Biological control of sugar-cane pests in mauritius: A case study

Abstract

There are 43 identified insect pests of sugar-cane in Mauritius, of which several are important enough to warrant control measures. However, insecticides are not used for this purpose. All the insect pests of sugar-cane are controlled biologically. This includes traditional biological control using parasites or predators, as well as more recent biology-based methods like the use of resistant cane varieties, sex pheromones, etc. Mauritius has the distinction of being the first country on record to have successfully introduced a natural enemy, namely the Minah bird, specifically to combat a pest—the Red Locust, Nomadacris septemfasciata , in 1792. Very few of the insect pests in Mauritius are indigenous; most of them are exotic, having been accidentally introduced into the country, one way or the other. Some of the important ones include: spotted stem borer ( Chilo sacchariphagus ), armoured scale ( Aulacaspis tegalensis ), white grub ( Clemora smithi ), white grub ( Heteronychus licas ), soft scale ( Pulvinaria iceyi ), armyworm ( Leucania loreyi ) and pink borer ( Sesamia calamistis ). The introduction of various natural enemies from different parts of the world has been made over the years with different degrees of success. In all, there are presently a total of 102 species of parasites and predators controlling 43 species of sugar-cane insect pests. With sugar-cane spread out over most of the island and representing 90% of all cultivated land, close vigilance over the important pest populations, and swift counter measures as appropriate, is required. This task is being performed efficiently and successfully by the Mauritius Sugar Industry Research Institute.