Vallejo Daniela A, García Julia E, Maroniche Guillermo A, Piccinetti Carlos F, Puente Mariana L, Rubio Esteban J, Groppa María D
Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Microbiología y Zoología Agrícola, Dr. Nicolás Repetto 2751, 1686, Hurlingham, Buenos Aires, Argentina.
Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata (UNMdP), Balcarce, Buenos Aires, Argentina.
Curr Microbiol. 2025 Sep 2;82(10):488. doi: 10.1007/s00284-025-04452-2.
Phosphorus is essential for plant growth, yet its availability in soils is extremely limited, with less than 0.1% accessible to plants. Though phosphate fertilizers are frequently employed to address this deficiency, a significant portion of the applied phosphorus is quickly fixed and unavailable to plants. Thus, the use of plant growth-promoting bacteria (PGPB) capable of solubilizing insoluble phosphate is an increasingly accepted eco-friendly agricultural practice to enhance phosphorus availability. This study aimed to isolate native phosphorus-solubilizing bacteria from lateritic and sandy soils of Misiones and Corrientes provinces (Argentina) and to study their plant growth-promoting attributes. Among the 17 isolates obtained following a selective protocol, two isolates, here named BVP24 and MMBR01, exhibited the highest phosphate solubilization activity (greater than other reported microorganisms) and produced substantial amounts of indole acetic acid. Both isolates were identified as Priestia megaterium via MALDI-TOF analysis and inhibited in vitro Fusarium graminearum growth. MMBR01 additionally inhibited Bipolaris sorokiniana growth. A dose of 1 × 10 CFU per seed was the most efficient to promote root dry weight in maize seedlings. Based on their plant growth-promoting capacities, these native strains emerge as potential biofertilizers, offering an alternative to synthetic phosphate fertilizers and contributing to more sustainable phosphorus management.
磷对植物生长至关重要，但其在土壤中的有效性极为有限，植物可利用的磷不足0.1%。尽管经常使用磷肥来解决这一不足，但施用的磷中有很大一部分会迅速被固定，植物无法利用。因此，利用能够溶解不溶性磷的植物促生细菌（PGPB）是一种越来越被认可的环保农业做法，以提高磷的有效性。本研究旨在从米西奥内斯省和科连特斯省（阿根廷）的红土和砂土中分离本地解磷细菌，并研究它们促进植物生长的特性。在通过选择性方案获得的17株分离物中，有两株分离物，这里命名为BVP24和MMBR01，表现出最高的解磷活性（高于其他报道的微生物），并产生大量吲哚乙酸。通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）分析，这两株分离物均被鉴定为巨大Priestia megaterium，并在体外抑制禾谷镰刀菌的生长。MMBR01还抑制了索氏炭疽菌的生长。每粒种子1×10 CFU的剂量对促进玉米幼苗根干重最为有效。基于它们促进植物生长的能力，这些本地菌株有望成为潜在的生物肥料，为合成磷肥提供替代方案，并有助于实现更可持续的磷管理。
