Dysmicoccus Brevipes Research Articles

Effect of pink pineapple mealybug hosts on Anagyrus ananatis Gahan size and progeny production

Abstract Studies were conducted to improve the colony production of Anagyrus ananatis Gahan (Hymenoptera: Encyrtidae) when reared on the pink pineapple mealybug (PPM), Dysmicoccus brevipes (Cockerell) (Hemiptera: Pseudococcidae). Parasitization of large PPM (>0.85 mm length) by A. ananatis resulted in an almost 3:1 ratio of female:male offspring. A strong positive correlation (r2 = 0.8935) was found between PPM weight and parasitoid size (i.e., length). Male parasitoids were not as food limited as females when the mealybug host was small. Despite the ability of A. ananatis to parasitize all host stages except crawlers, gravid adult female PPM produced larger parasitoids with higher fecundity. Allowing PPM to continue feeding on squash following parasitization produced larger parasitoids. However, for A. ananatis propagation it is more efficient to remove PPM from squash hosts and size them (via sieving) before exposing them to the parasitoid. Mealybugs >0.6 mg in weight and >0.5 mm in size can be used for parasitoid rearing to produce female A. ananatis (>1.4 mm length) that exhibit fecundities similar to those for A. ananatis that developed on PPM that fed on squash following parasitization (∼28 progeny per female). Furthermore, to maintain an A. ananatis female-biased sex ratio, PPM hosts >0.6 mm (medium size) would be preferable for use in parasitoid colony production. The length and width of PPM mummies were good predictors of the sex and body size of the parasitoid contained within, and may be potentially used as important indicators of parasitoid quality and fitness in a mass production system.

A new pest of tomato and other records of mealybugs (Hemiptera: Pseudococcidae) from Espírito Santo, Brazil

Three mealybug (Hemiptera: Pseudococcidae) plant pest species: Dysmicoccus boninsis (Kuwana), Phenacoccus solenopsis Tinsley, and Pseudococcus viburni (Signoret), are recorded for the first time in the state of Espírito Santo, Brazil. This is the first record of Phenacoccus solenopsis in Brazil, where it was found infesting tomato plants. The species Antonina graminis (Maskell), a common pest of Bermuda grass, and Dysmicoccus brevipes (Cockerell), a major pest of pineapple, also were encountered.

Diversity and Mealybug Transmissibility of Ampeloviruses in Pineapple.

Mealybug wilt of pineapple (MWP) is one of the most destructive diseases of pineapple (Ananas comosus) worldwide. At least one Ampelovirus species, Pineapple mealybug wilt associated virus-2 (PMWaV-2), and mealybug feeding are involved in the etiology of MWP. A previously undescribed Ampelovirus sharing highest homology with PMWaV-1 and a putative deletion mutant sharing highest homology with PMWaV-2 were detected with reverse transcription-polymerase chain reaction (RT-PCR) assays using degenerate primers. Results were verified with additional sequence information and by immunosorbent electron microscopy. Sequence homology between the virus tentatively designated PMWaV-3, and PMWaV-1 and PMWaV-2, decreases toward the N-terminal across the HSP70 homolog, small hydrophobic protein, and RNA-dependent RNA polymerase open reading frames (ORF). Putative PMWaV-3 could not be detected with four different monoclonal antibodies specific for PMWaV-1 and PMWaV-2. The potential deletion mutant spanning the N-terminal of the HSP70 region was obtained from a pineapple accession from Zaire maintained at the USDA-ARS National Clonal Germplasm Repository in Hawaii. Putative PMWaV-3, like PMWaV-1 and PMWaV-2, is transmissible separately or in combination with other PMWaVs by Dysmicoccus brevipes and D. neobrevipes mealybugs. Plants infected with PMWaV-3 that were continuously exposed to mealybugs did not develop symptoms of MWP in the absence of PMWaV-2. Specific RT-PCR assays were developed for detection of putative PMWaV-3 and the deletion mutant.

