Tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to Meloidogyne incognita in the greenhouse. Tall fescue cultivars evaluated included, i) wild-type Jesup (E+, ergot-producing endophyte present), ii) endophyte-free Jesup (E-, no endophyte present), iii) Jesup (Max-Q, non-ergot producing endophyte) and iv) Georgia 5 (E+). Peach was included as the con...

The early events of Meloidogyne incognita behavior and associated host responses following root penetration were studied in resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa. Ten-day-old seedlings of alfalfa cultivars were inoculated with second-stage juveniles (J2) and harvested 12, 24, 48, and 72 hours and 7, 14, and 21 days later. Both cultivars supported similar root penetrati...

The host suitability of 64 commercial corn hybrids for a Meloidogyne arenaria race 2 population and a M. incognita race 4 population was determined in greenhouse experiments. 'Northrup King 508' and 'Pioneer Brand 3147' maintained M. arenaria below and at the initial population level, respectively, indicating that these hybrids are relatively poor hosts for this species. RF values (final egg nu...

Egg masses of Meloidogyne incognita and M. hapla were placed in soil at 10, 12, 16, and 20 C. At regular intervals, eggs from samples of egg masses were released from the gelatinous matrices and their developmental stages recorded. The number of days necessary to complete each stage from gastrulation to hatch is given for each temperature. The minimal temperature threshold for the development o...

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...

Research was initiated to physically characterize the mitochondrial genomes of several Meloidogyne spp. and host-races, to address questions regarding their systematics and dispersal, and to assess the possibility of developing molecular diagnostics for these nematodes. Techniques were developed for purification and rapid detection of mitochondrial DNA from root-knot nematodes. Mitochondrial DN...

The root knot nematodes (RKN), Meloydogine spp., particularly Meloidogyne incognita and Meloidogyne javanica species, parasitize several plant species and are responsible for large annual yield losses all over the world. Only a few available chemical nematicides are still authorized for RKN control owing to environmental and health reasons. Thus, plant resistance is currently considered the met...

Algal extracts were ineffective against Meloidogyne spp., Panagrellus redivivus, and Neoaplectana carpocapsae at 1.0% aqueous concentrations, with the exception of Spatoglossum schroederi. S. schroederi killed Meloidogyne incognita, M. javanica, M. acrita, and Hoplolaimus galeatus at concentrations of 1.0, 0.75, and 0.50%. Extracts from S. schroederi at a concentration of 1.0% were ineffective ...

While sexual reproduction is generally thought to be, evolutionarily speaking, a good idea, there are a small number of organisms that are testament to the contrary. The root-knot nematodes Meloidogyne incognita, M. javanica, and M. arenaria reproduce clonally using mitotic parthenogenesis but have a broader host range, a wider geographical distribution, and a greater agricultural impact than t...

Ten cultivars and 13 germplasms of white clover (Trifolium repens) were evaluated in the greenhouse for resistance to the southern root-knot nematode, Meloidogyne incognita race 4. One hundred plants of each cultivar or germplasm were rated for percentage of the root system galled (PRSG) at 60 days after inoculation with root-knot nematode eggs. Tillman (9%) and SRVR (19%) had the highest perce...