Study of the interactions between endomycorrhizae and Radopholus similis populations with a difference in pathogenicity, in the roots of Musa spp

The interaction between the burrowing nematode Radopholus similis and the endomycorrhizal fungus Glomus sp. on banana was studied in a pot-experiment. Two different populations were used, an aggressive population originating form Ivory Coast (CIV) and a less aggressive population originating from Australia (AUS). No increase in plant growth was observed when mycorrhiza were inoculated. The number of nematodes per gram of roots inoculated with CIV was significantly higher than in roots inoculated with AUS. These results correspond to the aggressivity of the populations. Nematodes did not affect the mycorrhizal colonization. In a short term pot-experiment, the initial penetration of two R. similis populations with a different aggressivity was investigated after 24 hours and 48 hours. Again a population with a high aggressivity (Cameroon, CMR 12) and a less aggressive population were used. Because of a too low number of nematodes that penetrated the roots, no observation could be made. To have a better understanding in how mycorrhiza can have an influence on the penetration of nematodes in the roots of banana, more controlled conditions were developed. For the third experiment, excised roots placed in a Petri dish with sand were studied. This experimental setup made it possible to have a closer view on the initial penetration of the nematodes in the roots. Different treatments were performed and different experimental parameters were checked. This experimental setup seemed to have some shortcomings so it needs further development. (Résumé d'auteur