Papaya Mealybug Paracoccus Marginatus Research Articles

Rapid and equipment-free identification of papaya mealybug Paracoccus marginatus based on RPA-CRISPR/Cas12a.

Paracoccus marginatus has invaded many countries, spreading rapidly and causing significant economic losses to crops. Accurate detection during the monitoring process is critical to prevent its expansion into new areas, therefore it is necessary to develop efficient and reliable detection methods. Traditional detection methods are time-consuming and instrument-dependent owing to the morphological similarities and small sizes of P. marginatus and other mealybugs, therefore establishing an efficient, rapid, and sensitive method for field detection in resource-limited settings is critical. A sensitive and rapid detection system was developed to detect P. marginatus using recombinase polymerase amplification (RPA) combined with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a. The RPA-CRISPR/Cas12a assay distinguished P. marginatus from 10 other mealybugs. The entire process can be completed in approximately an hour, and the identification results can be determined by the naked eye using lateral flow strips or a portable mini-UV torch. A method was developed to extract DNA from P. marginatus within 5 min. This method was combined with the RPA-CRISPR/Cas12a assay to achieve rapid and simple detection. In addition, two portable thermos cups with temperature displays were used to maintain the reagents and assay reactions in the field. This assay represents the first application of portable and easily available items (mini-UV torch and thermos cup) based on the combination of RPA and CRISPR/Cas12a for rapid pest detection. This method is rapid, highly specific, and instrument-flexible, allowing for the early monitoring of P. marginatus in the field. This study provides guidance for the development of suitable management strategies. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Susceptibility baselines for the invasive mealybugs Phenacoccus manihoti and Paracoccus marginatus (Hemiptera: Pseudococcidae) in cassava ecosystem against selected neonicotinoid insecticides

In recent years, an invasive cassava mealybug Phenacoccus manihoti has been threatening cassava cultivation alongside another invasive papaya mealybug Paracoccus marginatus which invaded the country more than a decade ago. In order to evaluate their responses against the commonly used neonicotinoid insecticides: thiamethoxam 25 WG and imidacloprid 17.8 SL, acute toxicity experiments to determine the susceptibility baselines in populations of two invasive mealybugs in the cassava agro-ecosystem, namely, cassava mealybug P. manihoti and papaya mealybug P. marginatus were performed upto 15 generations. A systemic uptake method was used for the bioassay. The LC50 values of thiamethoxam for F1 generation were 3.298 ppm whereas it was 1.066 ppm for F15 in cassava mealybug. The LC50 values of F1 generation were 2.014 ppm and that of F15 generation was 1.384 ppm when tested with imidacloprid. In the case of papaya mealybug, the LC50 values ranged from 6.138 ppm (F1) to 2.503 ppm (F15) for thiamethoxam and 7.457 ppm (F1) to 3.231 ppm (F15) for imidacloprid. All the susceptibility indices calculated were less than threefold. The rate of resistance development was negative in all cases showing that none of the tested populations harboured any resistance without insecticidal selection pressure. Tentative discriminating doses were fixed for both chemicals with the help of LC95 values obtained from the bioassay experiments, namely five ppm for both thiamethoxam and imidacloprid in the case of cassava mealybug and 10 ppm and 15 ppm, respectively, for thiamethoxam and imidacloprid in the case of papaya mealybug.

Parasitoid Wasp Acerophagus papayae: A Promising Solution for the Control of Papaya Mealybug Paracoccus marginatus in Cassava Fields in Vietnam.

Cassava is a valuable export commodity crop that is often attacked by pests, causing economic losses for this crop. The papaya mealybug Paracoccus marginatus has become a major pest of cassava in Vietnam. The parasitoid wasp Acerophagus papayae has been demonstrated to be the most efficient parasitoid wasp for controlling P. marginatus in many regions. We observed the occurrence of A. papayae in Vietnam, studied the biological characteristics of A. papayae, and investigated its parasitic activity on P. marginatus. The results showed that A. papayae occurred more frequently than Anagyrus loecki, another known parasitoid of P. marginatus. The lifespan of A. papayae was approximately 16 days. In the absence of hosts, a 50% honey solution was an essential diet to increase the longevity of both female and male of A. papayae. The second instar of P. marginatus was a suitable host stage for parasitism by A. papayae. Female A. papayae laid approximately 60.8 eggs within 17 days, mostly during the first 6 to 7 days. These findings suggest that A. papayae has the potential to control P. marginatus, and could inform the development of more effective pest management strategies for cassava crops in Vietnam and other regions affected by this pest.

