Potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) is a key pest of potato (Solanum tuberosum L., Solanales: Solanaceae) and a vector of "Candidatus Liberibacter solanacearum," the pathogen associated with zebra chip disease. In addition to its presence on cultivated crops, the p...
Efectividad biológica de insecticidas contra el psílido de la papa (Bactericera cockerelli Sulc.) en Metepec Estado de México y transmisión de bacterias no cultivadas asociadas a enfermedades en papa (Solanum tuberosum L.)
López Duran, María Felipa
Con el propósito de identificar insecticidas efectivos para el manejo del psílido de la papa Bactericera cockerelli Sulc., y reducir la incidencia de la Punta Morada de la Papa (PMP), se realizó un experimento en Metepec, Edo. de México, donde se evaluaron siete insecticidas de diferentes grupos toxicológicos. Los mejores insecticidas para el control de huevos y adultos del psílido fueron extracto de nim y abamectina con 69.8 y 84.8% de efectividad biológica, mientras que para...
Lopez, Beatriz; Favela, Susana; Ponce, Gustavo; Foroughbakhch, Rahim; Flores, Adriana E
Bactericera cockerelli (Sulc) is a significant pest of several solanacious crops in Mexico and the United States since 1970. In 2001 significant outbreaks of outstanding importance were observed for the first time in areas where infestations of this insect were historically rare. Molecular studies revealed that this was because of the development of a new biotype of B. cockerelli that had become adapted to south-western United States, further demonstrating that this genetic differentiation was reflected in the survival, development cycle, fertility, and growth rate of both the native biotype as well as the one recently reported. To determine genetic variation in populations of B. cockerelli from Mexico, inter simple sequence repeat were used. Results showed that populations of B. cockerelli from central and northeastern Mexico (Guanajuato, Morelos, Estado de Mexico, and Nuevo Leon states) are genetically similar, meanwhile B. cockerelli from northwest, southwest, and southeast of the country (Sinaloa, Michoacan, and Oaxaca states) are genetically distinct from each other and from the rest of the populations included in the study.
The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), is a vector of the bacterium “Candidatus Liberibacter solanacearum,” the putative causal agent of potato zebra chip disease that has seriously affected the potato industry in the Central and Southwestern United States for the...
Lewis, O M; Michels, G J; Pierson, E A; Heinz, K M
Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) is a pest of potato (Solanum tuberosum L.) that vectors the bacterium that putatively causes zebra chip disease in potatoes, 'Candidatus Liberibacter solanacearum.' Zebra chip disease is managed by controlling populations of B. cockerelli in commercial potato fields. Lacking an integrated pest management strategy, growers have resorted to an intensive chemical control program that may be leading to insecticide-resistant B. cockerelli populations in south Texas and Mexico. To initiate the development of an integrated approach of controlling B. cockerelli, we used constant temperature studies, nonlinear and linear modeling, and field sampling data to determine and validate the degree day parameters for development of B. cockerelli infesting potato. Degree day model predictions for three different B. cockerelli life stages were tested against data collected from pesticide-free plots. The model was most accurate at predicting egg-to-egg and nymph-to-nymph peaks, with less accuracy in predicting adult-to-adult peaks. It is impractical to predict first occurrence of B. cockerelli in potato plantings as adults are present as soon cotyledons break through the soil. Therefore, we suggest integrating the degree day model into current B. cockerelli management practices using a two-phase method. Phase 1 occurs from potato planting through to the first peak in a B. cockerelli field population, which is managed using current practices. Phase 2 begins with the first B. cockerelli population peak and the degree day model is initiated to predict the subsequent population peaks, thus providing growers a tool to proactively manage this pest. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Full Text Available Potato psyllid (Bactericera cockerelli is an important pest of potato, tomato and pepper. Not only could a toxin secreted by nymphs results in serious phytotoxemia in some host plants, but also over the past few years B. cockerelli was shown to transmit "Candidatus Liberibacter solanacearum", the putative bacterial pathogen of potato zebra chip (ZC disease, to potato and tomato. ZC has caused devastating losses to potato production in the western U.S., Mexico, and elsewhere. New knowledge of the genetic diversity of the B. cockerelli is needed to develop improved strategies to manage pest populations. Mitochondrial genome (mitogenome sequencing provides important knowledge about insect evolution and diversity in and among populations. This report provides the first complete B. cockerelli mitogenome sequence as determined by next generation sequencing technology (Illumina MiSeq. The circular B. cockerelli mitogenome had a size of 15,220 bp with 13 protein-coding gene (PCGs, 2 ribosomal RNA genes (rRNAs, 22 transfer RNA genes (tRNAs, and a non-coding region of 975 bp. The overall gene order of the B. cockerelli mitogenome is identical to three other published Psylloidea mitogenomes: one species from the Triozidae, Paratrioza sinica; and two species from the Psyllidae, Cacopsylla coccinea and Pachypsylla venusta. This suggests all of these species share a common ancestral mitogenome. However, sequence analyses revealed differences between and among the insect families, in particular a unique region that can be folded into three stem-loop secondary structures present only within the B. cockerelli mitogenome. A phylogenetic tree based on the 13 PCGs matched an existing taxonomy scheme that was based on morphological characteristics. The available complete mitogenome sequence makes it accessible to all genes for future population diversity evaluation of B. cockerelli.
