Mealybug Populations Research Articles

Effectiveness of Neem Seed Extract Formulation (Azadirachta Indica) and Bitung (Barringtonia asiatica) against Mealybug Papaya (Paracoccus marginatus) (Hemiptera: Pseudococcidae)

The papaya mealybug (Paracoccus marginatus) Williams & Granara de Wilink (Hemiptera: Pseudococcidae) is a main pest of papaya plants. Attacks by these pests can cause plants failed to produce the fruit and even to death. The usual control technique used by farmers is the use of synthetic pesticides that have a negative impact on human health and the environment. The alternative to control using botanical insecticides is a good solution to control the population of P. marginatus. The purpose of this study is to know the effect of neem seed oil formulation and bitung to know which treatments with concentrations are most effective in reducing the population density of papaya mealybug pests. The experiment took place in Rejasari Village, Langensari Subdistrict, Banjar City, West Java, from March 2021 to July 2021. Experiment using the Randomized Block Design consisted of ten treatments with three replications. The results were obtained that a formulation of bitung 3% could suppress the densities of papaya mealybug ( P. marginatus) populations at 65%. The average weight of the resulting papaya contained a 3% formulation of bitung found at 9.8 kg/tree. botanical pesticides of bitung oil 3% can be used instead of synthetic pesticides to control the population of P.marginatus.

IDENTIFIKASI SERANGAN HAMA KUTU PUTIH (Pseudococcus citri) PADA BUAH KAKAO (Theobroma cacao L.) DAN UPAYA MENEKAN SERANGAN DENGAN CENDAWAN Beauveria bassiana

The purpose of this study was to determine the population of mealybugs before and after application of the fungus Beauveria bassiana, to determine the mortality of mealybugs after application of the fungus Beauveria bassiana, and to determine the appropriate dose of the fungus Beauveria bassiana to control mealybugs. This research was conducted from early April to July 2021 and took place in the community garden in Teluk Kedondong Village, RT 22, Sempaja Utara Village, North Samarinda District. The study used purposive sampling method with 4 doses of Beauveria bassiana repeated 5 times (B0 = Control), (B1 = 5 g/ Liter of water), (B2 = 10 g/ Liter of water), (B3 = 15 g/ Liter of water). ). Based on the results of the study, the identification of the attack rate of mealybugs (Pseudococcus citri) on cocoa (Theobroma cacao L.) and efforts to suppress its attack with the fungus Beauveria bassiana, it can be concluded that: After application of the fungus Beauveria bassiana the population of mealybugs showed a decrease. The mortality of mealybugs after application of the fungus Beauveria bassiana was 100%. The best and most effective dose in suppressing the attack of mealybugs is 5 g/liter of water. To suppress the attack of mealybugs, it is recommended to use a dose of 5 g/liter of water by spraying it on the fruit and then wrapping it in plastic so that the fungus can be more effective.

Spatial Roguing Reduces the Incidence of Leafroll Disease and Curtails Its Spread in a Finger Lakes Cabernet franc Vineyard

<h3>Abstract</h3> Leafroll is one of the most economically important viral diseases of grapevines worldwide. Grapevine leafroll-associated virus 1 (GLRaV-1) and grapevine leafroll-associated virus 3 (GLRaV-3) are prevalent in New York vineyards in which low-density grape mealybug populations reside. A five-year experiment was performed in a commercial ‘Cabernet franc’ vineyard in the Finger Lakes region of New York to test the influence of spatial roguing, i.e., the elimination of virus-infected vines and their two immediate within-row neighbors on each side, on the annual incidence of GLRaV-1 and GLRaV-3. In a second treatment, spatial roguing was combined with insecticides. Vines eliminated in both spatial roguing treatments were replaced by clean vines derived from virus-tested stocks. The objective of this study was to reduce temporal virus incidence to less than 1% over two consecutive years and limit virus spread. In both spatial roguing treatments, virus incidence was reduced from 5% in 2016 to less than 1% in 2020-2021. Among vines in the insecticide-free, non-rogued control treatment, virus incidence increased from 5% to 16% from 2016 to 2021. Insecticides applied in 2016-2021 helped significantly reduce grape mealybug populations to near zero annually, while populations in the untreated control vines were 57 to 257-fold higher during the same period. However, insecticides contributed relatively little to limit the number of newly infected vines. Together, these findings highlight the salient contribution of roguing to an overall leafroll disease management response in a vineyard with low disease incidence and low grape mealybug abundance. To our knowledge, this is the first report on the effectiveness of spatial roguing at reducing the annual incidence of leafroll disease in a vineyard.

