The Identification And Pathogenicity Testing Of Meloidogyne Species On Sycamore In Qingdao

The investigations of root-knot nematode disease of sycamore in Qingdao and its circumjacent cities were conducted. Among 15 collected Meloidogyne populations, two Meloidogyne species were identified as Meloidogyne paraplatani(a new species found by Zhao, 1999, unpublished) and M. arenaria (Neal, 1889)Chitwood, 1949.By means of morphological study, M. paraplatani differed from its related species - M. platani Hirschmann, 1981 and M. arenaria in perineal pattern of female, size, and morphology of male stylet. rDNA-ITS-RFLP analysis showed that rDNA-ITS of M. paraplatani couldn't be zymohydrolyzed by testriction incision enzyme Haeâ…¢, which differed from M. arenaria. Host testing indicated that M. paraplatani could form a few galls on tobacco without egg mass-forming, and it could not form galls or egg masses on tomato and watermelon, which differed from P. platani. In preliminary host range testing between 20 ornamental plants, M. paraplatani formed galls only on Zantedeschia aethiopica (Linn.) Spreng.The morphological study showed that the population of M. arenaria had the characteristics of the species in perineal pattern of female and morphology of stylet base of male. The esterase (EST) phenotype analysis indicated that the population of M. arenaria presented A2 EST phenotype.With limited geographical distribution, narrow host range and bad adaptability, M. paraplatani had lower risk to agriculture and forestry, but was of great importance in plant quarantine. With wide host range, extensive geographical distribution and good adaptability, M. arenaria had high risk to agriculture and forestry, and was of great quarantine importance.