Lepidoptera genitalia

About: Lepidoptera genitalia is a research topic. Over the lifetime, 10114 publications have been published within this topic receiving 78876 citations. The topic is also known as: Uncus.

Reproductive Isolation between Two Populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) Collected in Corn and Rice Fields from Central Colombia

Abstract: Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a Neotropical moth that has diverged into corn, Zea mays L., and rice, Oryza sativa L., host strains because these plants are their most frequently used hosts. The corn strain also has been found in cotton, Gossypium hirsutum L., and sorghum, Sorghum bicolor (L.) Moench, and the rice strain in small grasses and pasture grasses. Studies of the reproductive isolation between these two strains have provided ambiguous results from populations in the United States. In Colombia, we tested pre- and postzygotic isolation in these strains. Both strains showed postzygotic isolation for several life-history traits, including number of egg masses, number of larvae, number of females, pupal developmental time, female and male longevity, and female and male pupal weight. We observed a reduction of the number of hybrid females and a reduction in fertility in hybrids in S. frugiperda. These results suggest the possibility of Haldane's rule. Heterosis in the F1(2) and F2(1) generations was observed for number of larvae and adult longevity. This line presented a high standard deviation, suggesting instability in this cross. A possible effect of the X chromosome may explain the reduction in viability and sterility in F1 hybrids of host strains of S. frugiperda. No temporal isolation was observed between the corn and rice strains. Differences in longevity between corn and rice strains might be another form of temporal isolation between these strains, because differences in adulthood time might reduce the encounters between them and thus hybridization.

Gall-attacking behavior in phytophagous insects, with emphasis on Coleoptera and Lepidoptera

Abstract: Plant galls are induced by physicochemical interactions between plants and gall-inducing organisms, such as insects, mites, nematodes, fungi, bacteria and viruses. Organisms that are unable to create galls on plants, but feed on gall tissues induced by other species, are referred to as gall-attackers (gall-feeders) and include various insect orders (Thysanoptera, Hemiptera, Lepidoptera, Coleoptera, Diptera, and Hymenoptera). Gall-attacking weevils (Coleoptera) and moths (Lepidoptera) may have acquired their gall-feeding habits independently (i.e. cecidophages), whereas other gall-attacking insects, such as inquiline gall wasps (Hymenoptera) and gall midges (Diptera) may have evolved these habits from gall-inducing ancestors (i.e., inquilines). Most species of gall-attacking weevils feed only on galls (obligate cecidophages), while most gall-attacking moths feed on galls and also on ungalled or normal plant tissues (facultative cecidophages). Weevils may have acquired their gall-attacking habits independently from other types of feeding habits, such as leaf mining, seed-feeding, and bud-feeding, while moths may have acquired them from leaf-chewing and wood-boring. Studies on the effects of gall-attacking weevils on gall-inducing arthropods report a higher proportion of lethal effects than studies on effects from gall-attacking moths. Weevil larvae rarely move around food resources because they have no legs, while moth larvae can actively move among food resources using their prolegs. This difference in mobility between weevils and moth larva may be related to their differential gall-attacking behaviors and effects on gall-inducers. Cecidophages provide a model system for investigating the evolution of feeding habits and the ecology of species interactions.