Effect of neem derivatives (Azacdirachta indica) on the mango mealybug (Rastrococcus invadens) for biological control

Pest insects are a major constraint on fruit production in Senegal. In order to find an alternative to the chemical control of these pests, the insecticidal effect of neem derivatives (Azadirachta indica) formulated at different doses on the mango mealybug (Rastrococcus invadens) was studied. The powders obtained from the different parts of the neem were mixed with distilled water in different proportions, namely for 100ml 0g (control), 1g, 2g, 4g, 8g, 16g, 32g, 64g and 124g. The whole, consisting of water and powders of the different parts of neem, was homogenized. For each treatment, 5 repetitions were made over 5 days. The results obtained show that neem significantly reduced the populations of mealybug on the mango tree. The results also showed that neem is a very effective insecticide against these pests. This effectiveness is all the more important with almond derivatives (100% mortality at a dose of 32g per 100ml) compared to other neem derivatives.

Efficacy of biorational insecticides for the management of mealybug, Maconellicoccus hirsutus (Green) and spiralling whitefly, Aleurodicus disperses (Russel) and their safety to coccinellid beetles on guava

Field experiment on effectiveness of different biorational insecticides against mealybug (Maconellicoccus hirsutus Green) and spiralling whitefly (Aleurodicus disperses Russel) and their safety to natural enemies in guava were carried out at Experimental Farm, Division of Entomology and Nematology, IIHR, Bangalore, India during 2015-16. All the treatments were significantly superior over untreated check. Results indicated that the maximum reduction of mealybug population was recorded in the treatment of organic salt 30 WS @ 5 ml/l (2.32 mealy bugs/three shoots) followed by spinosad 45 SC @ 0.2 ml/l (2.45 mealy bugs/three shoots) after first and second spray respectively. Whereas less population of spiralling whitefly was recorded in spinosad treated plot (2.06 spiralling whiteflies/three leaves). Safety of natural enemy’s concern dimethoate 30 EC @1.6 ml/l, azadirachtin 10000 ppm @1 ml/l and Neem soap @ 10 g/l were found to be more harmful to coccinellid beetles and recorded very less beetle population, while Organic salt 30 WS @ 4 ml/l, L. lecanii @ 2 g/l and spinosad 45 SC @ 0.2 ml/l were the safest chemicals

Study on Ferrisia virgata and Planococcus minor as vectors of mottle disease in black pepper

Two species of mealybug, Ferrisia virgata and Planococcus minor were previously reported as vectors of Piper yellow mottle virus (PYMoV), the causal agent of mottle disease in black pepper (Piper nigrum). Several activities were performed to study the PYMoV transmission through F. virgata and Pl. minor, involving transmission experiment in ISMCRI greenhouse (Bogor, West Java), field observation of mealybugs, and mottle disease incidence at ISMCRI field station (Sukabumi, West Java). The result showed that the transmission rate of PYMoV through F. virgata and Pl. minor in black pepper reached 40.00 and 46.67%, respectively. Field temperature >33 °C, light intensity >700.00 lux, wind speed <1.10 m/s, and rainfall <80 mm/month were recorded during the occurrence of a peak population of mealybugs. Mealybugs population in the field was affected by insecticide application. Its population was lower in a block with insecticide spraying than in a block without insecticide spraying. Furthermore, mottle disease incidence was correlated with the population level of mealybugs. Based on PCR detection, the frequency of viruliferous mealybugs did not differ in a block with or without insecticide spraying, i.e., 6/39 and 6/37, respectively. This indicated that other factors than insect vectors might play an important role in disease spread.

