Further observations on Meloidogyne enterolobii (Nematoda: Meloidogynidae) infecting guava (Psidium guajava) in India

Characterization of Meloidogyne enterolobii intercepted from baobab (Adansonia digitata L.) seedlings from Thailand during Japanese import plant quarantine inspection

In April 2019, baobab (Adansonia digitata L.) seedlings from Thailand, exhibiting galls on the roots, were intercepted during an import plant quarantine inspection at Chubu Centrair International Airport, Japan. Root-knot nematodes (RKNs) were extracted from the galled roots of baobab seedlings and identified by morphological, morphometrical and molecular methods as the guava root-knot nematode, Meloidogyne enterolobii Yang & Eisenback. The morphology and morphometrics of the intercepted population were similar to those of the original and subsequent descriptions of M. enterolobii. The sequences of D2-D3 of 28S rRNA, mtDNA intergenic COII-16S rRNA and COI genes obtained in this study matched well (99-100% similarity) with each of the gene sequences of M. enterolobii deposited in GenBank. Phylogenetic analysis of these genes revealed that the intercepted population clustered with M. enterolobii and clearly differed from other RKN species. To the best of our knowledge, this is the first report of M. enterolobii from baobab.

Meloidogyne enterolobii risk to agriculture, its present status and future prospective for management

Meloidogyne enterolobii, commonly known as guava root-knot nematode, poses risk due to its widespread distribution and extensive host range. This species is recognized as the most virulent root-knot nematode (RKN) species because it can emerge and breed in plants that have resistance to other tropical RKNs. They cause chlorosis, stunting, and yield reductions in host plants by producing many root galls. It is extremely challenging for farmers to diagnose due to the symptoms' resemblance to nutritional inadequacies. This pathogen has recently been considered a significant worldwide threat to agricultural production. It is particularly challenging to diagnose a M. enterolobii due to the similarities between this species and other RKN species. Identified using traditional morphological and molecular techniques, which is a crucial first in integrated management. Chemical control, biological control, the adoption of resistant cultivars, and cultural control have all been developed and effectively utilized to combat root-knot nematodes in the past. The object of this study was to get about the geographical distribution, host plants, symptoms, identification, and control techniques of M. enterolobii and recommend future initiatives to progress its management.