Biology, ecology, and control of the sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Pyralidae)

Abstract

The present study, conducted 1n the Lower R1o Grande Valley of Texas during 1972-1975, Is concerned with various biological and ecological aspects of the sugarcane borer. Principal areas of Investigation Include egg and larval survival, larval movement, diapause, time and duration of adult spring emergence, natural enemies, seasonal abundance on various hosts and chemical control. The percent of sugarcane borers which survive from a known number of eggs decreases as the .density of eggs Increases. Larvae surviving the higher egg populations appear to do more damage than those from the less dense populations. The sugarcane borer overwinters as a full grown diapausing larva. Peak Incidence 1n larval diapause occurs in October and November 1n the Lower Rio Grande Valley of Texas. Peak spring emergence of adults occurs 1n late March. Photoperiod 1s apparently primarily responsible for triggering spring emergence although temperature appears to have a modifying Influence. The male to female ratio of emergent adults 1s ca. 2 to 1. The principal parasite attacking the sugarcane borer 1s the egg parasite Trlchoqrairma spp. Two braconld larval parasItes, Apanteles diatraea Mues. and Agathis spp. occur 1n extremely low numbers. The most abundant predator group of the aerial portion of the sugarcane plant 1s the Aranelda. Major ground Inhabiting predators Include staphlinids, aranids, dermapterans, formicids* and carabids. One or more stages of sugarcane borers infest a minimum of 12 species of Gramlneae In the Lower R1o Grande Valley of Texas. A classification of these Insect-plant Interactions 1s presented. Effective control of sugarcane borer larvae can be obtained with the 3 Insecticides presently registered for use on sugarcane In Texas. Several candidate Insecticides are effective and have the potential to become future control agents.