Impact of weather parameters on seasonal incidence of black pepper root Mealybug, Formicococcus polysperma Williams under hill zone of Karnataka

The present investigation was undertaken to find the impact of weather factors on seasonal incidence of sucking pest of black pepper under field conditions during 2017-18 & 2018-19. The incidence of root Mealybug population 5.36 and 6.93 colonies per 15 cm root length was observed during 2017-18 & 2018-19, respectively, with an average population of 6.14. the incidence was noticed throughout the year and reached peak by 40th standard week (18.80 & 8.10 mealy bug colonies/15cm root length) (i.e. October & November) confirming the infestation during post rainy season coinciding drier months with relative humidity (84%) in soil favouring the pest population and lowest population in March (2.40). The per cent infestation of pepper vines ranged from 21 to 48 per cent with an average per cent damage of 31.79%. There was a strong positive correlation was observed between rainfall, relative humidity, maximum temperature and root mealy bug population.

Nursery Management of Two Major Below-Ground Feeding Plant Pests: Root Mealybug,Rhizoecus sp. and Rice Root Aphid,Rhopalosiphum rufiabdominalis(Sasaki) (Hemiptera: Pseudococcidae and Aphididae)

AbstractRoot mealybug (Rhizoecus sp.) and rice root aphid (Rhopalosiphum rufibdominalis) are below-ground feeding insects that are difficult to control and have become major pests as production of their host plants has grown. Field trials were designed to investigate the impact new insecticides and biopesticides have on root mealybugs and rice root aphids. In our first three trials, we investigated the effects of biopesticides, entomopathogenic nematodes or fungi on reflexed stonecrop (Sedum rupestre) and stonecrop (S. montanum) against root mealybug. We found that flupyradifurone (Altus), flonicamid (Aria), chlorantraniliprole (Acelepryn), pymetrozine (Endeavor), Beauveria bassiana (Mycotrol), Chromobacterium subtsugae (Grandevo), Burkholderia spp. strain A396 (Venerate), cyantraniliprole (Mainspring) and Steinernema carpocapsae (Millenium) significantly reduced root mealybug populations compared to nontreated controls when applied as drenches in a curative manner. In our fourth trial, we evaluated biopesticides and Beauveria bassiana, on rice root aphid feeding on common rush (Juncus effusus) roots. Results showed pymetrozine significantly reduced populations as early as 14 days after treatment and continued to reduce their population throughout the remainder of the trial. However, chlorantraniliprole, cyantraniliprole, Beauveria bassiana, M-306 and MBI-203 did not significantly reduce rice root aphid populations until 28 days after initial application. Predator activity on root balls of Juncus effusus plants was also noted during the trials and may provide an integrated pest management (IPM) approach in controlling populations.Index words: reflexed stonecrop, Sedum rupestre L, stonecrop, Sedum montanum Song. &amp; Perr, common rush, Juncus effuses L, Beauveria bassiana, Mycotrol, Steinernema carpocapsae, Millenium, reduced-risk pesticides, Chromobacterium subtsugae (Grandevo), flupyradifurone, Altus, flonicamid, Aria, chlorantraniliprole, Acelepryn, pymetrozine, Endeavor, Burkholderia spp. strain A396, Venerate, cyantraniliprole, Mainspring, M-306, MBI-203.Chemicals used in this study: flupyradifurone (Altus); flonicamid (Aria); chlorantraniliprole (Acelepryn); cyantraniliprole (Mainspring); pyrometrozine (Endeavor); Burkholderia spp. strain 396 (Venerate); Chromobacterium subtsugae (Grandevo); Beauveria bassiana (Mycotrol); AMBI-203 WDG – 30% Chromobacterium subtsugae strain PRAA4-1T cells and spent fermentation media. EPA registration number 84059-27; MBI-206 EP – 94.46% Heat-killed Burkholderia spp. strain A396 cells and spent fermentation media. EPA registration number 84059-14; MBI-203 SC2 – 98% Chromobacterium subtsugae strain PRAA4-1T cells and spent fermentation media. Experimental; MBI-306 SC1 - 94.46% non-viable Burkholderia spp. strain A396 cells and spent fermentation media. Experimental.Species used in this study: Root mealybug, Rhizoecus sp; Rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki); reflexed stonecrop, Sedum rupestre; stonecrop, Sedum montanum; common rush, Juncus effusus.