Luna-Cruz, Alfonso; Rodríguez-Leyva, Esteban; Lomeli-Flores, J Refugio; Ortega-Arenas, Laura D; Bautista-Martínez, Néstor; Pineda, Samuel
Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) is one of the most economically important pests of potato, tomato, and peppers in Central America, Mexico, the United States, and New Zealand. Its control is based on the use of insecticides; however, recently, the potential of the eulophid parasitoid Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) for population regulation has been studied. Because T. triozae is likely to be exposed to insecticides on crops, the objective of this study was to explore the compatibility of eight insecticides with this parasitoid. The toxicity and residual activity (persistence) of spirotetramat, spiromesifen, beta-cyfluthrin, pymetrozine, azadirachtin, imidacloprid, abamectin, and spinosad against T. triozae adults were assessed using a method based on the residual contact activity of each insecticide on tomato leaf discs collected from treated plants growing under greenhouse conditions. All eight insecticides were toxic to T. triozae. Following the classification of the International Organization of Biological Control, the most toxic were abamectin and spinosad, which could be placed in toxicity categories 3 and 4, respectively. The least toxic were azadirachtin, pymetrozine, spirotetramat, spiromesifen, imidacloprid, and beta-cyfluthrin, which could be placed in toxicity category 2. In terms of persistence, by day 5, 6, 9, 11, 13, 24, and 41 after application, spirotetramat, azadirachtin, spiromesifen, pymetrozine, imidacloprid, beta-cyfluthrin, abamectin, and spinosad could be considered harmless, that is, placed in toxicity category 1 (insecticides allow them to be considered within integrated pest management programs that include T. triozae. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Vargas-Madríz, Haidel; Bautista-Martínez, Néstor; Vera-Graziano, Jorge; Sánchez-García, Prometeo; García-Gutiérrez, Cipriano; Sánchez-Soto, Saúl; de Jesús García-Avila, Clemente
Abstract It is known that some nutrients can have both negative and positive effects on some populations of insects. To test this, the Logrank test and the Interval Overlap Test were evaluated for two crop cycles (February–May and May–August) of the 7705 tomato hybrid, and the effect on the psyllid, Bactericera cockerelli (Sulc.) (Hemiptera: Triozidae), was examined under greenhouse conditions. Tomato plants were in polythene bags and irrigated with the following solutions: T1—Steiner solution, T2—Steiner solution with nitrogen reduced to 25%, T3—Steiner solution with potassium reduced to 25%, and T4—Steiner solution with calcium reduced to 25%. In the Logrank test, a significant difference was found when comparing the survival parameters of B. cockerelli generated from the treatment cohorts: T1–T2; T1–T3; T1–T4; T2–T3; and T3–T4, while no significant differences were found in the T2–T4 comparison in the February–May cycle. In the May–August cycle, significant differences were found when comparing the survival parameters generated from the treatment cohorts: T1–T2; T1–T3; and T1–T4, while no significant differences were found in the T2–T3; T2–T4; and T3–T4 comparisons of survival parameters of B. cockerelli fed with the 7705 tomato hybrid. Also, the Interval Overlap Test was done on the treatment cohorts (T1, T2, T3, and T4) in the February–May and May–August cycles. T1 and T2 compare similarly in both cycles when feeding on the treatments up to 36 d. Similarly, in T1 and T3, the behavior of the insect is similar when feeding on the treatments up to 40 and 73 d, respectively. Comparisons T2–T3 and T2–T4 are similar when feeding on both treatments up to 42, 38 and 37, 63 d, respectively. Finally, the T3–T4 comparison was similar when feeding in both treatments up to 20 and 46 d, respectively. RESUMEN. Se sabe que algunos nutrientes pueden tener efectos tanto negativos como positivos en algunas poblaciones de
Full Text Available The potato/tomato psyllid, Bactericera cockerelli (B. cockerelli, is an important plant pest and the vector of the phloem-limited bacterium Candidatus Liberibacter psyllaurous (solanacearum, which is associated with the zebra chip disease of potatoes. Previously, we reported induction of RNA interference effects in B. cockerelli via in vitro-prepared dsRNA/siRNAs after intrathoracic injection, and after feeding of artificial diets containing these effector RNAs. In order to deliver RNAi effectors via plant hosts and to rapidly identify effective target sequences in plant-feeding B. cockerelli, here we developed a plant virus vector-based in planta system for evaluating candidate sequences. We show that recombinant Tobacco mosaic virus (TMV containing B. cockerelli sequences can efficiently infect and generate small interfering RNAs in tomato (Solanum lycopersicum, tomatillo (Physalis philadelphica and tobacco (Nicotiana tabacum plants, and more importantly delivery of interfering sequences via TMV induces RNAi effects, as measured by actin and V-ATPase mRNA reductions, in B. cockerelli feeding on these plants. RNAi effects were primarily detected in the B. cockerelli guts. In contrast to our results with TMV, recombinant Potato virus X (PVX and Tobacco rattle virus (TRV did not give robust infections in all plants and did not induce detectable RNAi effects in B. cockerelli. The greatest RNA interference effects were observed when B. cockerelli nymphs were allowed to feed on leaf discs collected from inoculated or lower expanded leaves from corresponding TMV-infected plants. Tomatillo plants infected with recombinant TMV containing B. cockerelli actin or V-ATPase sequences also showed phenotypic effects resulting in decreased B. cockerelli progeny production as compared to plants infected by recombinant TMV containing GFP. These results showed that RNAi effects can be achieved in plants against the phloem feeder, B. cockerelli, and the TMV
Cooper, W Rodney; Horton, David R; Unruh, Thomas R; Garczynski, Stephen F
Potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae), is a key pest of potato (Solanum tuberosum L., Solanales: Solanaceae) and a vector of "Candidatus Liberibacter solanacearum," the pathogen associated with zebra chip disease. In addition to its presence on cultivated crops, the psyllid regularly occurs on numerous uncultivated annual and perennial species within the Solanaceae. A better understanding of landscape-level ecology of B. cockerelli would substantially improve our ability to predict which potato fields are most likely to be colonized by infected psyllids. We developed three PCR-based methods of gut content analysis to identify what plant species B. cockerelli had previously fed upon. These methods included-1) sequencing PCR amplicons of regions of plant-derived internal transcribed spacer (ITS) or the chloroplast trnL gene from psyllids, 2) high-resolution melting analysis of ITS or trnL real-time PCR products, and 3) restriction enzyme digestion of trnL PCR product. Each method was used to test whether we could identify psyllids that had been reared continuously on potato versus psyllids reared continuously on the perennial nightshade, Solanum dulcamara. All three methods of gut content analysis correctly identified psyllids from potato and psyllids from S. dulcamara Our study is the first to demonstrate that plant DNA can be detected in a phloem-feeding insect. Gut content analysis, in combination with other landscape ecology approaches, could help elucidate patterns in landscape-level movements and host plant associations of B. cockerelli. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the United States.
