Rahnella aquatilis AZO16M2, was characterized for its phosphate solubilization capacity to improve the establishment and survival of Musa acuminata var. Valery seedlings under ex-acclimation. Three phosphorus sources (Rock Phosphate (RF), Ca3(PO4)2 and K2HPO4) and two types of substrate (sand:vermiculite (1:1) and Premix N°8) were selected. The factorial analysis of variance (p < 0.05) showed that R. aquatilis AZO16M2 (OQ256130) solubilizes Ca3(PO4)2 in solid medium, with a Solubilization Index (SI) of 3.77 at 28 °C (pH 6.8). In liquid medium, it was observed that R. aquatilis produced 29.6 mg/L soluble P (pH 4.4), and synthesized organic acids (oxalic, D-gluconic, 2-ketogluconic and malic), Indole Acetic Acid (IAA) (33.90 ppm) and siderophores (+). Additionally, acid and alkaline phosphatases (2.59 and 2.56 µg pNP/mL/min) were detected. The presence of the pyrroloquinoline-quinone (PQQ) cofactor gene was confirmed. After inoculating AZO16M2 to M. acuminata in sand:vermiculite with RF, the chlorophyll content was 42.38 SPAD (Soil Plant Analysis Development). Aerial fresh weight (AFW), aerial dry weight (ADW) and root dry weight (RDW) were superior to the control by 64.15%, 60.53% and 43.48%, respectively. In Premix N°8 with RF and R. aquatilis, 8.91% longer roots were obtained, with 35.58% and 18.76% more AFW and RFW compared with the control as well as 94.45 SPAD. With Ca3(PO4)2, values exceeded the control by 14.15% RFW, with 45.45 SPAD. Rahnella aquatilis AZO16M2 favored the ex-climatization of M. acuminata through improving seedling establishment and survival.

Resumen En el presente estudio, se seleccionaron e identificaron bacterias de ácido láctico (BAL) productoras de riboflavina, aisladas durante el proceso de elaboración de Tunta, una patata nativa peruana con un proceso tradicional de congelación y deshidratación para el consumo y conservación. De las 109 cepas BAL aisladas, 32 fueron las que presentaron producción de riboflavina y sólo cuatro mostraron un nivel alto entre 334 ng/ml a 426 ng/ml en medio libre de riboflavina. La caracterización molecular de estas cuatro cepas mostró que están relacionados filogenéticamente con Leuconostoc mesenteroides. Otros taxones identificados tras la secuenciación del gen 16S rRNA fueron Lactobacillus curvatus, L. mesenteroides subsp. dextranicum y Lactobacillus sakei. Posteriores estudios con estas cepas BAL productoras de riboflavina permitirán revalorizar los nutrientes de la Tunta como alimento nativo del Perú. Palabras clave: bacterias ácido lácticas (BAL), gen ribosómico 16s Rrna, riboflavina, tunta, Jallamilla.