POPULASI DAN TINGKAT SERANGAN HAMA KUTU PUTIH Dysmicoccus brevipes (Hemiptera : Pseudociccidae) PADA TANAMAN JAHE (Zingiber officinalle Rosc) DI DESA NUAMURI KECAMATAN KELIMUTU

This study aims to determine the population and level of attack of mealybug pests on ginger plants during harvesting in Nuamuri Village, Kelimutu District, Ende Regency. This research was carried out from February 2020 to July 2020, in Detubewa village, Nuamaro village and Nuamuri village. Observations were made by directly counting pests and damaged and attacked rhizomes, using the path method. Data analysis used is data obtained from the location of observations in tabulation based on the results of direct observations in the field. What was observed was the population and attack rate of each affected ginger planting location. The results showed that during the observation, the highest population of mealybugs was found in Detubewa village with 2,645 heads and the lowest value was in Nuamaro village, namely 2,127 heads, the highest pest population after Detubewa village was village Nuamuri with 2,478 individuals. Meanwhile, the attack rate and presentation of very heavy attacks were in Detubewa village by 84%, and heavy attacks in Nuamuri village at 66% and Nuamaro village at 68%.

Efficacy of Selected Insecticides in Reducing Rhodesgrass Mealybug (Hemiptera: Pseudococcidae) Density on Golf Course Putting Greens

Rhodesgrass mealybug, Antonina graminis (Maskell) (Hemiptera: Pseudococcidae), has long been a pest of warm-season grass species used for turf and hay. This species is benefiting from a recent resurgence as a pest of golf course putting greens. No efficacy information is currently available to aid in selecting insecticides for the management of rhodesgrass mealybug. This three-year study evaluated the efficacy of seven active ingredients (acephate, alpha-cypermethrin, cyantraniliprole, dinotefuran, flupyradifurone, imidacloprid, and thiamethoxam) applied at several concentrations to golf course putting greens in Georgia and South Carolina, United States. The goal of this study was to identify the most effective insecticides for rhodesgrass mealybug management. Acephate, flupyradifurone, imidacloprid and thiamethoxam achieved greater and more consistent reduction in rhodesgrass mealybug abundance than other insecticides in multiple experiments. Based on our results, long-term suppression of mealybug populations could only be achieved through repeated applications of these insecticides targeting crawlers or an integrated pest management program that complement chemical control. There are needs to further improve management efficacy against rhodesgrass mealybugs by identifying additional effective insecticides of different modes of action to complement acephate, flupyradifurone, imidacloprid and thiamethoxam, and methods by which the efficacy of these insecticides could be further improved.

Spray Volume and Frequency Impacts on Insecticide Efficacy Against the Citrus Mealybug (Hemiptera: Pseudococcidae) on Coleus under Greenhouse Conditions

Abstract The citrus mealybug Planococcus citri (Risso) (Hemiptera: Pseudococcidae) is a major insect pest of greenhouse-grown horticultural crops. The citrus mealybug causes direct damage by feeding on plant leaves, stems, flowers, and fruits, which can lead to substantial economic losses. Consequently, insecticides are used to suppress citrus mealybug populations in greenhouse production systems. However, application factors may influence the efficacy of insecticides in suppressing citrus mealybug populations. Therefore, experiments were conducted under greenhouse conditions to determine the effect of spray volume and application frequency on insecticide efficacy against the citrus mealybug feeding on coleus, Solenostemon scutellarioides (L.) Codd, plants. Four spray volumes (15, 25, 50, and 75 mL), 2 application frequencies (1 or 2 applications), and 3 insecticides (acetamiprid [TriStar®], flonicamid [Aria®], and cyfluthrin [Decathlon®]), each with a different mode of action, were tested. Based on mean percent citrus mealybug mortality, acetamiprid was more effective against citrus mealybugs than flonicamid or cyfluthrin. In the spray volume experiments, acetamiprid applied at 75 mL to each plant resulted in a mean percent citrus mealybug mortality of over 70%. In contrast, flonicamid and cyfluthrin resulted in less than 50% mean citrus mealybug mortality across all experiments. In the application frequency experiments, two spray applications did not result in a significantly higher mean citrus mealybug mortality than one spray application. Our study emphasizes the importance of spray volume and application frequency when using insecticides to suppress citrus mealybug populations.

