Effects of Bacterial and Fungal Inocula on Biomass, Ecophysiology, and Uptake of Metals of Alyssoides utriculata (L.) Medik.

Abstract

The inoculation of plants with plant-growth-promoting microorganisms (PGPM) (i.e., bacterial and fungal strains) is an emerging approach that helps plants cope with abiotic and biotic stresses. However, knowledge regarding their synergic effects on plants growing in metal-rich soils is limited. Consequently, the aim of this study was to investigate the biomass, ecophysiology, and metal accumulation of the facultative Ni-hyperaccumulator Alyssoides utriculata (L.) Medik. inoculated with single or mixed plant-growth-promoting (PGP) bacterial strain Pseudomonas fluorescens Migula 1895 (SERP1) and PGP fungal strain Penicillium ochrochloron Biourge (SERP03 S) on native serpentine soil (n = 20 for each treatment). Photosynthetic efficiency (Fv/Fm) and performance indicators (PI) had the same trends with no significant differences among groups, with Fv/Fms > 1 and PI up to 12. However, the aboveground biomass increased 4–5-fold for single and mixed inoculated plants. The aboveground/belowground dry biomass ratio was higher for plants inoculated with fungi (30), mixed (21), and bacteria (17). The ICP-MS highlighted that single and mixed inocula were able to double the aboveground biomass’ P content. Mn metal accumulation significantly increased with both single and mixed PGP inocula, and Zn accumulation increased only with single PGP inocula, whereas Cu accumulation increased twofold only with mixed PGP inocula, but with a low content. Only Ni metal accumulation approached the hyperaccumulation level (Ni > 1000 mg/kg DW) with all treatments. This study demonstrated the ability of selected single and combined PGP strains to significantly increase plant biomass and plant tolerance of metals present in the substrate, resulting in a higher capacity for Ni accumulation in shoots.

Use of bacterial inoculation to improve vegetative growth and nutraceutical qualities of Chinese cabbage under regulated agroecosystem conditions

“…Одним из подходов, который может быть использован для решения некоторых текущих проблем сельского хозяйства, является выращивание растений в закрытых агроэкосистемах с применением полезных микроорганизмов. Инокуляция растений PGPR-бактериями (от Plant Growth Promoting Rhizobacteria -ризобактерии, способствующие росту растений) -новый подход, который основан на использовании потенциала растений и микроорганизмов за счет биологических механизмов взаимодействия между компонентами растительномикробных систем [6]. Одной из наиболее важных черт штаммов, способствующих росту растений, является повышение биодоступности необходимых элементов, таких как P, K и Fe.…”