HUBUNGAN KUTU DOMPOLAN DYSMICOCCUS BREVIPES (CKLL.) (HOMOPTERA : PSEUDOCOCCIDAE) DAN SEMUT API SOLENOPSIS SP. (HYMENOPTERA: FORMICIDAE) PADA DUA CARA BERTANAM NENAS

Association of mealybug, Dysmicoccus brevipes (Ckll.) (Homoptera: Pseudococcidae) and fire ant, Solenopsis sp. (Hymenoptera: Formicidae) on two pineapple–planting patterns. A pineapple mealybug, Dysmicoccus brevipes (Ckll.) (Homoptera: Pseudococcidae) is an important insect pest in major pineapple growing areas. Its feeding activity causes damage on the pineapple plants and it can also transmit pineapple wilt virus. The mealybugs are often found in association with fire ants, Solenopsis sp. (Hymenoptera: Formicidae) that provide protection in exchange for the sweet honeydew liquid. The field study was conducted to determine the close association between mealybugs and fire ants on two plant row spacing (single and double row spacing) four different plant stages (3, 7, 11, and 17 months after planting). The results indicated that there was a significant correlation between the mealybugs and the fire ant on two pineapple-planting patterns, particularly on late growth periods (11, and 17 months after planting). In this field study, population of mealybugs on double row spacing were more abundant (ranging from 0 to 25.67 bugs/plant) compared with that on single row spacing which ranged 0 to 3.67 bugs/plant. Moreover, general mean of population density of mealybugs (14.53 bugs/plant) on double row was significantly higher than that on single row spacing (1.83 bugs/plant). In line with this mealybug-population development, mean numbers of fire ants caught on baited-sticky traps were ranged from 0 to 8.53 ants/trap on single row versus 0 to 23.57 ants/trap on double row spacing pattern. The general mean number of captured ants (12.73 ants/trap) on double row was significantly higher compared with that on single row spacing (5.55 ants/trap). It appears that the patterns of population densities of mealybugs are closely related to that of fire ants that act as attendant species on two pineapple row spacing.

Vector transmission of Banana streak virus in the screenhouse in Uganda

SummaryAlthough mealybug transmission of Banana streak virus.(BSV) by Planococcus citri and Saccharicoccus sacchar has been demonstrated elsewhere, these mealybugs have not been identified on bananas in Uganda and their role and that of other agents in BSV transmission is not well documented. Insect samples were collected from banana farms in sites with low, moderate and high BSV infections in Uganda. Subsequently, live mealybugs and aphids were again collected and used in acquisition, retention and transmission tests, and BSV diagnosed using TAS‐ELISA. Dysmicoccus brevipes (pineapple mealybug), S. sacchari (sugarcane mealybug) and Pentalonia nigronervosa (banana aphid) were the most abundant insect species from banana fields sampled. Abundance of D. brevipes was positively and significantly correlated with BSV incidence unlike that of. P. nigronervosa. Transmission studies in the screenhouse showed that mealybugs acquired BSV one day after feeding on virus sources and approached optimum acquisition after the third day. Pineapple and sugarcane mealybugs retained BSV up to 5 days from the day of transfer from the virus source. BSV was first detected in the recipient banana plants 4 wk after transmission using pineapple mealybug and 6 wk after inoculation using sugarcane mealybug. Under screenhouse conditions, both mealybugs therefore appear to transmit BSV semipersistently.

Suitability of Nine Mealybug Species (Homoptera: Pseudococcidae) as Hosts for the Parasitoid Anagyrus kamali (Hymenoptera: Encyrtidae)

The parasitoid Anagyrus kamali Moursi [Hymenoptera: Encyrtidae] has been recently introduced into the Caribbean as a biological control agent against the Hibiscus Mealybug, Maconellicoccus hirsutus Green [Homoptera: Pseudococcidae]. In order to understand host/parasitoid ecological interactions and optimize the mass-production system of this parasitoid, eight mealybug species (Planococcus citri (Risso), Planococcus halli Ezzat & McConnel, Dysmicoccus brevipes (Cockerell), Pseudococcus elisae Borchsenius, Saccharococcus sacchari (Cockerell), Puto barberii (Cockerell), Nipaecoccus nipae (Newstead), Plotococcus neotropicus (Williams & Granara de Willink)) common to Trinidad were tested to determine their potential as alternative hosts for the parasitoid. Susceptibility, preference and suitability tests were conducted. In addition to M. hirsutus (4.5 ± 2.04 hosts parasitized per female parasitoid in 30 min), Planococcus citri (1.1 ± 1.23 hosts parasitized) and Planoccocus halli (0.8 ± 1.41 hosts parasitized) were the only species parasitized. However, the parasitoid did not complete its development in the latter two hosts. Out of nine mealybug species, M. hirsutus was the only suitable host for the complete development of A. kamali progeny. This level of host specificity by A. kamali may prevent adverse effect to other Caribbean mealybug species.