Antibiotic susceptibility of endosymbionts of papaya mealybug Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae)

Aim: The present study aimed to select a powerful tool to evaluate the antibiotic susceptibility of endosymbionts of papaya mealybug. Methodology: Antibiotic Ofloxacin (0.25µg) was used to disrupt the endosymbionts of mealybug. The antibiotic susceptibility of endosymbionts was studied by conventional method; isolation of symbionts in Luria Bertani Agar and Nutrient Agar and also metagenomic analysis was conducted using nanopore sequencing of 16S rRNA gene. Results: Molecular identification of isolates showed Gram-positive bacteria i.e., Bacillus cluasii, B. altitudinis, B. siamensis and Gram-negative bacteria, i.e., Serratia marcescens and Stenotrophomonas maltophilia. Metagenomic analysis using 16S amplicon sequencing resulted in identification of Candidatus Tremblaya Princeps (55%) was more abundant followed by Candidatus Mikella endobia (23%) in untreated mealybug population. Their population was reduced to 7% in Candidatus Tremblaya Princeps and below 1% in Candidatus Mikella endobia. Interpretation: The current study confirms that the metagenomic analysis acts as a power lens to evaluate the antibiotic elimination of endosymbionts, hence with this method future works on developing aposymbiotic mealybugs can be done.

Field Bio-Efficacy of “Brigade-BL” (Beauveria bassiana) an Entomopathogenic Fungi for the Management of Mealy Bugs on Thompson Seedless Grapes

A field bio-efficacy of Brigade-BL (Beauveria bassiana) an entomopathogenic fungi was evaluated against mealy bugs (Meconellicoccus hirsutus) on Thompson Seedless grapes at National Research Centre on Grapes, Manjri, Pune during 2014-15. The experiment was conducted in RBD with five replications on foundation pruning and fruit pruning. Results obtained revealed that application of Brigade-BL @ 5.0 ml/L with two sprayings resulted in reduction of mealy bug colonies upto 67.82% in foundation pruning as compared to control. Likewise, at fruiting pruning, after fifth spray of Brigade-BL @ 5.0 ml/L recorded 75.68% reduction in mealy bug population and increase in fruit yield of 92.44% over control. Similarly, there was no any abnormality and phytotoxic effect observed by spraying Brigade-BL on grapevines. Likewise, Brigade-BL was found compatible with Buprofezin 25 SC chemical insecticide.

Development of a Mating Disruption Program for a Mealybug, Planococcus ficus, in Vineyards.