Resistant cassava cultivars inhibit the papaya mealybug Paracoccus marginatus population based on their interaction: from physiological and biochemical perspectives

Paracoccus marginatus papaya mealybugs cause considerable threats and challenges to cassava production and processing. The deployment of resistant cultivars offers effective, economical and eco-friendly management strategies for pest management. We measured P. marginatus mortality, development and reproduction to evaluate the resistance of fifteen cassava cultivars and conducted physiological and biochemical analyses when P. marginatus was fed on two resistant cultivars (Myanmar and C1115) and three susceptible cultivars (BRA900, Bread, SC205). Significantly lower digestive (amylase, sucrase, lipase), detoxification (glutathione-S-transferase and carboxylesterase) and antioxidant activity, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO), enzyme activities were observed in P. marginatus feeding on resistant cultivars compared to susceptible cultivars. For resistant cultivars, a significant reduction was found in nutritional components containing free amino acids, nitrogen, soluble sugars and the secondary metabolite malondialdehyde. Additionally, significantly higher enzymatic activity (SOD, CAT, POD and PPO) levels and secondary metabolite quantities (total phenol and tannins) were found in resistant cultivars induced by P. marginatus compared with susceptible ones. Additionally, RT-qPCR tests showed that the transcripts of ten genes involved in nutrition, secondary metabolites and antioxidant activities were consistent with physiology changes. Thus, the resistant cultivars suffered lower P. marginatus damage by elevating secondary metabolite contents and antioxidant activities, reducing plant nutrition levels and decreasing insect enzymatic activities. This study will be beneficial in developing indices for standard regulation to evaluate P. marginatus-resistant cassavas and effectively manage this pest.

Arthropod Pests and Their Natural Enemies Associated with Cotton in India: A Review

Globally cotton is the most important natural fibre crop being cultivated commercially for domestic textile needs and export. Cotton plays an important role in India’s economy, occupies largest acreage and highest production in the world. In India, cotton is being grown in 10 major states divided in 3 distinct zones viz., north, central and south with varying climate and soil. Despite large acreage, cotton productivity in India is far below world average due to variety of reasons. Among them damage caused due to arthropod pests is vital. In this article authors have attempted through extensive literature survey, to provide up to date information on arthropod pests and their natural enemies associated with cotton crop in India. It is observed that, in India, cotton crop is attacked by 251 arthropod pest species (including insect and mites) belonging to 9 insect orders and 1 order from Acarina. Among these, about 12 species of insects are major pests causing significant losses to cotton crop while remaining species are either occasional, sporadic or minor in nature. Overall these pests cause economic damage to cotton crop in a range between 20-60 per cent. The major arthropod pests are sucking insects namely leafhopper Amrasca biguttula biguttula (Ishida), aphid Aphis gossypii Glover, thrips Thrips tabaci Lindeman., whitefly Bemisia tabaci (Gennadius), Cotton mealybug Phenacoccus solenopsis Tinsley, Papaya mealybug Paracoccus marginatus Williams and Granara de Willink, and Indian cotton mirid bug Creontiades biseratense (Distant). The bollworm complex is another major group of insects that attack cotton and comprises of American bollworm Helicoverpa armigera (Hubner), spotted bollworms Earias insulana (Boisduval), E. vitella (F.) and pink bollworm Pectinophora gossypiella (Saunders). Other pests like stem weevil Pempherulus affinis Faust and tobacco caterpillar Spodoptera litura F., are also categorized as major pests. A rich fauna of 368 natural enemies (including 174 species of predators and 194 species of parasitoids/parasites) play significant role as biological control agents to check arthropod pests in cotton ecosystems of India. In this review there is addition of 85 arthropod pests over previously reported 166 arthropod pests. This updated information on cotton pests and their important natural enemies may serve as an important guide to researchers and policy makers in carrying out potential pest risk assessment and devising appropriate management strategies for economically damaging cotton pests.

