Establishment and recycling of Romanomermis culicivorax (Nematoda: Mermithidae) in Louisiana ricelands.

The postparasitic stage of Romanomermis culicivorax, applied at dosage rates of 0.025 and 0.05 g/m2, was able to establish, recycle and overwinter in a riceland habit in southern Louisiana. Percent parasitism ranged from 0 to 54.1% during the 22-month study. Parasitism of Psorophora columbiae larvae was significantly greater (P less than 0.05) along levee ditches than in the central portions of the fallow riceland plots on 3 of 4 sampling dates in 1983. As percent parasitism increased within the population of Ps. columbiae located in bioassay containers, the degree of superparasitism also increased.