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Plant growth-promoting rhizobacteria (PGPR) are rapidly emerging as a sustainable substitute for synthetic chemical fertilizers and pesticides in modern agriculture. PGPR is a group of microbial that have been screened for its nitrogen fixation ability, phosphate solubilization, potassium solubilization (see Figure 1). The utilization of PGPR results in a multitude of advantages, including increased plant growth, higher nutrient absorption, and fewer negative effects on the surrounding environment. These beneficial microbes foster a good environment within the rhizosphere by building a symbiotic relationship with plants. This relationship ultimately results in outstanding achievements. The ability of PGPR to proficiently synthesize important plant growth regulators, such as indole-acetic acid (IAA), is an example of the natural ability of PGPR to stimulate plant development and health. The consequent increase in root development and nutrient assimilation accelerates plant health to new heights. In addition, the ability of PGPR to dissolve essential nutrients like phosphorus and potassium makes these essential nutrients more available to plants. This is an important benefit. This capability is of especially crucial in soils that are deficient in nutrients since nutrient solubilization driven by PGPR has the potential to significantly improve plant nutrition and increase crop yields in these soils. 

Beyond nutrition augmentation, PGPR function as plant protectors, strengthening their defences against diseases and abiotic stresses. One of their most significant qualities is their capacity to stimulate systemic resistance in plants, which successfully fortifies the plants against the invasion of many diseases and pests. The influence of PGPR extends to the regulation of osmotic equilibrium and antioxidant activity, increasing plant tolerance to adverse situations such as drought, salt, and heavy metal toxicity. This naturally occurring resilience fits in perfectly with the overarching goal of reducing the negative effects of climate change on agricultural output. The increasing use of PGPR-based biofertilizers reflects the growing trend toward sustainable agriculture practices. These formulations, which are loaded with useful microbes such as PGPR, promote enhanced nutrient availability and increased plant development. The environmental benefits of biofertilizers are numerous, including soil health preservation and pollution reduction by eliminating the need for chemical fertilizers and pesticides. In addition, biofertilizers play the role of catalysts in the process of improving soil by nourishing soil structure, encouraging microbial diversity, and increasing fertility. The effectiveness of PGPR can be improved with the application of cutting-edge methods like encapsulation. By encapsulating these bacteria in alginate beads, chitosan, and polysaccharides, their survivability and controlled release within the rhizosphere is considerably improved. Notably, additional soil conditioners such as biochar can be used within the encapsulation process to achieve synergistic benefits (see Figure 2). This encapsulation approach extends the duration of PGPR activity, allowing for the slow release of beneficial chemicals that further galvanize plant development. Simultaneously, this encapsulating approach enables PGPR to establish colonies in the rhizosphere and survive the most severe environmental conditions. 

The rise of PGPR in the field of sustainable agriculture offers a promising alternative to more traditional methods of crop production. In Malaysia, the use of PGPR has resulted in significant favourable benefits on essential crops such as rice, chilli, and ginger. The use of PGPR in rice farming has resulted in increased nutrient solubilization, notably phosphorus and potassium, which has resulted in higher nutrient absorption and systemic resistance induction. This, in turn, leads to increased yields and production. Similarly, in chilli agriculture, PGPR application has shown the potential to increase fruit yield through enhanced nutrient availability and strong root growth resulting in healthier plants and lower disease susceptibility. The symbiotic relationship developed by these beneficial bacteria results in a variety of favourable effects, ranging from increased plant growth and improved nutrient absorption to strengthened plant defence mechanisms and reduced dependency on chemical inputs. PGPR's contribution to the agricultural landscape essentially reflects the beneficial relationship between nature and innovation.