Molecular differentiation of the Murraya paniculata Complex (Rutaceae: Aurantioideae: Aurantieae).

BACKGROUND: Orange jasmine has a complex nomenclatural history and is now known as Murraya paniculata (L.) Jack. Our interest in this common ornamental stemmed from the need to resolve its identity and the identities of closely related taxa as hosts of the pathogen 'Candidatus Liberibacter asiaticus' and its vector Diaphorina citri. Understanding these microbe-vector-plant relationships has been hampered by taxonomic confusion surrounding Murraya at both the generic and specific levels. RESULTS: To resolve the taxonomic uncertainty, six regions of the maternally-inherited chloroplastal genome and part of the nuclear-encoded ITS region were amplified from 85 accessions of Murraya and Merrillia using the polymerase chain reaction (PCR). Clustering used maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI). Chronograms were produced for molecular dating, and to test the monophyly of Murraya rigorously, using selected accessions of Murraya and 26 accessions of the Rutaceae and Simarubaceae. Sequence data from the ITS and chloroplastal regions suggest that Murraya paniculata (sensu (Swingle WT and Reece CR, The Citrus Industry, p. 190-430, 1967)) can be separated into four distinct but morphologically somewhat cryptic taxa: Murraya paniculata (sensu (Mabberley DJ, Taxon 65:366-371, 2016)), M. elongata, M. sumatrana and M. lucida. In addition, Murraya omphalocarpa was identified as a putative hybrid of M. paniculata and M. lucida with two geographically isolated nothovarieties representing reciprocal crosses. Murraya is monophyletic, and molecular dating suggests that it diverged from Merrillia during the Miocene (23-5 Ma) with this Murraya group speciating and dispersing during the Middle Miocene onwards. CONCLUSIONS: The accessions from Asia and Australasia used in this study grouped into biogeographical regions that match herbarium specimen records for the taxa that suggest natural allopatric distributions with limited overlap and hybridity. Murraya paniculata has been distributed around the world as an ornamental plant. The division of the Murraya paniculata complex into four species with a rare hybrid also confirms morphological studies.

Cropping System Diversification Reduces Severity and Incidence of Soybean Sudden Death Syndrome Caused by Fusarium virguliforme.

Current management of sudden death syndrome (SDS) of soybean, caused by Fusarium virguliforme, focuses on planting resistant varieties and improving soil drainage; however, these measures are not completely effective. A 6-year study evaluated the effects of cropping system diversification on SDS and soybean yield. SDS, root health, yield, and F. virguliforme density in soil were assessed in a naturally infested field trial comparing a 2-year cropping system consisting of a corn-soybean rotation and synthetic fertilizer applications with 3- and 4-year cropping systems consisting of corn-soybean-oat + red clover and corn-soybean-oat +alfalfa-alfalfa rotations, respectively, with both manure and low synthetic fertilizer rates. In 5 of 6 years, SDS incidence and severity were lower and yield higher in the 3- and 4-year systems than in the 2-year system. SDS severity and incidence were up to 17-fold lower in the diversified systems than in the 2-year system. Incidence and severity of SDS explained 45 to 87% of the variation in yield. Plants in the 2-year system generally showed more severe root rot and lower plant weights than plants in the diversified systems. F. virguliforme density in soil was up to fivefold greater in the 2-year system compared with the 4-year system. The processes responsible for the suppression of SDS and yield protection in the diversified cropping systems still need to be determined.

Host and environmental factors influencing 'Candidatus Liberibacter asiaticus' acquisition in Diaphorina citri.

BACKGROUND: Diaphorina citri is a vector of 'Candidatus Liberibacter asiaticus' (CLas) associated with citrus Huanglongbing. In this study, the infection and titers of CLas in the psyllid, were monitored for life cycle stage, sex, host-plant CLas titer, host-plant genotype, and ambient temperature. RESULTS: Acquisition efficiency of CLas by D. citri was highest in nymphs reared at 25 °C on a host plant with high CLas titers but was independent of the host genotypes assessed and of vector sex. We further observed that D. citri nymphs acquired CLas more rapidly than adults based on acquisition access periods (AAPs). CLas did not multiply in the alimentary canal, hemolymph, and salivary glands of adults for 18 days after a 3-day AAP as adult. However, CLas multiplication was detected in hemolymph and salivary gland of adults after the bacterium was acquired by nymphs. Eighty percent of salivary glands of adults contained CLas 18 days after a 3-day AAP as nymph compared to 10% 18 days after a 3-day AAP as adults. CONCLUSION: Different factors tested herein influenced CLas acquisition efficiency of D. citri, CLas multiplication and spread inside the psyllid. These observations serve to better understand mechanisms of CLas infection in D. citri. © 2018 Society of Chemical Industry.