Venkatesan G Sengoda
Full Text Available "Candidatus Liberibacter solanacearum" (Lso is an economically important pathogen of solanaceous crops and the putative causal agent of zebra chip disease of potato (Solanum tuberosum L.. This pathogen is transmitted to solanaceous species by the potato psyllid, Bactericera cockerelli (Šulc, but many aspects of the acquisition and transmission processes have yet to be elucidated. The present study was conducted to assess the interacting effects of acquisition access period, incubation period, and host plant on Lso titer in psyllids, the movement of Lso from the alimentary canal to the salivary glands of the insect, and the ability of psyllids to transmit Lso to non-infected host plants. Following initial pathogen acquisition, the probability of Lso presence in the alimentary canal remained constant from 0 to 3 weeks, but the probability of Lso being present in the salivary glands increased with increasing incubation period. Lso copy numbers in psyllids peaked two weeks after the initial pathogen acquisition and psyllids were capable of transmitting Lso to non-infected host plants only after a two-week incubation period. Psyllid infectivity was associated with colonization of insect salivary glands by Lso and with Lso copy numbers >10,000 per psyllid. Results of our study indicate that Lso requires a two-week latent period in potato psyllids and suggest that acquisition and transmission of Lso by psyllids follows a pattern consistent with a propagative, circulative, and persistent mode of transmission.
Potato psyllid, Bactericera cockerelli (Šulc), is a vector of the bacterium that causes zebra chip disease of potato (Solanum tuberosum L.). When cultivated crops are not available, potato psyllid may often be found on non-crop hosts within the Solanaceae. This study determined that species of Lyci...
Glenda L Torres
Full Text Available "Candidatus Liberibacter solanacearum" (Proteobacteria is an important pathogen of solanaceous crops (Solanales: Solanaceae in North America and New Zealand, and is the putative causal agent of zebra chip disease of potato. This phloem-limited pathogen is transmitted to potato and other solanaceous plants by the potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae. While some plants in the Convolvulaceae (Solanales are also known hosts for B. cockerelli, previous efforts to detect Liberibacter in Convolvulaceae have been unsuccessful. Moreover, studies to determine whether Liberibacter can be acquired from these plants by B. cockerelli are lacking. The goal of this study was to determine whether horizontal transmission of Liberibacter occurs among potato psyllids on two species of Convolvulaceae, sweet potato (Ipomoea batatas and field bindweed (Convolvulus arvensis, which grows abundantly in potato growing regions of the United States. Results indicated that uninfected psyllids acquired Liberibacter from both I. batatas and C. arvensis if infected psyllids were present on plants concurrently with the uninfected psyllids. Uninfected psyllids did not acquire Liberibacter from plants if the infected psyllids were removed from the plants before the uninfected psyllids were allowed access. In contrast with previous reports, PCR did detect the presence of Liberibacter DNA in some plants. However, visible amplicons were faint and did not correspond with acquisition of the pathogen by uninfected psyllids. None of the plants exhibited disease symptoms. Results indicate that horizontal transmission of Liberibacter among potato psyllids can occur on Convolvulaceae, and that the association between Liberibacter and Convolvulaceae merits additional attention.
Torres, Glenda L; Cooper, W Rodney; Horton, David R; Swisher, Kylie D; Garczynski, Stephen F; Munyaneza, Joseph E; Barcenas, Nina M
"Candidatus Liberibacter solanacearum" (Proteobacteria) is an important pathogen of solanaceous crops (Solanales: Solanaceae) in North America and New Zealand, and is the putative causal agent of zebra chip disease of potato. This phloem-limited pathogen is transmitted to potato and other solanaceous plants by the potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae). While some plants in the Convolvulaceae (Solanales) are also known hosts for B. cockerelli, previous efforts to detect Liberibacter in Convolvulaceae have been unsuccessful. Moreover, studies to determine whether Liberibacter can be acquired from these plants by B. cockerelli are lacking. The goal of this study was to determine whether horizontal transmission of Liberibacter occurs among potato psyllids on two species of Convolvulaceae, sweet potato (Ipomoea batatas) and field bindweed (Convolvulus arvensis), which grows abundantly in potato growing regions of the United States. Results indicated that uninfected psyllids acquired Liberibacter from both I. batatas and C. arvensis if infected psyllids were present on plants concurrently with the uninfected psyllids. Uninfected psyllids did not acquire Liberibacter from plants if the infected psyllids were removed from the plants before the uninfected psyllids were allowed access. In contrast with previous reports, PCR did detect the presence of Liberibacter DNA in some plants. However, visible amplicons were faint and did not correspond with acquisition of the pathogen by uninfected psyllids. None of the plants exhibited disease symptoms. Results indicate that horizontal transmission of Liberibacter among potato psyllids can occur on Convolvulaceae, and that the association between Liberibacter and Convolvulaceae merits additional attention.
Lévy, Julien; Hancock, Joseph; Ravindran, Aravind; Gross, Dennis; Tamborindeguy, Cecilia; Pierson, Elizabeth
This study provides a protocol for rapid DNA isolation from psyllid vectors (Bactericera cockerelli and Diaphorina citri) that can be used directly with DNA-based methods for the detection of 'Candidatus (Ca.) Liberibacter solanacearum,' the bacterial causal agent of potato zebra chip disease and eventually for 'Ca. Liberibacter asiaticus' the causal agent of huanglongbing disease in citrus. The fast DNA extraction protocol was designed to work with conventional polymerase chain reaction (cPCR) DNA amplification as well as Loop mediated PCR DNA amplification. Direct cPCR of the psyllid 28S rDNA gene from samples prepared using the fast DNA extraction method was as reliable as from samples prepared using standard DNA purification (> 97% from live insects) as tested in B. cockerelli. However, samples prepared using the fast DNA extraction method had to be diluted 1:100 in sterile water for reliable amplification, presumably to dilute PCR inhibitors in the crude extract. Similarly, both cPCR and loop mediated PCR DNA amplification detected 'Ca. Liberibacter' in psyllids infected with either the zebra chip or huanglongbing pathogen equally well from diluted samples prepared using the fast DNA extraction method or from samples prepared using a DNA purification step. In addition to being reliable, the time required to complete the fast DNA extraction for 10 samples was on average approximately 5 min and required no special reagents or laboratory equipment. Thus, the fast DNA extraction method shows strong promise as a rapid, reliable, and expedient method when coupled with PCR-based analyses for detection of 'Ca. Liberibacter' pathogens in psyllids.
Use of Electrical Penetration Graph Technology to Examine Transmission of 'Candidatus Liberibacter solanacearum' to Potato by Three Haplotypes of Potato Psyllid (Bactericera cockerelli; Hemiptera: Triozidae.
