| Molecular identification for 7 burrowing nematode (Radopholus similis) populations collected from different regions, was carried out, and the ITS regions of rDNA were sequenced and analyzed. Indoor bioassay of six nematicides on the nematode were conducted.Reproductions of the burrowing nematode (Radopholus similis) on carrot disks, the effects of inoculation time, inoculation density, and one-female inoculation on its reproduction, were tested. The results showed that the carrot disks inoculated with Radopholus similis obtained the maximum reproduction after sixty days, the maximum reproduction also obtained with inoculation of twenty-five nematodes, and the nematode may have parthenogenesis.With Ferris et al.(1993) primers, a 706bp DNA fragment was obtained by PCR amplified from 7 Radopholus similis populations. The results of cloning and sequencing the ITS regions, sequence and homology analysis revealed that they shared high homology (99.09%) with the known sequence.Based on the sequence characteristics of rDNA-ITS region of Radopholus similis, RsF1/RsR1, a pair of Primers, was developed to identify the nematode. The specific amplified product with RsF1/RsR1 primers was 271 bp. With the D3A/D3B , a method for rapid molecular diagnosis of Radopholus similis based on duplex PCR with species specific primer was described. The results showed that the method was both accurate and effective in quick detection of the nematode.As its severe economical damage to banana all over the world and one of the first grade plant quarantine nematode pest in China, it's very important to control Radopholus similis. The results of the indoor bioassay of six insecticides on Radopholus similis showed that, azadirachtin (EC) and Avermectin (EC) are two recommendable bio-pesticides, the chemical pesticide matrine should not be recommended due to its little effects on the nematode and possible environmental pollution. But the results of the indoor bioassay must be tested by field experiments.
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