Population diversity of Diaphorina citri (Hemiptera: Liviidae) in China based on whole mitochondrial genome sequences.

BACKGROUND: Diaphorina citri (Asian citrus psyllid; ACP) transmits 'Candidatus Liberibacter asiaticus' associated with citrus Huanglongbing (HLB). ACP has been reported in 11 provinces/regions in China, yet its population diversity remains unclear. In this study, we evaluated ACP population diversity in China using representative whole mitochondrial genome (mitogenome) sequences. Additional mitogenome sequences outside China were also acquired and evaluated. RESULTS: The sizes of the 27 ACP mitogenome sequences ranged from 14 986 to 15 030 bp. Along with three previously published mitogenome sequences, the 30 sequences formed three major mitochondrial groups (MGs): MG1, present in southwestern China and occurring at elevations above 1000 m; MG2, present in southeastern China and Southeast Asia (Cambodia, Indonesia, Malaysia, and Vietnam) and occurring at elevations below 180 m; and MG3, present in the USA and Pakistan. Single nucleotide polymorphisms in five genes (cox2, atp8, nad3, nad1 and rrnL) contributed mostly in the ACP diversity. Among these genes, rrnL had the most variation. CONCLUSION: Mitogenome sequences analyses revealed two major phylogenetic groups of ACP present in China as well as a possible unique group present currently in Pakistan and the USA. The information could have significant implications for current ACP control and HLB management. © 2018 Society of Chemical Industry.

Colossal pilomatrixoma.

We describe the largest reported case of pilomatrixoma in the literature. While pilomatrixomas typically present as small soft-tissue nodules of the head, neck and upper extremities, they can also present as much larger masses in atypical locations. When they present in their usual size, pilomatrixomas have typical imaging features and can be correctly diagnosed with imaging studies before histological confirmation. Their clinical and imaging diagnosis become challenging when they are very large, as in our case. A giant pilomatrixoma should also be considered for paediatric patients presenting with a large subcutaneous soft-tissue mass.

Primary parasitoids of red scale (Aonidiella aurantii) in Australia and a review of their introductions from Asia.

We used morphological and molecular differences to confirm the identities of red scale (Aonidiella aurantii) and yellow scale (A. citrina), and their primary parasitoids, in Australia. An extension to the distribution of yellow scale was confirmed. Six primary parasitoids of red scale were identified: Aphytis chrysomphali, A. lingnanensis, A. melinus, Comperiella bifasciata, Encarsia citrina, and E. perniciosi. With the exception of A. lingnanensis, these parasitoids, and a species of Aphelinus, were detected in association with red scale during studies in citrus orchards in coastal New South Wales between 2009 and 2012. Two races of A. melinus were recorded: one from the Indian Subcontinent, the other previously only recorded in China. The studies, and reviews of historical records, led us to conclude that 4 parasitoids, A. lingnanensis, C. bifasciata, and both species of Encarsia, were present in Australia before successful or unsuccessful formal introductions between 1902 and 1970. The A. melinus race previously recorded in China may also have been present before the Indian Subcontinent race was formally introduced in 1961. We suggest the possibility that the natural distribution of some of the parasitoids may include East and Southeast Asia, and parts of Australasia. We found no reports of native armored scales being recorded on species and hybrids of Citrus introduced to Australia, and no reports of introduced armored scales being recorded on native Rutaceae, including 6 species of Citrus. However, we subsequently recorded yellow scale on Geijera parviflora, a native rutaceous tree.

Genetic variation amongst biotypes of Dactylopius tomentosus.

