分吸收以及芽中的 N、P 和 K 含量。通过种子接种 PGPR 表明A. lipoferum Az204 和B. megaterium PSB1 在根际的存活和定殖更好。A. lipoferumAz204 在根、茎和叶的内部组织中具有良好的定殖性。得出的结论是，通过种子施用 PGPR 可增强作物适应性，调节根际服务，并减轻 Blue-R 对水稻植物造成的氧化应激。因此，PGPR 通过种子进行根际工程，然后进行叶面喷雾，可以作为纺织废水灌溉土壤的可持续策略。