Longtailed Mealybug Research Articles

New Monoterpenoid as the Sex Pheromone of Spanish Populations of the Longtailed Mealybug Pseudococcus Longispinus (Hemiptera: Pseudococcidae).

Pseudococcus longispinus (Targioni-Tozzetti) (Hemiptera: Coccoidea: Pseudococcidae), a polyphagous and cosmopolitan pest native to Australia, is a highly damaging pest for numerous crops of economic importance. The sex pheromone of this species (2-(1,5,5-trimethylcyclopent-2-en-1-yl)ethyl acetate), currently used for pest monitoring purposes, was not attractive to males in field experiments conducted in Spanish persimmon orchards infested with this mealybug. The virgin and mated female volatile profiles of these P. longispinus populations were studied by the volatile collection of effluvia in Porapak-Q. The resulting extracts were analyzed by gas chromatography coupled to mass spectrometry (GC-MS), revealing a new compound specific to virgin females and different from the previously described sex pheromone. Based on GC-MS data and nuclear magnetic resonance experiments, we envisaged monoterpene 2-(1,5-dimethyl-4-methylenecyclopent-2-en-1-yl)ethyl acetate as the new sex pheromone candidate, which was synthesized and shown to be attractive in the field to P. longispinus males of the Spanish population.

Metagenomic ecosystem monitoring of soft scale insects and mealybug communities

Soft scale insects and mealybugs are phloem-feeding Hemipterans that are considered major pests in agriculture and horticulture throughout the world. However, correct taxonomic identification in the field can be difficult, making it hard for growers to implement control strategies. In viticulture, soft scale insects are a major issue due to their ability to secrete honeydew, which facilitates the development of sooty mould, and their propensity for being transmission vectors of several viral diseases of grapevine. To facilitate the rapid identification and quantification of vineyard-associated insects a metagenomic-based bioinformatic pipeline (MitoMonitor) was developed for generalised ecosystem monitoring, which automated the assembly and classification of insect mitochondrial genomes from shotgun sequencing data using the Barcode of Life Database API. The proof-of-concept application of MitoMonitor on metagenomic data obtained from eight samples from South Australian vineyards led to the identification of Parthenolecanium corni (European fruit scale)—which was thought to be absent in Australian vineyards—as the dominant coccoid species across the samples, with less frequent, and also lower abundance of Pseudococcus viburni (obscure mealybug) and Pseudo. longispinus (long-tailed mealybug). In addition, parisitoidism by Coccophagus scutellaris (Aphelinidae) wasps was also detected. The discovery of Parth. corni as a member of scale communities in these samples has significant implications for the development of effective control strategies for this important group of pests in affected areas.

Do hyperparasitoids disrupt the biological control of Pseudococcus longispinus in persimmon?

The long-tailed mealybug, Pseudococcus longispinus, represents a threat for several crops worldwide and has become the main pest of Mediterranean persimmon. Parasitoids are the primary natural enemies of P. longispinus, but their efficacy is highly variable among crops and countries. Here, we tested whether hyperparasitoids hinder the biological control of P. longispinus in Mediterranean persimmon. For this aim, we sampled 16 orchards across two consecutive years and measured the impact of primary parasitoids and hyperparasitoids on P. longispinus. Anagyrus fusciventris was the most abundant and widely distributed primary parasitoid. Population growth rate of the mealybug became negative when parasitism was higher than 30%. The hyperparasitoids Chartocerus sp. and Prochiloneurus sp. emerged mostly from large mealybug mummies that were used by A. fusciventris females. However, and contrary to our hypothesis, hyperparasitism did not affect the population growth rate of P. longispinus within the same year, suggesting that the high abundance of hyperparasitoids did not disrupt the biological control of this invasive mealybug. Based on these results, we propose several strategies based on conservation and augmentative biological control to improve the management of P. longispinus in persimmon.

Pseudococcus longispinus (long-tailed mealybug)

Pseudococcus longispinus (long-tailed mealybug)

Pseudococcus longispinus (long-tailed mealybug)

This datasheet on Pseudococcus longispinus covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Natural Enemies, Impacts, Prevention/Control, Further Information.

