Researchers discover new stem borer controls
African and UK scientists have made a breakthrough in the development of novel and ecologically benign approaches to controlling maize spotted stem borers ( Chilo partellus) on maize as an alternative to the use of pesticides. Kenya-based International Centre of Insect Physiology and Ecology, the ICIPE (Nairobi), and the UK Rothamsted Research (Harpenden, Hertfordshire), discovered that certain maize landraces obtained from South America have sophisticated defence strategies against insect pests. These maize plants produce herbivore-induced plant volatile chemicals that attract parasitoid wasps as soon as the stem borer moths lay their eggs. This trait has been lost, possibly through conventional breeding, they say. The parasitoid wasps kill the stem borer eggs and caterpillars. The researchers envisage the findings being developed to substitute for pesticide use, particularly for small-holder farmers in eastern Africa.