This study was done to determine the species of plant parasitic nematodes that attacked strawberries in the Bursa region (Northwestern Anatolia) of Turkey from 1998 to 2000. Soil and plant samples were harvested from approximately 5% of the strawberry fields in this region. Species of plant parasitic nematodes and population densities were determined in these samples. Fourteen species belonging to the family Aphelenchoididae order Aphelenchida and 13 species belonging to several families within the order Tylenchida were identified. The rate of occurrence of the different species and the researchers who originally described those species in Turkey are also reported. Jpn. J. Nematol. 34(2), 73-78 (2004).

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We have cloned and sequenced a gene encoding a novel crystal (Cry) protein, Cry21Ba1, from Bacillus thuringiensis serovar roskildiensis. The gene, cry21Ba1, was amplified by polymerase chain reaction using template (alkaline-cell lysate or plasmid DNA fraction of the Bacillus) and primers (pairs of oligomeric DNAs designed from the conserved amino-acid sequence blocks of Cry5-Cryl2-Cryl3-Cryl4-Cry2l-type Cry proteins), and was cloned followed by sequencing. The gene, cry21Ba1, should be functional, because it has putative promoter sequences upstream of the initiation codon and an inverted repeat downstream of the stop codon. The open reading frame (ORF) of cry21Ba1 is a 3, 858-bp DNA encoding Cry21Ba1 consisting of 1, 286 amino acids. The nucleotide sequence of the cry21Ba1 ORF is 75% identical with that of the cry2lAa1 (the gene for a known nematode-toxic Cry protein, Cry21Aa1) ORF. The amino acid sequence of Cry21Ba1 is 67% identical with that of Cry2lAal. High amino-acid-sequence similarity between these Cry proteins indicates that Cry21Ba1 is putatively nematode-toxic. Jpn. J. Nematol. 34 (2), 79-88 (2004).

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Soil nematode densities and family-level faunal compositions were investigated for five months after chloropicrin fumigation in soybean fields in Japan. Our objective was to examine whether diversity measurements and ecological indices can describe appropriately structural changes in nematode communities after chemical disturbance. The total nematode density in the fumigated plots drastically decreased just after chloropicrin treatment, but gradually recovered. After the chemical treatment, the dominant nematode taxon changed from Rhabditidae to Cephalobidae; the fungivorous nematode guild and guilds with cp value 3-5 (CP35, K-strategists) were hardly detected. In the non-fumigated control plots Rhabditidae still predominated, and the fungivorous guild and CP35 guilds increased. Among the diversity indices and the ecological indices examined, Shannon- Wiener's H', Maturity Index (MI), Maturity Index without opportunistic bacterivorous guilds (MI (2-5)), Enrichment Index (EI) and Structure Index (SI) described these structural changes in the nematode communities. The Channel Index failed to detect significant effect of fumigation on decomposition pathways because both the fungivorous nematode guild and Rhabditidae were reduced in the fumigated plots. Replacement of Rhabditidae with Cephalobidae in the plots required careful interpretation of MI and EI behaviors. Even under such a replacement, MI (2-5) and SI were still useful in evaluating appropriately the ecological status of nematode communities after chemical disturbances. Jpn. J. Nematol. 34 (2), 89-98 (2004).

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[in Japanese]

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