Prospects of neem and citronella oil against Pseudococcus longispinus (hemiptera: Pseudococcidae) on Phalaenopsis

Synthetic insecticides are still widely used in gardens and greenhouses of ornamental crops to reduce populations of insect pests and preserve flower quality. The improper and unwise use of synthetic insecticides has caused various negative impacts on humans, insect pests, and the environment. Therefore, the quest for unharmed insecticides and environmentally friendly is being sought. The purpose of this study was to examine the effectiveness of botanical insecticide formulation of neem and citronella oil to control long-tailed mealybug Pseudococcus longispinus. Four insecticide concentrations of neem, citronella oil and its mixtures (0.5, 1, 1.5, 2 per cent) were tested for their effectiveness by adding each with Latron at 0.5% as an emulsifier. Bioassays were performed in the laboratory by spraying insecticides on Phalaenopsis leaves infested with P. longispinus groups of one size class, mostly represented by the third instar nymphs. The results revealed that all insecticides tested caused mortality after 24 hours. The combination of neem and citronella in 1.5% provided adequate protection by reducing P. longispinus populations by up to 86%. Thus, botanical insecticides can be recommended as a viable alternative to synthetic insecticides against P. longispinus which infested orchids.

The morphology and abundance of longtailed mealybug (Pseudococcus longispinus) on ornamental plant, Aglaonema spp. in Jambi city, Indonesia

Aglaonema plants are currently in great demand among the public. It becomes a trend and business field for lovers of ornamental plants since it has unique leaves with various beautiful attractive colors and high aesthetic value. One of the pests that attack the aglaonema plant is Pseudococcus longispinus. This pest can inhibit the growth of aglaonema plants. This exploratory research revealed the morphology and number of different species of Pseudococcus longispinus pest and the factors that influence its abundance. Conducted through surveys in several aglaonema gardens located in the yards of residents’ houses, there are five research sites that have 15 varieties of aglaonema plants surveyed in Jambi. The highest number of Pseudococcus longispinus was found on the Aglaonema siam aurora, and the lowest abundance was found in the Aglaonema snow white plant.

Longtailed Mealybug Pseudococcus longispinus (Targioni Tozzetti) (Insecta: Hemiptera: Pseudococcidae)

The longtailed mealybug, Pseudococcus longispinus (Targioni Tozzetti), is a widely-distributed pest that feeds on many economically important hosts, particularly tropical fruits and ornamentals. This mealybug gets its common name from the two long, waxy filaments protruding from the last abdominal segment of adult females (Figure 1). This characteristic helps distinguish it from other mealybugs that may feed on the same host plants, although these long filaments sometimes break off.

Monitoring and control strategies for mealybug of persimmon in Australia

Mealybug is the most important pest of persimmon in temperate environments and one of the three most important pests in subtropical growing areas of Australia. The species of concern to the sweet persimmon industry are citrus mealybug (Planococcus citri), longtail mealybug (Pseudococcus longispinus) and citrophilous mealybug (Pseudococcus calceolarieae). The dominant pest species in subtropical environments (e.g., Queensland) is citrus mealybug, whereas longtailed and citrophilous mealybug predominate in the temperate growing regions across southern Australia. Little is known of the population dynamics of these mealybug pest species, particularly in relation to crop phenology. Knowledge of the timing of mealybug infestation and particularly the presence of the susceptible juvenile stages, is a key factor in the effective control of mealybug. Several methods for monitoring mealybug population dynamics were investigated, including pheromone traps, sticky bands and the visual inspection of roots. Field trials conducted to establish the efficacy of preharvest chemical treatments in controlling mealybug. The objective was to replace broad-spectrum insecticides with chemistry compatible with the use of predators and an IPM strategy. Field trials included clothianidin, spirotetramat, sulfoxaflor, thiamthoxam, and imidacloprid, as well as the timing of applications of clothianidin. The effectiveness of monitoring techniques and preharvest insecticide treatments will be discussed.

