A simple PCR-RFLP method to distinguish between species and strains of Microctonus parasitoids found in New Zealand

Abstract

Two strains of the hymenopteran parasitoid Microctonus aethiopoides have been released in New Zealand for the biological control of Sitona weevil species. One attacks Sitona discoideus, a pest of lucerne, and the other attacks Sitona lepidus, a pest of clover. Two other Microctonus species also attack weevils in pasture; M. hyperodae was released for the biological control of Listronotus bonariensis and the native M. zealandicus attacks Irenimus spp. These Microctonus species can attack non-target weevil hosts and the identification of the larvae of the different Microctonus species and the separation of adults of M. aethiopoides strains can only be achieved by molecular methods. This paper describes a simple polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) method for distinguishing between the two M. aethiopoides strains, M. hyperodae and M. zealandicus. This PCR-RFLP method requires minimal molecular equipment and is cheaper and/or faster than other molecular methods. © 2012 New Zealand Plant Protection Society (Inc.).