Consumo alimentar de Chrysoperla externa sobre as diferentes fases de desenvolvimento de Dysmicoccus brevipes, em laboratório

Estudou-se o consumo e preferência alimentar de larvas de Chrysoperla externa Hagen, 1861 (Neuroptera: Chrysopidae) em laboratório à temperatura de 25±2°C, 70±10% UR e 12 horas de fotofase, utilizando como presa a cochonilha-do-abacaxi (Dysmicoccus brevipes Cockerell, 1893, Hemiptera: Pseudococcidae). Durante a fase larval do predador foram consumidas, em média, 70, 50 e 15,8 cochonilhas do primeiro, segundo e terceiro ínstar, respectivamente, e 10 fêmeas adultas, num total de 145,8 indivíduos. Do número total de cochonilhas, 51% foram consumidos durante o terceiro ínstar do predador. O alto número de cochonilhas consumido demonstra que a C. externa apresenta potencial para ser utilizada no controle biológico da cochonilha D. brevipes.

Impact of Pheidole megacephala (F.) (Hymenoptera: Formicidae) on the Biological Control of Dysmicoccus brevipes (Cockerell) (Homoptera: Pseudococcidae)

Two field experiments designed as the biological check method (interference) and the paired-cage technique (exclusion) were used to evaluate the effectiveness of natural enemies in maintaining low densities of the pink pineapple mealybug, Dysmicoccus brevipes (Cockerell), in pineapple plantings in Hawaii. In the biological check method, the treatments were ant-free plots and ant-infested plots. The numbers of D. brevipes, parasitized mealybugs, and immature and adult predators on the aerial parts of the plants were recorded. Results in the biological check method suggested that Anagyrus ananatis Gahan was responsible for the decline of D. brevipes densities in the absence of ants. In a second study combining the paired-cage technique and the biological check method, the treatments included mealybug-infested potted pineapple plants with no ants or mealybug natural enemies, ants but no natural enemies, natural enemies but no ants, and ants and natural enemies. This experiment showed that in the absence of the big-headed ant, Pheidole megacephala (F.), D. brevipes densities were greatly reduced by natural enemies and probably by the lack of sanitation or other ant activity. A laboratory study also was conducted to evaluate the impact of P. megacephala on oviposition and predation by A. ananatis and the coccinellid Nephus bilucernarius Mulsant, respectively. These laboratory studies indicated that P. megacephala significantly decreased mealybug mortality induced by A. ananatis and N. bilucernarius adults via interference with natural enemy searching behavior. r 1999 Academic Press

Survey of the natural enemies of Dysmicoccus mealybugs on pineapple in Hawaii

Surveys for mealybugs, associated natural enemies and ants were conducted in abandoned pineapple fields on the Hawaiian islands of Oahu and Maui from July 1992 to November 1993. Whole plant samples were taken, and mealybugs and ants found were identified. Mealybug-infested plant parts were isolated and held until natural enemies emerged from parasitized host material. At sample sites where only Dysmicoccus brevipes was present, its densities ranged from a mean of 23 to 157 mealybugs per plant, while in areas with mixed populations of this mealybug and Dysmicoccus neobrevipes Beardsley, densities ranged from a mean of 23 to 118 mealybugs per plant. Ants were present at all sample sites and on all dates. Pheidole megacephala (F.) was the most common ant species found. Anagyrus ananatis Gahan was the most common parasitoid reared. However, it attacked only D. brevipes, the dominant mealybug in the pineapple fields surveyed. Percent parasitization of D. brevipes by A. ananatis in the presence of ants ranged from 0.3 to 9.9%. Percent parasitization of D. brevipes and D. neobrevipes per plant by Euryrhopalus propinquus Kerrich ranged from 0.05 to 2.2%. Mean densities of the predators Lobodiplosis pseudococci (Felt), Nephus bilucernarius Mulsant and Sticholotis ruficeps Weise ranged from 0.05 to 5.75, 0.1 to 1.8, and 0.05 to 0.2 individuals per plant, respectively.