Full Text Available The potato psyllid, Bactericera cockerelli (Šulc (Hemiptera: Triozidae, is a vector of the phloem-limited bacterium 'Candidatus Liberibacter solanacearum' (Lso, the putative causal agent of zebra chip disease of potato. Little is known about how potato psyllid transmits Lso to potato. We used electrical penetration graph (EPG technology to compare stylet probing behaviors and efficiency of Lso transmission of three haplotypes of potato psyllid (Central, Western, Northwestern. All haplotypes exhibited the full suite of stylet behaviors identified in previous studies with this psyllid, including intercellular penetration and secretion of the stylet pathway, xylem ingestion, and phloem activities, the latter comprising salivation and ingestion. The three haplotypes exhibited similar frequency and duration of probing behaviors, with the exception of salivation into phloem, which was of higher duration by psyllids of the Western haplotype. We manipulated how long psyllids were allowed access to potato ("inoculation access period", or IAP to examine the relationship between phloem activities and Lso transmission. Between 25 and 30% of psyllids reached and salivated into phloem at an IAP of 1 hr, increasing to almost 80% of psyllids as IAP was increased to 24 h. Probability of Lso-transmission was lower across all IAP levels than probability of phloem salivation, indicating that a percentage of infected psyllids which salivated into the phloem failed to transmit Lso. Logistic regression showed that probability of transmission increased as a function of time spent salivating into the phloem; transmission occurred as quickly as 5 min following onset of salivation. A small percentage of infected psyllids showed extremely long salivation events but nonetheless failed to transmit Lso, for unknown reasons. Information from these studies increases our understanding of Lso transmission by potato psyllid, and demonstrates the value of EPG technology in
Psyllids (Hemiptera: Pyslloidea) harbor bacterial symbionts in specialized organs called bacteriomes. Bacteriomes may be subject to manipulation to control psyllid pests including Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) and Cacopsylla pyricola (Forster) (Hemiptera: Psyllidae) if the bi...
Long term, sustainable management of zebra chip disease of potato, caused by “Candidatus Liberibacter solanacearum” (Lso) and vectored by potato psyllids (Bactericera cockerelli Sulc), will require development of new cultivars resistant or tolerant to infection and/or capable of reducing spread. The...
Full Text Available Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae is reported on Brassica oleracea var. capitata (Brassicaceae in northwestern Iran. Tamarixia monesus (Walker (Hymenoptera: Chalcidoidea, Eulophidae was reared for the first time on B. tremblayi, and compared with Tamarixia tremblayi, another parasitoid of B. tremblayi. This is a new record of T. monesus from the Middle East.
Swisher, Kylie D; Munyaneza, Joseph E; Crosslin, James M
The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), is an economically important pest of potato (Solanum tuberosum L.) crops across the western and central United States, as it is known to cause psyllid yellows disease and to transmit the bacterium that causes zebra chip disease. Recent genotyping of B. cockerelli collected during the 2011 potato growing season identified three psyllid haplotypes within the western and central United States according to their geographical regions: northwestern, western, and central. To understand potato psyllid population dynamics before the year 2011, high resolution melting analysis of the B. cockerelli mitochondrial cytochrome oxidase I-like gene was used to identify the haplotypes of over 450 archived psyllids collected in the western and central United States between the years 1998 and 2010. Results show that the northwestern haplotype was present in Washington State as early as 1998 and has persisted in this region since that time. Likewise, psyllids of the western haplotype have also been present in Washington and Oregon before 2011.
Ebie, Jessica D.; Hölldobler, Bert; Liebig, Jürgen
Although workers in many ant species are capable of producing their own offspring, they generally rear the queen's offspring instead. There are various mechanisms that regulate worker reproduction including inhibitory effects of ant brood. Colonies of the ant Novomessor cockerelli are monogynous and polydomous resulting in a large portion of nest workers being physically isolated from the queen for extended periods of time. Some workers experimentally isolated from the queen in laboratory nests lay viable eggs, which develop into males. We investigate the mechanism that regulates worker fertility in subnests separated from the queen by giving queenless worker groups queen-produced larvae, queen-produced eggs, or no brood. Our findings show that larvae delay the time to worker egg-laying, but eggs have no effect. Larval inhibition is a likely mechanism that contributes to the regulation of worker reproduction in N. cockerellli because larvae are easily transported to subnests that do not contain a queen.
Smith, Adrian A.; Hölldobler, Bert; Liebig, Jürgen
In many social taxa, reproductively dominant individuals sometimes use aggression to secure and maintain reproductive status. In the social insects, queen aggression towards subordinate individuals or workers has been documented and is predicted to occur only in species with a small colony size and a low level of queen-worker dimorphism. We report queen aggression towards reproductive workers in the ant species Aphaenogaster cockerelli, a species with a relatively large colony size and a high level of reproductive dimorphism. Through analysis of cuticular hydrocarbon profiles, we show that queens are aggressive only to reproductively active workers. Non-reproductive workers treated with a hydrocarbon typical for reproductives are attacked by workers but not by queens, which suggests different ways of recognition. We provide possible explanations of why queen aggression is observed in this species.
Full Text Available The potato/tomato psyllid, Bactericerca cockerelli (B. cockerelli, and the Asian citrus psyllid, Diaphorina citri (D. citri, are very important plant pests, but they are also vectors of phloem-limited bacteria that are associated with two devastating plant diseases. B. cockerelli is the vector of Candidatus Liberibacter psyllaurous (solanacearum, which is associated with zebra chip disease of potatoes, and D. citri is the vector of Ca. Liberibacter asiaticus, which is associated with the Huanglongbing (citrus greening disease that currently threatens the entire Florida citrus industry. Here we used EST sequence information from D. citri to identify potential targets for RNA interference in B. cockerelli. We targeted ubiquitously expressed and gut-abundant mRNAs via injection and oral acquisition of double-stranded RNAs and siRNAs and were able to induce mortality in recipient psyllids. We also showed knockdown of target mRNAs, and that oral acquisition resulted primarily in mRNA knockdown in the psyllid gut. Concurrent with gene knockdown was the accumulation of target specific ∼ 21 nucleotide siRNAs for an abundant mRNA for BC-Actin. These results showed that RNAi can be a powerful tool for gene function studies in psyllids, and give support for continued efforts for investigating RNAi approaches as possible tools for psyllid and plant disease control.
We examined the effects of photoperiod on reproductive diapause of three haplotypes of potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae), collected from three geographic locations: south Texas (Central haplotype), California (Western haplotype), and Washington State (Northwestern haploty...
Tobacco plants with symptoms resembling those associated with the psyllid Bactericera cockerelli and the bacterium “Candidatus Liberibacter solanacearum” (Lso) were observed in April of 2012 in heavily B. cockerelli-infested commercial fields in the Department of El-Paraíso, Honduras; all cultivars ...