The tomentose cochineal scale insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), is an important biological control agent against invasive species of Cylindropuntia (Caryophyllales: Cactaceae). Recent studies have demonstrated that this scale is composed of host-affiliated biotypes with differential host specificity and fitness on particular host species. We investigated genetic variation and phylogenetic relationships among D. tomentosus biotypes and provenances to examine the possibility that genetic diversity may be related to their host-use pattern, and whether their phylogenetic relationships would give insights into taxonomic relatedness of their host plants. Nucleotide sequence comparison was accomplished using sequences of the mitochondrial cytochrome c oxidase I (COI) gene. Sequences of individuals from the same host plant within a region were identical and characterized by a unique haplotype. Individuals belonging to the same biotype but from different regions had similar haplotypes. However, haplotypes were not shared between different biotypes. Phylogenetic analysis grouped the monophyletic D. tomentosus into 3 well-resolved clades of biotypes. The phylogenetic relationships and clustering of biotypes corresponded with known taxonomic relatedness of their hosts. Two biotypes, Fulgida and Mamillata, tested positive for Wolbachia (α-Proteobacteria), a common endosymbiont of insects. The Wolbachia sequences were serendipitously detected by using insect-specific COI DNA barcoding primers and are most similar to Wolbachia Supergroup F strains. This study is the first molecular characterization of cochineal biotypes that, together with Wolbachia sequences, contribute to the better identification of the biotypes of cochineal insects and to the biological control of cacti using host-specific biotypes of the scale.

Ant-coccid mutualism in citrus canopies and its effect on natural enemies of red scale, Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae).

Mutualistic relationships between honeydew-producing insects and ants have been widely recognized for several decades. Iridomyrmex rufoniger (Lowne) is the commonest ant species associated with black scale, Saissetia oleae (Olivier), in the citrus orchards of the mid latitudes of coastal New South Wales. Citrus trees with high densities of both red and black scale and high ant activity were identified and the results of excluding ants from half of those trees (using a polybutene band on each trunk) were compared with the results of not excluding ants from the other half. Trees with a low incidence of black scale and ants were also studied. Exclusion of ants from trees was soon followed by collapse of black scale populations because most individuals were asphyxiated by their own honeydew. Also, parasitism of the red scale by Encarsia perniciosi (Tower) and Encarsia citrina Craw was significantly higher than in the control trees over the following year, as was the predation rate on red scale due to three coccinellid predators, Halmus chalybeus (Boisduval), Rhyzobius hirtellus Crotch and Rhyzobius lophanthae (Blaisdell). In contrast, another coccinellid, Orcus australasiae (Boisduval), and a noctuid moth larva, Mataeomera dubia Butler, were seen in low numbers on banded (ant exclusion) trees, probably because of the low availability of their black scale prey, but were significantly higher on control trees apparently because of their invulnerability to ants.

'Candidatus Liberibacter asiaticus' Titers in Citrus and Acquisition Rates by Diaphorina citri Are Decreased by Higher Temperature.

'Candidatus Liberibacter asiaticus' is the most prevalent Liberibacter sp. associated with huanglongbing (HLB) in Brazil. Within São Paulo state (SP), HLB has spread more rapidly to and reached higher incidence in regions with relatively mild (cooler) summer temperatures. This suggests that climate can influence disease spread and severity. 'Ca. L. asiaticus' titers on soft, immature leaves from infected 'Valencia' sweet orange plants exposed to different temperature regimes and adult Diaphorina citri fed for 48 h on these plants for 'Ca. L. asiaticus' acquisition were determined by quantitative polymerase chain reaction in two experiments. The first experiment included plants with three levels of infection, three incubation periods (IPs), and air temperatures favorable (14.6 to 28°C) and unfavorable (24 to 38°C) to 'Ca. L. asiaticus'. The second included plants with severe late-stage infections, 10 IPs (based on 3-day intervals over 27 days), and three air temperature regimes (12 to 24, 18 to 30, and 24 to 38°C). Overall, 'Ca. L. asiaticus' titers and the percentages of 'Ca. L. asiaticus'-positive psyllids were lower in plants maintained at the warmer temperature regime (24 to 38°C) than in plants maintained in the cooler regimes. The results suggest that the lower incidence and slower spread of 'Ca. L. asiaticus' to warmer regions of SP are related to the influence of ambient temperatures on titers of 'Ca. L. asiaticus' in leaves.

Encephalitis with thalamic and basal ganglia abnormalities: etiologies, neuroimaging, and potential role of respiratory viruses.