Transmission of Pineapple Mealybug Wilt-Associated Virus by Two Species of Mealybug (Dysmicoccus spp.)

ABSTRACT Closterovirus-like particles associated with mealybug wilt of pineapple were acquired and transmitted by the pink pineapple mealybug, Dysmicoccus brevipes, and the gray pineapple mealybug, D. neobrevipes. Mealybugs acquired pineapple mealybug wilt-associated virus (PMWaV) from infected pineapple plants or detached leaves. The virus was detected in plants by tissue blot immunoassay and confirmed by immunosorbent electron microscopy. Plants exposed to mealybugs reared on PMWaV-free pineapple tissue remained uninfected. The presence of ants was correlated with an increased rate of virus spread when caged with D. brevipes. All stages of D. neobrevipes acquired PMWaV, although vector efficiency decreased significantly in older adult females. The probability of a single third-instar immature transmitting the virus was 0.04. Both species of mealybug acquired and transmitted PMWaV from infected pineapple material that had been clonally propagated for decades, and both species acquired PMWaV from sources previously infected with the virus by the other mealybug species.

Dispersal of Plant Pests into the Virgin Islands

On 26 October 1990, Greg Mayer, Tina Kuklenski, and Scott Miller sampled invertebrates from a large shipment (an entire barge) of potted plants being unloaded at Guana Island, British Virgin Islands (BVI). Becker & Miller (1992) provide background on Guana Island. The plants, including many specimens of several species of palms, were being imported from nurseries in southern Florida for landscaping. The importers had apparently met all BVI regulations and had checked in with government authorities in Tortola before the barge proceeded to Guana Island. The shipment was infested with large numbers of insects and snails, most of which have been identified as follows. A millipede, an isopod, and several beetle larvae were not identified. Cockroach (Blattodea: Blaberidae) Pycnoscelus surinamensis (Linnaeus), Surinam cockroach Mealybug (Homoptera: Pseudococcidae) Dysmicoccus brevipes (Cockerell), pineapple mealybug Ants (Hymenoptera: Formicidae) Brachymyrmex obscurior Forel Hypoponera opaciceps (Mayr) Odontomachus ruginodis Wheeler Paratrechina longicornis (Latreille), crazy ant Paratrechina pubens (Forel) Pheidole morerens Wheeler Snails (Mollusca) Lamellaxis gracilis (Hutton) Polygyra cf. P. cereolus (Muhlfeld) Praticolella griseola (Pfeiffer) Succinea cf. S. luteola floridana Pilsbry Although some of these species are native to the Puerto Rican Bank, most are immigrant species that are now widespread in the Caribbean region, including southern Florida (Godan 1983, Roth 1994). Most are known from the Puerto Rican Bank (Wolcott 1950-1951). Several major agricultural pests are included, such as those with common names listed. The presence of this many invertebrates on this shipment indicates the ease of dispersal of agricultural pests. Non-indigenous pests are a major problem for North American agriculture (Dowell & Krass 1992, Sailer 1978, 1983, U.S Congress 1993). In addition to being agricultural pests, non-indigenous insects and snails appear to be the primary cause of extinction for native invertebrates on islands (e.g., Howarth 1990, Howarth & Ramsay 1991). Vectors of human disease, such as Aedes albopictus (Skuse) (Asian tiger mosquito), can also be spread by commerce (e.g., Francy et al. 1990, Mitchell et al. 1992). The recent spread of two giant African snails, Achatina fulica Bowditch and Limicolaria aurora (Jay), to Martinique is a stark example of the problem of continued pest dispersal (Mead & Palcy 1992). Given the threat that non-indigenous insects and snails present to agriculture, human health, and conservation management, and potential economic consequences of such introductions, island governments should create and implement policies for the

Arthropods Associated with Bromelia hemisphaerica (Bromeliales: Bromeliaceae) in Morelos, Mexico

A survey was conducted of the arthropod fauna associated with Bromelia hemisphaerica Lamarck (Bromeliaceae) at Yautepec, Morelos, Mexico. In this survey, conducted from January to September 1989, 40.3 percent of the species represented in the collections were predatory, belonging to the orders Araneae, Acarina (Parasitiformes and Acariformes), Hemiptera, Coleoptera and Hymenoptera. Herbivorous species accounted for 16.4 percent of the total species collected. Among these were Ferrisia virgata (Cockerell) and Dysmicoccus brevipes (Cockerell), which might become pests when these plants are cultivated in monoculture.

