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The burrowing nematode, Radopholus similis, is the most important nematode pest of banana and plantain worldwide, causing severe yield losses in commercial and local consumption cultivars. Chemical control is currently the most-used method to manage the nematodes, although nematicides are dangerous, toxic and expensive. Therefore, nematode control through genetic improvement is widely encouraged. Protocols have been set up to detect sources of resistance in the existing Musa germplasm, but the screening under greenhouse and field conditions is laborious and time consuming. In vitro screening could facilitate this process by picking up sources of resistance at an early phase. In this study, a procedure for in vitro screening for the resistance to R. similis was set up by determining the optimal incubation time and the optimal nematode inoculum. In a second step, the optimized procedure was confirmed by screening a selection of Musa varieties with a known host plant response. Except for ‘Yangambi Km5’, their host response under in vitro conditions corresponded to their host response under greenhouse or field conditions. The susceptible status of ‘Grande Naine’, ‘Gros Michel’ and ‘Cachaco’ was confirmed, as well as the resistant status of ‘Pisang Jari Buaya’ and ‘SH-3142’. [Copyright &y& Elsevier]

Focuses on a study which investigated the host plant response of Eumusa and Australimusa bananas to migratory endoparasitic and root-knot nematodes. Materials and methods; Resistance of bananas to Radopholus similis; Host plant response to Pratylenchus coffeae.

The reproductive fitness of three Pratylenchus coffeae populations (Honduras, Ghana and Vietnam) and three Radopholus similis populations (Costa Rica, Cuba and Ghana) on carrot disks was studied as a function of time and inoculum densities. In the first study, the reproductive fitness of the isolates was followed during 11 weeks for P. coffeae and during 7 weeks for R. similis. All the populations increased with time. No distinction could be found in the maximum growth rate of the Pratylenchus populations. The R. similis population from Cuba had a higher maximum growth rate than those from Ghana and Costa Rica. All the Radopholus populations showed a faster multiplication than P. coffeae. In the second study, the influence of the inoculum density on the reproductive fitness was determined for the six populations. The differences in reproduction ratios confirmed the results of the first study. Effetde la duree et du taux d'inoculum sur la reproduction de trois populations de Pratylenchus coffeae et de Radopholus similis eleves sur rondelles de carottes - La reproduction de trois populations de Pratylenchus coffeae (Honduras, Ghana et Vietnam) et de trois populations de Radopholus similis (Costa Rica, Cuba et Ghana) a ete etudiee en elevages sur rondelles de carottes. Dans une premiere etude, la multiplication du P. coffeae a ete etudiee pendant 11 semaines et celle du R. similis pendant 7 semaines. Toutes les populations se sont accrues avec le temps. Aucune difference dans la vitesse de croissance maximale n'a ete observee entre les differentes populations de Pratylenchus. La population de R. similis provenant de Cuba a montre une vitesse de croissance plus elevee par rapport aux autres populations. Tous les isolats du R. similis ont montre une multiplication plus rapide que celle des isolats du P. coffeae. Dans la deuxieme etude, l'effet du taux d'inoculum sur la reproduction a ete determine. Les differences dans les taux de reproduction observees ont confirme les resultats obtenus dans la premiere etude. [ABSTRACT FROM AUTHOR]