Combined Use of Novel Endophytic and Rhizobacterial Strains Upregulates Antioxidant Enzyme Systems and Mineral Accumulation in Wheat

Abstract

Wheat is the third largest grown crop after maize and rice worldwide. Integrated use of chemical and biofertilizers have the potential to improve crop yield and quality due to their growth-promoting attributes. Therefore, the present study planned to evaluate the effectiveness of endophytic (Paenibacillus sp. strain (ZE11), Bacillus subtilis (ZE15) and Bacillus megaterium (ZE32)) and rhizobacterial strains (Bacillus subtilis (ZR2) Bacillus subtilis (ZR3) and Bacillus megaterium strain (ZR19)), solely and in combination, to increase the productivity of wheat and microbial activity in the rhizosphere. The maximum increase in microbial biomass carbon (44%), available phosphorous (30%), ammonium–nitrogen (24%), nitrate–nitrogen (37%), iron (10%), zinc (11%) and bacterial population (31%) was recorded by co-inoculation of ZE11 + ZR3. Subsequently, co-inoculation of ZE11+ZR3 showed a maximum increase of 31%, 29%, 30%, 27%, 33%, 30%, 25%, 9%, 15%, 9%, 18% and 26% in superoxidase dismutase (SOD), peroxidase dismutase (POD), catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO) and peroxidase (POX), grain yield, nitrogen, phosphorous, potassium, iron and zinc in grains, respectively, as compared to uninoculated control. The sole inoculation of ZR19 showed maximum harvest index (45.5%). The sole inoculation of endophytes and rhizobacteria has a significant effect on growth, physiology, and wheat crop yield. However, co-inoculation had a better effect and can be used to develop multi-strain biofertilizer to promote growth and yield of crops.

Bacillus Strains with Catalase Enzyme Improve the Physiology and Growth of Rice (Oryza sativa L.)

“…The bacterial population improved the amounts of nitrate-nitrogen, ammonium-nitrogen, and microbial biomass carbon [39]. This was also reported by Iqbal et al [40]. The treatments applied in our study showed a remarkable improvement in microbial carbon biomass and act as substrate for nutrient availability in soils, hence improving their biochemical properties and organic matter.…”

The Effect of Different Carrier Materials on the Growth and Yield of Spinach under Pot and Field Experimental Conditions

“…Similar findings were observed by Hammad et al [61], who used organic waste for the application of the PGPR consortium and found that the growth-promoting traits of the PGPR, such as miners solubilization, indole acetic acid (IAA) production, and siderophore production, not only enhanced the chlorophyll, MSI, RWC, and mineral nutrients, but also biofortify okra with Zn and Fe. The reason for this might be that the use of organic carriers with entrapped nutrients and microorganisms solubilizes mineral nutrients by secreting organic acids in the rhizosphere of spinach [62].…”

“…All of the carrier materials significantly enhanced the microbial population, but the treatment with peat had the maximum microbial count as compared to the other organic carriers. The reason for this might be the provision of a large surface area for microbial attachment to peat, their compatibility, and the ease of degrading the peat to attain energy and nutrients for their population growth, even under harsh climatic conditions [62]. The improved bacterial population is responsible for the enhanced-growth promoting activities, i.e., mineral solubilization, nutrient uptake, root proliferation, and water for better crop growth, as well as physiological trait improvements and, ultimately, yield improvement [70,71].…”

The Use of Biofertilizers of Microbial Origin to Increase the Yield of Oil Flax and Spring Barley in the Conditions of Northern Kazakhstan

“…To increase the natural fertility of the soil, it is necessary to introduce new technologies using biofertilizers of microbial origin to ensure the stability of crops. Currently, researchers around the world are paying attention to this issue [14][15][16].…”