Color polymorphism and allele frequency in a Brazilian population of the sunflower caterpillar Chlosyne lacinia saundersi (Doubleday) (Lepidoptera: Nymphalidae)

Abstract

Neotropical Entomology 32(1): 159-161 (2003) Polimorfismo de Coloração e Freqüência de Alelos em uma População Brasileira de Lagarta-do-GirassolChlosyne lacinia saundersi (Doubleday) (Lepidoptera: Nymphalidae) RESUMO ) para estimar com precisão o tamanho ideal da amostra. A partir de 800 espécimes de quarto e quinto ínstares, as freqüências estabilizaram. As freqüências gênicas foram calculadas com base na freqüência de cada fenótipo. O alelo R do locus rufa ocorreu na freqüência de 7% e o alelo r teve freqüência de 93 %. O alelo B do locus bicolor teve freqüência de 31,8% e o alelo b teve freqüência em torno de 62,2%. PALAVRAS-CHAVE: Epistasia, genética de populações, genética ecológica, fenótipo ABSTRACT -The aim of this work was at calculating allele frequency color polymorphism in a population of sunflower caterpillar, Chlosyne lacinia saundersi (Doubleday) from Londrina, Paraná State, Brazil. Allele frequency in insect populations can be used as genetic marker to compare populations from different geographical and host origins. There are three phenotypes conditioned by two loci interacting epistatically. The phenotypes are: rufa (oranged colored larvae), bicolor (black larvae with dorsal orange stripes) and nigra, larvae with the body entirely black, sometimes with dorsal yellow dots, best seen in the fourth and fifth instars. Samples were taken independently in an attempt to obtain all combinations of crossing among genotypes. The genetic mechanism of this polymorphism is well known. A Chi-Square test (χ 2 ) was used to estimate the ideal sample size. The frequencies stabilized, with over 800 fourth and fifth instars larvae even with increased sample size. The allele frequencies were calculated based on the frequency of each phenotype. The allele R of rufa locus had a frequency near 7.0% and the allele r near 93.0%, the allele B (bicolor) had a frequency around 31.8% and allele b frequency near 68.2%.

Plant Metabolites Involved in the Differential Development of a Heliantheae-Specialist Insect

“…The larval stage has five instars, and the complete insect life cycle usually takes 30-40 days [18]. Butterfly wings are usually black with yellow-orange spots, and most of the caterpillars are black with orange stripes and black spines; however, color polymorphism has been described for both, adults and larvae [19][20][21]. In the field, Brazilian populations of C. lacinia commonly infest Tithonia diversifolia (Hemsl.)…”

Natural Products Diversity in Plant-Insect Interaction between Tithonia diversifolia (Asteraceae) and Chlosyne lacinia (Nymphalidae)

“…Butterfly wings are mainly black with yellow-orange spots of varying sizes [18,19,20]. Its larvae pass through five instars and they are usually black with dorsal orange stripes, however color polymorphism is significant within populations [21,22]. In Brazil, T. diversifolia leaves herbivory by C. lacinia mainly occurs from April to June (autumn) [23].…”