This study is aimed at assessing the ability of two endophytic bacteria originally isolated from healthy oil palm roots, Pseudomonas sp. (UPMP3) and Burkholderia sp. (UPMB3) to induce resistance in susceptible Berangan banana against Fusarium oxysporum race 4 (FocR4). Increased accumulation of resistance-related enzymes such as peroxidase (PO), phenylalanine ammonia lyase (PAL), lignithioglycolic acid (LTGA), and pathogenesisrelated (PR) proteins (chitinase and β-1,3-glucanase) has been observed in plantlets treated with endophytic bacteria UPMP3 and UPMB3 singly or as mixture under glasshouse conditions. Pre-inoculation of banana plantlets with UPMP3 showed a significant reduction in Fusarium wilt incidence 72 d after challenged inoculation with FocR4. UPMB3 was less effective in suppressing Fusarium wilt compared to UPMP3, whereas, the mixture of both endophytes showed an intermediate effect. Based on these results, it is concluded that UPMP3 could be a promising biological control agent that can trigger resistance against Fusarium wilt in susceptible Berangan banana.

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Phosphate solubilizing bacteria (PSB) can convert insoluble form of phosphorous to an available form. Applications of PSB as inoculants increase the phosphorus uptake by plant in the field. In this study, isolation and precise identification of PSB were carried out in Malaysian (Serdang) oil palm field (University Putra Malaysia). Identification and phylogenetic analysis of 8 better isolates were carried out by 16S rRNA gene sequencing in which as a result five isolates belong to the Beta subdivision of Proteobacteria, one isolate was related to the Gama subdivision of Proteobacteria, and two isolates were related to the Firmicutes. Bacterial isolates of 6upmr, 2upmr, 19upmnr, 10upmr, and 24upmr were identified as Alcaligenes faecalis. Also, bacterial isolates of 20upmnr and 17upmnr were identified as Bacillus cereus and Vagococcus carniphilus, respectively, and bacterial isolates of 31upmr were identified as Serratia plymuthica. Molecular identification and characterization of oil palm strains as the specific phosphate solubilizer can reduce the time and cost of producing effective inoculate (biofertilizer) in an oil palm field.

Ralstonia solanacearum, a soil-borne plant pathogen, causes lethal wilting disease of more than 200 plants worldwide. This very wide host range covers both monocots and dicots, extending from annual plants to trees and shrubs. Although generally it's considered as a plant pathogen, R. solanacearum behaves primarily as a saprophytic bacterium able to survive for long periods of time in various natural habitats such as surface waters and different types of soils. Epidemiological and ecological studies on pathogen distribution in the environment are seriously hindered by the lack of efficient detection method especially when the concentration of the pathogen is either very low or is present in a latent, dormant or non-culturable state. With due attention to importance of R. solanacearum in Malaysia and several irreparable losses that every year caused by this bacterium, this is prompted current study to develop a sensitive PCR-Based method to improve the detection of R. solanacearum in natural sources. We selected the previously reported primers (OLI1;OLI2; Y2; JE2) for their sensitivity and specificity detection of the bacterium in water and soil by a modification of PCR assay.

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