Simple SummaryThe vine mealybug is a key insect pest of vineyards that currently is controlled by one or more insecticide applications per season. Here, we sought to develop a more sustainable control tool by using the mealybug’s sex pheromone to reduce mating and thereby lower pest damage. The mature female mealybug emits a sex pheromone that the winged adult male uses to find and mate with females. Synthetically produced sex pheromone, specific to the vine mealybug, was enclosed in commercial dispensers and deployed in vineyards in 2004–2007 studies to determine if mating disruption could provide a viable control option. Trials were conducted in commercial vineyards with cooperating farmers. Across all trials, mating disruption reduced pheromone trap captures of adult male mealybugs—an indication that the population numbers were lowered—and there was often a reduction mealybug numbers on vines and/or crop damage. There was not a clear reduction in the proportion of female mealybugs with ovisacs (a cottony-like mass containing mealybug eggs), but this may have resulted from the production of non-viable ovisacs that were not differentiated in the field samples. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high mealybug densities. Trap capture patterns commonly began low in April-May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. Results over all years suggest season-long coverage or late season coverage may be as or more important than dose per hectare. This research was used to help initiate the commercialization of mating disruption products for the vine mealybug, which are now being successfully used throughout the world’s grape-growing regions where this pest is found.The vine mealybug (VMB), Planococcus ficus (Hemiptera: Pseudococcidae), is a key insect pest of vineyards, and improvements in sustainable control of this pest are needed to meet increasing consumer demand for organically farmed products. One promising option is mating disruption. In a series of experiments conducted from 2004 to 2007, we tested the effects of mating disruption on trap captures of Pl. ficus males in pheromone-baited traps, on Pl. ficus numbers and age structure on vines, and on damage to grape clusters. From 2004 to 2005, the effects of dispenser load (mg active ingredient per dispenser) were also assessed, and dispensers were compared to a flowable formulation. Across all trials, mating disruption consistently reduced pheromone trap captures and often reduced mealybug numbers on vines and/or crop damage, regardless of the pheromone dose that was applied. Reductions in Pl. ficus densities in mating disruption plots were not accompanied by clear effects on mealybug population age structure; however, production of non-viable ovisacs by unmated females may have obscured differences in proportional representation of ovisacs. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high Pl. ficus densities. Trap-capture patterns in both treated and control plots commonly began low in April–May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. During the four-year trial, the release rate from plastic sachet dispensers was improved by industry cooperators as pheromone was released too quickly (2004) or not completely released during the season (2005–2006). The flowable formulation performed slightly better than dispensers at the same application dose. Results over all years suggest season-long coverage or late-season coverage may be as or more important than dose per hectare. Development of a dispenser with optimized season-long pheromone emission or targeted seasonal periods should be a future goal.

Evaluating imidacloprid exposure among grape field male workers using biological and environmental assessment tools: An exploratory study.

Imidacloprid is a neonicotinoid insecticide commonly injected through agricultural drip irrigation systems to reduce the population of vine mealybugs (P. ficus) in grape farms. There is a growing concern of potential human health effects of imidacloprid, however, there is limited information on the exposure to imidacloprid in farm workers. Imidacloprid exposure was evaluated in this exploratory study of 20 male migrant grape workers sampled five days after imidacloprid was injected in the irrigation system during winter and summer seasons. We administered a questionnaire on work activities, exposure characteristics, and socio-demographics and collected personal air, hand wipe, and spot urine samples. Heat exposure was also assessed. Spearman's correlation coefficients and Wilcoxon rank-sum tests were utilized to evaluate associations and differences in imidacloprid exposures with socio-demographic, occupational, and environmental characteristics. All participants had less than a high school education and about half identified an Indigenous language as their primary language. Although not detected in air samples, imidacloprid was detected in 85% of the hand wipes (median: 0.26: 0.41 μg/wipe, range: 0.05-7.10 μg/wipe). The majority of participants (75%) had detectable urinary concentrations of imidacloprid (median: 0.11μg/g creatinine, range: 0.05-3.90μg/g of creatinine), and nearly all (95%) had detectable urinary concentrations of 5-hydroxy-Imidacloprid (5-OH-IMI), a metabolite of imidacloprid (median: 1.28μg/g creatinine, range: 0.20-27.89μg/g creatinine). There was a significant correlation (p<0.001) between imidacloprid in hand wipes and urinary imidacloprid and 5-OH-IMI (rs: 0.67 for imidacloprid and 0.80 for 5-OH-IMI). Hand temperature was significantly and positively correlated (p<0.05) with imidacloprid concentration on hand wipes (rs: 0.70), and urinary biomarkers (rs: 0.68 for imidacloprid, and 0.60 for 5-OH-IMI) suggesting that working in high temperatures may influence the exposure and absorption of imidacloprid. Thus, research on farm workers would benefit in the future by evaluating imidacloprid exposure in relation to heat stress and other occupational factors.