Goolsby, J A; Adamczyk, J J; Crosslin, J M; Troxclair, N N; Anciso, J R; Bester, G G; Bradshaw, J D; Bynum, E D; Carpio, L A; Henne, D C; Joshi, A; Munyaneza, J E; Porter, P; Sloderbeck, P E; Supak, J R; Rush, C M; Willett, F J; Zechmann, B J; Zens, B A
The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), and its associated pathogen "Candidatus Liberibacter solanacearum" (Ca. L. solanacearum), the putative causal agent of zebra chip (ZC) disease in potatoes (Solanum tuberosum L.), were sampled in commercial potato fields and untreated control plots for 3 yr in multiple locations in Texas, Kansas, Nebraska, and Colorado. Populations of the potato psyllid varied across years and across potato growing regions. However, the percentage of potato psyllids infected with Ca. L. solanacearum although variable across years, was consistently highest in the Lower Rio Grande Valley of Texas (LRGV), the reported overwintering location for this pest. The numbers of Ca. L. solanacearum-infected psyllids collected on field traps and large nymphs counted on leaf samples were both positively correlated with the final percentage of ZC in tubers. In the LRGV, where vector and disease pressure is the highest, population levels of immature life stages of the psyllid and percentage of ZC differed greatly between commercial and untreated fields. These results show that the pest management program that was used can be effective at controlling development of the psyllid and ultimately reducing the incidence of ZC.
María Berenice González Maldonado
Full Text Available In Sinaloa the vegetable and cucurbits production are important agricultural activities, so each year a high volume of chemicalinsecticides are applied to pest control that attack these crops. This paper present the main pests insects in the region, as wellas an analysis about effects of biorational insecticides on these pests. Was found that for control of Bemisia argentifolii Bellows & Perring (Hemiptera: Aleyrodidae is used Neem oil 0.2%., for kill nymphs of Bactericera cockerelli Sulc. (Homoptera: Psyllidae soursop Annona muricata L. (Annonales: Annonaceae at doses of 2500-5000 mg/L., for Liriomyza trifolii Burgess (Diptera: Agromyzidae neem seeds 2%., to Myzus persicae Sulzer (Hemiptera: Aphididae rapeseed oil at doses 920 g/L (2% v/v., to Frankliniella occidentalis Pergande (Thysanoptera: Thripidae spinosad (Conserve® 48-60 mg/L., and for Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae granular viruses (105 OBs/mL combined with neem (DalNeem TM emulsifiable oil and NeemAzal TM -T/S at doses of 8 mg/L, everyone. The use of these products and the dose depends on the type of pest and crop. In general these products cause insect mortality greater than 95%, besides having low toxicity on natural enemies, so that these can be used individually or in combination in integrated pest control schemes against vegetable pests, and also for disease vectors insects in the northern of Sinaloa.
Tonja W. Fisher
Full Text Available The potato psyllid (PoP Bactericera cockerelli (Sulc and Asian citrus psyllid (ACP Diaphorina citri Kuwayama are the insect vectors of the fastidious plant pathogen, Candidatus Liberibacter solanacearum (CLso and Ca. L. asiaticus (CLas, respectively. CLso causes Zebra chip disease of potato and vein-greening in solanaceous species, whereas, CLas causes citrus greening disease. The reliance on insecticides for vector management to reduce pathogen transmission has increased interest in alternative approaches, including RNA interference to abate expression of genes essential for psyllid-mediated Ca. Liberibacter transmission. To identify genes with significantly altered expression at different life stages and conditions of CLso/CLas infection, cDNA libraries were constructed for CLso-infected and -uninfected PoP adults and nymphal instars. Illumina sequencing produced 199,081,451 reads that were assembled into 82,224 unique transcripts. PoP and the analogous transcripts from ACP adult and nymphs reported elsewhere were annotated, organized into functional gene groups using the Gene Ontology classification system, and analyzed for differential in silico expression. Expression profiles revealed vector life stage differences and differential gene expression associated with Liberibacter infection of the psyllid host, including invasion, immune system modulation, nutrition, and development.
Full Text Available Plants produce specific volatile organic compound (VOC blends in response to herbivory. Herbivore-induced blends may prime the plant for future attack or attract carnivorous insects; these responses have been considered adaptive for plants. If herbivores differentially modify the VOC emission among individuals within a group of plants they feed upon, then plant responses to herbivores will not only produce specific blends but also variation in odor among individuals, i.e. individuals smell the same, then having a uniform odor. We investigated the VOC emission variation or uniformity among tomato individuals (Solanum lycopersicum L. cv. Castlemart in response to moderate wounding by (1 nymphs of the psyllid Bactericera cockerelli (Sulc. (TP; (2 Lepidoptera chewing-feeding larvae of Fall Armyworm (Spodoptera frugiperda Smith (FAW and (3 of Cabbage Looper (Trichoplusia ni Hübner (CL, and (4 mechanical damage (MD. We used a ratio-based analysis to compare the fold-change in concentration from constitutive to induced VOC emission. We also used size and shape analysis to compare the emission of damaged and non-damaged individuals. Aside of finding herbivore-specific blends in line with other studies, we found patterns not described previously. We detected constitutive and induced odor variation among individuals attacked by the same herbivore, with the induced odor uniformity depending on the herbivore identity. We also showed that the fold-change of VOCs from constitutive to induced state differed among individuals independently of the uniformity of the blends before herbivore attack. We discuss our findings in the context of the ecological roles of VOCs in plant-plant and plant-carnivore insects' interactions.
Zebra chip disease is associated with infections by ‘Candidatus Liberibacter solanacearum’ (Lso), a bacterium spread by the potato psyllid Bactericera cockerelli. A major concern of the potato industry is the likelihood that Lso could cause asymptomatic infections prior to placement of tubers in col...
The potato psyllid, Bactericera cockerelli, is as an economically important insect pest of potatoes in the western U.S., Mexico, Central America and New Zealand. This insect has historically been linked to psyllid yellows disease, but more recently has been shown to be the vector of a bacterium that...
