Assistance and training on banana pests evaluation : SBBS technical assistance report

The burrowing nematode, Radopholus similis and the black weevil borer, Cosmopolites sordidus are major pests of banana and may become a limiting factor of production. Both are present in Surinam. Pesticides available against these two pests cause many problems of safety. Against R. similis, alternative control is based on adaptation of agricultural practice: after destruction of infested banana plantations, flooding and fallow may destroy the nematodes; by planting with nematode free plants (vitro-plants) it may be possible to grow bananas several years without this pest. We verified the efficiency of this technique, which looks successful in Nickerie. In Jarikaba, some banana volunteers have survived during flooding and fallow period, so that limited population have survived. Efficiency of this system of control needs also regular assesment of nematodes population, in fields as in greenhouses. For this reason, SBBS technicians have been formed to sampling, extraction and recognition of phytoparasite nematodes according to standardized procedures. If population of C. sordidus are low in Nickerie, they reach relatively high levels in some plots of Jerikaba. An insecticide application is needed quickly. For the future, alternative biological control methods may be developed; they are based on pheromone trapping, using either mass trapping (monitoring, or in case of low infestation) either traps contaminated with entomopatogenic nematodes (high weevil infestation). These methods need also monitoring and biocontrol efficiency assesment. Technicians have been trained for this purpose according to standardized protocole. Recommendations are also exposed to improve these methods (i.e. elimination by herbicide injection of surviving banana volunteers plants after flooding, filtration of irrigation water to prevent nematodes contamination of vitro-plants in greenhouses...). (Résumé d'auteur