Potential Novel Plant Growth Promoting Rhizobacteria for Bio-Organic Fertilizer Production in the Oil Palm (_Elaeis guineensis_ Jacq.) in Malaysia  
[PERSON]  
1 Department Land Management, Faculty of Agriculture, Universiti Putra Malaysia,  
43400 UPM Serdang, Selangor, Malaysia  
2 All Cosmos Bio-Tech Holding Corporation, PLO650, Jalan Keluli, Pasir Gudang Industrial Estate,  
Pasir Gudang B1700, Johor, Malaysia; [EMAIL_ADDRESS]  
[PERSON]  
2 All Cosmos Bio-Tech Holding Corporation, PLO650, Jalan Keluli, Pasir Gudang Industrial Estate,  
Pasir Gudang B1700, Johor, Malaysia; [EMAIL_ADDRESS]  
[PERSON]  
3 Department of Agriculture Technology, Faculty of Agriculture, Universiti Putra Malaysia,  
43400 UPM Serdang, Selangor, Malaysia; [EMAIL_ADDRESS]  
[PERSON]  
4 Department of Crop Science, Faculty of Agriculture, University Putra Malaysia,  
43400 UPM Serdang, Selangor, Malaysia; [EMAIL_ADDRESS]  
[PERSON]  
1 Department Land Management, Faculty of Agriculture, Universiti Putra Malaysia,  
43400 UPM Serdang, Selangor, Malaysia  
72.27 million metric tonnes, with the Southeast Asian countries (Indonesia and Malaysia) as the major global exporters of palm oil [4]. Basal stem rot incidence in oil palms was reported to significantly decrease due to the chemical treatment such as fungicides [5]. Yet, because they inhibit the formation of beneficial microbes, these biocidal chemical compound fungicides are not eco-friendly and can be highly toxic to the plantation ecosystem [6]. Concerns about the detrimental effects of chemical fertilizers have prompted new studies, such as biofertilizers, as free-living nitrogen-fixing bacteria into ecological crop management strategies have been carried out [7]. Therefore, the alternative fertilizer, such as a combination with bio-based, will be more useful in the long run [1]. Due to the high nutritional needs and high expense of chemical fertilizers for oil palm trees, producers have been looking for lower-priced options that allow for more efficient nutrient utilization. As a result, agricultural experts are looking at biofertilizers, which are cost-effective [8; 9; 10]. Biofertilizers are fertilizers that contain living microorganisms that boost soil microbial activity. They are renewable low-cost nutrient sources that can substitute for chemical fertilizers in an eco-friendly manner [11; 12]. Biofertilizers are plant-nourishing organic fertilizers that are simple to make and can be applied feasibly in the oil palm plantation area [13]. Compared to the control tea plants. [PERSON] et al. [14] found inoculants of _Pseudomonas corrugate_ and _Bacillus subtilis_ could increase host plant survival by 88% and 100%, respectively. The inoculation of chosen diazotrophic rhizobacteria into the tissues of oil palm during in vitro micropropagation would allow for premature relationships between the host and the bacteria. These positive relationships would allow the host plants to better adjust to environmental conditions/stresses so as to have a better survivorship [15; 16]. Furthermore, because the diazotroph can fix nitrogen in situ, the bacterized plants require very little nitrogen fertilizer [16; 17]. Finally, diazotrophs generate plant growth hormones that will help in roots' development and the overall plants' growth [18]). Therefore, the plant growth-promoting rhizobacteria (PGPR) are the important and agronomically helpful soil microbiota [19] that would be colonizing in the plant's roots and consequently stimulate the plant's growth [20]. The PGPR (in the rhizosphere of plants) would promote their hosts' growth and development of the plants. The root system acts as a massive anchor for nutrient and water intake and a chemical factory for beneficial microorganisms, rhizobia, mycorrhizae, endophytes, and PGPRs, as well as parasitic connections with other plants [21]. The PGPR can decrease the requirement for inorganic fertilizer, particularly for nitrogen and phosphorus, and increasing the nutrient release needed by oil palm [22].