Rates of Spore Transmission, Mortality, and Production for the Nematophagous FungusHirsutella rhossiliensis

Augmentation of Soil with the Nematophagous FungiHirsutella rhossiliensisandArthrobotrys haptotyla

“…To obtain larger numbers of parasitized nematodes than could be transferred from CMA/4 cultures, sand cultures in petri dishes (10 cm in diameter, 8 cm high) were prepared as described previously (10,24), except that the sand was moistened with potato dextrose broth instead of V8-juice broth. In this method, large numbers of healthy nematodes are added to fungus-colonized sand and recovered after sufficient time for infection and colonization.…”

“…To add the nematophagous fungus Hirsutella rhossiliensis to soil (and thereby attempt to achieve short-term biological control of plant-parasitic nematodes), researchers have sometimes used fungus-parasitized nematodes as inoculum (10,24). Selection of this inoculum form was justified as follows.…”

“…Third, fungus-parasitized nematodes serve as foci for sporulation (i.e., for in situ production of conidia). Finally, addition of parasitized nematodes to soil has caused significant proportions of healthy nematodes to become parasitized (10,24).…”

“…rhossiliensis-parasitized nematodes can be produced in the laboratory (10,24), but obtaining and storing the large number of parasitized nematodes necessary for treating an agricultural field is impractical. Because the fungus-parasitized nematode seems to consist of assimilative hyphae contained in host cuticle, Lackey et al (17) focused on assimilative hyphae in their development of a substitute inoculum form.…”

The living strategy of nematophagous fungi

“…The fungi H. minnesotensis and H. rhossiliensis are important parasites of second-stage juveniles (J2) of the soybean cyst nematode (Heterodera glycines) and have shown great potential as biocontrol agents of this and other plant-parasitic nematodes. Parasitism of nematodes by H. rhossiliensis in the fi eld is dependent on several factors such as conidia density, the distance that the host nematode moves, soil moisture, and the size of soil particles (Jaffee et al 1990;Timper et al 1991;Tedford et al 1992). The distance traveled by nematodes determined their chance of encountering natural enemies, and the movement of water in soil may disseminate fungal spores (Chen and Dickson 2004).…”