Article

Biology of Sitotroga cerealella (Oliv.) (Lepidoptera: Gelechiidae) reared on five corn (maize) genotypes

Department of Entomology, ESALQ/USP, 13418-900 Piracicaba, Sao Paulo Brazil; Department of Zoology, Institute of Biology, UNICAMP, 13084-100 Campinas, Sao Paulo, Brazil
Journal of Stored Products Research (Impact Factor: 1.35). 01/1995; DOI: 10.1016/0022-474X(94)00044-T

ABSTRACT Laboratory experiments under controlled conditions of 30 ± 1 °C, 60 ± 10% r.h. and 14 h photophase were performed to study the biology of Sitotroga cerealella (Oliv.) reared on five natural diets of different corn (maize) genotypes. S. cerealella reared on the shrunken2 genotype displayed the longest developmental time (43.5 d) and the lowest fecundity (85.2 eggs/female). Although the egg to adult developmental time (40.2 d) of S. cerealella reared on sugary-opaco2 did not differ significantly from those on normal, opaco2 and sugary, the survival of the pre-imaginal stage (42.2%) was significantly reduced on this genotype. Significant differences were not found between the number of eggs hatched from females reared on these genotypes. The egg hatch ranged from 86.8 to 95.3% for the shrunken2 and opaco2 genotypes, respectively. Further rearing studies to determine the effects of these genotypes on the biology of S. cerealella are needed, since significant differences were not observed in the data from two successive generations.

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