Mealybug Research Articles

PCR-based quarantine procedure for the detection of cocoa swollen shoot virus

Cocoa (Theobroma cacao) is an economic tree crop which dominates the economy of most West African countries. Cocoa swollen shoot virus (CSSV) a badnavirus, transmitted by the mealy bug is a threat to the cocoa industry. Traditionally, indexing of cocoa trees for CSSV was usually carried out by budwood grafting donor materials onto disease-free Amelonado cocoa trees with symptoms of the virus expressed on the second or third leaf flushes. In CSSV budwood grafted transmissions involving genotypes other than Amelonado, symptoms may fail to develop on the leaves although the recipient trees may be infected. PCR/capillary electrophoresis was sensitive in detecting the CSSV and highlighted the disease well in advance of the appearance of visual symptoms. The design of the primer across the six published sequences of the cocoa genome capable of detecting all strains of the CSSV has the potential of improving the robustness of quarantine procedures for the international exchange and long term conservation of cocoa germplasm.

SURVEY OF MEALYBUGS (HEMIPTERA: PSEUDOCOCCIDAE) INFESTING GRAPES AND ORNAMENTAL PLANTS AND THEIR PARASITOIDS

Mealybugs comprise some of the worst pests of fruit and shade trees in many parts of the world especially In the tropical and subtropical oauntnes.There are numerous species of parasitoids that are associated with these pests. A field survey was conducted to determine the incidence of the mealybugs (Hemiptera: Pseudococddae) on grapes and ornamental plants and their associated parasitoids in. Six species of mealy bugs, Fernsia virgata (Cockerel!), Maconellicoccus hasutus (Green), Planococcus cilyi (Risso), Planocaccus flats •(Signoret), Pseudocoays longispinus (Targioni-Torzetti) and Sacchaticocrus sacchari (Cockerell) attaddng seven host plants including grape and ornamental plants and five associated parasitoids (Blepyrus insulans (Cameron), Anagyivs kamali Moursi, Gyranusoidea indica Shafee, Alam & Agarwal., Leptomastidea abnormis (Girault). Neoplatycerus kemtiats Trjapitin & Triapitsyn ) were observed. These results contribute to the definition of diversity of mealybugs and their parasitoids in Egypt.

A PRELIMINARY STUDY ON IMMATURE NUTFALL OF COCONUT WITH REFERENCE TO PEST DAMAGE

A PRELIMINARY STUDY ON IMMATURE NUTFALL OF COCONUT WITH REFERENCE TO PEST DAMAGE

Potential of extracts of the tropical plant Balanites aegyptiaca (L) Del. (Balanitaceae) to control the mealy bug, Maconellicoccus hirsutus (Homoptera: Pseudococcidae)

The effects of extracts of different parts of the perennial tropical plant Balanites aegyptiaca (L) Del., including various solvent extracts of roots, methanol extracts from leaves, fruits, flowers and roots, partially purified saponins obtained from its roots and a standard saponin were studied on the life cycle (adult longevity, number of eggs, crawlers, adults, weight of adults and % wax content) of a laboratory-reared parthenogenic line of the mealy bug, Maconellicoccus hirsutus (Homoptera: Pseudococcidae). Extracts derived from various parts of B. aegyptiaca (leaves, fruits, flowers, and roots in methanol) affected the life cycle of M. hirsutus with a methanol root extract being the most effective at a concentration of 500 μg ml −1. Partially purified saponin of B. aegyptiaca and the commercial bark saponin extract (Sigma) from Quillaja saponaria at a concentration of 500 μg ml −1 were effective in reducing the longevity of M. hirsutus. Significant reductions in oviposition by M. hirsutus were found for all the extracts at a concentration of 500 μg ml −1. Extracts also affected the number of emerging crawlers, number of adults as well as the weight and wax content of emerging adults. These studies suggest that B. aegyptiaca plant extracts and saponins can be useful botanical insecticides for the protection of crops from mealy bugs.

