RESUMEN
The fall armyworm moth, Spodoptera frugiperda, is a migratory species composed of sympatric corn and rice strains. The strains are indistinguishable in morphology but can be recognized by molecular markers. We have cloned and characterized seven monomer units of a repeated DNA sequence, called FR, which is found exclusively in the genome of the rice strain individuals. The 189 bp FR units are tandemly organized in arrays longer than 30 kb. Female individuals possess over 100-fold more of the FR sequence than male individuals. The repeated sequence is not methylated at GGCC sites, and shows high sequence similarity among repeat units.
Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Spodoptera/genética , Animales , Secuencia de Bases , Clonación Molecular , ADN/química , ADN/genética , Femenino , Genoma , Masculino , Metilación , Repeticiones de Minisatélite , Datos de Secuencia Molecular , Oryza , Especificidad de la Especie , Zea maysRESUMEN
The cuticular lipid composition of lower and upper leaves of five genotypes of field-grown corn,Zea mays L., was determined by combined gas chromatography-mass spectrometry. Surface lipids of the upper leaves had a higher proportion ofn-alkanes (45-52%) than the lower leaves, while the lower leaves had higher percentages of fatty alcohols (12-18%) than the upper leaves. Scanning electron microscopy showed that the upper leaves of two corn genotypes, MpSWCB-4 and Cacahuacintle X's, had a smooth amorphous appearance, while the lower leaves had a dense array of wax crystals.Spodoptera frugiperda (J.E. Smith) larvae weighed more and developed more rapidly when they were reared on diet containing corn foliage from which the cuticular lipids had been removed than when they were fed untreated foliage. However, growth was not inhibited when larvae were fed diet containing the cuticular lipid extracts or individual cuticular lipid components.