Morphological Characterization of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae: Heliothinae)

Abstract

The cotton bollworm Helicoverpa armigera (Hübner) is a widespread lepidopteran pest found in various crops worldwide. This highly polyphagous species, commonly found both in the Old and New World, has caused significant economic damage as an invasive agricultural pest in Brazil since 2013. The goal of the present study is to provide a detailed morphological assessment of adults and immature stages of H. armigera, as this species is often confused with H. zea (Boddie), a congeneric species that is native to the New World. The biology data were acquired during four full life cycles, and observations on general behavior, nocturnal habits of larvae and adults, and sensitivity of larvae to humidity were recorded. Larval chaetotaxy differs between the first and the remaining instars, which bear L2 on the meso- and metathorax and L3 on A3 through A6, along with conspicuous chalazae and longitudinal bands. Important morphological characters of this species include the following: eggs with four micropylar openings, lined with 12 cells arranged in the shape of a rosette; pupa adecticous and obtect, with prominent spiracles; adults with the distal antennomere striate. Adults exhibit sexual dimorphism in the number of setae on the frenulum and spines on the prothoracic leg. Illustrations of the critical morphological features of this species are provided.

Life-History Parameters of Striacosta albicosta (Lepidoptera: Noctuidae) Under Laboratory Conditions

“…Pupae were monitored daily to record the emergence of adults and maintain moisture of the sand by adding 10 ml of distilled water as needed. On the second day after pupation, when the cuticle was hardened, each insect was weighed using a semianalytical balance (precision of 0.01 g) and sex determination was performed following Queiroz-Santos et al (2018). Considering that precise sex determination is only possible during the pupal stage, the identity of each larva was preserved throughout the study.…”

Role of nutritional composition in the development and survival of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on artificial diet and natural hosts

“…At this time, 0.5 cm 3 of water-moistened vermiculite was added to each plate to provide moisture. After pupal metamorphosis (48 h), the individuals were weighed on semi-analytical scales accurate to one-thousandth of a gram and examined to identify sex (Queiroz-Santos et al ., 2018). The daily maintenance of the pupae was restricted to maintaining the humidity of the vermiculite, by applying a few drops of water until the emergence of adults.…”

A review on biological interactions and management of the cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae)

“…The eggs are subspherical in shape, with an average length between 0.42 and 0.60 mm and a width of 0.40–0.55 mm (Ali et al., 2009). They are cream‐white in colouration when freshly laid, darkening slightly after 2–3 days before turning brown prior to hatching (Queiroz‐Santos et al., 2018). Ali et al.…”

“…(2009) reported an average of 3.4 ± 0.1 days for the incubation period. The micropylar region is convex, possesses at least four micropylar openings and is surrounded by a rosette formed by 12 cells (Queiroz‐Santos et al., 2018).…”

“…The spiracles and tubercles are brown to black, giving a spotted appearance, with the prothoracic legs also being dark brown to black (Ali et al., 2009; Herald & Tayde, 2018). Marbling of light and dark brown areas becomes increasingly conspicuous in the fifth instar (Ali et al., 2009; Herald & Tayde, 2018; Queiroz‐Santos et al., 2018). The sixth instar may take on one of two distinct body colouration patterns.…”