Zeilinger, Adam R; Rapacciuolo, Giovanni; Turek, Daniel; Oboyski, Peter T; Almeida, Rodrigo P P; Roderick, George K
The emergence rate of new plant diseases is increasing due to novel introductions, climate change, and changes in vector populations, posing risks to agricultural sustainability. Assessing and managing future disease risks depends on understanding the causes of contemporary and historical emergence events. Since the mid-1990s, potato growers in the western United States, Mexico, and Central America have experienced severe yield loss from Zebra Chip disease and have responded by increasing insecticide use to suppress populations of the insect vector, the potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae). Despite the severe nature of Zebra Chip outbreaks, the causes of emergence remain unknown. We tested the hypotheses that (1) B. cockerelli occupancy has increased over the last century in California and (2) such increases are related to climate change, specifically warmer winters. We compiled a data set of 87,000 museum specimen occurrence records across the order Hemiptera collected between 1900 and 2014. We then analyzed changes in B. cockerelli distribution using a hierarchical occupancy model using changes in background species lists to correct for collecting effort. We found evidence that B. cockerelli occupancy has increased over the last century. However, these changes appear to be unrelated to climate changes, at least at the scale of our analysis. To the extent that species occupancy is related to abundance, our analysis provides the first quantitative support for the hypothesis that B. cockerelli population abundance has increased, but further work is needed to link B. cockerelli population dynamics to Zebra Chip epidemics. Finally, we demonstrate how this historical macro-ecological approach provides a general framework for comparative risk assessment of future pest and insect vector outbreaks. © 2017 by the Ecological Society of America.
Cerón González, Claudia
Tamarixia triozae es un ectoparasitoide con alto potencial para su uso en programas de manejo integrado del psílido de la papa, Bactericera cockerelli. Aunque ya se produce comercialmente, no existe información de su almacenaje a bajas temperaturas, esta información puede tener importancia para optimizar la conservación de estos organismos. En el presente trabajo se evaluó la respuesta de pupas y adultos de T. triozae después de almacenarlos a 5, 8 y 10°C por 7, 14 y 21 días. Los resultados s...
Ravindran, Aravind; Lévy, Julien; Pierson, Elizabeth; Gross, Dennis C
An efficient loop-mediated isothermal amplification procedure (LAMP) for the detection of "Candidatus Liberibacter solanacearum" (Lso), the bacterial causal agent of potato zebra chip (ZC) disease, is described in this chapter. Similar to the polymerase chain reaction (PCR), the LAMP employs a bacterial polymerase to amplify specific DNA sequences. However, the method differs from conventional PCR in that it uses six primers specific to the target region to generate a loop structure and autocycling strand displacement rather than thermocycling for sequence amplification. Moreover, unlike PCR that requires agarose gel electrophoresis for resolution, the positive LAMP results can be visualized directly as a precipitate within the reaction tubes. The 16S rDNA gene of "Ca. Liberibacter solanacearum" was used as the target for the design of the six LAMP primers. The LAMP technique is a reliable, rapid, and cost-effective method of detecting the "Ca. Liberibacter solanacearum" pathogen in the potato/tomato psyllid, Bactericera cockerelli, and in field-grown potato plants and tubers.
Alvarado, Veria Y; Odokonyero, Denis; Duncan, Olivia; Mirkov, T Erik; Scholthof, Herman B
Zebra complex (ZC) disease on potatoes is associated with Candidatus Liberibacter solanacearum (CLs), an α-proteobacterium that resides in the plant phloem and is transmitted by the potato psyllid Bactericera cockerelli (Šulc). The name ZC originates from the brown striping in fried chips of infected tubers, but the whole plants also exhibit a variety of morphological features and symptoms for which the physiological or molecular basis are not understood. We determined that compared to healthy plants, stems of ZC-plants accumulate starch and more than three-fold total protein, including gene expression regulatory factors (e.g. cyclophilin) and tuber storage proteins (e.g., patatins), indicating that ZC-affected stems are reprogrammed to exhibit tuber-like physiological properties. Furthermore, the total phenolic content in ZC potato stems was elevated two-fold, and amounts of polyphenol oxidase enzyme were also high, both serving to explain the ZC-hallmark rapid brown discoloration of air-exposed damaged tissue. Newly developed quantitative and/or conventional PCR demonstrated that the percentage of psyllids in laboratory colonies containing detectable levels of CLs and its titer could fluctuate over time with effects on colony prolificacy, but presumed reproduction-associated primary endosymbiont levels remained stable. Potato plants exposed in the laboratory to psyllid populations with relatively low-CLs content survived while exposure of plants to high-CLs psyllids rapidly culminated in a lethal collapse. In conclusion, we identified plant physiological biomarkers associated with the presence of ZC and/or CLs in the vegetative potato plant tissue and determined that the titer of CLs in the psyllid population directly affects the rate of disease development in plants.
Fu, Zhen; Epstein, Brendan; Kelley, Joanna L; Zheng, Qi; Bergland, Alan O; Castillo Carrillo, Carmen I; Jensen, Andrew S; Dahan, Jennifer; Karasev, Alexander V; Snyder, William E
Herbivores often move among spatially interspersed host plants, tracking high-quality resources through space and time. This dispersal is of particular interest for vectors of plant pathogens. Existing molecular tools to track such movement have yielded important insights, but often provide insufficient genetic resolution to infer spread at finer spatiotemporal scales. Here, we explore the use of Nextera-tagmented reductively-amplified DNA (NextRAD) sequencing to infer movement of a highly-mobile winged insect, the potato psyllid (Bactericera cockerelli), among host plants. The psyllid vectors the pathogen that causes zebra chip disease in potato (Solanum tuberosum), but understanding and managing the spread of this pathogen is limited by uncertainty about the insect's host plant(s) outside of the growing season. We identified 1,978 polymorphic loci among psyllids separated spatiotemporally on potato or in patches of bittersweet nightshade (S. dulcumara), a weedy plant proposed to be the source of potato-colonizing psyllids. A subset of the psyllids on potato exhibited genetic similarity to insects on nightshade, consistent with regular movement between these two host plants. However, a second subset of potato-collected psyllids was genetically distinct from those collected on bittersweet nightshade; this suggests that a currently unrecognized source, i.e., other nightshade patches or a third host-plant species, could be contributing to psyllid populations in potato. Oftentimes, dispersal of vectors of pathogens must be tracked at a fine scale in order to understand, predict, and manage disease spread. We demonstrate that emerging sequencing technologies that detect genome-wide SNPs of a vector can be used to infer such localized movement.
Houwink, A.; Nijland, R.H.; Geurts, A.C.; Kwakkel, G.
Objective: To describe recovery of upper limb capacity after stroke during inpatient rehabilitation based on the Stroke Upper Limb Capacity Scale (SULCS). Design: Prospective observational study. Setting: Inpatient department of a rehabilitation center. Participants: Patients with stroke (N=299)
Houwink, A.; Nijland, R.H.; Geurts, A.C.H.; Kwakkel, G.
