Reproduction of Meloidogyne hapla and M. javanica was compared on Agrobacterium rhizogenes-transformed roots from several plants under monoxenic conditions. Meloidogyne hapla normally matured and laid eggs on transformed roots of tomato plants that were susceptible (Lycopersicon esculentum MILL. cv. Farstmore) or resistant (cv. Momotaro) to the nematode. Meloidogyne javanica normally matured and laid eggs on tomato (L. esculentum MILL. cv. Fastmore) and eggplant (Solanum melongena L.), but not on resistant tomato plants. The developmental zero degrees were 6.8°C for M. hapla and 10.1°C for M. javanica. The day-degrees for the onset of oviposition and for the completion of one generation after inoculation with 2nd-stage juveniles were 435 and 692 for M. hapla, and 378 and 566 for M. javanica, respectively. A slight negative temperature-dependency was detected in body length, tail length and a-value of juveniles of M. hapla and M. javanica. Jpn. I Nematol. 23: 63-70 (1993).

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Field trials for control of Japanese pine sawyer (Monochamus alternatus) larvae infesting pine logs were conducted in 1987 with the entomopathogenic nematode, Steinernema carpocapsae (str. Mexican). Differences in spray volume and application timing and rate were investigated. The upper surface of horizontally placed logs was applied with 20 million infective juveniles/m² in a spray volume of 300, 600 or 1, 200 ml/m². The 600 ml/m² rate resulted in the highest larval mortality. Nematodes were applied on three different dates, March 17, 30 and April 17 with the highest mortality of Japanese pine sawyer larvae being recorded for the April 17 application. This is attributed to the ambient air temperatures being above 12°C during the treatment. At the April 17 application, rates of 6×10⁶ and 12×10⁶ nematodes/m² showed 69.2 and 72.2% mortality of larvae within the logs. Steinernema carpocapsae appears to be an effective alternative to the chemical insecticide, fenitrothion, for treatment of pine logs infested with the pine sawyer larvae. However, this nematodes can not prevent the spread of pine wilt disease and integrated approach for pine sawyer suppression will still be needed. Jpn. J. Nematol. 23: 71-78 (1993).

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The callus tissues of susceptible (Pinus parviflora) and resistant species of pine (P. taeda) were inoculated with each of two isolates of Bursaphelenchus xylophilus (pathogenic and nonpathogenic) and one isolate of B. mucronatus (nonpathogenic). Changes in the amount of malondialdehyde (MDA), as an index of lipid peroxidation, and that of exuded ion were measured. On the callus tissue of P. parviflora, the amount of MDA increased only when a pathogenic nematode was inoculated, whereas on the callus tissue of P. taeda, the amount increased with the infection of any of the three isolates irrespective of its pathogenicity. Thus the callus tissues of P. parviflora responded in accordance with the pathogenicity of nematodes while that of P. taeda did not. Ion exudation from the callus tissue of P. taeda paralleled the pathogenicity of nematode isolate, whilst that from P. parviflora calli as almost the same with each of three isolates. Populations of each nematode isolate grew well on both species of pine callus tissues. However, on the callus tissue of P. parviflora, the rate of population increase until day six was far greater in the pathogenic isolate than nonpathogenic ones. In contrast, the rate on the callus tissue of P. taeda was almost the same among three isolates. Jpn.J.Nematol. 23: 79-89 (1993).

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