Publications des agents du Cirad


Survival of Radopholus similis (Cobb) in volcanic soils without host-plant

Chabrier C., Carles C., Mauriol-Bastol C., Quénéhervé P.. 2008. In : 5th International Congress of Nematology. Book of proceedings, July 13-18, 2008, Brisbane, Australia. s.l. : s.n., p. 200-200. International Congress of Nematology. 5, 2008-07-13/2008-07-18, Brisbane (Australie).

The burrowing nematode Radopholus similis is the most damaging nematode on bananas. To minimize applications of nematicide, cropping systems based on fallow, rotation crop, and clean planting material have been developed in the French West Indies. Here, we study soil survival of R. similis to optimize the benefit of the intercropping period and to increase the economical durability ofbanana cropping systems. We monitored for six months in the laboratory the survival of calibrated populations of R. similis on nitisol and andosol, two soils derived from volcanic ashes and pumices. We studied different water potentials ranging from 0 to -700 kPa, on soil previously treated by frost or undisturbed. Mortality of adult R. similis follows a sigmoid decrease. In soils previously treated by frost, R. similis survive better in wet soils (-0,1 kPa) than in dry soils (-100 to -700 kPa). At the opposite, on undisturbed soils, R. similis survived better in dry soils. Half lives were two weeks inferior (from 27 to 37 days) for juveniles R. similis compared to adult females. Males survived from 40 to 71 days, significantly longer than females; one possible explanation is that males' energy is totally directed towards the reproduction and not for food foraging (males doesn't feed as they exhibit no fimctional stylet and digestive tractus). These results are consistent with the absence of anhydrobiosis strategy in R. similis compared to Pratylenchus coffeae. These results also suggest that R. similis survival depends not only of environmental conditions such as soil moisture and microbial activity, but also of their behaviour. (Texte intégral)

Documents associés

Communication de congrès

Agents Cirad, auteurs de cette publication :