The effects of leaf toughness on the feeding activities phytophagous insects have been discussed by many workers, but only a few have undertaken quantitative measurements of this parameter. Rao and Venkatraman (1941), Rao (1947) and Khanna et al. (1947), all studying top-borer infestations in sugar-cane, measured a variety anatomical features such as degree of lignification, and thickness of cell walls in stem sections, and attempted correlate such toughness indices with the incidence of pest attack. Williams (1954) working on the Acrididae, followed by Tanton (1962) on the mustard beetle, Phaedon cochleariae F., attempted direct measurements of toughness using a simple penetrometer. In this device, an entomological pin with a light card reservoir mounted on top of it was forced through a piece of taut leaf by adding dry sand to the reservoir. The weight of sand required cause penetration of the leaf was then used as an index of toughness.
Document Type: Research Article
Publication date: December 16, 1968
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.