Host plants, geographical distribution, natural enemies and biological studies of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae)

The citrus mealy bug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae) is attacks many host plants including all orchard trees in Egypt. The aim of this work is to study the survey of host plants, geographical distribution and natural enemies of the citrus mealy bug, P.citri in Egypt as well as the biological studies of this pest on citrus, grape and guava. The results indicated that the citrus mealy bug infested 65 plant species belonging to 56 genera in 36 families and distributed in 20 governorates. Twelve species of parasitoids were collected and recorded one of them is new record. This is Leptomastix abnormis Girault (Hymenoptera: Encyrtidae). Also nine species of predators recorded here attacked P.citri. The results also observed the host plants and temperatures greatly influenced on the development of P. citri. The lowering of the temperature increased the dimension of the mealy bug and lengthened the developmental period. The results on citrus, guava and grape showed that the life cycle of P. citri at 30 o C were 21.4±2.45, 32.6±2.44 and 38.8±1.56 days, respectively.

Over seventy years of a viral disease of cocoa in Ghana: From researchers' perspective

Virus diseases have plagued cocoa (Theobroma cacao) production in West Africa for over seven decades. Principal among them is that caused by the cocoa swollen shoot virus (CSSV), which is endemic in Togo, Ghana and Nigeria, and more recently Cote d’Ivoire. The incidence of the disease in Ghana has led to the launch of the costliest and an over ambitious eradication control programme in the world. This review highlights the various research activities conducted mainly in Ghana that influenced the various control strategies as well as those that have the potential to influence future ones. Isolation of newly planted cocoa has been identified as an efficient method of reducing CSSV prevalence and spread in the field. Identification of mealybugs as vectors, the role of alternative host in the spread of the disease, the need for an urgent review of the eradication procedures, breeding specifically for resistance to CSSV as well as some biochemical and molecular biology studies are some of the points highlighted in this paper. The achievements and limitations made in these fields are duly emphasized. The way forward, however, will be to combine most of these strategies into a single or two integrated approaches to control cocoa swollen shoot virus disease (CSSVD). This will then be in tune with the suggestion that no single measure is adequate to solve the swollen shoot disease problem in Ghana, and the rest of West Africa. Key words: Eradication campaign, mild strain, cross-protection, CSSV, mealybugs, isolation, barriers, non-host crops, molecular biology, biochemistry.

Comparative Biology of Four Coccinellid Predators of Solenopsis Mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae)

The biology of four important species of coccinellid predators, viz. , Hyperaspis maindroni , Cryptolaemus montrouzieri , Nephus regularis and Scymnus coccivora associated with solenopsis mealybug, Phenacoccus solenopsis , infesting cotton and other crops of economic importance was studied in the laboratory @ 27±2°C and 65±5% RH. The overall developmental time (including adult longevity) of C. montrouzieri was found significantly longer (97.80±1.32 days) than the rest of the species which ranged between 58.60±2.38 and 72.40±2.11 days. Females generally had longer developmental durations than males, irrespective of the species. The females of C. montrouzieri laid an average of 510.00±9.73 eggs in their oviposition period of 62.20±3.14 and this was longer than the others. In all the species, female started egg laying in the 2 nd week of their adult life and reached the peak between 3 rd and 6 th weeks.

Virulence of Metarhizium anisopliae var. anisopliae to the larvae of Melanotus cribricollis (Coleoptera: Elateridae).

Toxicity of selected insecticides to papaya mealybug parasitoid, Acerophagus papayae (Noyes and Schauff) (Hymenoptera: Encyrtidae) was evaluated at 1, 3, 6 and 24h after treatment (HAT). Results showed that Thiamethoxam, Chlorpyriphos and Dichlorvos showed very high knock-down effect (100 % mortality) of A. papayae adults within 3 HAT. Fish Oil Rosin Soap (FORS) and Neem oil had very less detrimental effect on adult parasitoids by recording very low mortality percentage at 24 HAT. The residual toxicity data revealed that Thiamethoxam was the most persisting insecticide causing 26.67 per cent mortality of A. papayae even after 28 days after treatment (DAT). Neem oil and Fish Oil Rosin Soap became less or non toxic to adults of A. papayae at three DAT.

