Abstract
The red ring nematode (Bursaphelenchus cocophilus (Cobb) Baujard 1989) has been registered in oil palm crops in the North, Central and Eastern zones of Colombia. In Tibu (North Santander), there are doubts regarding the diagnostic and identity of the disease. Oil palm crops in Tibu with the external and internal symptoms were inspected, and tissue samples were taken from different parts of the palm. The refrigerated samples were carried to the laboratory of Oleoflores in Tibu for processing. The light microscopy was used for the quantification and morphometric identification of the nematodes. Specimens of the nematode were used for DNA extraction, to amplify the segment D2-D3 of the large subunit of ribosomal RNA (28S) and perform BLAST and a phylogeny study. The most frequently symptoms were chlorosis of the young leaves, thin leaflets, collapsed, and dry lower leaves, beginning of roughening, accumulation of arrows and short leaves. Bursaphelenchus, was recovered in most of the tissues from the samples analyzed: stem, petiole bases, inflorescences, peduncle of bunches, and base of arrows in variable populations. The morphometric data and sequences obtained for the segment D2-D3 confirms to B. cocophilus as the causal agent of red ring disease on oil palms in the study area. For our knowledge, this study reports the first partial sequences of segment D2-D3 of B. cocophilus in oil palm in Colombia.