Reproduction and inter-breeding within and between populations of Xiphinema diversicaudatum (Nematoda: Dorylaimoidea)
AbstractReproduction by individual female Xiphinema diversicaudatum from eleven populations and by females which developed from the progeny of these original females was examined in a laboratory study. Unmated females did not produce progeny thus reproduction by X. diversicaudatum is unlikely to be thelytokus. Females from all populations produced progeny when mated and numbers of progeny produced by individual females differed. Similarly, mean numbers of progeny produced by females from the populations varied significantly (P<O.OOl) in the first and the second generations of progeny. Females from nine of the populations when inter-bred with males from a Scottish population produced reproductively viable progeny. Few females from a Spanish population produced progeny when mated with Spanish or Scottish males and the use of three species of host plants little affected reproduction by these nematodes. It is concluded that despite morphometric differences the anatomical similarity and successful inter-breeding between populations is evidence that probably they all belong to one classical biological species, X. diversicaudatum.