MODE OF PARASITISM OF MELOIDOGYNE AND OTHER NEMATODE EGGS BY DACTYLELLA-OVIPARASITICA

  • 1 January 1979
    • journal article
    • research article
    • Vol. 11  (3) , 282-288
Abstract
Hyphae of D. oviparasitica proliferated rapidly through Meloidogyne egg masses, and appressoria formed when they contacted eggs. The fungus probably penetrated egg shells mechanically, although chitinase production detected in culture suggested that enzymatic penetration was also possible. In soil, D. oviparasitica invaded egg masses soon after they were deposited on the root surface and eventually parasitized most of the first eggs laid. Occasionally the fungus grew into Meloidogyne females, halting egg production prematurely. The fungus parasitized eggs in the gelatinous matrix or eggs freed from the matrix and placed on agar or in soil. Specificity in nematode egg parasitism was not displayed, for D. oviparasitica parasitized eggs of 4 Meloidogyne spp. [M. arenaria, M. hapla, M. incognita and M. javanica], Acrobeloides sp., Heterodera schachtii and Tylenchulus semipenetrans. In tests in a growth chamber, parasitism by D. oviparasitica suppressed galling on M. incognita-infected tomato plants.