Evaluation of Some Reproductive and Developmental Parameters of Paracoccus Marginatus (Hemiptera: Pseudococcidae) Under Laboratory Conditions

The papaya mealybug Paracoccus marginatus Williams and Granara De Willink (Hemiptera: Pseudococcidae) is an invasive insect species attacking a diverse range of host plants. It causes an enormous damage to crops including those of very great economic importance including the papaya, being its main host. Considering its potential threat to fruit and crops of economic importance throughout Togo, this study, which was carried out in the laboratory under conditions of 28 ± 2°C, 75 ± 5% RH, 12 : 12 LD, made it possible to determine some biological parameters of P. marginatus, essential for the implementation of management programmes for this species. The results showed that a female of P. marginatus had three periods of reproductive activity, namely pre-oviposition, oviposition and post-oviposition periods which last on average 7.74 ± 1.26; 6.13 ± 3.02 and 7.45 ± 4.27 days respectively. During oviposition, a female P. marginatus lays an average of 25.262 ± 11.16 eggs per day, for an average total of 224.32 ± 29.99 eggs during her lifetime, which averages 18.44 ± 3.31 days. During the post-embryonic development of P. marginatus which lasts on average 25.98 ± 4.47 days for the female against 29.70 ± 5.58 days for the male and which passes through three larval stages, the important mortality rates of the first and second larval stages were noted. They are estimated to an average of 61.40 ± 0.05 and 52.8 ± 0.025 respectively. However, at the third stage, the rate is 35.02 ± 0.03 for the female and zero for the male. These results provide a better understanding of the biology of P. marginatus under local conditions and thus provide a basis for controlling the population of the species and the damage it causes in Togo.

Characterization and risk assessment of the invasive papaya mealybug, Paracoccus marginatus, in Kenya under changing climate

AbstractThe present study was conducted to characterize the newly invasive papaya mealybug Paracoccus marginatus Williams and Granara de Willink in Kenya using molecular techniques and to establish the potential risk of spread of the pest. Although abundant literature of P. marginatus outbreaks exists in other parts of the world, studies from Africa are rare. Our results revealed significant similarity between Kenyan samples with GenBank accession number KP692333.1 of P. marginatus. Phylogenetic analyses generated a tree that was paraphyletic with two clusters showing low genetic distance values for the P. marginatus sequences, which diverged from that of Planococcus citri. Our models displayed an optimal performance with mean area under the curve value of 0.82 and 0.98 for Genetic Algorithm for Rule‐Set Production (GARP) and maximum entropy modelling (MaxEnt), respectively. Isothermality was the most influential variable in determining the potential distribution of P. marginatus with a 69% contribution to the models. Other variables included temperature mean diurnal range temperature seasonality, temperature annual range and annual precipitation in decreasing order of contribution. Current prediction by both models exceeded the existing range of P. marginatus, exacerbating the potential threat of the pest. GARP was more conservative in predicting suitable areas for P. marginatus, while MaxEnt showed further expansion by the year 2050. Our findings provide important information to guide biosecurity agencies in decision‐making to prevent the spread and enhance control efforts of P. marginatus.

Insecticidal property of Citrus sinensis fruit waste against papaya mealybug Paracoccus marginatus

Laboratory experiments were conducted during August to March, 2018–2019, to evaluate the insecticidal property of Citrus sinensis (L.) Osbeck fruit waste viz., peel and seed against the papaya mealybug Paracoccus marginatus (Williams and Granara de Willink). Five solvents, viz., hexane, ethyl acetate, methanol, diethyl ether and dichloromethane were used to extract the bioactive compounds. The efficacy of these extracts was evaluated against P. marginatus at 10000 ppm for their oral or contact toxicity, through leaf contamination and dry film method, respectively. The methanol extract was observed to exert maximum mortality of P. marginatus in leaf contamination method (88.89% and 86.11%, respectively) and also dry film method (88.33%, 78.06%, respectively) after 72 hr after treatment. The chemical profile of the methanol extract of seed and peel analysed with GC-MS was also done.