24, 48 and 72 hour contact toxicity test of peppermint (Mentha piperita), garlic (Allium sativum L.) and lemon (Citrus limon L.) essential oil on the long-tailed mealybug (Pseudococcus longispinus)

24, 48 and 72 hour contact toxicity test of peppermint (Mentha piperita), garlic (Allium sativum L.) and lemon (Citrus limon L.) essential oil on the long-tailed mealybug (Pseudococcus longispinus)

MAINTAINING TABLE GRAPE QUALITY BY APPLYING QUARANTINE TREATMENTS DURING COOLING

‘Red Globe’, ‘Thompson Seedless’ and ‘Crimson Seedless’ grapes were picked directly into ventilated polystyrene boxes and chilled for 6-8 h to approximately 20°C before being fumigated with 52.6 g m-3 ethyl formate + 21.6% carbon dioxide to treat external pests and stages likely to be found in harvested produce: 1st-3rd instar light brown apple moth and red back spiders; long-tailed mealy bug crawlers; adult two spotted spider mites, plague thrips and western flower thrips. Fumigation was applied for 2.5 h at 21°C in a refrigerated shipping container (68 m3) while cooling to 15°C. Cooling was continued to 1 and 2°C for 16 and 18 days, respectively to simulate control of Mediterranean and Queensland fruit flies. The results show that pests in harvested grapes can be killed and optimum fruit quality maintained in the cool chain.

Enantiospecific Synthesis of Both Enantiomers of the Longtailed Mealybug Pheromone and Their Evaluation in a New Zealand Vineyard.

The irregular monoterpenoid sex pheromone of Pseudococcus longispinus and its enantiomer were prepared from the corresponding bornyl acetates. The use of readily accessible chiral starting materials and lactone-lactone rearrangement are the highlights of the present synthesis. The biological activities of the two enantiomers and racemic mixture were tested in a New Zealand vineyard. The (S)-(+)-enantiomer was significantly more attractive to P. longispinus males than the racemic mixture or the (R)-(-)-enantiomer.

FUMIGATION OF MEALYBUGS IN AUSTRALIAN TABLE GRAPES AND GRAPEFRUIT

Mealybug species such as long-tailed mealybug Pseudococcus longispinus (Targioni-Tozzetti) and citrus mealybug Planococcus citri (Risso) are sometimes present in Australian table grapes and grapefruits at harvest. Quarantine restrictions in some markets require fruit to be fumigated with methyl bromide at or above 21°C before shipment. Problems of phytotoxicity and reduced shelf life make this treatment unattractive. Alternative treatments, fumigation with ethyl formate and carbon dioxide for 2.5 h in export cartons in simulated cool down from 15 to 10°C were found to control mealybugs without damaging the produce. These treatments satisfy “generally regarded as safe” criteria and are suitable for use in grapes and grapefruits produced under organic certification.

The effect of mealybug Pseudococcus longispinus (Targioni Tozzetti) infestation of different density on physiological responses of Phalaenopsis × hybridum 'Innocence'.

Cultivated orchids are the most abundantly attacked by polyphagous mealybugs. This study documented how different density of mealybug Pseudococcus longispinus (Targioni Tozzetti) infestation is associated with a response of antioxidative systems of Phalaenopsis × hybridum 'Innocence'. The degree of cell damage, estimated by electrolyte leakage measurement and the level of thiobarbituric acid reactive substances (TBARS), the content of pigments as well as the activity of antioxidative enzymes and proline level, as measurements of stress and stress compensation in moth orchid were examined. The highest electrolyte leakage (E L) value among samples from colonized plants was found in the orchids from series III (50 individuals/plant), whereas the lowest in the plants from series II (20 individuals/plant). The TBARS content reached the highest level at the lowest number of feeding insects (series I). Peroxidase activity toward guaiacol was significantly increased in series I (5 individuals/plant). The highest catalase activity was recorded in plants colonized by the highest number of scale insects (series III). Whereas, the highest value of proline was in series II. The content of individual photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) in plant tissues did not vary significantly between control and colonized orchids. The results have not confirmed hypothesis that the increasing number of mealybugs occurring on plant enhanced plant physiological response. The degree of longtailed mealybug infestation on plants was positively correlated only with electrolyte leakage and catalase activity in leaf tissues.

Effects of Reduced-Risk Insecticides on Three Orchid Pests and Two Predacious Natural Enemies

The toxicity of 2 reduced-risk pesticides, 2% horticultural oil with 0.05% Silwet L-77 and Grandevo (Chromobacterium subtsugae Strain PRAA4-1T), to 2 predators: Metaseiulus occidentalis (Nesbitt) (Acari: Phytoseiidae) and Hemicheyletia wellsina DeLeon (Acari: Cheyletidae), and 3 orchid pests: the two-spotted spider mite Tetranychus urticae Koch (Prostigmata: Tetranychidae), the phalaenopsis mite, Tenuipalpus pacificus Baker (Acari: Tenuipalpidae), and the longtailed mealybug Pseudococcus longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) were tested. Grandevo did not kill either predator, and it failed to suppress populations of T. urticae and P. longispinus, but it reduced T. pacificus by 84%. The Silwet and horticultural oil mixture caused mortality of at least 82% in all 5 species tested.

