SEX PHEROMONE COMPONENTS OF HELICOVERPA ARMIGERA:CHEMICAL ANALYSIS AND FIELD TESTS*

Abstract

Gas chromatographic and mass spectral analyses were conducted on the pheromone gland extracts of female moth of Helicoverpa armigera (Lepidoptera:Noctuidae). Saturated aldehyde (16:Ald), (Z)‐9‐hexadecenal (Z‐9–16:Ald), (Z)‐11‐hexadecenal (Z‐11–16:Ald), hexade‐canol (16:OH) and (Z)‐11‐hexadecenol (2–11–16:OH) were found from gland extracts in the ratio of 6.1:4.5:100:3.5:8.8. In field tests of Shandong and Shanxi Provinces, 2 mg blends of Z ‐11–16:Ald and Z‐9–16:Ald (97:3) applied on a rubber dispenser effectively attracted H. armigera males. The addition of 4%‐7%16:Ald to the binary mixture caused increase over that of the binary mixture. The addition of 1%Z‐11–16:OH to binary or trinary mixture may reduce catches, while addition of 5% Z‐11–16:OH reduced catches singnificantly.

Comparative study of sex pheromone composition and biosynthesis in Helicoverpa armigera, H. assulta and their hybrid

“…H. armigera and H. assulta are sympatric, closely related species in and around China. In H. armigera, the ratio of the major pheromone component, Z11-16:Ald and the minor component, Z9-16:Ald varied from 100:6.5 to 100:2.5 (Nesbitt et al, 1980;Wu et al, 1997;Dunkelblum et al, 1980;Kehat and Dunkelblum, 1990). The variation could have been caused by collection of experimental insects from different areas.…”

Pheromone Reception in Moths

“…For H. armigera, more than seven pheromone components have been identified from the pheromone glands of females. 14,161,162 When the pheromone components Z11-16: Ald and Z9-16:Ald are mixed at a ratio of 99:1 as compared to 90:10, attractiveness to the males is significantly increased. 161,163 Z9-14:Ald was shown to strengthen the attraction of males at low concentrations, while suppressing attraction at higher concentrations, when mixed with the pheromone components.…”

“…8,9 The variation of the double bond position and the differentiation of the pheromone component proportions may underlie reproductive isolation barriers between species. 4,[10][11][12][13][14] This is exemplified by the two sex pheromone races of the European corn borer moth Ostrinia nubilalis, E and Z, which produce opposite ratios of isomers of the major female sex pheromone components, E11-and Z11-14:acetate. 15, 16 Lassance et al found that allelic variation in a fatty-acyl reductase gene that is essential for pheromone biosynthesis accounts for the female pheromone variation.…”

Functional Specificity of Sex Pheromone Receptors in the Cotton Bollworm Helicoverpa armigera

“…One of the most important sex pheromone component for the species is (Z)-11-hexadecenal (Z11-16:Ald), which alone can attract a small number of male moths. Z9-16:Ald is generally thought to be an important minor component [25], [26], [27], [28], [29]. Adding Z9-16:Ald to Z11-16:Ald with ratio from 1∶99 to 10∶90 caused a significant increase in trap catch of male H. armigera [27], [30], [31].…”

“…Adding Z9-16:Ald to Z11-16:Ald with ratio from 1∶99 to 10∶90 caused a significant increase in trap catch of male H. armigera [27], [30], [31]. Many other components were also identified in sex pheromone glands of female H. armigera , including tetradecanal (14:Ald), (Z)-11-tetradecenol (Z11-14:OH), (Z)-9-tetradecanal (Z9-14:Ald), 16:Ald, Z7-16:Ald, 16:OH, Z9-16:OH, Z11-16:OH, Z11-14:Ald and Z11-16:Ac [27], [29], [32], [33]. Of these, Z11-16:OH and 16:OH are attraction inhibitors when added to attraction blends [27], [29], [30].…”