Specificity in host instar selection, parasitism and developmental time of Acerophagus papayae (Hymenoptera: Encyrtidae) on Paracoccus marginatus

Acerophagus papayae an introduced solitary koinobiont endoparasitoid, is the efficient parasitoid for the suppression of papaya mealybug Paracoccus marginatus. Host instars preference, parasitic potential, emergence rate and developmental time of A. papayae on P. marginatus of five different host plants like papaya (Carica papaya), mulberry (Morus alba), brinjal (Solanum melongena), cassava (Manihot esculenta) and congress grass (Parthenium hysterophorus) were studied. The study revealed that A. papayae preferred to parasitize all stages of P.marginatus. The highest parasitism was recorded in second and third instar and lowest in adult and first instars of P. marginatus. Mealybugs from papaya and mulberry are highly susceptible to parasitisation than parthenium, tapioca and brinjal. Further high adult parasitoid emergence was recorded from mealybugs on papaya.

Chemical Profiling and Insecticidal Activity of <em>Artemisia herba-alba</em> Essential Oil Against Papaya Mealybug <em>Paracoccus marginatus</em> ‎(Hemiptera: Pseudococcidae)

The current study aimed to investigate the chemical composition and insecticidal activity of Artemisia herba-alba essential oil obtained by hydrodistillation and solvent extraction against papaya mealybug Paracoccus marginatus. The essential oil was analysed using gas chromatography-mass spectrometry and the insecticidal activity was recorded for different times and concentrations under laboratory conditions. According to GC-MS results, the chemical components detected of essential oil isolated by ‎hydrodistillation and solvent extraction were 52 and 62 compounds of both extraction methods, the main components of essential oil of hydrodistillation method were eucalyptol (32.81%), &alpha-pinene (28.62%) and linalol (10.18%) while the major components of essential oil isolated by solvent extract were pentadecanoic acid (16.69%) and dihomo-‎‎.gamma.-linolenic acid (15.2%). The essential oil of hydrodistillation method exhibited more insecticidal ‎activity than solvent extract method against P. marginatus, 1000 mg/L of essential oil isolated by ‎hydrodistillation achieved 100% ‎mortality of papaya mealybugs after 120, ‎‎168 h of treatment with LC50 values which ‎was‎‎ 65.362 mg/L after 168 h from treatment and LT50 value which was ‎22.386 h‎‏‎‎ at 1000 mg/L.‎ The findings reveal and propose that the essential oil of A. herba-albais a rich by bioactive components and it is a prospective source of botanical insecticides.

Effect of temperature on the biology and fitness traits of papaya mealybug parasitoid Acerophagus papayae

Effect of temperature on the parasitoid Acerophagus papayae of papaya mealy bug Paracoccus marginatus was studied. The results revealed that its parasitism drastically decreased with increase in temperature. Though parasitism was noticed at all temperatures, there was a strong negative correlation and % parasitism increased from 20 to 32°C. The peak in parasitism was at 32°C (52.7, 38.26 and 4.8%) with second, third nymphal and adult female stages, respectively. Thereafter the parasitism rate decreased with rise in temperature. The maximum parasitism was observed with the second instar nymph compared to the third instar and adult stages. Adult emergence increased with temperature till 32°C, thereafter a drastic drop was evident; emergence was maximum at 32°C with all host stages (76.8, 74.35 and 71.28% of 2nd, 3rdnymphal stages and adult female, respectively). The least emergence of adult parasitoid was at 20°C (60.9, 58.9 and 52.7% in respective host stages). The maximum developmental time (10.6 days) for A. papayae was found at 20°C; at 25 and 30°C it was observed to be same (7.15 and 7.0 days, respectively). The least developmental time of 5.0 days was observed at 35°C. More number of Male of A. papayae emerged from second instar of female P. marginatus at 30°C. The highest female to male sex ratio was noticed at 30°C (1: 1.74), followed by 25°C (1: 1.50).