Ferrisia virgata, Soluble powder formulation (Sp) of Alum and Citric acid, Alternative Pesticides against Mealy Bugs

Ferrisia virgata, Soluble powder formulation (Sp) of Alum and Citric acid, Alternative Pesticides against Mealy Bugs

Occurrence of Papaya Mealybug, Paracoccus marginatus Williams and Granara De Willink (Hemiptera:Pseudococcidae), on Cotton

The papaya mealy bug, Paracoccus marginatus Williams and Granara de Willink, was recorded in severe form on cotton in Coimbatore in 2008-09. Infestation leads to drying of the sympodial branches and both Bt and non-Bt cotton hybrids have been observed to be infested. Spalgis epius (Westwood) (Lepidoptera: Lycaenidae) was recorded as a predator on P. marginatus infesting cotton and other hosts like papaya, silk cotton, subabul, Ixora sp., Crotons, Gliricidia sp. and Hibiscus sp. The larvae of S. epius were found to be voraciously feeding on the egg masses, nymphs and adults of the mealybugs.

Movento ®, an innovative ambimobile insecticide for sucking insect pest control in agriculture: Biological profile and field performance

The tetramic acid derivative spirotetramat (brand name Movento ®), has shown an outstanding performance against sucking insect pests in laboratory and greenhouse assays as well as in semi-field and field trials. The product acts as an inhibitor of lipid biosynthesis and affects juvenile stages with additional effects on adult fecundity. There is no cross-resistance to any other insecticide. After foliar application spirotetramat penetrates through the leaf cuticle and is translocated as spirotetramat-enol via xylem and phloem, up to growing shoots and down to roots. This full ambimobility or two-way systemicity (phloem and xylem transport) ensures the control of hidden and soil living sucking pests after foliar application and protects new shoots. The worldwide field development of spirotetramat in Bayer CropScience AG resulted in numerous uses against many species of whiteflies, aphids, scales (soft and armoured scales), mealy bugs, psyllids and selected thrips species in vegetables, cotton, soybean, pome and stone fruit, grapes, hop, citrus, nut trees and banana. The new mode of action renders spirotetramat as an excellent rotation partner with existing products for the management of aphid, whitefly and psyllid populations, which are frequently resistant to conventional insecticides. Moreover, only low adverse effects have been found on beneficial arthropods, which make the product suitable for modern integrated pest management (IPM) systems. These unique properties contribute to safeguarding the crop yield potential both in quality and quantity. In this paper, the new chemistry is presented, compared with standard insecticides and novel applications in IPM systems are discussed.

The insect pest complex of <i>Actinidia arguta</i> kiwifruit

The key insect pests of Actinidia arguta kiwifruit were determined by monitoring tagged fruit bunches for insects and insect damage in six orchard blocks from fruit set in November 2007 until harvest in February 2008 and by examining samples of picked fruit at harvest The proportion of fruit damaged by leafroller feeding increased throughout the entire growing season and live caterpillars were present on picked fruit at harvest Greenhouse thrips damage to fruit was noticeable from mid January Armoured scale insects and mealybugs were recorded on the fruit from December but most infestations occurred during the month prior to harvest Leafrollers and greenhouse thrips are the key production pests while leafrollers greedy scale and some mealybug species are potential quarantine species All three commercial A arguta cultivars grown in the Bay of Plenty are susceptible to the key pest species

Inhibition Studies of Cellulolytic Activities Isolated from Planococcus Citri

The study was performed to isolate the cellulolytic activities from a mealy bug Planococcus citri and to check their enzyme inhibition against leaf extract of Azdirachta indica and Buxus Sempervirens. Enzyme assay confirmed the presence of endoglucanase activity. Aqueous and non-aqueous fractions showed the maximum inhibition. Proteins containing fraction also reflected inhibition of activity that might lead to identification of some active peptides against cellulolytic activity.