MONITORING AND MANAGEMENT OF THE COTTON MEALYBUG, Phenacoccus solenopsis TINSLEY INSECT AND ITS ASSOCIATED NATURAL ENEMIES ON GREEN BEAN PLANTS

Field studies were conducted on cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Sternorrhyncha: Coccoidea: Pseudococcidae) which infested green bean plants at Atfih distract, Giza Governorate, Egypt during two successive summer and nili seasons of 2016 and 2017. The population density, activity periods and the effects of some weather factors on P. solenopsis and its associated natural enemies were considered. The obtained results revealed that in summer season the total numbers of alive stages had one peak of activity in the 3rd of July during the first and second seasons (2016 and 2017), successively. While, in nili season the total number of alive stages had one peak of activity in the 3rd and the 17th December, during the first and second seasons (2016 and 2017), respectively. The total effects of some weather factors such as maximum and minimum air temperature (°C) and relative humidity percentage (RH%) showed significantly positive relationship with the cotton mealybug population. During this study, three hymenopterous solitary endparasitoids and four predacious species were recorded. The parasitoids were Aenasius arizonensis (Girault), Anagyrus pseudococci (Girault) and Acerophagus gutierreziae Timberlake (Encyrtidae). The predacious ones were Scymnus syriacus Mars., Coccinella undecimpunctata (L.) (Coleoptera: Coccinellidae), Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) and Orius laevigatus (Fiber.) (Hemiptera: Anthocoridae). In an attempt to control this insect pest specie, eight insecticides namely, mineral oil, lufenuron, chlorpyrifos, malathion, deltamethrin, buprofezin, thiamethoxam and imidacloprid were tested on P. solenopsis and its natural enemies on green bean under field conditions. The obtained resultsindicated that imidacloprid was the highest efficacy against P. solenopsis recording 90.71–89.17% reduction of the insect population after 21 days of application. Also imidacloprid was the highest efficacy against parasitoids and predators of the cotton mealybug. IGRs toxicants (buprofezin and lufenuron) found to be safer to the predacious insects than other tested insecticides.

PENGARUH PENYARUNGAN DENGAN BERBAGAI KETEBALAN PLASTIK DAN DIAMETER BUAH TERHADAP SERANGAN PENGGEREK BUAH KAKAO Conopomorha cramerella (Snellen) (LEPIDOPTERA : GRACILLARIDAE)

This research is aimed to find out the preference of cocoa pod borer to diameter, biophysical, and biochemistry cocoa pod; the percentage of infested pods, percentage of seed damaged, and percentage of yield lost. In addition, this research is also aimed to assess the effect of plastic thickness on cacao pod rot disease, the effect of sheathing on the black ant and mealybug populations on pods. This research was conducted at Selemadeg District, Tabanan Regency from October 2009 until January 2010. The field trial was arranged into randomized complete block design (RCBD) by 15 treatments were sheathing with various thickness of plastics (S0-S4) and cocoa pod diameters (B1-B3). The results indicated that, based on the percentage of the infested pod, cocoa pod borer has preferred the fruit with diameter &gt; 4.5-7.5 cm. This condition may be contrasted, the smallest pod size (3,5-4,5 cm) was the healthiest pod, even though it contains more nutritionally compound. The smaller pod rot disease in red and green types. Sheathing by plastic of &gt; 0.02 mm thick in medium size of pods was the most effective to prevent cocoa pod borer infestation. Sheathing with plastic was not affecting the population of both black ants and mealy bugs. Based on these results, it can be suggested that sheathing with plastic of &gt; 0.02 mm thick on medium size of the pod is promising control measure to prevent yield lost caused by cocoa pod borer and cocoa pot rot disease.

POPULASI DAN TINGKAT SERANGAN HAMA KUTU PUTIH PADA UBI KAYU (Manihot esculenta Crantz) PADA BEBERAPA LOKASI PENANAMAN DI LAMPUNG

The research aimed at studying the level of attack and population of mealybug cassava in multiple cassava planting locations in Lampung Province takes place from September 2017 to January 2018. Sampling was carried out in several cassava planting locations in five villages in five sub-districts in South Lampung, Central Lampung, and East Lampung. Attack crop samples were ten plants that were systematically chosen, each at five sample points located on four diagonal lines and one at the midpoint of each field. One plant at each sample point was selected for observation of the mealybug population. The laboratory process is carried out at the Plant Pests Laboratory, Plant Protection Department, Faculty of Agriculture, University of Lampung. The results showed that mealybug were found in all locations of observation with a low population density of 0.68-3.26 individuals. per 3 leaves. Location of cassava planting does not affect the population of mealybug but this location affects crop damage which ranges from 47 - 59%. Damage to plants in South Lampung is lower than damage to plants in East Lampung and Tanjung Bintang.