Chemical ecology of Acerophagus papayae Noyes and Schauff Vis-à-Vis Gas Chromatography

The chemical ecology of the parasitoid Acerophagus papayae Noyes and Schauff was studied with Gas Chromatography-Mass Spectrometry (GC-MS) volatiles analysis. The biochemical constituents and secondary metabolites in the host plant leaves revealed variation in influencing the growth and development of papaya mealybug Paracoccus marginatus Williams and Granara de Willink, which indirectly influenced the parasitoid efficiency too. Healthy and infested leaves of papaya and tapioca were analysed for the released volatile compounds (VOCs), and identified with GC-MS. It was observed that the VOCs like octanol, isocaryophyllene, hexadecane, pentadecane, heptadecane, morphinan and octasiloxane might probably attract the mealybug for sustained feeding in papaya. In tapioca, heptane, pyran, a-ocimene, octadien-3-ol, decane, butylated hydroxytoluene and dibutyl phthalate (DBP) were observed as probable reasons for repelling or prohibiting the mealybug from feeding.

Effect of Native and Non-native Hosts on the Biology of <I>Acerophagus papayae</I> Noyes and Schauff, the Introduced Parasitoid of <I>Paracoccus marginatus</I> Williams and Granara De Willink

The bioecology study of any parasitoid using alternative hosts imposes divergent selection pressures on parasitoid populations. In this study, we investigated the bioecology potential of parasitoid Acerophagus papayae Noyes and Schauff on papaya mealybug Paracoccus marginatus Williams and Granara De Willink from different plant hosts. The parameters studied were adult longevity (survival of progeny), fecundity and productivity of female mealybugs and sex ratio of progenies of P. marginatus . The results showed significant differences in bioecology of parasitoid on their natal host ( P. marginatus from papaya) compared with the non-natal hosts ( P. marginatus from non papaya hosts). It is also compared with honey concentration solution and potato sprouts. The parasitoid is well adapted to the natal host that is papaya compared to others host. However, parasitoids showed a similar high fitness on both natal and non natal hosts. This results could be used to increase the effectiveness of biological control programme on different views.

BIOLOGI DAN NERACA HAYATI KUTU PUTIH PEPAYA PARACOCCUS MARGINATUS WILLIAMS & GRANARA DE WILLINK (HEMIPTERA: PSEUDOCOCCIDAE) PADA TIGA JENIS TUMBUHAN INANG

Biology and life table of papaya mealybug Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae) on three host plant species. The papaya mealybug, Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae), has been considered as a new invasive pest causing heavy damage on papaya in Indonesia since 2008. The pest is polyphagous with more than 55 host plant species. Study was conducted in laboratory with the objectives to determine developmental biology and life table parameters of the mealybug feeding on papaya, physic nut, and cassava leaves. Host plant species affected papaya mealybug performances. Egg stage lasted 7.25, 8.09, and 9.86 d on papaya, physic nut, and cassava, respectively. The shortest female nymphal developmental time was on papaya (18.91 d) and the longest on cassava (32.45 d). Longevity of adult males ranged from 1.09-2.85 d while females 12.29-14.93 d. When the mealybugs were reared on a seedling, the fecundity was higher on papaya (324.6) than those on physic nut (186.6) and cassava (157.5). No egg production occurred in virgin females. The sex ratio of P. marginatus favoured females, which comprised about 90% of population on papaya and cassava. The intrinsic rate of increase (rm) was significantly different among hosts, with the highest rate (0.117 female offspring/female/d) on papaya, followed by physic nut (0.079) and cassava (0.057). The maximum values of rmalong with net reproductive rate (Ro) and finite rate of increase(λ), and the shortest mean generation time (T) and doubling time (Dt) on papaya, indicating that papaya was the more favorable host plant for P.marginatus.