Studies on mealy bug, Phenacoccus solenopsis Tinsley on transgenic cotton in North India

Fifty species of plants of taxonomic identity belonging to 20 families from field crops (4), fruits crops (5), ornamental crops (4), plantation crops (7), vegetable crops (9) and weed plants (21) were recorded as host of mealy bug. The studies conducted during 2007 and 2008 on its population dynamics revealed that the pest appeared on cotton immediately after sowing from other weed hosts and remained active throughout the cotton season. The peak infestation of P. solenopsis was recorded in August-September on cotton during both years. A low (1–10) to medium (10–20 ants/plant) grade population of ants were recorded on cotton plants infested withmealy bug. Seven predators and two parasitoids have been recorded feeding on mealy bug. Out of 14 insecticides tested profenofos @ 1250 ml, monocrotophos @ 1250 ml, chlorpyriphos @ 3000 ml, quinalphos @ 2000 ml, acephate @ 2000 g, thiodicarb @ 625 g and carbaryl WP @ 2500 g/ha were found effective as spot sprays.

Prediction of the hatch timing of the mealy bug Planococcus kraunhiae (Hemiptera: Pseudococcidae) in persimmon orchards using the effective accumulated temperature calculation simulation of the JPP-NET in Aichi

Prediction of the hatch timing of the mealy bug Planococcus kraunhiae (Hemiptera: Pseudococcidae) in persimmon orchards using the effective accumulated temperature calculation simulation of the JPP-NET in Aichi

Methodology for biological studies of mealybugs (Hemiptera: Pseudococcidae).

Several methodologies have been used in biological studies of mealybugs (Pseudococcidae) in the laboratory. The objective of this work was to compare three methodologies in order to establish a pattern for development studies. The development nymphal period and mortality of the citrus mealybug, Planococcus citri (Risso, 1813), was evaluated in PVC clip cages of 10 and 30 mm in diameter attached to leaves of coffee plants ( Coffea arabica L. cv. Acaia Cerrado), and on leaf sections placed over an agar film layer. Forty mealybug eggs were individually placed on the substrate and evaluated daily. The data were submitted to analysis of variance followed by the Test of Tukey (p≤ 0.005). Differences were detected in citrus mealybug nymphal development period and mortality depending on the used methodology. The shortest period and the lowest mortality were obtained using foliar sections maintained in agar-water which appears to be a viable methodology for mealybug studies in the laboratory. The excessive insect manipulation seems to be the main negative factor in mealybug development when using clip cages fixed to plant leaves.

About ovoviviparity in mealybugs (Homoptera: Coccinea: Pseudococcidae)

Ovoviviparity in the large family Pseudococcidae (mealybugs) is analysed for the first time. A preliminary list of 500 ovoviviparous species of 54 genera is given with figures for some species. A correlation between external morphology of mealybugs and mode of oviposition is discussed.

EVALUATION OF CERTAIN ORGANIC NUTRIENT SOURCES AGAINST MEALY BUG, COCCIDOHYSTRIX INSOLITUS (GREEN.) AND THE SPOTTED LEAF BEETLE, EPILACHNA VIGINTIOCTOPUNCTATA FAB. ON ASHWAGANDHA, WITHANIA SOMNIFERA DUNAL.

