Changes in DNA and RNA in roots of bur marigold fed upon by Longidorus africanus were studied using analytical methods, radioactive precursors, and analytical CsC1 density-gradient centrifugation. The analyses showed that almost twice as much RNA and DNA was present in parasitized root tips as in those of nonparasitized control plants. Studies on the rates of incorporation of labeled thymidine ...

Biochemical changes occurred in roots of bur marigold and grapevine infected with Longidorus africanus. Phenols of infected root tips differed quantitatively from those of healthy root tips (optical density of 0.68 and 0.32, respectively). Column chromatography of the phenol extracts resulted in more fractions in the infected than in the healthy root extract. Of the enzymes involved in phenol m...

The genus Longidorus includes a remarkable group of invertebrate animals of the phylum Nematoda comprising polyphagous root-ectoparasites of numerous plants including several agricultural crops and trees. Damage is caused by direct feeding on root cells as well as by transmitting nepoviruses that cause disease on those crops. Thus, correct identification of Longidorus species is essential to es...

Hierarchical cluster analysis based on female morphometric character means including body length, distance from vulva opening to anterior end, head width, odontostyle length, esophagus length, body width, tail length, and tail width were used to examine the morphometric relationships and create dendrograms for (i) 62 populations belonging to 9 Longidorus species from Arkansas, (ii) 137 publishe...

Plant-parasitic nematode population densities were determined from 325 root and soil samples collected from vegetable growing areas in Pakistan. Yield losses associated with nematode presence were quantified on 19 vegetable crops during 2007 and 2009. The most abundant plant-parasitic nematodes detected, in order of decreasing frequency of infestation (percentage of samples), were Meloidogyne i...

Pasteuria strain S-1 was found to parasitize the sting nematode Belonolaimus longicaudatus. S-1 spores attached to several strains of B. longicaudatus from different geographical locations within the United States. However, they did not adhere to any of the following species: Heterodera schachtii, Longidorus africanus, Meloidogyne hapla, M. incognita, M. javanica, Pratylenchus brachyurus, P. sc...

In a survey of ecotypes for longidorids, primarily from the rhizosphere hardwood trees growing in sandy soil along stream banks, 828 soil samples were collected from 37 Arkansas counties in 1999-2001. Eight populations of Longidorus breviannulatus were identified from the Arkansas survey samples. A total of 19 populations from California, Illinois, Iowa, Kansas, Michigan, Nebraska, New Jersey, ...