POPULASI DAN SERANGAN KUTU PUTIH PEPAYA, PARACOCCUS MARGINATUS (HEMIPTERA: PSEUDOCOCCIDAE) PADA TANAMAN PEPAYA DI DAERAH DATARAN RENDAH SUMATERA SELATAN

Populations and damage by the papaya mealybug Paracoccus marginatus (Hemiptera: Pseudococcidae) on papaya inlowland areas of South Sumatera. One of the main problems in papaya cultivation today is the presence of a newlyintroduced pest, the white papaya mealybug, Paracoccus marginatus (Hemiptera: Pseudococcidae). This study aimed toobserve the mealybug populations and its damage percentage in papaya plants and to identify its host plants in SouthSumatera. The study was carried out on the fruit and vegetable producing area in Indralaya, South Sumatera. The survey wasconducted on papaya plantation plots with a minimum size of 1000 m2. Data from the observation indicated that populationsof P. marginatus on papaya fruit were not significantly different to those on papaya leaves, except for the first observation inthe rainy season. In general, the percentages of mealybug damages were not affected by the season and the percentages ofdamage on the leaves were not different from those on the fruits of the papaya plants. Inventory of P. marginatus host plantson the area resulted in a total of 12 species of host plants dominated by dicotyledonous plant species. The host plants werefrom 11 families, i.e. Anacardiaceae, Caricaceae, Cucurbitaceae, Euphorbiaceae, Fabaceae, Myrtaceae, Rosaceae, Rutaceae,Sapindaceae, Sapotaceae, and Solanaceae.

Economic impact of classical biological control of papaya mealybug in India

Farmers in Tamil Nadu, India began to report that a new pest was affecting papaya (Carica papaya L.) in 2006. Numerous applications of insecticide were made, but papaya losses were severe and the pest spread to several other crops. The pest was identified in 2008 as the papaya mealybug Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae), and a classical biological control program was initiated. Three parasitoids, Acerophagus papayae Noyes and Schauff, Pseudleptomastix mexicana Noyes and Schauff, and Anagyrus loecki Noyes and Menezes (Hymenoptera: Encyrtidae), were imported from Puerto Rico in July 2010, and A. papayae was multiplied and released. Excellent control of the papaya mealybug was obtained within five months, pesticide usage was reduced, and production and income were increased. The purpose of this article is to quantify the economic benefits of this classical biological control program. The annual economic benefits for the five most important crops affected by the biocontrol program range from $121 million to $309 million, and the net present value of benefits over five years total $524 million to $1.34 billion. Implications are drawn for biological control programs in other countries.

KEEFEKTIFAN TIGA JENIS INSEKTISIDA NABATI TERHADAP KUTU PUTIH PEPAYA PARACOCCUS MARGINATUS DAN KEAMANANNYA TERHADAP LARVA KUMBANG PREDATOR CURINUS COERULEUS

Effectiveness of three botanical insecticides against the papaya mealybug Paracoccus marginatus and their safety to the predatory Curinus coeruleus larvae. Preparations of Tephrosia vogelii (Tv) leaf extract (0.5% and 1% w/v), Annona squamosa (As) seed extract (0.5% and 1%), and Cinnamomum multiforum (Cm) leaf essential oil (1% and 2%), and their mixtures (Mix-1: Tv 0.25% + As 0.25% + Cm 0.5%; Mix-2: Tv 0.5% + As 0.5% + Cm 1%) were tested for their effectiveness on third-instar nymphs of Paracoccus marginatus by spraying the test materials on undetached papaya leaves and by direct spraying on the test insects using Potter spray tower. Tv extract was also applied on the test insects placed on undetached papaya leaves. The safety test was done by direct spraying of the test materials on the predatory Curinus coeruleus larvae using Potter spray tower. Tv and As extracts at a concentration of 1% each are potential to be used for the control of P. marginatus. Spraying of T. vogelii extract on the test P. marginatus nymphs placed on papaya leaves was more effective than spraying of the test materials on papaya leaves or direct spraying on the test insects only. The treatment with Cm essential oil required twice the concentration of Tv and As extracts to obtain the same level of effectiveness. The treatment with Mix-2 caused lower P. marginatus mortality than the sum of mortality caused by its components applied separately. Nonetheless, the three botanical insecticides and their mixtures were safe to C. coeruleus larvae. On the other hand, although the synthetic insecticide imidacloprid (neonicotinoid), included in the study for comparison, was effective against P. marginatus, it was also toxic to the predatory C. coeruleus larvae so its use should be avoided or limited.