ABSTRACT Ashwagandha is considered as an important medicinal crop in Indian system of medicine. Ashwagandha suffers attack by several insect pests. The mealy bug, Coccidohystrix insolitus (Green.) and spotted leaf beetle, Epilachna vigintioctopunctata Fab. are found to be the key pests. Since Ashwagandha is a herbal medicine, application of synthetic chemicals leads accumulation of toxic residues. Field experiments were conducted with application of farmyard manure (FYM) (12.5 t/ha) + Azophos (2 kg/ha) + neem cake (1000 kg/ha) and need based foliar application of neem oil (3%) were found to be very effective in reducing the incidence of mealy bug and the damage of spotted leaf beetle.

POTENTIAL FOR ORGANIC MANGO PRODUCTION IN THE NORTHERN TERRITORY OF AUSTRALIA USING WEAVER ANTS, OECOPHYLLA SMARAGDINA, (HYMENOPTERA: FORMICIDAE)

High demand of organic mango in domestic and overseas markets has been increasing since the 1990s. However, insect pests are one of the main constraints limiting organic mango production in the Northern Territory. Previous work showed that weaver ants are effective in controlling the major mango insect pests, but they have not been extensively used because of three issues of concern by mango growers: (1) the ants may reduce mango yield due to their aggressive behaviour towards pollinators; (2) the ants farm mealy bugs that, in turn, may affect fruit quality; and (3) the ants annoy farm workers at harvest. Field experiments, together with long-term monitoring programs, were conducted in four non-spray or organic mango orchards from 2001 to 2003 in the Darwin area of Australia to address these issues. Data obtained from the four sites showed that compared with the treatment without weaver ants, the treatment with abundant weaver ants produced either similar or more fruit/tree/year, and 20.3%/tree/year more first class fruit. The overall profit /tree/year in the treatment with abundant weaver ants was 55.5% higher than the treatment without the ants. Putting fruit picked with a long-handled picking pole directly into a bucket filled with water and mango wash seems to be a useful way to avoid ant disturbance.

Extraction of Multi-Class Pesticide Residues in Mango Fruits (Mangiferae indica L.): Application of Pesticide Residues in Monitoring of Mangoes

Mango (Mangiferae indica L.) is an important exporthorticultural crop of India. Various insects and diseasesinfest the fruit especially in the fruiting season. The com-mon insect pests are mango leafhopper, mealy bug, leafwebber, inflorescence midge and fruit fly. The major lossof about 60% is due to leafhopper and mango leafhopper.These pests infest the mango at the floral and bud stage tofruit setting, tender leaves and small fruits. The crop pro-tection measures undertaken to control pest infestation in-volves spray of insecticides along with biological andcultural practices.India produces 65% of the world’s mango crop,9,000,000 MT, but with very little export. Although, Asiaaccounts for 75% world production, its dominance does nottranslate into international trade. The presence of pesticideremnants in mango lowers the export quality of mangofruits in the international market. To increase foreign trade,under the WTO regime, it is imperative to produce pesti-cide free mangoes.The insecticides commonly applied by the farmers areendosulfan, parathion methyl, chlorpyrifos, cypermethrinand fenvalerate. This paper presents a method for theestimation of the multi-class pesticides in mango and theirrecovery.Materials and MethodSolvents like acetone, dichloromethane, hexane (analyticalgrade), were distilled before use. Adsorbents neutral alu-mina and Florisil were activated before use. Pesticidestandards of methyl parathion, endosulfan, chlorpyrifos,cypermethrin and fenvalerate were of analytical gradequality. Gas Chromatogram instrumen-Shimadzu GC-17Afitted with an auto-sampler and ECD detector was used foranalysis. Other minor equipments required were rotaryevaporator and Waring blender, etc.Individual stock standard solutions (1,000 lg/mL) ofparathion methyl, endosulfan, chlorpyrifos, cypermethrinand fenvalerate were prepared in hexane (analytical grade).Working standard solutions of each pesticide was preparedby serial dilutions to 100 lg/mL, which was further dilutedto 0.1–10 lg/mL as per detector response. All the stocksolutions were stored at 4 C. Appropriate aliquot of indi-vidual pesticides solutions were taken and a mixture of fivepesticides of 100 lgmL