OBJECTIVE: To describe recovery of upper limb capacity after stroke during inpatient rehabilitation based on the Stroke Upper Limb Capacity Scale (SULCS). DESIGN: Prospective observational study. SETTING: Inpatient department of a rehabilitation center. PARTICIPANTS: Patients with stroke (N=299)
Tsai, Shu Fen; Lin, Chao Yuan
In 1976, "Slopeland Conservation and Utilization Act" was promulgated as well as the criteria for slopeland utilization limitation classification (SULC) i.e., average slope, effective soil depth, degree of soil erosion, and parent rock became standardized. Due to the development areas on slope land steadily increased and the extreme rainfall events occurred frequently, the areas affected by landslides also increased year by year. According to the act, the land which damaged by disaster must be categorized to the conservation land and required rehabilitation. Nevertheless, the large-scale disaster on slope land and the limitation of SWCB officers are the constraint of field investigation. Therefore, how to establish the ongoing inspective procedure of post-disaster SULC using remote sensing was essential. A-Li-Shan, Ai-Liao, and Tai-Ma-Li Watershed were selected to be case studies in this project. The spatial data from big data i.e., Digital Elevation Model (DEM), soil map, and satellite images integrated with Geographic Information Systems (GIS) were applied to post-disaster SULC. The collapse and deposition area which delineated by vegetation recovery rate was established landslide inventory of cadastral unit combined with watershed unit. The results were verified with field survey and the accuracy was 97%. The landslide inventory could be an effective reference for sediment disaster investigation and a practical evidence for judgement to expropriation. Finally, the results showed that the ongoing inspective procedure of post-disaster SULC was practicable. From the four criteria, the average slope was the major factor. It was found that the non-uniform slopes, especially derived from cadastral units, often produce significant slope difference and lead to errors of average slope evaluation. Therefore, the Grid-based DEM slope derivation has been recommended as the standard method to calculate the average slope. Others criteria were previously required to classify
Prange, Gerdienke B; Kottink, Anke I R; Buurke, Jaap H; Eckhardt, Martine M E M; van Keulen-Rouweler, Bianca J; Ribbers, Gerard M; Rietman, Johan S
Use of rehabilitation technology, such as (electro)mechanical devices or robotics, could partly relieve the increasing strain on stroke rehabilitation caused by an increasing prevalence of stroke. Arm support (AS) training showed improvement of unsupported arm function in chronic stroke. To examine the effect of weight-supported arm training combined with computerized exercises on arm function and capacity, compared with dose-matched conventional reach training in subacute stroke patients. In a single-blind, multicenter, randomized controlled trial, 70 subacute stroke patients received 6 weeks of training with either an AS device combined with computerized exercises or dose-matched conventional training (CON). Arm function was evaluated pretraining and posttraining by Fugl-Meyer assessment (FM), maximal reach distance, Stroke Upper Limb Capacity Scale (SULCS), and arm pain via Visual Analogue Scale, in addition to perceived motivation by Intrinsic Motivation Inventory posttraining. FM and SULCS scores and reach distance improved significantly within both groups. These improvements and experienced pain did not differ between groups. The AS group reported higher interest/enjoyment during training than the CON group. AS training with computerized exercises is as effective as conventional therapy dedicated to the arm to improve arm function and activity in subacute stroke rehabilitation, when applied at the same dose. © The Author(s) 2014.
Teresani, G.; Hernández, E.; Bertolini, E.; Siverio, F.; Marroquín, C.; Molina, J.; Hermoso de Mendoza, A.; Cambra, M.
‘Candidatus Liberibacter solanacearum’ has recently been reported to be associated with vegetative disorders and economic losses in carrot and celery crops in Spain. The bacterium is a carrot seedborne pathogen and it is transmitted by psyllid vector species. From 2011 to 2014 seasonal and occasional surveys in carrot, celery and potato plots were performed. The sticky plant method was used to monitor the arthropods that visited the plants. The collected arthropods were classified into Aphididae and Cicadellidae, and the superfamily Psylloidea was identified to the species level. The superfamily Psylloidea represented 35.45% of the total arthropods captured on celery in Villena and 99.1% on carrot in Tenerife (Canary Islands). The maximum flight of psyllid species was in summer, both in mainland Spain and the Canary Islands, reaching a peak of 570 specimens in August in Villena and 6,063 in July in Tenerife. The main identified psyllid species were as follows: Bactericera trigonica Hodkinson, B. tremblayi Wagner and B. nigricornis Förster. B. trigonica represented more than 99% of the psyllids captured in the Canary Islands and 75% and 38% in 2011 and 2012 in Villena, respectively. In addition, Trioza urticae Linnaeus, Bactericera sp., Ctenarytaina sp., Cacopsylla sp., Trioza sp. and Psylla sp. were captured. ‘Ca. L. solanacearum’ targets were detected by squash real-time PCR in 19.5% of the psyllids belonging to the different Bactericera species. This paper reports at least three new psyllid species that carry the bacterium and can be considered as potential vectors. (Author)
Full Text Available Candidatus Liberibacter solanacearum’ has recently been reported to be associated with vegetative disorders and economic losses in carrot and celery crops in Spain. The bacterium is a carrot seedborne pathogen and it is transmitted by psyllid vector species. From 2011 to 2014 seasonal and occasional surveys in carrot, celery and potato plots were performed. The sticky plant method was used to monitor the arthropods that visited the plants. The collected arthropods were classified into Aphididae and Cicadellidae, and the superfamily Psylloidea was identified to the species level. The superfamily Psylloidea represented 35.45% of the total arthropods captured on celery in Villena and 99.1% on carrot in Tenerife (Canary Islands. The maximum flight of psyllid species was in summer, both in mainland Spain and the Canary Islands, reaching a peak of 570 specimens in August in Villena and 6,063 in July in Tenerife. The main identified psyllid species were as follows: Bactericera trigonica Hodkinson, B. tremblayi Wagnerand B. nigricornis Förster. B. trigonica represented more than 99% of the psyllids captured in the Canary Islands and 75% and 38% in 2011 and 2012 in Villena, respectively. In addition, Trioza urticae Linnaeus, Bactericera sp.,Ctenarytaina sp., Cacopsylla sp., Trioza sp. and Psylla sp. were captured. ‘Ca. L. solanacearum’ targets were detected by squash real-time PCR in 19.5% of the psyllids belonging to the different Bactericera species. This paper reports at least three new psyllid species that carry the bacterium and can be considered as potential vectors.
