Identification of Heterodera schachtii group species in Italy by morphometrics and RAPD-PCR

Abstract

Nine Italian populations of the Heterodera schachtii group, including H. schachtii, H. trifolii from carnation, H. trifolii from sugarbeet and H. daverN, were compared using both morphometrical and RAPDPCR techniques. H. trifolii f. sp. beta differed markedly from the other populations because of its greater cyst and juvenile dimensions. The size of the tail is statistically the only highly significant morphometric character valid to separate one H. schachtii from another, H. trifolii from carnation, H. trifolii from sugarbeet and H. dallerti. Cluster analysis of morphometric characters of cyst cones and juveniles distinguish H. trifolii associated with sugarbeet from the remaining cyst-forming populations. The dendrogram constructed with molecular data separates H. schachtii populations from the H. tr[folii complex members.