Identification and Characterization of Bacterial Community Associated with the Chewed Feeding Waste of Red Palm Weevil in Infested Date Palm Trees

Abstract

Red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), is considered one of the most damaging insect pests of date palms in the Kingdom of Bahrain. Large scale infestation of RPW to date palm trees leads to excessive feeding activity of the RPW larvae, which is carried out by microorganisms present within RPW and producing a wet fermenting material inside the trunk. Culture dependent-bacteria were isolated from feeding waste and identified by the sequencing of the 16S rRNA gene using 8F and 1492R universal primers. Among the culture-dependent isolated bacteria, 80% were identified by comparing 16S rRNA gene sequence in NCBI database, using BLAST program in GenBank. 85% of the identified bacteria were Gram-positive while the rest of them were Gram-negative. A high abundance of bacteria were from the Bacillaceae family and sixteen different species of Bacillus were identified in comparison with NCBI GenBank. The 16S rRNA gene sequences of identified bacterial strains have been submitted to GenBank. The phylogenetic relationship was studied using 16S rRNA gene sequences, the Gram-negative bacteria came in one clade while Gram-positive different Bacillus sp. and strains showed evolutionary closeness to each other and accordingly, they came in one major clade under three different sub-clades in the phylogenetic tree. The findings of new Bacillus strains in the natural habitat of the date plam trees in the Kingdom of Bahrain, pledge a vast area of research on RPW bio-control research arena.