Bionomics of the African Apefly (Spalgis lemolea) as A Potential Natural Enemy of the Papaya Mealybug (Paracoccus marginatus) in Tanzania

The African apefly (Spalgis lemolea Druce) is a potential natural enemy of the papaya mealybug (Paracoccus marginatus Williams and Granara de Willink). We studied the life history of apeflies in the laboratory at a temperature of 25–27 °C and a relative humidity of 55%–65% under a 12 h photoperiod condition. The papaya mealybugs and apefly larvae were collected from papaya plants in Tengeru, Arusha, Tanzania. The papaya mealybugs were introduced and allowed to multiply on potted sprouting potato plants in screened cages. In order to study the life cycle and predation of apeflies, an apefly egg was placed on an open screen-covered petri dish containing a moist blotter paper and observed for larva emergence. After the apefly larva emergence, a mixture of mealybug eggs (up to 1500), nymphs (200–250) and adults (100–150) was introduced in the petri dish each day and the consumption rate by the apefly larvae was quantified until the larvae reached pupal stage. Then, the apefly adults were collected and put into cages 30 cm × 30 cm × 30 cm containing cotton wool soaked in water, for observation of pre-mating, mating, egg-laying and life span. Results indicate that the apefly completed its life cycle in 23 days. The mean development period of the eggs was four days and the development period for the larva, pre-pupa, and pupa was nine, one and ten days respectively. The adult apefly emerged after 9 days of the pupa stage with mean body lengths of 10.1 ± 0.4 mm and 11.0 ± 0.8 mm for the males and females, respectively. The female laid an average of 68 eggs in groups of two to seven at different sites after 4–5 days of emergence. In this study one apefly larva was capable of consuming about 1983 ± 117, 123 ± 6 and 80 ± 9 papaya mealybug eggs, nymphs and adults respectively during larval stage. These results reveal the predatory potential of the apefly in suppressing the population of papaya mealybugs under field conditions.

Sustainable management approach for sucking pests control in betel leaf of Bangladesh

BackgroundBetel leaf is the oldest and now highly paid farmer’s crop, but the most vulnerable to insect pests, leading to massive yield drops in Bangladesh. For this reason, the experiment was carried out at the Spices Research Centre, Bangladesh, during the period of January 2018 to December 2018 and to assess the effectiveness of the different bio-rational approach against the betel leaf sucking pests. In this study, BARI Paan-3 was used as a test crop. Studies were important that sucking insect pests to include red mite population (black fly, white fly, red mite and mealy bug) has been found actively around the year in Bangladesh.ResultsStudies have shown that sucking insect population (black fly, white fly, red mite and mealy bug) has been found actively year round, whereas the maximum (22.7, 17.2, 16.1, and 14 adult/vine) and minimum (3.2, 2.8, 2.6, and 1.5 adult/vine) were recorded during the month of October and January, respectively. The results explored that the significant variations and the R2 value suggested that biotic factor contributes 57.9, 50.9, 51.3, and 53.7% variations in black fly, white fly, red spider mite, and mealy bug population. Among approaches, the highest mortality rate (80.56, 84.73, 82.44, and 90.96%) of black fly, white fly, red mite, and mealy bug over untreated control with maximum vine yield (18.61 t/ha) is recorded from sanitation + three alternate spraying of fizimite and antario.ConclusionsIt had concluded that sanitation of betel leaf garden along with three alternate spraying of fizimite (sodium lauryl ether) at 1 ml/l and antario WP (Bt + abamectin 0.1%) at 0.5 g/l recommended for an effective management of the betel vine sucking pest complex.