BACKGROUND: Encephalitis is a severe neurological syndrome with devastating consequences. Despite extensive testing, the etiology often remains unknown. Involvement of the thalamus or basal ganglia (T/BG) occurs in a subset of patients with encephalitis and may be an important etiological clue. In order to improve diagnosis of T/BG patients, we reviewed this subgroup within the California Encephalitis Project (CEP). METHODS: Data from T/BG cases enrolled in CEP were retrospectively reviewed. Cases were stratified by age and grouped by etiological classification: infectious, postinfectious, and noninfectious. Neuroimaging reports were examined and compared between etiologies. RESULTS: T/BG neuroimaging abnormalities were reported in 6% of 3236 CEP cases. An etiology was found in 76%: 37% infectious, 16% postinfectious, and 23% noninfectious. The most frequently identified infectious agents were respiratory viruses, accounting for 31%, predominantly in children. Other infections more common in the T/BG group included Creutzfeldt-Jakob disease, arbovirus, and Mycobacterium tuberculosis. Infectious and postinfectious cases had higher median cerebrospinal fluid white blood cell count than noninfectious etiologies. Notably, T/BG neuroimaging characteristics were associated with distinct etiologies. In particular, symmetric hemorrhagic abnormalities involving the thalamus were most frequently found within the respiratory virus group. CONCLUSIONS: T/BG involvement in patients with suspected encephalitis was associated with specific etiologies. In addition to agents with established predilection for the T/BG such as M. tuberculosis and arboviruses, a surprisingly high number of cases were associated with respiratory viruses, especially in children. Neuroimaging abnormalities in such patients can aid clinicians in narrowing the etiological scope and in guiding testing.

Hybridization between Dactylopius tomentosus (Hemiptera: Dactylopiidae) biotypes and its effects on host specificity.

Dactylopius tomentosus is composed of biotypes adapted to different Cylindropuntia species. One biotype is an important biological control agent of C. imbricata in South Africa while another has the potential for the control of C. fulgida var. fulgida. These two weed species occur in sympatry in some areas of South Africa, so the introduction of the second biotype could result in hybridization, which, in turn, could impact on the biological control programs through altered host specificity and fitness of the hybrids. To anticipate what might happen, reciprocal crosses were made between the two biotypes, and the biological performance of the resultant hybrids was compared with that of each parental lineage on C. imbricata and C. f. var. fulgida. The biotypes interbred freely and reciprocally in the laboratory. Comparisons of crawler and adult female traits showed differences in performance that were dependent on the origin of the maternal and paternal genomes. However, when all traits were combined into a 'fitness index', both hybrids clearly outperformed the parental lineages. The increase in fitness shown by the hybrids over their maternal lineage was greater on the alternative host of the maternal parent than on the natural host of the maternal parent. Therefore, in areas where the two cacti occur in sympatry, hybridization between the biotypes is not expected to be detrimental to the biological control of either weed.

Determination of biotypes of Dactylopius tomentosus (Hemiptera: Dactylopiidae) and insights into the taxonomic relationships of their hosts, Cylindropuntia spp.

Host specialization to form biotypes is common among phytophagous insects, and it has been hypothesised that biotypes of Dactylopius tomentosus L. (Hemiptera: Dactylopiidae) occur. D. tomentosus is an important biological control agent for Cylindropuntia cacti when they occur as weeds. Additionally, there is uncertainty surrounding the taxonomic status of some species of Cylindropuntia. This study aimed to confirm the existence of D. tomentosus biotypes and to assess whether host specialization can help to resolve this systematic uncertainty. For this study, the host specificity and performance of ten provenances of D. tomentosus collected from C. cholla, C. fulgida var. fulgida, C. imbricata, C. f. var. mamillata, C. rosea and C. tunicata and reared on C. cholla, C. fulgida var. fulgida, C. imbricata and C. rosea were investigated. Five life-history parameters were measured including: crawler development time and survival, female development time, and the weight and number of eggs produced by females. Results revealed significant variation in host specificity with provenances either thriving, surviving or dying on the different hosts, thus demonstrating the existence of biotypes. Also, host specificity was related to host species and not to the geographic locality from which either the host or provenance was sourced. These findings suggest that the characteristics of Cylindropuntia species may differ sufficiently, there by presenting different selection pressures that induce and sustain distinct biotypes of D. tomentosus. The observed host use patterns of the biotypes separated the plant species into two groups that accorded with known phylogenetic relationships among Cylindropuntia species, suggesting that biotypes can be used to elucidate their taxonomic relatedness. Besides advancing our knowledge of the ecology and evolution of D. tomentosus, these novel findings have important implications for the biological control of Cylindropuntia species.