Syntheses and Determination of Absolute Configurations and Biological Activities of the Enantiomers of the Longtailed Mealybug Pheromone

Preparation and assignment of absolute configurations to both enantiomers of the sex pheromone of the longtailed mealybug, an irregular monoterpenoid with extraordinary biological activity, has been completed. Comparison of the biological activities of both enantiomers and the racemate in field trials showed that the (S)-(+)-enantiomer was highly attractive to male mealybugs, strongly suggesting that female longtailed mealybugs produce this enantiomer. The (R)-(-)-enantiomer was benign, being neither attractive nor inhibitory.

Synthesis of a Sex Pheromone of the Longtailed Mealybug, Pseudococcus longispinus

The synthesis of a recently identified and highly active sex pheromone of the longtailed mealybug, Pseudococcus longispinus is reported. A concise synthetic route, use of the under explored Meyer–Schuster rearrangement, Claisen rearrangement, and ring-closing metathesis are the highlights of this work.

Intramolecular Carbolithiation as a Route to a Sterically Congested Cyclopentene: Synthesis of the Longtailed Mealybug Pheromone

A concise preparation of the pheromone secreted by the female longtailed mealybug [viz., 2-(1,5,5-trimethylcyclopent-2-en-1-yl)ethyl acetate] (1) is described. The key step in the synthesis of 1 involves 5-exo-trig ring closure of the vinyllithium derived from (Z)-1-iodo-4,4,5-trimethyl-1,5-hexadiene by lithium-iodine exchange.

Optimizing Metabolic Stress Disinfection and Disinfestation Components to Control <I>Pseudococcus longispinus</I>

Metabolic stress disinfection and disinfestation (MSDD) has been demonstrated to effectively control longtailed mealybug, Pseudococcus longispinus (Targioni Tozzetti). Standard components previously used for testing MSDD system included a 30-min physical phase of short cycles pressure changes followed by a 60-min chemical phase using ethanol vapor at 10 kPa. This study investigated the effect of varying the following MSDD components on mealybug mortality: duration of the physical and chemical phases, ethanol concentration, and extent of vacuum during the chemical phase. Mealybug mortality responses were analyzed, and the components were optimized using binary logistical regression to achieve 99% mortality of three life stages of the longtailed mealybug (adults, second- and third-instar nymphs and crawlers). Data indicated that the optimal components to achieve 99% mortality of all life stages were a 30-min physical phase and a 45-min chemical phase with 275 mg/liter ethanol at 30 kPa. Optimized components were obtained using binary logistical regression models. These optimized components yielded a 15-min reduction in total treatment time and a 20-kPa decrease in pressure during the chemical phase. Achievement of optimal insecticidal efficacy required all four MSDD components. Nevertheless, optimization and validation achieved 17 and 22% reductions in duration of treatment time and extent of vacuum, respectively.

Effect of Plant Characteristics and Within-Plant Distribution of Prey on Colonization Efficiency ofCryptolaemus montrouzieri(Coleoptera: Coccinellidae) Adults

Cryptolaemus montrouzieri(Coleoptera: Coccinellidae) has been widely used in classical and inundative biological control of mealybugs, including the long-tailed mealybug,Pseudococcus longispinus(Hemiptera: Pseudococcidae). This study was conducted to investigate colonization and establishment efficiency ofC. montrouzierito manageP. longispinuson three different ornamental plant species (Ficus elastica, Lilium longiflorum, andDieffenbachia seguine). Within-plant distribution pattern ofP. longispinusand the colonization ecology of adultC. montrouzieriwere investigated. Significantly moreP. longispinuswere found on the upper parts of the plants regardless of plant species, andC. montrouzieriadults discoveredP. longispinussignificantly faster when they were released on the top of the plants than on the bottom. Choice tests revealed thatC. montrouzieriadults preferred smallerP. longispinusnymphs. The implications for utilization ofC. montrouzierifor biological control of mealybugs on various ornamental plants are discussed.