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The current and pending restriction on the use of soil fumigants and other nematicides effective in controlling nematodes in field grown floriculture crops has increased the importance of determining the relative susceptibility of these crops to important species of root-knot nematodes. Greenhouse experiments were performed to assess the susceptibility of several floriculture crops grown in Florida to the three most common species of root-knot nematode, Meloidogyne arenaria, M. incognita, and M. javanica. Root growth and health, as well as nematode galling and egg production were evaluated for Celosia argentea (cockscomb), Delphinium elatum (larkspur), Antirrhinum latifolium (snapdragon), and Helianthus annuus (sunflower). A susceptible host, Solanum lycopersicum ('Rutgers', tomato), was included in all trials for comparison. Most of the floral crops tested were highly susceptible to all three species of rootknot nematodes. Delphinium was not tested for susceptibility to M. arenaria but was consistently less susceptible to M. incognita and M. javanica than the other floral crops tested with those nematode species. Results of these greenhouse trials are consistent with observations from field trials on alternative fumigants conducted in Florida in which low levels of galling by rootknot nematodes were consistently observed on Delphinium. [ABSTRACT FROM AUTHOR]

Two open pollinated commercial pecan seedling rootstocks were evaluated for resistance to Meloidogyne partityla in field microplots. Rootstocks tested included seedlings derived from open pollinated seed of 'Curtis' and 'Elliott' parent trees. 'Elliott', a susceptible pecan seedling rootstock for M. partityla, also served as the identifiable control. Both commercial pecan rootstocks supported nematode reproduction as indicated by number of egg masses per plant, number of eggs per plant, and number of eggs per gram dry root and were not significantly different between rootstocks 30 months after inoculation. Differences in tree growth, as measured by trunk diameter and dry root weight, were not found between 'Elliott' and 'Curtis' rootstocks, but growth suppression of both stocks was influenced in the presence of M. partityla. These results provide useful insights into M. partityla being a potentially economically important pathogen to the pecan industry in the southeastern United States and that the search for an IPM strategy for control of M. partityla on pecan is warranted. [ABSTRACT FROM AUTHOR]