Distinguishing suitable biotypes of Dactylopius tomentosus (Hemiptera: Dactylopiidae) for biological control of Cylindropuntia fulgida var. fulgida (Caryophyllales: Cactaceae) in South Africa.

Cylindropuntia fulgida (Engelmann) F.M. Knuth var. fulgida (Engelmann) F.M. Knuth (Cff) (Caryophyllales: Cactaceae) is native to Mexico and Arizona and was introduced into South Africa for ornamental purposes. It subsequently became highly invasive, necessitating control. The cochineal insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), was selected as a potential biological control agent based on its restricted host range among Cylindropuntia species and previous success in controlling C. imbricata (DC.) F. Knuth (Ci). Eight D. tomentosus provenances (Cholla, Cholla E, Fulgida, Mamillata, Imbricata, Tunicata U, Tunicata V and Rosea) from Cylindropuntia species in their native ranges were reared on Cff, whilst Cholla and Imbricata were also reared on Ci. Large differences were found in the development and survival of crawlers, and in the reproductive capacity of females. Three subjective categories of provenance interaction with host plants were identified based on a fitness index (FI) calculated from data relating to crawler survival, female development time and fecundity: (i) thriving (FI > or = 1) - insects had shorter developmental times, high crawler survival and highly fecund females (Cholla); (ii) surviving (FI<1 but >0) - insects had extended development times, low crawler survival and low fecundity (Imbricata, Fulgida and Mamillata); and (iii) dying (FI = 0) - insects died before or at the second instar (Rosea, Tunicata U and Tunicata V). Cholla, therefore, is highly suitable for biological control of Cff in South Africa. In addition, Cholla thrived on Cff but only survived on Ci whilst, in contrast, Imbricata thrived on Ci but only survived on Cff. This differential ability of provenances to thrive or survive on different host plants demonstrated that host adapted biotypes of D. tomentosus exist; therefore, biotypes should be taken into account when considering this species as a biological control agent of cactus weeds.

The influence of sublethal deposits of agricultural mineral oil on the functional and numerical responses of Phytoseiulus persimilis (Acari: Phytoseiidae) to its prey, Tetranychus urticae (Acari: Tetranychidae).

Occasional pesticide application in integrated pest management to at least part of a crop requires that any biological control agents must re-invade previously sprayed areas in order that resurgent pests can be constrained. The ability of the phytoseiid predatory mite Phytoseiulus persimilis to feed on adult two-spotted spider mite (TSSM) Tetranychus urticae on excised leaf discs in both control conditions and in a treatment with a sub lethal residue of agricultural mineral oil (AMO) was assessed. The predator exhibited a Type II functional response with the asymptote significantly higher in the AMO conditions due to the fact that the prey grew slower and reached a smaller size in this treatment. In terms of prey volume eaten, the satiation level of the predator was unchanged by the AMO deposits. The numbers of eggs produced by adult P. persimilis females at densities of 4, 8 and 16 TSSM adult females/disc in the control were significantly higher than those in the AMO treatment, but were similar for the higher density levels, 32 and 64 prey per disc. Thus the functional response in terms of volume of prey eaten explained the numerical response in terms of predator eggs produced. The presence of AMO deposits when the prey were at high density had no effect on predator efficiency (volume eaten) but resulted in a lower intake than that in control conditions when there was a greater distance between prey.

The biology of Dactylopius tomentosus (Hemiptera: Dactylopiidae).

Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae) is a cochineal insect whose host range is restricted to Cylindropuntia species (Caryophyllales: Cactaceae). This insect has been utilized successfully for biological control of Cylindropuntia imbricata (Haw.) F.M. Knuth in Australia and South Africa. Despite this, its biology has not been studied previously, probably due to the widely held belief that the biology of all Dactylopius species is similar. This study investigated the life cycle and the morphological and reproductive characteristics of D. tomentosus. Results revealed some unique characteristics of D. tomentosus: (i) eggs undergo a much longer incubation period, an average of 17 days compared to <1 day in its congeners; (ii) eggs are laid singly but are retained as an egg mass secured in a mesh of waxy threads attached to the female; (iii) the developmental times of males and females are longer compared to other Dactylopius spp. due to a longer egg incubation period; (iv) D. tomentosus does not undergo parthenogenesis; (v) D. tomentosus is smaller in size than its congeners; and (vi) male mating capacity and reproductive potential were both high and variable between males. There was a significant, strong, positive relationship (r = 0.93) between female mass and fecundity, whereas the relationship between the number of females mated per male that became gravid and their fecundity was negative (r = -0.68). Besides contributing to our knowledge of this economically important species, the finding of unique characteristics of D. tomentosus biology underlines the need to study each species in this genus.

