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The effect of the presence of organic amendment on the activity of two selected strains of Pochonia chlamydosporia var. catenulata (Kamyschko ex Barron and Onions) Zare & Gams on Meloidogyne enterolobii Yang & Eisenback was evaluated. The fungal strains studied were IMID SD 187 from Cuba and CG1006 from Brazil. The experiment was carried out in Embrapa-Cenargen, Brasilia-DF (Brazil), under greenhouse conditions during February-April, 2011. An agricultural soil (sterilized and not sterilized) was used and combined with the presence-absence of organic amendment (Bioplant) (1:1 v/v). Four treatments were prepared inoculating polyethylene bags with 4kg of substrate with 5000 chlamydopores.g-1 of substrate of each of the strains, leaving non-inoculated bags as controls. Then, a chicory plant was transplanted into each bag, and 5000 juveniles/eggs of M. enterolobii were added. Colonization of both strains of P. chlamydosporia var. catenulata was in the order of 103-104 UFC,g-1 in the soil and roots. The percentages of egg mass colonization and egg parasitism of the strain CG1006 were higher, between 77-92% and 71-78%, than those of IMI SD 187, which were 58-89% and 37-74%, respectively. Although the galling index of M. enterolobii was not reduced by the effect of none of the fungi, the number of healthy egg was reduced compared with the control. The results indicated that the presence of organic amendment did not influence the activity of the native strain significantly, but it did influence that of the foreign strain (IMI SD 187), fundamentally in natural soil. Therefore, the pertinence of studies in non- sterilized soils was ratified for offering more reliable information for the selection of promising strains as biological control agents of nematodes and their use within nematode management strategies. [ABSTRACT FROM AUTHOR]

Recently, Pochonia chlamydosporia (Goddard) Zare y Gams was isolated from parasitized eggs of Meloidogyne enterolobii Yang y Eisenback (syn. jun. Meloidogyne mayaguensis Rammah y Hirschmann) in guava (Psidium guajava L.) plantations, at the northeast of Brazil. Due to the potential danger of this pest for a large group of crops, including vegetable crops, a greenhouse experiment was conducted with two repetitions in time. The aim was to evaluate the saprophytic and parasitic activities of three brazilian strains (CG1003, CG1006 and CG1041) and the cuban strain (IMI SD 187) of P. chlamydosporia against M. enterolobii in a tomato (Solanum lycopersicum L.)- lettuce (Lactuca sativa L.) crop sequence. At the end of the cultivation, 6 month after the application, colonization of P. chlamydosporia was in the order of 104 CFU.g-1 of soil and 103 CFU.g-1 of root, with exception of the strain CG1041 (102 CFU.g-1 of root). Egg mass percentage was higher than 60% in all treatments, while parasitized egg percentage was between 45-55%. These results validated the cuban strain against a nematode target under different conditions from those it originally came from; the brazilian strain potential as biocontroler of M. enterolobii was also demonstred. Future investigation perspectives with those fungi are opened for their use as biological control agents for nematode pest management strategies. [ABSTRACT FROM AUTHOR]