(7Z)-Tricosene Improves Pheromone Trap Catch of Raspberry Bud Moth, Heterocrossa rubophaga.

Heterocrossa rubophaga, the raspberry bud moth, is a pest of commercial Rubus berry crops and wild Rubus species. Its pheromone was initially identified as a single component, (7Z)-nonadecen-11-one. Here we report further investigation of this carposinid pheromone including volatile collection, gland extraction, mass spectrometry, microchemical analysis, electrophysiology and field testing. The alkene (7Z)-tricosene was identified from female gland extracts and the synthetic compound gave antennal responses from the male moth. Field testing of (7Z)-tricosene showed that it was unattractive alone but in combination with (7Z)-nonadecen-11-one it more than doubled male moth trap catch for all doses tested compared to that of (7Z)-nonadecen-11-one alone. We recommend a blend of 300 µg of (7Z)-nonadecen-11-one and 300 µg of (7Z)-tricosene as an improved monitoring tool for raspberry bud moth for use by berry growers. This is the second report of the Z-alkene as a pheromone component in the Carposinidae family among the three carposisnid pheromones identified to date.

Patterns of mitochondrial haplotype diversity in the invasive pest Epiphyas postvittana (Lepidoptera: Tortricidae).

The light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), is a horticultural pest of Australia and New Zealand that has more recently invaded Hawaii, Europe, and California. A 2,216-bp region of the mitochondrial genome containing the cytochrome oxidase I and II genes was sequenced from 752 individuals. Haplotype network analyses revealed a major split between a predominantly Western Australian clade and all other samples, suggestive of either a deep genetic divergence or a cryptic species. Nucleotide and haplotype diversity were highest in the country of origin, Australia, and in New Zealand populations, with evidence of haplotype sharing between New Zealand and Tasmania. Nucleotide and haplotype diversity were higher in California than within the British Isles or Hawaii. From the total of 96 haplotypes, seven were found in California, of which four were private. Within California, there have been at least two introductions; based on genetic diversity we were unable to assign a likely source for a single moth found and eradicated in Los Angeles in 2007; however, our data suggest it is unlikely that Hawaii and the British Isles are sources of the major E. postvittana population found throughout the rest of the state since 2006.

Prospects for the control of apple leaf midge Dasineura mali (Diptera: Cecidomyiidae) by mass trapping with pheromone lures.

BACKGROUND: Apple leaf midge, Dasineura mali (Kieffer), poses quarantine issues for some apple export markets because larvae occasionally pupate in the stem end and calyx of fruit. Pheromone-baited oil-filled containers were used in 1 ha orchard plots to trap adult male D. mali in order to test the potential for mass trapping to reduce populations. RESULTS: Mass-trapped plots had 97% fewer adult males in pheromone traps and 48% fewer larvae per shoot in the second D. mali generation compared with untreated areas. Oil traps caught on average 900 000 D. mali per plot over 11 weeks during the second and third generations. Catches averaged 9200 per trap at plot corners. By comparison, catches were 51% lower 10-25 m away along borders, 80% lower at the midpoint of borders and 95% lower >7 m from plot edges. Fruit infestation was low (four out of 8000 apples). CONCLUSION: The attractiveness of the pheromone, monophagous habit and low mobility of D. mali enhance the prospects for successful mass trapping. Countering this are high populations, multivoltinism and aspects of mating behaviour. Mass trapping would probably have been more effective had it been in place season long and conducted over successive years. It needs refinements and more study before becoming a feasible control option for D. mali.

Pollinator-prey conflict in carnivorous plants.

Most carnivorous plants utilize insects in two ways: the flowers attract insects as pollen vectors for sexual reproduction, and the leaves trap insects for nutrients. Feeding on insects has been explained as an adaptation to nutrient-poor soil, and carnivorous plants have been shown to benefit from insect capture through increased growth, earlier flowering and increased seed production. Most carnivorous plant species seem to benefit from insect pollination, although many species autonomously self-pollinate and some propagate vegetatively. However, assuming that outcross pollen is advantageous and is a more important determinant of reproductive success than the nutrients gained from prey, there should be a selective pressure on carnivorous plants not to feed on their potential pollen vectors. Therefore, it has been suggested that carnivorous plants are subject to a conflict, often called the pollinator-prey conflict (PPC). The conflict results from a trade-off of the benefits from feeding on potentially pollinating insects versus the need to use them as pollen vectors for sexual reproduction. In this review we analyze the conditions under which a PPC may occur, review the evidence for the existence of PPCs in carnivorous plants, and explore the mechanisms that may be in place to prevent or alleviate a PPC. With respect to the latter, we discuss how plant signals such as olfactory and visual cues may play a role in separating the functions of pollinator attraction and prey capture.

(Z)-11-Hexadecenal and (3Z,6Z,9Z)-tricosatriene: sex pheromone components of the red banded mango caterpillar Deanolis sublimbalis.

The sex pheromone of the red banded mango caterpillar, Deanolis sublimbalis (Lepidoptera: Crambidae), a serious pest of the mango Mangifera indica (Anacardiaceae) in India and Southeast Asia and a recent invader into northern Australia, has been identified. Three candidate compounds were identified from pheromone gland extracts of female moths, using gas chromatography (GC), GC-electroantennographic detection and GC-mass spectrometric analyses, in conjunction with dimethyldisulfide derivatization. Field bioassays established that both (Z)-11-hexadecenal (Z11-16:Ald) and (3Z,6Z,9Z)-tricosatriene (3Z,6Z,9Z-23:Hy) were required for attraction of male D. sublimbalis moths, and 1000 microg of a 1:1 mix of Z11-16:Ald and 3Z,6Z,9Z-23:Hy was more attractive to male moths than caged virgin females. However, the binary blend was only attractive when the isomeric purity of the monounsaturated aldehyde was >99%, suggesting that the (E)-isomer was inhibitory. Although (Z)-11-hexadecen-1-ol (Z11-16:OH) was tentatively identified in gland extracts, the addition of this compound to the binary blend did not increase the numbers of moths captured. The pheromone can now be used in integrated pest management strategies.

(11Z,13E)-Hexadecadien-1-yl acetate: sex pheromone of the grass webworm Herpetogramma licarsisalis-identification, synthesis, and field bioassays.

The grass webworm Herpetogramma licarsisalis (Lepidoptera: Crambidae), which has recently established in pasture in Northland, New Zealand, is an important pest of many tropical and subtropical grasses. Two pheromone components, (Z)-11-hexadecen-1-yl acetate (Z11-16:Ac) and (11Z,13E)-hexadecadien-1-yl acetate (Z11,E13-16:Ac), were identified in pheromone gland extracts of female moths by gas chromatography (GC), GC-electroantennographic detection, and GC-mass spectrometry in conjunction with microchemical tests (dimethyldisulfide and 4-methyl-1,2,4-triazoline-3,5-dione derivatizations). Z11,E13-16:Ac and its geometric isomer (11E,13Z)-hexadecadien-1-yl acetate (E11,Z13-16:Ac) were synthesized via stereoselective Wittig reactions, and the identity of the diene present in the pheromone glands was confirmed to be Z11,E13-16:Ac. Field bioassays at Indooroopilly in Brisbane, Australia, established that Z11,E13-16:Ac was necessary and sufficient for attraction of male grass webworm moths and that the corresponding alcohol, (11Z,13E)-hexadecadien-1-ol (Z11,E13-16:OH), had a strong inhibitory effect on trap catches at the ratios tested. When mixed with Z11,E13-16:Ac in various ratios, Z11-16:Ac had no effect on the attractiveness of lures.