Global gene expression profiling and histochemical analysis of the developing human fetal pancreas.

AIMS/HYPOTHESIS: An immunohistochemical and genomic analysis of human pancreatic development from 9-23 weeks of fetal age was undertaken to provide a comparative analysis of human and murine islet development. METHODS: Human fetal pancreases obtained at gestational ages 9-23 weeks were processed in parallel for immunohistochemistry and gene expression profiling by Affymetrix microarrays. RESULTS: By 9-11 weeks, the pancreas was made up principally of mesenchymal tissue infiltrated by branched epithelial structures containing scattered hormone-negative neurogenin3-positive endocrine cells. Protoacinar structures emerged by 15-19 weeks, along with clusters of endocrine cells producing either glucagon or insulin. By 20-23 weeks, vascularised islet-like structures appeared. More than 70% of endocrine cells produced a single hormone at any age. Analysis of Ki67 immunoreactivity showed that the replicative rate of endocrine cells was low and suggested that the endocrine expansion was derived from hormone-negative precursors. Insulin, glucagon, somatostatin, ghrelin and pancreatic polypeptide transcripts were present at 9-10 weeks and increased progressively, commensurate with the expansion of endocrine cell volume. The human equivalent of a mouse endocrine secondary transition was not evident, neither in terms of morphology nor in dramatic changes in endocrine-specific transcriptional regulators. By contrast, exocrine genes showed a marked transition at around 11 weeks, associated with a greater than sixfold increase in exocrine gene transcripts. CONCLUSIONS/INTERPRETATION: The observed extension of terminal differentiation of human endocrine tissue into late gestation is in contrast with findings in the mouse. It indicates that the human fetal pancreas could provide an abundant islet precursor cell population that could be expanded ex vivo for therapeutic transplantation.

Development of Epiphyas postvittana (Lepidoptera: Tortricidae) on leaves and fruit of orange trees.

Development of Epipyas postvittna (Walker) (Lepidoptera: Tortricidae), on leaves and fruit of 'Valencia', 'Washington navel', and 'Navelina' orange trees was studied under constant and fluctuating temperatures. E. postvittna was able to complete its life cycle feeding exclusively on leaves or fruit of orange trees. However, larval survival rate was very low (< 20%) on orange tissues compared with that on noncitrus hosts. Among the four types of orange tissues, young orange leaves and fruit afforded larvae higher survival rates than mature orange leaves and fruit. Fruit (young or mature) produced heavier pupae than leaves (young or mature). Larvae developed more slowly on mature orange fruit than on other orange materials and more slowly on orange leaves than on leaves of most noncitrus hosts. Degree-day accumulations based on the fastest developmental rates obtained in this study suggested that E. postvittna is capable of completing 4.4-4.7 generations per year in orange orchards in the Riverina region of New South Wales, Australia. Implications of the results in the management of the insect in citrus are discussed.

Evaluation of mating disruption for control of lightbrown apple moth (Lepidoptera: Tortricidae) in citrus.

Three large-scale mating disruption (MD) trials were conducted from 2001 to 2004 in an organic citrus orchard in inland southeastern Australia to evaluate the effectiveness of the MD dispenser Isomate LBAM Plus in controlling lightbrown apple moth, Epiphyas postvittana (Walker), in citrus. At the application rate of 364-728 dispensers per ha, the dispensers reduced pheromone trapping of E. postvittana to almost undetectable levels for approximately 6 mo in the treated area. During this period, most sentinel females in the treated area failed to mate. Infestation by E. postvittana in the treated area was reduced by >50%. If distributed in citrus orchards in late winter (August), the dispensers can be expected to remain effective until next February in southeastern Australia, covering the period when most fruit scarring caused by its larvae occurs.