The Response to Inoculation with PGPR Plus Orange Peel Amendment on Soybean Is Cultivar and Environment Dependent

Abstract

Plant growth-promoting rhizobacteria (PGPR) effects on plant yield are highly variable under field conditions due to competition with soil microbiota. Previous research determined that many Bacillus velezensis PGPR strains can use pectin as a sole carbon source and that seed inoculation with PGPR plus pectin-rich orange peel (OP) can enhance PGPR-mediated increases in plant growth. Because the previous studies used a single soybean cultivar, the objective of this research was to test the effect of PGPR plus OP inoculation on plant responses in a wide range of soybean cultivars. Preliminary screening with 20 soybean cultivars in the greenhouse showed that the PGPR plus OP produced a positive increase in all plant growth parameters when all cultivar data was averaged. However, when the inoculation response was examined cultivar by cultivar there was a range of cultivar response from a 60% increase in growth parameters to a 12% decrease, pointing to the presence of a cultivar-PGPR specificity. Further greenhouse and field experiments that studied cultivars with contrast responses to synbiotic inoculation revealed that the environment and/or the molecular interactions between the plant and microorganisms may play an important role in plant responsiveness.

Role of Endogenous Salicylic Acid as a Hormonal Intermediate in the Bacterial Endophyte Bacillus subtilis-Induced Protection of Wheat Genotypes Contrasting in Drought Susceptibility under Dehydration

“…Endophytic B. subtilis strains may be more effective at protecting plant growth under long-term stress conditions because the conditions inside the plant (stable pH, humidity, nutrient flux, and a lack of competition from many microorganisms) offer a stable host environment, allowing the bacteria to thrive and manifest their positive effects [ 28 , 29 ]. However, the behavior of any bacterial strain is at least partially dependent on the host species or varietal characteristics, geographic origin, environment, and stress type/level during growth [ 30 , 31 , 32 , 33 , 34 , 35 ]. It is crucial to understand the mechanisms that underlie the interactions between host plants and endophytic B. subtilis under drought.…”

Effects of Bradyrhizobium Co-Inoculated with Bacillus and Paenibacillus on the Structure and Functional Genes of Soybean Rhizobacteria Community

“…Previous studies have shown that inoculating soybean with PGPR can significantly change the soil microbial community structure, regulate soil physical and chemical properties and promote soybean growth [ 35 , 36 , 37 ]. The effect of PGPR on soil microorganisms is influenced by the type of PGPR, inoculation method and inoculum size [ 2 , 38 , 39 , 40 ]. In this study, it was found that the soil microbial structure could be significantly altered by the inoculation of compound microbial inoculum in the form of seed coating under the condition of no fertilization.…”

Molybdenum Nanofertilizer Boosts Biological Nitrogen Fixation and Yield of Soybean through Delaying Nodule Senescence and Nutrition Enhancement

“…For example, the single trait change via GE may not be sufficient to support the effectiveness of BNF, especially when plants are exposed to abiotic stresses. Similarly, the overall efficacy of coincubation with beneficial microorganisms is highly dependent on plant variety and microbial species, and negative impacts are common . Therefore, practical application has been limited due to a lack of understanding of variation across soybean varieties or the timing of inoculation and planting.…”

“…Similarly, the overall efficacy of coincubation with beneficial microorganisms is highly dependent on plant variety and microbial species, and negative impacts are common. 10 Therefore, practical application has been limited due to a lack of understanding of variation across soybean varieties or the timing of inoculation and planting. In addition, reduced effectiveness has been reported due to unsuitable environments, poor adaptation to the soil, and insufficient microorganism quality, among other issues.…”

“…Therefore, practical application has been limited due to a lack of understanding of variation across soybean varieties or the timing of inoculation and planting. In addition, reduced effectiveness has been reported due to unsuitable environments, poor adaptation to the soil, and insufficient microorganism quality, among other issues. , …”