Studies on the biology of the sugar-cane pest Saccharosydne saccharivora (Westw.) (Hom., Delphacidae)

Abstract

An account is given of laboratory studies and field observations in Jamaica and British Honduras on the host-plants, life-history and habits of Saccharosydne saccharivora (Westw.), a major pest of sugar-cane. The original host-plants of S. saccharivora are shown to be two species of grasses, Andropogon glomeratus and A. bicornis. The immature stages of S. saccharivora are described and illustrated; the five nymphal instars may most easily be distinguished by their increasing size, the differentiation of the wing buds and the increasing spinosity of the metathoracic tibia and tarsus. Daily records of individuals of S. saccharivora show the duration of the different stages on fertilised plant cane at c. 80°F to be as follows: egg, 15–19 days; instar 1, 6–7 days; instars 2, 3 and 4, each 4–5 days; instar 5, 6–7 days; adult male, about one week; adult female, up to four weeks. The complete life-cycle took 6½–7 weeks, but was slower on unfertilised ratoon cane. In describing the habits of S. saccharivora, particular attention is given to feeding (feeding probes reach the bundle sheath cells and phloem of the lamina), oviposition (young leaves are the preferred oviposition site) and migration (immigration of adults on to young cane occurred at all times of year).