The role of Pasteuria penetrans in suppressing numbers of root-knot nematodes was investigated in a 7-year monocuhure of tobacco in a field naturally infested with a mixed population of Meloidogyne incognita race 1 and M. javanica. The suppressiveness of the soil was tested using four treatments: autoclaving (AC), microwaving (MW), air drying (DR), and untreated. The treated soil bioassays cons...

A polymerase chain reaction (PCR) method for discriminating Meloidogyne incognita, M. arenaria, M. javanica, M. hapla, and M. chitwoodi was developed. Single juveniles were ruptured in a drop of water and added directly to a PCR reaction mixture in a microcentrifuge tube. Primer annealing sites were located in the 3' portion of the mitochondrial gene coding for cytochrome oxidase subunit II and...

Cot curves derived from renaturation kinetics of sheared denatured DNA indicated that the genome of six populations representing the four most common root-knot nematode species (Meloidogyne incognita, M. arenaria, M. javanica, and M. hapla) is composed of 20% repetitive and 80% nonrepetitive sequences of DNA. Cot curves were almost identical, indicating that all populations had a haploid genome...

Thirty-six cultigens of tomato were evaluated for resistance against Meloidogyne javanica and four races of M. incognita with standards and parameters adopted by the International Meloidogyne Project. Most cultigens were susceptible to the nematodes, including some that were previously reported to be resistant to these nematodes. Ten accessions, namely Pusa-120, Calmart VFN, Panjab 6.NR-7, EC17...

Negative charges on the outer cuticular surface of Meloidogyne javanica females were visualized with electron microscope labelling techniques. Evidence is presented that the electronegative charge is not borne on neuraminic acid. Ruthenium red staining indicated acid mucopolysaccharides on the outer surface. A surface coat, or glycocalyx, external to the outer cuticle membrane was demonstrated.

The genus Meloidogyne is one of the most economically damaging plant parasitic nematodes on a worldwide basis. To date, only dragon fruits in Brazil were reported infected by M. javanica or incognita previous surveys. From 2019–2021, we conducted our investigation 62 orchards from 10 counties Hainan, which are main producing areas China. collected roots visually scored gall index to evaluate di...

Ninety-six isolates of Meloidogyne species collected from banana fields from Martinique, Guadeloupe, and French Guiana, were examined using esterase (Est) and malate dehydrogenase (Mdh) phenotypes. Adult females identified as M. arenaria, M. incognita, M. javanica, M. cruciani, M. hispanica, and Meloidogyne sp. showed species-specific phenotypes only for the esterase enzymes. Intraspecific vari...