Full Text Available 000227 |pid:none) Bacillus cereus Q1, complete ge... 114 3e-23 B83991( B83991 ) glycolate oxidase subunit BH2730 [imported...ana interm... 56 2e-15 5 ( AF211126 ) Carsonella ruddii natural-host Bactericera cocker....psnkfvpqrlfqq*fvf tiqrkln*vllgnqvkvl*vnsqvqwlksifitfvplisrmfvslslvskvqrrl*isie lqfsissprmlplv*vlllvklgpkkdmi... la... 1074 0.0 1 ( AB000109 ) Dictyostelium discoideum mitochondrial DNA, compl... 1074 0.0 1 ( BJ412759 ) Dictyosteli...7, 3' ... 731 0.0 1 ( DQ336395 ) Dictyostelium citrinum mitochondrion, complete ge... 456 0.0 3 ( BJ387435 ) Dictyosteli
Dollin, Anne E; Dollin, Leslie J; Rasmussen, Claus
The stingless bee genus Austroplebeia Moure occurring in Australia and New Guinea is revised, based on a morphological analysis of samples from 177 colonies. Five species are recognised: A. cincta (Mocsáry), A. essingtoni (Cockerell), A. australis (Friese), A. cassiae (Cockerell) and A. magna, sp. nov. Three different colour morphs of A. australis are described. Five new synonymies are proposed: A. cockerelli (Rayment), A. ornata (Rayment), A. percincta (Cockerell) and A. websteri (Rayment) = A. australis; A. symei (Rayment) = A. cassiae. Workers, males and queens are described for all species. Populations of A. cincta, recently found in Queensland, Australia, are compared with A. cincta from the type locality and other areas in New Guinea. A lectotype is designated for A. percincta (Cockerell). Provenance of type material is discussed. A key to the species, distributions and nest descriptions are provided.
Bustamante, Abel A; Maddison, Wayne P; Ruiz, Gustavo R S
In this paper we call attention to the identity of the type species of Thiodina Simon, 1900, T. nicoleti Roewer, 1951. When Simon proposed the genus, he characterized it based on morphological features found in species he described, but not found in the type species he designated, and whose type specimens, apparently, he had not examined. Nicolet's original description makes it clear that the type species is not closely related to the more familiar species placed in the genus. This misinterpretation was followed by contemporary researchers and survives until today. Here we designate and describe a neotype for T. nicoleti. We revalidate Colonus F.O.P.-Cambridge, 1901 and Nilakantha Peckham & Peckham, 1901 to transfer most species formerly placed in Thiodina. The combinations Colonus puerperus (Hentz, 1846), Nilakantha cockerelli Peckham & Peckham, 1901 and N. peckhami Bryant, 1940 are restored. The following new combinations are established: Colonus branicki (Taczanowski, 1871) new comb., C. candidus (Mello-Leitão, 1922) new comb., C. germaini (Simon, 1900) new comb., C. hesperus (Richman & Vetter, 2004) new comb., C. melanogaster (Mello-Leitão, 1917) new comb., C. pallidus (C.L. Koch, 1846) new comb., C. pseustes (Chamberlin & Ivie, 1936) new comb., C. punctulatus (Mello-Leitão, 1917) new comb., C. rishwani (Makhan, 2006) new comb., C. robustus (Mello-Leitão, 1945) new comb., C. sylvanus (Hentz, 1846) new comb., C. vaccula (Simon, 1900) new comb., C. vellardi (Soares & Camargo, 1948) new comb., Nilakantha beugelorum (Wolff, 1990) new comb., N. crucifera (F.O.P.-Cambridge, 1901) new comb., and N. inerma (Bryant, 1940) new comb. Thiodina setosa Mello-Leitão, 1947 is tentatively transferred to Cotinusa Simon, 1900.
Phenacoccinae de Centro y Sudamérica (Hemiptera: Coccoidea: Pseudococcidae: Sistemática y Filogenia Central and South American Phenacoccinae (Hemiptera: Coccoidea: Pseudococcidae: Systematics and Phylogeny
María Cristina Granara De Willink
Full Text Available Se presenta un estudio sistemático y cladístico de las especies de Phenacoccus Cockerell neotropicales. Se describen e ilustran 18 especies nuevas: Phenacoccus argentinus Granara de Willink, Ph. berberis Granara de Willink, Ph. chubutensis Granara de Willink, Ph. ornatus Granara de Willink, Ph. persimilis Granara de Willink (Argentina; Ph. erythrinus Granara de Willink (Brasil y Argentina; Ph. peruvianus Granara de Willink (Argentina y Perú; Ph. sisymbriifolium Granara de Willink (Argentina y Uruguay; Ph. chilindrinae Granara de Willink, Ph. cornicirculus Granara de Willink, Ph. ruellia Granara de Willink, Ph. setosus Granara de Willink, Ph. sonoraensis Granara de Willink (México; Ph. hirsutus Granara de Willink (Puerto Rico; Ph. multicerarii Granara de Willink (Venezuela; Ph. sisalanus Granara de Willink (Haití y República Dominicana; Ph. toconaoensis Granara de Willink (Chile, y Ph. uruguayensis Granara de Willink (Uruguay. Todas las especies de Phenacoccus conocidas anteriormente para la región (24 en total son diagnosticadas. También se citan, ilustran y describen Phenacoccus artemisiae Ehrhorn y Ph. graminicola Leonardi, encontradas por primera vez en la Argentina. Se incluyen claves de géneros de Phenacoccinae neotropicales y de las especies de Phenacoccus neotropicales y también una lista de plantas hospederas de los Phenacoccus, que contiene 48 Familias Botánicas y 124 especies. Finalmente se realizó un análisis cladístico de los Phenacoccinae neotropicales, que incluye además de Phenacoccus los siguientes géneros: Brasiliputo Williams & Granara de Willink, Brevennia Goux, Chileputo Williams & Granara de Willink, Heliococcus Sulc, Heterococcus Ferris, Mammicoccus Balachowsky, Peliococcus Borchsenius, Pellizzaricoccus Kozár. Una matriz de 60 taxones (que incluye 10 géneros y 111 caracteres morfológicos, fue analizada mediante el criterio de parsimonia con el género Puto Signoret como taxón raíz. Los resultados