RESUMO
Lysinibacillus is a bacterial genus that has generated recent interest for its biotechnological potential in agriculture. Strains belonging to this group are recognized for their mosquitocidal and bioremediation activity. However, in recent years some reports indicate its importance as plant growth promoting rhizobacteria (PGPR). This research sought to provide evidence of the PGP activity of Lysinibacillus spp. and the role of the indole-3-acetic acid (IAA) production associated with this activity. Twelve Lysinibacillus spp. strains were evaluated under greenhouse conditions, six of which increased the biomass and root architecture of corn plants. In most cases, growth stimulation was evident at 108 CFU/mL inoculum concentration. All strains produced IAA with high variation between them (20-70 µg/mL). The bioinformatic identification of predicted genes associated with IAA production allowed the detection of the indole pyruvic acid pathway to synthesize IAA in all strains; additionally, genes for a tryptamine pathway were detected in two strains. Extracellular filtrates from all strain's cultures increased the corn coleoptile length in an IAA-similar concentration pattern, which demonstrates the filtrates had an auxin-like effect on plant tissue. Five of the six strains that previously showed PGPR activity in corn also promoted the growth of Arabidopsis thaliana (col 0). These strains induced changes in root architecture of Arabidopsis mutant plants (aux1-7/axr4-2), the partial reversion of mutant phenotype indicated the role of IAA on plant growth. This work provided solid evidence of the association of Lysinibacillus spp. IAA production with their PGP activity, which constitutes a new approach for this genus. These elements contribute to the biotechnological exploration of this bacterial genus for agricultural biotechnology.
Assuntos
Arabidopsis , Bacillaceae , Ácidos Indolacéticos/metabolismo , Desenvolvimento Vegetal , Bactérias/metabolismo , Bacillaceae/genética , Bacillaceae/metabolismo , Arabidopsis/metabolismo , Plantas/metabolismo , Raízes de Plantas/microbiologiaRESUMO
Microwaves have been applied to the drying of seeds of several species due to their maintenance of the quality of the seeds and reduction of time and costs. However, few is known about the effect of microwaves on the increase of the physiological quality of soybean seeds and especially their effects on longevity. Therefore, the use of microwaves as magneto-priming in soybean seeds was the object of study in this work. For this purpose, two soybean cultivars were selected and submitted to the ultra-high frequency (UHF) microwave exposure of 2.45 GHz, in the wavelength of 11 cm, and power of 0.2 W/g, for 15 min. The results showed that this condition of exposure to the microwave brought benefits in both cultivars after treatment. Incremental improvements were observed in the germinability indexes, the seedling length, the water absorption by the seeds, the fresh mass, dry mass, and longevity. The genes related to seed germination and longevity showed superior expression (HSFA3, HSP21, HSP17.6b, EXP, ABI3) with magneto-priming treatment. The data found ensure the use of the technique as a viable option for pre-treatment as magneto-priming in soybean seeds in order to improve seed quality.
RESUMO
RESUMEN El envejecimiento es un proceso complejo que trae consigo cambios celulares, histológicos y cutáneos. Estos últimos son una de sus manifestaciones más evidentes. El plasma rico en plaquetas es una fuente fiable de obtención de células para regenerar tejidos; por su fácil disponibilidad es un material inocuo. La bioestimulación con el mismo, por su parte, es un conjunto de procedimientos para activar las funciones anabólicas de los fibroblastos, producción de colágeno, elastina y ácido hialurónico. La tendencia al empleo de este en tratamientos antiedad es cada vez mayor. El objetivo de este trabajo fue realizar una actualización del tema, para exponer aspectos importantes sobre formas de aplicación, indicaciones, complicaciones y contraindicaciones. Existen varios métodos para la bioestimulación facial, tales como la realización de pápulas, napagge y retroinyección. Se han empleado en alopecia androgénica, areata, envejecimiento cutáneo, etc. Las complicaciones más observadas son dolor, eritema, ardor y sangrado local. Entre las contraindicaciones más comunes se observan el herpes simple recidivante, coagulopatías, tratamiento con anticoagulantes, colagenopatías y neoplasias (AU).
ABSTRACT Aging is a complex process that brings with it cellular, histological and cutaneous changes, the latter being one of its most obvious manifestations. Platelet-rich plasma is a reliable source of cells to regenerate tissues; due to its easy availability, it is a harmless material. Bio-stimulation with it is a set of procedures to activate the fibroblasts anabolic functions and the production of collagen, elastin and hyaluronic acid. The tendency to use it in anti-aging treatments increases faster and faster. The objective of this work was updating the topic to expose important aspects about application methods, indications, complications and contraindications. There are several methods of applying facial bio-stimulation such as performing papules, napagge, and retroinjection. It has been used in androgenic alopecia, alopecia areata, cutaneous ageing, etc. The most commonly found complications are pain, erythema, burning and local bleeding. The most common contraindications include recidivist herpes simplex, coagulopaties, anticoagulant treatment, collagen-related diseases and neoplasms (AU).