Pineapple: Chemical Control of Mealybug and Associated Ants in Guyana12

Ants (Solenopsis sp. and Araucomyrmex sp.) tend the pineapple mealybug, Dysmicoccus brevipes (Cockerell), on pineapple in sandy soils and cause heavy infestations. Aldrin spray was not very effective against Solenopsis sp. but was effective against Araucomyrmex sp. Powdered skimmed milk plus wheaten flour and wheat middling were attractive to Solenopsis sp. and Araucomyrmex sp., respectively. Heptachlor was superior to mirex as a toxicant in baits for both ant species. Application of bait to nests destroyed almost all ant colonies. With the elimination of ant Solenopsis sp., sand shelters made by the ant over mealybug colonies crumbled, sooty mold developed in mealybug colonies, and ca. 75% of the mealybugs died. Forty-three insecticides were compared in the laboratory for toxicity to the mealybug. For disinfestation of planting material by dipping slips in insecticidal fluid, omethoate was best with LC99.9 and LC99.99 values of 0.0052 and 0.0135%, respectively. For control of residual population of mealybug on field plants after control of ants, 37 mg AI phoxim/plant as 0.07% emulsion spray, 62.5 mg AI phorate/plant as 0.625% emulsion poured in whorl while it rained, or 48 mg AI phorate/plant as 3% granules placed in whorl and side leaves proved better than other treatments tested. Because of concern about safety of phorate, phoxim spray is recommended for mealybug control.

Control de <i>Dysmicoccus brevipes</i> (hemiptera: pseudococcidae), en el fruto de piña, san carlos, Costa Rica

Se evaluaron 6 productos para el control de Dysmicoccus brevipes en piña (Ananas comosus). El ensayo de laboratorio se realizó en el Laboratorio de Biocontroladores de la empresa BioEco Natural S.A., ubicada en Aguas Zarcas, San Carlos, mientras que los ensayos de campo se realizaron en una plantación comercial de piña, en Venecia de San Carlos. En el laboratorio se evaluó Beauveria bassiana (4,0 x 1010 esporas.g-1); Metarhizium anisopliae (1,0 x 1010 esporas.g-1); una mezcla de ambos hongos (0,5 g + 0,5 g.l-1 de agua destilada, de 4,0 x 1010 esporas.g-1 + 1,0 x 1010 esporas.g-1); un jabón líquido de sales potá- sicas, “Goyca”® (7 ml.l-1); el extracto botánico (Biorep®) (mezcla de chile picante, ajo, cebolla, mostaza y gavilana) (7 ml.l-1); y agua destilada como testigo. Los resultados más promisorios fueron con el extracto botánico y el jabón líqui- do, los que causaron una mortalidad más rápida. Los tratamientos evaluados en la plantación comercial de piña, var. MD-2, fueron los mis- mos, a excepción del testigo en donde se utilizó los productos utilizados de forma comercial en la finca: Diazinon® 60 EC (diazinon) (0,5 ml.l-1) y Sevin® 80 WP (carbaril) (1 kg.ha-1). El extrac- to botánico resultó en la menor incidencia de cochinillas (X=6,4), < al testigo (X=10,8), < elGoyca® (X=13,7), < M. anisopliae (X=44,4), < B. bassiana (X=45,1), y <B.b+M.a (X=45,8). No se encontraron diferencias en la longitud y circunferencia de los frutos por efecto de los productos aplicados. El costo por héctarea fue similar entre tratamientos, aunque el menor fue el testigo (18.800 colones), y mayor en el extracto botánico (29.700 colones). Los resultados muestran como mejor opción el uso del jabón líquido para el control de D. brevipes.

A Study of Mealybug Populations (Dysmicoccus brevipes (Ckl.)) in an Ant-Free Field1

A quantitative study of mealybug populations (Dysmicoccus (Pseudococcus) brevipes (CkI.)) was made in a 24-acre pineapple field which was kept free of ants. Leaf colonies of mealybugs remained small whether the plot was sprayed or not and fluctuations were of the same order. Subterranean colonies developed in the absence of ants and the frequency and size of these colonies were roughly correlated with the incidence of scattered wilted plants. This incidence, however, was greatly reduced in strips previously occupied by field roads where plant growth was better.