Assessing the potential threat of Chilo sacchariphagus (Lepidoptera: Crambidae) as a pest in South and Swaziland

• Published in: African entomology Vol. 16; no. 1
• Main Authors: Bezuidenhout C.N, Goebel R, Hull P.J, Schulze R.E, Maharaj M
• Format: Journal Article
• Language: English
• Published: 2008
• Subjects: AFRIQUE DU SUD; CARTOGRAPHIE; CHILO SACCHARIPHAGUS; EPIDEMIOLOGIE; FACTEUR CLIMATIQUE; REUNION; SACCHARUM; SURVEILLANCE EPIDEMIOLOGIQUE; SWAZILAND; TEMPERATURE

The spotted stem borer Chilo sacchariphagus (Lepidoptera: Crambidae) is a key pest of sugarcane. In the 19th century it was accidentally introduced into Réunion Island and Mauritius and more recently into Mozambique. The effect of temperature on development and reproduction of the borer have been thoroughly studied and well quantified. South Africa and Swaziland, two sugarcane producers neighbouring Mozambique, have some of the most comprehensive temperature data sets in Africa and the aim of this study was to use these data to generate maps depicting these countries' vulnerability, in terms of climate, to invasion by C. sacchariphagus. Three maps based on a mortality index, a maintenance index and a mating index, respectively, were generated for the region. For comparison, similar index values were generated for a site in Réunion where the borer is well established. The climatic potential for the pest in South Africa and Swaziland is below that of Réunion. The KwaZulu-Natal coastline of South Africa and adjacent deep river valleys, especially in the north, are the most vulnerable parts in the region. This study generated a method whereby other prevalent pests could also be assessed. (Résumé d'auteur)