We evaluated the efficacy of adsorption substrates, dried plant chips, and leaf surface application of Bidens pilosa var. radiata aqueous extract and plant tissues on Meloidogyne incognita. Soil mixed with 5 g of perlite loaded with a stock solution of B. pilosa var. radiata extract and treatment with dried plant chips (10– 60 g; 2.5 kg soil in 1/5,000 of a Wagner pot) mixed with soil significantly reduced root-knot formation as well as the population density of second stage M. incognita juveniles. In addition, planting–hole treatment with 3 and 5 g of perlite loaded with a stock solution suppressed root-knot formation compared to 1 g of perlite diluted to 0.1×. In contrast, application of B. pilosa var. radiata extracts to leaf surfaces did not control M. incognita. Thus, planting–hole and total soil mixing treatments of the substrate using B. pilosa var. radiata extracts and dried plant chips mixed with soil aid in controlling the proliferation of M. incognita.

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A rapid and highly sensitive assay method to evaluate the infectivity of Meloidogyne incognita second-stage juveniles (J2s) is reported. Among the substrates to grow a seedling in a plant culture tube, nursery soils composed of small granular soil particles were the best both in root growth and ease of substrate removal from the root. As a host plant, balsam and cucumber were considered the most appropriate host plants for the assay in the test tube among the 6 plant species. Twenty J2s individuals were inoculated onto a 1-week-old balsam or cucumber seedling in a culture tube containing granular nursery soil, and nematodes in the root system were stained by the acid fuchsin method 1 week after inoculation. The number of infected nematodes increased and then plateaued at seven days after inoculation in both types of seedlings. To demonstrate the efficiency of this method, 1-week-old balsam seedlings were infected with fosthiazate-treated J2s in the presence of fosthiazate and dosedependent infective suppression was observed in the treated J2s. This method enables us to use a small number of nematodes as an inoculum for infection assays and to complete the assay within two weeks from the sowing of seeds.

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Reproduction of Meloidogyne incognita, Meloidogyne arenaria, Pratylenchus coffeae, and Pratylenchus penetrans on two Neotyphodium uncinatum-infected Italian ryegrasses, Bishamon and JFIR-18, was examined. All tested samples of Bishamon and JFIR-18 were individually checked to confirm infection with an endophytic fungus at the end of each experiment. There was no significant difference in host suitability between endophyte-infected and endophyte-free individuals of the two cultivars for any of the tested nematodes.

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Subanguina moxae has a scattered distribution in very limited areas in Japan. To know whether or not there exist any nucleotide sequence differences among the S. moxae collected from the different sampling places, the sequences of the ITS1-5.8SrDNA-ITS2 region of rDNA for 7 Japanese isolates (Tsukuba, Otsuki, Azumi, Shimashima, Azusagawa, Yuza and Fujikawa) were investigated. The sequence identity among the 7 Japanese isolates was over 99.7% (672 ～674/674bp) and that among Tsukuba, Yuza and Fujikawa isolates was 100%. The sequence identity between the 7 Japanese isolates and Russian Primorsky Territory isolate (Genbank, AF396314) was 99.7~100% (672～674/674bp) and that between the 7 Japanese isolates and China Yunnan Province isolate (JN865234) was 99.1~ 99.4% (668～670/674bp). Rather large nucleotide sequence differences in rDNA, such as those found between Japanese and China isolates, were not found among the 7 Japanese isolates .

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