Biology of the Most Widely Distributed Sugarcane Stem Borers, Diatraea spp. (Lepidoptera: Crambidae), in Colombia

Most studies on insect biology and ecology of sugarcane borers have focused on Diatraea saccharalis (Fabricius), the most widely distributed species in the Americas. Little information is available on the biology of other borer species present in Colombia, such as D. indigenella Dyar & Heinrich, D. busckella Dyar & heinrich, and D. tabernella Dyar, that present greater expansion and damage in sugarcane-growing regions. The biology of all four species was accordingly studied under laboratory conditions. Diatraea saccharalis presented the shortest development time (39.4 days) and D. busckella the longest (58.2 days). Immature survival was higher for D. saccharalis (83%) and D. tabernella (77%), with the latter also presenting the highest pupal weight (256.6 mg). Observations on reproduction indicate that D. tabernella develops a larger number of egg masses per female (67.3) as compared with D. saccharalis (28.7). All three species spent more time in the pupal stage and resulted in greater pupal size than D. saccharalis; in particular, D. indigenella showed longer female longevity than D. saccharalis. High immature survival rate and greater reproductive success in D. tabernella could potentially generate a larger population in the field, whereas D. busckella takes longer to complete its development, thus increasing the chances of causing greater injury to sugarcane plants. Discussion on biology, ecology, and pest management of these little-known species is done using as model the better-known D. saccharalis.